In 1957, Jervell and Lange-Nielsen reported a syndrome of congenital sensory deafness associated with a prolonged QT interval in four children of a Norwegian family.¹ The affected children had multiple syncopal episodes, and three died suddenly at the ages of four, five, and nine years. Since 1957, other examples of the long-QT syndrome associated with deafness (the Jervell and Lange-Nielsen syndrome) have been described.²–⁴ In all cases, the apparent mode of inheritance was autosomal recessive. This syndrome is rare (estimated incidence, 1.6 to 6 cases per million).² Affected persons are susceptible to recurrent syncope, and they have a high . . .