Ethanol Infusion into the Vein of Marshall Enhances Mitral Isthmus Block and Reduces Atrial Fibrillation Recurrence: A Comprehensive Meta-Analysis

Adjunctive vein of Marshall ethanol infusion (EIVOM) during atrial fibrillation (AF) ablation has emerged as a promising technique with the potential to significantly improve procedural outcomes. Despite the existing body of evidence, a comprehensive evaluation focusing on mitral isthmus block, AF recurrence, and procedural duration has not yet been conducted. This meta-analysis aims to rigorously assess the benefits of EIVOM combined with radiofrequency ablation (EIVOM-RF) compared with radiofrequency ablation alone (RF-only) in patients undergoing catheter ablation for AF or related arrhythmias. We systematically reviewed both randomised controlled trials and observational studies that compared EIVOM-RF with RF-only approaches, encompassing a total of 1,406 patients in the EIVOM-RF group and 1,849 in the RF-only group. The primary outcomes assessed included the rate of successful mitral isthmus ablation, recurrence of atrial arrhythmias, and overall procedure time. Patients treated with EIVOM-RF demonstrated a significantly lower likelihood of experiencing atrial arrhythmia recurrence compared to those receiving RF-only treatment. Furthermore, EIVOM-RF was associated with an impressive increase in the success rate of achieving mitral isthmus block. While total procedure time tended to be longer with EIVOM-RF, this difference was not only statistically significant but also highlighted substantial variability. These findings compellingly indicate that EIVOM enhances procedural efficacy, albeit at the cost of an increased procedural burden. In conclusion, EIVOM combined with RF ablation represents a transformative approach that markedly improves procedural success rates and significantly reducing arrhythmia recurrence in patients undergoing ablation for AF.