Clinical Outcome of Cryoballoon Ablation for Long-Standing Persistent Atrial Fibrillation: From the Korean Cryballoon Ablation Registry

Introduction: Pulmonary vein isolation (PVI) by cryoballoon ablation (CBA) is considered an effective primary strategy for early persistent atrial fibrillation (AF). However, data regarding CBA for long-standing persistent AF (PeAF) are limited. We evaluated the efficacy and safety of CBA for long-standing PeAF compared to PeAF. Methods: The study included 1484 patients with non-paroxysmal AF from Korean CBA registry data with follow-up of > 12 months after de novo CBA. The primary outcome was recurrence of atrial tachyarrhythmias (ATs) of ≥ 30-s after a 3-month blanking period. Results: A total of 367 PeAF (25%) and 1117 long-standing PeAF (75.3%) patients (mean age 61.9 ± 9.6 years, 80% men) underwent de novo CBA. Compared to patients with PeAF, patients with long-standing PeAF had more heart failure, previous stroke or transient ischemic attack, chronic kidney disease, higher CHA₂DS₂-VASc score, and larger left atrium (LA). During a mean follow-up period of 15.1 ± 10.9 months, ATs recurrence occurred in 41.4% of PeAF and 40.1% of long-standing PeAF. Multivariate analysis showed that female gender (hazard ratio [HR]: 1.31, p = 0.01), larger LA ≥ 45 mm (HR: 1.53, p <.001) and LA volume index ≥ 51 mL/m² (HR: 1.77, p < 0.001), and longer AF duration ≥ 5 years (HR: 1. 33, p =.003) were associated with ATs recurrence. After propensity score matching, larger LA was an independent factor for ATs recurrence. Conclusions: During a long-term follow-up period after index CBA in patients with non-paroxysmal AF, ATs recurrence rate was similar between PeAF and long-standing PeAF. CBA might be an effective strategy as an initial rhythm control therapy regardless of AF type.