Cerebral ischemia due to congenital malformations of brachiocephalic arteries--case reports.

Seven cases of congenital anomalies of brachiocephalic arteries are presented; malformations include unilateral absence of the internal carotid artery (ICA) (n = 3), unilateral hypoplasia of the ICA (n = 2), agenesis of the innominate artery (n = 1), and atresia of the subclavian artery (n = 1). All patients but 1 exhibited symptoms of cerebrovascular insufficiency at the time of radiologic investigation; they were not affected by other cardiovascular malformations, except right aortic arch in 2 cases and left cervical arch in another case. Two patients suffering from congenital subclavian steal syndrome underwent surgery to correct the vascular malformations. Embryogenesis and natural history of such malformations are briefly discussed.