Fetal sonographic diagnosis of aortic arch anomalies

TLDR

Aortic arch anomalies are congenital malformations of the arch’s position or branching pattern, and while they are relatively common, prenatal detection remains uncommon. The study seeks to refine the fetal aortic arch model to enhance understanding of congenital arch anomalies. A systematic sonographic protocol is presented that identifies the trachea, three major vessels, ductus arteriosus, and descending aorta in axial views, noting abnormal descending aorta position, loss of the V‑shaped ductal‑aortic confluence, gaps between the ascending aorta and main pulmonary artery, and vessels behind the trachea as key diagnostic clues. Precise assessment of these landmarks allows reliable prenatal diagnosis of vascular rings, enabling timely postnatal management.

Abstract

Aortic arch anomalies refer to congenital abnormalities of the position or branching pattern, or both of the aortic arch. Although aortic arch anomalies are not uncommon, reports on their prenatal diagnosis are scarce. Insight into the hypothetical arch model is crucial to understanding anomalies of the aortic arch in the fetus. Recognition of the trachea, three major vessels, ductus arteriosus and descending aorta in the axial views of the upper mediastinum is necessary for a complete fetal cardiac assessment. Clues to aortic arch anomalies include abnormal position of the descending aorta, absence of the normal 'V'-shaped confluence of the ductal and aortic arches, a gap between the ascending aorta and main pulmonary artery in the three-vessel view, and an abnormal vessel behind the trachea with or without a vascular loop or ring around the trachea. Meticulous attention to anatomic landmarks will lead to successful prenatal diagnosis of important vascular rings making early postnatal management possible.