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Dive into the research topics where Yoichi Takaya is active.

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Featured researches published by Yoichi Takaya.


Circulation | 2015

Risk Stratification of Acute Kidney Injury Using the Blood Urea Nitrogen/Creatinine Ratio in Patients With Acute Decompensated Heart Failure

Yoichi Takaya; Fumiki Yoshihara; Hiroyuki Yokoyama; Hideaki Kanzaki; Masafumi Kitakaze; Yoichi Goto; Toshihisa Anzai; Satoshi Yasuda; Hisao Ogawa; Yuhei Kawano

BACKGROUND Risk stratification of acute kidney injury (AKI) is important for acute decompensated heart failure (ADHF). The aim of this study was to determine whether clinical markers, such as the blood urea nitrogen/creatinine ratio (BUN/Cr) or BUN or creatinine values alone, stratify the risk of AKI for mortality. METHODS AND RESULTS In all, 371 consecutive ADHF patients were enrolled in the study. AKI was defined as serum creatinine ≥0.3 mg/dl or a 1.5-fold increase in serum creatinine levels within 48 h. During ADHF therapy, AKI occurred in 99 patients; 55 patients died during the 12-month follow-up period. Grouping patients according to AKI and a median BUN/Cr at admission of 22.1 (non-AKI+low BUN/Cr, non-AKI+high BUN/Cr, AKI+low BUN/Cr, and AKI+high BUN/Cr groups) revealed higher mortality in the AKI+high BUN/Cr group (log-rank test, P<0.001). Coxs proportional hazard analysis revealed an association between AKI+high BUN/Cr and mortality, whereas the association with AKI+low BUN/Cr did not reach statistical significance. When patients were grouped according to AKI and median BUN or creatinine values at admission, AKI was associated with mortality, regardless of BUN or creatinine. CONCLUSIONS The combination of AKI and elevated BUN/Cr, but not BUN or creatinine individually, is linked with an increased risk of mortality in ADHF patients, suggesting that the BUN/Cr is useful for risk stratification of AKI.


Heart and Vessels | 2013

Evaluation of exercise capacity using wave intensity in chronic heart failure with normal ejection fraction

Yoichi Takaya; Manabu Taniguchi; Motoaki Sugawara; Saori Nobusada; Kengo Kusano; Teiji Akagi; Hiroshi Ito

Impaired exercise capacity has been found in patients with diastolic dysfunction with preserved systolic function. Although conventional transthoracic echocardiography (TTE) provides useful clinical information about systolic and diastolic cardiac function, its capability to evaluate exercise capacity has been controversial. The inertia force of late systolic aortic flow is known to have a tight relationship with left ventricular (LV) performance during the period from near end-systole to isovolumic relaxation. The inertia force and the time constant of LV pressure decay during isovolumic relaxation can be estimated noninvasively using the second peak (W2) of wave intensity (WI), which is measured with an echo-Doppler system. We sought to determine whether W2 is associated with exercise capacity in patients with chronic heart failure with normal ejection fraction (HFNEF) and to compare its ability to predict exercise capacity with parameters obtained by conventional TTE including tissue Doppler imaging. Sixteen consecutive patients with chronic HFNEF were enrolled in this study. Wave intensity was obtained with a color Doppler system for measurement of blood velocity combined with an echo-tracking system for detecting changes in vessel diameter. Concerning conventional TTE, we measured LV ejection fraction (EF), peak velocities of early (E) and late (A) mitral inflow using pulse-wave Doppler, and early (Ea) and late (Aa) diastolic velocities using tissue Doppler imaging. Left ventricular EF, E/A ratio, Ea, and E/Ea ratio did not correlate with exercise capacity, whereas W2 significantly correlated with peak VO2 (r = 0.54, p = 0.03), VE/VCO2 slope (r = −0.53, p = 0.03), and ΔVO2/ΔWR (r = 0.56, p = 0.02). W2 was associated with exercise capacity in patients with chronic HFNEF. In conclusion, W2 is considered to be clinically more useful than conventional TTE indices for evaluating exercise capacity in patients with chronic HFNEF.


Jacc-cardiovascular Interventions | 2015

Long-Term Outcome After Transcatheter Closure of Atrial Septal Defect in Older Patients Impact of Age at Procedure

Yoichi Takaya; Teiji Akagi; Yasufumi Kijima; Koji Nakagawa; Shunji Sano; Hiroshi Ito

OBJECTIVES This study assessed long-term outcome after transcatheter atrial septal defect (ASD) closure in older patients, especially those older than 75 years of age. BACKGROUND The clinical benefits of transcatheter ASD closure in this aged population are controversial. METHODS A total of 244 patients older than 50 years of age were divided into 3 groups according to age at procedure (50 to 59 years: n=69; 60 to 74 years: n=120; 75 years and older: n=55). The primary endpoint was defined as all-cause mortality and hospitalization due to heart failure or stroke. Improvements in functional capacity and cardiac remodeling after the procedure were also assessed. RESULTS During a median follow-up of 36 months, mortality and hospitalization due to heart failure or stroke occurred in 18 patients (7%). Among patients older than 75 years of age, 2 died of noncardiovascular disease, 2 were hospitalized due to heart failure, and 1 had a stroke. More than 90% of patients older than 75 years of age did not experience these events. Kaplan-Meier analysis showed that the event-free survival rate was not different among the 3 age groups (log-rank test, p=0.780). New York Heart Association functional class and right ventricular/left ventricular end-diastolic diameter ratio improved in patients older than 75 years of age, similar to the other age groups. CONCLUSIONS Long-term outcome after transcatheter ASD closure in patients older than 75 years of age is similar to that in the other, relatively younger age groups. This suggests that transcatheter ASD closure can be considered a valuable therapeutic option in patients older than 75 years of age.


American Journal of Cardiology | 2015

Outcomes in Patients With High-Degree Atrioventricular Block as the Initial Manifestation of Cardiac Sarcoidosis

Yoichi Takaya; Kengo Kusano; Kazufumi Nakamura; Hiroshi Ito

Although high-degree atrioventricular block (AVB) is a common initial manifestation of cardiac sarcoidosis, little is known about the outcomes. The aim of this study was to assess outcomes in patients with AVB as an initial manifestation of cardiac sarcoidosis compared with those in patients with ventricular tachyarrhythmia (VT) and/or heart failure (HF). Fifty-three consecutive patients with cardiac sarcoidosis, who had high-degree AVB (n = 22) or VT and/or HF (n = 31), were enrolled. The end point was defined as major adverse cardiac events, including cardiac death, ventricular fibrillation, sustained VT, and hospitalization for HF. Over a median follow-up period of 34 months, the outcomes of major adverse cardiac events were better in patients with high-degree AVB than in those with VT and/or HF (log-rank test, p = 0.046). However, this difference was due mainly to HF hospitalization. The outcomes of fatal cardiac events, including cardiac death, ventricular fibrillation, and sustained VT, were comparable between the 2 groups (log-rank test, p = 0.877). The fatal cardiac events in patients with high-degree AVB were not associated with the initiation of steroid treatment or left ventricular dysfunction. In conclusion, the outcomes of major adverse cardiac events are better in patients with high-degree AVB than in those with VT and/or HF. However, patients with high-degree AVB have a high rate of fatal cardiac events, similar to those with VT and/or HF. An indication for an implantable cardioverter-defibrillator, but not a pacemaker system, can be considered in patients with cardiac sarcoidosis manifested by high-degree AVB.


Cardiovascular Intervention and Therapeutics | 2014

Transcatheter closure of right-to-left atrial shunt in patients with platypnea-orthodeoxia syndrome associated with aortic elongation

Yoichi Takaya; Teiji Akagi; Yasufumi Kijima; Koji Nakagawa; Manabu Taniguchi; Hayato Ohtani; Shunji Sano; Hiroshi Ito

Platypnea-orthodeoxia is a rare condition characterized by dyspnea and oxygen desaturation induced by the upright position and relieved by recumbency. The most common cause of this syndrome is right-to-left shunt through interatrial communications such as patent foramen ovale (PFO) or atrial septal defect (ASD). In addition, this syndrome can be caused by other extracardiac components, including pulmonary emphysema, pericardial disease, and prominent Eustachian valve. We experienced 3 cases of this syndrome, including 1 patient with PFO and 2 patients with ASD. Computer tomography imaging revealed aortic elongation and compression of the right atrium by ascending aorta in all of 3 patients. Transcatheter closure of PFO or ASD was successfully performed in all patients, including immediate improvements of symptoms and oxygen saturation without any complications.


American Journal of Cardiology | 2015

Comparison of outcomes in patients with probable versus definite cardiac sarcoidosis

Yoichi Takaya; Kengo Kusano; Kazufumi Nakamura; Hiroshi Ito

Patients with probable cardiac sarcoidosis (CS) who satisfy only clinical cardiac findings for CS are not uncommon. The aim of this study was to compare outcomes between patients with probable CS and those with definite CS treated with steroids. The study population consisted of 101 consecutive patients who satisfied clinical cardiac findings for CS. Patients with definite CS were defined as having histologic or clinical confirmation of CS according to the guidelines and were treated with steroids. Patients with probable CS were defined as having only clinical cardiac findings but not definite CS because of no histologic confirmation or extracardiac sarcoidosis and were not treated with steroids. The end point was major adverse cardiac events. Forty-seven patients had definite CS, and the other 54 had probable CS. Except for serum angiotensin-converting enzyme levels and left ventricular dysfunction, clinical characteristics were similar between the 2 groups. Over a median follow-up period of 15 months, major adverse cardiac events occurred more frequently in patients with probable CS than in those with definite CS (74% vs 53%, p=0.029). The event-free survival rate was worse in patients with probable CS than in those with definite CS (log-rank test, p=0.006). Cox proportional-hazards analysis showed that probable CS was an independent predictor of major adverse cardiac events. In conclusion, outcomes were worse in patients with probable CS than in those with definite CS treated with steroids. The initiation of steroid treatment may be considered for patients who satisfy only clinical cardiac findings for CS.


Journal of Cardiovascular Computed Tomography | 2015

Comprehensive assessment of morphology and severity of atrial septal defects in adults by CT

Kazuhiro Osawa; Toru Miyoshi; Yusuke Morimitsu; Teiji Akagi; Hiroki Oe; Koji Nakagawa; Yoichi Takaya; Yasufumi Kijima; Shuhei Sato; Susumu Kanazawa; Hiroshi Ito

BACKGROUND Cardiac CT is an excellent tool for evaluating the anatomy of a secundum atrial septal defect (ASD). However, a comprehensive assessment of its usefulness, including measurement of the pulmonary to systemic blood flow ratio in secundum ASD patients, has not been performed. OBJECTIVE Therefore, this study was designed to evaluate the usefulness of CT for assessing the hemodynamics of secundum ASD in adults compared with transesophageal echocardiography (TEE), transthoracic echocardiography, and invasive catheterization. METHODS Fifty adult patients with secundum ASD were enrolled. Cardiac CT scans (128-slice multidetector CT instrument) were acquired. These were followed by 2-dimensional reconstruction of the secundum ASDs to determine the defect size, the rim length between the outer edge of the defect, and the pulmonary to systemic blood flow (Qp/Qs) ratio. RESULTS The maximum sizes of the secundum ASDs derived from CT and TEE studies were comparable (21.2 ± 8.0 vs. 20.0 ± 7.3 mm; P = .41; r = 0.960; P < .001). The rim lengths for the aortic, mitral, and tricuspid valves; the inferior vena cava; and posterior atrium were also comparable between CT and TEE measurements. The mean Qp/Qs ratio that was derived from CT measurements was comparable with that found by invasive catheterization (2.3 ± 0.7 vs. 2.3 ± 0.8; P = .73; r = 0.786; P < .001). CONCLUSION Cardiac CT is feasible for assessing pathology and the severity of secundum ASD in adults.


American Journal of Cardiology | 2015

Fate of Mitral Regurgitation after Transcatheter Closure of Atrial Septal Defect in Adults

Yoichi Takaya; Yasufumi Kijima; Teiji Akagi; Koji Nakagawa; Hiroki Oe; Manabu Taniguchi; Shunji Sano; Hiroshi Ito

Although the volume overload of pulmonary circulation improves after atrial septal defect (ASD) closure, the increasing left ventricular preload may contribute to mitral regurgitation (MR) deterioration. We aimed to evaluate the impact of MR after transcatheter ASD closure on clinical outcomes in adults. A total of 288 consecutive patients who underwent transcatheter ASD closure were enrolled. Changes in MR were assessed at 1 month after the procedure. The end point was defined as cardiovascular events. After the procedure, MR ameliorated in 3 patients and unchanged in 253, whereas MR deteriorated in 32. During a median follow-up of 24 months, patients with MR deterioration had no cardiovascular events, and the event-free survival rate was not different between patients with MR deterioration and those with MR amelioration or no-change (p = 0.355). Even in patients with MR deterioration, the New York Heart Association functional class improved after the procedure, with no cases of worsening functional class. Multivariate logistic regression analysis showed that MR deterioration was independently related to advanced age and female gender. The degree of enlargement of mitral valve annulus diameter after the procedure was greater in patients with MR deterioration than in those with MR amelioration or no-change, and it was correlated with the degree of MR deterioration. In conclusion, MR deterioration occurs in a minority of adult patients after transcatheter ASD closure; however, it is not linked with adverse outcomes. MR deterioration may be provoked by geometric changes in mitral valve annulus, especially in women with advanced age.


International Journal of Cardiology | 2017

Early and frequent defibrillator discharge in patients with cardiac sarcoidosis compared with patients with idiopathic dilated cardiomyopathy

Yoichi Takaya; Kengo Kusano; Nobuhiro Nishii; Kazufumi Nakamura; Hiroshi Ito

BACKGROUND Little is known about the suitability of implantable cardioverter defibrillator (ICD) implantation in patients with cardiac sarcoidosis (CS). We evaluated the efficacy of ICD implantation in patients with CS, including suspected CS, compared with those with idiopathic dilated cardiomyopathy (DCM). METHODS A total of 102 consecutive patients with definite CS, suspected CS, or DCM who underwent ICD implantation were enrolled. The endpoint was the first documentation of appropriate ICD therapy for ventricular tachyarrhythmias. The follow-up started after ICD implantation. RESULTS Appropriate ICD therapies occurred in 15 (56%) of 27 patients with definite CS, 17 (68%) of 25 with suspected CS, and 16 (32%) of 50 with DCM. The rate of appropriate ICD therapies was higher in patients with definite CS and those with suspected CS than in those with DCM (log-rank test, p=0.010). After ICD implantation, five or more appropriate ICD therapies occurred in 5 (19%) patients with definite CS and 10 (40%) with suspected CS, but in only 1 (2%) with DCM. Cox proportional hazard analysis showed that CS, including suspected CS, was independently associated with appropriate ICD therapies. For primary prevention, the rate of appropriate ICD therapies was higher in patients with CS than in those with DCM (log-rank test, p=0.034). More than half of patients with CS received appropriate ICD therapies. CONCLUSIONS Patients with CS receive appropriate ICD therapies for ventricular tachyarrhythmias at a higher rate, compared with those with DCM, suggesting that ICD implantation should be performed in patients with CS.


Cardiology in The Young | 2016

Transcatheter closure of atrial septal defect in a patient with absent inferior caval vein connection: a novel technique using a steerable guide catheter.

Yoichi Takaya; Teiji Akagi; Hiroshi Ito

An alternative approach for transcatheter closure of atrial septal defect is necessary in patients with absent inferior caval vein connection. In this report, we describe the successful transcatheter atrial septal defect closure via the transjugular approach using a steerable guide catheter.

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Hiroshi Ito

Fukushima Medical University

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