The Current Status of Coronary Drug-Eluting Stents

Percutaneous coronary intervention is currently the most common revascularization procedure for coronary artery stenosis. Bare metal stents effectively reduce the rates of acute closure and restenosis more successfully than balloon angioplasty. However, the rates of restenosis remain high. Local delivery of drugs using drug-eluting stents to inhibit neointimal pro liferation was proven to be an effective method to reduce in-stent restenosis and hence the rates of target lesions and target vessel revascularization. At present, four drug-eluting stents have been approved by the Food and Drug Administration, including the sirolimus-eluting stent (Cypher), paclitaxel-eluting stent (Taxus), zotarolimus-eluting stent (Endeavor) and everolimus-eluting stent (Xience V). These four drug-eluting stents are effective in reducing in-stent restenosis, and target vessel and lesion revascularization in comparison with bare metal stents. However, the mortality and myocardial infarction rates were similar between bare metal stents and drug-eluting stents. Recently, late and very late stent thrombosis resulting in high rates of mortality and myocardial infarction have become important issues. Discontinuation of dual antiplatelet therapy appeared to be the main etiology of late and very late stent thrombosis. Dual antiplatelet therapy for at least 12 months after deployment of drug-eluting stents is currently recommended by the ACC/AHA guidelines.