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Publication
Featured researches published by Takeshi Ozaki.
Circulation-cardiovascular Imaging | 2009
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
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
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
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
Hiroyuki Okura; Yuko Takada; Azusa Yamabe; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Minoru Yoshiyama; Junichi Yoshikawa; Kiyoshi Yoshida
Japanese Circulation Journal-english Edition | 2008
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
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
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
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
Hiroyuki Okura; Nobuya Matsushita; Kenji Shimeno; Takeshi Ozaki; Hiroyuki Yamagishi; Iku Toda; Kiyoshi Yoshida