Functional Gaps and Atrial Fibrosis as Predictors of Early Arrhythmia Recurrence After Robotic‐Enhanced Hybrid Ablation for Persistent Atrial Fibrillation

Background Robotic‐enhanced hybrid ablation (RE‐HA) is a promising strategy for persistent (PsAF) and long‐standing persistent atrial fibrillation (LS‐PsAF). The impact of post‐epicardial conduction gaps and atrial fibrosis on early arrhythmia recurrence (EAR) is unclear. Objective To assess whether conduction gaps and atrial fibrosis predict EAR within 3 months after the epicardial stage of RE‐HA. Methods Forty‐two PsAF/LS‐PsAF patients underwent RE‐HA with left atrial appendage closure. High‐density endocardial mapping at 3 months identified fixed (present in all maps) and functional (present in ≥1 but not all maps) conduction gaps. Atrial fibrosis was quantified by pre‐procedural cardiac magnetic resonance (CMR). Results Gaps were found in 18 patients (42.3%): functional in 10 (23.8%) and fixed in 13 (31.0%), with 5 (12%) showing both. EAR occurred in 12 patients (28.6%), AFL in 10/12 (83.3%). Gaps predicted AFL (OR 4.56; p = 0.003) and EAR (OR 3.50; p = 0.005). Left atrium LGE ≥ 10% independently predicted EAR (OR 7.50; p = 0.019) with no interaction with gap presence ( p = 0.24). Total RF time was similar between groups despite more gaps in recurrence cases, reflecting procedural factors beyond gap count. Roof‐line gaps predominated and colocalized with epicardial fat on CMR. Conclusion Delayed high‐density mapping after RE‐HA reveals fixed and functional conduction gaps, especially at the roof line, that—together with pre‐ablation fibrosis—independently predict EAR. These findings highlight distinct anatomical and electrophysiological risk domains and support substrate assessment with targeted endocardial completion in a staged workflow.