Long-term follow-up of pulmonary vein cryoballoon isolation using a double 120s vs single 240s standard freeze protocol

Background Recently, pulmonary vein isolation (PVI) using a double 120s freeze protocol has demonstrated to be non-inferior to a single 240s protocol despite a potentially increased procedural safety. Main advantages of a double 120s protocol are a reduction of phrenic nerve injury and an increase of the mean minimal esophageal temperature during the procedure. Methods We performed a long-term follow-up comparison between groups of patients with history of symptomatic atrial fibrillation undergoing PVI with second generation cryoballoon (CB) between 2019 and 2020. Our usual energy dosing protocol was modified including 2 times 120 seconds applications instead of a single 240 seconds application. Of A total of 160 consecutive patients, 80 were treated with double 120s (CB120) and 80 with single 240s (CB240) freeze protocol. 107 patients were, successfully, followed-up. The primary end-point was freedom from atrial tachyarrhythmia. Results Before PVI a total of 11/52 patients (21%) had persistent AF and 41/52 (79%) had paroxysmal AF in the CB120 group; a total of 20/55 patients (36%) had persistent AF and 35/55 (64%) had paroxysmal AF in the CB240 group. On a mean follow-up time of 17 months, freedom from atrial tachyarrhythmia was 63% in those patients undergoing CB240 and 74% with CB120 (log-rank P=0.255). Conclusions The double 120s freeze protocol is not-inferior as compared to the standard 240s in terms of freedom from recurrences on a long term follow-up, but with a more favorable procedural safety profile.