Carotid endarterectomy is a surgical procedure that removes plaque buildup from the carotid arteries, the two major blood vessels on either side of your neck that supply blood to your brain. The surgery is one of the most effective ways to prevent stroke in people with significant narrowing of these arteries, reducing the five-year risk of stroke and death by roughly 15% compared to medication alone in patients with severe blockages.
Why the Carotid Arteries Matter
Your carotid arteries carry oxygen-rich blood from your heart to your brain. Over time, fatty deposits called plaque can accumulate along the inner walls of these arteries, a condition known as carotid artery stenosis. As plaque builds up, the artery narrows. This is dangerous for two reasons: it restricts blood flow to the brain, and pieces of plaque can break loose, travel to the brain, and block a smaller vessel there. Both scenarios can cause a stroke or a transient ischemic attack (TIA), sometimes called a mini-stroke.
Carotid endarterectomy physically removes that plaque, restoring normal blood flow and eliminating a major source of stroke risk.
Who Needs This Surgery
The decision depends on two factors: how severely narrowed the artery is and whether you’ve already had stroke symptoms. Clinical guidelines divide patients into two groups.
Symptomatic patients are those who have experienced a TIA or mild stroke within the past six months. Surgery is a proven benefit when the artery is 70% or more blocked. For blockages between 50% and 69%, there may still be a modest benefit, though the evidence is less definitive.
Asymptomatic patients have significant narrowing but no stroke symptoms yet. Guidelines recommend surgery plus medication over medication alone when the blockage exceeds 70%. Research from the Asymptomatic Carotid Atherosclerosis Study identified a clear benefit at 60% stenosis or greater, though the threshold for intervention is generally set higher in practice because the immediate surgical risk must be weighed against a future stroke that may never happen.
For the surgery to make sense in asymptomatic patients, the perioperative complication rate (stroke or death during or shortly after the procedure) needs to stay below 2%. For symptomatic patients, the threshold is below 6%. Above those numbers, the surgical risk starts to cancel out the long-term benefit.
How the Blockage Is Diagnosed
Most people first learn about a carotid blockage through a duplex ultrasound, a painless test that uses sound waves to measure blood flow velocity through the artery. Higher velocity means the blood is squeezing through a tighter space. A peak velocity of 270 cm/s or higher in the internal carotid artery indicates severe stenosis (70% to 99%), while no detectable flow signals a complete occlusion.
Magnetic resonance angiography (MRA) provides a more detailed picture and is often used alongside ultrasound. The traditional gold standard is digital subtraction angiography, which involves injecting contrast dye and taking X-rays, but this carries its own complication risk and is used less frequently now that noninvasive imaging has become highly accurate. Many surgical teams base their decision on a combination of ultrasound and MRA without needing the invasive test.
What Happens During the Procedure
The surgeon makes an incision along the front of your neck to access the carotid artery. Once the artery is exposed and blood flow is temporarily controlled, the surgeon opens the artery and carefully separates the plaque from the vessel wall. After the plaque is removed, the artery is closed with stitches or repaired using a patch graft, a small piece of vein or synthetic material that widens the artery slightly to prevent re-narrowing.
There is also an alternative technique called eversion endarterectomy. Instead of opening the artery in place, the surgeon cuts it, turns it inside out, strips the plaque away, and then reattaches the artery. Both methods accomplish the same goal. The entire operation typically takes about 110 minutes.
Risks and Complications
The primary risk of carotid endarterectomy is the very thing it’s designed to prevent: stroke. Manipulating a plaque-filled artery can dislodge debris during the procedure. In large studies involving tens of thousands of patients, the perioperative rate of stroke or death is about 1.7% overall. For asymptomatic patients specifically, the rate drops to around 1.1%, while symptomatic patients face a slightly higher risk of about 2.4%.
Cranial nerve injury is another recognized complication, occurring in roughly 2.5% of cases. The nerves that run near the carotid artery control tongue movement, vocal cord function, and facial sensation. Most of these injuries are temporary, causing hoarseness or difficulty swallowing that resolves over weeks to months. Bleeding, infection, and blood pressure instability in the hours after surgery are also possible but uncommon.
Alternatives to Surgery
Two less invasive options exist for patients who may not be ideal surgical candidates due to anatomy, prior neck surgery, or other medical conditions.
Transfemoral carotid artery stenting (TF-CAS) involves threading a catheter from the groin up to the carotid artery and placing a metal mesh stent to hold the artery open. It avoids a neck incision entirely but carries a higher perioperative stroke or death rate of 3.7%, roughly double that of endarterectomy. At one year, the gap remains: 9.7% for stenting versus 5.2% for endarterectomy.
Transcarotid artery revascularization (TCAR) is a newer hybrid approach. The surgeon makes a small incision at the base of the neck and temporarily reverses blood flow in the carotid artery to catch any debris before it reaches the brain, then places a stent. Its perioperative stroke or death rate is 2.0%, closer to endarterectomy’s 1.7%. TCAR also has a much lower rate of cranial nerve injury (0.2% versus 2.5%) and a shorter operative time of about 66 minutes. For symptomatic patients specifically, one large study found that TCAR had the lowest one-year likelihood of stroke or death among all three approaches.
The choice between these procedures depends on your anatomy, your symptoms, and the expertise available at your treatment center. Endarterectomy remains the most studied and widely performed option.
Recovery After Surgery
Most people spend one to two days in the hospital after carotid endarterectomy. During this time, your blood pressure is monitored closely because it can fluctuate in the first 24 hours. The neck incision is relatively small and typically heals well, though you may have some soreness, swelling, or numbness around the site.
You can start light everyday activities as soon as you feel ready. Most people return to their normal routine, including work, within three to four weeks. During recovery, you’ll likely be asked to avoid heavy lifting and strenuous exercise for a period. Long-term, the surgery doesn’t eliminate the underlying condition that caused plaque to build up in the first place, so managing blood pressure, cholesterol, and other cardiovascular risk factors with medication and lifestyle changes remains essential to keeping the artery clear.