Very Long-Term Follow-Up of Pulmonary Vein Isolation Using Cryoballoon for Catheter Ablation for Atrial Fibrillation: An 8-Year Multicenter Experience

Abstract

Background: Cryoballoon pulmonary vein isolation has become an established treatment for atrial fibrillation (AF). However, data on long-term outcomes beyond 5 years are scarce. This prospective analysis aimed to evaluate the long-term outcome after cryoballoon pulmonary vein isolation.

Methods: Data from consecutive patients treated with cryoballoon pulmonary vein isolation for symptomatic AF between 2012 and 2018 in 13 institutions were analyzed. Patients with ≥5-year follow-up after the index procedure were included. Arrhythmia recurrence was defined as AF or atrial tachycardia lasting >30 seconds beyond a 3-month blanking period.

Results: A total of 1330 patients were enrolled (28.4% female patients, mean age was 60.1±10.5 years). Patients with paroxysmal AF accounted for 73.1%; the median history of AF was 36.0 (13.0-75.0) months. The rate of AF/atrial tachycardia recurrences progressively increased over time (event rate: 52.5% [49.4%-55.8%] at 8-year follow-up). A low incidence of progression to permanent AF was seen in the entire cohort (7.0%). Importantly, 15.7% of patients underwent a redo ablation for AF during follow-up; in 45.9% of these cases, all PVs were isolated at the redo procedure, with a median number of PVs isolated after the index procedure being 3 (1-4) veins. Independent predictors of arrhythmia recurrences were AF type (persistent AF: hazard ratio, 1.36 [95% CI, 1.14-1.62]; P<0.001) and chronic kidney disease (hazard ratio, 1.77 [95% CI, 1.12-2.81]; P=0.016) in multivariate analysis.

Conclusions: Cryoballoon pulmonary vein isolation as the index procedure for AF ablation resulted in a favorable long-term outcome in patients with symptomatic AF, with limited progression towards permanent AF during follow-up. Persistent AF was the strongest predictor of recurrences at long-term follow-up.

Keywords: atrial fibrillation; cardiac arrhythmias; catheter ablation; pulmonary veins; recurrence.