Coarctation and related aortic arch anomalies in hypoplastic left heart syndrome

The aortic arches of 34 specimens with hypoplastic left heart syndrome were studied in order to establish the frequency, the nature and the clinical implications of aortic arch anomalies. A localized aortic coarctation was present in 23 specimens. The coarcation was located preductally in 2 and paraductally in 21 cases. The degree of obstruction caused by the coarctation varied considerably. In only 6 cases (1 preductal and 5 paraductal) was the obstruction judged to be severe. One of these cases had an additional aneurysm of the aortic wall proximal to the coarctation. An aberrant relation of the ductus arteriosus and the aortic arch was found in 2 specimens without localized coarctation. In the remaining 9 specimens the aortic arch appeared normal. The aortic arch anomalies were mostly present in specimens with a severely hypoplastic ascending aorta. Clinicians, when preparing infants with hypoplastic left heart syndrome for surgical palliation, should always suspect associated aortic arch anomalies, especially when there is severe hypoplasia of the ascending aorta. Coarctation of the aorta will require additional surgical treatment.