Fetal echocardiographic diagnosis of a triad with common embryological origins: Cervical aortic arch, retro-aortic left innominate vein and coarctation of the aorta

Cervical aortic arch (CAA) and retro-aortic innominate vein (RAIV) are rare entities which can be associated with one another in a structurally normal heart. Less well recognized is the fact, that a third entity may often be present as well, since aortic arch abnormalities are common in a CAA. Hence, these three entities (CAA, RAIV, and an arch anomaly - in this case a post-ductal coarctation) may present as a triad. We present the first prenatal diagnosis of this rare triad which can be explained by common embryological origins which are discussed along with instructive aspects in diagnosis and management.