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 persistent AF, 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 retrospective, multicenter observational study, consecutive patients undergoing repeat CA for AF were included. The VOM–EI approach consisted of ethanol infusion followed by systematic completion of a predefined ablation setup (verification of PV isolation and assessment of conduction block across lateral mitral isthmus, left atrial dome and cavotricuspid isthmus). Patients were first analysed as VOM–EI vs non–VOM redo procedures. Propensity score matching was conducted using demographic and arrhythmia–related covariates. The primary endpoint was recurrence of atrial tachyarrhythmias ›30 seconds. Time–to–event outcomes were evaluated with Kaplan–Meier analysis and Cox regression. Secondary analysis stratified patients into three strategies—PVI–only, PVI plus substrate modification, and VOM–EI setup—comparing outcomes using inverse probability of treatment weighting (IPTW). Results A total of 263 patients undergoing repeat ablation were included (28% long–lasting persistent AF). Of these, 121 underwent VOM–EI and 142 standard redo strategies (60 PVI–only, 82 PVI plus substrate modification). After matching, 111 VOM–EI patients were compared with 111 controls. Atrial arrhythmia recurrence occurred in 42% of controls vs 20% of VOM–EI patients. In multivariate Cox regression, the VOM–EI+anatomical strategy was associated with a significantly lower risk of recurrence (HR 0.32, p=0.0001), independent of age, AF duration, and previous procedures. In IPTW analysis, VOM–EI+anatomical strategy showed favourable outcomes compared with both PVI–only and PVI plus substrate modification, with greatest benefit in patients with long–lasting AF (Figure 1). Conclusions This observational multicenter study using matched cohorts shows that VOM–EI combined with a specific predefined anatomical ablation setup is associated with improved long–term outcomes compared with standard redo strategies in a large persistent AF population.Figure 1