Ethanol infusion into the vein of Marshall reduced atrial tachyarrhythmia recurrence during catheter ablation: A systematic review and meta-analysis

Background

Ethanol infusion into the vein of Marshall (EIVoM) may increase mitral isthmus bidirectional block (MIBB) and cause local autonomic denervation that may improve outcome.

Objective

This meta-analysis aimed to investigate whether the addition of EIVoM to atrial fibrillation (AF) ablation led to a better outcome.

Methods

Systematic literature search was performed using PubMed, Scopus, ScienceDirect, and Europe PMC for studies that compared the addition of EIVoM during AF ablation with radiofrequency ablation. The primary outcome was atrial tachyarrhythmia (ATa) recurrence, defined as AF/atrial flutter/atrial tachycardia after the blanking period.

Results

There were 2821 patients from 11 studies, and EIVoM was successful in 77% (95% confidence interval [CI] 62%–92%). ATa recurrence was 27% (95% CI 20%–34%) in the EIVoM group and 42% (95% CI 33%–51%) in ablation-only group. EIVoM reduced ATa recurrence (odds ratio [OR] 0.52; 95% CI 0.36–0.76; P < .001; I² = 76.92). The rate of MIBB was 85% (95% CI 77%–94%) in the EIVoM group and 73% (95% CI 61%–85%) in the ablation-only group, which was significantly higher (OR 3.87; 95% CI 1.46–10.28; P < .001; I² = 83.68). The mitral isthmus reconnection rate (OR 0.44; 95% CI 0.15–1.29; P = .14; I² = 63.6) and repeat procedure rate (OR 0.76; 95% CI 0.53–1.08; P = .12; I² = 48) were similar; however, a leave-one-out sensitivity analysis showed P < .05 for both. The benefits of EIVoM were not affected by age, left atrial diameter, and left ventricular ejection fraction (P > .05). Age (P = .029) and left atrial diameter (P = .042) were inversely associated with EIVoM benefits in terms of repeat ablation and mitral isthmus reconnection (age; P = .003).

Conclusion

The addition of EIVoM to ablation increased MIBB and reduced ATa recurrence.