Updated on 2025/06/24

写真a

 
Amitani Ryosuke
 
Affiliation
Nippon Medical School Hospital, Department of Cardiovascular Surgery, Assistant Professor
Title
Assistant Professor
External link

Papers

  • Case of left ventricular thrombus managed with thrombectomy with left ventricular reconstruction in a patient who had coronavirus disease 2019 infection. International journal

    Kenji Suzuki, Shun-Ichiro Sakamoto, Atsushi Hiromoto, Yusuke Motoji, Ryosuke Amitani, Takako Yamaguchi, Yosuke Ishii

    Journal of cardiothoracic surgery   18 ( 1 )   8 - 8   2023.1

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    BACKGROUND: Intracardiac thrombus is relatively rare in patients with coronavirus disease 2019 (COVID-19). However, if it occurs, thrombotic complications are likely to develop. In this case, we performed a successful thrombectomy on a patient who developed left ventricular thrombus after COVID-19 infection without complications. CASE PRESENTATION: A 52-year-old man sought medical care due to fever, dyspnea, and abnormalities in the taste and smell that persisted for 2 weeks. The patient was diagnosed with COVID-19 and was treated with remdesivir, baricitinib, and heparin. Three weeks after hospitalization, electrocardiogram revealed angina pectoris, and cardiac catherization showed left anterior descending coronary artery stenosis. In addition, global hypokinesis and a thrombus at the left ventricular apex were observed on echocardiography. Left ventricular reconstruction concomitant with coronary artery bypass grafting was performed. A thrombus in the left ventricle was resected via left apical ventriculotomy, and the bovine pericardium was covered and sutured on the infarction site to exclude it. The patient was extubated a day after surgery and was transferred to another hospital for recuperation after 20 days. He did not present with complications. CONCLUSIONS: Thrombotic events could be prevented via thrombectomy with left ventricular reconstruction using an intraventricular patch to exclude the residual thrombus.

    DOI: 10.1186/s13019-023-02108-5

    PubMed

    researchmap

  • Surgical Management of Cardiac Implantable Electronic Device Complications in Patients Unsuitable for Transvenous Lead Extraction.

    Yasuo Miyagi, Hiroya Oomori, Motohiro Maeda, Tomohiro Murata, Keisuke Ota, Yusuke Motoji, Ryosuke Amitani, Hitomi Ueda, Motoko Morishima, Takayoshi Matsuyama, Jiro Kurita, Yuji Maruyama, Takashi Sasaki, Shun-Ichiro Sakamoto, Yosuke Ishii

    Circulation journal : official journal of the Japanese Circulation Society   87 ( 1 )   103 - 110   2022.12

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    BACKGROUND: Although surgical approaches for infected or failing cardiac implantable electronic device (CIED) leads are more invasive than transvenous approaches, they are still required for patients considered unsuitable for transvenous procedures. In this study, surgical management with transvenous equipment for CIED complications was examined in patients unsuitable for transvenous lead extraction. METHODS AND RESULTS: We retrospectively examined 152 consecutive patients who underwent CIED extraction between April 2009 and December 2021 at the Department of Cardiovascular Surgery, Nippon Medical School. Nine patients (5.9%; mean [±SD] age 61.7±16.7 years) who underwent open heart surgery were identified as unsuitable for the isolated transvenous approach. CIED types included 5 pacemakers and 4 implantable cardioverter-defibrillators; the mean [±SD] lead age was 19.5±7.0 years. Indications for surgical management according to Heart Rhythm Society guidelines included failed prior to transvenous CIED extraction (n=6), intracardiac vegetation (n=2), and severe lead adhesion (n=1). Transvenous CIED extraction tools were used in all patients during or before surgery. Additional surgical procedures with CIED extraction included epicardial lead implantation (n=4) and tricuspid valve repair (n=3). All patients were discharged; during the follow-up period (mean 5.7±3.7 years), only 1 patient died (non-cardiac cause). CONCLUSIONS: Surgical procedures and transvenous extraction tools were combined in the removal strategy for efficacious surgical management of CIED leads. Intensive surgical procedures were safely performed in patients unsuitable for transvenous extraction.

    DOI: 10.1253/circj.CJ-22-0456

    PubMed

    researchmap

  • Surgical Treatment of a Giant Popliteal Venous Aneurysm and Arteriovenous Fistula on the Adjacent Femoral Vein and Its Postoperative Findings.

    Atsushi Hiromoto, Shun-Ichiro Sakamoto, Yusuke Motoji, Ryosuke Amitani, Takako Yamaguchi, Kenji Suzuki, Hiromasa Yamashita, Makoto Watanabe, Eitaro Kodani, Yosuke Ishii

    Annals of vascular diseases   15 ( 3 )   197 - 200   2022.9

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    A case of a giant popliteal venous aneurysm that caused massive pulmonary thromboembolism with an arteriovenous fistula draining into the adjacent proximal femoral vein is reported herein. Deep veins in the lower leg were occluded by thrombi. The inlet and outlet orifice inside the aneurysm was closed and aneurysmorraphy was performed. The fistula was retained on the estimation that it would maintain the blood flow and prevent thrombus formation inside the femoral vein. The aneurysm was shrunk, the femoral vein was patent, and the fistula was not observed 1 year later, although it still existed 1 week after the operation.

    DOI: 10.3400/avd.cr.22-00044

    PubMed

    researchmap

  • Combined cardiac surgery in a Marfan syndrome patient with severe scoliosis via lower hemisternotomy: a case report.

    Shun-Ichiro Sakamoto, Ryosuke Amitani, Yusuke Motoji, Takako Yamaguchi, Atsushi Hiromoto, Kenji Suzuki, Yosuke Ishii

    Surgical case reports   8 ( 1 )   140 - 140   2022.7

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    BACKGROUND: Scoliosis is one of the symptoms manifested by patients with Marfan syndrome (MFS). Deformity of the thoracic cavity due to severe scoliosis may cause difficulty during cardiac surgery in terms of the surgical approach and instrument manipulation; however, only a few reports have been available regarding the surgical case of MFS with severe scoliosis. Here, we report a case of combined aortic valve replacement and left atrial appendage closure in a patient with MFS who had severe scoliosis using lower hemisternotomy. CASE PRESENTATION: A 62-year-old female with MFS was referred to our hospital after being diagnosed with severe aortic regurgitation and paroxysmal atrial fibrillation with a history of cerebral thromboembolism. The aortic valve showed severe insufficiency due to cusp prolapse, whereas the aortic root was moderately dilated (42 mm). Echocardiography revealed severe regurgitation with reduced left ventricular ejection function (32%) and massive left ventricular diastolic dimension (88 mm). Moreover, combined aortic valve replacement and left atrial appendage closure was indicated. However, the patient had chest deformity due to severe scoliosis. Thus, conventional full sternotomy or thoracotomy was considered an inappropriate surgical approach. Lower hemisternotomy was selected on the basis of three-dimensional reconstruction imaging of the aorta, left atrial appendage, sternum, and rib. Sternal elevation and rib retraction with the costal arch folded back provided enough surgical field for the combined procedures to be safely conducted. The postoperative course was uneventful, except for predicted prolonged mechanical ventilation with the assistance of intraaortic balloon pumping. Thereafter, the patient has been free from any cardiac and cerebrovascular event. CONCLUSIONS: Lower hemisternotomy can be useful for combined cardiac surgery in MFS with severe scoliosis.

    DOI: 10.1186/s40792-022-01504-8

    PubMed

    researchmap

  • Postoperative Changes in Pulmonary Function after Valve Surgery: Oxygenation Index Early after Cardiopulmonary Is a Predictor of Postoperative Course. International journal

    Tomohiro Murata, Motohiro Maeda, Ryosuke Amitani, Atsushi Hiromoto, Makoto Shirakawa, Masaru Kambe, Yuji Maruyama, Hajime Imura

    Journal of clinical medicine   10 ( 15 )   2021.7

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    OBJECTIVE: To determine pulmonary functional changes that predict early clinical outcomes in valve surgery requiring long cardiopulmonary bypass (CPB). METHODS: This retrospective study included 225 consecutive non-emergency valve surgeries with fast-track cardiac anesthesia between January 2014 and March 2020. Blood gas analyses before and 0, 2, 4, 8, and 14 h after CPB were investigated. RESULTS: Median age and EuroSCORE II were 71.0 years (25-75 percentile: 59.5-77.0) and 2.46 (1.44-5.01). Patients underwent 96 aortic, 106 mitral, and 23 combined valve surgeries. The median CPB time was 151 min (122-193). PaO2/FiO2 and AaDO2/PaO2 significantly deteriorated two hours, but not immediately, after CPB (both p < 0.0001). Decreased PaO2/FiO2 and AaDO2/PaO2 were correlated with ventilation time (r2 = 0.318 and 0.435) and intensive care unit (ICU) (r2 = 0.172 and 0.267) and hospital stays (r2 = 0.164 and 0.209). Early and delayed extubations (<6 and >24 h) were predicted by PaO2/FiO2 (377.2 and 213.1) and AaDO2/PaO2 (0.683 and 1.680), measured two hours after CPB with acceptable sensitivity and specificity (0.700-0.911 and 0.677-0.859). CONCLUSIONS: PaO2/FiO2 and AaDO2/PaO2 two hours after CPB were correlated with ventilation time and lengths of ICU and hospital stays. These parameters suitably predicted early and delayed extubations.

    DOI: 10.3390/jcm10153262

    PubMed

    researchmap

  • Response to letter by Dr. Imamura: implication of urine aquaporin-2 levels following cardiac surgery.

    Masahiro Fujii, Ryosuke Amitani, Ryuzo Bessho

    Heart and vessels   36 ( 3 )   431 - 431   2021.3

     More details

  • Perioperative urinary excretion of aquaporin-2 dependent upon vasopressin in cardiac surgery.

    Masahiro Fujii, Ryosuke Amitani, Ryuzo Bessho

    Heart and vessels   35 ( 5 )   712 - 718   2020.5

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    Aquaporin-2 is found in the apical cell membranes of the principal cells of the collecting duct of the kidney. Plasma arginine vasopressin has been reported to be markedly elevated during cardiac surgery. However fluctuations in urine aquaporin-2 levels have never been reported. We aimed to determine the responses of urine aquaporin-2 and evaluated the relationship between urine aquaporin-2 and plasma arginine vasopressin levels during perioperative periods in cardiac surgical patients. Eight patients undergoing elective isolated aortic valve replacement in normothermia were enrolled prospectively. Blood and urine samples were collected preoperatively and on postoperative days 1, 4, and 7. Patients received furosemide and spironolactone, as needed, during the clinical course; tolvaptan was not needed. Median plasma arginine vasopressin levels [with interquartile range] significantly increased to 1.5 [1.3-2.0], 15.3 [11.4-22.2]*, 2.2 [2.1-2.3], 1.7 [1.5-1.9] pg/mL preoperatively, on postoperative days 1, 4, and 7, respectively (*: p = 0.0001). Similarly, levels of urine aquaporin-2 markedly increased in 3.4 [1.9-5.6], 25.8 [18.4-33.5]**, 9.3 [5.9-14.0], 5.4 [5.3-6.1] (ng/mL), respectively (**p = 0.0004). A significant correlation between plasma arginine vasopressin and urine aquaporin-2 was observed during the entire investigation (R2 = 0.616, p < 0.0001). Plasma arginine vasopressin and urine aquaporin-2 levels were significantly elevated on postoperative day 1 in patients who underwent aortic valve replacement with cardiopulmonary bypass. A significant correlation between plasma arginine vasopressin and urine aquaporin-2 was observed. Urine aquaporin-2 should be further investigated as a potential biomarker for postoperative cardiac dysfunction.

    DOI: 10.1007/s00380-019-01533-8

    PubMed

    researchmap

  • Long-term impact of critical silent cerebrovascular disease in patients undergoing coronary artery bypass surgery: a propensity score and multivariate analyses. International journal

    Hajime Imura, Yuji Maruyama, Ryosuke Amitani, Motohiro Maeda, Makoto Shirakawa, Takashi Nitta

    Perfusion   34 ( 2 )   147 - 153   2019.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    BACKGROUND: Cerebrovascular disease (CVD) with brain hypoperfusion is a strong risk factor for stroke. However, how this pathology influences long-term outcomes after coronary artery bypass graft (CABG) surgery is not known. METHODS: Magnetic resonance imaging/angiography (MRI/A) of the neck and brain was performed in 318 out of 575 consecutive CABG patients between May 2005 and April 2018. Critical CVD with chronic hypoperfusion was defined as multiple severe stenoses (⩾70%) and/or occlusion in the carotid and/or vertebral systems associated with reduced collateral flow due to severe contralateral and/or circle of Willis lesion. Fifty patients were identified to have this pathology (early results were previously reported). The entire cohort was followed up for 83.6 ± 53.7 months. Carotid endarterectomy was considered for symptomatic patients. Propensity matching was performed to compare long-term outcomes between patients with and without critical CVD. RESULTS: Patients with critical CVD at follow-up displayed significantly higher incidences of stroke than those without critical CVD (p=0.007), with an extremely high final incidence (approximately 40% at 8 years). However, survival (p=0.623) and incidences of major adverse cardiac events (MACE: myocardial infarction, coronary revascularization and all causes of death) (p=0.881) were similar. The Cox hazard model revealed that critical CVD was the strongest risk factor for stroke (p=0.000; hazard ratio 6.572; 95% confidence interval 2.657-16.258) while not affecting survival and MACE. CONCLUSION: Critical CVD was the strongest risk factor for long-term stroke after CABG. However, survival and MACE-free rates were equivalent in patients with critical CVD and those without critical CVD.

    DOI: 10.1177/0267659118813042

    PubMed

    researchmap

▼display all

Research Projects

  • Development of new myocardial regeneration therapy using platelet-rich plasma and biodegradable sustained-release gel

    Grant number:22K08927  2022.4 - 2027.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

      More details

    Grant amount:\2470000 ( Direct Cost: \1900000 、 Indirect Cost:\570000 )

    researchmap

  • Impact of aquaporin 7 deficiency on preconditioning effect

    Grant number:17K10740  2017.4 - 2020.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

    Ota Keisuke

      More details

    Grant amount:\4680000 ( Direct Cost: \3600000 、 Indirect Cost:\1080000 )

    In the study of ischemic preconditioning (IPC), (3 min ischemia + 5 min reperfusion) × 2 cycles were adopted as IPC manners. Hearts isolated from wild type (WT) and AQP7 knockout (KO) mice were set in a Langendorff perfused model, and the myocardial protective effect against 25-minute global ischemia was examined. The WT mice showed an improvement effect in the IPC group compared to the control group, but no difference was observed in the AQP7KO mice. In the pharmacological preconditioning (PPC) study, nicorandil (100 microM) was administered before ischemia. In both WT and AQP7KO mice, the superior cardioprotection was observed in the PPC group compared to the control group.

    researchmap

  • Study of water channel aquaporin for treatment of perioperative heart failure

    Grant number:16K10642  2016.4 - 2019.3

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

    Amitani Ryosuke

      More details

    Grant amount:\4810000 ( Direct Cost: \3700000 、 Indirect Cost:\1110000 )

    We examined changes in plasma AVP and urinary AQP2 during perioperative period (before operation, on the first, fourth and seventh postoperative day) in patients who underwent cardiac surgery using cardiopulmonary bypass. The plasma AVP showed a transient increase significantly on the first postoperative day, and turned to decrease on the fourth postoperative day. Urinary AQP2 excretion showed similar changes. In patients undergoing off-pump coronary artery bypass grafting, postoperative plasma AVP and urinary AQP2 levels were elevated similar to those with cardiopulmonary bypass. AQP7, a member of the aquaglyceroporin family that is permeated by glycerol and water, has been observed in cardiac tissue. We have investigated a protective efficacy of STH2 in an experimental preparation of isolated AQP7 knock-out murine hearts. We demonstrated the myocardial protection afforded by STH2 even through AQP7 was absent.

    researchmap