Background: Atrial fibrillation increases thromboembolic risk. Oral anticoagulation with antivitamin K (AVK) reduces thromboembolic event rate, but increases hemorrhagic risk.
Objective: The aim of the present study was to describe long-term cerebral thromboembolic/hemorrhagic event rates in atrial fibrillation patients managed by rhythm control, pursued by atrial fibrillation transcatheter ablation (AFTCA), and rate control strategy.
Methods and results: One thousand and five hundred consecutive patients referring to three medical care centers for atrial fibrillation were retrospectively divided into three groups: AFTCA maintaining AVK (group A); AFTCA discontinuing AVK (group B); and rate control strategy and AVK (group C). Thromboembolic and hemorrhagic events were recorded in 60 ± 28 months of follow-up. Thromboembolic events did not differ between the groups (5/500, 1% group A; 7/500, 1.4% group B; 11/500, 2.2% group C; P = 0.45), and hemorrhagic events were greater in group A (9/500, 1.8%) and C (12/500, 2.4%) than in group B (no events; P = 0.003). Among patients with CHA2DS2 VASc score 2 or less, thromboembolic events did not differ in the group discontinuing AVK (group B, 4/388, 1%) or not (group A, 1/319, 0.3%; P = 0.38), whereas hemorrhagic events were more common in patients on AVK (5/319, 1.5% group A and 3/175, 1.7% group C; P = 0.02) compared with those discontinuing AVK (0/388, group B). Following AFTCA (groups A and B), 299/1000 experienced atrial fibrillation relapses; all thromboembolic events (12/299, 4%) occurred within these patients (P < 0.001).
Conclusion: Considering this multicenter design study, AVK continuation following AFTCA, especially within patients with low-to-intermediate thromboembolic risk, confers a hemorrhagic risk greater to the thromboembolic protective effect. All thromboembolic events following AFTCA occur within patients experiencing atrial fibrillation relapses; therefore, in patients with high thromboembolic risk routine rhythm monitoring is essential after AVK discontinuation.