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Featured researches published by Ryoichi Miyazaki.


American Journal of Cardiology | 2018

Effect of Optimizing Guideline-Directed Medical Therapy Before Discharge on Mortality and Heart Failure Readmission in Patients Hospitalized With Heart Failure With Reduced Ejection Fraction

Tetsuo Yamaguchi; Takeshi Kitai; Takamichi Miyamoto; Nobuyuki Kagiyama; Takahiro Okumura; Keisuke Kida; Shogo Oishi; Eiichi Akiyama; Satoshi Suzuki; Masayoshi Yamamoto; Junji Yamaguchi; Takamasa Iwai; Sadahiro Hijikata; Ryo Masuda; Ryoichi Miyazaki; Yasutoshi Nagata; Toshihiro Nozato; Yuya Matsue

Guideline-directed medical therapy (GDMT) is recommended for patients with heart failure with reduced ejection fraction (HFrEF). However, the prognostic impact of medication optimization at the time of discharge in patients hospitalized with heart failure (HF) is unclear. We analyzed 534 patients (73 ± 13 years old) with HFrEF. The status of GDMT at the time of discharge (prescription of angiotensin converting enzyme inhibitor [ACE-I]/angiotensin receptor blocker [ARB] and β blocker [BB]) and its association with 1-year all-cause mortality and HF readmission were investigated. Patients were divided into 3 groups: those treated with both ACE-I/ARB and BB (Both group: n = 332, 62%), either ACE-I/ARB or BB (Either group: n = 169, 32%), and neither ACE-I/ARB nor BB (None group: n = 33, 6%), respectively. One-year mortality, but not 1-year HF readmission rate, was significantly different in the 3 groups, in favor of the Either and Both groups. A favorable impact of being on GDMT at the time of discharge on 1-year mortality was retained even after adjustment for covariates (Either group: hazard ratio [HR] 0.44, 95% confidence interval [CI] 0.21 to 0.90, p = 0.025 and Both group: HR 0.29, 95% CI 0.13-0.65, p = 0.002, vs None group). For 1-year HF readmission, no such association was found. In conclusion, optimization of GDMT before the time of discharge was associated with a lower 1-year mortality, but not with HF readmission rate, in patients hospitalized with HFrEF.


Journal of Cardiology | 2017

Prognosis of super-elderly healthy Japanese patients after pacemaker implantation for bradycardia

Tetsuo Yamaguchi; Takamichi Miyamoto; Takamasa Iwai; Junji Yamaguchi; Sadahiro Hijikata; Ryoichi Miyazaki; Naoyuki Miwa; Masahiro Sekigawa; Yasutoshi Nagata; Toshihiro Nozato; Yasuteru Yamauchi; Toru Obayashi; Mitsuaki Isobe

BACKGROUND The prognosis of super-elderly patients (age≥85 years) who undergo bradycardia pacemaker (PM) implantation remains unknown. METHODS We retrospectively enrolled 868 patients (men 49.0%, 76.6±10.6 years) who could walk unassisted and whose expected life expectancy was more than 1 year, receiving their first bradycardia PM implantation between January 1, 2006, and June 30, 2013. Clinical outcomes were compared between super-elderly patients (n=201, mean age 88.6±3.2 years) and younger patients (n=667, 73.0±9.3 years). RESULTS At the end of a median 1285-day follow-up, 128 patients (14.7%) died, of which 54 were cardiac deaths (42.2%). Mortality rates were similar between the groups (16.4% vs. 14.2%, log-rank p=0.56) and across different indications for implantation (atrio-ventricular conduction disturbance or sick sinus syndrome, p=0.59), initial rhythms (sinus rhythm or persistent atrial fibrillation, p=0.62), pacing modes (dual chamber pacing or VVI pacing, p=0.26), and ventricular lead positions (septum or apex, p=0.52). On Cox proportional hazard model analysis, hypertension [hazard ratio (HR)=1.74, 95% confidence interval (CI)=1.19-2.54, p=0.004], diabetes mellitus (HR=2.18, 95% CI=1.51-3.14, p<0.001), history of myocardial infarction (HR=3.59, 95% CI=2.49-5.16, p<0.001), and history of stroke (HR=2.26, 95% CI=1.51-3.37, p<0.001) were independent predictors for mortality. CONCLUSIONS The mortality rate of super-elderly patients who had no critical illnesses and were healthy enough to walk unassisted at the time of PM implantation was not inferior to that of younger patients. Prognosis was determined by comorbidities, but not by age, PM indication, initial rhythm, pacing leads, or mode.


Journal of Cardiology Cases | 2018

Hemorrhagic shock due to branch injury of the left internal thoracic artery two days after pericardiocentesis

Sadahiro Hijikata; Takamichi Miyamoto; Tetsuo Yamaguchi; Junji Yamaguchi; Takamasa Iwai; Keita Watanabe; Yuichiro Sagawa; Ryo Masuda; Ryoichi Miyazaki; Naoyuki Miwa; Yasutoshi Nagata; Toshihiro Nozato

Pericardiocentesis is a definitive strategy to remove pericardial effusion. In this report, we present a rare case of a 23-year-old man with sudden delayed hemorrhagic shock due to branch bleeding of the left internal thoracic artery (LITA) two days after undergoing pericardiocentesis. Angiography, embolization, and drainage were effective. As far as we know, this is the first report that shows delayed bleeding due to branch injury of the LITA as a possible complication after pericardiocentesis. <Learning objective: Pericardiocentesis using an apical approach under echocardiography is considered safe; however, in this case, unexpected complications after pericardiocentesis for hemorrhagic shock occurred. Patients who undergo pericardiocentesis should be observed in the hospital for several days. If sudden changes in vital signs occur, the underlying complications should also be considered, and it is important to act promptly and review the patients prior procedures.>.


Journal of Arrhythmia | 2018

Comparison of direct oral anticoagulants and warfarin regarding midterm adverse events in patients with atrial fibrillation undergoing catheter ablation

Yuichiro Sagawa; Yasutoshi Nagata; Tetsuo Yamaguchi; Takamasa Iwai; Junji Yamaguchi; Sadahiro Hijikata; Keita Watanabe; Ryo Masuda; Ryoichi Miyazaki; Naoyuki Miwa; Masahiro Sekigawa; Toshihiro Nozato; Kenzo Hirao

Oral anticoagulants, including direct oral anticoagulants (DOACs), are usually required in atrial fibrillation (AF) patients who are at a high risk of thromboembolism (TE), even if they had undergone catheter ablation (CA). Although several studies have reported the safety and efficacy of DOACs around CA in AF patients, there are only limited data regarding the midterm incidence of TE and bleeding complications post‐CA among AF patients treated with warfarin or DOACs.


Internal Medicine | 2018

Cardiac Magnetic Resonance Imaging of Very Late Intrapericardial Hematoma 8 Years after Coronary Artery Bypass Grafting

Tetsuo Yamaguchi; Masahiro Terashima; Chisato Takamura; Hironobu Sakurai; Kiyotoshi Ooishi; Tomoya Yoshizaki; Junji Yamaguchi; Sadahiro Hijikata; Takamasa Iwai; Yuichiro Sagawa; Keita Watanabe; Ryoichi Miyazaki; Ryo Masuda; Naoyuki Miwa; Masahiro Sekigawa; Nobuhiro Hara; Yasutoshi Nagata; Takamichi Miyamoto; Toru Obayashi; Toshihiro Nozato

A 55-year-old man presented with dyspnea, edema, and appetite loss. He had undergone coronary artery bypass grafting 8 years previously. He had jugular venous distention and Kussmauls sign. Contrast-enhanced cardiac magnetic resonance imaging (CMRI) demonstrated an intrapericardial mass compressing the right ventricular (RV) cavity. T1- and T2-weighted black-blood images showed a mass with heterogeneous high signal intensity and a thick and dark rim. The mass was considered to be a chronic hematoma. After pericardiotomy with surgical removal of the hematoma, CMRI showed the marked improvement of the RV function. Late intrapericardial hematoma is rare and CMRI is useful for making a differential diagnosis.


Case Reports | 2018

Platypnoea–orthodeoxia syndrome exacerbated by kyphosis progression

Takamasa Iwai; Takamichi Miyamoto; Ryoichi Miyazaki; Toshihiro Nozato

This is a case of an 86-year-old woman with gradually progressive dyspnoea and hypoxaemia that occurred after a cardiac surgery. It was underdiagnosed for several years, but diagnosis was triggered by the finding of hypoxaemia even during supplemental oxygen administration when in the upright position, such as when taking a shower, that rapidly improved when the patient returned to the supine position. A thorough workup disclosed platypnoea–orthodeoxia syndrome (POS) associated with right-to-left shunting through a patent foramen ovale (PFO). Percutaneous closure of the PFO was performed. After treatment, the patient’s arterial oxygen saturation gradually recovered to 98% on room air while she was in the sitting position and her symptoms disappeared. Reviewing this case retrospectively, we determined that the deviation of the spine with kyphosis progression had apparently proceeded as POS worsened over time. We therefore hypothesised that kyphosis progression had played a major role in the POS progression.


Annals of Vascular Diseases | 2018

Treatment Outcomes of Anticoagulant Therapy and Temporary Inferior Vena Cava Filter Implantation for Pregnancy Complicated by Venous Thrombosis

Takamichi Miyamoto; Junji Yamaguchi; Takamasa Iwai; Sadahiro Hijikata; Keita Watanabe; Yuichiro Sagawa; Ryo Masuda; Ryoichi Miyazaki; Naoyuki Miwa; Masahiro Sekigawa; Tetsuo Yamaguchi; Yasutoshi Nagata; Toshihiro Nozato; Orie Kobayashi; Satoshi Umezawa; Toru Obayashi

Objective: Although deep vein thrombosis (DVT) followed by pulmonary thromboembolism (PE) is a critical complication during pregnancy, there have been few reports about its intrapartum management. We evaluated intrapartum management by using a temporary inferior vena cava filter (IVCF) in pregnant women with PE/DVT. Materials and Methods: Eleven women with PE/DVT during pregnancy between January 2004 and December 2016 were included. The patients were hospitalized for intravenous unfractionated heparin infusion after acute PE/DVT onset. Seven patients were discharged and continued treatment with subcutaneous injection of heparin at the outpatient unit. IVCF was implanted 1–3 days before delivery in 10 patients. Anticoagulant therapy was discontinued 6–12 h before delivery. We retrospectively analyzed rates of maternal or perinatal death, and recurrence of symptomatic PE/DVT. Results: One patient was diagnosed as having PE/DVT and 10 had DVT alone. One patient suffered hemorrhagic shock during delivery; however, maternal or perinatal death and recurrence of symptomatic PE/DVT did not occur in any patient. Conclusion: Maternal or perinatal death and recurrence of symptomatic PE/DVT was not seen in women diagnosed as having PE/DVT during pregnancy and treated with anticoagulant therapy and IVCF.


Cardiovascular Pathology | 2017

Recurrent pulmonary emboli with characteristic histopathology

Sadahiro Hijikata; Takamichi Miyamoto; Junji Yamaguchi; Takamasa Iwai; Keita Watanabe; Yuichiro Sagawa; Ryo Masuda; Ryoichi Miyazaki; Naoyuki Miwa; Masahiro Sekigawa; Tetsuo Yamaguchi; Yasutoshi Nagata; Toshihiro Nozato; Urara Sakurai; Kenzo Hirao

We report a unique case of recurrent thromboembolism and its histological findings that were revealed in an autopsy. Although it is well known that repeating thrombosis presents organization and recanalization, we also observed rare findings of thickening of the bronchial artery and fixation of the valve of the lower extremity vein in this case.


Annals of Vascular Diseases | 2017

Assessment of the Safety and Efficacy of Edoxaban for the Treatment of Venous Thromboembolism Secondary to Active Malignancy

Takamichi Miyamoto; Takamasa Iwai; Junji Yamaguchi; Sadahiro Hijikata; Keita Watanabe; Yuichiro Sagawa; Ryo Masuda; Ryoichi Miyazaki; Naoyuki Miwa; Masahiro Sekigawa; Tetsuo Yamaguchi; Yasutoshi Nagata; Toshihiro Nozato; Toru Obayashi

Objective: To assess the safety and efficacy of edoxaban for the treatment of venous thromboembolism (VTE) secondary to active malignancy. Materials and Methods: We enrolled 48 patients with newly diagnosed VTE secondary to active malignancy that was treated with oral edoxaban for 1 year between September 2014 and August 2015. We retrospectively examined the presence or absence of recurrent symptomatic VTE, VTE-related mortality, and bleeding events. Results: No recurrent symptomatic VTE or VTE-related deaths were recorded, enabling efficient assessment. Treatment safety was determined based on the reports of bleeding. Bleeding was reported in two patients, with serious bleeding in one of them. Conclusion: Edoxaban is safe and effective for the treatment of VTE secondary to active malignancy.


International Heart Journal | 2018

Early Transfer of Patients with Acute Heart Failure from a Core Hospital to Collaborating Hospitals and Their Prognoses

Tetsuo Yamaguchi; Takamichi Miyamoto; Masahiro Sekigawa; Keita Watanabe; Sadahiro Hijikata; Junji Yamaguchi; Takamasa Iwai; Yuichiro Sagawa; Ryoichi Miyazaki; Ryo Masuda; Naoyuki Miwa; Yasutoshi Nagata; Toru Obayashi; Toshihiro Nozato

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Toshihiro Nozato

Tokyo Medical and Dental University

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Yasutoshi Nagata

Memorial Hospital of South Bend

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Masahiro Sekigawa

Tokyo Medical and Dental University

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Kenzo Hirao

Tokyo Medical and Dental University

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Mitsuaki Isobe

Tokyo Medical and Dental University

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Yasuteru Yamauchi

Tokyo Medical and Dental University

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Atsuhiko Yagishita

Tokyo Medical and Dental University

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