Impedance of arterial system simulated by viscoelastic t tubes terminated in windkessels.
Impedance of arterial system simulated by viscoelastic t tubes terminated in windkessels.
复制标题
通过终止于风桶的粘弹性 T 管模拟动脉系统的阻抗。
DOI：
10.1152/ajpheart.1989.256.4.h1087
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Yin,FC
中科院分区：
文献类型：
--
作者：
Liu,ZR;Shen,F;Yin,FC
提出了一种改进的动脉系统非对称T管模型。该模型由两个不同长度的粘弹性管组成，每个管的末端都是一个带有电感、阻力和柔度的改进型风管。给出了该模型输入阻抗的计算公式。使用文献中的典型数据，该模型预测的阻抗模数和相位比以前的环流模型更接近实际。参数分析表明，当外围柔度改变时，阻抗谱的极低频部分产生尖锐的峰值，而端子的特性阻抗或电感的改变对输入阻抗几乎没有影响。管的弹性或相对长度的改变导致最大值和最小值的位置移动，与实验观察到的位置相似。壁或血液粘度的变化只影响阻抗谱的波动，而不影响最大值和最小值的位置。因此，使用这个仍然简单的模型，可以得到非常真实的阻抗谱。该模型提供了比先前提出的模型更深入地了解近端和外周血管系统的各种参数对中枢血流动力学的个体影响。
An improved asymmetric t-tube model of the arterial system is proposed. The model consists of two viscoelastic tubes of differing lengths, each terminated in a modified windkessel with inductance as well as resistance and compliance. Equations for calculating the input impedance of this model are presented. Using typical data from the literature, the model predicts a more realistic impedance modulus and phase than previous models of the circulation. Parametric analysis shows that when peripheral compliances are altered, sharp peaks in the very low frequency portions of the impedance spectra are produced, whereas alterations of either the characteristic impedances or inductances of the terminations have little effect on input impedance. Alteration of the elasticity or relative lengths of the tubes results in shifts in the positions of the maxima and minima akin to those observed experimentally. Change in the viscosity of the walls or of the blood only affects the fluctuations of the impedance spectra without affecting the positions of the maxima and minima. Thus, with this still simple model, very realistic impedance spectra are obtainable. The model provides more insight than previously proposed models into the individual influence of various parameters of the proximal and peripheral vasculature on central hemodynamics.