Long Q-T syndrome: a preventable form of sudden death.

The long Q-T syndrome, with or without congenital deafness, is characterized by syncopal attacks and prolongation of Q-T interval on the electrocardiogram. Untreated cases with syncope are usually fatal, but if diagnosed and treated appropriately with beta adrenergic blockers or surgical left stellate ganglionectomy, prognosis is markedly improved. This report describes an 11-year follow-up of a child with the long Q-T syndrome, in whom frequent syncopal attacks were successfully treated with propranolol.