Ablation of Ventricular Tachycardia Arising from the Great Cardiac Vein - A Rare Cause of Coronary Artery Injury.

We herein report a case of coronary artery injury during epicardial ablation of ventricular tachycardia (VT), and describe an effective method to combat such an injury. A male patient presented with recurrent palpitations which was refractory to medications, with a history of clinically documented VT during the symptomatic episodes. The ablation procedure was performed at the great cardiac vein/anterior interventricular vein (GCV/AIV) junction, in part because pace mapping showed a 12/12 match, and activation map of VT demonstrated the earliest activation site at GCV/AIV junction. During the initial radiofrequency energy application at 18 watts at a flow rate of 17ml/min, there was ST elevation in the anterior leads. Coronary angiogram revealed damage to the left anterior descending artery due to heat penetration, which was immediately after the flow rate was increased to 25 ml/min and the ST elevation disappeared in the anterior leads.