Phrenic Nerve Damage After Atrial Fibrillation Ablation Using Second Generation Cryoballoon

Objective: Cryoballoon ablation is a safe alternative to radiofrequency ablation in the treatment of atrial fibrillation. However, phrenic nerve damage is a bothersome complication of the procedure. In this study, we aimed to establish the incidence of phrenic nerve damage during cryoballon ablation and define the characteristics of affected patients. Material and Methods: In this retrospective analysis, all patients with atrial fibrillation that underwent cryoballoon ablation between 2013 and 2018 were included into the study. Characteristics and outcomes of patients complicated with phrenic nerve damage were evaluated. Phrenic nerve damage was detected by palpation of diaphragma contractions or observation of reduced diaphragma motility by fluoroscopy during the procedure. Results: Totally 653 patients were included in the study. Phrenic nerve damage was detected in 3.5% (23/653) of the patients. Median age of the patients with PNP was 56 (25-78) years and 10 patients (43.4 %) were male. The most common ablation site related with phrenic nerve damage was right superior pulmonary vein (18 patients, 78%). Transient phrenic nerve damage was observed in 16 patients (69%) of the patients which resolved within 24 hours after the procedure. In the remaining 5 patients (21%) diaphragmatic contraction was recovered at the 6th month control visit. In 2 patients (10%), phrenic nerve paralysis was still present 1 year visit. Conclusion: Phrenic nerve damage is not a rare complication of cryoballoon ablation despite all the preventive maneuvers during the procedure and technological developments. However, most of the phrenic nerve damage recovered during the follow-up.