To improve the prenatal diagnosis for anomalous origin of pulmonary artery branches by comparing and analyzing different types of fetal echocardiography features.

Between June 2012 and December 2018, fetal echocardiographic features were analyzed retrospectively from fetuses with a prenatal diagnosis of anomalous origin of pulmonary artery branch. The main points of identification were summarized.

A total of 12 fetuses were diagnosed, including anomalous origin of a pulmonary artery branch from the innominate artery and six cases with unilateral absence of pulmonary artery. The shared characteristic sonographic finding was the lack of confluence at the bifurcation of the main pulmonary artery. The differences between the two conditions are highlighted by the origin of the anomalous vessel. In fetuses with anomalous origin of one pulmonary artery branch, the affected pulmonary artery arose from the posterior wall of the ascending aorta as noted on three vessels and trachea view as well as the long axis of the left ventricular outflow tract. This is in contrast to fetuses with unilateral absence of pulmonary artery, where the origin of affected pulmonary artery arises from the base of the innominate artery via the ipsilateral patent arterial duct as evident on the three vessels and trachea view and the coronal view of innominate (brachiocephalic) artery.

(1) The main similarity is an absence of a confluence at the bifurcation of the main pulmonary artery. (2) The main distinguishing feature is the origin of the anomalous vessel from either the subclavian or directly from the aorta.