ULTRASONIC INSTRUMENTATION FOR CARDIOVASCULAR STUDIES

该项目的目标是开发、评估和利用几个 超声技术在测量血流、心功能 和力学，以及急性和慢性 心血管疾病的仪器动物模型，在患者中， 诊断和治疗冠状动脉疾病， 进行微血管重建 具体项目有：1） 继续发展单晶多普勒位移 通过增加距离门测量心肌增厚的技术 跟踪器可以跟踪任何想要的层。 这和原来的非跟踪 将使用导丝根据渡越时间方法评价器械， 海绵靶向体外和正常和缺血心肌， 长期使用仪器的狗 2)利用多普勒位移 仪器，以确定在跨壁的区域变化 正常和缺血心肌增厚的分布， 动物和患者在心脏手术期间。 3)轻松开发 可移动脉冲多普勒探头监测重建血管的通畅性 术后微血管修复。 4)开发一个小的，高的 使用高频（10或20 MHz）的分辨率血管直径传感器 渡越时间晶体或高频（20 MHz）多普勒位移 正在进行的血管舒缩研究中使用的探针，影响因素 动脉生长，静脉移植物的动脉化，以及对 血管扩张剂 5)开发一个微型（1毫米），单晶脉冲回波 导管从动脉壁内感测动脉壁厚度（和成分） 用于计划和评估球囊和激光扩张的血管 血管成形术。 6)开发一个微型（1 mm）20 MHz脉冲 具有用于感测流速的导丝腔的多普勒导管 在冠状动脉造影期间， 动脉造影和血管成形术。 应用包括 血管储备（充血反应）评估通过离散 在诊断过程中的病变和评价的影响， 血管成形术对血流和血管储备的影响。

The goal of this project is to develop, evaluate, and utilize several ultrasonic techniques in the measurement of blood flow, cardiac function and mechanics, and vascular dimensions in acute and chronically instrumented animal models of cardiovascular disease, in patients being diagnosed and treated for coronary artery disease, and in patients undergoing microvascular reconstruction. The specific projects are: 1) Continue the development of the single crystal Doppler displacement technique for measuring myocardial thickening by adding a range gate tracker to follow any desired layer. This and the original non-tracking device will be evaluated against the transit-time method using wire and sponge targets in-vitro and in normal and ischemic myocardium in acute and chronically instrumented dogs. 2) Utilize the Doppler displacement instrument to determine the regional variations in the transmural distribution of thickening in normal and ischemic myocardium both in animals and in patients during cardiac surgery. 3) Develop an easily removable pulsed Doppler probe to monitor the patency of reconstructive microvascular repairs post-operatively. 4) Develop a small, high resolution vessel diameter sensor using high frequency (10 or 20 MHz) transit-time crystals or a high frequency (20 MHz) Doppler displacement probe to be utilized in ongoing studies of vasomotion, factors affecting arterial growth, arteriolization of vein grafts, and regional responses to vasodilators. 5) Develop a miniature (1 mm), single-crystal pulse-echo catheter to sense arterial wall thickness (and composition) from within the vessel to be used to plan and assess dilatation with balloon and laser angioplasty procedures. 6) Develop a miniature (1 mm) 20 MHz pulsed Doppler catheter with a guide wire lumen for sensing flow velocity subselectively in the coronary arteries of man during coronary arteriography and angioplasty procedures. Applications include the assessment of vascular reserve (hyperemic response) through discrete lesions during diagnostic procedures and the evaluation of the effects of angioplasty on flow and vascular reserve.