Stent Geometry Optimization for In-Stent Restenosis Prevention Through Fluid–Structure Interaction Analysis

Abstract

AbstractHeart attacks are the most common cause of death in the world in the last decade. Heart attacks are caused by a deficiency of nutrients in the heart muscle cells due to blood flow blockage. Blocked blood flow can be restored by the deployment of a medical device called a stent. However, many studies found that stent deployment may induce plaque formation, known as in-stent restenosis. Previously, there have been attempts to minimize in-restenosis occurrence on stents by redesigning the stent. Optimization algorithms and numerical simulations are employed to search for the best stent design according to preset objective functions and constraints. This paper studies the optimum stent configuration considering the extensively studied restenosis risk factors, such as intimal stress and wall shear stress. For the optimization, a genetic-based optimization algorithm (GA) was used. The risk factors occurrence is analyzed by coupling finite element method (FEM) and computational fluid dynamics (CFD) solvers. Several conflicting objective functions based on the analyzed risk factors and constraints are also applied to the optimization algorithm. As a result, optimum stent configurations are obtained, which have the best size and angles of struts.KeywordsFluid–structure interactionFinite element methodGenetic algorithmIschemic heart diseasesIn-stent restenosisStent