記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Ventricular tachycardia originating from the left ventricular summit region, the most superior region of the left ventricle surrounded by the major coronary arteries and veins, is frequently refractory to pharmacological therapies and endocardial and epicardial catheter ablation. METHODS: Eleven patients with an age from 31 to 79 (median 56) years old, underwent map-guided surgery for left ventricular summit ventricular tachycardia. All patients had undergone one to 5 unsuccessful sessions of catheter ablation for incessant ventricular tachycardia, preoperatively. Five patients had suffered ventricular tachycardia storm and 1 had a history of cardiopulmonary resuscitation. Four patients had implanted with a defibrillator. Epicardium to endocardium transmural cryothermia was applied at the ventricular tachycardia origin determined by intraoperative epicardial mapping with electro-anatomical mapping system. Harmonic scalpel was used to remove the epicardial fat and cryothermia was applied directly to the myocardium, avoiding thermal or mechanical injuries to the coronary vessels. Additional endocardial cryothermia at the ventricular tachycardia origin was performed by a cryoprobe introduced into the left ventricular cavity through an aortotomy. RESULTS: There was no surgical mortality or long-term mortality related to ventricular tachycardia during a median follow-up period of 60 months (IQR: 34-82). Five-year freedom from preoperatively documented left ventricular summit ventricular tachycardia and non-documented ventricular tachycardia was 91% and 73%, respectively. All the patients with postoperative ventricular tachycardia underwent successful catheter ablation. Other patients were free from ventricular tachycardia during the follow-up period. CONCLUSIONS: Epicardial to endocardial transmural cryothermia at the ventricular tachycardia origin guided by intraoperative electro-anatomical mapping with a close collaboration with electrophysiologists was crucial in successful surgery for left ventricular summit ventricular tachycardia.

DOI： 10.1093/ejcts/ezad323

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/S0140-6736(23)01675-6

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

INTRODUCTION: Cardiac resynchronization therapy (CRT) is well-established for treating symptomatic heart failure with electrical dyssynchrony. The left ventricular (LV) lead position is recommended at LV posterolateral to lateral sites in patients with left bundle branch block; however, its preferred region remains unclear in patients being upgraded from right ventricular (RV) apical pacing to CRT. This study aimed to identify the preferred LV lead position for upgrading conventional RV apical pacing to CRT. METHODS: We used electrode catheters positioned at the RV apex and LV anterolateral and posterolateral sites via the coronary sinus (CS) branches to measure the ratio of activation time to QRS duration from the RV apex to the LV anterolateral and posterolateral sites during RV apical pacing. Simultaneous biventricular pacing was performed at the RV apex and each LV site, and the differences in QRS duration and LV dP/dtmax from those of RV apical pacing were measured. RESULTS: Thirty-seven patients with anterolateral and posterolateral LV CS branches were included. During RV apical pacing, the average ratio of activation time to QRS duration was higher at the LV anterolateral site than at the LV posterolateral site (0.90 ± 0.06 vs. 0.71 ± 0.11, p < .001). The decreasing ratio of QRS duration and the increasing ratio of LV dP/dtmax were higher at the LV anterolateral site than at the posterolateral site (45.7 ± 18.0% vs. 32.0 ± 17.6%, p < .001; 12.7 ± 2.9% vs. 3.7 ± 8.2%, p < .001, respectively) during biventricular pacing compared with RV apical pacing. CONCLUSION: The LV anterolateral site is the preferred LV lead position in patients being upgraded from conventional RV apical pacing to CRT.

DOI： 10.1111/jce.16005

PubMed

researchmap

記述言語：日本語   出版者・発行元：(一社)日本病院総合診療医学会  

researchmap

記述言語：日本語   出版者・発行元：臨床心臓電気生理研究会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

AIMS: Maintenance of euvolaemia with diuretics is critical in heart failure (HF) patients with chronic kidney disease (CKD); however, it is challenging because no reliable marker of volume status exists. Fractional excretion of urea nitrogen (FEUN) is a useful index of volume status in patients with renal failure. We aimed to examine whether FEUN is a surrogate marker of volume status for risk stratification in HF patients with CKD. METHODS AND RESULTS: We examined 516 HF patients with CKD (defined as discharge estimated glomerular filtration rate < 60 mL/min/1.73 m2 ) whose FEUN was measured at discharge (median age, 80 years; 58% male). The patients were divided into four groups according to quartile FEUN value at discharge: low-FEUN, FEUN ≤ 32.1; medium-FEUN, 32.1 < FEUN ≤ 38.0; high-FEUN, 38.0 < FEUN ≤ 43.7; and extremely-high-FEUN, FEUN > 43.7. FEUN was calculated by the following formula: (urinary urea × serum creatinine) × 100/(serum urea × urinary creatinine). During the 3 year follow-up, 131 HF readmissions occurred. Kaplan-Meier analysis showed that the HF readmission rate was significantly lower in the medium-FEUN group than in the other three groups (log-rank test, P = 0.029). Multivariate Cox regression analysis identified the low-FEUN, high-FEUN, and extremely-high-FEUN values as independent factors associated with post-discharge HF readmission. In the analysis of 130 patients who underwent right heart catheterization during hospitalization, a significant correlation between FEUN value and right atrial pressure was observed (R = 0.243, P = 0.005). Multivariate linear regression analysis revealed that FEUN value at discharge decreased in a dose-dependent manner with loop diuretics. CONCLUSIONS: In HF patients with CKD, FEUN is a potential marker of volume status for risk stratification of post-discharge HF readmission. Low FEUN value (FEUN ≤ 32.1) may represent intravascular dehydration, whereas high FEUN value (FEUN > 38.0) may represent residual congestion; both of them were independent risk factors for HF readmission. FEUN may be useful to determine euvolaemia and guide fluid management in HF patients with CKD.

DOI： 10.1002/ehf2.14327

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

INTRODUCTION: Data are lacking on the extent to which patients with non-valvular atrial fibrillation (AF) who are aged ≥80 years benefit from ablation treatment. The question pertains especially to patients' postablation quality of life (QoL) and long-term clinical outcomes. METHODS AND ANALYSIS: We are initiating a prospective, registry-based, multicentre observational study that will include patients aged ≥80 years with non-valvular AF who choose to undergo treatment by catheter ablation and, for comparison, such patients who do not choose to undergo ablation (either according to their physician's advice or their own preference). Study subjects are to be enrolled from 52 participant hospitals and three clinics located throughout Japan from 1 June 2022 to 31 December 2023, and each will be followed up for 1 year. The planned sample size is 660, comprising 220 ablation group patients and 440 non-ablation group patients. The primary endpoint will be the composite incidence of stroke/transient ischaemic attack (TIA) or systemic embolism (SE), another cardiovascular event, major bleeding and/or death from any cause. Other clinical events such as postablation AF recurrence, a fall or bone fracture will be recorded. We will collect standard clinical background information plus each patient's Clinical Frailty Scale score, AF-related symptoms, QoL (Five-Level Version of EQ-5D) scores, Mini-Mental State Examination (optional) score and laboratory test results, including measures of nutritional status, on entry into the study and 1 year later, and serial changes in symptoms and QoL will also be secondary endpoints. Propensity score matching will be performed to account for covariates that could affect study results. ETHICS AND DISSEMINATION: The study conforms to the Declaration of Helsinki and the Ethical Guidelines for Clinical Studies issued by the Ministry of Health, Labour and Welfare, Japan. Results of the study will be published in one or more peer-reviewed journals. TRIAL REGISTRATION NUMBER: UMIN000047023.

DOI： 10.1136/bmjopen-2022-068894

PubMed

researchmap

出版者・発行元：株式会社 医学書院  

DOI： 10.11477/mf.1438200657

CiNii Research

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The Kumamoto criteria have been proposed as a non-invasive screen for transthyretin amyloid cardiomyopathy. This study assessed the validity of the Kumamoto criteria externally. Methods and Results: The study included 138 patients (median age 73 years; 65% male) who underwent 99 mTc-pyrophosphate (PYP) scintigraphy. Patients were divided into 4 groups according to total scores on the Kumamoto criteria (i.e., 0-3) for the following 3 factors: high-sensitivity cardiac troponin T ≥0.0308 ng/mL, wide (≥120 ms) QRS, and left ventricular posterior wall thickness ≥13.6 mm. The diagnostic performance and positive predictive value (PPV) of the Kumamoto criteria for positive 99 mTc-PYP scintigraphy were validated. Eighteen (13%) patients were positive on 99 mTc-PYP scintigraphy. The Kumamoto criteria had a favorable diagnostic performance (area under the curve 0.808). The PPV for groups with scores of 0, 1, 2, and 3 was 0% (n=0/42), 11% (n=6/57), 21% (n=7/33), and 83% (n=5/6), respectively, which is lower, particularly for those with a score of 2, than in the original Kumamoto cohort. However, the PPV increased after combining the Kumamoto criteria with a history of orthopedic diseases (spinal canal stenosis and/or carpal tunnel syndrome). Conclusions: This study suggests that the Kumamoto criteria have a favorable diagnostic performance; however, the PPV may decrease depending on the study population. Combining the Kumamoto criteria with the presence of orthopedic disease may improve the PPV.

DOI： 10.1253/circrep.CR-22-0110

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: A recent randomized trial demonstrated that catheter ablation for atrial fibrillation (AF) in patients with heart failure with reduced ejection fraction (EF) is associated with a reduction in death or heart failure. However, the effect of catheter ablation for AF in patients with heart failure with mid-range or preserved EF is unclear.Methods and Results: We screened 899 AF patients (72.4% male, mean age 68.4 years) with heart failure and left ventricular EF ≥40% from 2 Japanese multicenter AF registries: the Atrial Fibrillation registry to Follow the long-teRm Outcomes and use of aNTIcoagulants aftER Ablation (AF Frontier Ablation Registry) as the ablation group (525 patients who underwent ablation) and the Hokuriku-Plus AF Registry as the medical therapy group (374 patients who did not undergo ablation). Propensity score matching was performed in these 2 registries to yield 106 matched patient pairs. The primary endpoint was a composite of cardiovascular death and hospitalization for heart failure. At 24.6 months, the ablation group had a significantly lower incidence of the primary endpoint (hazard ratio 0.32; 95% confidence interval 0.13-0.70; P=0.004) than the medical therapy group. CONCLUSIONS: Compared with medical therapy, catheter ablation for AF in patients with heart failure and mid-range or preserved EF was associated with a significantly lower incidence of cardiovascular death or hospitalization for heart failure.

DOI： 10.1253/circj.CJ-22-0461

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Obstructive sleep apnea (OSA) is a highly prevalent disorder in patients with atrial fibrillation (AF). Although there has been an increase in the incidence of AF due to the aging population, it has been reported that OSA is still underdiagnosed because many patients remain asymptomatic or unaware of the symptoms associated with OSA, such as daytime sleepiness. Untreated OSA reduces the effectiveness of AF treatment, regardless of pharmacological or non-pharmacological modes of therapy, such as catheter ablation. Experimental and clinical studies have shown that OSA pathophysiology is multifactorial, comprising of hypoxemia, hypercapnia, autonomic dysfunction, negative intrathoracic pressure changes, and arousals of OSA, and lead to AF. Both the acute and long-term effects of obstructive apnea episodes are involved in the development of an arrhythmogenic substrate of AF. Undiagnosed OSA causes underutilized opportunities for more effective AF management. Therefore, it is important to screen for OSA in all patients being considered for rhythm control therapy. However, regardless of the growing evidence of the negative prognostic impact of OSA, there is a lack of awareness regarding this connection not only among patients but also among cardiologists and arrhythmia specialists. There is a barrier to performing a systemic screening for OSA in clinical practice. Therefore, it is important to establish a comprehensive OSA care team for the efficient diagnosis and treatment of OSA. This review provides the current understanding of OSA and its relationship to AF and the importance of the diagnosis and management of OSA in AF.

DOI： 10.1002/joa3.12784

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/joa3.12714

PubMed

researchmap

記述言語：日本語   出版者・発行元：医学図書出版(株)  

researchmap

記述言語：日本語   出版者・発行元：(公財)日本心臓財団  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The Japanese Catheter Ablation (J-AB) registry, started in August 2017, is a voluntary, nationwide, multicenter, prospective, observational registry, performed by the Japanese Heart Rhythm Society (JHRS) in collaboration with the National Cerebral and Cardiovascular Center using a Research Electronic Data Capture system. The purpose of this registry is to collect the details of target arrhythmias, the ablation procedures, including the type of target arrhythmias, outcomes, and acute complications in real-world settings. During the year 2020, we have collected a total of 84 591 procedures (mean age of 65.8 years and 66.6% male) from 466 participant hospitals. Detailed data were shown in Figures and Tables.

DOI： 10.1002/joa3.12772

PubMed

researchmap

記述言語：日本語   出版者・発行元：日本臨床生理学会  

researchmap

記述言語：日本語   出版者・発行元：日本サルコイドーシス  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Atrial fibrillation (AF) is the most common arrhythmia in patients undergoing hemodialysis (HD); AF lowers quality of life (QoL) and increases the risk of dialysis-related complications. The present study aimed to evaluate the effectiveness of AF ablation on the QoL in patients undergoing HD. Methods: Nineteen patients undergoing HD (14 men, age 68 ± 8 years; 15 with paroxysmal AF) who underwent catheter ablation (CA) of AF were enrolled in the study. The Kidney Disease Quality of Life Short Form (KDQOL-SF) was assessed to evaluate the QoL of the HD patients at baseline and 6 months after the ablation. Ablation outcomes and procedural complications were evaluated and compared to those of 1053 consecutive non-HD patients who underwent AF ablation. Results: The KDQOL-SF of the HD patients 6 months after the ablation showed an improvement in physical functioning (54 ± 23 to 68 ± 28, P < 0.01), general health perceptions (38 ± 17 to 48 ± 15, P < 0.01), and symptoms/problems (75 ± 21 to 84 ± 13, P = 0.02), compared to baseline. For intradialytic symptoms, dyspnea during HD significantly improved after the CA in the HD patients without AF recurrence (43% to 7%, P = 0.04), whereas the atrial tachyarrhythmias and hypotension during HD remained unchanged. During the follow-up period of 17 ± 13 months after the last procedure, the incidence of being arrhythmia-free was similar (HD patients, 79% vs non-HD patients, 86%, log-rank P = 0.82). No life-threatening complications occurred in any of the patients. Conclusions: CA of AF improves QoL in patients undergoing chronic HD therapy.

DOI： 10.1016/j.cjco.2022.05.009

PubMed

researchmap

記述言語：日本語   出版者・発行元：(一社)日本心臓病学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本心臓病学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijcha.2022.101074

PubMed

researchmap

記述言語：英語  

DOI： 10.1007/s00380-022-02138-4

PubMed

researchmap

記述言語：英語  

DOI： 10.1007/s00380-022-02137-5

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1253/circj.CJ-22-0285

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Atrioventricular Block (AVB) is one of the common manifestations in cardiac sarcoidosis (CS). Although pacemaker implantation is generally recommended in patients with CS complicated by symptomatic AVB, some case reports have shown that they can be managed by steroid therapy without pacemaker implantation. The aim of this study was to evaluate the feasibility and effectiveness of steroid therapy without pacemaker implantation in patients with CS complicated by symptomatic AVB. We performed medical record review of consecutive ten CS patients who admitted Nippon Medical School Hospital for symptomatic second or third degree AVB between April 2015 and March 2021. Of the studied population, steroid therapy before pacemaker implantation was feasible in three patients with second degree AVB. Two of them showed subsequent recovery of atrioventricular conduction to 1:1, and they were managed by steroid therapy without pacemaker. The remaining one patient showed no improvement of atrioventricular conduction and required pacemaker implantation. Seven patients with third degree AVB required device implantation (pacemaker; n = 7, cardiac resynchronization therapy defibrillator; n = 1) before steroid therapy mainly because of hemodynamic instability. Steroid therapy without pacemaker implantation might be feasible, and possibly be effective in patients with CS presenting second degree AVB. However, the feasibility is limited in patients with third degree AVB.

DOI： 10.1007/s00380-022-02092-1

PubMed

researchmap

記述言語：英語  

A 42-year-old man was admitted for recurrent atrioventricular reciprocating tachycardia. We performed a total activation mapping, which included a range from the ventricular to atrial waves during right ventricular pacing. The mapping revealed a delayed ventriculoatrial conduction on the left lateral wall. We performed ablation within the coronary sinus, and the ventriculoatrial conduction was lost. By widening the range, we could easily visualize the ventriculoatrial conduction through the accessory pathway. This mapping showed that the conduction in the area of the accessory pathway was delayed, and it was easy to estimate that the conduction pathway included the coronary sinus.

DOI： 10.1111/anec.12961

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1253/circj.CJ-20-1212

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Pericardiocentesis is an essential procedure for the diagnosis and treatment of pericardial effusions. The purpose of this study was to evaluate the feasibility and safety of a subxiphoid anterior approach using fluoroscopy aided by a sagittal axis chest computed tomography (CT) view in comparison with an ultrasound-guided apical approach in patients with chronic pericardial effusion. METHODS: Among 72 consecutive patients (68.8 ± 14.4 years old, 52 males) with hemodynamically stable chronic pericardial effusions, a total of 85 procedures were retrospectively analyzed. We divided them into two groups according to the site of the approach for the pericardiocentesis. RESULTS: A subxiphoid anterior approach (n = 53) was performed guided by fluoroscopy. The sagittal axis view of the chest CT was constructed to determine the puncture angle and direction for the subxiphoid anterior approach. An apical approach (n = 32) was performed by ultrasound guidance. The success rates of the anterior and apical approaches were 98.1% and 93.8%, respectively. There were two cases with cardiac perforations in the apical approach group, while no cases developed perforations in the subxiphoid anterior approach group. CONCLUSION: The subxiphoid anterior approach for pericardiocentesis was feasible and safe for managing chronic pericardial effusions. A reconstruction of the sagittal axis view of the chest CT imaging was helpful to identify the direction and depth to access the pericardial space from the subxiphoid puncture site before the pericardiocentesis using the lateral fluoroscopic view.

DOI： 10.1002/clc.23810

PubMed

researchmap

記述言語：英語  

DOI： 10.1007/s10840-022-01161-9

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Excess psychological stress is one of the precipitating factors for paroxysmal atrial fibrillation (AF), although the involved mechanisms are still uncertain. To test a hypothesis that one of the stress-induced hormones, glucocorticoid, is involved in the pathogenesis of stress-induced AF, we investigated whether the glucocorticoid could alter the temporal profile of cardiac ion channels gene expression, thereby leading to atrial arrhythmogenesis.Dexamethasone (DEX, 1.0 mg/kg) was injected subcutaneously in Sprague-Dawley rats. At predetermined times after DEX injection (0, 1, 3, 6, 12, and 24 hours), the mRNA levels of cardiac ion channel genes (erg, KvLQT1, Kv4.3, Kv4.2, Kv2.1, Kv1.5, Kv1.4, Kv1.2, SUR2A, Kir6.2, Kir3.4, Kir3.1 Kir2.2, Kir2.1, SCN5A, and α1C) were determined using RNase protection assay. DEX induced immediate and transient increase in the mRNA level of Kv1.5 and Kir2.2 with peaks at 6 (5.0 fold) and 3 hours (3.3 fold) after DEX injection, respectively. Patch-clamp studies revealed a significantly increased current density of the corresponding current, IKur and IK1 at 6 hours after DEX injection. Simultaneously, electrophysiological study in isolated perfused hearts showed significantly increased number of repetitive atrial responses induced by single atrial extrastimulus (3.2 ± 2.4 to 26.7 ± 16.4, P = 0.004) with shorting of the refractory period (36.4 ± 4.6 to 27.4 ± 5.5 ms, P = 0.049) after DEX injection.Glucocorticoid immediately modified Kv1.5 and Kir2.2 gene expression at pretranslational levels, thus leading to effective refractory period shortening that could be arrhythmogenic. These results implied that transient glucocorticoid-induced biochemical modification of cardiac ion channels might be one of the mechanisms underlying the stress-induced paroxysmal AF.

DOI： 10.1536/ihj.21-677

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

We have previously reported that atrial endocardial remodeling is induced by atrial fibrillation (AF), and the endocardial dysfunction may be partly responsible for the thrombus formation in the left atrium associated with AF. However, the relationship between the endocardial dysfunction and the epidemiologically determined risk factors of AF-related strokes, including aging, hypertension, and diabetes mellitus, is yet to be elucidated.To test the hypothesis that aging, hypertension, and diabetes mellitus individually impair the atrial endocardial function in conjunction with AF, we have analyzed the expression of the tissue factor pathway inhibitor (TFPI) and thrombomodulin (TM) in the atrial endocardium in 30-week-old Wister-Kyoto (WKY), 60-week-old WKY, 30-week-old spontaneously hypertensive rats (SHR), and 30-week Goto-Kakizaki (GK) rats during normal sinus rhythm and after rapid atrial pacing at 1200 bpm for 8 hours, using Western blotting and immunohistochemical analysis. Even during sinus rhythm, the TFPI and TM expressions were noted to be remarkably downregulated in the atrial endocardium among 60-week-old WKY rats. In contrast, in SHR rats, only the TFPI expression has significantly decreased, while TM was preserved to the same level of control 30-week-old WKY rats. Rapid atrial pacing significantly reduced the TM and TFPI expression similarly in each model, thereby augmenting the endocardial dysfunction during normal sinus rhythm individually induced by the risk factors themselves prior to AF.Aging and hypertension, both of which are epidemiologically well-known risk factors for strokes in AF, have been associated with a specific atrial endocardial impairment prior to AF that could additionally disturb the antithrombotic function of the atrial endocardium.

DOI： 10.1536/ihj.21-409

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Sustained ventricular tachycardia (sVT), leading to sudden cardiac death, is one of the common manifestations in cardiac sarcoidosis (CS). Although late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) has been reported to be associated with sVT, the relationships of its localization to sVT have not been fully evaluated.To evaluate the localization of LGE and its relationships to sVT in patients with CS, we reviewed medical record of consecutive 31 patients with CS who underwent CMR. The localization of LGE was divided into four categories: Left ventricular (LV) septum, LV free wall, right ventricular (RV) septum, and RV free wall. We investigated the association of sVT with localization of LGE and other parameters including serum biomarkers LV ejection fraction on echocardiography and Fluorine-18-fluorodeoxyglucose (FDG) accumulation on positron emission tomography (PET) -CT.Of the studied population, 8 patients (25.8%) were known to present with sVT among 31 CS patients. LGE was observed in the RV free wall in 6 patients with sVT, whereas it was in 5 patients without sVT (75.0% versus 21.7%, P = 0.022). Univariate analysis showed that only LGE in the RV free wall was associated with sVT (odds ratio [OR]: 10.80; 95% confidence interval [CI]: 1.64-70.93, P = 0.013).LGE in the RV free wall was associated with sVT in patients with CS.

DOI： 10.1536/ihj.21-635

PubMed

researchmap

掲載種別：研究論文（学術雑誌）   出版者・発行元：Japanese Society of Internal Medicine  

DOI： 10.2169/internalmedicine.8220-21

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The Japanese Catheter Ablation (J-AB) registry, started in August 2017, is a voluntary, nationwide, multicenter, prospective, observational registry, performed by the Japanese Heart Rhythm Society (JHRS) in collaboration with the National Cerebral and Cardiovascular Center using a Research Electronic Data Capture system. The purpose of this registry is to collect the details of target arrhythmias, the ablation procedures, including the type of target arrhythmias, outcomes, and acute complications in the real-world settings. During the year of 2019, we have collected a total of 80 795 procedures (mean age of 65.2 years and 66.4% male) from 425 participant hospitals. Detailed data are shown in Figures and Tables.

DOI： 10.1002/joa3.12640

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Attempting to minimize radiation exposure during catheter ablation of atrial fibrillation (AF) for patients, operators and medical staffs should be performed. This study aimed to investigate the feasibility and safety of a metal interference alert guided septal approach using 3 intracardiac echocardiography viewing positions for near-zero fluoroscopy AF ablation procedures. Methods/results: A total of 668 procedures among 608 consecutive patients with AF (67.2 ± 7.3 years, 408 males) who underwent catheter ablation were retrospectively evaluated and divided into 2 groups, near-zero group (n = 42) and conventional group (n = 595). In the near-zero group, a metal interference alert guided septal approach with 3 different catheter intracardiac echocardiography positions to minimize the fluoroscopy time was applied, and a left atrial access with 2 long sheaths from a single septal puncture without fluoroscopy was successfully achieved in 41 out of 42 cases. The total fluoroscopy time was significantly shorter in the near-zero group than that in the conventional group (0.5 ± 2.0 vs. 21.4 ± 12.9 min p < 0.0001). The total procedure time and time to the septal puncture were both significantly longer in the near-zero group than those in the conventional group (131.4 ± 40.2 vs. 116.6 ± 46.4p = 0.0453, 31.6 ± 9.2 vs. 19.9 ± 10.2 min, p < 0.0001), The ablation time did not differ between the 2 groups (Near-zero: 99.8 ± 41.0 vs. Conventional: 96.8 ± 44.3 min, p = 0.6663). There were no significant differences in the complication rate between the 2 groups (Near-zero: 0 vs. Conventional 14 case, p = 0.6151). Conclusion: A metal interference alert guided septal approach using 3 intracardiac echocardiography viewing positions was feasible and safe for a near-zero fluoroscopy catheter ablation of AF.

DOI： 10.1016/j.ijcha.2021.100896

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

PURPOSE: Catheter ablation (CA) is an established treatment for atrial fibrillation (AF). Although coronary artery spasms (CAS) during or after ablation procedures have been described as a rare complication in some case reports, the incidence and characteristics of this complication have not been fully elucidated. The present observational study aimed to clarify the CAS in a large number of patients experiencing AF ablation. METHODS: A total of 2913 consecutive patients (male: 78%, mean 66 ± 10 years) who underwent catheter ablation of AF were enrolled. RESULTS: Nine patients (0.31%, mean 66 ± 10 years, 7 males) had transient ST-T elevation (STE). Eight out of the 9 patients had STE in the inferior leads. STE occurred after the transseptal puncture in 7 patients, after the sheath was pulled out of the left atrium in 1, and 2 h after the ablation procedure in 1. Six patients had definite angiographic CAS without any sign of an air embolization on the emergent coronary angiography. In the3 other patients, the STE improved either directly after an infusion of nitroglycerin or spontaneously before the CAG. The patients with CAS had a higher frequency of a smoking habit (89% vs. 53%; P = .04), smaller left atrial diameter (36 ± 6 vs. 40 ± 7; P = .07), and lower CHADS2 score (0.6 ± 0.5 vs. 1.3 ± 1.1; P = .004) than those without. CONCLUSIONS: Although the incidence was rare (0.31%), CAS should be kept in mind as a potentially life-threatening complication throughout an AF ablation procedure especially performed under conscious sedation.

DOI： 10.1007/s10840-021-01089-6

PubMed

researchmap

記述言語：日本語   出版者・発行元：(公財)日本心臓財団  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Atrial flutter (AFL) is a large reentrant circuit located in the right atrium. Anti-arrhythmic drugs (AADs) can provoke AFL with 1:1 atrioventricular conduction (AVC) to cause hemodynamic collapse. We elucidated the characteristics of patients with AFL exhibiting spontaneous 1:1 AVC. Fifteen patients (1:1 AFL group; 11 males, 52.4 ± 13.7 years old) who documented AFL with 1:1 AVC were enrolled and compared to 153 patients without 1:1 AVC (Control group; 137 males, 68.9 ± 11.2 years old). AFL cycle length during maximum AVC was significantly longer in the 1:1 AFL group than in the control group (274.7 ± 37.0 vs. 216.2 ± 25.6 ms, p < 0.001). Among 1:1 AVC group, 9 patients had AADs, and AFL cycle length was significantly longer during 1:1 AVC as compared with 2:1 AVC documented the other day (284.4 ± 41.3 vs. 233.3 ± 26.0 ms, p < 0.001), suggesting enhancement effect of the AADs during 1:1 AVC. Remaining 6 patients who did not take AADs, 2 patients showed enlargement of the tricuspid annulus and 3 patients developed 1:1 AVC during exercise. Multivariate analysis revealed that younger age and the use of AADs was independent risk factors for the development of 1:1 AFL group. Prolonged AFL cycle length associated with the class Ia/Ic AAD use, slower heart rate during sinus rhythm and younger age were important risk factors for the development of 1:1 AVC during AFL.

DOI： 10.1007/s00380-021-01968-y

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Few studies have investigated the clinical benefit of the long-term use of tolvaptan (TLV) for heart failure (HF). This study evaluated the long-term prognosis of patients administered TLV for > 1 year among patients who had HF with preserved ejection fraction (HFpEF) and those who had HF with reduced ejection fraction (HFrEF). Overall, 591 consecutive patients were admitted to our hospital and administered TLV for HF between 2011 and 2018. We retrospectively enrolled 147 patients who were administered TLV for > 1 year. We divided them into the HFpEF group (n = 77, 52.4%) and the HFrEF group (n = 70; 47.6%). Their clinical backgrounds and long-term prognosis were examined. Compared with the patients in the HFrEF group, the patients in the HFpEF group were significantly older and included more women. Moreover, the HFpEF group showed significantly lower all-cause mortality (38.6% vs. 24.7%; log-rank, P = 0.014) and cardiovascular mortality during the average 2.7-year follow-up. Univariate analysis revealed that all-cause mortality was correlated with male sex, HFpEF, and changes in serum creatinine levels from baseline. Multivariate analysis revealed that HFpEF was an independent influencing factor for all-cause mortality (hazard ratio, 0.44; 95% confidence interval, 0.23-0.86; P = 0.017). Long-term administration of TLV may be more beneficial for HFpEF than for HFrEF.

DOI： 10.1007/s00380-021-01957-1

PubMed

researchmap

記述言語：日本語   出版者・発行元：日本医科大学医学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1253/circj.CJ-21-0431

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.cardfail.2021.04.023

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The impact of catheter ablation for atrial fibrillation (AF) on cardiovascular events and mortality is controversial. We investigated the impact of sinus rhythm maintenance on major adverse cardiac and cerebrovascular events after AF ablation from a Japanese multicenter cohort of AF ablation. We investigated 3326 consecutive patients (25.8% female, mean age 63.3 ± 10.3 years) who underwent catheter ablation for AF from the atrial fibrillation registry to follow the long-term outcomes and use of anti coagulants after ablation (AF frontier ablation registry). The primary endpoint was a composite of stroke, transient ischemic attack, cardiovascular events, and all-cause death. During a mean follow-up of 24.0 months, 2339 (70.3%) patients were free from AF after catheter ablation, and the primary composite endpoint occurred in 144 (4.3%) patients. The AF nonrecurrence group had a significantly lower incidence of the primary endpoint (1.8 per 100 person-years) compared with the AF recurrence group (3.0 per 100 person-years, p = 0.003). The multivariate analysis revealed that freedom from AF (hazard ratio 0.61, 95% confidence interval 0.44-0.86, p = 0.005) was independently associated with the incidence of the composite event. In the multicenter cohort of AF ablation, sinus rhythm maintenance after catheter ablation was independently associated with lower rates of major adverse cardiac and cerebrovascular events.

DOI： 10.1007/s00380-021-01929-5

PubMed

researchmap

記述言語：日本語   出版者・発行元：(一社)日本心臓病学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本心臓病学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: The clinical course and therapeutic strategies in the congenital long QT syndrome (LQTS) are genotype-specific. However, accurate estimation of LQTS genotype is often difficult from the standard 12-lead ECG. OBJECTIVES: This study aims to evaluate the utility of QT/RR slope analysis by the 24-hour Holter monitoring for differential diagnosis of LQTS genotype between LQT1 and LQT2. METHODS: This cross-sectional study enrolled 54 genetically identified LQTS patients (29 LQT1 and 25 LQT2) recruited from three medical institutions. The QT-apex (QTa) interval and the QT-end (QTe) interval at each 15-second were plotted against the RR intervals, and the linear regression (QTa/RR and QTe/RR slopes, respectively) was calculated from the entire 24-hour and separately during the day or night-time periods of the Holter recordings. RESULTS: The QTe/RR and QTa/RR slopes at the entire 24-hour were significantly steeper in LQT2 compared to those in LQT1 patients (0.262 ± 0.063 vs. 0.204 ± 0.055, p = .0007; 0.233 ± 0.052 vs. 0.181 ± 0.040, p = .0002, respectively). The QTe interval was significantly longer, and QTe/RR and QTa/RR slopes at daytime were significantly steeper in LQT2 than in LQT1 patients. The receiver operating curve analysis revealed that the QTa/RR slope of 0.211 at the entire 24-hour Holter was the best cutoff value for differential diagnosis between LQT1 and LQT2 (sensitivity: 80.0%, specificity: 75.0%, and area under curve: 0.804 [95%CI = 0.68-0.93]). CONCLUSION: The continuous 24-hour QT/RR analysis using the Holter monitoring may be useful to predict the genotype of congenital LQTS, particularly for LQT1 and LQT2.

DOI： 10.1111/anec.12878

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

INTRODUCTION: Plasma volume status (PVS), a parameter of the discrepancy between actual plasma volume (PV) and ideal PV, has been recently evaluated as a prognostic marker in patients with heart failure. This subgroup analysis of the EMBODY trial was designed to determine whether a sodium-glucose cotransporter 2 (SGLT2) inhibitor affects the alleviation of heart failure and improvement of PVS in patients after acute myocardial infarction (AMI) with congestive heart failure (CHF). METHODS: The EMBODY trial was a prospective, multicenter, randomized, double-blind, placebo-controlled trial to identify the effect of an SGLT2 inhibitor on cardiac sympathetic hyperactivity in patients with AMI and type 2 diabetes mellitus (T2DM) in Japan. In total, 105 patients were randomized (1:1) to receive 10 mg empagliflozin or a placebo (once daily), 2 weeks after the onset of AMI. In this subanalysis, we investigated the time-course of PVS at baseline and weeks 4, 12, and 24. RESULTS: Overall, 96 patients were included in the subgroup analysis set (age 64.3 ± 10.9 years, 80.2% men; 46 in the empagliflozin group and 50 in the placebo group). Body weight and PVS decreased in the empagliflozin group compared with the placebo group at 24 weeks (- 2.2 vs. + 0.1 kg, P < 0.001, and - 5.1 vs. - 0.3%, P < 0.001, respectively). Decreased PVS, defined as a change in PVS of < - 4.5%, was associated with the administration of empagliflozin (odds ratio 2.61, 95% confidence interval 1.11-6.15, P = 0.028). N-terminal pro b-type natriuretic peptide levels decreased in both the empagliflozin and placebo groups (1028.7-370.3 pg/mL, P < 0.001, and 1270.6-673.7 pg/mL, P < 0.01, respectively). CONCLUSION: Empagliflozin reduced the body weight and PVS. Early SGLT2 inhibitor administration in patients with AMI, CHF, and T2DM can therefore be effective in reducing the body weight and PVS. TRIAL REGISTRATION: UMIN 000030158.

DOI： 10.1007/s13300-021-01103-0

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

AIMS: Although the reno-protective effects of sodium-glucose cotransporter 2 inhibitors are known in patients with heart failure or type 2 diabetes mellitus (T2DM), this effect has not been confirmed in patients with acute myocardial infarction (AMI). METHODS AND RESULTS: The prospective, multicentre, randomized, double-blind, placebo-controlled EMBODY trial investigated patients with AMI and T2DM in Japan. The eligible patients included adults aged 20 years or older, diagnosed with AMI and T2DM, and who could be discharged within 2-12 weeks after the onset of AMI. One hundred and five patients were randomized (1:1) to receive once daily 10 mg empagliflozin or placebo within 2 weeks of AMI onset. In this sub-analysis, we investigated the time course of renal functional parameters such as serum creatinine levels and estimated glomerular filtration rate (eGFR) from baseline to Weeks 4, 12, and 24. Ninety-six patients (64 ± 11 years, 78 male) were included in the full analysis (n = 46 and 50 in the empagliflozin and placebo groups, respectively). We used serum creatinine and eGFR as indicators of renal function. In the placebo group, eGFR decreased from 66.14 mL/min/1.73 m2 at baseline to 62.77 mL/min/1.73 m2 by Week 24 (P = 0.023) but remained unchanged in the empagliflozin group (from 64.60 to 64.36 mL/min/1.73 m2 , P = 0.843). In the latter group, uric acid improved from 5.8 mg/dL at baseline to 4.9 mg/dL at Week 24 (P < 0.001). In the earlier analysis of 56 patients with eGFR ≥ 60 mL/min/1.73 m2 , the eGFR decreased and the serum creatinine increased from baseline to 24 weeks in the placebo group, significantly different to the empagliflozin group (-6.61 vs. +0.22 mL/min/1.73 m2 , P = 0.008 and +0.063 vs. -0.001 mg/dL, P = 0.030, respectively). The changes in serum creatinine and eGFR from baseline to Week 24 were significantly correlated with those in uric acid in the placebo group (r = 0.664, P < 0.001 and r = -0.675, P < 0.001, respectively) but not in the empagliflozin group. CONCLUSIONS: Empagliflozin prevented the kidney functional decline in patients with AMI and T2DM, especially those with baseline eGFR ≥ 60 mL/min/1.73 m2 . Early administration of sodium-glucose cotransporter 2 inhibitors in these patients is considered desirable for renal protection.

DOI： 10.1002/ehf2.13509

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: It is unclear whether there are differences in the clinical factors between atrial fibrillation (AF) recurrence and adverse clinical events (AEs), including stroke/transient ischemic attack (TIA), major bleeding, and death, after AF ablation.Methods and Results:We examined the data from a retrospective multicenter Japanese registry conducted at 24 cardiovascular centers between 2011 and 2017. Of the 3,451 patients (74.1% men; 63.3±10.3 years) who underwent AF ablation, 1,046 (30.3%) had AF recurrence and 224 (6.5%) suffered AEs (51 strokes/TIAs, 71 major bleeding events, and 36 deaths) over a median follow-up of 20.7 months. After multivariate adjustment, female sex, persistent and long-lasting persistent AF (vs. paroxysmal AF), and stepwise increased left atrial diameter (LAd) quartiles were significantly associated with post-ablation recurrences. A multivariate analysis revealed that an age ≥75 years (vs. <65 years), body weight <50 kg, diabetes, vascular disease, left ventricular (LV) ejection fraction <40% (vs. ≥50%), Lad ≥44 mm (vs. <36 mm), and creatinine clearance <50 mL/min were independently associated with AE incidences, but not with recurrences. CONCLUSIONS: This study disclosed different determinants of post-ablation recurrence and AEs. Female sex, persistent AF, and enlarged LAd were determinants of post-ablation recurrence, whereas an old age, comorbidities, and LV and renal dysfunction rather than post-ablation recurrence were AEs determinants. These findings will help determine ablation indications and post-ablation management.

DOI： 10.1253/circj.CJ-21-0326

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1253/circj.CJ-20-0637

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Right ventricular (RV) pacing causes changes in the heart's electrical and mechanical activation patterns. The QRS duration is a useful surrogate marker of electrical dyssynchrony; a longer QRS duration during RV pacing indicates poor prognosis. However, the mechanisms underlying a longer QRS duration during RV pacing remain unclear; hence, we investigated factors predicting QRS prolongation during RV pacing. We enrolled 211 patients who underwent catheter ablation for supraventricular tachyarrhythmia and showed no bundle branch block. Three-dimensional mapping for the QRS duration during RV pacing from the RV outflow to RV apex was performed, and differences in the QRS duration were analyzed. The predisposing factors causing QRS > 160 ms during RV apical pacing were also analyzed. The QRS durations at baseline and during RV pacing from the RV outflow and at the RV apex were 85.0 ± 7.5 ms, 163.7 ± 17.1 ms, and 156.2 ± 16.1 ms, respectively. With respect to the QRS duration, there was a significant correlation between RV outflow and RV apical pacing (r = 0.658, p < 0.001). Difference in the QRS duration between the RV outflow and RV apex in each patient was only 12.5 ± 10.4 ms. Logistic multivariable regression analysis identified baseline QRS duration [odds ratio (OR) 1.24, 95% confidence interval (CI) 1.15-1.33, p < 0.01], interventricular septum thickness (OR 1.20, 95% CI 1.02-1.40, p = 0.025), left atrial diameter (OR 1.08, 95% CI 1.01-1.16, p = 0.024), and E/e' (OR 1.23, 95% CI 1.12-1.35, p < 0.01) as significant predictors of QRS prolongation during RV apical pacing. The QRS duration during RV pacing largely depends not on the pacing site, but on the underlying structural heart diseases.

DOI： 10.1007/s00380-021-01881-4

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Respiratory management during catheter ablation of atrial fibrillation (AF) is important for the efficacy and safety of the procedure. Obstructive apnea due to an upper airway obstruction might cause serious complications including air embolisms and cardiac tamponade. However, real time monitoring of upper airway obstructions during catheter ablation has not been established. The purpose of the present study was to evaluate esophageal pressure monitoring for respiratory management during catheter ablation of AF. Methods and Results: Twenty-four consecutive patients (20 men and 4 women; mean age, 61 ± 13 years) with AF who underwent esophageal pressure monitoring during catheter ablation of AF were retrospectively analyzed. The patients were divided into 2 groups. One was the obstructive apnea (OA) group (n = 17), which required airway management tools including nasal airways and/or non-invasive positive airway pressure (NPPV) and the other was the control group (n = 7), which did not require airway management. Esophageal pressure measurements were obtained in all patients, and the OA group exhibited a substantial negative esophageal pressure as compared to the control group (-41.48 ± 19.58 vs. -12.42 ± 5.77 mmHg, p < 0.001). Airway management in the OA group immediately improved the negative esophageal pressure and returned to a normal range (-41.48 ± 19.58 vs. -16 ± 8.1 mmHg, 0 < 0.001) along with a recovery from desaturation. Conclusions: Esophageal pressure monitoring was a simple and effective method for the evaluation and management of obstructive apnea during AF catheter ablation.

DOI： 10.1016/j.ijcha.2021.100771

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Whether ablation for atrial fibrillation (AF) is, in terms of clinical outcomes, beneficial for Japanese patients has not been clarified. Drawing data from 2 Japanese AF registries (AF Frontier Ablation Registry and SAKURA AF Registry), we compared the incidence of clinically relevant events (CREs), including stroke/transient ischemic attack (TIA), major bleeding, cardiovascular events, and death, between patients who underwent ablation (n = 3451) and those who did not (n = 2930). We also compared propensity-score matched patients (n = 1414 in each group). In propensity-scored patients who underwent ablation and those who did not, mean follow-up times were 27.2 and 35.8 months, respectively. Annualized rates for stroke/TIA (1.04 vs. 1.06%), major bleeding (1.44 vs. 1.20%), cardiovascular events (2.15 vs. 2.49%) were similar (P = 0.96, 0.39, and 0.35, respectively), but annualized death rates were lower in the ablation group than in the non-ablation group (0.75 vs.1.28%, P = 0.028). After multivariate adjustment, the risk of CREs was statistically equivalent between the ablation and non-ablation groups (hazard ratio [HR] 0.89, 95% confidence interval [CI] 0.71-1.11), but it was significantly low among patients who underwent ablation for paroxysmal AF (HR 0.68 [vs. persistent AF], 95% CI 0.49-0.94) and had a CHA2DS2-VASc score  < 3 (HR 0.66 [vs. CHA2DS2-VASc score ≥ 3], 95% CI 0.43-0.98]). The 2-year risk reduction achieved by ablation may be small among Japanese patients, but AF ablation may benefit those with paroxysmal AF and a CHA2DS2-VASc score < 3.

DOI： 10.1007/s00380-020-01721-x

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Early detection of cardiac involvement in patients with sarcoidosis is important but currently unresolved. The aim of this study was to elucidate the utility of frequency domain microvolt T-wave alternans (TWA), signal-averaged ECG (SAECG), and heart rate turbulence (HRT) using 24-hour Holter ECG for detecting cardiac involvement in patients with pulmonary sarcoidosis. Methods: This study consisted of consecutive 40 pulmonary sarcoidosis patients (11 males, 62 ± 13 years) who underwent 24-hour Holter monitoring with and without cardiac involvement. All patients underwent frequency domain TWA, SAECG, and HRT using 24-hour Holter monitoring. Patients with atrial fibrillation pacing or wide QRS electrocardiogram were excluded. Results: After 14 patients were excluded, a total of 26 patients (six males, 59 ± 14 years) were evaluated. Seven patients had cardiac involvement (cardiac sarcoidosis [CS] group). On the Holter SAECG, duration of low-amplitude signals <40 μV in the terminal filtered QRS complex (LAS40) was significantly higher, and root mean square voltage of the terminal 40 ms of the filtered QRS complex (RMS40) was significantly lower in the CS group compared with the non-CS group (LAS40: 61.4 ± 35.9 vs 37.6 ± 9.2 ms; P = .018, RMS40: 11.4 ± 10.3 vs 23.6 ± 13.2 ms; P = .023). Prevalence of positive late potential (LP) was also significantly higher in the CS group than that in the non-CS group (85.7% vs 31.5%; P = .026). The sensitivity, specificity, positive, and negative predictive values of LP for identifying patients with cardiac involvement were 85.7%, 68.4%, 50.0%, and 92.8%, respectively. Conclusion: Holter SAECG may be useful for detecting cardiac involvement in patients with pulmonary sarcoidosis.

DOI： 10.1002/joa3.12501

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

INTRODUCTION: Although antitachycardia pacing (ATP) is effective in terminating ventricular tachyarrhythmias in patients with implantable cardioverter defibrillators (ICDs), the efficacy of ATP during an electrical storm (ES) and the positive impact on all-cause mortality have not been fully elucidated. METHODS AND RESULTS: From 2010 to 2012, 1570 patients who underwent ICD implantation in 48 ICD centers in Japan were enrolled in the study and prospectively followed up. Patients with long QT syndrome, Brugada syndrome, and idiopathic ventricular fibrillation were excluded. The prevalence of shocks during ESs and impact on the all-cause mortality were evaluated. During a median follow-up of 28 months, there were 127 ESs in 84 patients. Of those 127 ESs, 80 ESs (63%) in 37 patients were treated by only ATP and the remaining 47 ESs in 47 patients required at least one shock. The lower ventricular rate of the initial arrhythmia during ES (odds ratio [OR]: 1.02 per unit; 95% confidence interval [CI]: 1.00-1.04; p = .02) and narrower QRS complex (OR: 1.03 per unit; 95% CI: 1.01-1.06; p < .01) were the independent predictors of ATP success during the ES. The patients treated with ATP alone tended to have lower all-cause mortality compared to those that required shocks during the ES (log-rank p = .10). CONCLUSIONS: ATP was effective in patients suffering from ESs as it avoided painful shocks in more than half of the cases. Patients who received only ATP during ES tended to have lower mortality compared to those who received the shock.

DOI： 10.1111/jce.14891

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Although epicardial structures around the atrium such as adipose tissue possess arrhythmogenicity, little is known about atrial tachycardias (ATs) originating from epicardial sites (Epi-ATs). This study aimed to elucidate the prevalence, characteristics, and outcome after radiofrequency catheter ablation (RFCA) of Epi-ATs and to reveal the association between Epi-ATs and the epicardial structures. METHODS: The electrocardiographic, electrophysiologic, and anatomical properties and results of RFCA were analyzed in 42 patients with a total of 49 ectopic ATs. RESULTS: Six Epi-ATs (12%) were observed in six patients (14%). Four of six were respiratory cycle-dependent ATs and one was a swallowing-induced AT. The Epi-AT origins were adjacent to a pulmonary vein (five cases) and vein of Marshall (one case). A Valsalva maneuver or atropine infusion to define the arrhythmia mechanism affected the appearance of the Epi-ATs. The congruity rate between epicardial adipose tissue and the AT origin was significantly higher (100% vs. 44%, p = .045), and the epicardial adipose tissue volume of the atrium was significantly larger (104.1 vs. 64.6 ml, p = .04) in the Epi-AT group. Endocardial RFCA targeting the AT foci resulted in acute success in five of five cases. However, electrical isolation including of the AT foci resulted in acute failures (two of three cases) or a recurrence (one of one case). CONCLUSIONS: Six Epi-ATs were associated with thoracic veins and epicardial arrhythmogenic structures. The main cause provoking the Epi-ATs was associated with autonomic nerve activity.

DOI： 10.1002/clc.23577

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Although implantable cardioverter defibrillators (ICDs) are a powerful preventive therapy for cardiac sudden death, there are some populations in whom ICDs cannot be applied because of a lack of a definitive indication (grey-zone patients), such as in patients during the acute phase of cardiac injury with a susceptible risk for lethal arrhythmias. In such patients, wearable cardioverter defibrillators (WCDs) provide safer bridging period during the acute phase until the final decision-making for the ICD use and it may eliminate any inappropriate overuse of ICDs in the subacute phase. The JCS/JHRS practical guidelines provide the criteria for WCD use in Japan. Nevertheless, the evidence for that is totally limited in Japan and is dependent on the accumulation of actual real-world data from other countries in order to be able to discuss the appropriate criteria for WCD use. This study will be conducted retrospectively and/or prospectively, and is an observational and multicenter study among Japanese institutions (J-WCDR, Japan WCD Registry). This will provide evidence for WCD use in our own country and contribute to upcoming updates for the future guideline revisions.

DOI： 10.1002/joa3.12456

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/joa3.12419

PubMed

researchmap

記述言語：英語  

DOI： 10.1016/j.hrcr.2020.09.014

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Atrial fibrillation (AF) is the most common arrhythmia in patients with hypertrophic cardiomyopathy (HCM). The present study aimed to investigate the incidence and prognostic impact of newly detected AF after cardiac implantable electronic device (CIED) implantation with HCM patients. Fifty-six patients (33 men, age 57 ± 17 years) with HCM who underwent CIED implantations with no previous history of AF at the time of implantation (ICD n = 46, Pacemaker n = 10) were retrospectively enrolled. During 5.7 ± 3.6 years of follow-up, AF was newly detected in 20 (36%) of 56 patients after the CIED implantation (AF group) and the rest of the patients had no newly detected AF (non-AF group). The presence of mitral regurgitation (HR 8.49; 95% CI 2.29-30.6 P < 0.01) and concomitant NYHA II-IV (HR 3.37; 95% CI 1.30-8.86 P = 0.01) were the independent predictors of newly detected AF. During the follow-up, all patients in the AF group started anticoagulation mean 21 days after detection of AF, and none had a stroke during the follow-up period. The rate of appropriate ICD therapy (log-rank P = 0.95), inappropriate ICD therapy (log-rank P = 0.78), and all-cause death (log-rank P = 0.23) were similar between the two groups. However, the incidence of hospitalizations due to heart failure was higher in the AF group (55% vs. 6% log-rank P < 0.01). In conclusion, the incidence of newly detected AF after CIED implantations in HCM patients was high. The newly detected AF was associated with worsening heart failure and careful follow-up is recommended.

DOI： 10.1007/s00380-020-01728-4

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Direct oral anticoagulants (DOACs) are sometimes prescribed at off-label under-doses for patients who have undergone ablation for atrial fibrillation (AF). This practice may be an attempt to balance the risk of bleeding against that of stroke or AF recurrence.We examined outcomes of 1163 patients who continued use of a DOAC after ablation. The patients were enrolled in a large (3530 patients) multicenter registry in Japan. The study patients were classified as 749 (64.4%) appropriate standard-dose DOAC users, 216 (18.6%) off-label under-dose DOAC users, and 198 (17.0%) appropriate low-dose DOAC users.Age and CHA2DS2-VASc scores differed significantly between DOAC dosing regimens, with patients given an appropriate standard-dose being significantly younger (63.3 ± 9.4 versus 64.8 ± 9.5 versus 73.2 ± 6.8 years, P < 0.0001) and lower (2.1 ± 1.5 versus 2.4 ± 1.6 versus 3.4 ± 1.4, P < 0.0001) than those given an off-label under-dose or an appropriate low-dose. During the median 19.0-month follow-up period, the AF recurrence rate was similar between the appropriate standard-dose and off-label under-dose groups but relatively low in the appropriate low-dose group (42.5% versus 41.2% versus 35.4%, P = 0.08). Annualized rates of thromboembolic events, major bleeding, and death from any cause were 0.47%, 0.70%, and 0.23% in the off-label under-dose group, while those rates were 0.74%, 0.73%, and 0.65% in the appropriate standard-dose, and 1.58%, 2.12%, and 1.57% in the appropriate low-dose groups.In conclusion, the clinical adverse event rates for patients on an off-label under-dose DOAC regimen after ablation, predicated on careful patient evaluations, was not high as seen with that of patients on a standard DOAC dosing regimen.

DOI： 10.1536/ihj.20-335

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Protection from lethal ventricular arrhythmias leading to sudden cardiac death (SCD) is a crucial challenge after acute myocardial infarction (AMI). Cardiac sympathetic and parasympathetic activity can be noninvasively assessed using heart rate variability (HRV) and heart rate turbulence (HRT). The EMBODY trial was designed to determine whether the Sodium-glucose cotransporter 2 (SGLT2) inhibitor improves cardiac nerve activity. METHODS: This prospective, multicenter, randomized, double-blind, placebo-controlled trial included patients with AMI and type 2 diabetes mellitus (T2DM) in Japan; 105 patients were randomized (1:1) to receive once-daily 10-mg empagliflozin or placebo. The primary endpoints were changes in HRV, e.g., the standard deviation of all 5-min mean normal RR intervals (SDANN) and the low-frequency-to-high-frequency (LF/HF) ratio from baseline to 24 weeks. Secondary endpoints were changes in other sudden cardiac death (SCD) surrogate markers such as HRT. RESULTS: Overall, 96 patients were included (46, empagliflozin group; 50, placebo group). The changes in SDANN were + 11.6 and + 9.1 ms in the empagliflozin (P = 0.02) and placebo groups (P = 0.06), respectively. Change in LF/HF ratio was - 0.57 and - 0.17 in the empagliflozin (P = 0.01) and placebo groups (P = 0.43), respectively. Significant improvement was noted in HRT only in the empagliflozin group (P = 0.01). Whereas intergroup comparison on HRV and HRT showed no significant difference between the empagliflozin and placebo groups. Compared with the placebo group, the empagliflozin group showed significant decreases in body weight, systolic blood pressure, and uric acid. In the empagliflozin group, no adverse events were observed. CONCLUSIONS: This is the first randomized clinical data to evaluate the effect of empagliflozin on cardiac sympathetic and parasympathetic activity in patients with T2DM and AMI. Early SGLT2 inhibitor administration in AMI patients with T2DM might be effective in improving cardiac nerve activity without any adverse events. TRIAL REGISTRATION: The EMBODY trial was registered by the UMIN in November 2017 (ID: 000030158). UMIN000030158; https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000034442 .

DOI： 10.1186/s12933-020-01127-z

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Atrial fibrillation (AF) and cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL) are 2 separate entities that coexist in a significant proportion of patients. In patients with CTI ablation of AFL, the decision to hold anticoagulation often becomes an issue. OBJECTIVES: This study aimed to describe the incidence of the development of AF after CTI ablation in patients without a history of AF and to identify the risk predictors of the occurrence of AF. METHODS: The present study included 120 consecutive patients (106 men; mean age 68 ± 12 years) who underwent radiofrequency catheter ablation (RFCA) of typical AFL since 2010. Patients with a history of AF before RFCA were excluded. The P-wave and QRS morphology, characteristics, and duration were evaluated by 12-lead electrocardiography the day after ablation. RESULTS: During 3.6 ± 2.6 years of follow-up after RFCA, 49 patients (41%) developed new-onset AF. A univariate analysis revealed that the presence of fragmented QRS (fQRS) complexes (hazard ratio [HR], 4.63; 95% confidence interval [CI] 2.31-9.29; P < .001) and advanced interatrial block (IAB), defined as P-wave duration > 120 ms and biphasic morphology in the inferior leads (HR 4.44; 95% CI 2.45-8.01; P < .001), were predictors of new-onset AF. A multivariate analysis revealed that fQRS complexes (HR 3.35; 95% CI 1.58-7.10; P = .002) and advanced IAB (HR 2.64; 95% CI 1.38-5.07; P < .004) were independent predictors. CONCLUSION: The present study indicated that new-onset AF developed in a significant proportion of patients undergoing AFL ablation. The presence of fQRS complexes and advanced IAB were predictors of new-onset AF.

DOI： 10.1016/j.hrthm.2020.04.021

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER IRELAND LTD  

Background: There is increasing evidence that a proportion of patients with cardiac sarcoidosis (CS) have atrial arrhythmias (AA). Although 18F-fluorodeoxy-glucose (FDG) uptake in the ventricle on positron emission tomography/computed tomography (PET/CT) is well studied, FDG uptake in the atrium has not been elucidated in detail.Objectives: To evaluate FDG uptake in the atrium and its relationship with AA in patients with CS. Methods: We retrospectively investigated 62 CS patients. All patients underwent echocardiography and PET/CT. Serum angiotensin converting enzyme (ACE) and soluble IL-2 receptor (sIL-2R) levels, plasma N-terminal probrain natriuretic peptide (NT-proBNP) concentrations were also evaluated. ECG, Holter monitoring and device interrogations were used to detect AA.Results: Of the studied population, 25 patients (40.3%) had AA, ofwhich 2 patients had atrial tachycardia (AT) and 23 patients had atrial fibrillation (AF). Eighteen patients with AA had atrial FDG uptake on PET/CT, whereas 14 patients without AA had atrial FDG uptake (72.0% vs 37.8%, P = 0.017). Multivariate analysis revealed a significant association between AA and age (odds ratio [OR]: 1.15; 95% confidence interval [CI]: 1.01-1.31, P= 0.040), atrial FDG uptake (odds ratio [OR]: 7.23; 95% confidence interval [CI]: 1.91-27.36, P = 0.004), and left atrial diameter (OR: 1.08; 95% CI: 1.01-1.16, P= 0.027). Meanwhile, gender, serumACE and BNP levels, and left ventricular ejection fraction were not associated with AA.Conclusions: Atrial FDG uptake was common in patients with CS and strongly associated with AA. (c) 2020 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ijcard.2020.04.041

Web of Science

PubMed

researchmap

記述言語：日本語   出版者・発行元：(一社)日本不整脈心電学会  

心サルコイドーシスは脚ブロックや房室ブロックなどの伝導障害で発症することが多く、伝導異常を鋭敏に反映する加算平均心電図がその早期診断に有用である可能性がある。われわれは心電図正常の肺サルコイドーシス患者74例で加算平均心電図を記録分析し、その後の心イベントとの関連性を解析した。結果、29名(39.2%)が加算平均心電図においてLP陽性であった。平均9.8年のフォローアップ期間でLP陽性例のうち8例が心イベントを発症した(完全房室ブロック4例、心室頻拍2例、心不全2例)。一方、心室遅延電位陰性群では1例のみ(心不全)であった。多変量解析の結果、LPのみが独立した危険因子であった(ハザード比9.66、95%信頼区間1.20-78.01、p=0.033)。Kaplan-Meier法を用いた解析では、LP陽性患者は陰性患者に比し有意に心イベントを起こしやすい(log-lank、p=0.004)ことが判明した。以上の結果から、肺サルコイドーシスにおける心室遅延電位は、心イベントの早期予測に有用である可能性が示唆された。(著者抄録)

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Signal-averaged electrocardiography (SAECG) has been known to be useful for prediction of lethal ventricular arrhythmias (VA). However, this technique has limitations in patients with intraventricular conduction disturbance (IVCD), which is common in cardiac sarcoidosis (CS). Meanwhile, wavelet-transformed ECG (WTECG) has been reported to be useful for detecting arrhythmogenic substrate hidden within QRS complex. The objective of this study was to assess the utility of WTECG for detecting arrhythmogenic substrate in patients with CS. Forty-four CS patients including 18 patients with VA were retrospectively investigated. The parameters on the signal-averaged electrocardiography (SAECG) and the power of frequency components on WTECG were compared between VA group and non-VA group. Eighteen patients have VA (VT: n = 17, VF: n = 1). LP were detected in 17 in VA group and 24 in non-VA group. WTECG showed that high-frequency components (HFC; 80-150 Hz) were developed in VA group. Peak power value at 150 Hz (P150) was significantly higher in VA group than that in non-VA group (442.9 ± 160.2 vs 316.7 ± 100.8, p = 0.006). The receiver operating characteristic (ROC) curve analysis showed an optimal cutoff point of 336 of P150 for detecting patients with VA, with 82.4% sensitivity, 61.5% specificity, and area under the curve of 0.74 (95% confidence interval [CI] 0.59-0.89). WTECG may be useful for detecting CS patients who are prone to VA.

DOI： 10.1007/s00380-020-01584-2

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1253/circj.CJ-20-0255

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Catheter ablation (CA) has been reported to reduce risk of stroke in patients with nonvalvular atrial fibrillation (NVAF) in retrospective studies. However, the risks and benefits of CA have not been well elucidated in patients with NVAF and who have suffered a recent ischemic stroke in prospective randomized trials. Thus, the aim of the STABLED clinical trial is to investigate the efficacy and safety of CA with anticoagulant therapy using edoxaban in patients with NVAF and a history of recent ischemic stroke. METHODS AND DESIGN: The STABLED trial is a multicenter, prospective, randomized, open-label, standard medication-controlled study in Japan. The target patient number is 250, comprising 125 patients receiving standard medication and 125 receiving CA. For patients allocated to the CA group, ablation is to be performed between 1 to 6 months from the onset of index stroke. The observation period will be 3 years from the day of random allocation of the final patient to any of the groups. The primary outcome measure is the composite of recurrence of ischemic stroke, systemic embolism, all-cause death, and hospitalization for heart failure. CONCLUSION: This study will investigate the effectiveness and safety of CA and basic anticoagulation treatment with edoxaban for patients with NVAF who have suffered a recent ischemic stroke. The aim is to determine the best evidence for an optimal treatment strategy for patients with NVAF and recent stroke. TRIAL REGISTRATION: UMIN000031424/NCT03777631.

DOI： 10.1016/j.jjcc.2019.06.002

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: The safety of discontinuing oral anticoagulant (OAC) after ablation for atrial fibrillation (AF) in Japanese patients has not been clarified.Methods and Results:A study based on the Atrial Fibrillation registry to Follow the long-teRm Outcomes and use of aNTIcoagulants aftER Ablation (AF Frontier Ablation Registry) was conducted. Data were collected from 3,451 consecutive patients (74.1% men; age, 63.3±10.3 years) who had undergone AF ablation at any of 24 cardiovascular centers in Japan between August 2011 and July 2017. During a 20.7-month follow-up period, OAC therapy was discontinued in 1,836 (53.2%) patients; 51 patients (1.5%) suffered a stroke/transient ischemic attack (TIA), 71 (2.1%) suffered major bleeding, and 36 (1.0%) died. Patients in whom OAC therapy was discontinued were significantly younger than those in whom OACs were continued, and their CHA2DS2-VASc scores were significantly lower. The incidences of stroke/TIA, major bleeding, and death were significantly lower among these patients. Upon multivariate adjustment, stroke events were independently associated with relatively high baseline CHA2DS2-VASc scores but not with OAC status. CONCLUSIONS: Although the incidences of stroke/TIA, major bleeding, and death were relatively low among patients for whom OAC therapy was discontinued, stroke/TIA occurrence was strongly associated with a high baseline stroke risk rather than with OAC status. Thus, discontinuation of OAC therapy requires careful consideration, especially in patients with a high baseline stroke risk.

DOI： 10.1253/circj.CJ-19-0602

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1253/circj.CJ-19-0342

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00380-019-01347-8

PubMed

researchmap

記述言語：英語  

DOI： 10.1253/circj.CJ-19-0447

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

BACKGROUND: Ventricular fibrillation (VF) storm after myocardial infarction (MI) is a life-threatening condition that necessitates multiple defibrillations. Catheter ablation is a potentially effective treatment strategy for VF storm refractory to optimal medical treatment. However, its impact on patient survival has not been verified in a large population. METHODS: We conducted a multicenter, retrospective observational study involving consecutive patients who underwent catheter ablation of post-MI refractory VF storm without preceding monomorphic ventricular tachycardia. The target of ablation was the Purkinje-related ventricular extrasystoles triggering VF. The primary outcome was in-hospital and long-term mortalities. Univariate logistic regression and Cox proportional-hazards analysis were used to evaluate clinical characteristics associated with in-hospital and long-term mortalities, respectively. RESULTS: One hundred ten patients were enrolled (age, 65±11years; 92 men; left ventricular ejection fraction, 31±10%). VF storm occurred at the acute phase of MI (4.5±2.5 days after the onset of MI during the index hospitalization for MI) in 43 patients (39%), the subacute phase (>1 week) in 48 (44%), and the remote phase (>6 months) in 19 (17%). The focal triggers were found to originate from the scar border zone in 88 patients (80%). During in-hospital stay after ablation, VF storm subsided in 92 patients (84%). Overall, 30 (27%) in-hospital deaths occurred. The duration from the VF occurrence to the ablation procedure was associated with in-hospital mortality (odds ratio for each 1-day increase, 1.11 [95% CI, 1.03-1.20]; P=0.008). During follow-up after discharge from hospital, only 1 patient developed recurrent VF storm. However, 29 patients (36%) died, with a median survival time of 2.2 years (interquartile range, 1.2-5.5 years). Long-term mortality was associated with left ventricular ejection fraction <30% (hazard ratio, 2.54 [95% CI, 1.21-5.32]; P=0.014), New York Heart Association class ≥III (hazard ratio, 2.68 [95% CI, 1.16-6.19]; P=0.021), a history of atrial fibrillation (hazard ratio, 3.89 [95% CI, 1.42-10.67]; P=0.008), and chronic kidney disease (hazard ratio, 2.74 [95% CI, 1.15-6.49]; P=0.023). CONCLUSIONS: In patients with MI presenting with focally triggered VF storm, catheter ablation of culprit triggers is lifesaving and appears to be associated with short- and long-term freedom from recurrent VF storm. Mortality over the long-term follow-up is associated with the severity of underlying cardiovascular disease and comorbidities in this specific patient population.

DOI： 10.1161/CIRCULATIONAHA.118.037997

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00380-018-1278-2

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jacep.2018.11.005

PubMed

researchmap

DOI： 10.1016/j.ijcha.2018.12.012

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1253/circj.CJ-18-1131

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1161/CIRCEP.118.006969

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijcard.2018.07.135

PubMed

researchmap

DOI： 10.1136/bcr-2018-226480

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

INTRODUCTION: Protection from lethal ventricular arrhythmias leading to sudden cardiac death is one of the most important problems after myocardial infarction. Cardiac sympathetic hyperactivity is related to poor prognosis and fatal arrhythmias and can be non-invasively assessed with heart rate variability, heart rate turbulence, T-wave alternans, late potentials, and 123I-meta-iodobenzylguanide (123I-MIBG) scintigraphy. Sodium glucose cotransporter 2 (SGLT2) inhibitors potentially reduce sympathetic nervous system activity that is augmented in part due to the stimulatory effect of hyperglycemia. The EMBODY trial is designed to determine whether the suppression of cardiac sympathetic activity induced by the SGLT2 inhibitor is accompanied by protection against adverse cardiovascular outcomes. METHODS: The EMBODY trial is a prospective, multicenter, randomized, double-blind, placebo-controlled trial in patients with acute MI and type 2 diabetes in Japan. A total of 98 patients will be randomized (1:1) to receive once-daily placebo or empagliflozin, an SGLT2 inhibitor, 10 mg. The primary end point is the change from baseline to 24 weeks in heart rate variability. Secondary end points include the change from baseline for other sudden cardiac death surrogate-markers such as heart rate turbulence, T-wave alternans, late potentials, and 123I-MIBG scintigraphy imaging. Adverse effects will be evaluated throughout the trial period. PLANNED OUTCOMES: The EMBODY trial will evaluate the potential cardioprotective effect of empagliflozin and will provide additional important new data regarding its preventative effects on sudden cardiac death. TRIAL REGISTRATION: Unique Trial Number, UMIN000030158 ( https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000034442 ). FUNDING: Nippon Boehringer Ingelheim and Eli Lilly and Company.

DOI： 10.1007/s13300-018-0480-7

PubMed

researchmap

記述言語：日本語   出版者・発行元：(一社)日本内科学会  

79歳男。約5年前に皮膚そう痒と四肢浮腫が出現し、前医で好酸球性血管性浮腫が疑われた。更に同時期に腹水貯留と腸管壁浮腫を認め、各種検査を行うも特異的な所見は認めなかった。経過より好酸球増多症候群が強く疑われ、プレドニゾロン(PSL)内服の開始にて腹水は消失した。約4年でPSLは中止したが、今回、皮膚そう痒と下腿浮腫が再発した。CTで大量の心膜液貯留を認め、血液検査で末梢血好酸球増多、血清IgEとIgG4の高値を認めた。MRIでは慢性心膜炎の所見を認めたが、心膜穿刺の細胞診で好酸球や形質細胞の増加はなく、悪性所見もなかった。経過中に突然尿閉と発熱を来たし、前立腺腫大を伴わない原発性性腺機能低下症を認めた。前立腺組織診で線維化を伴う慢性炎症を認め、IgG4/IgG形質細胞比が40%以上であったことから、臨床所見と併せてIgG4関連疾患と診断した。診断時には諸症状が軽快し、ステロイド性骨粗鬆症に起因する大腿骨頸部骨折が続発したため、ステロイドによる治療は行わず、定期的に検査を行う方針とし退院とした。

researchmap

その他リンク： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2018&ichushi_jid=J01159&link_issn=&doc_id=20180719090013&doc_link_id=10.2169%2Fnaika.107.1357&url=https%3A%2F%2Fdoi.org%2F10.2169%2Fnaika.107.1357&type=J-STAGE&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00007_3.gif

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier B.V.  

Background: Early detection of cardiac involvement in sarcoidosis is difficult but essential to achieve optimal treatment. Signal-averaged electrocardiography (SAECG) can detect subtle cardiac electrical abnormalities termed late potentials (LPs) and would be useful for the early diagnosis of cardiac involvement. Objective: This study aims to investigate the prognostic significance of LP in patients with pulmonary sarcoidosis. Methods: We prospectively studied 74 patients with pulmonary sarcoidosis without overt electrocardiographic abnormalities. All participants underwent SAECG, cardiac echocardiography, and 24-hour ambulatory Holter monitoring. Serum angiotensin-converting enzyme and B-type natriuretic peptide levels were also evaluated. We followed these patients for the evaluation of incidence of cardiac events including cardiac death, arrhythmias, and heart failure requiring hospital admission. Results: Of the studied population, 29 patients (39.2%) had detectable LP. During a mean follow-up period of 9.8 years, 8 patients with LPs had cardiovascular events, including development of complete atrioventricular block (n = 4), ventricular tachycardia (n = 2), and heart failure (n = 2). Meanwhile, only 1 of 45 patients without LP developed cardiac event (heart failure). Multivariate analyses revealed that LPs were associated with an increased risk of developing cardiac events (hazard ratio 9.66
95% confidence interval 1.20–78.01
P =.033) whereas age, sex, serum angiotensin-converting enzyme and B-type natriuretic peptide levels, number of premature ventricular contractions on 24-hour Holter monitoring, and echocardiographic parameters were not associated with subsequent cardiac events. Conclusion: SAECG might possibly be useful for the early detection of cardiac sarcoidosis and, if independently validated, could eventually be considered as a screening test for further risk stratification.

DOI： 10.1016/j.hrthm.2018.03.013

Scopus

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japanese Circulation Society  

Prevention of sudden cardiac death (SCD) has become an important issue in today's cardiovascular field, together with various developments in secondary prevention of basic cardiac diseases. The importance of the implantable cardioverter defibrillator (ICD) is now widely accepted because it has exhibited significant improvement in patients' prognoses in ischemic and non-ischemic cardiovascular diseases. However, there is an unignorable gap between the ICD indication in the guidelines and real-world high-risk patients for SCD, especially in the acute recovery phase of cardiac injury. Although various studies have demonstrated a clinical benefit of defibrillation devices, the studies of immediate ICD use in the acute recovery phase have failed to exhibit a benefit in patients from the point of the view of a decrease in total deaths. To bridge this gap, the wearable cardioverter defibrillator (WCD) provides a safer observation period in the acute phase and eliminates inappropriate overuse of ICD in the subacute phase. Here, we discuss the usefulness of the WCD and current understanding of its indications based on various clinical data. In conclusion, WCD is a feasible bridge to therapy and/or safe observation for patients at high risk of SCD, especially in the acute recovery phase of cardiac diseases.

DOI： 10.1253/circj.CJ-17-1336

Scopus

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Turkish Society of Cardiology  

DOI： 10.14744/AnatolJCardiol.2017.25931

Scopus

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

Atrial fibrillation (AF) itself creates structural and electrophysiological changes such as atrial enlargement, shortening of refractory period and decrease in conduction velocity, called "atrial remodeling", promoting its persistence. Although the remodeling process is considered to be reversible, it has not been elucidated in detail. The aim of this study was to assess the feasibility of P wave dispersion in the assessment of reverse atrial remodeling following catheter ablation of AF. Consecutive 126 patients (88 males, age 63.0 +/- 10.4 years) who underwent catheter ablation for paroxysmal AF were investigated. P wave dispersion was calculated from the 12 lead ECG before, 1 day, 1 month, 3 months and 6 months after the procedure. Left atrial diameter (LAD), left atrial volume index (LAVI), left ventricular ejection fraction (LVEF), transmitral flow velocity waveform (E/A), and tissue Doppler (E/e') on echocardiography, plasma B-type natriuretic peptide (BNP) concentrations, serum creatinine, and estimated glomerular filtration rate (eGFR) were also measured. Of all patients, 103 subjects remained free of AF for 1 year follow-up. In these patients, P wave dispersion was not changed 1 day and 1 month after the procedure. However, it was significantly decreased at 3 and 6 months (50.1 +/- 14.8 to 45.4 +/- 14.4 ms, p &lt; 0.05, 45.2 +/- 9.9 ms, p &lt; 0.05, respectively). Plasma BNP concentrations, LAD and LAVI were decreased (81.1 +/- 103.8 to 44.8 +/- 38.3 pg/mL, p &lt; 0.05, 38.2 +/- 5.7 to 35.9 +/- 5.6 mm, p &lt; 0.05, 33.3 +/- 14.2 to 29.3 +/- 12.3 mL/m(2), p &lt; 0.05) at 6 months after the procedure. There were no significant changes in LVEF, E/A, E/e', serum creatinine, and eGFR during the follow up period. P wave dispersion was decreased at 3 and 6 months after catheter ablation in patients without recurrence of AF. P wave dispersion is useful for assessment of reverse remodeling after catheter ablation of AF.

DOI： 10.1007/s00380-017-1008-1

Web of Science

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL  

Introduction: The concept of a 3-month blanking period is widely accepted after the first radiofrequency catheter ablation (RFCA) session for atrial fibrillation (AF). We sought to investigate whether this phenomenon was also observed after a 2nd session, and which factors were related to it.
Methods and Results: We conducted a prospective observational study including all AF patients who underwent RFCA since 2010. The patients who underwent a second RFCA were followed without any antiarrhythmic drugs. Their clinical background, laboratory data, echocardiographic parameters, ablation procedures, and arrhythmia recurrences were analyzed. Recurrences were classified into early period recurrences (EPRs) and late period recurrences (LPRs) recorded within and after the first 3 months postablation, respectively. Among 925 patients who underwent an initial AF ablation, 2nd sessions were performed in 250 patients, and EPRs and LPRs occurred in 53 (21.2%) and 54 (21.6%) patients, respectively. Although EPRs were an independent predictor of LPRs (hazard ratio [HR], 8.01; 95% confidence interval [CI] 4.03-15.93, P &lt;0.001), 20 of the patients with EPRs (37.7%) did not experience LPRs, supporting the concept of a blanking period. Among 53 patients with EPRs, the E/ E' ratio on echocardiography (HR, 1.156; 95% CI 1.00-1.33, P = 0.04) was an independent predictor of LPRs, while other parameters including the maximum serum C-reactive protein level after the session and the ablation procedure details were not.
Conclusion: A 3-month blanking period was also applicable after the 2nd AF ablation session. This phenomenon was related to a lower left atrial pressure demonstrated by the E/ E' ratio.

DOI： 10.1111/jce.13129

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER IRELAND LTD  

Background: Pacing from the right ventricular apex (RVA) is associated with cardiac dysfunction and shows electrophysiological features similar to left bundle branch block in which left ventricular (LV) mechanical dyssynchrony impairs septal coronary artery perfusion.
Methods: A total of 62 non-ischemic patients with an implanted pacemaker at the RVA with a pacing rate of &gt;95% were studied. LV septal coronary perfusion as indicated by the LV septal perfusion index was measured by electrocardiography (ECG)-gated single-photon emission computed tomography for all patients at baseline and for patients who were upgraded to CRT at 6 months after CRT. Relationships among LV septal perfusion index, QRS duration, and LV ejection fraction were analyzed.
Results: Among the patients with permanent RVA pacing, 28 of 62 (45%) had impaired septal perfusion (i.e., septal perfusion index &lt;0.9). The LV septal perfusion index was significantly correlated with both QRS duration (r=-0.763, p &lt; 0.001) and LV ejection fraction (r = 0.462, p = 0.001). Eleven patients were upgraded to CRT. CRT significantly improved the LV septal perfusion index from 0.63 (SD = 0.13) to 0.89 (SD = 0.19) (p &lt; 0.001) and cardiac function: LV end-systolic volume from 102.3 mL (SD = 70.0) to 179.7 mL (SD = 118.4) (p = 0.002) and LV ejection fraction from 22.5 (SD = 8.9%) to 38.4% (SD = 13.9%) (p = 0.001).
Conclusions: Nearly half of the non-ischemic patients with permanent RVA pacing presenting with prolonged QRS duration and LV dysfunction developed LV septal hypoperfusion. Both septal perfusion and LV function improved in patients who were upgraded to CRT. (C) 2016 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.ijcard.2016.09.031

Web of Science

PubMed

researchmap

記述言語：英語   出版者・発行元：JAPANESE CIRCULATION SOC  

DOI： 10.1253/circj.CJ-16-0992

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

Atrial fibrillation (AF) is one of the major risk factor for ischemic stroke, and oral anticoagulation is generally indicated for prevention of stroke. However, the utility of oral anticoagulation for AF in dialysis patients remains controversial. In this single-center, retrospective, observational study, data from 1120 patients on maintenance hemodialysis were analyzed. Baseline medical data were collected from dialysis records including age, gender, the cause of end-stage renal disease, dialysis vintage, and comorbidities. We evaluated outcomes including stroke, major hemorrhage, and death. A total of 106 (11.4 %) patients had AF. After exclusion criteria were applied, 84 patients had analyzable data. Warfarin was prescribed in 30 (35.7 %) of these patients. The remaining 54 patients were classified as the non-warfarin group. CHADS2 score was not significantly different between the warfarin and non-warfarin group. During the mean 47 months of follow up, 7 strokes occurred. However, warfarin use was not associated with the risk for stroke [hazard ratio (HR) 1.07; 95 % confidence interval (CI) 0.20-5.74]. Kaplan-Meier analysis showed no statistically significant difference in the overall survival, stroke-free survival or bleeding-free survival between the warfarin and non-warfarin group. AF is common in Japanese dialysis patients. Despite a certain prevalence of oral anticoagulation, the present study demonstrated neither beneficial nor detrimental effects. A large randomized controlled trial should be considered.

DOI： 10.1007/s00380-015-0777-7

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE INC  

B ackground: Hypertension is one of the independent risk factors for atrial fibrillation (AF). Pulmonary veins (PVs) play an important role as the substrate for AF and triggers of AF. The purpose of this study was to determine the structural remodelling of the PVs and its effect on promoting AF in hypertensive (HT) rat hearts.
Methods: Eighteen-week-old Dahl salt-sensitive HT rats and their controls were used for histological and immunohistological analyses, and electrophysiological studies were performed in Langendorff perfused hearts.
Results: Masson-trichrome staining revealed that hypertension significantly increased the fibrosis in the PVs, particularly in subendocardial and perivascular areas, compared with that in control rats, however, at this early stage of hypertension, left atrial fibrosis was not prominent. In the HT rat hearts with PVs, electrical stimulation significantly increased the number of repetitive atrial firing and atrial tachycardia inducibility, which significantly diminished after the excision of the PVs. An immunofluorescent analysis revealed that HT rats had PV specific endocardial smooth muscle actin (aSMA)-positive cells with remarkable proliferation of platelet-derived growth factor (PDGF)-C and vascular endothelial growth factor (VEGF), which was lacking in the left atrial structures of the control and the HT rats. Pretreatment with imatinib, a PDGF receptor activity blocker, in HT rats reduced the aSMA-positive cell proliferation and fibrosis in the PVs and also induced a significant reduction in VEGF expression. Also, the drug pretreatment effectively prevented repetitive atrial firing promotion without affecting the blood pressure.
Conclusions: PV preferential fibrosis might play an important role in the arrhythmogenic substrate of AF in HT rat hearts.

DOI： 10.1016/j.cjca.2015.09.006

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：INT HEART JOURNAL ASSOC  

Chronic inflammation is known to occur in diabetes mellitus (DM) and contributes to atrial fibrosis, possible substrates for atrial fibrillation. We tested the hypothesis that dipeptidyl peptidase (DPP)-4 inhibitors prevent the formation of atrial fibrosis through their anti-inflammatory activity, beyond the effects of controlling blood glucose.
DM models obtained by administration of streptozotocin (STZ) were divided into 3 groups: with PKF275-055, a DPP-4 inhibitor in group D, glibenclamide in group SU, and no additional drug in group P. At 8 weeks after STZ administration, the heart was subjected to Masson trichrome staining and immunohistochemistry with anti-ED2, ED3, and smooth muscle actin antibody.
The % area of fibrosis in atria of group P accounted for 14.7% +/- 4.1%, showing a significant increase in fibrosis when compared with the control group. In group SU, the % area accounted for 7.9% +/- 2.9%, indicating significant deceased fibrosis by sulfonylurea. Meanwhile, we could not find significant differences in group D when compared to group P or group SU. While ED3-positive cells increased in group P (1.12% +/- 0.24%), they were significantly decreased in groups D and SU (0.41% +/- 0.22% and 0.55% +/- 0.29%, respectively). Between group D and SU, however, there were no significant differences in the amount of cells positive to ED2, ED3, and smooth muscle actin antibodies.
In STZ-induced DM rats, administration of sulfonylurea and DPP-4 inhibitors inhibited inflammation and fibrosis of the atria. However, no significant differences were observed between the 2 antidiabetic drugs.

DOI： 10.1536/ihj.15-266

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE INC  

BACKGROUND Atrial tachycardia (AT) may develop after biatrial surgical ablation of atrial fibrillation. However, the mechanism has not been determined in detail.
OBJECTIVE We aimed to determine the mechanism and treatment of postoperative AT following biatrial surgical ablation in relation to the design and durability of the surgical lesion sets.
METHODS An electrophysiologic study and radiofrequency ablation were performed in 34 consecutive patients (23 male, mean age of 63 +/- 9.4 years) who were referred for AT that developed late after biatrial surgical ablation.
RESULTS The mechanism of a total of 53 ATs was macroreentry in 30, a focal mechanism in 20, and localized reentry in 1, and could not be determined in 2. The cause of the macroreentrant AT was residual conduction across a surgical lesion, most of which was located at the annular end of the mitral (n = 18) or tricuspid isthmus incision (n = 7), where cryoablation was applied during the surgery. We did not find any gaps across the cut-and-sew lesions. Radiofrequency (RF) applications to the gap, or an alternative site to transect the circuit, or the earliest activation site of the focus was effective for 48 ATs (91%). After a total of 1.3 +/- 0.6 RF sessions, 27 patients (79%) were free of AT (n = 2) or AF (n = 5) during a follow-up period of 50 49 months.
CONCLUSIONS Macroreentry due to a gap in a surgical lesion and focal AT were the major mechanisms of AT in patients after biatrial surgical ablation. Radiofrequency ablation of those ATs is feasible.

DOI： 10.1016/j.hrthm.2015.12.033

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MEDICAL ASSOC NIPPON MEDICAL SCH  

Background: Urgent catheter ablation is often required for various tachyarrhythmias; however, its efficacy and safety in elderly patients have not been fully elucidated.
Methods: This study included consecutive octogenarians who underwent urgent radiofrequency catheter ablation (RFCA) for various serious tachyarrhythmias (urgent group, n=28) that were life threatening, hemodynamically deleterious, or provoking ischemia, and consecutive octogenarians who underwent elective RFCA (control group, n=36). The rate of a successful RFCA, complications, later arrhythmia recurrences, and mortality were compared between the groups.
Results: There was no significant difference in the breakdown of the targeted arrhythmias between the groups, and common-type atrial flutter was most often targeted in both the urgent group (57%) and the elective group (56%). Compared with the control group patients, the patients of the urgent group were older (84 +/- 3 vs. 82 +/- 2 years P=0.001), with a higher frequency of baseline heart disease (68% vs. 17%, P &lt;0.001) and lower left ventricular ejection fraction (45% +/- 15% vs. 68% +/- 10%, P&lt;0.001). The rates of acute success (100% vs. 100%, P=1.00) and later arrhythmia recurrences (4% vs. 14%, P=0.22) were comparable between the groups. Two patients in the urgent group and 2 in the elective group had procedure-related nonlethal complications (7% vs. 6%, P=1.00): groin hematoma in 2, pressure ulcer in 1, and CO2 narcosis in 1. There were no in-hospital deaths, and mortality during follow-up did not differ between the urgent and elective groups (6.0% vs. 3.9% per year, log-rank P=0.38).
Conclusion: Even in octogenarian patients, urgent catheter ablation for serious tachyarrhythmias can be safely performed with a high success rate and acceptable prognosis.

DOI： 10.1272/jnms.83.62

Web of Science

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOC INTERNAL MEDICINE  

A 46-year-old man was admitted to our hospital for near syncope and palpitations. An electrocardiogram showed a common type of atrial flutter (AFL) with 1: 1 atrioventricular conduction. Transthoracic echocardiography revealed a massive right atrial (RA) thrombus with a huge RA and right ventricle. The patient was diagnosed with arrhythmogenic right ventricular cardiomyopathy. It was difficult to control the heart rate with beta-blockers during AFL, which resulted in the deterioration of right-sided heart failure. The effect of anticoagulation therapy for the RA thrombus was also limited. Restoration to sinus rhythm by catheter ablation effectively improved the right-sided heart failure, and the massive RA thrombus eventually disappeared.

DOI： 10.2169/internalmedicine.55.5520

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE CIRCULATION SOC  

Background: Few reports are available on the characteristics of electrical storms of ventricular tachycardia (VT storm) refractory to intravenous (IV) amiodarone.
Methods and Results: IV-amiodarone was administered to 60 patients with ventricular tachyarrhythmia between 2007 and 2012. VT storms, defined as 3 or more episodes of VT within 24 h, occurred in 30 patients (68 +/- 12 years, 7 female), with 12 having ischemic and 18 non-ischemic heart disease. We compared the clinical and electrocardiographic characteristics of the patients with VT storms suppressed by IV-amiodarone (Effective group) to those of patients not affected by the treatment (Refractory group). IV-amiodarone could not control recurrence of VT in 9 patients (30%). The Refractory group comprised 5 patients with acute myocardial infarctions. Although there was no difference in the VT cycle length, the QRS duration of both the VT and premature ventricular contractions (PVCs) followed by VT was narrower in the Refractory group than in the Effective group (140 +/- 30 vs. 178 +/- 25 ms, P&lt;0.01; 121 +/- 14 vs. 179 +/- 22 ms, P&lt;0.01). In the Refractory group, additional administration of IV-mexiletine and/or Purkinje potential-guided catheter ablation was effective.
Conclusions: IV-amiodarone-refractory VT exhibited a relatively narrow QRS tachycardia. The narrow triggering PVCs, suggesting a Purkinje fiber origin, may be treated by additional IV-mexiletine and endocardial catheter ablation.

DOI： 10.1253/circj.CJ-15-0213

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MEDICAL ASSOC NIPPON MEDICAL SCH  

Background: Current standard 12-lead electrocardiogram (ECG) criteria for diagnosing pulmonary hypertension (PH) have a low sensitivity. Although the right-sided chest ECG (V3R-V5R) increases the diagnostic accuracy, these additional leads are not routinely recorded. The aim of the present study was to assess the usefulness of the synthesized right-sided chest ECG (Syn-ECG), generated from 12-lead ECG information, in the detection and evaluation of PH.
Patients and Methods: The Syn-ECG waveforms in 30 patients with PH, defined as an estimated pulmonary arterial systolic pressure (PASP) &gt;35 mmHg, were compared to those in 30 age- and gender-matched normal subjects.
Results: The R wave amplitude and R/S ratio in the Syn-ECGs were significantly (P&lt;0.01) greater in patients with PH than in the controls. The R wave amplitude in the Syn-ECGs exhibited a significant and better correlation (correlation coefficient 0.513-0.596, P&lt;0.001) with the PASP than lead V1 (correlation coefficient 0.375, P=0.02). A receiver-operating characteristic curve analysis showed that the R wave amplitude (AUC 0.802, P&lt;0.001) and R/S ratio (AUC 0.823, P&lt;0.001) in the synthesized V5R was a good predictor of PH. New criteria, including 1) an R in V5R&gt;0.12 mV, and 2) R/S ratio in V5R&gt;0.42, had an improved sensitivity (0.63 and 0.73, respectively) and comparable specificity (0.93 and 0.87, respectively) to the conventional criteria (sensitivity 0.10-0.43, specificity 0.90-1.00).
Conclusion: The diagnostic criteria derived from the Syn-ECG provided better diagnostic accuracy than the known conventional criteria from the standard 12-lead ECG. This technique described in the present study may be useful for diagnosing and evaluating PH.

DOI： 10.1272/jnms.82.136

Web of Science

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE INC  

BACKGROUND Obstructive sleep apnea (OSA) importantly contributes to the occurrence of atrial fibrillation (AF) in humans, but the mechanisms are poorly understood. Experimental research has provided insights into AF promotion by acute OSA episodes. However, patients with OSA usually have frequent nocturnal episodes for some time before manifesting AF.
OBJECTIVES The goal of this study was to test the hypothesis that repetitive OSA causes cardiac remodeling that predisposes to AF.
METHODS We mimicked OSA by using a mechanical ventilator and closing the airway at end-expiration with a 3-way stopcock (OSA rats). Matched control groups included rats with the ventilator stopped but airway left open (open airway rats) and continuously ventilated rats (sham rats). OSA rats were exposed to 20 consecutive 2-min cycles of 40 s of apnea/80 s of ventilation per day, 5 days per week for 4 weeks.
RESULTS OSA significantly increased the duration of AF from (median [interquartile range]) 2.6 s [1.9 s to 8.9 s] (shams) and 16 s [1.8 s to 93 s] (open airway) to 49s [34 s to 444 s]. AF inducibility increased to 56% (9 of 16) of OSA rats; this is up from 15% (2 of 13) and 13% (2 of 15) in open airway and sham rats, respectively (p &lt; 0.05). OSA rats exhibited substantial atrial conduction slowing on optical mapping, along with connexin-43 down-regulation on both quantitative immunofluorescence (expression reduced by 58% vs sham rats) and Western blot (reduced by 38%), as well as increased atrial fibrous tissue content (by 71%). OSA also caused left ventricular hypertrophy, dilation, and diastolic dysfunction and enhanced AF inducibility during superimposed acute OSA episodes to 82.4% of rats.
CONCLUSIONS Chronically repeated OSA episodes cause AF-promoting cardiac remodeling, with conduction abnormalities related to connexin dysregulation and fibrosis playing a prominent role. This novel animal model provides mechanistic insights into an important clinical problem and may be useful for further exploration of underlying mechanisms and therapeutic approaches. (C) 2014 by the American College of Cardiology Foundation.

DOI： 10.1016/j.jacc.2014.05.077

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：OXFORD UNIV PRESS  

Atrial tachyarrhythmias (AT) commonly recur within the first 3 months after radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF), and the influence of antiarrhythmic drugs (AADs) on the recurrences has not been fully elucidated. We sought to evaluate the efficacy of a 3-month lower-dose flecainide regime on early and late recurrences of ATs.
We randomly assigned 126 patients, who underwent RFCA for AF, to the flecainide group (150 or 100 mg/day according to their body weight) or to the control group receiving no AADs. The primary endpoint was any AT lasting for a parts per thousand yen30 s during the first 3 months and the secondary endpoint was a composite of ATs lasting for a parts per thousand yen24 h or requiring cardioversion or hospitalization during the same period. All AADs were stopped after the first 3 months and the late arrhythmia recurrences were also evaluated. The primary endpoint rates were 37 and 41% in the flecainide (143 +/- 19 mg/day) and control groups, respectively (log-rank P = 0.76), and those of the secondary endpoint were 10 and 14%, respectively (log-rank P = 0.45). The estimated rates of maintaining sinus rhythm at 12 months after the first 3 months were 78 and 72%, in the flecainide and control groups, respectively (log-rank P = 0.68), and the rates were 51 and 90% in those with and without the primary endpoint, respectively (log-rank P &lt; 0.001).
The 3-month lower-dose flecainide therapy after AF ablation did not reduce the early and late arrhythmia recurrences. The clinically significant ATs were also not prevented.

DOI： 10.1093/europace/euu041

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

Purpose Catheter ablation of atrial fibrillation (AF) in patients with hypertrophic cardiomyopathy (HCM) is still challenging, and it is unclear whether the difficulty is caused by the hypertrophy of left atrial (LA) myocardial wall thickness. The objective of the study was to compare the LA wall thickness and AF ablation outcomes between patients with HCM and those without structural heart disease.
Methods The present study enrolled 17 consecutive HCM patients (63+/-12 years) with drug-refractory AF and 34 control patients without any detectable heart disease, whose age, gender, type of AF, and LA dimension were matched to the HCM patients. The myocardial wall thickness of 11 distinct LA locations, measured using 64-slice computed tomography images, and AF ablation outcomes were compared between the two groups.
Results The LA wall thickness did not differ at 9 of the 11 locations and was significantly thinner in the HCM patients than in the control patients at the mid-posterior wall (1.44+/-0.17 vs. 1.58+/-0.22, p=0.04) and infero-posterior wall (1.62+/-0.16 vs. 1.74+/-0.18, p=0.03). Although antiarrhythmic drugs were used more frequently in the HCM patients (p=0.008), the rate of maintaining sinus rhythm during the follow-up did not differ between the HCM and control patients (53 vs. 56 % after the initial ablation [log-rank p=0.78] and 82 and 88 % after the repeat procedure [log-rank p=0.35]).
Conclusions The LA wall in the HCM patients with AF was not thicker than that of the matched patients without structural heart disease. Catheter ablation of AF showed favorable outcomes in both patient groups.

DOI： 10.1007/s10840-014-9894-y

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：MEDICAL ASSOC NIPPON MEDICAL SCH  

Background: The periesophageal vagus nerve plexus controls the kinetics of the stomach, digestive tract, and gallbladder, and catheter ablation of atrial fibrillation (AF) can cause vagus nerve injury (VNI). We sought to clarify the incidence, clinical course, and anatomical factors related to periesophageal VNI.
Methods: The present study included 257 consecutive patients with AF (mean age, 62 11 years) who underwent catheter-based pulmonary vein isolation. With 64-slice computed tomographic images, the left atrium (LA)-esophageal contact length, LA diameter, and distances between each mediastinal structure were compared between patients with VNI and those without VNI.
Results: VNI occurred in 5 patients (1.9%), gastric hypomotility in 3 patients, and acalculous cholecystitis in 2 patients, within 3 days after ablation, and all patients recovered completely within 2 weeks. Compared with patients without VNI, those with VNI more frequently underwent ablation at the mitral isthmus (p=0.03) and inside the coronary sinus (p=0.03). On computed tomographic images, the esophagus was closer to the aorta than to the spine in 67% of patients and was defined as an aorta-sided esophagus. In patients with VNI, the distance from the LA to the spine or the descending aorta (in patients with an aorta-sided esophagus) was shorter (p=0.03), and the transverse LA-esophageal contact length was longer (p=0.01).
Conclusion: Acalculous cholecystitis, as well as gastric hypomotility, can develop as a result of periesophageal VNI in patients undergoing AF ablation. The anatomical relationships among the LA, esophagus, spine, and descending aorta may influence the occurrence of VNI.

DOI： 10.1272/jnms.81.248

Web of Science

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本不整脈心電学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本不整脈心電学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本不整脈心電学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本不整脈心電学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL  

Effects of T-Type Calcium Channel Blockade on AF
Background
The T-type Ca2+ channel (I-CaT) blocker mibefradil prevents AF-promoting remodeling occurring with atrial tachycardia, an action that has been attributed to I-CaT inhibition. However, mibefradil has other effects, including ability to inhibit L-type Ca2+ channels, Na+ channels and cytochromes. Thus, the relationship between I-CaT inhibition and remodeling protection in AF is still unknown.
Objective
To assess the effects of a novel highly selective Cav3 (I-CaT) blocker, AZ9112, on atrial remodeling induced by 1-week atrial tachypacing (AT-P) in dogs.
Methods
Mongrel dogs were subjected to AT-P at 400 bpm for 7days, with atrioventricular-node ablation and right-ventricular demand pacing (80 bpm) to control ventricular rate. Four groups of dogs were studied in investigator-blinded fashion: (1) a sham group, instrumented but without tachypacing or drug therapy (n= 5); (2) a placebo group, tachypaced but receiving placebo (n= 6); (3) a positive control tachypacing group receiving mibefradil (n= 6); and (4) a test drug group, subjected to tachypacing during oral treatment with AZ9112 (n= 8).
Results
One-week AT-P decreased atrial effective refractory period (ERP) at 6 of 8 sites and diminished rate-dependent atrial ERP abbreviation. Mibefradil eliminated AT-P-induced ERP-abbreviation at 4 of these 6 sites, while AZ9112 failed to affect ERP at any. Neither drug significantly affected AF vulnerability or AF duration.
Conclusions
I-CaT blockade with the highly selective compound AZ9112 failed to prevent rate-related atrial remodeling. Thus, prevention of atrial electrophysiological remodeling by mibefradil cannot be attributed exclusively to I-CaT blockade. These results indicate that I-CaT inhibition is not likely to be a useful approach for AF therapy.

DOI： 10.1111/jce.12346

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE INC  

BACKGROUND Left bundle branch block (LBBB) causes intraventricular conductional delay, which results in left ventricle (LV) mechanical dyssynchrony. In the absence of coronary artery disease, patients with LBBB often have diminished accumulation of technetium-99m compounds at the myocardial septal area in electrocardiogram-gated single-photon emission computed tomography.
OBJECTIVE To investigate whether cardiac resynchronization therapy (CRT) could improve septal myocardial perfusion, Leading to favorable reverse remodeling.
METHODS The study included all 26 patients with nonischemic cardiomyopathy eligible for CRT, who presented with LBBB, New York Heart Association class II-IV heart failure, and LV ejection fraction &lt;= 35%. Single-photon emission computed tomography was performed at baseline and 6 months after CRT. Perfusion counts were measured at the ventricular septum and LV Lateral free wall. Left ventricular end-systolic volume (LVESV) was measured by echocardiography to evaluate LV reverse remodeling by CRT.
RESULTS At baseline, a perfusion defect at the LV septal myocardial area was confirmed in 19 of 26 (73%) patients. In these patients, septal perfusion significantly increased 6 months after CRT (56.1% +/- 22.8% vs 82.9% +/- 21.2%; P &lt; .001). LVESV reduction and improved septal perfusion index were positively correlated (r = .561; P = .012), whereas no correlation was found between LVESV reduction and the difference of QRS duration before and 6 months after CRT (r = .218; P = .371). The improvement in LV septal perfusion was associated with LV reverse remodeling.
CONCLUSIONS CRT could restore LV septal myocardial perfusion and ameliorate ventricular reverse remodeling in most patients with nonischemic cardiomyopathy and LBBB.

DOI： 10.1016/j.hrthm.2014.02.014

Web of Science

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：OXFORD UNIV PRESS  

Aims Ventricular tachycardia (VT) and ventricular fibrillation (VF) are not uncommon in patients hospitalized with acute heart failure (AHF). We sought to evaluate the efficacy of urgent radiofrequency catheter ablation (RFCA) for recurrent VT/VF during AHF decompensations.
Methods and results The present study retrospectively analysed the data of 15 consecutive patients (69 +/- 9 years, ischaemic heart disease in 10), who underwent urgent RFCA for frequent drug-refractory VT/VF episodes during an AHF decompensation with pulmonary congestion. The target arrhythmias were clinically documented monomorphic VTs in 10 patients, frequent premature ventricular contractions (PVCs) triggering VF in 4, and both in 1. The mean left ventricular ejection fraction was 26 +/- 8%. The maximum number of arrhythmia episodes over 24 h was 9.1 +/- 11.7. All RFCA sessions were completed without any major complications except for a temporary deterioration of pulmonary congestion in three patients (20%). Elimination and non-inducibility of the target arrhythmias were achieved in 13 patients (87%). Successful ablation site electrograms showed Purkinje potentials for all 5 PVCs triggering VF and 4 of 14 clinically documented monomorphic VTs (29%). Five patients (33%) underwent second sessions 10 +/- 4 days after the first session for acute recurrences. Sustained VT/VF was completely suppressed during admission in 12 patients (80%), and the AHF ameliorated in 13 patients (93%). Twelve patients (80%) were discharged alive.
Conclusion Urgent RFCA for drug-resistant sustained ventricular tachyarrhythmias during AHF decompensations would be an appropriate therapeutic option. Purkinje fibres can be ablation targets not only in those with PVCs triggering VF, but also in those with monomorphic VT.

DOI： 10.1093/europace/eut207

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER IRELAND LTD  

Background: Atrioventricular (AV) block is one of the main clinical manifestations in patients with cardiac sarcoidosis (CS). Although steroid therapy is considered to be effective for AV block, the efficacy has not been demonstrated in detail.
Methods and results: Fifteen CS patients presenting with advanced or complete AV block were retrospectively investigated. All patients were treated with 30 mg/day of prednisone after device implantation, which was tapered to a maintenance dosage of 5-10 mg/day. During a mean follow-up of 7.1 years, AV block resolved to normal conduction or first-degree AV block in 7 patients (recovery group). The improvement was driven within the first week of steroid therapy in 4 patients, while 3 patients showed late recovery of AV conduction. The remaining 8 patients were classified as the non-recovery group. The recovery group showed a higher left ventricular ejection fraction (69.4 8.9% versus 44.1 19.3%, p = 0.029) and higher prevalence of advanced AV block (87.5% versus 28.6%, p = 0.040) compared with those of the non-recovery group. In patients with the recovery group, there was no late recurrence of AV block during the follow-up period.
Conclusions: Early initiation of steroid therapy may be effective for AV block, and steroid therapy before device implantation is a possible therapeutic strategy for some selected patients. (C) 2013 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jjcc.2013.07.007

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

AimsThe antiarrhythmic effect of triple-site biventricular stimulation (Tri-V) is poorly understood. This study aims to evaluate the effect of cardiac resynchronization therapy (CRT) on ventricular arrhythmia (VA) with Tri-V using a single right ventricular (RV) and double left ventricular (LV) lead.Methods and resultsOver a period of 3.5 years, 58 consecutive patients with New York Heart Association class II-IV heart failure, an LV ejection fraction of ≤0.35, and a QRS interval of ≥120 ms were enrolled. Acute haemodynamic responses to dual-site biventricular stimulation (Bi-V) and Tri-V were evaluated by assigning patients to a Bi-V or Tri-V group. Electrocardiogram parameters [QT interval, JT interval, and transmural dispersion of repolarization (TDR)] were measured over time after CRT. Spontaneous VA detected by telemetry was reviewed and confirmed. During a mean follow-up of 481 days after implantation, VA occurred in 2 of 22 patients in the Tri-V group and 14 of 36 patients in Bi-V group. Triple-site biventricular stimulation was thus associated with a decreased VA risk (P = 0.044). Multivariate Cox analysis showed that Tri-V pacing prevented arrhythmic events as compared with Bi-V pacing (hazard ratio, 0.13
95% confidence interval, 0.029-0.610
P = 0.009). Ventricular repolarization indices at 6 months were significantly shortened in Tri-V compared with Bi-V (QTc, -23.6 vs. -14.1%, P = 0.008
JTc, -21.4 vs. -7.7%, P = 0.005
TDRc, -39.9 vs. -17.0%, P &lt
0.001).ConclusionCompared with Bi-V, Tri-V reduced VA during long-term follow-up. Improvements in repolarization parameters may result in antiarrhythmic effects. © 2013 Published on behalf of the European Society of Cardiology. All rights reserved.

DOI： 10.1093/europace/eut134

Scopus

PubMed

researchmap

DOI： 10.1016/j.jacc.2013.01.091

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

BACKGROUND: Congestive heart failure (CHF) causes atrial fibrotic remodeling, a substrate for atrial fibrillation (AF) maintenance. MicroRNA29 (miR29) targets extracellular matrix proteins. In the present study, we examined miR29b changes in patients with AF and/or CHF and in a CHF-related AF animal model and assessed its potential role in controlling atrial fibrous tissue production. METHODS AND RESULTS: Control dogs were compared with dogs subjected to ventricular tachypacing for 24 hours, 1 week, or 2 weeks to induce CHF. Atrial miR29b expression decreased within 24 hours in both whole atrial tissue and atrial fibroblasts (-87% and -92% versus control, respectively; p<0.001 for both) and remained decreased throughout the time course. Expression of miR29b extracellular matrix target genes collagen-1A1 (COL1A1), collagen-3A1 (COL3A1), and fibrillin increased significantly in CHF fibroblasts. Lentivirus-mediated miR29b knockdown in canine atrial fibroblasts (-68%; p<0.01) enhanced COL1A1, COL3A1, and fibrillin mRNA expression by 28% (p<0.01), 19% (p<0.05), and 20% (p<0.05), respectively, versus empty virus-infected fibroblasts and increased COL1A1 protein expression by 90% (p<0.05). In contrast, 3-fold overexpression of miR29b decreased COL1A1, COL3A1, and fibrillin mRNA by 65%, 62%, and 61% (all p<0.001), respectively, versus scrambled control and decreased COL1A1 protein by 60% (p<0.05). MiR29b plasma levels were decreased in patients with CHF or AF (by 53% and 54%, respectively; both p<0.001) and were further decreased in patients with both AF and CHF (by 84%; p<0.001). MiR29b expression was also reduced in the atria of chronic AF patients (by 54% versus sinus rhythm; p<0.05). Adenoassociated viral-mediated knockdown of miR29b in mice significantly increased atrial COL1A1 mRNA expression and cardiac tissue collagen content. CONCLUSIONS: MiR29 likely plays a role in atrial fibrotic remodeling and may have value as a biomarker and/or therapeutic target.

DOI： 10.1161/CIRCULATIONAHA.112.001207

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Background-The most important complication of atrial fibrillation (AF) is thromboembolic stroke. Although AF-related remodeling is considered important in atrial thrombogenesis, its role never has been directly tested. This study assessed effects of AF-related remodeling on the atrial thrombogenic milieu by using radiofrequency ablation (RFA) to create a quantifiable prothrombotic nidus.
Methods and Results-We studied normal control dogs (control, n=16) and 3 canine AF-models: (1) atrial tachycardia remodeling (ATR; n=16) induced by atrial tachypacing (400 bpm for 1 week, with atrioventricular block and ventricular pacing at 80 bpm); (2) congestive heart failure (CHF; n=14) attributable to ventricular tachypacing (240 bpm for 2 weeks); and (3) chronic AF (CAF; n=8) induced by atrial tachypacing (35 +/- 3 days) without atrioventricular block. CAF dogs had AF for 13 +/- 1 days until euthanization. After remodeling was established, RFA lesions were created in both atria. Half the ATR and CHF dogs were subjected to atrial tachypacing during 7-day post-RFA follow-up. Electrophysiological and echocardiographic studies were performed before RFA and 7 days after RFA, and then hearts were removed and atrial thrombi were quantified by histomorphometry. Burst-pacing-induced AF duration was significantly greater in ATR, CHF, and CAF groups versus control group. The atrial effective refractory period shortened in ATR and CAF groups. Left atrial diameter was significantly larger with CHF, but not with ATR. Neither total thrombus volume nor thrombus volume per lesion differed significantly among groups.
Conclusions-None of the AF substrates tested, including sustained atrial tachycardia/AF itself, enhanced post-RFA atrial thrombus formation. Indices of electrical and structural remodeling did not predict post-RFA thrombogenic potential. Contrary to widely held but previously untested notions, we were unable to demonstrate prothrombotic effects of AF-related remodeling. (Circ Arrhythm Electrophysiol. 2012;5:1168-1175.)

DOI： 10.1161/CIRCEP.112.974410

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE INC  

BACKGROUND Obesity and obstructive sleep apnea (OSA) are risk factors for atrial fibrillation (AF), but the underlying mechanisms are poorly understood.
OBJECTIVE The purpose of this study was to assess the mechanisms underlying AF promotion by obesity and OSA in rat models.
METHODS Zucker obese rats (ORs) and lean rats (LRs) were intubated and ventilated with air and 2% isoflurane. OSA was mimicked by stopping the ventilator and closing the airway for 40 seconds. For nonobstructive control periods, the protocol was repeated with an open airway. Fifteen seconds after apnea onset, AF susceptibility was tested with 6 atrial burst pacing cycles (25 Hz, 3 seconds, 1-second intercycle pauses).
RESULTS AF was not inducible in ORs or LRs at baseline or in nonobstructive control periods. AF was induced in 24 of 28 ORs (85.7%) vs 5 of 18 LRs (27.8%) during obstructive apnea (P &lt;.001). Negative intrathoracic pressure generation (esophageal pressure monitoring) was substantial during obstructive apnea. Echocardiography showed left ventricular hypertrophy with diastolic dysfunction in ORs. Obstructive apnea caused acute left atrial (LA) dilation, increasing LA diameter significantly more in ORs than in LRs. To clarify AF mechanisms, 24 AF-inducible ORs were divided into 4 groups: saline (n = 5), pharmacologic autonomic blockade (n = 7), respiratory muscle paralysis with rocuronium (n = 6), and inferior vena cava (IVC) balloon occlusion to unload the LA (n = 6). Balloon catheter-induced IVC occlusion prevented LA distension during obstructive apnea, leading to 83.3% AF prevention (P &lt;.05). Rocuronium also was protective (66.7%), but autonomic blockade had smaller effects (42.9% prevention).
CONCLUSION Obesity and acute obstructive apnea interacted to promote AF in this model. Forced inspiration-induced acute LA distension related to diastolic dysfunction may be an important component of the arrhythmogenic substrate for AF during OSA episodes in obese patients.

DOI： 10.1016/j.hrthm.2012.03.024

Web of Science

PubMed

researchmap

記述言語：英語   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

DOI： 10.1161/CIRCULATIONAHA.111.075432

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Atrial fibrillation (AF), the most common sustained cardiac arrhythmia, is an important contributor to population morbidity and mortality. An arrhythmia that is particularly common in the elderly, AF is growing in prevalence with the aging of the population. Our understanding of the basic mechanisms that govern AF occurrence and persistence has been increasing rapidly. This article reviews the basic pathophysiology of AF over a broad range of levels, touching on the tissue mechanisms that maintain the arrhythmia, the relationship between clinical presentation and basic mechanisms, ion channel and transporter abnormalities that lead to ectopic impulse formation, basic models and tissue determinants of reentry, ion channel determinants of reentry, the nature and roles of electric and structural remodeling, autonomic neural components, anatomic factors, interactions between atrial and ventricular functional consequences of AF, and the basic determinants of atrial thromboembolism. We then review the potential implications of the basic pathophysiology of the arrhythmia for its management. We first discuss consequences for improved rhythm control pharmacotherapy: targeting underlying conditions, new atrium-selective drug targets, new targets for focal ectopic source suppression, and upstream therapy aiming to prevent remodeling. We then review the implications of basic mechanistic considerations for rate control therapy, AF ablation, and the prevention of thromboembolic events. We conclude with some thoughts about the future of translational research related to AF mechanisms. (Circulation. 2011;124:2264-2274.)

DOI： 10.1161/CIRCULATIONAHA.111.019893

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The Brugada-type electrocardiogram (ECG) is characterized by ST-segment elevation in the right precordial ECG leads and has been reported to have the potential of sudden death. Right ventricular outflow tract supplied from the conus branch of the coronary artery (CB) is considered as the anatomopathologic substrate of Brugada syndrome. We experienced two asymptomatic patients with a saddleback Brugada-type ECG who exhibited a dynamic ECG conversion to a coved type following a ventricular fibrillation/ventricular tachycardia (VT/VF) episode when myocardial ischemia occurred exclusively at the CB. Some types of Brugada syndrome might be caused VT/VF by selective myocardial ischemia at the CB. (PACE 2011
34:e26-e29) © 2010 Wiley Periodicals, Inc.

DOI： 10.1111/j.1540-8159.2010.02742.x

Scopus

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Background-Coronary artery disease predisposes to atrial fibrillation (AF), but the effects of chronic atrial ischemia/infarction on AF-related substrates are unknown.
Methods and Results-Regional right atrial myocardial infarction (MI) was created in 40 dogs by ligating an artery that supplies the right atrial free wall and not the ventricles; 35 sham dogs with the same artery isolated but not ligated were controls. Dogs were observed 8 days after MI and subjected to open-chest study, in vitro optical mapping, and/or cell isolation for patch-clamp and Ca(2+) imaging on day 8. Holter ECGs showed more spontaneous atrial ectopy in MI dogs (eg, 662+/-281 on day 7 versus 34+/-25 ectopic complexes per day at baseline; 52+/-21 versus 1+/-1 atrial tachycardia episodes per day). Triggered activity was increased in MI border zone cells, which had faster decay of caffeine-evoked Ca(2+) transients and enhanced (by approximate to 73%) Na(+)-Ca(2+) exchange current. Spontaneous Ca(2+) sparks (confocal microscopy) occurred under beta-adrenergic stimulation in more MI dog cells (66+/-9%) than in control cells (29+/-4%; P&lt;0.01). Burst pacing induced long-lasting AF in MI dogs (1146+/-259 versus 30+/-14 seconds in shams). Increased border zone conduction heterogeneity was confirmed by both bipolar electrode mapping in vivo and optical mapping. Optical mapping demonstrated stable border zone reentry in all 9 MI preparations but in none of 6 shams. Border zone tissue showed increased fibrous tissue content.
Conclusions-Chronic atrial ischemia/infarction creates substrates for both spontaneous ectopy (Ca(2+)-release events, increased Na(+)-Ca(2+) exchange current) and sustained reentry (conduction abnormalities that anchor reentry). Thus, chronic atrial infarction in dogs promotes both AF triggers and the substrate for AF maintenance. These results provide novel insights into potential AF mechanisms in patients with coronary artery disease. (Circulation. 2011;123:137-146.)

DOI： 10.1161/CIRCULATIONAHA.110.972778

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: Cardiac resynchronization therapy (CRT) with a single RV and LV lead (CRT with 2V) includes proarrhythmic effect from an increase the transmural dispersion of repolarization, and antiarrhythmic effect from ventricular reverse remodeling. CRT with triple-site biventricular stimulation with a single RV and two LV leads (CRT with 3V) might reduce the ventricular arrhythmias (VAs). Methods: The study included 55 patients with a CRT defibrillator. Prior to implantation, acute hemodynamic effect of CRT with 2V and 3V were measured by an invasive electrophysiologic study and 3V was introduced when better response was achieved. Spontaneous VAs detected by the device were reviewed with a follow-up of 12 months. Results: Hemodynamic study indicated 19 patients (34.5%) eligible for CRT with 3V. At 12 months follow up, 15 patients (27.2%) experienced VAs. We developed logistic regression model to identify variables associated with risk of VAs. Reduction rate of LV end-systolic volume were identified between CRT with 2V and 3V (18.8 ±34.0% vs. 16.3±25.1% p=0.52). Nonetheless, CRT with 3V showed a significant reduction in VAs (odds ratio 0.095, 95 percent confidence interval 0.084 to 0.108
p=0.01). Conclusions: CRT with 3V was associated with a reduction in VAs independent of LV reverse remodeling. Keywords: cardiac resynchonization therapy, multisite pacing, ventricular tachycardia. © 2011, Japanese Heart Rhythm Society. All rights reserved.

DOI： 10.4020/jhrs.27.OP06_7

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE CIRCULATION SOC  

Background: Although clinical studies have suggested a link between inflammation markers and atrial fibrillation (AF), it is still unclear whether local immunologic responses actually exist in human atria during AF.
Methods and Results: To address this point, human left appendages were obtained from 16 patients who underwent cardiac surgery (5 with sinus rhythm (SR) and 11 with AF) and subjected to immunohistochemical analysis. In all the AF specimens, adhesion and migration of CD45-reactive cells were consistently observed predominantly in the atrial endo- and subendomyocardium and more prominently than in SR. Most of them were immunologically active CD68-positive macrophages, whereas CD3-positive T cells infiltrated to a lesser extent. Scavenger-receptor A staining revealed maturation of macrophages not in the endocardium but in the midmyocardium, a gradient from endo- to midmyocardium. In the endocardium, along with adhesion molecules (intracellular adhesion molecule-1 and vascular cell adhesion molecule-1), a chemotactic protein-1, which facilitates the recruitment, was more abundantly expressed in AF than in SR. Cytokines including transforming growth factor-beta and interleukin-6 were frequently expressed by these macrophages.
Conclusions: These observations collectively imply active adhesion and recruitment of macrophages across the endocardium in human fibrillating atria, thereby supporting the concept of local immunologic inflammatory responses around the atrial endocardium of AF. (Circ J 2010; 74: 262-270)

DOI： 10.1253/circj.CJ-09-0644

Web of Science

PubMed

researchmap

記述言語：日本語   出版者・発行元：The Japanese Society of Electrocardiology  

Purkinje線維は刺激伝導に特化した筋線維組織である．虚血に対する耐性が強く，動物の心筋梗塞モデルにおいて残存Purkinje線維が心室頻拍（VT）の起源となることが知られている．ヒトにおいては心筋梗塞後の多形性VTや心室細動（VF）を誘発する期外収縮の発生源となるとともに，Purkinje線維網自体がその後のリエントリーの基質となりうることも判明している．正常心でも，ベラパミル感受性特発性左室VTや特発性VFにPurkinje線維が関与している．一方，Ligament of Marshall（LOM）は左大静脈の遺残構造物であり，心筋線維を含むため，心房頻拍や心房細動に関連した異常自動能の発生源となるとともに，左房や肺静脈との間に多数の連結点を有することで心房性不整脈の基質となる．これら微細な構造物の描出は現在の画像診断の精度では不十分であり，不整脈との関連においては不明点が多い．今後の画像診断の精度向上に期待する．

DOI： 10.5105/jse.30.275

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

Sarcoidosis is a systemic granulomatous disorder whose prognosis worsens when the heart is involved, and cart diagnosis is important. Endomyocardial biopsy is the most helpful diagnostic examination, but suffers from low sensitivity and low specificity. Micro-volt T wave alternans (MVTWA) is utilized in noninvasive examinations to detect beat-to-beat changes in the shape of the T wave at the microvolt level. Such beat-to-beat T wave changes arise from beat-to-beat changes in the transmural gradient of action potential duration. We speculate that the granulomatous changes of cardiac sarcoidosis produce cell-to-cell uncoupling and augment the transmural gradients of action potential duration.
To examine the clinical significance of MVTWA in the prediction of cardiac involvement in sarcoidosis patients, we obtained MVTWA in a total of 35 sarcoidosis patients with and without cardiac involvement. All patients underwent electrocardiography (ECG), ambulatory electrocardiography, chest radiography, transthoracic echocardiography, and MVTWA examination using a CH 2000 system. We diagnosed cardiac sarcoidosis in 7 patients according to the accepted diagnostic criteria. MVTWA was detected in 6 out of 7 cardiac sarcoidosis patients (85.7%) as opposed to in 2 out of 28 patients without cardiac involvement (7.1%). The difference between the two groups was statistically significant (P &lt; 0.001). The sensitivity and specificity of MVTWA in cardiac sarcoidosis detection were 85.7% and 92.8%, respectively. The positive and negative predictive values were 75% and 96.3%, respectively, with in overall accuracy of 91.4%.
Noninvasive examination of MVTWA using a CH 2000 is a useful diagnostic tool for detecting cardiac involvement in patients with sarcoidosis. (Int Heart J 2009; 50: 731-739)

DOI： 10.1536/ihj.50.731

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-BLACKWELL PUBLISHING, INC  

Methods: This study consisted of AFL (group 1, N = 15) and non-AFL patients (group 2, N = 13). The CT structural characteristics were determined with intracardiac echocardiography. A 20-pole electrode catheter was located along the CT and pacing at progressively faster rates from either low anterolateral right atrium (LRA) or coronary sinus (CS) was applied.
Results: The CT height, width, and area were significantly greater in group 1 than in group 2 (P &lt; 0.001). In both groups, at the longest pacing cycle length during CS pacing resulting in CT transverse conduction block at some levels, the width and area were significantly greater at the levels with block than at those without block. During LRA pacing, the area was also significantly larger at the levels with block than at those without in group 1, but not in group 2. The slope angle of CT ridge was significantly steeper at the levels with block than at those without in both groups (P &lt; 0.01), but that was not the case with CS pacing. CT arborization in its inferior portion was more frequently documented in group 1 than group 2 (P &lt; 0.05).
Conclusions: The CT structural characteristics that may influence its transverse conduction differ between LRA and CS pacing. Steep slope and arborization of the CT are implicated as a geometric factor in its transverse conduction block.
(PACE 2009; 32:868-878).

DOI： 10.1111/j.1540-8159.2009.02402.x

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：INT HEART JOURNAL ASSOC  

Septic shock has been reported as an independent risk factor for atrial fibrillation (AF), however, the mechanism remains Unknown. We investigated whether lipopolysaccharide (LPS) could alter cardiac ion channel gene expression, thereby leading to atrial arrhythmogenesis.
LPS (2.5 mg/kg) was injected intraperitoneally into 10 week old Sprague-Dawley rats (n = 5). Hemodynamic data were obtained and the atrial appendages were removed after LPS injection (0, 3, 6, 12, and 24 hours) for ail RNase protection assay for alpha 1C, beta 2, alpha 1G, and SCN5A. An electrophysiological Study in isolated perfused hearts was performed before and 12 hours after the LPS injection. Heart rate and body temperature were significantly increased (P &lt; 0.05) and mean blood pressure wits slightly decreased (P &lt; 0.1) at 12 hours after LPS injection. The mRNA levels of the L-type calcium channel gene (beta 2 and alpha 1C) were significantly decreased at 6 and 12 hours after LPS injection. Atrial ERP became significantly shortened and the number of repetitive atrial responses induced by all extrastimulus were significantly increased after LPS injection.
LPS induced the down-regulation of L-type calcium channel gene expression and ERP shortening, which might be a mechanism underlying sepsis-induced AF (hit Heart J 2009; 50: 353-363)

DOI： 10.1536/ihj.50.353

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE CIRCULATION SOC  

Background: Inflammatory processes in the atria during systemic inflammation remain unclear, so this study tested the hypothesis that macrophages infiltrate the atria] myocardium mainly through the atrial endocardium with the contribution of fractalkine.
Methods and Results: Sprague-Dawley rats were injected with lipopolysaccharide (LPS) to simulate inflammation in the atria. Inflammation was immunohistologically assessed by the presence of macrophages. Macrophage infiltration was diffuse throughout the atrial myocardium after LPS injection. At an earlier phase after LPS injection, the number of macrophages dramatically increased, mainly in the atrial endocardium, and the expression of fractalkine protein was markedly increased by treatment with LPS in the atrial endocardium. The LPS-induced increase in atrial macrophage infiltration was significantly suppressed by neutralizing the fractalkine protein (P&lt;0.01).
Conclusions: In an experimental model of atrial inflammation, macrophages infiltrated the myocardium mainly through the atrial endocardium with the contribution of fractalkine. Inhibition of macrophage infiltration by suppressing chemokine expression could be a novel therapeutic approach to controling acute inflammation in the atria. (Circ J 2009; 73: 932-937)

DOI： 10.1253/circj.CJ-08-0856

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Most paroxysmal atrial fibrillation (PAF) ultimately becomes chronic atrial fibrillation (CAF), even in the presence of antiarrhythmic drugs. Upstream therapies such as calcium channel blockers (CCB), angiotensin-converting enzyme inhibitors (ACEI), or statins have attracted attention for treating AF patients. We have previously reported that ACEI inhibited the progression of PAF to CAF. CCB and statins were also reported to inhibit the development of AF, but the follow-up periods in several of the papers appeared to be too short to allow a clear verdict on the antiarrhythmic effects. We therefore conducted a retrospective analysis of the relationship between long-term treatment (over 5 years) with an ACEI, CCB, or statin and outcome in patients with PAF (n = 125).The follow-up period was 7.7 +/- 3.1 years. Class I antiarrhythmic drugs were prescribed for 76.6% of the patients, ACEI for 36.0%, CCB for 47.2%, and statins for 20.0%. We assessed the cardiac rhythm from the medical records or electrocardiograms and determined the time from the first visit to the development of CAF. Kaplan-Meier analysis showed that the use of an ACEI significantly decreased the cumulative probability of CAF, while class I antiarrhythmics, CCB, and statins did not inhibit progression to CAF. Multivariate analysis showed that only ACEI was related to a reduced progression to CAF (odds ratio, 0.112; 95% confidence interval, 0.034 to 0.374, P = 0.001). Class I antiarrhythmic drugs, CCBs, and statins showed no such association.ACEI thus appear to be superior to CCB or statins with respect to upstream therapy.

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE CIRCULATION SOC  

Background A novel modified tissue-type plasminogen activator, monteplase, has been approved for acute major pulmonary embolism (PE) in Japan. Monteplase has rapid and sustained lytic effects because of a steep rise in concentration after bolus infusion and a longer half-life.
Methods and Results To assess the efficacy and safety of thrombolysis with monteplase in combination with catheter-based treatment, acute hemodynamic changes and clinical outcomes were assessed in 50 patients with angiographically confirmed major PE. Thrombolysis with monteplase in combination with embolus fragmentation and thrombectomy was the acute phase treatment. The study population comprised 31 females and 19 males (mean age 62 years). All patients had right ventricular (RV) overload; 12 patients presented in shock. The mean pulmonary artery pressure decreased significantly from 32 +/- 9 mmHg to 25 +/- 6 mmHg after acute phase treatment (P&lt;0.0001). The mean dosage of monteplase was 12,265 IU/kg. Death at 30 days occurred in 3 patients (6%). Major bleeding occurred in 12 patients (24%). RV overload at discharge remained in only 3% of the patients with typically acute onset.
Conclusions Thrombolysis with monteplase. in combination with catheter-based treatment, is an effective and safe therapy for major PE.

DOI： 10.1253/circj.CJ-08-0660

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1272/jnms.75.252

Scopus

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE CIRCULATION SOC  

Background Contrast-induced nephropathy (CIN) frequently complicates cardiac catheterization, so the objectives of present study were to investigate the usefulness of cystatin C before catheterization and establish a cut-off level for CIN, and to examine the changes in cystatin C and several other markers in patients with and without CIN.
Methods and Results Prospective Study of consecutive 87 patients who underwent elective catheterization: moderate renal disease defined as glomerular filtration rate 30-59 ml.min(-1)1.73 mm(-2). cystatin C and creatinine (Cr), urinary liver-type fatty acid-binding protein (L-FABP), alpha 1, beta 2 microglobulins, N-acetyl-beta-D-glucosaminidase, and microalbumin were measured immediately before, and 1, 2, and 3 days after catheterization. CIN occurred in 18 patients and receiver-operating characteristic analysis showed a higher area-under-the-curve for cystatin C compared with serum Cr (0.933 vs 0.832 p=0.012). At a cut-off level of &gt; 1.2 mg/L, cystatin C before catheterization exhibited 94.7% (95% confidence interval: 0.851-1.015) sensitivity and 84.8% specificity for detecting CIN. Cystatin C levels were higher in CIN patients than in those without CIN, even before catheterization (cystatin C: 1.08 +/- 0.22 vs 1.36 +/- 0.28 mg/L, p=0.007). Urinary L-FABP was increased on days 1 and 2 in patients with moderate renal disease.
Conclusion Cystatin C was useful for predicting the occurrence of CIN. Urinary L-FABP was the only marker of transient renotubular damage.

DOI： 10.1253/circj.CJ-07-1006

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BLACKWELL PUBLISHING  

Background: The transient atrial rhythm intervened between atrial flutter (AFL) and its termination during class III antiarrhythmic drug therapy for AFL has not been characterized well.
Methods: Eighteen patients with typical AFL were included in this study. The transient atrial rhythms converted from AFL with different class III antiarrhythmic drugs, ibutilide (group 1, N = 8) and nifekalant (group 2, N = 10), were determined.
Results: AFL terminated, without any intervened transient atrial rhythms, due to conduction block within the isthmus in three patients in each group. The transient atrial rhythm could be characterized into the following types of rhythm based on the initiating mechanisms. (1) The lower-loop reentry or atrial fibrillation that was triggered by a premature excitation in the lateral right atrium caused by breakdown of a functional barrier predisposed AFL to the termination in three patients in each group. (2) The return excitation that repetitively emerged within the isthmus collided with the antegrade excitation, resulting in the termination in two group 1 patients and in one group 2 patient. In the patients who developed these atrial rhythms, the cycle length (CL) oscillation coincidently increased with emergence of such rhythms and became significantly greater than that in the patients who did not develop such transient rhythms (P &lt; 0.05).
Conclusions: The transient atrial rhythms that emerged with class III drugs are associated with the disruption of the stable AFL reentry that may be triggered by similar electrophysiologic mechanisms with different class III drugs. The increased flutter CL oscillation developing after such drugs might signal the AFL termination.

DOI： 10.1111/j.1540-8159.2008.01120.x

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE CIRCULATION SOC  

The use of automated external defibrillators (AEDs) has increased the number of survivors of out-of-hospital cardiac arrest. The AED has a high specificity and moderately high sensitivity in detecting rhythms appropriately treated by defibrillation. However, a few shockable rhythms are misdiagnosed by the AED. Two cases of inappropriate analyses by AEDs in patients with in-hospital ventricular fibrillation are presented. In the first case, the AED failed to recognize ventricular fibrillation because of the presence of pacemaker spikes. In the second case, the fine ventricular fibrillation and the presence of artifacts were suspected as the causes of inappropriate analysis by the AED. Both patients were resuscitated by advanced cardiovascular life support with a manual defibrillator. Trained healthcare providers should be aware of the limitations of AED in specific situations.

DOI： 10.1253/circj.72.679

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Background: The clinical and electrophysiological characteristic of ventricular premature contractions (VPCs) which trigger the incessant form of polymorphic ventricular tachycardia (VT), so-called “electrical storm” associated with ischemic heart disease, remains unclarified. The aim of this study was to evaluate those matters and the possible role of the Purkinje network in the emergence of an electrical storm. Methods and results: We experienced 5 patients (68 ±5 years, mean LVEF: 29%) with electrical storms which occurred during the acute phase of an infarction in 3 patients and the remote phase in 2. The triggering VPCs were multifocal in 3 patients and monofocal in the remaining 2. Radiofrequency (RF) catheter ablation was performed for a goal of eliminating the triggering VPCs. A total of 9 different kinds of VPCs differentiated by their morphology were successfully eliminated by the RF deliveries targeting the VPCs— foci. At the successful ablation sites, Purkinje potentials preceded the QRS onset of the VPC by 67 ±23 ms, suggesting the VPCs originated in the surviving Purkinje fibers. Moreover, the extensive RF deliveries applied at the surviving Purkinje network rendered the polymorphic VT unable to be induced by programmed stimulation which reproducibly induced it before the ablation in 2 patients. Conclusion: A surviving Purkinje network might contribute not only to the initiation of the repetitive form of lethal ventricular arrhythmias, but also to the perpetuation of the arrhythmias in patients with ischemic heart disease. © 2008, Japanese Heart Rhythm Society. All rights reserved.

DOI： 10.4020/jhrs.24.200

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：J R A A S LTD  

Introduction. Atrial fibrillation (AF) per se causes atrial endocardial dysfunction leading to local coagulation imbalance on the internal surface of the atrium, which contributes to thrombus formation in the fibrillating left atrium.
Materials and methods. To test a hypothesis that blockade of angiotensin 11 type I receptor (AT(1)-receptor) prevents the endocardial dysfunction by AF, we examined the effects of olmesartan on the expression of tissue factor pathway inhibitor (TFPI), thrombomodulin (TM), endothelial nitric oxide synthase (eNOS) and plasminogen activator inhibitor-1 (PAI-1) in the endocardium of the rapidly paced rat atria.
Results. Rapid pacing induced a significant decrease in TFPI, TM and eNOS and an increase in PAI-1 protein in the left atrium. Pre-administration of low-dose olmesartan significantly prevented the down-regulation of TFPI, TM and eNOS and also attenuated the up-regulation of PAI-1. Immunohistochemistry identified these changes predominantly in the atrial endocardium. While the drug was without any effect on mRNA levels of TFPI,TM and eNOS, there was a significant decrease in its PAI-1 mRNA expression.
Conclusions. AT(1)-receptor blocker could partially prevent the atrial endocardial dysfunction by rapid atrial pacing, which would provide one theoretical basis for beneficial effects for stroke prevention in AF.

DOI： 10.3317/jraas.2007.021

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：OXFORD UNIV PRESS  

Aims Drinking alcohol is known to be one of the triggering factors of neurally-mediated syncope. Little is known about the diagnostic utility of the conventional and alcohol provocation head up tilt-test (HUT) in patients with alcohol-related syncope. We investigated the effect of the alcohol provocation HUT
Methods and results We studied 12 patients (8 mates, age 51 +/- 19 years) who had a history of unexplained post-alcohol ingestion syncope. An alcohol provocation protocol HUT (alcohol HUT), in which the protocol required 350 mL of 5% alcohol beer to be drunk over 5 min followed by positioning with the table tilted up for up to 30 min, was performed after the control and isoproterenol (ISP) HUT None of the subjects (0/12) exhibited a positive response in the control HUT, and only one subject had a positive response (1/12; 8.3%) in the ISP HUT In the alcohol HUT a positive response (9/12; 75%) increased in the patient group, whereas there were no positive responses in the normal control group.
Conclusion In the conventional HUT protocols, including ISP provocation, it was difficult to produce a positive response in the patients with alcohol-related syncope. Alcohol ingestion was a useful diagnostic provocation method in such patients.

DOI： 10.1093/europace/eum025

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：OXFORD UNIV PRESS  

Aims Various pathological conditions can alter cardiac electrophysiological properties not only by physiological. responses but also by modifying the gene expression of ion channels (electrical remodelling). To investigate the underlying mechanisms of the tatter, electrophysiological alterations would require a simultaneous and comprehensive analysis of the nnRNA level of the ion channel genes.
Methods and results We designed 19 cardiac ion channel cDNA templates to analyse the corresponding mRNAs and classified them into three template sets. Those sets were a voltage-dependent K+ channel series (rat erg, KvLQT1, Kv4.3, Kv4.2, Kv2.1, Kv1.5, Kv1.4, Kv1.2), an inwardly rectifying K+ channel series (rat Kir6.2, SUR2A/B, Kir3.4, Kir3.1, Kir2.2, Kir2.1), and an inward cationic ion channel series (rat SCN5A, alpha 1C, beta 2, alpha 282 of cardiac L-type Ca2+ channel and alpha 1G). These cDNA templates were used to synthesize antisense digoxigenin-labelled RNA probes. An amount of the total RNA of 25 mu g was adequate to analyse simultaneously the mRNA levels of the ion channel genes with the use of multi-probe RPA, and these three multi-probe template sets enabled us to evaluate the profile of the spatial and temporal transcripts of the cardiac ion channels.
Conclusion The newly developed ion channel multi-probe RPA templates provide an aid in the comprehensive analysis of the electrical remodelling of the heart.

DOI： 10.1093/europace.eul099

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE INC  

BACKGROUND Other thin bundle branch reentry and interfascicular reentry, monomorphic postmyocardial infarction (post-MI) reentrant ventricular tachycardia (VT) including the His-Purkinje system has not been reported. Verapamil-sensitive idiopathic left VT includes the left posterior Purkinje fibers but develops in patients without structural heart disease.
OBJECTIVES The purpose of this study was to describe a novel mechanism of reentrant VT arising from the Left posterior Purkinje fibers in patients with a prior MI.
METHODS The study consisted of four patients with a prior MI and symptomatic heart failure who underwent etectrophysiologic study and catheter ablation for VT showing right bundle branch block (n = 3) or atypical left bundle branch block (n = 1) morphology with superior axis. In two patients, the VT frequently emerged during the acute phase of MI and required emergency catheter ablation.
RESULTS Clinical VT was reproducibly induced by programmed stimulation. In three patients, both diastolic and presystolic Purkinje potentials were sequentially recorded along the left ventricular posterior septum during the VT, whereas in the fourth patient, only presystolic Purkinje potentials were observed. During entrainment pacing from the right atrium, diastolic Purkinje potentials were captured orthodromically and demonstrated decremental conduction properties, whereas presystolic Purkinje potentials were captured antidromically and appeared between the His and QRS complex. Radiofrequency energy delivered at the site exhibiting a Purkinje-QRS interval of 58 +/- 26 ms successfully eliminated the VTs without provoking any conduction disturbances.
CONCLUSION Reentrant monomorphic VT originating from the Left posterior Purkinje fibers, which is analogous to idiopathic left VT, can develop in the acute or chronic phase of MI. Catheter ablation is highly effective in eliminating this VT without affecting Left ventricular conduction.

DOI： 10.1016/j.hrthm.2006.04.019

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE INC  

BACKGROUND Because the anatomic features of the cavotricuspid isthmus (CTI) are complex, radiofrequency (RF) energy requirements for CTI ablation may vary at each point within the CTI. Conventionally, multiple-site mapping has been required for determining CTI conduction block.
OBJECTIVES The purpose of this study was to develop a more efficacious method for ablation of isthmus-dependent atrial flutter.
METHODS Forty consecutive patients underwent CTI ablation using a CTI mapping-guided approach (20 patients) or a conventional approach (20 patients). In the CTI mapping-guided approach, an octapolar catheter was positioned on the CTI parallel to, and downstream from, the intended ablation tine in order to map and ablate the breakthrough point.
RESULTS Complete CTI block was achieved in all study patients. CTI mapping of incomplete ablation tines revealed that the site with the shortest interval between double potentials did not always coincide with the conduction gap. Disappearance of a breakthrough pattern on the CTI electrograms corresponded to creation of complete CTI block. During ablation, CTI mapping exhibited pseudo-CTI block in 8% of patients in the clockwise direction and 63% of patients in the counterclockwise direction. The number and total time of RF applications were significantly tower with the CTI mapping-guided approach than with the conventional approach (7.7 +/- 3.9 applications vs 13.8 +/- 8.9 applications and 8.9 +/- 4.4 minutes vs 16.3 +/- 11.9 minutes, respectively, P &lt; .05). In the CTI mapping-guided approach, RF applications were not required along the entire CTI in 7 patients (35%).
CONCLUSION This simplified technique was feasible for creating and determining complete CTI block, with fewer RF applications required.

DOI： 10.1016/j.hrthm.2006.02.008

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE CIRCULATION SOCIETY  

BACKGROUND: Many pathological conditions induce electrical remodeling, possibly through intracellular Ca2+ overload, but the currently available L-type Ca2+ channel blockers may be detrimental because of their global negative inotropic effects. METHODS AND RESULTS: To determine whether the L-type Ca2+ channel is identical throughout the heart, the distribution of the mRNAs and proteins comprising the L-type Ca2+ channel and its electrophysiological properties were analyzed in rat atria and ventricles. The mRNA of alpha2delta-2 (Cacna2d2) was more abundantly expressed in the atrium (approximately 5-fold) than in the ventricle. In contrast, alpha1C (Cacna1c) (Cav1.2) mRNA was significantly less abundant in the atrium. The level of the alpha1C (Cacna1c) (Cav1.2) protein was decreased (approximately 0.5-fold) and that of alpha2 delta-1 (Cacna2d1) was increased (approximately 2-fold) in the atrium compared with the ventricle. Although the peak ICa,L density showed no significant differences, voltage dependence of inactivation and activation of the current showed a more depolarized shift in the atrium than in the ventricle. CONCLUSION: These results indicate that in the rat heart the L-type Ca2+ channel differs between the atrium and ventricle with regard to gene expression and electrophysiological properties.

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Percutaneous aortic valvuloplasty is reportedly a useful tool for the management of critical and severe aortic stenosis with cardiogenic shock 1. However, early percutaneous coronary intervention for cardiogenic shock is beneficial for elderly patients with acute myocardial infarction 2,3. We describe a patient with critical aortic stenosis who presented with severe coronary stenosis of the left main trunk and the ostium of the right coronary artery. We performed percutaneous coronary intervention and percutaneous aortic valvuloplasty under intra-aortic balloon pump and percutaneous cardiopulmonary support. After these procedures, the cardiogenic shock was reversed, and the patient could be weaned from both intra-aortic balloon pump support and percutaneous cardiopulmonary support.

DOI： 10.1272/jnms.73.158

Scopus

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOC INTERNAL MEDICINE  

Leukocytopenia can be caused by depressed production, increased peripheral destruction, or excessive peripheral pooling. Leukocyte margination is one of the mechanisms responsible for excessive peripheral pooling. A reversible leukocyte margination is caused by an increase in pro-inflammatory cytokines. However, there are limited data for this phenomenon in clinical conditions. We describe a case of unexpected transient leukocytopenia after exchanging an extracorporeal membrane oxygenation (ECMO) system used to treat severe cardiogenic pulmonary edema. To assess the cause of the leukocytopenia, the serum concentrations of pro-inflammatory cytokines and selectins were measured. The concentrations of tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-8 were markedly, but transiently, elevated in relation to the leukocytopenia. The transient leukocytopenia with pulmonary margination appeared to be caused by a steep surge of pro-inflammatory cytokines stimulated by hypoxia/reoxygenation during the exchange of the ECMO system. This case may suggest the mechanisms responsible for leukocytopenia in the clinical entity referred to as "systemic inflammatory response syndrome".

DOI： 10.2169/internalmedicine.45.6088

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOC INTERNAL MEDICINE  

A 64-year-old man with repetitive gastrointestinal bleeding was admitted to our hospital. Colonic artery angiography revealed angiodysplasia as the bleeding site, and echocardiography showed aortic valve stenosis. A decrease in the high molecular weight von Willebrand factor multimers, which are known to play an important role in hemostasis, was observed, and Heyde syndrome was diagnosed. We selected colectomy instead of aortic valve replacement because the patient had undergone two open heart surgeries. Following colectomy, the patient showed a good clinical course without recurrent gastrointestinal bleeding. Colectomy might serve as a therapeutic option for Heyde syndrome after the precise site of angiodysplasia is detected by angiography.

DOI： 10.2169/internalmedicine.45.1526

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BLACKWELL PUBLISHING  

Ablation of LVOT Tachycardia from a Coronary Vein.
We report a case of idiopathic left ventricular outflow tract (LVOT) tachycardia that was eliminated by a radiofrequency application from the anterior interventricular coronary vein (AIV). The ECG exhibited QRS complexes with an inferior axis and atypical left bundle branch block pattern with an early transition of the precordial R waves at V3. Several radiofrequency applications from the coronary cusps and endocardial LVOT were not effective. Radiofrequency applications in the AIV, where the activation preceded the onset of the QRS by 30 msec, successfully eliminated the tachycardia. The AIV may be an optional site for radiofrequency ablation of idiopathic epicardial LVOT tachycardia.

DOI： 10.1111/j.1540-8167.2005.00257.x

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE INC  

Background Atrial tachycardia (AT) can originate from the proximal coronary sinus (CS). However, detailed electrophysiologic characteristics of the tachycardia are not available.
Objectives We describe the electrophysiologic characteristics, response to adenosine 5'-triphosphate, and results of radiofrequency ablation of AT with the earliest activation in the proximal CS.
Methods In 7 of 54 patients (age 57 +/- 18 years) with nonmacroreentrant "focal" AT undergoing electrophysiologic study and radiofrequency ablation, the earliest atrial activation site was located in the proximal CS.
Results The earliest activation site was inside the CS 13 +/- 3 mm from the ostium. The AT could be induced and terminated by atrial extrastimuli or burst pacing. In all patients, the AT was also terminated by a very small dose of adenosine 5'-triphosphate (4.2 +/- 1.1 mg). Rapid ventricular pacing during the tachycardia produced ventriculoatrial dissociation. Radiofrequency ablation directed at the earliest atrial activation site was effective in only three patients (group A). In the remaining four patients (group 13), after the radiofrequency energy deliveries, the earliest activation site shifted to an adjacent site with a small increase in the cycle length. Three group B patients underwent successful ablation in the slow pathway region. No recurrence was observed over a follow-up period of 22 +/- 5 months.
Conclusion AT with earliest activation in the proximal CS is sensitive to a small dose of adenosine 5'-triphosphate. In some patients, radiofrequency applications in the slow pathway region are effective even if the local activation is not early.

DOI： 10.1016/j.hrthm.2005.08.030

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPANESE CIRCULATION SOCIETY  

BACKGROUND: Atrial fibrillation is a progressive disease, which in the paroxysmal form (PAF) becomes more frequent and finally becomes chronic (CAF). A retrospective analysis of patients with PAF was conducted to examine the hypothesis that angiotensin-converting enzyme inhibitors (ACEI) will prevent the progression to CAF. METHODS AND RESULTS: On the basis of their treatment, 95 patients with PAF were divided into 2 groups: 42 patients treated with ACEI for hypertension throughout the period of treatment and follow-up (ACEI group) and 53 patients not given ACEI (non-ACEI group). Cardiac rhythms were assessed either from the medical records or the electrocardiograms recorded every 2-4 weeks at follow-up visits. The mean follow-up time was 8.3+/-3.5 years. There was no significant difference in the use of antiarrhythmic drugs, left atrial diameter or left ventricular ejection fraction between the 2 groups. The Kaplan-Meier curve for the time to occurrence of CAF showed a lower incidence of CAF in the ACEI group and demonstrated that the 5-year probability for persistence of PAF without progression to CAF was 88.3%, but 47.5% in the non-ACEI group. CONCLUSIONS: These results indicate that ACEI will prevent progression from PAF to CAF.

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：INTERNATIONAL HEART JOURNAL ASSOCIATION  

Antiarrhythinic drugs exert their effects by inhibiting the ion channels of cardiomyocytes. However. these effects could also modify the ionic environment around them, and thereby affect the expression of ion channels, leading to biochemical enhancement or attenuation of the antiarrhythmic effects. To test this hypothesis, the physiological and biochemical effects of cibenzoline were evaluated in a rapid atrial pacing model in rats.
In rats with rapid atrial pacing, pretreatment with cibenzoline significantly inhibited the increases in Kv1.5 mRNA at 2 hours and immunoreactive protein at 4 hours by 35 +/- 15% and 30 +/- 10%, respectively. These effects were observed only in the rapid atrial pacing group, not in the sham-operated group. Willi cibenzoline pretreatment. 4-hour rapid atrial pacing resulted in significant prolongation of the atrial refractory period compared to the untreated group even after removal of cibenzoline. In contrast, the sham and rapid atrial pacing model with and without cibenzoline pretreatment showed similar acute physiological responses to cibenzoline.
In conclusion, in addition to the acute physiological effects, pretreatment with cibenzoline exerted pleiotropic effects of inhibition of Kv1.5 channel upregulation by rapid pacing, implying differences in the cibenzoline effects when administered before and after onset of paroxysmal atrial fibrillation.

DOI： 10.1536/ihj.46.279

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BLACKWELL FUTURA PUBLISHING, INC  

An anomalous inferior vena cova (IVC) is often associated with patients with dextrocardia. However, radiofrequency catheter ablation in Such a case with that combination has not been reported. We encountered a case of Wolff-Porkinson-White syndrome with dextrocardia associated with complete situs inversus and an azygos continuation of the IVC. A steep angulation at the junction of the azygos vein and superior vena cava precluded the precise mapping of the anatomical right cavity with a femoral vein approach. Successful catheter ablation of an accessory connection between the coronary sinus and left ventricle could be achieved with a right cubital vein approach.

DOI： 10.1111/j.1540-8159.2005.09510.x

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Introduction: Due to the difficulty in performing detailed mapping around the tricuspid annulus and the high occurrence of mechanical trauma during the procedure, the outcome of right-sided accessory pathway (AP) ablation still has a relatively high primary failure and recurrence rate. Methods and Results: Six patients with right free-wall APs underwent electroanatomical mapping. The AP had retrograde unidirectional conduction in 3 patients, anterograde unidirectional conduction in 1 patient, and bidirectional conduction in 2 patients. The right atrial (RA) activation map was constructed during right ventricular (RV) pacing (n = 5), and the RV activation map was constructed during RA pacing (n = 3). During mapping, the AP conduction was interrupted by catheter mechanical trauma in 3 patients. The first RF application successfully eliminated the AP conduction within 2 seconds in 3 patients with concealed pathways. In the remaining 3 patients, rescue RF energy was delivered at the tagged bump site on the map. The mean procedure time was 214 ± 77 minutes, and mean fluoroscopy time 63 ± 23 minutes. No recurrence occurred during 12 ± 3.2 months of follow-up in any of the patients. Conclusions: With the guidance of an electroanatomical mapping system, right-sided accessory pathways can be satisfactorily eliminated without later recurrence. © 2005, Japanese Heart Rhythm Society. All rights reserved.

DOI： 10.4020/jhrs.21.459

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BLACKWELL FUTURA PUBLISHING, INC  

This case report describes a patient with Wolff-Parkinson-White syndrome in whom the ECG exhibited a typical pattern Of on anteroseptal (superoparaseptal) accessory pathway. Successful radiofrequency catheter ablation was achieved from the septal side of the left ventricular outflow tract. It might be worthwhile to map the left side of the anterior septum if on accessory pathway potential is not appreciable along the tricuspid annulus to ovoid the potential complication of AV block in patients with a typical anteroseptal accessory pathway ECG pattern.

DOI： 10.1111/j.1540-8159.2004.00505.x

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BLACKWELL FUTURA PUBLISHING, INC  

The purpose of the present study was to assess the influence of autonomic blockade on shortening of effective refractory period (ERP) induced by short-term rapid atrial pacing (RAP) and its recovery process. Fifteen patients (8 men, 7 women, age 52 +/- 16 years) without structural heart disease and without a history of atrial fibrillation were included in this study. All patients underwent RAP at a cycle length of 300 ms for 5 minutes, after which the ERP was measured in all patients at 1, 3, 5, 7.5, and 10 minutes following cessation of RAP. In ten patients, these RAP and measurements of ERPs were repeated after administration of propronolol (P) and subsequent administration of atropine (P + A), respectively. In the remaining five patients atropine (A) was given first and then the administration of propranolol followed (P + A). Relative to the baseline value, the ERP immediately after RAP did not differ significantly from the Control(G), P, A, or P + A (C, 79% +/- 8%; P, 82% +/- 9%; A, 80% +/- 6%; P + A, 82% +/- 13%). However, the ERP 3 minutes after cessation of RAP was significantly (P &lt; 0.05) longer in A (93% +/- 4%) and P + A (97% +/- 5%) than that in C (86% +/- 5%) and P (86% +/- 5%). The recovery time for ERP to return to pre-RAP value was significantly shorter during A and P + A than during either G or P (C, 536 +/- 161 s; P, 503 +/- 172 s; A, 282 +/- 111 s; P + A, 291 +/- 147 s; P &lt; 0.05). Parasympathetic blockade may promote recovery from ERP shortening induced by short-term RAP.

DOI： 10.1111/j.1540-8159.2004.00382.x

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Background-Atrial fibrillation (AF) is well known as one of the cardiogenic causes for thromboembolism. Although decreased flow and hypercoagulable state of the blood in the fibrillating atrium have been emphasized as the underlying mechanisms, endocardial dysfunction in maintaining the local coagulation balance could also contribute to the thrombogenesis in AF.
Methods and Results-The paroxysmal AF model was created by rapid atrial pacing in anesthetized rats. To test the hypothesis that AF induces local coagulation imbalance by disturbing the atrial endocardial function, the gene expression of intrinsic anticoagulant factors, thrombomodulin (TM) and tissue factor pathway inhibitor (TFPI), were determined by means of ribonuclease protection assay, Western blotting, and immunohistochemistry. Rapid atrial pacing for 8 hours significantly decreased TM and TFPI mRNA levels in the left atrium but not in the ventricle, leading to the downregulation of their immunoreactive proteins. Immunohistochemical analysis revealed that TM and TFPI were expressed predominantly in the endocardial cells of the normal atrium, presumably preventing local blood coagulation, and that rapid atrial pacing induced the loss of TM and TFPI expression in the endocardium, leading to deficiency in anticoagulant barriers between the atria and the blood.
Conclusions-Rapid atrial pacing acutely downregulated the gene expression of TM and TFPI in the atrial endocardium, thereby inducing local coagulation imbalance on the internal surface of the atrial cavity. These results would support the validity of supplement of anticoagulant molecules deficient in AF.

DOI： 10.1161/01.CIR.0000102969.09658.F2

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BLACKWELL FUTURA PUBLISHING, INC  

Introduction: Ventricular arrhythmias induced during electrophysiologic study (EPS) may vary over time, making arrhythmia induction studies unreliable. The aim of this prospective study was to clarify the clinical significance of long-term variability in induced arrhythmias and to elucidate factors determining this variability.
Methods and Results: Three noninvasive EPSs were performed 1, 13, and 25 months after implantation of a cardioverter defibrillator in 40 patients with ventricular tachyarrhythmias, without a change in their antiarrhythmic drug regimens. The induced ventricular arrhythmias were categorized into five grades. Long-term variability, which was defined as a variation in the grades during the three EPSs, was observed in 23 patients (group A) and not in the remaining 17 patients (group B). During the 2-year period, spontaneous sustained ventricular arrhythmias developed in 15 patients (65%) in group A but in only 4 patients (24%) in group B (P = 0.01). Inducibility of sustained tachyarrhythmias was not associated with emergence of spontaneous arrhythmias. All patients also underwent thallium-201 and iodine-123-metaiodobenzylguanidine (MIBG) scans to evaluate the extent of the regions showing normal thallium uptake with reduced MIBG uptake. Group A patients showed greater thallium/MIBG mismatched regions than did group B patients (P = 0.01). Logistic regression analysis revealed that long-term variability (relative risk [RR] 7.55, P = 0.03), amiodarone therapy (RR 0.14, P = 0.04), and left ventricular ejection fraction &lt;35% (RR 6.26, P = 0.04) were independent predictors of spontaneous arrhythmia occurrence.
Conclusion: In patients with ventricular tachyarrhythmias, long-term variability in induced arrhythmias, but not the inducibility of arrhythmias, is associated with a higher incidence of spontaneous arrhythmias. Regional cardiac sympathetic denervation may be an important mechanism of this variability. These results also may explain why inducibility-based antiarrhythmic drug testing does not predict patient prognosis.

DOI： 10.1046/j.1540-8167.2003.03164.x

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：LIPPINCOTT WILLIAMS & WILKINS  

Background-Many cardiac arrhythmias have their own characteristic circadian variations. Because the expression of many genes, including clock genes, is regulated variably during a day, circadian variations of ion channel gene expression, if any, could contribute to the fluctuating alterations of cardiac electrophysiological characteristics and subsequent arrhythmogenesis.
Methods and Results-To examine whether cardiac K+ channel gene expression shows a circadian rhythm, we analyzed the mRNA levels of 8 Kv and 6 Kir channels in rat hearts every 3 hours throughout 1 day. Among these channels, Kv1.5 and Kv4.2 genes showed significant circadian variations in their transcripts: approximate to2-fold increase of Kv1.5 mRNA from trough at Zeitgeber time ( ZT) 6 to peak at ZT18 and a completely reverse pattern in Kv4.2 mRNA (approximate to2-fold increase from trough at ZT18 to peak at ZT6). Actually, along with the variations in the immunoreactive proteins, the density of the transient outward and steady-state currents in isolated myocytes and the responses of atrial and ventricular refractoriness to 4-aminopyridine in isolated-perfused hearts showed differences between ZT6 and ZT18, a circadian pattern comparable to that of Kv1.5 and Kv4.2 gene expression. Reversal of light stimulation almost inverted these circadian rhythms, although pharmacological autonomic blockade only partially attenuated the rhythm of Kv1.5 but not of Kv4.2 transcripts.
Conclusions-Among all the cardiac K+ channels, Kv1.5 and 4.2 channels are unique in showing characteristic circadian patterns in their gene expression, with Kv1.5 increase during the dark period partially dependent on beta-adrenergic activities and Kv4.2 increase during the light period independent of the autonomic nervous function.

DOI： 10.1161/01.CIR.0000058752.79734.F0

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：FUTURA PUBL CO  

Bidirectional Conduction Property of Low RA Isthmus. Introduction: It has been shown that the induction rates of common and reversed common atrial flutter are comparable during baseline control study, whereas the rate is significantly greater for common flutter than reversed common flutter during administration of antiarrhythmic agents. The mechanism of this discrepancy is not known.
Methods and Results: The study consisted of 15 patients (group 1) with clinically documented common atrial flutter either with (n = 10) or without (n = 5) Class I antiarrhythmic therapy, and 15 patients with paroxysmal supraventricular tachycardia (group 2). Bidirectional conduction velocity and minimal pacing cycle length of 1:1 conduction during incremental pacing from both the low lateral right atrium and coronary sinus were assessed. The response of these variables to procainamide was analyzed in correlation with the induction rate of each type of flutter during the pacing protocol. Conduction velocity in the clockwise (CW) direction was significantly slower for all pacing cycle lengths than conduction velocity in the counterclockwise (CCW) direction in group 1 but was similar in group 2. Minimal pacing cycle length of 1: 1 conduction did not differ between CW and CCW conduction in either group. However, in group 1, minimal pacing cycle length of 1:1 conduction of CW conduction was prolonged to a greater degree after procainamide than that of CCW conduction. There also was a significant increase in the induction rate of common flutter. This preferential effect of procainamide on CW conduction was not observed in group 2.
Conclusion: CW conduction over the isthmus is preferentially influenced by procainamide compared with CCW conduction, which may explain the greater incidence and induction probability of common flutter during antiarrhythmic therapy.

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：KLUWER ACADEMIC PUBL  

A detailed analysis of the ventricular activation along the posterior aspect of the mitral annulus was made using a multipolar catheter positioned in the coronary sinus in a patient with mitral isthmus ventricular tachycardia (VT) associated with a remote inferior myocardial infarction and prior cryosurgical ablation for the elimination of a different preexisting VT. A change in the timing and sequence of the ventricular activation along the isthmus could be observed during induction of the VT and entrainment pacing. A radiofrequency (RF) current application directed at the posterolateral region of the isthmus successfully eliminated this tachycardia. During the RF delivery, complete conduction block was confirmed by a sudden change in the activation sequence during sinus rhythm.

Web of Science

researchmap

記述言語：日本語   出版者・発行元：The Japanese Society of Clinical Pharmacology and Therapeutics  

DOI： 10.3999/jscpt.29.75

CiNii Books

researchmap

その他リンク： http://search.jamas.or.jp/link/ui/1998161074

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：日本臨床生理学会  

researchmap

記述言語：日本語   出版者・発行元：(公社)日本整形外科学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本心臓病学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本心臓病学会  

researchmap

記述言語：日本語   出版者・発行元：日本内科学会-関東地方会  

researchmap

記述言語：日本語   出版者・発行元：日本内科学会-関東地方会  

researchmap

記述言語：日本語   出版者・発行元：日本整形外科超音波学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本心血管インターベンション治療学会  

researchmap

記述言語：日本語   出版者・発行元：日本内科学会-関東地方会  

researchmap

記述言語：日本語   出版者・発行元：(一社)中部日本整形外科災害外科学会  

researchmap

記述言語：日本語   出版者・発行元：臨床心臓電気生理研究会  

researchmap

記述言語：日本語   出版者・発行元：(一社)中部日本整形外科災害外科学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本糖尿病学会  

researchmap

記述言語：日本語   出版者・発行元：(有)科学評論社  

researchmap

記述言語：日本語   出版者・発行元：(有)科学評論社  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本不整脈心電学会  

早期再分極パターン(ER-ECG pattern)はJ波とも呼ばれ、日常診療でよくみられる心電図所見である。従来予後良好とされてきたが、近年、種々の基礎心疾患を有する症例で致死性不整脈との高い関連性が報告されている。しかし、急性心筋炎におけるER-ECG patternと致死性不整脈との関連は不明であり、今回その関連を検討し、心臓磁気共鳴画像(CMR)所見に基づいた機序の洞察を行った。急性心筋炎患者30症例(平均年齢39.2歳、男性23例)において、9症例で心筋炎急性期のみ一過性に限局したER-ECG patternを呈し(ER群)、これらの心筋傷害は軽度であった。CMRのT2強調画像ではER-ECG patternの誘導に近接する左室心外膜側に限局した高信号を認めた。一方、ER-ECG patternを伴わないST上昇や異常Q波を呈する残りの21例(non-ER群)では心筋傷害は高度で、T2高信号域は左室全周性に及んだ。劇症化例では致死性不整脈が発生したが、ER-ECG patternを呈した例では1例もなかった。急性心筋炎では、心外膜側に限局した炎症や浮腫が心内膜-心外膜間の電気的勾配を形成し、ER-ECG patternをきたす成因の一つと考えられた。急性心筋炎におけるER-ECG patternは一過性かつ可逆性であり、心筋傷害も心外膜側に限局しているため劇症化することなく経過し、致死性不整脈との関連はなかった。(著者抄録)

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本脊椎脊髄病学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本内科学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本内科学会  

researchmap

記述言語：日本語   出版者・発行元：(株)日本臨床社  

researchmap

記述言語：日本語   出版者・発行元：(株)日本臨床社  

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：日本末梢神経学会  

researchmap

記述言語：日本語   出版者・発行元：日本サルコイドーシス  

researchmap

記述言語：日本語   出版者・発行元：日本サルコイドーシス  

researchmap

記述言語：日本語   出版者・発行元：日本内科学会-関東地方会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本心臓病学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本睡眠学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本心臓病学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本心臓病学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本集中治療医学会  

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：日本語   出版者・発行元：(公社)日本薬剤師会  

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：日本医科大学医学会  

researchmap

その他リンク： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2021&ichushi_jid=J04260&link_issn=&doc_id=20210702400001&doc_link_id=10.1272%2Fmanms.17.96&url=https%3A%2F%2Fdoi.org%2F10.1272%2Fmanms.17.96&type=J-STAGE&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00007_3.gif

記述言語：日本語   出版者・発行元：日本内科学会-関東地方会  

researchmap

記述言語：日本語   出版者・発行元：(有)科学評論社  

researchmap

記述言語：日本語   出版者・発行元：(公社)日本超音波医学会  

researchmap

J-GLOBAL

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：日本語   出版者・発行元：(株)メジカルビュー社  

＜文献概要＞Point 1 カテーテルアブレーション単独による心房細動治療の限界。2 カテーテルアブレーション後の心房細動再発予防における生活管理。3 医学・医療技術が進歩した時代での心房細動治療の原点回帰。

J-GLOBAL

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

BACKGROUND: The development of heart failure is associated with fluid balance, including that of extracellular water (ECW) and intracellular water (ICW). This study determined whether sodium-glucose cotransporter 2 inhibitors affect fluid balance and improve heart failure in patients after acute myocardial infarction. METHODS AND RESULTS: EMBODY was a prospective, randomized, double-blinded, placebo-controlled trial of Japanese patients with acute myocardial infarction and type 2 diabetes. Overall, 55 patients who underwent bioelectrical impedance analysis were randomized to receive once daily 10 mg empagliflozin or placebo 2 weeks after acute myocardial infarction onset. We investigated the time course of body fluid balance measured using the bioelectrical impedance analysis device, InBody. The primary end points were changes in body fluid balance from weeks 0 to 24. Changes between baseline and week 24 in the empagliflozin and placebo groups were -0.21 L (P = .127) and +0.40 L (P = .001) in ECW (P = .001) and -0.23 L (P = .264) and +0.74 L (P < .001) in ICW (P < .001), respectively. In a stratified analysis, the rise in ECW and ICW was significantly attenuated in the empagliflozin group in contrast to the placebo group in participants with a body mass index of 25 or higher but not in those with a body mass index of less than 25. CONCLUSIONS: Early sodium-glucose cotransporter 2 inhibitor administration may attenuate changes in ECW and ICW.

DOI： 10.1016/j.cardfail.2021.07.022

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

Atrial fibrillation (AF) is a common arrhythmia in patients with hypertrophic cardiomyopathy (HCM) and is associated with renal function deterioration. The protective effects of catheter ablation (CA) of AF on renal function in patients with HCM remain unsolved. From 2009 to 2020, a total of 169 consecutive patients with HCM and AF (age 70 ± 12, 87 males) were retrospectively evaluated. The estimated glomerular filtration rate (eGFR) was evaluated at the study enrollment or 1 month before the CA and reevaluated 3 and 12 months later. In the 169 patients, 63 underwent CA of AF (ablation group), and the remaining 106 did not (control group). After propensity score matching, 45 pairs were matched. The baseline eGFR was similar between the 2 groups (p = 0.83). During a mean follow-up period of 34 ± 27 months, sinus rhythm was maintained in 36 patients (80%) after 1.7 ± 0.8 ablation procedures. The eGFR significantly decreased from baseline to 3 months (p <0.01) and from baseline to 1 year (p <0.01) in the control group, whereas the eGFR in the ablation group was maintained both from baseline to 3 months (p = 0.94) and from baseline to 1 year (p = 1.00) after the CA. The change in the eGFR between baseline and 12 months was significantly smaller in the ablation group than in the control group (p <0.01). After logistic regression analysis, CA of AF was the independent predictor of an improvement of eGFR (odds ratio 2.81, 95% confidence interval 1.08 to 7.36, p = 0.04). In conclusion, CA of AF had a protective effect on renal function in patients with HCM.

DOI： 10.1016/j.amjcard.2022.02.055

PubMed

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：(株)メディカルレビュー社  

researchmap

記述言語：日本語   出版者・発行元：(株)メディカルレビュー社  

researchmap

その他リンク： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2020&ichushi_jid=J06376&link_issn=&doc_id=20201225180001&doc_link_id=%2Fai1ccoad%2F2020%2F000704%2F001%2F0186-0193%26dl%3D0&url=http%3A%2F%2Fwww.medicalonline.jp%2Fjamas.php%3FGoodsID%3D%2Fai1ccoad%2F2020%2F000704%2F001%2F0186-0193%26dl%3D0&type=MedicalOnline&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00004_2.gif

記述言語：日本語   出版者・発行元：(公財)日本心臓財団  

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：日本内科学会-関東地方会  

researchmap

記述言語：日本語   出版者・発行元：(株)南江堂  

＜文献概要＞▼高齢者では期外収縮,心房細動,徐脈性不整脈が多くみられ,超高齢社会を迎えたわが国では日常診療で出会う機会が多い.▼高齢者では腎機能低下や内服アドヒアランスの問題から,抗不整脈薬や抗凝固薬などの有害事象のリスクが高くなることがあり注意が必要である.▼カテーテルアブレーションやペースメーカーなどの侵襲的治療は有効性・安全性が向上してきており,治療選択肢としてあげられる.▼患者背景を含めリスクとベネフィットを評価して適応を判断し,十分なインフォームド・コンセントのもと治療方針を決定することが重要である.

J-GLOBAL

researchmap

その他リンク： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2020&ichushi_jid=J00974&link_issn=&doc_id=20201023160007&doc_link_id=issn%3D0022-1961%26volume%3D126%26issue%3D5%26spage%3D881&url=http%3A%2F%2Fwww.pieronline.jp%2Fopenurl%3Fissn%3D0022-1961%26volume%3D126%26issue%3D5%26spage%3D881&type=PierOnline&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00005_2.gif

記述言語：日本語   出版者・発行元：(株)じほう  

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：(株)じほう  

＜Points＞▼Na+チャネル遮断薬は抗不整脈薬の代表的な作用機序の一つで、わが国では10種類以上の薬剤が使用可能である。▼Na+チャネル遮断薬はVaughan Williams分類ではI群抗不整脈薬に分類され、一般的に伝導抑制作用は、心拍数が高いほど強くなる。心機能抑制や催不整脈作用があり、機序を理解した使用が肝要である。▼高齢者では腎機能低下や肝機能低下により、抗不整脈薬の血中濃度上昇を来すことがある。また、抗コリン作用をもつ薬剤では尿閉や緑内障の悪化、便秘や口渇などの副作用に注意が必要である。(著者抄録)

researchmap

その他リンク： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2020&ichushi_jid=J01465&link_issn=&doc_id=20201102230002&doc_link_id=%2Fan1yakgl%2F2020%2F006215%2F005%2F2911-2915%26dl%3D0&url=http%3A%2F%2Fwww.medicalonline.jp%2Fjamas.php%3FGoodsID%3D%2Fan1yakgl%2F2020%2F006215%2F005%2F2911-2915%26dl%3D0&type=MedicalOnline&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00004_2.gif

記述言語：日本語   出版者・発行元：日本内科学会-関東地方会  

researchmap

記述言語：日本語   出版者・発行元：日本内科学会-関東地方会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本老年医学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本老年医学会  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本老年医学会  

researchmap

記述言語：日本語   出版者・発行元：日本サルコイドーシス  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本老年医学会  

researchmap

記述言語：日本語   出版者・発行元：(株)学樹書院  

researchmap

記述言語：日本語   出版者・発行元：日本サルコイドーシス  

researchmap

記述言語：日本語   出版者・発行元：(公財)日本心臓財団  

researchmap

記述言語：日本語   出版者・発行元：(一社)日本不整脈心電学会  

心サルコイドーシスは脚ブロックや房室ブロックなどの伝導障害で発症することが多く、伝導異常を鋭敏に反映する加算平均心電図がその早期診断に有用である可能性がある。われわれは心電図正常の肺サルコイドーシス患者74例で加算平均心電図を記録分析し、その後の心イベントとの関連性を解析した。結果、29名(39.2%)が加算平均心電図においてLP陽性であった。平均9.8年のフォローアップ期間でLP陽性例のうち8例が心イベントを発症した(完全房室ブロック4例、心室頻拍2例、心不全2例)。一方、心室遅延電位陰性群では1例のみ(心不全)であった。多変量解析の結果、LPのみが独立した危険因子であった(ハザード比9.66、95%信頼区間1.20-78.01、p=0.033)。Kaplan-Meier法を用いた解析では、LP陽性患者は陰性患者に比し有意に心イベントを起こしやすい(log-lank、p=0.004)ことが判明した。以上の結果から、肺サルコイドーシスにおける心室遅延電位は、心イベントの早期予測に有用である可能性が示唆された。(著者抄録)

researchmap

その他リンク： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2020&ichushi_jid=J00681&link_issn=&doc_id=20200818280001&doc_link_id=10.5105%2Fjse.40.69&url=https%3A%2F%2Fdoi.org%2F10.5105%2Fjse.40.69&type=J-STAGE&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00007_3.gif

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：英語   出版者・発行元：(一社)日本循環器学会  

researchmap

記述言語：日本語   出版者・発行元：(株)ライフ・サイエンス  

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：(株)ライフ・サイエンス  

researchmap