Focal impulse and rotor modulation guided ablation versus pulmonary vein isolation for atrial fibrillation: A meta-analysis of head-to-head comparative studies

Introduction: Empirical pulmonary vein isolation (PVI) remains the cornerstone for catheter ablation of atrial fibrillation (AF). Various ablation strategies and modalities are continually tested with the aim of improving ablation outcomes. Although focal impulse and rotor modulation (FIRM)-guided ablation is currently used as an adjunct to PVI, evidence supporting this strategy is conflicting. We sought to examine whether the utilization of FIRM-guided ablation with or without PVI is associated with a decrease in all-atrial arrhythmia recurrence as compared to PVI alone. Methods: A systematic review of PubMed, Cochrane, and Embase was performed for head-to-head study designs comparing outcomes of patients who underwent FIRM-guided ablation with or without PVI to those who underwent PVI alone. The primary efficacy endpoint was all-atrial arrhythmia recurrence. The secondary endpoints were complications rates and procedural characteristics. Results: Overall, six studies comprising 674 patients undergoing either FIRM-guided ablation ± PVI versus PVI were included (mean age 63.4 ± 9.2, male 74%, 9% paroxysmal AF, 91% nonparoxysmal AF). After a mean follow-up of 18.8 months, FIRM-guided ablation with or without PVI was not associated with improvement in all-atrial arrhythmia recurrence rate compared to PVI alone (43.4% vs. 45.9%, risk ratio [RR]: 1.06; 95% confidence interval [CI]: 0.77–1.47; p =.70). No statistically significant difference was noted in complication rates between the two groups (RR: 1.66; 95% CI: 0.08–34.54; p =.74). Conclusion: In this meta-analysis of head-to-head comparison studies, FIRM-guided ablation with or without PVI did not provide any benefit in improving all-atrial arrhythmia recurrence at follow-up when compared to PVI alone.