Subclavian Steal Syndrome

Subclavian steal syndrome is caused by severe stenosis or occlusion of the proximal subclavian artery, which leads to reversed flow in the ipsilateral vertebral artery so that blood is 'stolen' to supply the arm. Atherosclerosis is by far the most common cause; Takayasu arteritis and trauma are less frequent.

When demand increases during arm activity, blood is drawn from the brainstem via the vertebral artery toward the arm, producing symptoms of vertebrobasilar ischemia. Diagnosis is usually made from an interarm blood pressure and pulse difference, duplex ultrasound and angiography.

Treatment is percutaneous subclavian angioplasty with stenting or carotid-subclavian bypass. Risk factor control is important for managing coexisting coronary and peripheral disease.