Vein of Marshall Ethanol Infusion Related Lesion Durability: Looking for the Real Scar. Center-Cluster, Case-Control...

Vein of Marshall ethanol infusion (VOM-EI) in patients with Atrial Fibrillation (AFib) triggers local injury, which may increase the subsequent radiofrequency catheter ablation (RFCA) success rate in persistent atrial fibrillation (PeAF). The long-term durability of VOM-EI induced low-voltage area (LVA), might condition the success of RFCA after VOM-EI. We hypothesized that the amount of LVA after VOM-EI decreases over time.

Consecutive patients with recurrent PeAF and no history of previous ablation were enrolled in this prospective, center-cluster, case-control study. In the experimental group, RFCA was performed 1 month after VOM-EI. In the control group, VOM-EI and RFCA were performed concomitantly. The primary endpoint was the bipolar VOM-EI LVA measured immediately prior to RFCA.

We studied 80 consecutive patients who met the inclusion criteria. The two groups did not differ in baseline characteristics. The mean bipolar VOM-EI-LVA measured before RFCA was significantly smaller in the 40 patients who underwent VOM-EI 1 month earlier than in the group of 40 patients who underwent the standard procedure (2.6 ± 2.4 vs. 10.0 ± 7.0 cm², p = 0.012). At a mean follow-up of 19.6 ± 7.3 months, freedom from AF/AT recurrences was promisingly higher in the investigational group compared to the control group (90.0% vs. 82.5%).

These data suggest that the endocardial newly-formed lesion induced by VOM-EI decreases over time, probably due to progressive resolution of perilesional oedema. These results merit larger studies testing the hypothesis that postponing RFCA 1 month after VOM-EI may increase its effectiveness in terms of fewer recurrences of atrial fibrillation.