Antiplatelet therapy after coronary stenting.

While dual antiplatelet therapy (DAPT), after percutaneous coronary intervention (PCI) has demonstrated benefit for two important cardiovascular indications, 1) prevention of future myocardial infarction and death following acute coronary syndromes and 2) prevention of stent thrombosis, the optimal duration of treatment with dual antiplatelet therapy after coronary stent placement is not known. While current guidelines have recommended treatment with dual antiplatelet therapy for between 1 month after receiving a bare metal stent (BMS) and 6 to 12 months after PCI with a drug eluting stent (DES), there are conflicting data to guide practice. Stent thrombosis is rare, and is declining over time following improvements in procedural technique and stent design, yet definitive data regarding the timing of safe discontinuation of dual antiplatelet therapy are not yet available. Furthermore, extended duration of antiplatelet therapy beyond 6-12 months may aid in the prevention of spontaneous MI and cardiac mortality, particularly in higher risk anatomic or clinical subgroups. Moderately sized randomized trials have recently demonstrated bleeding risk associated with longer durations of therapy, but these studies have been relatively limited in their power to exclude differences in rates of stent thrombosis, or clinically significant impact on the occurrence of myocardial infarction and death in this patient population. Large randomized trials powered to examine stent thrombosis, bleeding, and mortality and myocardial infarction, are underway that are expected to guide practice in the near future. Until that time it is most prudent to continue antiplatelet therapy for at least 6-12 months after coronary stent placement in suitable patients.