We report the case of a 21 year-old patient with arrhythmogenic right ventricular dysplasia manifested by episodes of QRS tachycardia greater than 0.12 sec and isolated dysfunction of the right ventricle. The patient treated with amiodarone however, the tachycardia episodes persisted. The surface electrocardiogram showed left branch block with the axis down, which suggested a right ventricle origin, and was therefore considered an arrhythmogenic dysplasia. Echocardiography and cardioangiography showed alterations in the anatomy of the outflow tract of the right ventricle. A myocardial gammagraphy revealed no perfusion alterations. The endomyocardial biopsy showed perivascular fibrosis. An electrophysiology study was performed, stimulating the outflow tract of the right ventricle, which induced two types of ventricular tachycardias, one of them identical to that recorded clinical. The patient was treated with sotalol, and has been being free of ventricular tachycardia episodes for 18 months of follow-up. We consider that this entity should be studied in a systematic way in those patients with ventricular tachycardia originated in the outflow of the right ventricle and with primary cardiac illness.