Symptomatic Extracranial Large Artery Disease

We discuss diseases of the carotid, vertebral, and subclavian arteries that may cause stroke. Most large artery disease is atherosclerotic, but we also consider dissection and vasculitis, and issues of therapy. Subclavian stenosis or occlusion may cause vertebrobasilar ischemia by stealing blood from the posterior circulation; it may also result in “Pseudonormotension”: normal blood pressure measured by cuff in the brachial artery, with severe systemic hypertension detected by intra-arterial measurement of femoral blood pressure. Acute/subacute arteritis such as giant cell arteritis would usually be treated with corticosteroids and other immunosuppressive agents, but consideration might be given to the use of colchicine in radiation arteritis, which is chronic. Periprocedural risks of carotid endarterectomy versus stenting are clearly related to age. With some exceptions, old patients will generally be better served by endarterectomy, whereas younger patients would benefit more from stenting. Vertebral artery injury at the C1-2 level from chiropractic manipulation, motor vehicle collisions, and other neck injuries is probably under-recognized as a cause of stroke, particularly when it results from motor vehicle collisions. The concept of “white thrombus” (formed in fast flow) versus “red thrombus” (formed in stasis) is important in choosing between antiplatelet therapy and anticoagulants for patients with dissection.