Wall Shear Stress Assessment of Aorta with Varying Low-density Lipoprotein Concentration

Abstract

Three-dimensional branched aorta has been modelled and simulated with an ambition to study wall shear stress with pulsatile blood flow and varying LDL cholesterol concentrations. LDL cholesterol is an important factor in hemodynamics and medical domain is thriving to get better sight of LDL and hemodynamics interaction to deal with numerous cardiovascular diseases. CAD modelled aorta, pulsatile blood flow, Newtonian and non-Newtonian models, convection-diffusion for LDL transport are the key tools for this study. Different published literatures considered blood as either Newtonian fluid or non-Newtonian fluid. However, both assumption is considered separately. COMSOL aided simulation yields an effective intuition about the assessment of blood velocity, its gradient and WSS for varying LDL concentration. As cholesterol concentration increased, velocity gradient adjacent to the aortic wall is found greater than the gradient in the center of aorta. Therefore, wall shear stress rises for higher concentration of LDL cholesterol. For both Newtonian and non-Newtonian models' data plots are found in similar patterns except their magnitudes. Cholesterol imbalance initiates atherosclerosis and therefore the study exhibits the potential contribution of cholesterol in wall shear stress, which is a predictor of atherosclerosis.