Huo Yunlong, Kassab Ghassan S
PKU-HKUST Shenzhen-Hongkong Institution, Shenzhen, China.
Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing, China.
Front Physiol. 2018 May 31;9:675. doi: 10.3389/fphys.2018.00675. eCollection 2018.
A pulsatile hemodynamic analysis was carried out in the right coronary arterial (RCA) tree of control and RV hypertrophy (RVH) hearts. The shape of flow and wall shear stress (WSS) waves was hypothesized to be maintained throughout the RCA tree in RVH (i.e., similar patterns of normalized flow and WSS waves in vessels of various sizes). Consequently, we reconstructed the entire RCA tree down to the first capillary bifurcation of control and RVH hearts based on measured morphometric data. A Womersley-type model was used to compute the flow and WSS waves in the tree. The hemodynamic parameters obtained from experimental measurements were incorporated into the numerical model. Given an increased number of arterioles, the mean and amplitude of flow waves at the inlet of RCA tree in RVH was found to be two times larger than that in control, but no significant differences ( > 0.05) were found in precapillary arterioles. The increase of stiffness in RCA of RVH preserved the shape of normalized flow and WSS waves, but increased the PWV in coronary arteries and reduced the phase angle difference for the waves between the most proximal RCA and the most distal precapillary arteriole. The study is important for understanding pulsatile coronary blood flow in ventricular hypertrophy.
在对照心脏和右心室肥厚（RVH）心脏的右冠状动脉（RCA）树中进行了脉动血流动力学分析。研究假设在RVH中，整个RCA树中血流和壁面切应力（WSS）波的形状保持不变（即，不同大小血管中归一化血流和WSS波的模式相似）。因此，我们根据测量的形态学数据重建了对照心脏和RVH心脏直至第一个毛细血管分支点的整个RCA树。使用沃默斯利型模型计算树中的血流和WSS波。将从实验测量中获得的血流动力学参数纳入数值模型。鉴于小动脉数量增加，发现RVH中RCA树入口处血流波的平均值和幅度比对照中的大两倍，但在毛细血管前小动脉中未发现显著差异（>0.05）。RVH的RCA中刚度增加保留了归一化血流和WSS波的形状，但增加了冠状动脉中的脉搏波传播速度（PWV），并减小了最近端RCA与最远端毛细血管前小动脉之间波的相位角差。该研究对于理解心室肥厚中的脉动性冠状动脉血流具有重要意义。
