Bidirectional ventricular tachycardia of unknown etiology

A 45 years old male presented to the emergency department with palpitations, headache and apprehension. Hiselectrocardiogram revealed bidirectional ventricular tachycardia. He remained vitally stable and responded to intravenous beta-blocker. Initially digitalis toxicity was suspected but history was negative for digitalis intake. The cause remained unidentified in patient despite detailed investigations. During a short follow-up [of 6 months] he remained asymptomatic and no cause was further identified during this period. Some other unseen causes of bidirectional ventricular tachycardia need to be explored