Though drug-eluting stents have successfully reduced restenosis rates in coronary applications, they have not proven as effective in peripheral applications. There is evidence that suggests that restenosis is driven by mechanical factors and that stent placement affects the mechanical environment about the artery. The adverse effects of stent placement can be minimized with more thoughtful consideration of the influence that the stent design has on the mechanical environment. For example, stent geometry can be optimized to minimize the stresses imposed in the artery wall, hold back intimal flaps that result from the stenting process, inhibit platelet aggregation, promote re-endothelialization, minimize flow disturbances through the stented region and minimize the mismatch in compliance between the stent and artery wall. It is important to note that some of the aforementioned concerns result in competing interests from the design perspective, e.g. the geometries that are best suited to minimize wall stresses and promote re-endothelialization are least suited to retain intimal flaps and inhibit platelet aggregation. Fortunately, these concerns are most significant along different time frames post-stent deployment. CorInnova is developing a stent technology that changes geometry and mechanical properties with time such that the design can be optimized for a given concern during the time that said concern is most significant. Note that drug-eluting stents are typically loaded with anti-proliferative medications that are designed to reconcile adverse consequences of the stenting process itself. These consequences are primarily mechanical in nature. CorInnova's approach is to minimize these adverse consequences via design features that are less devastating to the mechanical environment and thereby reduce the need for compensatory medication. The overall goal of this application is to establish proof-of-concept for a hybrid metal/polymer stent for the treatment of peripheral vascular disease where drug-eluting stents have failed. We will address this problem by designing and testing a combination of two technologies, a partially degradable stent and hemodynamically favorable stent, as a single design that collectively overcomes outstanding problems in peripheral stenting. As such, the primary focus of this proposal is to evaluate the clinical and engineering foundation of our unique stent designs to prepare for pre-clinical testing in a relevant animal model.
The overall goal of this application is to examine the efficacy of a hybrid metal/polymer stent for the treatment of peripheral vascular disease. Treatment of occlusive peripheral vascular disease with stents, particularly in the lower limbs, involves challenges not seen in coronary applications that have led to much higher clinical failure rates. As such, the primary focus of this proposal is to evaluate the clinical and engineering foundation of our unique stent designs to prepare for pre-clinical testing in a relevant animal model.