Comparison of two commercially available cryoballoon ablation systems

Abstract Background Cryoballoon pulmonary vein isolation (PVI) is an established anatomical single-shot procedure for the treatment of atrial fibrillation (AF). Purpose We compared efficiency of two commercially available cryoballoon ablation systems (CBS) to treat AF. Methods We prospectively enrolled 121 consecutive AF patients and treated them with either a compliant or a non-compliant CBS. Results Evaluation of procedural characteristics revealed a significantly longer procedure duration (p=0.007) and fluoroscopy time (p=0.008) in the group of the compliant CBS. The nadir cryoballoon temperature was lower using the compliant system compared to the non-compliant CBS (p<0.0001), likewise the time to isolation was not different between both groups. The non-compliant CBS showed a better occlusion for the right superior pulmonary vein (RSPV, p=0.039) leading to a higher rate of isolation with first freeze (p=0.004) and lower number of ablations at the RSPV (p=0.015). A mean follow-up period of 310.8±189.7 days within a 90-day blanking period. 68% of patients treated with the non-compliant and 65% of patients treated with the compliant CBS showed freedom from atrial arrhythmia recurrence (p=0.724). Kaplan-Meier estimation showed no significant difference between both groups (LogRank p=0.768). Conclusion The novel compliant CBS showed a longer procedure duration and fluoroscopy time, as well as, a lower nadir cryoballoon temperature. The non-compliant CBS was more effective in isolation of the RSPV. Acute PVI success and long-term freedom from atrial arrhythmia recurrence after a mean follow-up of ten months did not differ between groups.