Meta-Analysis of Short vs. Prolonged Dual Antiplatelet Therapy after Drug-Eluting Stent Implantation and Role of Continuation with either Aspirin or a P2Y 12 Inhibitor Thereafter.

Aim: The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is an ongoing debate and novel data has emerged. The aim of this meta-analysis was to assess outcomes of short vs. control DAPT duration. In addition, the role of single antiplatelet therapy (SAPT) after DAPT with either aspirin or P2Y ₁₂ inhibitor monotherapy was analyzed.
Methods: The authors searched MEDLINE and Cochrane databases and proceedings of international meetings for randomized controlled trials (RCT) comparing ≤ 3 months with ≥ 6 months DAPT after DES implantation. The primary and co-primary outcomes of interest were definite or probable stent thrombosis (ST) and bleeding. In addition, we performed an analysis on studies who continued with either aspirin or P2Y ₁₂ monotherapy after DAPT.
Results: 9 RCTs comprising 41,864 patients were included and we analyzed a short DAPT duration of median 1.5 months vs. 12.1 months in the control group. The risk for ST was similar with short vs. control DAPT duration (0.5 vs. 0.5%; hazard ratio 1.17[95% CI 0.89-1.54]; p=0.26). Bleeding was significantly reduced with short vs. control DAPT duration (1.9 vs. 3.0%; 0.65[0.54-0.77]; p＜0.0001).ST was not different between short vs. control DAPT duration in the analysis of the 4 RCTs who continued with aspirin after DAPT and the 5 P2Y ₁₂ RCTs, respectively, and no heterogeneity was detected (p=0.861). Bleeding was also reduced with short vs. control DAPT in both the aspirin (1.2 vs. 1.7%; 0.71[0.51-0.99]; p=0.04) and P2Y ₁₂ inhibitor studies (2.1 vs. 3.4%; 0.62[0.47-0.80]; p=0.0003) and no heterogeneity was detected (p=0.515).
Conclusions: Our meta-analysis shows that short DAPT ≤ 3 months followed by SAPT reduces bleeding and is not associated with an increase in ST. The results were consistent within the aspirin and P2Y ₁₂ SAPT studies.