Bhuiyan et al. (2007) studied a large consanguineous family of Sudanese origin in which 3 sibs died suddenly during physical activity. The first death occurred in a 10-year-old girl who died while playing in a fun park; no ... Bhuiyan et al. (2007) studied a large consanguineous family of Sudanese origin in which 3 sibs died suddenly during physical activity. The first death occurred in a 10-year-old girl who died while playing in a fun park; no evaluation was performed. The second death involved her younger brother, who collapsed at 12 years of age while skating; during resuscitation he was noted to have several episodes of ventricular tachycardia. Electrocardiography (ECG) revealed a mildly prolonged QTc (450 to 490 ms) and premature ventricular contractions (PVCs) with a right bundle branch block (RBBB) morphology and superior axis, indicating a left ventricular origin. ECG showed no structural cardiac anomaly. He remained in a vegetative state until his death from pneumonia 2 years later. The third sib was a younger sister who underwent palliative surgery for tetralogy of Fallot in infancy, at which time ECG revealed a QTc of 440 ms; ECG at 14 months of age showed QTc of 480 to 490 ms. After corrective cardiac surgery at 3 years of age, ECG showed RBBB with QRS duration of 110 ms and uncorrected QTc of 470 to 490 ms. She collapsed and died while playing sports at 8 years of age. A 7-year-old male cousin, also born of consanguineous parents, was the only surviving patient. ECG after a syncopal episode while playing outdoors showed borderline prolonged QTc of 480 ms; echocardiogram was normal. Exercise stress testing revealed isolated PVCs at a heart rate of 144 bpm, with couplets appearing at a heart rate of 170 bpm after exercising for 6 minutes, at which time the test was terminated. He was put on a beta-blocker and restricted from exercise and was still alive at follow-up 18 months later. The parents were all asymptomatic, and the parents of the surviving patient had normal ECGs; 3 asymptomatic sibs of the deceased sibs had no PVCs on 24-hour ECG monitoring.