Onset of pulsatile waves in the heart walls at end-systole

We have previously developed a novel ultrasonic method, namely, the phased tracking method, for accurately tracking the movement of the heart wall bas ed on both the phase and magnitude of the demodulated signals to determine the instantaneous position of an object. With this method, it is possible t o accurately detect small-amplitude velocity signals of less than a few mic rometers of the heart wall that are superimposed on the motion of the heart wall due to the heart beat. There are several remarkable pulsatile waves d uring one cardiac cycle in the resultant velocity signals, some of them bei ng commonly obtained for both healthy subjects and patients. These pulsatil e waves cannot be recognized in standard echocardiography M-mode images. In this paper, by focusing on one pulsatile wave that occurs around the end-s ystole, the physiological meaning of these is considered based on various i n-vivo experiments. The pulsatile wave measured by this novel ultrasonic me thod will offer potential for a quantitative assessment of myocardial viabi lity. (C) 2000 Elsevier Science B.V. All rights reserved.