Kaazempur-Mofrad M R, Ethier C R
Department of Mechanical and Industrial Engineering, University of Toronto, Ontario, Canada.
Ann Biomed Eng. 2001 Feb;29(2):121-7. doi: 10.1114/1.1349704.
The coronary arteries are a common site of atherosclerotic plaque formation, which has been putatively linked to hemodynamic and mass transport patterns. The purpose of this paper was to study mass transport patterns in a human right coronary artery (RCA) model, focusing on the effects of local geometric features on mass transfer from blood to artery walls. Using a previously developed characteristic/finite element scheme for solving advection-dominated transport problems, mass transfer calculations were performed in a rigid, anatomically realistic model of a human RCA. A qualitative and quantitative examination of the RCA geometry was also carried out. The concentration field within the RCA was seen to closely follow primary and secondary flow features. Local variations in mass transfer patterns due to geometric features were significant and much larger in magnitude than local variations in wall shear stress. We conclude that the complex secondary flows in a realistic arterial model can produce very substantial local variations in blood-wall mass transfer rates, and may be important in atherogenesis. Further, RCA mass transfer patterns are more sensitive to local geometric features than are wall shear stress patterns.
冠状动脉是动脉粥样硬化斑块形成的常见部位,一般认为这与血流动力学和物质传输模式有关。本文的目的是研究人体右冠状动脉(RCA)模型中的物质传输模式,重点关注局部几何特征对从血液到动脉壁的物质转移的影响。使用先前开发的用于解决对流主导传输问题的特征/有限元方案,在人体RCA的刚性、解剖学真实模型中进行了物质转移计算。还对RCA的几何形状进行了定性和定量检查。观察到RCA内的浓度场紧密跟随主流和二次流特征。由于几何特征导致的物质传输模式的局部变化很显著,其量级比壁面剪应力的局部变化大得多。我们得出结论,在真实动脉模型中的复杂二次流可在血壁物质传输速率中产生非常显著的局部变化,并且可能在动脉粥样硬化形成中起重要作用。此外,RCA物质传输模式比壁面剪应力模式对局部几何特征更敏感。