Abstract 16979: Posterior Wall Ablation With Cryoballoon in Persistent Atrial Fibrillation

Background: Posterior wall ablation (PWA) in addition to pulmonary vein isolation (PVI) has been suggested to improve outcomes in persistent atrial fibrillation (PeAF). Endocardial radiofrequency ablation is frequently inadequate to achieve electrical silence of PW. Aim: To contribute to the real-world data of the efficacy of PWA with cryoballoon in treating PeAF. Methods: This is a single-center, retrospective study including patients with PeAF referred for catheter ablation between 2015-2019 who underwent either PVI or PVI+PWA. PeAF was defined in accordance with current guidelines. PWA was achieved by cryoballoon; repeat map was used to confirm electrical silence (<0.05mV). Time to ablation (TTA) was defined as the time between first documented AF diagnosis and ablation. Patients were monitored for recurrence of AF or other atrial arrhythmia, defined as atrial tachycardia or flutter, through 1-year follow-up. Results: A total of 119 patients were included, 43 (36.13%) underwent PVI alone and 76 (63.87%) underwent PVI+PWA. PVI and PWA groups had similar baseline characteristics (Table 1). All patients in PWA cohort had complete electrical silence in PW. One-year follow-up occurred at a mean of 370.46 + 91.70 days after ablation. PWA was associated with decreased AF recurrence at 1-year follow up (35.90% in PVI vs 16.44% in PWA, OR 0.35, 95%CI 0.14-0.86, p = 0.023). In multivariate logistic regression, when controlling for age, longstanding persistent AF and TTA the association of PWA with decreased AF recurrence became stronger (OR 0.27, 95%CI 0.10-0.73, p = 0.010). PWA was not associated with a significantly increased rate of other atrial arrhythmia at 1-year follow-up (23.08% in PVI vs 13.70% in PWA, OR 0.53, 95%CI 0.19-1.44, p = 0.212). Conclusion: In comparison to PVI alone, PWA leads to decreased AF recurrence without increase in other arrhythmia at one year follow-up in PeAF. Cryoballoon technique may offer a more complete ablation in PW contributing to efficacy.