Comparative study on hemodynamic environments around patient-specific carotid atherosclerotic plaques with different symmetrical features

Atherosclerotic plaque near the carotid sinus is a key risk factor for ischemic stroke. Although disturbed hemodynamic environments around atherosclerotic plaque had been investigated in many studies, the effect of their symmetrical features, especially longitudinal asymmetrical characteristics, had not been comparatively studied. In this study, three-dimensional carotid bifurcation models were established based on CT images of three patients with 50% stenosis and with different symmetrical features of carotid atherosclerotic plaques including concentric plaque, eccentric plaque, or eccentric longitudinal asymmetrical plaque. A healthy subject was chosen as the control. Wall shear stress (WSS) and oscillating shear index in the regions of upstream, downstream, downstream shoulders and regions around the point of maximum stenosis were analyzed. The results indicated that the maximum WSS around the eccentric longitudinal asymmetrical plaque were 8.6 times larger than that of the eccentric plaque and 1.9 times larger than that of the concentric plaque. And the distributions of WSS and OSI around the eccentric longitudinal asymmetric plaque were more disordered than those of the others. Our results highlighted the risk of the eccentric longitudinal asymmetrical plaque on plaque development and rupture and might provide a new index for evaluating the development of atherosclerosis.