Optimal Duration of Dual Antiplatelet Therapy after Drug-Eluting Stent Implantation: A Randomized Controlled Trial

Background—The risks and benefits of long-term dual antiplatelet therapy remain unclear.

Methods and Results—This is a prospective, multicenter, open-label, randomized comparison trial that was conducted in 24 clinical centers in Korea. In total, 5045 patients who received drug-eluting stents and were free of major adverse cardiovascular events and major bleeding for at least 12 months after stent placement were enrolled between July 2007 and July 2011. Patients were randomized to receive aspirin alone (n=2514) or clopidogrel plus aspirin (n=2531). The primary end point was a composite of death from cardiac causes, myocardial infarction, or stroke 24 months after randomization. At 24 months, the primary end point occurred in 57 aspirin-alone group patients (2.4%) and 61 dual-therapy group patients (2.6%) (hazard ratio, 0.94; 95% confidence intervals [CI], 0.66 to 1.35; P=0.75). The two groups did not differ significantly in terms of the individual risks of death from any cause, myocardial infarction, stent thrombosis, or stroke. Major bleeding occurred in 24 (1.1%) and 34 (1.4%) of the aspirin-alone group and dual-therapy group patients, respectively (hazard ratio, 0.71; 95% CI, 0.42 to 1.20; P=0.20).

Conclusions—Among patients who were on 12-month dual antiplatelet therapy without complications, an additional 24 months of dual antiplatelet therapy versus aspirin alone did not reduce the risk of the composite end point of death from cardiac causes, myocardial infarction or stroke.

Clinical Trial Registration Information—http://www.clinicaltrials.gov. Identifier: NCT01186146.

Source: circ.ahajournals.org