Electrophysiological and electrocardiographic characteristics of ventricular arrhythmias successfully treated by coronary venous ethanol ablation

Background: Coronary venous ethanol ablation (CVEA) is increasingly used for the treatment of ventricular arrhythmias (VAs). Objective: This study aimed to characterize the features of VAs eliminated by CVEA. Methods: Consecutive patients who underwent CVEA were prospectively enrolled and classified as acute success or failure groups. Targeted veins were categorized as the first septal vein (S1), left ventricular annular vein (LVA), or anterior interventricular vein (AIV). Results: 42 patients (mean age 52.5 ± 14.3 years; 42.9% female) underwent CVEA; 29 (69.0%) achieved acute success. Ethanol was delivered via S1 in 16 patients, LVA in 8, and AIV in 5. In success cases, S1- and LVA-eliminated VAs exhibited similar right bundle branch block-like morphologies, whereas AIV-related VAs showed a left bundle branch block pattern with QS in leads V1-V2 and late precordial R-wave transition. During ethanol infusion, a transient "irritative" response in VA burden occurred in 44.8% of patients and was more frequently observed in successful cases. Complications were limited to transient bundle branch block in 4 of 42 (9.5%) and transient ST-T changes in 1 of 42 (2.4%), which resolved spontaneously after pausing/terminating ethanol infusion as needed. During follow-up, 4 patients experienced VA recurrences. One underwent repeat CVEA at the same target vein, and 3 were successfully managed with drug therapy. Conclusion: Successful CVEA from S1 and LVA yield similar electrocardiographic morphologies, whereas AIV-related VAs were characterized by QS in V1-V2 with late precordial transition. An irritative response during ethanol infusion may indicate effective ablation, and ethanol delivery from S1 or LVA may induce transient bundle branch block.