A left coronary artery arising from the right sinus of Valsalva is a rare congenital coronary anomaly. We report a case of a 5-year-old boy with an anomalous left coronary artery from the right sinus of Valsalva whose presenting sign was cardiac arrest. There is no reported instance of a child <9 years of age without other congenital cardiac defects having died suddenly with this coronary anomaly. The transthoracic echocardiogram demonstrated normal origins of the coronary arteries, but on autopsy, an anomalous origin of the left main coronary artery from the right sinus of Valsalva was found.