The VENUS trial results, which demonstrated a benefit of adding an ethanol infusion to the vein of Marshall during catheter ablation of persistent atrial fibrillation (AF), are now published.
Combining catheter ablation with vein of Marshall ethanol infusion is increasingly being used in the United States to increase the chances of maintaining normal rhythm, lead investigator Miguel Valderrábano, MD, Methodist DeBakey Heart and Vascular Center, Houston, Texas, told theheart.org | Medscape Cardiology.
"If you judge by cases posted on Twitter, there is an increase in the number of operators performing it. We and others are using it routinely for persistent AF first ablations," said Valderrábano.
The VENUS Trial
Catheter ablation of persistent AF has limited success, with repeat procedures often needed. The vein of Marshall contains innervation and AF triggers that can be ablated by retrograde ethanol infusion.
The VENUS trial was conducted at 12 centers in the United States. The trial involved 343 patients (mean age, 66.5 years; 261 men) with symptomatic persistent AF (sustained AF lasting > 7 days) refractory to at least one antiarrhythmic drug.
Participants were randomly allocated to catheter ablation alone (n = 158) or catheter ablation combined with vein of Marshall ethanol infusion (n = 185). Vein of Marshall ethanol was successfully delivered in 155 of 185 patients (84%).
The primary outcome was freedom from AF or atrial tachycardia lasting more than 30 seconds after a single procedure without use of antiarrhythmic drugs on monitoring at 6 and 12 months.
This outcome was met by 49.2% of the vein of Marshall ethanol infusion group compared with 38.0% of those who did not receive the ethanol infusion, a statistically significant absolute difference of 11.2% (hazard ratio [HR], 0.63; 95% CI , 0.41 to 0.97; P = .04).
In terms of AF burden, a secondary outcome, this was zero at 6 and 12 months in 78.3% of the ethanol infusion group and 67.9% of the control group (P = .01).
Freedom from AF after multiple procedures (65.2% vs 53.8%; P = .04) and success achieving perimitral block (80.6% vs 51.3%; P < .001) were also significantly improved in vein of Marshall ethanol infusion patients.
"The vein of Marshall ethanol infusion procedure did not increase procedural complications. Adverse events were consistent with the overall aggressive ablation approach used in both groups," the investigators report in their article.
The main adverse event in the ethanol infusion group was fluid overload requiring diuretics, which occurred in 10 patients compared with two patients in the control group.
"Like any new technique, operators have to make an effort to learn it," Valderrábano told theheart.org | Medscape Cardiology.
"If you consider it as a variant of an angioplasty, it is an easy angioplasty, but most electrophysiologists don't routinely use angioplasty and it can be out of their comfort zone," he noted.
"Success of vein of Marshall procedure completion was 155/185 in the trial, but was significantly higher (> 90%) in the high-volume centers, suggesting that with experience you get better at it. Failures are most likely due to absence of a vein of Marshall," he explained.
The VENUS study was funded by a grant from the National Institutes of Health/National Heart, Lung, and Blood Institute, with additional support from Charles Burnett III and Lois and Carl Davis Centennial Chair endowments and Houston Methodist Research Institute. Valderrábano reported serving as a consultant for Biosense Webster; a speaker for Boston Scientific; research support member for Circa Scientific; and consultant and speaker for Baylis Medical.
JAMA. 2020;324(16):1620-1628. Abstract
Medscape Medical News © 2020
Cite this: Megan Brooks. VENUS: Vein of Marshall Ethanol Infusion for AF Now Published - Medscape - Nov 04, 2020.