An incessant ventricular tachycardia arising from the posterior fascicle is reported in a 29-year-old woman. This fascicular tachycardia was due to triggered activity and was clinically induced by an underlying paroxysmal atrial fibrillation. The initial echocardiographic evaluation revealed biventricular dysfunction with an ejection fraction of 30%. On propranolol, the patient has remained asymptomatic and the ventricular function has become normal after 3 months free of arrhythmia.