Solid and Fluid Simulations of Vertebral Artery Stenosis Treated With Stents With Different Shapes of Link

Abstract

Stenting technology has emerged as an effective alternative for treating arterial stenosis, which recovers blood fluency through mechanical scaffold using struts. Different kinds of endovascular stents cause varying degrees of injury on the artery wall, inducing different ratios of post-operative in-stent restenosis (ISR). Therefore, the design of stent structure has a significant influence on the therapeutic effect of stent intervention. From the viewpoint of solid mechanics, the artery is subjected to long-term press by stent strut after intervention, leading to external mechanical force acting on artery. Straightening, mechanical stress, and stress concentration occurred, causing in-stent intimal hyperplasia extremely, which consequently induce ISR. From the viewpoint of hemodynamics, hemodynamic environment is changed to some extent after stenting. As a result, local blood flow is changed greatly. Vortex and low WSS occur, promoting thrombosis and intimal hyperplasia, which induce ISR more easily. To investigate the effect of stents with different links on treating stenotic vertebral artery and the relation between the shape of link and ISR, as well as provide scientific guidelines for designing stent structure and selecting stent in clinical procedure, numerical simulations of solid mechanics and hemodynamics were performed in this paper, which coupled the boundaries of stent, plaque and blood in the stented vertebral arteries using three kinds of stent with different links.