Dilatation of the descending aorta: a radiologic and echocardiographic diagnostic sign in arteriovenous malformations in neonates and young infants.

Eleven infants with arteriovenous malformations were admitted to St. Christopher's Hospital for Children between 1970 and 1978. Dilatation of the descending aorta was seen in the chest roentgenogram in 8 of the 11 patients. Echocardiography used in the two most recent cases revealed approximation of the descending aorta to the posterior left atrial and left ventricular wall in association with generalized cardiomegaly. The most frequently reported radiologic findings in infants with arteriovenous malformations are cardiomegaly, increased pulmonary vasculature and a widened superior mediastinum. These findings can accompany other congenital malformations of the heart, but the radiographic and echocardiographic findings of a dilated descending aorta appear to be more specifically associated with arteriovenous malformations in the neonate and infant.