Two-dimensional echocardiography in infants with persistent truncus arteriosus.

Two-dimensional echocardiography was used to study a consecutive series of 13 infants with persistent truncus arteriosus. In all a single great artery with the long upward course characteristic of the aorta was shown. This great artery could be identified as a persistent truncus arteriosus by the recognition of a branch arising from its ascending part (10 out of 13) or of more than three semilunar valve cusps (5/13). These criteria allowed the correct diagnosis to be reached in 12 of the 13 infants.