Effect of increasing porosity as drug reservoirs for local drug delivery in an auxetic stent

Stent is a small cylindrical mesh which is implanted in narrowing vessels to prevent the vessel wall from constriction. To provide more energy absorption and radial strength of the scaffold, a stent with a negative Poisson's ratio structure (auxetic) is proposed to be replaced as conventional stents. One of the most after stent implantation challenges is in-stent restenosis. Locally drug release in arteries is one of the solutions to overcome to the problem. Accordingly, drug eluted stents with different mechanisms of drug delivery are presented. In this paper, micropores are created on the surface of conventional auxetic stents as drug reservoirs. Stents are studied in two groups in non-porous and porous conditions for their mechanical properties and effectiveness. According to the analysis of the mechanical properties of porous stents, a modified model of partially porous stents is suggested and analyzed. Finally, partially porous auxetic stent is proposed as a proper choice for Drug-Eluting stents.