Quantifying Effect of Blood Pressure on Stress Distribution in Atherosclerotic Plaque

Plaque rupture and its ensuing thrombosis have been one of major causes of acute ischemic events relating to atherosclerosis. Therefore, it is important to make an early assessment of the plaque vulnerability and then perform a timely intervention to decrease or avoid the acute lifethreatening events. Many studies have been proposed to simulate the stress distribution in the atherosclerotic plaque using computational mechanical analysis. Most of the studies were focused on how the blood fluid velocity, plaque component/ size/shape, etc. affect the plaque vulnerability. Blood pressure (BP) has been a well-known screening factor for cardiovascular events, but the effect of BP on the stress distribution in the plaque has not been examined in depth before. In this study, the simulation was performed to investigate the variation of stress in plaque and maximum blood velocity with varying BP, as well as the differential pressure between the pressure input and output the vessel (ΔP). Under the same value of ΔP before and after the maximum ΔP, the stresses in the plaque corresponding to ΔP of descent phase were greater than that of ascent phase. The results of the study indicated that increased ΔP might cause not only the immediate increscent stress but also the slight increase to the following stress in plaque.