ULTRASONIC INSTRUMENTATION FOR CARDIOVASCULAR STUDIES

我们的目标是开发和利用几种超声技术， 测量急性和急性期的血流、压力和心脏尺寸， 心血管疾病的慢性仪器化动物模型和患者 接受冠状动脉搭桥手术 具体项目有：1） 血流动力学评价（速度曲线、速度波形 发展，和压力波形发展）的隐静脉旁路（SVBP） 移植在人利用多距离门20 MHz脉冲多普勒以前 开发和血管外眼压计开发，2）使用 血流动力学信息，开发和评价一种简单易用超声 用于S. V. B. P.移植物的带有廉价隔离探头的流量计，3） 在动物中开发和评估脉冲回波/多普勒技术（10和/或20 MHz）用于评价局部左心室功能（通过室壁增厚）， 分离心内膜和心外膜动力学能力，4）发展和 在动物中评价无创伤真空连接换能器的区域 上述功能测量以及还用于区域冠状动脉流量感测， 20 MHz脉冲多普勒; 5）利用脉冲多普勒评估流速 动脉和静脉微血管吻合时的波形和面积减少 在重建外科手术过程中，以及6）制定一个综合的 超声测量系统，用于最终的术中应用， 使用无创技术并能够测量血流速度的患者 通过自体冠状动脉，通过几个旁路的血流量 移植物，每个移植物中的高保真压力， 左心室的几个区域的心外膜和内膜。

Our objective is to develop, and utilize several ultrasonic techniques in the measurement of blood flow, pressure, and cardiac dimensions in acute and chronically instrumented animal models of cardiovascular disease and in patients undergoing coronary artery bypass surgery. The specific projects are: 1) The evaluation of the hemodynamics (velocity profiles, velocity waveform development, and pressure waveform development) of saphenous vein bypass (SVBP) grafts in man utilizing a multiple range gate 20 MHz pulsed Doppler previously developed and an extravascular tonometer to be developed, 2) using the hemodynamic information, develop and evaluate a simple to use ultrasonic flowmeter with inexpensive, isolated probes for use on S.V.B.P. grafts, 3) develop and evaluate in animals a pulsed echo/Doppler technique (10 and/or 20 MHz) for evaluating regional left ventricular funtion (via wall thickening) with the ability to separate endocardial and epicardial dynamics, 4) develop and evaluate in animals atraumatic vacuum attached transducers for the regional function measurements above and also for regional coronary flow sensing using the 20 MHz pulsed Doppler, 5) utilize the pulsed Doppler to evaluate velocity waveforms, and area reductions at arterial and venous microvascular anastamoses during reconstructive surgical procedures, and 6) develop an integrated ultrasonic measurement system for eventual intraoperative applications in patients using atraumatic techniques and capable of measuring blood velocity through native coronary arteries, volume blood flow through several bypass grafts, high fidelity pressure in each graft, and myocardial function in the epicardium and endocardium of several regions of the left ventricle.