The Maine Vein of Marshall Ethanol Experience: Learning Curve, Efficacy, and Safety

Background The marginal benefit of ethanol infusion into the VOM as an adjunct to atrial fibrillation ablation has shown promise in a single randomized study and case series from very experienced centers. However, adoption has not been widespread and the impact on real-world outcomes outside of leading centers is not established. Objective To understand the learning curve, and explore procedural outcomes and safety with VOM ethanol infusion from a large single medical center. Methods All atrial ablation cases wherein VOM ethanol infusion was attempted were identified from the time of the program’s inception in 2019 at Maine Medical Center (Portland, ME). Our technical approach, procedural success and efficacy rates, and complications were adjudicated from the medical record. Results The overall VOM ethanol infusion success was 90%. Infusion success rates improved and fluoroscopy utilization decreased with experience. Arrhythmia recurrence was 86% after a mean follow-up of 9.5 months, with an arrhythmia-freedom probability of 80% at 12 months. Complications occurred in 5.4% of patients, including a 3.1% risk of delayed tamponade. Conclusion In our single center experience, VOM ethanol infusion was feasible with a high technical success rate and excellent arrhythmia freedom in follow-up. These positive results are balanced against a concerning rate of delayed tamponade.