Meta-Analysis of Randomized Clinical Trials Comparing Short-Term Versus Long-Term Dual Antiplatelet Therapy Following Drug-Eluting Stents
Current guidelines recommend 12 months of dual antiplatelet therapy (DAPT) after drugeluting stent (DES) implantation in the absence of increased bleeding risk. Studies have suggested that early discontinuation of DAPT can result in an increased risk of stent thrombosis. However, given the potential for major bleeding, the optimal duration of DAPT after DES implantation remains uncertain. We searched PubMed, EMBASE, Scopus, and ClinicalTrials.gov databases from inception until October 2013 for randomized controlled trials that compared shorter versus longer DAPT duration after DES implantation. Four randomized controlled trials were included. A total of 4,081 patients received DAPT for 3 to 6 months, and 4,076 patients were treated with DAPT for 12 to 24 months. Oral DAPT consisted of aspirin and clopidogrel. There was no significant difference in the rate of the composite outcome of cardiac death or myocardial infarction between the short (3.3%) and prolonged (3.0%) DAPT groups (odds ratio 1.11, 95% confidence interval 0.87 to 1.43, p [ 0.41). A landmark analysis performed at the time of discontinuation of DAPT in the short DAPT group demonstrated a nonsignificant higher rate of stent thrombosis in patients treated with a short course of DAPT (0.35% vs 0.20%, p [ 0.22). Major bleeding was significantly higher in the group of patients treated with prolonged DAPT (0.29% vs 0.71%, p [ 0.01).
In conclusion, prolonged DAPT compared with short-term treatment is associated with increased major bleeding but is not associated with a decrease in the composite rates of death or myocardial infarction.