Hiroshi Kanai

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Noninvasive measurement of mechanical properties, such as elasticity, of the arterial wall, is useful for diagnosis of atherosclerosis. The elasticity of the arterial wall can be estimated by combining measurement of displacement of the arterial wall with that of blood pressure. In general, the displacement of the arterial wall is estimated from the phase(More)
  • Hiroshi Kanai
  • IEEE transactions on ultrasonics, ferroelectrics…
  • 2005
Though myocardial viscoelasticity is essential in the evaluation of heart diastolic properties, it has never been noninvasively measured in vivo. By the ultrasonic measurement of the myocardial motion, we have already found that some pulsive waves are spontaneously excited by aortic-valve closure (AVC) at end-systole (T0). These waves may serve as an ideal(More)
BACKGROUND Knowledge of the physical properties of atherosclerotic plaque is essential when evaluating its vulnerability in a clinical setting. Such knowledge, however, is still difficult to obtain with the various approaches developed to date. METHODS AND RESULTS This article describes a noninvasive method for evaluating the regional elasticity (the(More)
Echocardiography is a widely used modality for diagnosis of the heart. It enables observation of the shape of the heart and estimation of global heart function based on B-mode and M-mode imaging. Subsequently, methods for estimating myocardial strain and strain rate have been developed to evaluate regional heart function. Furthermore, it has recently been(More)
Noninvasive measurement of mechanical properties, such as elasticity, of the arterial wall, is useful for diagnosis of atherosclerosis. For assessment of mechanical properties, it is necessary to measure the deformation of the arterial wall. In this study, a modification of the previously proposed phased-tracking method was conducted to improve measurement(More)
Pulse wave velocity (PWV) is the propagation velocity of the pressure wave along the artery due to the heartbeat. The PWV becomes faster with progression of arteriosclerosis and, thus, can be used as a diagnostic index of arteriosclerosis. Measurement of PWV is known as a noninvasive approach for diagnosis of arteriosclerosis and is widely used in clinical(More)
High-frame-rate echocardiography using unfocused transmit beams and parallel receive beamforming is a promising method for evaluation of cardiac function, such as imaging of rapid propagation of vibration of the heart wall resulting from electrical stimulation of the myocardium. In this technique, high temporal resolution is realized at the expense of(More)
Using a heart ischemia/reperfusion model in rats, we recently demonstrated that 3-[2-[4-(3-chloro-2-methylphenyl)-1-piperazinyl]ethyl]-5,6-dimethoxy-1-(4-imidazolylmethyl)-1H-indazole dihydrochloride 3.5 hydrate (DY-9760e), a calmodulin inhibitor, is a cardioprotective drug. Here, we examined cardioprotective mechanisms of DY-9760e in hypertrophy and heart(More)