Development of a platform to evaluate and limit in-stent restenosis

The objective of this work was to develop a platform to evaluate and deliver putative therapeutic agents for in-stent restenosis. Arterial stenting is applied in more than 60% of balloon angioplasties for treating cardiovascular disease. However, stented arteries encounter accelerated rates of restenosis. No prior platform has allowed evaluation or local management of in-stent restenosis without perturbing the very system being examined. A stainless steel, balloon-expandable stent was modified to serve as an ablumenal drug delivery platform. Several combinations of bioerodible polymer microspheres and gels were evaluated for channel retention under in vitro flow and in vivo conditions. A stent-anchored hybrid system prevented material embolization under all conditions. Unlike prior platforms, these stents do not alter local inflammation or in-stent plaque formation relative to conventional Palmaz-Schatz stents after in vivo deployment. The system also proved sensitive enough to detect plaque reduction with an antirestenotic agent. We conclude that a platform to evaluate and deliver therapeutic agents for in-stent restenosis has been achieved.