Prophylactic ablation during cardiac surgery in patients without atrial fibrillation: a systematic review and meta-analysis of randomized trials

OBJECTIVES: Atrial fibrillation is the most common complication of cardiac surgery and occurs frequently in patients without a history of the arrhythmia. We conducted a systematic review and meta-analysis of randomized controlled trials to assess whether prophylactic ablation during cardiac surgery in patients without a history of atrial fibrillation prevents atrial fibrillation. METHODS: We searched CENTRAL, MEDLINE and Embase from inception to August 2024. We included randomized trials of adults without a history of atrial fibrillation undergoing cardiac surgery. The intervention of interest was ablation during surgery. We pooled data using random-effects models. The primary outcome was new-onset early postoperative atrial fibrillation within 30 days following surgery. The key secondary outcome was incident clinical atrial fibrillation at follow-up (minimum 6 months). We assessed risk of bias using the Cochrane Collaboration's risk of bias tool v.2 and evidence quality using Grading of Recommendations, Assessment, Development and Evaluation (GRADE). RESULTS: We included 7 trials (n = 687). The intervention was pulmonary vein isolation in 6 trials and ganglion plexi ablation in 1. Patients who received prophylactic ablation were less likely to have early postoperative atrial fibrillation (21% vs 37%, risk ratio [RR] 0.5, 95% confidence interval 0.3-0.8, I2 = 64%) and incident clinical atrial fibrillation at longest follow-up (range 6 months-2 years; 3% vs 10%, RR 0.3, 95% confidence interval 0.2-0.7, I2 = 0%). The quality of evidence was low. CONCLUSIONS: Prophylactic ablation during cardiac surgery may prevent atrial fibrillation in patients without a history of the arrhythmia. A definitive randomized trial is needed to confirm effects and safety.