ULTRASONIC INSTRUMENTATION FOR CARDIOVASCULAR STUDIES

我们的目标是开发和利用几种超声波技术 急性心肌梗死患者的血流、血压和心脏内径的测量 心血管疾病和患者的慢性仪器化动物模型 正在接受冠状动脉搭桥手术。具体项目有：1) 评价血流动力学(速度曲线、速度波形 大隐静脉搭桥术(SVBP)的研制和压力波形的研制 先前使用20 MHz脉冲多普勒多谱勒的MAN移植物 已开发和待开发的血管外眼压计，2)使用 血流动力学信息，开发和评价一种简单易用的超声波 带廉价、隔离探头的流量计，用于S-V-BP移植，3) 在动物身上开发和评估脉冲回波/多普勒技术(10和/或20 MHZ)评价局部左心功能(通过室壁增厚) 分离心内膜和心外膜动力学的能力，4)发展和 无创真空附着式换能器在动物体内的评价 上面的功能测量以及区域冠脉血流检测 20 MHz脉冲多普勒仪，5)利用脉冲多谱勒测速 动脉和静脉微血管吻合时的波形和面积缩小 在重建手术过程中，和6)发展一个完整的 超声测量系统在手术中的最终应用 使用无创技术并能够测量血流速度的患者 通过天然冠状动脉，血流量通过几个旁路 移植物，每个移植物的高保真压力和心脏功能 左心室多个部位的心外膜和心内膜。

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.