Wall Shear Stress Change Due to Arterial Wall Stiffness; Fluid-Solid Interactions Study

Blood flow plays an important role in regulating blood vessel structure and developing vascular pathology such as atherosclerosis. Of particular importance is the role of the shear stress on a surface of the blood vessel, which is known as wall shear stress (WSS). It is recognized today that atherosclerosis develops in areas where the WSS is low, i.e., low-shear hypothesis by Caro et al., therefore, many researchers have been studying WSS distribution in time and space in order to predict the precise region where atherosclerosis occurs by CFD simulations. Practically, however, most of the studies involve an assumption that the arterial wall is rigid. Although this assumption is widely accepted, arterial wall movements during the pulse propagation should be considered for more detailed information. Recently, we have considered the effects of arterial wall motion on WSS by fluid-solid interactions analysis, and showed that the contribution of the wall motion to the WSS is up to 1.0 Pa. In this study, we assessed the influence of the arterial wall stiffness on WSS during the pulse wave propagation.