Vertebral Grand Larceny.

THE "subelavian steal" is a clinical syndrome that has been described only recently.1-10 Patients so afflicted are usually elderly, with an atherosclerotic plaque blocking the left subclavian artery between the aortic arch and the origin of the left vertebral artery. The left vertebral artery carries blood in retrograde fashion, siphoning part of the brain's supply from the circle of Willis to fulfill the demands of the left arm. With the stimulus of exercise of the left arm, these patients may become syncopal. This syndrome focuses attention on the vertebral arterial confluence as a collateral pathway in patients with peripheral vascular disease. An infant in whom retrograde flow of the left vertebral artery supplied blood to the left arm, the trunk, and the lower extremities, and to some extent the lungs, made us aware of the possible importance of this pathway in patients with congenital obstructive lesions of the aortic arch.