Optimal stent design: past present and future

摘要

Coronary stent implantation is the standard of care in percutaneous coronary interventions, offering a better outcome in the short and long term. The main limitation of bare-metal stents is in-stent restenosis resulting from neointimal hyperplasia, associated with a substantial rate of target lesion revascularization. Drug-eluting stents reduced in-stent restenosis and repeat revascularization; however, late stent thrombosis has been the main concern with regards to this technology. Chronic inflammatory and hypersensitivity reactions to the polymer of drug-eluting stents were implicated in the predisposition to stent thrombosis. Second-generation drug-eluting stents with biocompatible and biodegradable polymers promised a better safety outcome. Moreover, studies on novel antiproliferative and polymer-free drug-eluting stents demonstrated at least comparable angiographic late loss. Early-phase studies on bioabsorbable vascular scaffolds demonstrated substantial late loss: a combination of neointimal hyperplasia and chronic scaffold recoil. Some stents with bioactive coating, such as titanium-nitride-oxide-coated, and endothelial progenitor cell-capturing stents showed promising safety and efficacy outcomes.