Safety and Efficacy of Triple Antithrombotic Therapy with Dabigatran versus Vitamin K Antagonist in Atrial Fibrillation Patients: A Pilot Study

Background. Combination of dual antiplatelet (DAPT) and oral anticoagulation therapy is required to decrease cardioembolic stroke and stent thrombosis risk in patients with atrial fibrillation (AF) and acute coronary syndrome (ACS). We compared the safety and efficacy of dabigatran etexilate with vitamin K antagonist (VKA), in combination with DAPT (aspirin plus clopidogrel) treatment in AF patients who underwent percutaneous coronary intervention (PCI) with stenting for ACS. Methods. Consecutive nonvalvular AF patients who received twice-daily dabigatran 110 mg (n = 389) or VKA (n = 510) and DAPT were included. Primary endpoints were major bleeding (safety) and the composite of ischemic stroke, systemic embolism, and myocardial infarction (efficacy). The secondary efficacy endpoint was hospitalization for cardiovascular disease. Results. After propensity score matching, comparative treatment groups comprised 175 dabigatran recipients and 175 VKA recipients. The cumulative incidence of major bleeding was lower in the dabigatran group (2.3%) compared with the VKA group (10.3%) with a hazard ratio (HR) of 4.81 [95% confidence interval (CI) 1.6-14.2, p < 0.005]. The cumulative incidence of thromboembolic events with dabigatran was slightly higher (8.0%) than with VKA (6.85%), but not statistically significantly so (0.8, 0.39-1.8; p = 0.6). Cumulative incidence of hospitalization for cardiovascular disease was lower with dabigatran (10.3%) compared with VKA (20.6%) treatment (2.2, 1.25-3.8; p < 0.006). Conclusion. Dabigatran at the dose used for stroke prevention appears safer than VKA and maintains a similar efficacy profile, when used with DAPT, in AF patients who have undergone PCI with stenting for ACS.