Complex Congenital Heart Malformation Including Transposition of the Great Vessels, Presenting as Sudden Unexplained Infant Death.

Transposition of the great vessels (TGV) is a common congenital heart defect that is difficult to diagnose before birth. Antenatal diagnosis is associated with increased survival. Unusual features such as anomalous pulmonary artery origin may delay cyanosis, decreasing clinical suspicion. A three-week old female infant who had never been cyanotic presented for forensic autopsy due to onset of unresponsiveness at home. History included risk factors for TGV and signs of heart enlargement that were not recognized during life. Cardiac pathology consultation identified D-type TGV with additional rare anomalies. TGV may present as sudden unexplained infant death (SUID) for forensic autopsy if variant features prevent development of cyanosis. Cardiac pathology consultation is helpful in clarifying these features.