Outcomes after Catheter Ablation of Atrial Fibrillation According to the Continuation of Oral Anticoagulation Therapy

Abstract

Few recent large-scale studies have evaluated the risks and benefits of continuing oral anticoagulant（OAC）therapy after catheter ablation（CA）of atrial fibrillation（AF）. We used data from the National Database of Health Insurance Claims and Specific Health Checkups of Japan and analyzed patients who underwent CA of AF between April 2014 and March 2021. Patients were divided into two groups according to whether OAC therapy was continued 6 months after the index CA. The primary outcomes were thromboembolism and major bleeding after a landmark period of 6 months. The association between continuing OACs and outcomes was determined according to CHADS₂ score. Of 231,374 patients analyzed, 71％ and 53％ continued OAC therapy at 6 and 12 months, respectively. In the CHADS₂ score ≤ 1 group, the hazard ratio（HR）in the continued OAC group was 0.86（95％ confidence interval［CI］ : 0.74-1.01, p＝0.06）for thromboembolism and 1.51（95％ CI : 1.27-1.80, p＜0.001）for major bleeding. In the CHADS₂ score＝2 group, the hazard ratio（HR）in the continued OAC group was 0.98（95％ CI : 0.78-1.24, p＝0.90）for thromboembolism and 1.35（95％ CI : 1.05-1.72, p＝0.02）for major bleeding. In the CHADS₂ score ≥ 3 group, the HR of the continued OAC group was 0.61（95％ CI : 0.46-0.82, p＝0.001）for thromboembolism and 1.05（95％ CI : 0.71-1.56, p＝0.81）for major bleeding. Discontinuation of OACs may contribute to risk reduction of major bleeding in patients with a lower thromboembolic risk.