Isolated coarctation of the aorta in the fetus: A diagnostic challenge.

Isolated coarctation of the aorta (CoA) is estimated by the Centers for Disease Control and Prevention to account for 4%-6% of all congenital heart disease (CHD) in the United States, with a reported prevalence of ~4 per 10 000 live births. Prenatal recognition of coarctation is important as it may improve neonatal survival and reduce morbidity. However, despite advances in imaging and the trend toward detailed aortic arch assessment as part of a comprehensive fetal echocardiogram, isolated CoA may still elude prenatal detection, with potentially lethal consequences if the diagnosis is not suspected and the patent ductus arteriosus (PDA) closes spontaneously in postnatal life. The purpose of this review is to outline the methods of antenatal aortic arch evaluation in the current era, discuss "red flags" that raise the suspicion for CoA, including associated anomalies and serve as a repository of the most up to date information regarding its diagnosis in utero and its perinatal management. Other aortic arch abnormalities, such as interrupted aortic arch, or CoA associated with complex single ventricles, are not included in this review.