Time-to-Isolation Under 30 s as a Predictor of Long-Term Pulmonary Vein Isolation Following Cryoballoon Ablation in Atrial Fibrillation

Objective: This study aims to examine the association between the time to isolation (TTI) during cryoballoon ablation (CBA) and long-term durability of pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). Methods: A retrospective analysis was conducted involving 104 patients with AF who underwent repeat ablation at Fujian Provincial Hospital between June 2016 and March 2023. Pulmonary veins (PVs) with electrical reconnection were identified using left atrial voltage mapping during the repeat procedure. The association between TTI recorded during the initial procedure and subsequent PV reconnection was analyzed. PV reconnection rates were compared across TTI groups (30, 31–35, 40, and 45 s). Additionally, the temperature at 30 s and at TTI during the initial procedure were evaluated. Results: The PV reconnection rate was significantly lower in patients with TTI < 30 s compared with those with TTI ≥ 30 s (21.72% vs 34.83%, p = 0.03). For TTIs < 30 s, the sensitivity, specificity, and positive predictive value for durable PV electrical isolation were 35.12%, 76.92%, and 78.26%, respectively. Conclusion: A TTI of <30 s during CBA may serve as a predictor of durable PV electrical isolation in patients with AF.