Stergiopulos N, Spiridon M, Pythoud F, Meister J J
Biomedical Engineering Laboratory, Swiss Federal Institute of Technology, Ecublens, Switzerland.
J Biomech. 1996 Jan;29(1):31-8. doi: 10.1016/0021-9290(95)00023-2.
This study is concerned with the wave reflection properties of arterial stenoses. Two theoretical models have been developed for deriving the reflection coefficient: a linear model resulting from the linearization of the pressure drop-flow equation and an indirect, quasi-nonlinear model, based on the separation of pressure waves into their forward and backward running components proximal and distal to the stenosis. The linear method gave consistently lower values for the reflection coefficient when compared to the quasi-nonlinear model. In vitro experiments in elastic tubes showed that the reflection coefficient is strongly dependent on stenosis severity, mean flowrate, and the elastic properties of the proximal unobstructed artery. For critical stenoses the reflection coefficient is frequency and pulsatility independent. The results suggest that hemodynamically nonsevere stenoses may cause significant wave reflections.
本研究关注动脉狭窄的波反射特性。已开发出两种理论模型来推导反射系数：一种是由压降-流量方程线性化得到的线性模型，另一种是基于将压力波分离为狭窄近端和远端向前和向后传播分量的间接准非线性模型。与准非线性模型相比，线性方法得出的反射系数值始终较低。弹性管中的体外实验表明，反射系数强烈依赖于狭窄严重程度、平均流速以及近端未阻塞动脉的弹性特性。对于临界狭窄，反射系数与频率和搏动性无关。结果表明，血流动力学上不严重的狭窄可能会引起显著的波反射。
