SUBCLAVIAN STEAL SYNDROME: A Review.

The Subclavian Steal Syndrome is a condition that results from the stenosis or occlusion of the subclavian artery proximal to the origin of the vertebral artery. The blockage causes the reversal of the normal direction of blood flow in the vertebral artery which is termed the "steal", because it steals blood from the cerebral circulation. Blood is drawn from the contralateral vertebral, basilar or carotid artery regions into the low-pressure ipsilateral upper limb vessels. Although a relatively uncommon disease, it represents a condition which mimics many conditions often treated by chiropractors and osteopaths. The term subclavian steal syndrome is applied when reversed vertebral artery flow causes cerebral ischaemia with associated symptoms of vertebrobasilar hypoperfusion and/or symptoms of brainstem or arm ischaemia. This syndrome exists as an important consideration in the differential diagnosis of cerebral and brachial ischaemia.