Duration of Dual Antiplatelet Therapy After Drug-Eluting Stent Implantation: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Abstract

BackgroundThe optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is unclear, and its risks and benefits may vary according to DES generation. ObjectivesThe goal of this study was to evaluate the efficacy and safety of DAPT after DES implantation. MethodsWe included randomized controlled trials that tested different durations of DAPT after DES implantation: shorter dual antiplatelet therapy (S-DAPT) was defined as the per-protocol minimum duration of DAPT after the procedure, and longer dual antiplatelet therapy (L-DAPT) was defined as the per-protocol period of more prolonged DAPT. The primary efficacy and safety outcomes were definite/probable stent thrombosis and clinically significant bleeding (CSB), respectively. ResultsTen randomized controlled trials (N = 32,135) were included. Compared with L-DAPT, S-DAPT had an overall higher rate of stent thrombosis (odds ratio [OR]: 1.71 [95% confidence interval (CI): 1.26 to 2.32]; p = 0.001). The effect of S-DAPT on stent thrombosis was attenuated with the use of second-generation DES (OR: 1.54 [95% CI: 0.96 to 2.47]) compared with the use of first-generation DES (OR: 3.94 [95% CI: 2.20 to 7.05]; p for interaction = 0.008). S-DAPT had an overall significantly lower risk of CSB (OR: 0.63 [95% CI: 0.52 to 0.75]; p < 0.001). Finally, a numerically lower all-cause mortality rate was observed with S-DAPT (OR: 0.87 [95% CI: 0.74 to 1.01]; p = 0.073). ConclusionsS-DAPT had overall lower rates of bleeding yet higher rates of stent thrombosis compared with L-DAPT; the latter effect was significantly attenuated with the use of second-generation DES, although the analysis may have been limited by the varying DAPT durations among studies. All-cause mortality was numerically higher with L-DAPT without reaching statistical significance. Prolonging DAPT requires careful assessment of the trade-off between ischemic and bleeding complications.