An arteriovenous fistula from an aberrant right subclavian artery to the superior caval vein in a congenitally myxoedematous adult.

A 52-year-old woman with congenital myxoedema presented with congestive heart failure and a continuous heart murmur. On cardiac catheterization, an aberrant right subclavian artery was found which supplied an arteriovenous malformation. Her heart failure, however, was secondary to concomitant severe aortic regurgitation which was clinically masked by the signs of the fistula. To our knowledge, a congenital arteriovenous malformation arising from an aberrant subclavian artery has not been reported in the adult.