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Dive into the research topics where Takeshi Ozaki is active.

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Featured researches published by Takeshi Ozaki.


Circulation-cardiovascular Imaging | 2009

Age- and Gender-Specific Changes in the Left Ventricular Relaxation A Doppler Echocardiographic Study in Healthy Individuals

Hiroyuki Okura; Yuko Takada; Azusa Yamabe; Tomoichiro Kubo; Koichiro Asawa; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Minoru Yoshiyama; Junichi Yoshikawa; Kiyoshi Yoshida

Background—Although left ventricular diastolic function has been shown to deteriorate with advancing age, its gender-specific change is unknown. The aim of this study was to investigate age- and gender-specific changes in tissue Doppler–derived left ventricular diastolic index, E′. Methods and Results—A total of 1333 healthy individual without known heart disease or hypertension (mean age, 55 years; range, 10 to 89) were enrolled and studied. Peak early mitral annular velocity (E′) and peak late mitral annular velocity (A′) were recorded and measured. As an index of the left ventricular relaxation, E′ was used. As an index of the left ventricular filling pressure, E/E′ was calculated. Although systolic indices poorly correlated with age, diastolic indices correlated well with age. Among those aged 30 to 39 and 40 to 49 years, E′ was significantly lower in males than in females. In subjects aged 50 to 59 and 60 to 69 years, E′ was similar in both genders. Among those aged 70 to 79 and 80 to 89 years, E′ was significantly lower in females than in males. Predictors of the lowest quartile of E′ among subjects aged >50 years were age (P<0.0001; &khgr;2=66.11; odds ratio, 1.08; 95% CI, 1.058 to 1.097) and female gender (P=0.002; &khgr;2=9.23; odds ratio, 1.68; 95% CI, 1.202 to 2.343). Conclusion—Age-related changes in diastolic indices were gender specific. In the elderly population, diastolic function deteriorated more significantly in the female gender than in the male gender. These results may explain the relatively higher incidence in elderly females among patients with diastolic heart failure and higher cardiovascular mortality in the female gender.Background— Although left ventricular diastolic function has been shown to deteriorate with advancing age, its gender-specific change is unknown. The aim of this study was to investigate age- and gender-specific changes in tissue Doppler–derived left ventricular diastolic index, E′. Methods and Results— A total of 1333 healthy individual without known heart disease or hypertension (mean age, 55 years; range, 10 to 89) were enrolled and studied. Peak early mitral annular velocity (E′) and peak late mitral annular velocity (A′) were recorded and measured. As an index of the left ventricular relaxation, E′ was used. As an index of the left ventricular filling pressure, E/E′ was calculated. Although systolic indices poorly correlated with age, diastolic indices correlated well with age. Among those aged 30 to 39 and 40 to 49 years, E′ was significantly lower in males than in females. In subjects aged 50 to 59 and 60 to 69 years, E′ was similar in both genders. Among those aged 70 to 79 and 80 to 89 years, E′ was significantly lower in females than in males. Predictors of the lowest quartile of E′ among subjects aged >50 years were age ( P <0.0001; χ2=66.11; odds ratio, 1.08; 95% CI, 1.058 to 1.097) and female gender ( P =0.002; χ2=9.23; odds ratio, 1.68; 95% CI, 1.202 to 2.343). Conclusion— Age-related changes in diastolic indices were gender specific. In the elderly population, diastolic function deteriorated more significantly in the female gender than in the male gender. These results may explain the relatively higher incidence in elderly females among patients with diastolic heart failure and higher cardiovascular mortality in the female gender. Received July 22, 2008; accepted October 30, 2008. # CLINICAL PERSPECTIVE {#article-title-2}


Journal of the American College of Cardiology | 2010

TARGET LESION THIN-CAP FIBROATHEROMA DETECTED BY VIRTUAL HISTOLOGY INTRAVASCULAR ULTRASOUND AND LONG-TERM PROGNOSIS IN PATIENTS WITH ANGINA PECTORIS

Hiroyuki Okura; Takahiro Kawamoto; Ryotaro Yamada; Yoshinori Miyamoto; Tetsuo Tsuchiya; Akihiro Hayashida; Yoji Neishi; Tomoichiro Kubo; Nobuya Matsushita; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Kiyoshi Yoshida

Background: Radiofrequency signal derived tissue characterization of intravascular ultrasound (IVUS) has become clinically available. Several reports suggested that virtual histology (VH)-IVUS lesion assessments could predict distal microembolization and microvascular injury during percutaneous coronary intervention (PCI). The aim of this study was to investigate whether pre-PCI lesion assessment (presence or absence of thincap fibroatheroma, TCFA) by VH-IVUS predicts long-term clinical outcome in patients with angina pectoris.


Circulation-cardiovascular Imaging | 2009

Age- and Gender-Specific Changes in the Left Ventricular RelaxationCLINICAL PERSPECTIVE

Hiroyuki Okura; Yuko Takada; Azusa Yamabe; Tomoichiro Kubo; Koichiro Asawa; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Minoru Yoshiyama; Junichi Yoshikawa; Kiyoshi Yoshida

Background—Although left ventricular diastolic function has been shown to deteriorate with advancing age, its gender-specific change is unknown. The aim of this study was to investigate age- and gender-specific changes in tissue Doppler–derived left ventricular diastolic index, E′. Methods and Results—A total of 1333 healthy individual without known heart disease or hypertension (mean age, 55 years; range, 10 to 89) were enrolled and studied. Peak early mitral annular velocity (E′) and peak late mitral annular velocity (A′) were recorded and measured. As an index of the left ventricular relaxation, E′ was used. As an index of the left ventricular filling pressure, E/E′ was calculated. Although systolic indices poorly correlated with age, diastolic indices correlated well with age. Among those aged 30 to 39 and 40 to 49 years, E′ was significantly lower in males than in females. In subjects aged 50 to 59 and 60 to 69 years, E′ was similar in both genders. Among those aged 70 to 79 and 80 to 89 years, E′ was significantly lower in females than in males. Predictors of the lowest quartile of E′ among subjects aged >50 years were age (P<0.0001; &khgr;2=66.11; odds ratio, 1.08; 95% CI, 1.058 to 1.097) and female gender (P=0.002; &khgr;2=9.23; odds ratio, 1.68; 95% CI, 1.202 to 2.343). Conclusion—Age-related changes in diastolic indices were gender specific. In the elderly population, diastolic function deteriorated more significantly in the female gender than in the male gender. These results may explain the relatively higher incidence in elderly females among patients with diastolic heart failure and higher cardiovascular mortality in the female gender.Background— Although left ventricular diastolic function has been shown to deteriorate with advancing age, its gender-specific change is unknown. The aim of this study was to investigate age- and gender-specific changes in tissue Doppler–derived left ventricular diastolic index, E′. Methods and Results— A total of 1333 healthy individual without known heart disease or hypertension (mean age, 55 years; range, 10 to 89) were enrolled and studied. Peak early mitral annular velocity (E′) and peak late mitral annular velocity (A′) were recorded and measured. As an index of the left ventricular relaxation, E′ was used. As an index of the left ventricular filling pressure, E/E′ was calculated. Although systolic indices poorly correlated with age, diastolic indices correlated well with age. Among those aged 30 to 39 and 40 to 49 years, E′ was significantly lower in males than in females. In subjects aged 50 to 59 and 60 to 69 years, E′ was similar in both genders. Among those aged 70 to 79 and 80 to 89 years, E′ was significantly lower in females than in males. Predictors of the lowest quartile of E′ among subjects aged >50 years were age ( P <0.0001; χ2=66.11; odds ratio, 1.08; 95% CI, 1.058 to 1.097) and female gender ( P =0.002; χ2=9.23; odds ratio, 1.68; 95% CI, 1.202 to 2.343). Conclusion— Age-related changes in diastolic indices were gender specific. In the elderly population, diastolic function deteriorated more significantly in the female gender than in the male gender. These results may explain the relatively higher incidence in elderly females among patients with diastolic heart failure and higher cardiovascular mortality in the female gender. Received July 22, 2008; accepted October 30, 2008. # CLINICAL PERSPECTIVE {#article-title-2}


Circulation-cardiovascular Imaging | 2009

Age- and Gender-Specific Changes in the Left Ventricular RelaxationCLINICAL PERSPECTIVE: A Doppler Echocardiographic Study in Healthy Individuals

Hiroyuki Okura; Yuko Takada; Azusa Yamabe; Tomoichiro Kubo; Koichiro Asawa; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Minoru Yoshiyama; Junichi Yoshikawa; Kiyoshi Yoshida

Background—Although left ventricular diastolic function has been shown to deteriorate with advancing age, its gender-specific change is unknown. The aim of this study was to investigate age- and gender-specific changes in tissue Doppler–derived left ventricular diastolic index, E′. Methods and Results—A total of 1333 healthy individual without known heart disease or hypertension (mean age, 55 years; range, 10 to 89) were enrolled and studied. Peak early mitral annular velocity (E′) and peak late mitral annular velocity (A′) were recorded and measured. As an index of the left ventricular relaxation, E′ was used. As an index of the left ventricular filling pressure, E/E′ was calculated. Although systolic indices poorly correlated with age, diastolic indices correlated well with age. Among those aged 30 to 39 and 40 to 49 years, E′ was significantly lower in males than in females. In subjects aged 50 to 59 and 60 to 69 years, E′ was similar in both genders. Among those aged 70 to 79 and 80 to 89 years, E′ was significantly lower in females than in males. Predictors of the lowest quartile of E′ among subjects aged >50 years were age (P<0.0001; &khgr;2=66.11; odds ratio, 1.08; 95% CI, 1.058 to 1.097) and female gender (P=0.002; &khgr;2=9.23; odds ratio, 1.68; 95% CI, 1.202 to 2.343). Conclusion—Age-related changes in diastolic indices were gender specific. In the elderly population, diastolic function deteriorated more significantly in the female gender than in the male gender. These results may explain the relatively higher incidence in elderly females among patients with diastolic heart failure and higher cardiovascular mortality in the female gender.Background— Although left ventricular diastolic function has been shown to deteriorate with advancing age, its gender-specific change is unknown. The aim of this study was to investigate age- and gender-specific changes in tissue Doppler–derived left ventricular diastolic index, E′. Methods and Results— A total of 1333 healthy individual without known heart disease or hypertension (mean age, 55 years; range, 10 to 89) were enrolled and studied. Peak early mitral annular velocity (E′) and peak late mitral annular velocity (A′) were recorded and measured. As an index of the left ventricular relaxation, E′ was used. As an index of the left ventricular filling pressure, E/E′ was calculated. Although systolic indices poorly correlated with age, diastolic indices correlated well with age. Among those aged 30 to 39 and 40 to 49 years, E′ was significantly lower in males than in females. In subjects aged 50 to 59 and 60 to 69 years, E′ was similar in both genders. Among those aged 70 to 79 and 80 to 89 years, E′ was significantly lower in females than in males. Predictors of the lowest quartile of E′ among subjects aged >50 years were age ( P <0.0001; χ2=66.11; odds ratio, 1.08; 95% CI, 1.058 to 1.097) and female gender ( P =0.002; χ2=9.23; odds ratio, 1.68; 95% CI, 1.202 to 2.343). Conclusion— Age-related changes in diastolic indices were gender specific. In the elderly population, diastolic function deteriorated more significantly in the female gender than in the male gender. These results may explain the relatively higher incidence in elderly females among patients with diastolic heart failure and higher cardiovascular mortality in the female gender. Received July 22, 2008; accepted October 30, 2008. # CLINICAL PERSPECTIVE {#article-title-2}


Circulation | 2011

Prevalence and Correlates of Physiological Valvular Regurgitation in Healthy Subjects

Hiroyuki Okura; Yuko Takada; Azusa Yamabe; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Minoru Yoshiyama; Junichi Yoshikawa; Kiyoshi Yoshida


Japanese Circulation Journal-english Edition | 2008

PJ-373 What is the predictor of in srent restenosis after implantation of sirolimus eluting stent ?(Restenosis basic/clinical(04)(IHD),Poster Session(Japanese),The 72nd Annual Scientific Meeting of the Japanese Circulation Society)

Hiroki Fukuda; Ryotaro Yamada; Haruyuki Taguchi; Hiroyuki Okura; Satoko Wada; Tomoichiro Kubo; Koichiro Asawa; Takeshi Ozaki; Iku Toda; Minoru Yoshiyama; Kiyoshi Yoshida


Circulation-cardiovascular Imaging | 2009

Age- and Gender-Specific Changes in the Left Ventricular Relaxation

Hiroyuki Okura; Yuko Takada; Azusa Yamabe; Tomoichiro Kubo; Koichiro Asawa; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Minoru Yoshiyama; Junichi Yoshikawa; Kiyoshi Yoshida


Japanese Circulation Journal-english Edition | 2011

Prevalence and Correlates of Physiological Valvular Regurgitation in Healthy Subjects : A Color Doppler Echocardiographic Study in the Current Era

Hiroyuki Okura; Yuko Takada; Azusa Yamabe; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Minoru Yoshiyama; Junichi Yoshikawa; Kiyoshi Yoshida


Journal of the American College of Cardiology | 2011

AGE AND GENDER AFFECT LEFT VENTRICULAR RELAXATION IN PATIENTS WITH MYOCARDIAL INFARCTION: A TISSUE DOPPLER ECHOCARDIOGRAPHY STUDY

Hiroyuki Okura; Ryugo Yamakawa; Noriko Toyoshima; Shogo Sakamoto; Yoko Morishita; Nobuya Mastushita; Kenji Shimeno; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Kiyoshi Yoshida


Journal of the American College of Cardiology | 2011

CULPRIT LESION REMODELING AND LONG-TERM MORTALITY IN PATIENTS WITH ACUTE CORONARY SYNDROME

Hiroyuki Okura; Nobuya Matsushita; Kenji Shimeno; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Kiyoshi Yoshida

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Iku Toda

Osaka City University

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Tomoichiro Kubo

Wakayama Medical University

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