Prenatal ultrasonic diagnosis and differential diagnosis of isolated right aortic arch with mirror-image branching.

Abstract

This study sought to evaluate the fetal echocardiography features of isolated right aortic arch (RAA) with mirror-image branching and to improve the rate and accuracy of prenatal diagnosis of this condition. We reviewed fetal echocardiograms from all cases of isolated RAA with mirror-image branching diagnosed at our institution between August 2012 and December 2015 and classified these cases into normal and abnormal types of ductus arteriosus based on the course of the arterial duct arch. We confirmed the diagnoses by postnatal echocardiography. A total of 11 cases of isolated RAA with mirror-image branching, with the left ductus and the descending aorta located on the left side of the spine, were diagnosed using fetal echocardiography. Ten cases involved normal ductus arteriosus, with the left ductus connecting the left pulmonary artery to the descending aorta, five of which were referred to our institution for suspicions of double aortic aorta. 1 case involved abnormal ductus arteriosus, with the left ductus connecting the left pulmonary artery to the left innominate artery. RAA with mirror-image branching can be detected via fetal echocardiography, which can reveal the relationship between of the aortic arch and the trachea and can enable the identification of the course of brachiocephalic branching. The identification of isolated RAA with mirror-image branching is crucial for distinguishing this condition from other types of aortic arch anomalies, particularly double aortic aorta, which can have a rather different prognosis.