Stents and antiplatelet therapy.

Coronary stents are used during the majority of percutaneous coronary interventions. When compared to medical therapy, they have been shown to decrease mortality for patients with acute coronary syndromes, and to improve symptom control in patients with stable angina. Their use, however, may be complicated by stent thrombosis (ST), a potentially fatal event. Early ST, which occurs during the first month following device implantation, is usually linked to procedural factors, with similar frequencies for bare metal stents and drug-eluting stents (DES). Late and very late (between 1 month and 1 year, respectively, and >1 year after the procedure) ST, which appear to be more frequent with DES, are due to factors such as incomplete stent apposition, delayed or dysfunctional endothelialization, and chronic inflammation. Furthermore, discontinuation of antiplatelet therapy (which includes the association of aspirin and thienopyridines) or resistance to these molecules may also lead to ST. New stent designs as well as the use of more potent antiplatelet therapies should contribute to reducing the incidence of ST in the future.