Anticoagulant and antiplatelet therapy in patients with atrial fibrillation undergoing percutaneous coronary intervention.

The prevalence, intensity, safety, and efficacy of oral anticoagulation (OAC) in addition to dual antiplatelet therapy (DAPT) in "real-world" patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI) have not yet been fully evaluated. In the Coronary REvascularization Demonstrating Outcome Study in Kyoto registry cohort-2, a total of 1,057 patients with AF (8.3%) were identified among 12,716 patients undergoing first PCI. Cumulative 5-year incidence of stroke was higher in patients with AF than in no-AF patients (12.8% vs 5.8%, p <0.0001). Although most patients with AF had CHADS2 score ≥2 (75.2%), only 506 patients (47.9%) received OAC with warfarin at hospital discharge. Cumulative 5-year incidence of stroke in the OAC group was not different from that in the no-OAC group (13.8% vs 11.8%, p = 0.49). Time in therapeutic range (TTR) was only 52.6% with an international normalized ratio of 1.6 to 2.6, and only 154 of 409 patients (37.7%) with international normalized ratio data had TTR ≥65%. Cumulative 5-year incidence of stroke in patients with TTR ≥65% was markedly lower than that in patients with TTR <65% (6.9% vs 15.1%, p = 0.01). In a 4-month landmark analysis in the OAC group, there was a trend for higher cumulative incidences of stroke and major bleeding in the on-DAPT (n = 286) than in the off-DAPT (n = 173) groups (15.1% vs 6.7%, p = 0.052 and 14.7% vs 8.7%, p = 0.10, respectively). In conclusion, OAC was underused and its intensity was mostly suboptimal in real-world patients with AF undergoing PCI, which lead to inadequate stroke prevention. Long-term DAPT in patients receiving OAC did not reduce stroke incidence.