Cryoballoon versus radiofrequency ablation for atrial fibrillation: A meta-analysis of 16 clinical trials

Introduction: We aimed to study the procedural characteristics, efficacy and safety of cryoballoon ablation (CBA) versus radiofrequency ablation (RFA) for catheter ablation of paroxysmal atrial fibrillation (AF). Methods: A systematic literature search was performed using Pub Med, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials to clinical trials comparing CBA and RFA for AF. Outcomes were evaluated for efficacy, procedure characteristics and safety. For each study, odd ratio (OR) and 95% confidence intervals (CIs) were calculated for endpoints for both approaches. Results: We analyzed a total of 9,957 participants (3,369 in the CBA and 6,588 in RFA group) enrolled in 16 clinical trials. No significant difference was observed between CBA and RFA with regards to freedom from atrial arrhythmia at 12-months, recurrent atrial arrhythmias or repeat catheter ablation. CBA group had a significantly higher transient phrenic nerve injury (OR 14.19, 95% CI: 6.92-29.10; p<0.001) and persistent phrenic nerve injury (OR 4.62, 95% CI: 1.97-10.81; p<0.001); and a significantly lower pericardial effusion/cardiac tamponade (OR 0.43, 95% CI: 0.26-0.72; p=0.001), and groin site complications (OR 0.60, 95% CI: 0.38-0.93; p=0.02). No significant difference was observed in overall complications, stroke/thromboembolic events, major bleeding, and minor bleeding. Conclusion: CBA was non-inferior to RFA for catheter ablation of paroxysmal AF. RF ablation was associated with a higher groin complications and pericardial effusion/cardiac tamponade, whereas CBA was associated with higher rates of transient and persistent phrenic nerve injury.