Introduction
The vein of Marshall (VOM), which runs in the epicardial posterolateral left atrium toward the coronary sinus (CS), is a target structure for AF ablation. It crosses the epicardial aspect of the mitral isthmus (MI) and contains cardiac autonomic nervous system structures, hosts atrial fibrillation (AF) drivers. Ablation of the VOM is required for treating perimitral left atrial (LA) flutter (PMLAF).1–3 For these reasons, the VOM represents an interesting target for AF and PMLAF catheter ablation (CA). Ethanol infusion in the VOM (EIVM) is the most-used technique because it uses the VOM as a vascular access to myocardial tissue and provides direct damage to the atrial myocardium drained by the VOM.2,4,5
Adjunct EIVM has been shown to provide good long-term freedom from atrial tacchyarrhythmia (AT) after non-paroxysmal AF ablation and improves acute and mid-term success of PMLAF ablation by addressing epicardial connections at the MI.6–13 As opposed to radiofrequency (RF) ablation, which provides direct thermal injury to tissue, EIVM-created atrial scarring relies on a different mechanism.2 Acute EIVM-induced atrial scarring in the VOM region has been demonstrated 5,9,14,15, but little is known about the long-term EIVM effect and the persistence of acute EIVM-created lesions.
In this study, we assessed the durability of EIVM by comparing acute and late scar induced by EIVM in patients who underwent redo LA procedure.