Exercise-induced atrial and ventricular tachycardias in a patient with left ventricular noncompaction and normal ejection fraction.

We report a patient with ventricular and atrial tachycardias reproducibly induced during exercise testing. Atrial tachycardia, but no sustained ventricular tachycardia, was induced during electrophysiological study. Catecholaminergic polymorphic ventricular tachycardia was considered because of normal echocardiogram, family history of sudden death, and polymorphic appearance of some of the nonsustained ventricular tachycardia episodes. However, most episodes of ventricular tachycardia were monomorphic. Cardiac magnetic resonance diagnosed isolated left ventricular noncompaction.