Epicardial scar in a patient with no apparent heart disease

A 35-year-old man, who had an episode of aborted sudden cardiac death due to ventricular fibrillation, suffered from multiple storms of ventricular tachycardia (VT). Conventional cardiac examinations did not reveal any structural heart diseases, and he had been treated by an implantable cardioverter defibrillator since 2007. At the latest admission, epicardial but not endocardial voltage mapping revealed a small area of low voltage at the left ventricular (LV) postero-lateral wall where a delayed potential was recorded during sinus rhythm. Excellent pacemapping with a prolonged stimulus to QRS interval was obtained from the area, and a mid-diastolic potential was recorded during the VT. Radiofrequency application terminated the VT and any VT became noninducible after the ablation. In some patients diagnosed as LV-VT with no apparent heart disease, arrhythmogenic substrate may exist on the epicardial surface of the ventricle.