Second-generation cryoballoon ablation for recurrent atrial fibrillation after an index procedure with radiofrequency versus cryo: Different pulmonary vein reconnection patterns but similar long-term outcome-Results of a multicenter analysis.

INTRODUCTION: Repeated procedures are often needed for long-term success of atrial fibrillation ablation. There are scarce data regarding cryoballoon use for such procedure. METHODS AND RESULTS: We analyzed acute effect and long-term follow-up of second-generation cryoballoon ablation, performed as a repeat procedure after an index radiofrequency vs cryoballoon ablation. Sixty-one patients from three centers were included. In 36 cases radiofrequency (RF-I) and in 25 cryoballoon ablation (CB-I) was the index procedure. During redo procedure, pulmonary vein reconnection was less frequent in CB-I vs RF-I (51.5% vs 66.9%; P = 0.017). After cryoballoon, left inferior (P = 0.027) and right superior (P = 0.06) pulmonary veins were less likely to exhibit reconnection. Moreover, patients after initial RF ablation frequently presented multiple-vein reconnection (P = 0.018), while patients after cryoablation more often had only one vein reconnected (P = 0.008). During reablation procedures, all 149 reconnected veins in both groups were isolated, with no differences in procedural parameters, except for procedure time, shorter in CB-I group (65.5 vs 71.1 minutes; P = 0.04). Transient phrenic nerve palsy was the only complication in both groups (5.6% and 8.0%; ns). After mean follow-up of 15 ± 9 months, 70.3% of patients were free from atrial fibrillation (AF), with no differences between the groups (P = 0.71). In multivariate Cox-regression analysis, the persistent form of arrhythmia (P = 0.009) and relapse in the blanking period (P = 0.0004) were the only independent predictors of AF recurrence. CONCLUSIONS: The use of second-generation cryoballoon is associated with less frequent pulmonary vein reconnection compared with RF ablation. Cryoballoon is safe and effective for repeated AF ablation, regardless of the technique used for the initial procedure.