Mid term freedom from atrial fibrillation following hybrid ablation, a systematic review and meta analysis

Introduction: Atrial Fibrillation (AF) is a common tachyarrhythmia affecting 33 million people worldwide. Hybrid AF ablation utilises a surgical (epicardial) ablation followed by an endocardial catheter-based ablation. The aim of this systematic review and meta-analysis is to summarize the literature reporting mid-term freedom from AF following hybrid ablation. Methods: An electronic search of databases was performed to identify all relevant studies providing mid-term (2 year) outcomes following hybrid ablation for AF. The primary study outcome was to assess the mid-term freedom from AF following hybrid ablation, utilising the metaprop function on Stata® (Version 17.0, StataCorp, Texas, USA). Subgroup analysis was performed to assess the impact of various operative characteristics on mid-term freedom from AF. The secondary outcomes assessed mortality and procedural complication rate. Results: The search strategy identified 16 studies qualifying for inclusion in this meta-analysis, with 1242 patients in total. The majority of papers were retrospective cohort studies (15) and one study was a randomized control trial (RCT). The mean follow up was 31.5 ± 8.4 months. Following hybrid ablation, the overall mid-term freedom from AF was 74.6% and 65.4% for patients off antiarrhythmic drugs (AAD). Actuarial freedom from AF was 78.2%, 74.2% and 73.6% at 1, 2 and 3 years respectively. No significant differences in mid-term freedom from AF based epicardial lesion set (box vs pulmonary vein isolation) or Left atrial appendage/Ganglionated Plexus/Ligament of Marshall ablation or staged vs concomitant procedures. There were 12 deaths overall following the hybrid procedure with a pooled complication rate of 5.53%. Conclusion: Hybrid AF ablation offers promising mid-term freedom from AF reported at a mean follow-up of 31.5 months. The overall complication rate remains low. Further analysis of high-quality studies with randomized data and long-term follow up will help verify these results.