Análise do escoamento sanguíneo em artérias com stents utilizando interação fluido-estrutura e modelo de windkessel

Abstract

Atherosclerosis is a serious public health problem, resulting in the hardening and obstruction of arterial walls due to the accumulation of lipid cells. The use of stents has been effective in treating the disease, but restenosis is common, possibly due to unfavorable blood flow conditions near the stent. This study examines blood flow in stented arteries using fluid-structure modeling and computational hemodynamics, evaluating parameters that affect restenosis, such as shear stress and oscillatory shear index. A systematic literature review revealed few studies using Fluid-Structure Interaction (FSI) phenomenon with the Windkessel model as a boundary condition. This model is crucial in fluid dynamic simulation, capturing arterial damping and compliance characteristics. A MATLAB code was used to obtain boundary conditions in Windkessel models with three elements. Two stent models were analyzed: JANUS and Palmaz-Schatz. Computational Fluid Dynamics (CFD) and FSI analysis highlighted the importance of avoiding stent geometries that accumulate stress, potentially causing restenosis. The Windkessel model revealed the sensitivity of arterial resistance and compliance on outlet pressure, affecting the shear oscillation index and stress on the stent. Additionally, it highlighted the importance of considering fluid dynamic and structural aspects in assessing stent performance, contributing to advances in understanding and treating atherosclerosis and its complications.