[Idiopathic sustained ventricular tachycardia in the young adult with right bundle-branch and left axis deviation]

The authors report 4 cases of sustained ventricular tachycardia with right bundle branch block and left axis deviation morphology. These ventricular tachycardias which are usually sensitive to Verapamil are often mistaken for supraventricular tachycardia. However, they are a specific clinical, electrocardiographic and electrophysiological entity. The origin of the tachycardia is probably in the Purkinje fibres of the left posterior hemibranch of the His bundle. The mechanism is controversial: much evidence points to reentrant phenomenon, but, in the present state of our knowledge, triggered activity cannot be formally excluded.