Duration of dual antiplatelet therapy after drug-eluting stent implantation: Meta-analysis of large randomised controlled trials

OBJECTIVE: After implantation of drug-eluting stents (DES), patients usually receive 6-12months of dual antiplatelet therapy (DAPT). However, the optimal duration of DAPT is controversial. Therefore, we performed a meta-analysis of randomized controlled trials to assess the risks and benefits of different DAPT durations. METHODS: We searched the literature using MEDLINE, Scopus, EMBASE, ISI Web of Science, Cochrane Library, ClinicalTrials.gov and recent conference proceedings, and included those trials randomizing patients to receive different durations of DAPT after DES implantation and reporting frequencies of cardiovascular and bleeding events. Data from eleven trials were analyzed using RevMan. RESULTS: Compared to 12-month DAPT treatment, extended DAPT significantly reduced the frequencies of myocardial infarction (OR 0.54 95% CI: 0.43-0.66; p<0.00001) and stent thrombosis (OR 0.36 95% CI: 0.24-0.55; p<0.00001), but the risks of major bleeding (OR 1.54 95% CI 1.22-1.96) and all-cause mortality (OR 1.43 95% CI 1.14-1.81) were substantially increased. There was no significant difference in stroke, cardiovascular mortality or repeat revascularization. Compared to short-term DAPT, 12-month DAPT or longer was associated with increased major bleeds (OR 1.98 95% CI: 1.26-3.11). No significant differences were found in the risk of other primary outcomes. CONCLUSION: 12-month DAPT appears to be a pragmatic compromise between preventing stent thrombosis and increasing bleeding risk. Patients at high bleeding risk should have shorter duration DAPT while those with low bleeding risk can be considered for DAPT beyond 12months.