What is carotid artery stenosis or carotid artery disease?

Carotid artery stenosis is the narrowing of the carotid arteries. These are the main arteries in the neck that supply blood to the brain. Carotid artery stenosis, also called carotid artery disease, is a major risk factor for ischemic stroke. (This is the most common form of stroke and is usually caused by a blood clot plugging an artery.)

The narrowing is usually caused by plaque in a blood vessel. Plaque forms when cholesterol, fat and other substances build up in the inner lining of an artery. This process is called atherosclerosis.

How is carotid artery stenosis diagnosed?

Carotid artery stenosis may or may not cause symptoms. A doctor may hear an abnormal sound called a bruit (BROO'e) when listening to the artery with a stethoscope. The stenosis can be easily detected with an ultrasound probe placed on the side of the neck near the carotid arteries. This is called carotid ultrasonography.

How is carotid artery stenosis treated?

Depending on the degree of stenosis and the patient's overall condition, carotid artery stenosis can usually be treated with surgery. The procedure is called carotid endarterectomy. It removes the plaque that caused the carotid artery to narrow. Carotid endarterectomy has proven to benefit patients with arteries stenosed (narrowed) by 70 percent or more. For people with arteries narrowed less than 50 percent, anti-clotting medicine is usually prescribed to reduce the risk of ischemic stroke. Examples of these drugs are antiplatelet agents and anticoagulants.

Carotid angioplasty may be another treatment option. It uses balloons and/or stents to open a narrowed artery. 

For stroke information, call the American Stroke Association at 1-888-4-STROKE. 

Related AHA and ASA publications:

• Heart and Stroke Facts
• Stroke: Are You at Risk? (also in Spanish on ASA Web site)
• Know the Facts... Get the Stats
• Understanding Stroke (also in Spanish)

Related AHA scientific statements:
Angioplasty
Stroke