'Bradycardia-tachycardia' syndrome 8 yr after correction of Fallot's tetralogy.

A 13-yr-old boy presented with atrial flutter 8 yr after surgical correction of tetralogy of Fallot; antiarrhythmic therapy caused depression of the sinoatrial node, with syncope. Disordered sinoatrial function and intraventricular conduction were demonstrated by intracardiac electrography, and appear to have resulted from the operation. Sinoatrial disease may be responsible for supraventricular arrhythmias or syncope long after operative correction of Fallot's tetralogy and may be one of the explanations for the tendency of such patients to die suddenly.