Understanding Carotid Endarterectomy and Its Benefits and Risks

A Surgical Method of Reducing Stroke Risk

EEG Cap. Oli Scarff / Staff / Getty Images

Carotid endarterectomy is a surgical operation in which a plaque is removed from the carotid artery. Plaques are areas of fatty build-up in blood vessels. In the carotid artery, plaque can narrow the opening, reducing blood flow to the brain as well as increasing the risk of clots breaking off the plaque and traveling through the cerebral vessels to cause a stroke. This narrowing of the blood vessel is called stenosis.

How Common Is the Procedure?

Physicians have been doing carotid endarterectomy for a long time, and do them fairly frequently in major medical centers. The first CEA was done in 1953 by Dr. DeBakey in Houston, Texas. At the present time, over 100,000 carotid endarterectomies are performed every year in the United States.

What Happens During a Carotid Endarterectomy?

During a carotid endarterectomy, a surgeon opens the carotid artery and removes the plaque that has formed in its inner layer, known as the endothelium. .

The first step is to ensure the patient is made comfortable using general or local anesthesia. Some patients prefer local anesthesia so they can be awake and inform the surgeon if they feel anything they shouldn’t. This approach also allows the physician to test the patient’s neurological status by asking them to do things like squeeze their hand. Others would rather sleep through the procedure.

In this case, intraoperative electrophysiologic monitoring with techniques like electroencephalography (EEG) can be used to ensure continued brain function. No evidence has shown a difference in outcome between using local or general anesthesia in carotid endarterectomy.

After anesthesia is administered, the surgeon clamps the artery to keep it from bleeding during the procedure.

While the artery is clamped, the brain will depend on the carotid artery on the opposite side for its blood supply. An incision is made into the clamped artery, and the layer of tissue containing the plaque is stripped away. Once the plaque is removed, the surgeon stitches the artery back together, and the clamp is removed.

Who Should Have an Endarterectomy?

The risk of having a stroke is about 1 to 2 percent a year for people with carotid stenosis. The National Institute for Health and Clinical Excellence has recommended that patients with moderate to severe stenosis who have recently suffered from stroke or a transient ischemic attack have an endarterectomy within two weeks.

Large clinical trials have shown that if a patient is having symptoms, is expected to live for five or more years, and has a skilled surgeon with a less than 3 percent rate of complications, that patient would benefit from an endarterectomy.

The benefits are fewer for people without symptoms, but in severe cases a carotid endarterectomy may still be appropriate.

There is more debate among physicians about when to do an endarterectomy in people who are asymptomatic, especially as pharmacological management of these patients improves with time.

What Are the Contraindications to Carotid Endarterectomy?

Carotid endarterectomy should not be attempted if the internal carotid artery is completely obstructed. Though it may seem odd, there is no known benefit of opening a completely closed artery, perhaps because if the artery is closed, there is no way for bits of clot to break away from the plaque and travel up to the brain.

If there has already been a large stroke on the side of the brain supplied by the narrow artery, there is less benefit to having the procedure done. Most of the damage that could be done has already occurred, and the procedure could increase the risk of bleeding into the area affected by the stroke.

If the surgeon or anesthesiologist decides that someone has too many medical problems and would likely suffer a complication from the surgery, then the surgery shouldn’t go forward.

What Tests Are Usually Done Before a Carotid Endarterectomy?

Imaging of the blood vessels in the neck should be done to determine the severity and location of the plaque. There are a few different ways of visualizing the internal carotid artery. Duplex ultrasound uses sound waves to show how blood is flowing through the vessels. Traditional cerebral angiography involves injecting a contrast dye into blood vessels and looking at how it spreads through the vessels on x-ray. While this is considered a gold standard in vascular imaging, it is invasive, and very good images can also be done with a CT angiogram (CTA) or MR angiogram (MRA). If one way of looking at the vessels leads to ambiguous results, the doctor may order more than one test.

What Are the Possible Complications of Carotid Endarterectomy?

CEA can be associated with complications as serious as stroke or death due to the procedure, however the risk is relatively low. About 3 percent of patients without symptoms and 6 percent of patients with symptoms suffer these complications. That’s another reason why it’s important to be in good health for the surgery: At a cumulative stroke risk of 1 percent a year without surgery, it can take a few years for the benefits of the operation to have outweighed the risks. That said, the highest risk of having a stroke due to a narrow carotid artery is shortly after having a previous stroke, in which case a surgery should be recommended as soon as possible.

Hyperperfusion syndrome is another potentially dangerous side effect of carotid endarterectomy. When part of the brain has been deprived of blood flow for a long time, it may lose its ability to control how blood would normally flow through those blood vessels. When the blood flow suddenly increases after the narrowing is resolved, the brain’s inability to control that blood flow can result in swelling and diminished function, which may mimic a stroke.

Less severe complications of the procedure include damage to the hypoglossal nerve, which innervates the tongue, which can lead to tongue weakness on one side. And, as with any surgery, there is some risk of infection and bleeding.


Executive Committee for the Asymptomatic Carotid Atherosclerosis Study (ACAS). Endarterectomy for asymptomatic carotid artery stenosis. Jama. 1995;273:1421-1428.

Halliday A, Mansfield A, Marro J, Peto C, Peto R, Potter J, Thomas D. Prevention of disabling and fatal strokes by successful carotid endarterectomy in patients without recent neurological symptoms: randomised controlled trial. Lancet. 2004;363:1491-1502.

Sharon Swain, Claire Turner, Pippa Tyrrell, Anthony Rudd on behalf of the Guideline Development Group, Diagnosis and initial management of acute stroke and transient ischaemic attack: summary of NICE guidance, BMJ 2008;337:a786, doi:10.1136/bmj.a786 (Published 24 July 2008)

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