- Question
- Does adding vein of Marshall ethanol infusion to catheter ablation improve outcomes in persistent atrial fibrillation?
- Design
- Investigator-initiated, NIH-funded, randomized, single-blinded trial conducted at 12 centers in the United States, with 343 randomized patients (1:1.15 allocation to allow for technical infusion failures). Outcome assessment was blinded to treatment assignment.
- Population
- Patients with persistent atrial fibrillation referred for a first ablation; mean age 66.5 years, 261 men.
- Intervention
- Catheter ablation combined with retrograde ethanol infusion into the vein of Marshall (185 patients; ethanol was successfully delivered in 155).
- Control
- Catheter ablation alone (158 patients).
- Primary outcome
- Freedom from atrial fibrillation or atrial tachycardia lasting longer than 30 seconds after a single procedure, off antiarrhythmic drugs, at both 6 and 12 months.
- Results
- Freedom from AF/atrial tachycardia was 49.2% (91/185) with ethanol plus ablation vs 38% (60/158) with ablation alone (difference 11.2%; 95% CI 0.8%-21.7%; P = .04). Perimitral block success was also higher (80.6% vs 51.3%; P < .001), while 9 of the 12 secondary outcomes did not differ significantly.
- Safety
- Adverse events were similar between the two groups.
- Conclusion
- In persistent AF, adding vein of Marshall ethanol infusion to catheter ablation increased the likelihood of remaining free of AF or atrial tachycardia at 6 and 12 months.
- Why it matters
- It provided randomized evidence that a substrate-modification strategy beyond pulmonary vein isolation can improve ablation outcomes in persistent AF, although longer-term efficacy still needs to be assessed.
Card generated automatically with AI from the abstract of the original publication and the trial registry; every figure was checked against those sources. It may contain errors: verify the data at the source before using it for clinical decisions.
Generated on October 15, 2026