Simultanous Measurement of Velocity Signals at Multiple Points in the Heart Wall for Noninvasive Evaluation of Left Ventricular Inner Pressure and Elastic Modulus

心肌运动表现出高达100赫兹的频率成分，发现由相跟踪方法。为了同时测量左心室表面沿着多点快速、微小的速度信号，对传统超声诊断设备进行了改造，使其能在真实的时间内任意选择10条扇形扫描线进行分析。通过考虑心壁中速度的最大值和距胸部表面的最大深度，应仔细确定超声脉冲的传输方向的数量为10，以避免混叠，这比常规组织多普勒成像（TDI）中采用的数量少得多。应用该系统对3名健康志愿者心壁约240个点的速度信号进行了同步测量。在近终末期35ms的短时间内，心壁内的速度信号在空间上发生变化。在系统结束时 ...更多信息 即在室间隔基部附近的小波中，慢脉冲持续约30ms，刚好在第二心音辐射定时之前。然后，就在主动脉瓣关闭的时候出现了一个陡峭的脉搏。底部的陡脉冲比顶点的陡脉冲早几毫秒。通过对每个子波进行傅里叶变换，可以清晰地显示出陡脉冲分量相位的空间分布。通过对两例主动脉瓣狭窄（AS）患者的测量，可以直接检测到射血期的不规则振动信号，即对应于心音杂音的不规则振动信号。在常规TDI中，仅显示由于心跳引起的大的缓慢运动，而不能显示这些快速和微小的速度分量。此外，在本研究中，首次从沿沿着10条扫描线在多个点同时测量的每个速度信号中检测相位分量。这种测量和分析方法为心功能不全的新诊断技术提供了可能。少

Myocardial motion exhibits frequency components of up to 100 Hertz as found by a phased tracking method. To simultaneously measure the rapid and minute velocity signals at multiple points along the surface of the left ventricle (LV), in this study, conventional ultrasonic diagnosis equipment was modified to allow 10 scan lines from a sector scanner to be arbitrarily selected in real time for analysis. By considering the maximum value of the velocity in the heart wall and the maximum depth from the chest surface, the number of transmission directions of the ultrasonic pulses should be carefully confirmed to be 10 to avoid aliasing, which is much less than the number employed in conventional tissue Doppler imaging (TDI). By applying the system, the velocity signals at about 240 points in the heart walls were simultaneously measured for three healthy volunteers. During a short period of 35 ms around end-diastole, the velocity signals varied spatially in the heart wall. At the end of systo … More le, in the wavelets near the base of the interventricular septum (IVS), the slow pulse continued for about 30 ms just before the radiation timing of the second heart sound. Then, a steep pulse occurred just at the timing of the closure of the aortic valve. The steep pulse at the base preceded that at the apex by several milliseconds. By Fourier transforming each wavelet, the spatial distribution of the phase of the steep pulsive components were clearly displayed. By applying the measurement method to two patients with aortic stenosis (AS) , irregular vibration signals, which correspond to the murmur of the heart sound, could be directly detected during ejection period. In conventional TDI, only the large slow movements due to the heartbeat are displayed, while these rapid and minute velocity components cannot be displayed. In this study, moreover, the phase components were detected for the first time from each of the velocity signals simultaneously measured at multiple points along the 10 scan lines. This measurement and method of analysis offer potential for new diagnostic techniques in cardiac dysfunction. Less