Stenting is considered to be the favoured tool for therapy of coronary stenosis disease. However, despite the many advantages of this treatment strategy, its outcome may be undermined by the restenosis occurrence in the stent deployment site. Observations have shown that stent deployment in the artery alters the hemodynamic parameters such as wall shear stress and vortices size and prepares the conditions for in-stent restenosis development. Considering this fact, in this paper, the effect of some geometrical parameters such as the shape and the size of the stent strut on the wall shear stress distribution and vortices size is investigated. Furthermore, employment of a stent with partial flexible strut is suggested to decrease the restenosis risk, and the effect of the flexible part stiffness is explored. For this purpose, the interaction between the blood flow and the flexible part is simulated by arbitrary Lagrangian-Eulerian approach in the framework of the finite element method. The results indicate that in stents with circular strut, the partial flexibility of the cross-section can be effective in reducing the restenosis risk by lowering the maximum value of the wall shear stress and considerably decreasing the vortices size. On the other hand, in stents with rectangular struts, it not only does not decrease the shear stress maximum value but also significantly increases the vortices size and may lead to increase of the restenosis risk.

Keywords: Stent, Coronary Artery, Restenosis, Wall shear stress, Vortex size, Fluid-Structure Interaction

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