P375Triple therapy is superior to dual anti-platelet therapy in atrial fibrillation patients experiencing acute myocardial infarction with percutaneous coronary intervention

Abstract

Background: Oral anticoagulants (OACs) and dual anti-platelet therapy (DAPT) is needed to reduce thromboembolism and stent thrombosis in atrial fibrillation (AF) patients experiencing acute myocardial infarction (AMI) with percutaneous coronary intervention (PCI). Because of the increased risk of major bleeding, DAPT without warfarin is preferred to triple therapy (OACs and DAPT) in real world practice. Purpose(s): We aimed to compare efficacy and safety between triple therapy and DAPT in AF patients undergoing PCI due to AMI. Method(s): A total of 18,841AMI patients enrolled in Korean AMI Registry (KAMIR) from Nov 2011 to Dec 2016, constituting 14,748 (80.6\%) patients undergoing PCI and 1,708 (9.3\%) patients presenting AF. We analyzed consecutive 1,125 AF patients who underwent PCI and survived at hospital discharge. One-year clinical outcomes were compared between triple therapy group (n=384) and DAPT group (n=741). Primary efficacy end-point was defined as major adverse cardiac and cerebral events (MACCE), composed of death, recurrent MI, repeated PCI, and coronary artery bypass grafting (CABG), and new-onset stroke. Primary safety end-point was major bleeding. Net clinical outcome was defined as the composite of MACCE and major bleeding, Results: There were no differences in baseline clinical characteristics, and CHA2DS2-VASc score between the 2 groups. One-year mortality was higher in DAPT group (8.8\% vs. 5.2\%, p=0.032). However, there were no differences in the one-year MI, repeated PCI, CABG, and new-onset stroke between the 2 groups. Primary efficacy end-point (13.2\% vs. 7.3\%, p=0.003) was significantly higher in DAPT group, whereas primary safety end-point (0.7\% vs. 3.6\%, p=0.032) was significantly higher in triple group. Net clinical outcome was significantly higher in DAPT group (13.2\% vs. 8.3\%, p=0.032). Cox-regression analysis adjusting CHA2DS2-VASc score and clinically important covariates demonstrated that triple therapy reduced primary efficacy end-point (adjusted hazard ratio [HR] 0.60, 95\% confidence interval [CI] 0.38-0.95, p=0.029) and net clinical outcomes (adjusted HR 0.60, 95\% CI 0.38-0.95, p=0.029). Conclusion(s): Triple therapy was associated with better efficacy and worse safety clinical outcomes. However, triple therapy reduced net clinical outcomes including both efficacy and safety outcomes. Further clinical trials are warranted to prove comparative efficacy and safety between triple therapy and DAPT in AF patients experiencing AMI with PCI.