Last updated: 11/24/2009

The presence of fatty deposits in the carotid arteries of the neck is the most significant risk factor for ischemic stroke, which represents 80% of all strokes. A stroke can be either ischemic, which is an interruption of blood flow in a narrowed carotid...

artery, or hemorrhagic, which involves bleeding in the brain. Carotid endarterectomy is performed as prevention of ischemic strokes.

Some people at high risk for ischemic stroke have disturbing symptoms that can occur periodically and last from minutes to up to 24 hours, and then disappear. These episodes are called transient ischemic attacks (TIA). The symptoms are the same as actual stroke symptoms. The symptoms of TIA and ischemic stroke may include:

• Numbness, muscle weakness, or paralysis of the face, arm, or leg, usually on one side of the body, and usually occurring suddenly.
• speech or vision difficulties
• sudden loss of understanding, confusion
• lightheadedness or fainting spells
• loss of balance with difficulty walking and moving; poor coordination
• severe headache with no obvious cause, either sudden or persistent

About 35% of people who have TIAs will have a stroke within five years. The risk of stroke goes up with age and is greatest in people whose blood pressure is higher than normal. High blood pressure stresses the walls of blood vessels, particularly when the vessels are blocked with plaque and so space for blood to pass is reduced.

Carotid endarterectomy has been performed since the 1950s as a stroke-prevention method. During the 1990s, about 130,000 carotid endarterectomies were performed each year in the United States. Because the surgery itself presents a high risk of complications, surgeons will look at the possible benefits and risks for each patient and compare them with such medical treatment as drug therapy to reduce plaque, cholesterol, and blood pressure. Carotid endarterectomy is typically performed on those who will benefit most from the surgery and who have the lowest risk for postoperative complications. Good candidates include:

• People who have already had one or more TIA episodes in a six-month period, with 70% narrowing of the carotid arteries supplying the part of the brain affected by the TIA.
• People who have had a mild stroke in the past six months but who are not significantly disabled and whose carotid arteries are at least 70% narrowed.
• People who have not had a stroke or TIA, but their carotid arteries are narrowed 60% or more and they have low risk of complication from having the surgery.

Carotid endarterectomy is not recommended for:

• People whose risk of complications from the surgery is greater than the intended benefits. The presence of other problems such as heart disease may increase risk.
• People who have had a TIA but their carotid arteries are less than 50% narrowed.
• People who have had a stroke or TIA because arteries other than the carotid arteries are blocked.
• People whose carotid arteries are blocked above a point on the neck where they can be reached easily during surgery.

The endarterectomy procedure takes about an hour to perform. General anesthesia is usually administered. A vascular surgeon or neurosurgeon will usually perform the surgery. During the procedure, a small incision is made in the neck below the jaw to expose the carotid artery. Blood that normally flows through the artery must be diverted in order to perform the surgery. This is accomplished by rerouting the blood through a tube (shunt) connecting the vessels below and above the surgical site. The carotid artery is opened and the waxy fat deposit is removed, sometimes in one piece. If the carotid artery is observed to be too narrow or too damaged to perform the critical job of delivering blood to the brain, a graft using a vein from the patient's leg may be created and stitched (grafted) onto the artery to enlarge or repair it. The shunt is then removed, and incisions in the blood vessels, the carotid artery, and the skin are closed.