Interruption of aortic arch type A in two siblings.

The recurrence of interruption of aortic arch (IAA) in siblings is rare. According to previous reports concerning siblings with IAA, all cases were IAA type B according to the classification proposed by Celoria and Patton. In this report we present the first cases of brothers with IAA type A. The type of IAA was confirmed by autopsy findings in the elder brother and by operative findings in the younger brother. The etiology of IAA was unclear. Monogenic inheritance was thought unlikely because congenital heart disease was not recognized in other members of the family. It would seem prudent to separate recurrence risks for IAA type A from IAA type B when genetic counselling is provided, but it must be borne in mind that the recurrence of IAA type A can occur among siblings.