CARDIOVASCULAR FLOW DYNAMICS--IN VIVO STUDIES

今年在这一项目上的努力继续研究 频谱和二维彩色心腔内血流动力学 多普勒超声对病理生理血流动力学的定量研究 异常现象。基于流体力学原理(射流流量理论， 动量连续性保持，中心线加速/减速， 近端流动会聚和湍流/粘性相互作用)，时间 低层事件的空间量化是可能的。数字数据 采集和分析允许的空间分辨率为0.3 mm 5毫秒的时间分辨率。量化技术已经被 应用于：1)二尖瓣返流，2)主动脉瓣返流，3) 主动脉瓣狭窄和4)人工瓣膜狭窄。三 已对主要区域进行调查：1)近端流动汇聚 和加速度分布，2)湍流/粘性相互作用和3) 反流口和狭窄口区域的动态变化。这类研究 探索基本物理原理，研究方法和 验证技术的目标是演示适用性和 无创性多普勒血流成像在临床诊断中的应用 相关量化信息。

The current year's efforts on this project have continued studies of intracardiac flow dynamics with spectral and two-dimensional color Doppler ultrasound for quantifying pathophysiologic hemodynamic abnormalities. Based upon hydrodynamic principles (jet flux theory, momentum continuity preservation, centerline acceleration/.deceleration, proximal flow convergence and turbulent/viscous interactions), temporal and spatial quantitation of low events is possible. Digital data acquisition and analysis permits spatial resolutions of 0.3 mm with temporal resolutions of 5 msec. Quantitative techniques have been applied to : 1) mitral regurgitation, 2) aortic regurgitation and 3) aortic stenosis and 4) stenotic lesions in prosthetic valves. Three major areas have been under investigation: 1) proximal flow convergence and acceleration profiles, 2) turbulent/viscous interactions and 3) dynamic changes in regurgitant and stenotic orifice areas. Such studies explore fundamental physical principles, examining methodologies and validating techniques with the goals of demonstrating applicability and utility of non invasive Doppler flow imaging to obtain clinically relevant quantitative information.