Second-generation cryoballoon ablation for treatment of persistent atrial fibrillation: Three-year outcome and predictors of recurrence after a single procedure.

Introduction: Data on long-term outcomes of cryoballoon (CB) ablation for treatment of persistent atrial fibrillation (AF) are sparse. Here, we report the first 3-year follow-up results and predictors of success for catheter ablation using the second-generation CB in patients with persistent AF. Methods and results: For this prospective observational study, we enrolled 101 patients ablated with the second-generation CB at our institution. The endpoint was the first documented recurrence (>30 seconds) of AF, atrial flutter, or atrial tachycardia after a 3-month blanking period. Follow-up data were collected during outpatient clinic visits and included Holter-ECG recordings. The impact of several variables on recurrence was evaluated by means of univariate and multivariate analyses and Cox proportional hazards regression models. After a median follow-up of 37 (31 of 42) months, recurrence was documented in 30 patients (29,7%), The median procedure and fluoroscopy times were 120 (102 of 147) and 20 (16 of 27) minutes, respectively. Phrenic nerve palsy occurred in 2.0% of the patients. Among the 30 patients who experienced recurrence, 16 underwent repeat ablation in radiofrequency technique. Cox regression analysis showed that left atrial area >21 cm(2) and AF history duration >2 years independently predicted recurrence. Conclusions: Sinus rhythm was maintained in a substantial proportion of patients even 3 years after CB ablation. Patients with a nonenlarged left atrium and short AF history had the best outcome.