Radiofrequency catheter ablation of ventricular tachycardia from the anterobasal left ventricle

Ventricular tachycardia (VT) in coronary artery disease arises mostly from endocardial sites. However, little is known about the site of origin in oth er diseases. We report two patients who had VT originating from an anterior aspect of the left ventricle just below the mitral annulus, adjacent to th e left ventricular outflow tract. The QRS configuration of VT showed an inf erior axis and monophasic R waves in all the precordial leads. Radiofrequen cy current delivered to this site from the endocardial site successfully ab lated the tachycardia in both.