Second-generation cryoballoon ablation as a first-line treatment of symptomatic atrial fibrillation: Two-year outcome and predictors of recurrence after a single procedure.

INTRODUCTION: Antiarrhythmic drug (AAD) therapy of patients with atrial fibrillation (AF) has limitations. We investigated the 2-year outcome and pre-procedural predictors of recurrence for first-line catheter ablation using the second-generation cryoballoon (CB-Adv) in a large cohort of patients with symptomatic AF.

METHODS AND RESULTS: For this prospective observational study, we enrolled 457 patients with symptomatic AF (278 paroxysmal, 179 persistent) who had no history of AAD use and who underwent pulmonary vein isolation (PVI) with the CB-Adv at our institution. Follow-up data, including Holter-ECGs, were collected during outpatient clinic visits. The impact of several variables on outcome was evaluated in univariate and multivariate analyses and Cox proportional hazards regression models. Median follow-up duration was 28 (interquartile range 15/42) months. PVI was sufficient in restoring and maintaining sinus rhythm in 79.2% (n=362) of patients. The median procedure and fluoroscopy times were 90 (72/120) and 16 (12/21) min, respectively. Phrenic nerve injury occurred in 16 (3.5%) patients, persisting until hospital discharge in 6 (1.3%) patients; phrenic nerve function recovered in all patients during follow-up. Seven patients developed groin hematomas (1.5%). Cox regression analysis showed that left atrial area >21cm2 independently predicted recurrence.

CONCLUSION: This is the first demonstration that PVI with CB-Adv is safe and effective as a first-line treatment of symptomatic AF. Sinus rhythm persisted in 79.2% of patients even 2years after ablation. The success rate was lower in patients with enlarged left atria.