Computational fluid dynamics and stent design

Stents are small, usually metallic tubes that are intended to prop open arteries blocked with atherosclerotic plaques. While stents have been used successfully in recent years, they still suffer from failure due to development of new tissue in stented segment (restenosis). Variations in the failure rates associated with different stent designs have led researchers to investigate the role of near-wall flow patterns. While there is no direct evidence yet, the patterns of flow stagnation as the blood flows past the stent struts may affect the restenosis process. Computational fluid dynamics (CFD) approaches are well suited for obtaining detailed information on stent flow patterns. Many CFD simulations make use of a two-dimensional model. The strong dependence of flow stagnation on stent strut spacing has been clearly demonstrated. These results have been employed to interpret the results of in vitro experiments designed to elucidate the mechanisms of restenosis.