Stent-based percutaneous coronary interventions in small coronary arteries.

A third to half of all percutaneous coronary interventions involve small diameter vessels of less than 3 mm. Small vessel size is a predictor of restenosis after balloon angioplasty, as well as after stent placement. Stents deployed in small arteries, have a higher metal-to-artery ratio; this may increase the risk of sub-acute thrombosis or restenosis. Various studies have shown that stent design, stent coating, and stent strut thickness may determine event-free survival. Dedicated stents for small vessels with less amount of metal, appropriate expansion to the vessel size with correct radial force and cells morphology, and less prothrombotic properties, may further improve the results of stenting in this setting (thinner struts, fewer cells, or loops per circumference). This review provides an update on the current status, review the major trials and define the clinical utility of small vessel stenting, particularly in the era of drug-eluting stents.