Clinical recurrence and electrical pulmonary vein reconnections after second-generation cryoballoon ablation

BackgroundElectrical reconnections after pulmonary vein isolation (PVI) are less common after second-generation cryoballoon than radiofrequency ablation.ObjectiveThe purpose of this study was to investigate the incidence and characteristics of pulmonary vein (PV) reconnections after second-generation cryoballoon ablation in patients with and those without clinical recurrences.MethodsForty patients with paroxysmal atrial fibrillation undergoing second procedures after cryoballoon ablation were enrolled. Twenty-five patients experienced clinical recurrences, and the remaining 15 did not.ResultsAll 158 PVs were reevaluated a median [25th, 75th percentiles] of 6.0 [4.0–9.0] months after the initial procedure. In total, reconnections were detected in 39 PVs (24.7%) among 25 patients (62.5%). Reconnected PVs included 6 left superior (LS) (15.8%), 7 left inferior (LI) (18.4%), 5 right superior (RS) (12.5%), 20 right inferior (RI) (50.0%), and 1 left common (LC) (50.0%) PV. Reconnected PV potential conduction delays were a median of 112 [76–130], 103 [82–133], 84 [66–96], 68 [49–73], and 204 ms in the LS, LI, RS, RI, and LC PV, respectively. There was no significant difference between those with and those without clinical recurrences with regard to clinical characteristics, procedural results, incidence of reconnections (25/98 vs 14/60, P = .758), and PV conduction delays in each PV. The most common gap location was the RI PV bottom in both groups. Among 5 patients with reconnections of arrhythmogenic PVs (with atrial fibrillation initiation), 2 experienced clinical recurrences, whereas 3 did not. Non-PV foci (with atrial fibrillation initiation) were identified in a second procedures in 10 of 25 patients with clinical recurrences.ConclusionThe incidence and characteristics of PV reconnections after second-generation cryoballoon ablation were similar between patients with and those without clinical recurrences. The results should be considered when discussing the optimal dose of cryoballoon applications.