Postablation Peri-Mitral Flutter Terminated by Vein of Marshall Ethanol Infusion and Extra Epicardial Ablation

Ethanol infusion into the vein of Marshall (EIVOM), combined with radiofrequency catheter ablation, has been shown to facilitate atrial fibrillation management and achieve bidirectional mitral isthmus (MI) block. However, the anatomic variations of vein of Marshall (VOM) may influence procedural efficacy and should be considered.

A 59-year-old man with persistent atrial fibrillation underwent radiofrequency catheter ablation with the 2C3L (pulmonary vein isolation and linear ablations across the mitral isthmus, left atrial rooftop, and cavotricuspid isthmus) strategy. Despite adequate endocardial ablation and conventional epicardial ablation via the coronary sinus, recurrent peri-mitral flutter developed. EIVOM was subsequently attempted to reinforce the MI block but proved insufficient. Finally, targeted intracoronary sinus epicardial ablation at the proximal VOM terminated the flutter and achieved durable bidirectional block.

Although EIVOM has proven value in facilitating MI block, its anatomy-dependent efficacy necessitates comprehensive consideration evaluation in clinical practice.

The effectiveness of EIVOM depends on VOM anatomy, and meticulous extra epicardial ablation may be required to achieve complete MI block.