Antenatal sonographic findings associated with scimitar syndrome.

Scimitar syndrome is a rare congenital anomaly that consists of secondary dextroposition in situs solitus, due to right pulmonary hypoplasia. The prenatal sonographic findings of this abnormality have not been previously described. We describe early sonographic findings in a fetus that included isolated cardiac dextroposition with normal abdominal situs, hydramnios and mild narrowing of the right pulmonary artery. Postnatally, the infant developed heart failure, and a right hypoplastic lung was found. Catheterization revealed collateral supply to the right lung arising from the descending aorta and anomalous drainage of right pulmonary veins to the inferior vena cava. The diagnosis of scimitar syndrome was therefore established. A coil embolization of arterial collaterals to the right lung was performed. Scimitar syndrome should be considered in a fetus with the sonographic findings of a right shift of the mediastinal structures, an intact diaphragm and narrow right pulmonary artery. This may allow early neonatal stabilization and treatment.