Cryoballoon versus radiofrequency ablation for persistent atrial fibrillation: a systematic review and meta‑analysis.

Background: Clinical outcomes of catheter ablation for persistent atrial fibrillation (AF) remain discouraging.

Aim: This meta‑analysis aimed to compare cryoballoon ablation (CBA) with radiofrequency ablation (RFA) for persistent AF.

Methods: A systematic search of the PubMed, EMBASE, and Cochrane Library databases was performed for studies comparing the outcomes between CBA and RFA. Seven trials including 934 patients were analyzed.

Results: There were no differences between groups in terms of freedom from atrial arrhythmia (risk ratio [RR], 1.04; 95% CI, 0.93-1.15; P = 0.52; I2 = 0%), procedural complications (RR, 0.91; 95% CI, 0.52-1.59; P = 0.74; I2 = 0%), atrial fibrillation or atrial tachycardia relapse during the blanking period (RR, 0.73; 95% CI, 0.50-1.06; P = 0.1; I2 = 9%), repeat ablation (RR, 0.74; 95% CI, 0.45-1.21; P = 0.23; I2 = 62%), and vascular complications (RR, 0.98; 95% CI, 0.42-2.27; P = 0.97; I2 = 0%). Cryoballoon ablation increased the incidence of conversion to sinus rhythm during ablation (RR, 1.69; 95% CI, 1.01-2.83; P = 0.046; I2 = 0%) and phrenic nerve palsy (PNP; RR, 3.05; 95% CI, 0.95-9.8; P = 0.06; I2 = 0%), while RFA increased the risk of cardiac tamponade (RR, 0.27; 95% CI, 0.06-1.25; P = 0.09; I2 = 0%). Subanalyses revealed a lower incidence of recurrent atrial arrhythmia and repeat ablation during CBA without touch‑up RFA in pulmonary vein isolation.

Conclusions: CBA provides an alternative technique for persistent AF ablation. It might reduce the risk of repeat ablation and cardiac tamponade but increase the risk of PNP.