Kazunori Yasuda
Ehime University
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Publication
Featured researches published by Kazunori Yasuda.
American Journal of Cardiology | 2017
Fumiyasu Seike; Teruyoshi Uetani; Kazuhisa Nishimura; Hiroshi Kawakami; Haruhiko Higashi; Jun Aono; Takayuki Nagai; Katsuji Inoue; Jun Suzuki; Hideo Kawakami; Takafumi Okura; Kazunori Yasuda; Jitsuo Higaki; Shuntaro Ikeda
Fractional flow reserve (FFR) is widely used for the assessment of myocardial ischemia. Optical coherence tomography (OCT) provides accurate visualization of coronary artery morphology. The aim of this study was to investigate the relation between FFR and OCT-derived FFR. We retrospectively analyzed 31 lesions (25 left anterior descending arteries, 2 left circumflex arteries, and 4 right coronary arteries) in 31 patients with moderate-to-severe coronary stenosis, who underwent OCT and FFR measurements simultaneously. OCT-derived FFR was calculated by the original algorithm, which was calculated using the following equation based on fluid dynamics: ΔP = FV + SV2, where V is the flow velocity, F is the coefficient of pressure loss because of viscous friction (Poiseuille resistance), and S is the coefficient of local pressure loss because of abrupt enhancement (flow separation). Mean values of % diameter stenosis by quantitative coronary angiography and FFR were 55.2 ± 14.0% and 0.70 ± 0.14, respectively. OCT-derived FFR showed a stronger linear correlation with FFR measurements (r = 0.89, p <0.001; root mean square error = 0.062 FFR units) than quantitative coronary angiography % diameter stenosis (r = -0.65, p <0.001), OCT measurements of minimum lumen area (r = 0.68, p <0.001), and % area stenosis (r = -0.70, p <0.001). OCT-derived FFR has the potential to become an alternative method for the assessment of functional myocardial ischemia, and may elucidate the relation between coronary morphology and FFR.
Circulation | 2018
Fumiyasu Seike; Teruyoshi Uetani; Kazuhisa Nishimura; Hiroshi Kawakami; Haruhiko Higashi; Akira Fujii; Jun Aono; Takayuki Nagai; Katsuji Inoue; Jun Suzuki; Shinji Inaba; Takafumi Okura; Kazunori Yasuda; Jitsuo Higaki; Shuntaro Ikeda
BACKGROUND Fractional flow reserve (FFR) is widely used for the assessment of myocardial ischemia. Intravascular ultrasound (IVUS) is an intracoronary imaging method that provides information about lumen and vessel morphology. Previous studies on the expanded use of IVUS to identify functional ischemia have noted an association between anatomy and physiology, but IVUS-derived minimum lumen area (MLA) has a weak-moderate correlation with myocardial ischemia compared with FFR. We developed a method to calculate FFR using IVUS-derived anatomical information for the assessment of myocardial ischemia. The aims of this study were to investigate the relationship between wire-based FFR and IVUS-derived FFR (IVUS-FFR) and to compare the usefulness of IVUS-FFR and IVUS-derived MLA for functional assessment.Methods and Results:We retrospectively analyzed 50 lesions in 48 patients with coronary stenosis who underwent IVUS and FFR simultaneously. IVUS-FFR was calculated using our original algorithm and fluid dynamics. Mean percent diameter stenosis determined on quantitative coronary angiography and on FFR was 56.4±10.7 and 0.69±0.08, respectively. IVUS-FFR had a stronger linear correlation with FFR (R=0.78, P<0.001; root mean square error, 0.057 FFR units) than with IVUS-derived MLA (R=0.43, P=0.002). CONCLUSIONS IVUS-FFR may be a more valuable method to identify myocardial ischemia, compared with IVUS-derived MLA.
American Journal of Cardiology | 2016
Fumiyasu Seike; Teruyoshi Uetani; Kazuhisa Nishimura; Chiharuko Iio; Hiroshi Kawakami; Kaori Fujimoto; Haruhiko Higashi; Tamami Kono; Jun Aono; Takayuki Nagai; Katsuji Inoue; Jun Suzuki; Akiyoshi Ogimoto; Takafumi Okura; Kazunori Yasuda; Jitsuo Higaki; Shuntaro Ikeda
International Journal of Fluid Machinery and Systems | 2017
Yukiharu Iwamoto; Ryo Kusuzaki; Motosuke Sogo; Kazunori Yasuda; Hidemasa Yamano; Masaaki Tanaka
Circulation | 2017
Fumiyasu Seike; Teruyoshi Uetani; Kazuhisa Nishimura; Hiroshi Kawakami; Haruhiko Higashi; Akira Fujii; Jun Aono; Takayuki Nagai; Katsuji Inoue; Jun Suzuki; Takafumi Okura; Kazunori Yasuda; Jitsuo Higaki; Shuntaro Ikeda
The Proceedings of Conference of Chugoku-Shikoku Branch | 2016
Katsuhiro Ando; Kazunori Yasuda; Yukiharu Iwamoto; Motosuke Sogo
The Proceedings of Conference of Chugoku-Shikoku Branch | 2016
Yoshihiko Teshima; Kazunori Yasuda; Yukiharu Iwamoto; Motosuke Sogo
The Proceedings of Conference of Chugoku-Shikoku Branch | 2016
Takafumi Uchiyama; Kazunori Yasuda; Yukiharu Iwamoto; Motosuke Sogo
The Proceedings of Conference of Chugoku-Shikoku Branch | 2016
Hiroyuki Oyama; Kazunori Yasuda; Yukiharu Iwamoto; Motosuke Sogo
Nihon Reoroji Gakkaishi | 2016
Taisuke Sato; Takatsune Narumi; Kazunori Yasuda; Akiomi Ushida; Ryuichi Kayaba