This study aimed to clarify the relationship between the durability of pulmonary vein (PV) isolation and the time of phase transition from ice to water indicated by thawing plateau time in a cryoballoon ablation for atrial fibrillation (AF).
In this retrospective study, 241 PVs from 71 patients who underwent a repeat AF ablation 526 (IQR: 412, 675) days after a cryoballoon ablation were analyzed. Reconnection was observed in 101 (41.9%) PVs of 53 patients (74.6%). Thawing plateau time (TimeTP) was defined as the time from 0°C to 10°C inside the balloon in the thawing period. Durable PV isolation was associated with significantly longer TimeTP compared with PV reconnection (26.0 vs. 11.0 s,
TimeTP is an independent predictor for the durability of PV isolation, and it presents in a dose-proportional manner. TimeTP <15 s predicts long-term reconnection while TimeTP >25 s predicts durable PV isolation.