Infusing ethanol into the vein of Marshall (VOM), in addition to catheter ablation of persistent atrial fibrillation (AF) reduces the recurrence of AF or atrial tachycardia (AT), reduces AF burden and may reduce the need for repeat procedures, according to study results presented Sunday at the American College of Cardiology Scientific Sessions 2020 virtual conference.
Miguel Valderrabano, MD, of Houston Methodist, presented findings from the VENUS (Vein of Marshall Ethanol Infusion for Persistent Atrial Fibrillation) study.
Catheter ablation of persistent AF is fraught with low single-procedure success and frequently requires repeat procedures. The objective of the study was to test whether adding VOM ethanol infusion to de novo catheter ablation of persistent AF increases the chances of maintaining normal rhythm.
The VOM is a small oblique vein that drains into the posterior wall of the left atrium.
Adult patients between 18 and 85 years with symptomatic persistent AF refractory to at least one antiarrhythmic agent were included in this study. A total of 343 patients were randomized in 1:1.15 fashion to either catheter ablation (n = 158) or catheter ablation plus VOM ethanol arm (n = 185). The primary endpoint of the study was freedom from AF or atrial tachycardia (AT) of greater than 30 seconds duration after a single procedure without the use of antiarrhythmic medications, occurring after a 3-month blanking period.
VOM ethanol plus catheter ablation led to improved freedom from AF after a single procedure in 51.6% of patients vs. 38% catheter ablation alone (p=0.017), and reduced rate of repeat procedures in 16% of VOM patients vs. 25% of ablation-only patients (p=0.02). The rate of adverse events was similar among the two arms except fluid overload, which occurred significantly more in the VOM arm (7.56% vs. 1.26%; p = 0.004).
In summary, in patients with persistent AF, Vein of Marshall ethanol added to catheter ablation reduced recurrence of AF/AT, reduced AF burden, and may reduce need for repeat procedures. Salient limitations of the study include the following: a) VOM ethanol infusion was completed in 83.8% of patients, b) VOM ethanol infusion increased the risk of fluid overload.
The study was funded by a grant from the National Heart, Lung and Blood Institute of the National Institutes of Health.