The evolution of coronary stents: a brief review.

Percutaneous coronary intervention is the most prevalent method for coronary artery revascularization. Initial interventions using balloon angioplasty had limited efficacy because coronary dissections, arterial recoil, and neointimal formation led to high rates of abrupt vessel closure and clinical restenosis. With the introduction of coronary stents, vascular dissections were stabilized and arterial recoil was eliminated, but neointimal accumulation remained problematic, resulting in the development of in-stent restenosis (ISR) in 20%-30% of cases. Drug-eluting stents (DESs) were developed to release antiproliferative agents at the site of arterial injury to attenuate neointimal formation. Although DESs have incrementally improved outcomes after percutaneous coronary intervention, delayed re-endothelialization and stent thrombosis remain important challenges. Herein we review the pathophysiology of ISR, stent thrombosis, and briefly summarize the clinical evidence behind first- and second-generation DESs. Moreover, we discuss advancements in our understanding of the pathogenesis of ISR and potential novel therapeutic strategies to improve clinical outcomes.