Hypoplastic right retro-oesophageal aortic arch: similarities to interrupted aortic arch.

At echocardiography a dysmorphic neonate was found to have a hypoplastic mitral valve, left ventricle, and ascending aorta with interruption of the aortic arch between the left common carotid and the left subclavian arteries--the left subclavian artery arose from a normal sized left descending aorta. Cardiac catheterisation and subsequent necropsy confirmed this arrangement but also showed a tortuous right retro-oesophageal aortic arch. This arch was severely hypoplastic distal to the right subclavian artery. These cardiovascular anomalies occurred in the child of a family in which other members showed the velo-cardio-facial syndrome, a condition known to be associated with right aortic arch. This aortic arch arrangement may be impossible to distinguish from simple aortic interruption by echocardiography alone.