Presentation of Case A 42-year-old woman was admitted to the hospital under cardiopulmonary resuscitation. She was first seen in the clinic at the age of nine years because of infrequent nocturnal bouts of abdominal pain and vomiting of six months' duration. A murmur and “dropped beats” were noted, and she was referred to the Cardiac Clinic. There was a history of otitis media and sore throat, treated with penicillin. She had been delivered by cesarean section at eight months of gestation because of maternal renal disease and hypertension; she was not cyanotic at birth or thereafter. There was no history.