Factors associated with silent cerebral events during atrial fibrillation ablation in patients on uninterrupted oral anticoagulation

Introduction: Silent cerebral events (SCEs) are related to the potential thromboembolic risk in atrial fibrillation (AF) ablation. Periprocedural uninterrupted oral anticoagulation (OAC) reportedly reduced the risk of SCEs, but the incidence still remains. Methods and Results: AF patients undergoing catheter ablation were eligible. All patients took non–vitamin K antagonist oral anticoagulants (NOACs; n = 248) or vitamin K antagonist (VKA; n = 37) for periprocedural OAC (>4 weeks) without interruption during the procedure. Brain magnetic resonance imaging was performed within 2 days after the procedure to detect SCEs. Clinical characteristics and procedure-related parameters were compared between patients with and without SCEs. SCEs were detected in 66 patients (23.1%; SCE[+]) but were not detected in 219 patients (SCE[−]). Age was higher in SCE[+] than in SCE[−] (66 ± 10 vs. 62 ± 12 years; p <.05). Persistent AF prevalence, CHADS₂/CHA₂DS₂-VASc scores, serum NT-ProBNP levels, left atrial dimension (LAD), and spontaneous echo contrast prevalence in transesophageal echocardiography significantly increased in SCE[+] versus SCE[−]. SCE[+] had lower baseline activated clotting time (ACT) before heparin injection and longer time to reach optimal ACT (>300 s) than SCE[−] (146 ± 27 vs. 156 ± 29 s and 44 ± 30 vs. 35 ± 25 min; p <.05, respectively). In multivariate analysis, age, LAD, baseline ACT, and time to reach the optimal ACT were predictors for SCEs. The average values of the ACT parameters were significantly different among NOACs/VKA. Conclusion: Age, LAD, and intraprocedural ACT kinetics significantly affect SCEs during AF ablation. Different anticoagulants have different impacts on ACT during the procedure, which should be considered when estimating the risk of SCEs.