Clinical outcomes of venous ethanol ablation with and without the catheter guidance in the endocardium. (A) Schematic of the catheter utilization in two groups. The branch closest to the catheter was apparent and proven to be the target vein with guidewire mapping. (B) The catheter guidance group demonstrated higher success rate, shorter procedural time, and less fluoroscopy exposure. Data are expressed as the percentage or median with interquartile (Q1, Q3). CG, catheter guidance; non-CG, non-catheter guidance; GCV/AIV, great cardiac vein/anterior interventricular vein; RVOT, right ventricular outflow tract.