Influence of Carotid Artery Stenosis Location on Lesion Progression Using Computational Fluid Dynamics

Atherosclerosis is a major arterial disease characterized by the thickening of the arteries’ walls. The development of stenosis at the carotid bifurcation affects the local variations in blood flow dynamic factors. The carotid artery dynamic factors: including the wall shear stress (WSS), time-averaged wall shear stress (TAWSS) and pressure gradient affect the rate of progression of the stenosis. It is essential to analyze the flow in three-dimensional reconstructed patient-specific geometries with realistic boundary conditions to estimate the blood flow dynamic factors. Hence, a three-dimensional comprehensive model is developed including the non-Newtonian blood flow under pulsatile flow conditions. The model is numerically simulated using computational fluid dynamics solvers along with the medical imaging to investigate the effect of stenosis locations on its progression. The numerically predicted blood flow dynamic factors are analyzed. It was found that the blood flow dynamic factors have the importance to influence the diagnosis and prediction of asymptomatic carotid artery stenosis progression. Based on results, the value of TAWSS at the stenosis in the stenotic Common Carotid Artery (CCA) is 46.68 Pa comparing to 19.24 Pa and 10.049 Pa in Internal Carotid Artery (ICA) and External Carotid Artery (ECA) respectively. Also, it was found that the maximum value of WSS in the healthy artery at the bifurcation with 3.829 Pa. However, in stenotic arteries the maximum value for WSS located at the stenosis throat which was found to be 102.158 Pa for CCA comparing to 46.859 Pa in ICA and 33.658 Pa in ECA.