Publications by authors named "Ryuzo Sakata"

A 40-year-old male with Becker muscular dystrophy presented with severe mitral regurgitation and underwent mitral valve repair. Following the surgery, the patient became tachycardic and developed a continuous high-grade fever and hyperbilirubinemia. The patient's condition worsened and we eventually tested his thyroid levels and discovered abnormally high thyroid levels.

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Intraoperative conversion to cardiopulmonary bypass with its subsequent high mortality is a major concern associated with off-pump coronary artery bypass grafting (OPCAB). The impact of procedure volume on the incidence of intraoperative conversion, however, is poorly defined. This study therefore evaluated the effect of procedure volume on the incidence of conversion in OPCAB using nationwide data.

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A 32-year-old male patient was initially diagnosed with fibrosing mediastinitis. The patient subsequently developed severe dyspnea and was further diagnosed with constrictive pericarditis due to the extent of fibrosing mediastinitis around the heart. Therefore, the patient underwent surgical resection of the fibrotic tissue in the anterior mediastinum including the pericardium and the pleura.

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Background: Staphylococcus lugdunensis is a coagulase-negative Staphylococcus species, which are weak pathogenic bacteria generally. However, the acute and severe pathogenicity of Staphylococcus lugdunensis infective endocarditis may be due to the rapid growth of large vegetation and consequent valve destruction.

Case Presentation: The patient was an 81-year-old male who visited our hospital with chief complaints of low back pain and high fever.

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Background: In patients with severe coronary artery disease (CAD) requiring coronary revascularization, the prevalence of surgical ineligibility and its clinical effect on long-term outcomes remain unclear.

Methods and results: Among 15,939 patients with first coronary revascularization in the CREDO-Kyoto percutaneous coronary intervention (PCI)/coronary artery bypass grafting (CABG) registry cohort-2, we identified 3,982 patients with triple-vessel or left main disease (PCI: n=2,188, and CABG: n=1,794). Surgical ineligibility as documented in hospital charts was present in 142 (6.

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Objectives: The postoperative left ventricular end-systolic volume index and ejection fraction are benchmarks of surgical ventricular reconstruction but remain unpredictable. This study aimed to identify who could be associated with a higher long-term survival by adding surgical ventricular reconstruction to coronary artery bypass grafting than coronary artery bypass grafting alone (responders to surgical ventricular reconstruction).

Methods: The subjects were 293 patients (median age, 63 years; 255 men) who underwent coronary artery bypass grafting for ischemic heart disease with left ventricular dysfunction in 16 cardiovascular centers in Japan.

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To realize human induced pluripotent stem cell (hiPSC)-based cardiac regenerative therapy, evidence of therapeutic advantages in human-sized diseased hearts are indispensable. In combination with an efficient and simultaneous differentiation of various cardiac lineages from hiPSCs and cell sheet technology, we aimed to generate clinical-sized large cardiac tissue sheets (L-CTSs) and to evaluate the therapeutic potential in porcine infarct heart. We simultaneously induced cardiomyocytes (CMs) and vascular cells [vascular endothelial cells (ECs) and vascular mural cells (MCs)] from hiPSCs.

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This study investigated the safety and efficacy of a sustained release of basic fibroblast growth factor (bFGF) with biodegradable gelatin hydrogel sheets as therapeutic angiogenesis in canine chronic myocardial infarction (MI) models. Canine chronic MI model was induced by ligating the left anterior descending coronary artery and its diagonal branches. At 4 week post-induction, we applied either saline (Control group, n = 5) or 200 μg of bFGF (Treatment group, n = 6) soaked gelatin hydrogel sheets on the ischemic area of the left ventricular (LV) wall.

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Objectives: Most randomized controlled trials of off-pump versus on-pump coronary artery bypass grafting (CABG) have included limited numbers of patients with preoperative renal failure. This study was performed to evaluate the association between the clinical benefit of the off-pump technique and chronic kidney disease stage.

Methods: We analyzed 38,051 patients with chronic kidney disease who underwent primary nonemergent isolated CABG from 2013 to 2015 as reported in the Japan Cardiovascular Surgery Database-Adult section.

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Objectives: Little data are available with regard to valve selections in redo valvular surgery. We investigated the impact of valve types on late outcomes after redo mitral valve replacement (MVR).

Methods: We retrospectively reviewed 66 patients aged 50-69 (mean age 62.

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Aim: We reviewed our experience in redo valvular surgery to evaluate trends in short- and long-term outcomes.

Methods: We reviewed 414 patients (mean age, 62.8 ± 13.

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Background: The contemporary medications for secondary prevention like statins and antithrombotic agents are targeting to delay the progression of atherothrombosis. However, there is limited data on the relation between death and progressive coronary atherothrombosis. This study sought to evaluate what proportion of death after coronary revascularization is related to documented progressive coronary atherothrombosis.

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Objective: Recent studies demonstrate that microRNAs show promising potential, including angiogenesis, in therapeutic intervention. MicroRNA-126 (miR-126) is reported to regulate angiogenesis by blocking Sprouty-related EVH1 domain-containing protein 1 (SPRED1), an endogenous inhibitor of vascular endothelial cell growth factor. In this study, we investigated the angiogenic effects of the sustained release of miR-126 loaded with poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs) in a murine hindlimb ischemia model.

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Whether patients with severe aortic stenosis (AS) die because of AS-related causes is an important issue for the management of these patients. We used data from CURRENT AS registry, a Japanese multicenter registry, to assess the causes of death in severe AS patients and to identify the factors associated with non-cardiac mortality. We enrolled 3815 consecutive patients with a median follow-up of 1176 days; the 1449 overall deaths comprised 802 (55.

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Torsade de Pointes (TdP) is a lethal arrhythmia that is often drug-induced, thus there is an urgent need for development of models to test or predict the drug sensitivity of human cardiac tissue. Here, we present an in vitro TdP model using 3D cardiac tissue sheets (CTSs) that contain a mixture of human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes and non-myocytes. We simultaneously monitor the extracellular field potential (EFP) and the contractile movement of the CTSs.

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Objective: To elucidate the factors associated with high left ventricular mass index (LVMI) and to test the hypothesis that high LVMI is associated with worse outcome in severe aortic stenosis (AS).

Methods: We analysed 3282 patients with LVMI data in a retrospective multicentre registry enrolling consecutive patients with severe AS in Japan. The management strategy, conservative or initial aortic valve replacement (AVR), was decided by the attending physician.

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Background: Cardiopulmonary bypass (CPB) may induce systemic inflammatory responses causing acute lung injury. Recombinant human soluble thrombomodulin (rTM) is reported to attenuate the secretion of inflammatory cytokines and the high-mobility group box 1 (HMGB1) protein, which is critical in controlling systemic inflammation and apoptosis. We investigated the protective effects of rTM on CPB-induced lung injury in a rat model.

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Objectives: We reviewed reoperations following mitral valve repair (MVR) that used glutaraldehyde-treated autologous pericardium for mitral regurgitation (MR) to analyse the durability and risk factors for reoperation.

Methods: We retrospectively analysed 144 patients (mean age 57.9 years) who underwent MVR using glutaraldehyde-treated pericardium from March 1992 to December 2011.

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Objectives: Although conventional open repair is our preference for patients with aortic arch aneurysms, we have often chosen thoracic endovascular aneurysm repair (TEVAR) with a handmade branched stent graft (bTEVAR) in high-risk patients. The aim of this study was to compare the midterm clinical outcomes of our bTEVAR technique to those of the open repair.

Methods: Between January 2007 and December 2014, we treated 129 patients with aortic arch aneurysm by means of either conventional open repair (OPEN, n = 61) or bTEVAR (n = 68) at our institution.

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Background: The aim of this study was to assess the long-term outcomes of aortic valve replacement (AVR) with either mechanical or bioprosthetic valves according to age at operation.Methods and Results:A total of 1,002 patients (527 mechanical valves and 475 bioprosthetic valves) undergoing first-time AVR were categorized according to age at operation: group Y, age <60 years; group M, age 60-69 years; and group O, age ≥70 years). Outcomes were compared on propensity score analysis (adjusted for 28 variables).

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The current study describes a scalable, porous large-format engineered cardiac tissue (LF-ECT) composed of human induced pluripotent stem cells (hiPSCs) derived multiple lineage cardiac cells with varied 3D geometries and cell densities developed towards the goal of scale-up for large animal pre-clinical studies. We explored multiple 15 × 15 mm ECT geometries using molds with rectangular internal staggered posts (mesh, ME), without posts (plain sheet, PS), or long parallel posts (multiple linear bundles, ML) and a gel matrix containing hiPSC-derived cardiomyocytes, endothelial, and vascular mural cells matured in vitro for 14 days. ME-ECTs displayed the lowest dead cell ratio (p < 0.

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A 50-year-old man was admitted with fever and chill sensation 6 months ago. Transthoracic echocardiography (TTE) showed left and right coronary cusp prolapses and a thickened tissue of the aortic curtain. Congestive heart failure due to active infective aortic valve endocarditis was diagnosed, and he underwent aortic valve replacement.

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Blood vessels are essential components for many tissues and organs. Thus, efficient induction of endothelial cells (ECs) from human pluripotent stem cells is a key method for generating higher tissue structures entirely from stem cells. We previously established an EC differentiation system with mouse pluripotent stem cells to show that vascular endothelial growth factor (VEGF) is essential to induce ECs and that cyclic adenosine monophosphate (cAMP) synergistically enhances VEGF effects.

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Objectives: Although transcatheter aortic valve replacement (TAVR) is an excellent alternative procedure for high-risk patients with severe symptomatic aortic stenosis, it is often associated with life-threatening complications. We report on the emergency or elective use of veno-arterial extracorporeal membrane oxygenation (ECMO) to manage these complications.

Methods: Between December 2013 and February 2016, 46 patients underwent TAVR at our institution.

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