Dual or triple therapy in patients with atrial fibrillation and drug-eluting stents?

Abstract

Atrial fibrillation (AF) is associated with an increased risk of systemic embolization, cerebral embolism being the most catastrophic consequence. In patients with nonvalvular AF, oral anticoagulation (OAC) is especially recommended for those at medium or high risk of embolization, mainly to reduce the risk of stroke [1]. However, a percutaneous coronary intervention with stent implantation (PCI-S) requires dual-antiplatelet therapy (DAPT), commonly consisting of aspirin and a P2Y12 antagonist [2]. Between 5 and 10% of patients undergoing PCI-S are on OAC at the time of stenting. For these patients, guidelines recommend combining OAC with antiplatelet therapy, so-called triple therapy (TT), despite the increased risk of bleeding [2].Although drug-eluting stents (DES) reduce the rates of target vessel revascularization compared with bare-metal stents [3], current guidelines recommend avoiding the use of DES in patients requiring long-term OAC undergoing PCI-S owing to an increased risk of bleeding associated with the prolonged use of TT [2,4].Evidence available to date on the optimal type of stent in patients on chronic OAC yields conflicting results and the optimal antithrombotic strategy in these patients is also debated. Some studies reported a reduction in target vessel revascularization rates with an increased risk of bleeding with the use of DES in this population, whereas others found no differences in bleeding events [5,6]. The lack of randomized clinical trials and the small sample size of available studies have led to the recommendation of restricting the use of DES in patients with OAC indication.The article by Kang et al. [7], published in this journal, is a retrospective observational study carried out in two centers that analyze the net clinical outcomes between the TT and the DAPT in patients with AF after PCI-S. This is a relevant clinical problem that remains unsolved because there are few studies addressing this dilemma. The study had no exclusion criteria and the follow-up was completed for all patients. A total of 367 patients were included in the analysis and the median follow-up was 24 months. The DAPT was prescribed in 64.3% of patients and TT was administered to 35.7% of patients. A CHA2DS2-VASc score of 2 or more was significantly higher in the TT group compared with the DAPT group. The primary outcome measure was the 2-year net clinical outcomes, a composite of major bleeding and major adverse cardiac and cerebral events. Kang et al.[7] report that TT is associated with worse 2-year net clinical outcomes (34.3 vs. 21.1%, P = 0.006) with a considerable increase in the risk of major bleeding (16.7 vs. 4.6%, P < 0.001) without any definite reduction in the major bleeding and major adverse cardiac and cerebral events (22.1 vs. 17.7%, P = 0.313).At first glance, these outcomes suggest a success for DAPT without warfarin. Yet, practice should not be changed on the basis of this study alone. First, because of the retrospective nature of this observational study with a small number of patients in...