Long-term impact of vein of marshall alcohol infusion combined with an anatomical ablation setup for repeated ablation in persistent atrial fibrillation

Background The optimal ablation strategy for patients undergoing repeat catheter ablation (CA) for atrial fibrillation (AF) remains debated. Vein of Marshall ethanol infusion (VOM-EI) has been proposed to enhance substrate modification and improve long-term rhythm control, particularly in patients with persistent AF (PeAF), but its role in repeated ablations is poorly investigated. Purpose To evaluate whether adding VOM-EI to a standardized ablation setup during repeat AF ablation improves long-term rhythm outcomes compared with standard redo strategies. Methods In this prospective, multicenter observational study, consecutive patients undergoing CA for AF were included. The VOM-EI approach consisted of ethanol infusion of the vein of Marshall followed by systematic completion of a predefined ablation setup (verification of pulmonary vein isolation (PVI) and assessment of conduction block across the three main atrial isthmuses such as lateral mitral isthmus, left atrial dome and cavotricuspid isthmus). Patients were first analyzed as VOM-EI versus non-VOM redo procedures. Propensity score matching was conducted using demographic, structural, and arrhythmia-related covariates. The primary endpoint was recurrence of atrial tachyarrhythmias lasting >30 seconds. Time-to-event outcomes were evaluated with Kaplan–Meier analysis and Cox proportional hazards regression with robust variance estimates. In a secondary analysis, patients were stratified into three procedural strategies—PVI-only, PVI plus adjunctive substrate modification, and VOM-EI combined with a predefined anatomical ablation setup—and outcomes were compared using inverse probability of treatment weighting (IPTW). Results A total of 263 patients undergoing repeat ablation were included, 28% of whom had long-lasting PeAF. Of these, 121 underwent VOM-EI and 142 underwent redo ablation using standard strategies (60 PVI-only and 82 PVI combined with substrate modification). After propensity score matching, 121 VOM-EI patients were compared with 121 controls. During follow-up, atrial arrhythmia recurrence occurred in 42% of controls versus 20% of VOM-EI patients. In multivariate Cox regression, the VOM-EI+anatomical scheme strategy was associated with a significantly lower risk of recurrence (HR 0.32, p = 0.0001), independent of age, AF duration, and number of previous procedures. In the IPTW three-group comparison, VOM-EI+anatomical scheme strategy showed favorable procedural outcomes compared with both PVI-only and PVI+substrate modification, with the greatest benefit observed in patients with long-lasting PeAF. Conclusions This observational multicenter retrospective study using matched cohorts shows that VOM-EI combined with a specific predefined anatomical ablation setup seems to be associated with an improved long-term outcome compared with standard redo strategies in a large PeAF population.