Carotid Artery Stenosis

Carotid artery stenosis is a condition where the large arteries in your neck become narrowed by a buildup of fatty deposits called plaque, putting you at higher risk of stroke—one of the leading causes of death and disability worldwide.

Table of contents

• What is carotid artery stenosis?
• Causes and risk factors
• Symptoms and warning signs
• How is it diagnosed?
• Treatment options
• Lifestyle changes and prevention

What is carotid artery stenosis?

Carotid artery stenosis is a condition that happens when your carotid arteries, the large blood vessels on either side of your neck, become blocked or narrowed^[1]. You have two carotid arteries—one on each side of your neck. These arteries are responsible for bringing blood to your brain, face, and head^[1].

• Carotid arteries (neck)
• Brain
• Face
• Head

When these arteries are healthy, they are smooth and open, like a clean pipe that allows fluid to flow freely without anything in the way^[1]. The blockage is made up of a substance called plaque, which consists of fatty cholesterol deposits^[1]. This buildup of plaque is called atherosclerosis^[1].

You can develop carotid artery stenosis in either of the two arteries in your neck or in both^[1]. As plaque enlarges, it begins to narrow the inside opening of your carotid artery where blood flows. This changes how easily blood can flow and can increase the risk of developing a blood clot inside the vessel^[9].

The prevalence of carotid artery stenosis in the general population is estimated to be as high as 5%^[1]. This condition usually happens over time and as you age. The risk for this condition as well as for stroke increases with age^[1].

Carotid artery disease, carotid stenosis

Causes and risk factors

Carotid stenosis is typically a chronic condition that affects people as they age. It occurs when excess cholesterol in the blood begins to change the blood vessel. The body sends inflammatory cells to help, and low density lipoprotein (LDL) cholesterol becomes heavily involved in this process. After a while, the LDL cholesterol begins to get trapped inside and eventually sticks to the outside of the blood vessel. Over time, this process continues and plaque forms^[9].

There are several factors that can increase your chance of developing this condition over time^[1]:

• Smoking and using tobacco products
• Having obesity
• Sedentary lifestyle (lack of physical activity)
• High blood pressure (hypertension)
• High cholesterol
• Diabetes
• Age

Some patients who have had radiation treatment for head and neck cancers can develop carotid artery stenosis from the radiation effect and not actually from plaque development^[9]. There are also some inflammatory conditions that can cause irregularities in the carotid arteries^[9].

Symptoms and warning signs

Many people with carotid artery stenosis do not experience any symptoms^[9]. It is often found by accident^[9]. If you have carotid artery stenosis that hasn’t caused a stroke, you may not notice any symptoms^[1].

However, this condition can lead to serious complications. Carotid artery stenosis can cause a stroke. The kind of stroke that usually happens from carotid stenosis occurs when pieces of plaque or blood clots that form on plaque travel to your brain^[1]. Called an ischemic stroke, it cuts off blood supply to a portion of your brain. When this blockage is permanent, your brain cells or neurons start to die^[1].

A transient ischemic attack (TIA) is a “mini-stroke” that’s only a temporary blockage of a small brain artery from plaque and/or platelets^[1]. For many people, a TIA comes before an ischemic stroke. A TIA is similar to a stroke but does not cause permanent damage to the brain and cannot be found on an MRI or CT scan^[9]. It is very important to seek treatment as quickly as possible for these conditions in order to prevent cell death^[1].

The symptoms of a TIA or stroke can include^[1][5]:

• Drooping of one side of your face
• Slurred speech or trouble forming words and communicating with others
• Losing vision in one eye with the experience of a dark shade coming down over your field of vision
• Losing feeling on one side of your body
• Losing muscle strength and having weakness on one side of your body
• Sudden numbness or weakness in the face or limbs, often on one side of the body
• Sudden trouble seeing in one or both eyes
• Sudden dizziness or loss of balance
• Sudden, severe headache with no known cause

The side of your body that the symptoms affect is a very important detail. For example, symptoms on one side of the body can indicate which carotid artery is affected^[9].

How is it diagnosed?

Carotid artery stenosis is often diagnosed after you’ve experienced symptoms of a stroke. The symptoms prompt your healthcare provider to thoroughly check for any type of blockage, which can lead to a discovery of carotid artery stenosis^[1].

Diagnosis usually starts with a medical history and physical exam. The exam generally includes listening for a swooshing sound, known as bruit, over the carotid artery in the neck. A narrowed artery causes this sound^[7]. The next step might be a test of physical and mental abilities such as strength, memory, and speech^[7].

Several imaging tests can be used to diagnose, locate, and measure stenosis^[4]:

• Carotid ultrasound (including Doppler ultrasound): This test uses sound waves to create real-time pictures of the arteries and locate blockages. Doppler is a special ultrasound technique that can detect areas of restricted blood flow in the artery^[4].
• Computed tomography angiography (CTA): CTA uses a CT scanner to produce detailed views of the arteries in the neck. The test is particularly useful for patients with pacemakers or stents^[4]. CT and MRI can show if you’ve had a stroke or other issues^[7].
• Magnetic resonance angiography (MRA): This noninvasive test gives information similar to that of CTA without using ionizing radiation^[4]. MRA gives more information about blood flow in the carotid arteries. These scans make images of the neck and brain after a contrast dye is put into a blood vessel. The dye makes areas of the images stand out^[7].
• Cerebral angiography: Also known as intra-arterial digital subtraction angiography (IADSA), this is a minimally invasive test in which a catheter is guided through an artery in the groin to the area of interest in the brain. Contrast material is injected through the tube and images are captured with X-rays^[4]. If other tests cannot determine the cause of your symptoms and carotid artery disease is suspected, you may need this more invasive test^[7].

Treatment options

Treatment for carotid artery stenosis depends on how severe the blockage is and whether you have symptoms. Treatment options range from lifestyle changes and medications to surgical procedures.

Medications

If blockage is mild to moderate, lifestyle modification and certain medications may be recommended to slow the progression of atherosclerosis^[4]:

• Blood-thinning medicines: Such as aspirin or clopidogrel, these decrease the chance of blood clots forming and help lower your risk of stroke^[4][15]. Aspirin irreversibly blocks the cyclooxygenase of platelets, thus inhibiting platelet synthesis^[11].
• Cholesterol medicines (statins): These help your liver produce less cholesterol. This prevents plaque from building up in the carotid arteries^[15]. Statins lower LDL cholesterol levels and are recommended for all patients with carotid atherosclerotic disease, with a target LDL level below 100 mg/dL^[11].
• Blood pressure medicines: These relax your blood vessels, make your heart beat slower, and help your body get rid of extra fluid. This helps lower high blood pressure^[15].

These medicines can have side effects. If you notice side effects, be sure to tell your doctor. Your doctor may change the dose or type of medicine you take to help reduce side effects. Never stop taking medicines or take less medicine without talking to your provider first^[15].

Surgical and interventional procedures

If blockage is severe, surgical treatment may be recommended^[4]:

• Carotid endarterectomy (CEA): This is the standard surgical treatment for many patients with severe or symptomatic carotid stenosis^[13]. A surgeon makes an incision to remove plaque and any diseased portion of the artery while the patient is under general anesthesia^[4]. Studies have shown that symptomatic patients with 70-99% stenosis have clear benefit from this procedure. The incidence of stroke in 2 years was 9% with surgery compared to 26% with medical management alone^[11].
• Carotid artery angioplasty and stenting: A less invasive option used for severe stenosis. During this procedure, the doctor threads a catheter from an incision in the groin to the site of the blockage. Once there, they inflate a balloon tip to open the artery. The doctor may place a stent in the artery to expand it and hold it open^[4].
• Transcarotid artery revascularization (TCAR): This is a newer, less invasive, clinically proven treatment option. The procedure begins with a small incision just above the collarbone. A temporary sheath is placed directly into the carotid artery, and a blood flow reversal system decreases the risk of stroke. A stent is then inserted through the sheath to open the diseased carotid artery^[13]. When compared to traditional open surgery, patients undergoing TCAR usually recover quickly with less pain and smaller scars, and have a lower risk of cardiac complications and cranial nerve injury^[13].

Lifestyle changes and prevention

Making certain changes to your diet and exercise habits can help treat carotid artery disease. These healthy changes can also help you maintain a healthy weight and manage high blood pressure and cholesterol^[15].

Lifestyle or medical interventions should address the following risk factors^[11]:

• Hypertension
• High cholesterol
• Smoking

Dietary recommendations

Eat a healthy, low-fat diet^[15]:

• Eat plenty of fruits and vegetables. Fresh or frozen are better choices than canned, which may have added salt or sugar.
• Choose high-fiber foods, such as whole-grain breads, pastas, cereals, and crackers.
• Eat lean meats and skinless chicken and turkey.
• Eat fish twice a week. Fish is good for your arteries.
• Cut back on saturated fat, cholesterol, and added salt and sugar.

Physical activity

Be more active^[15]:

• Talk with your provider first to make sure you are healthy enough to exercise.
• Walking is an easy way to add activity to your day. Start with 10 to 15 minutes a day.
• Start gradually and build up to 150 minutes of exercise a week.

Smoking cessation

Stop smoking if you smoke. Quitting reduces your risk of stroke. Talk with your provider about quit-smoking programs^[15].

Follow-up care

Your provider will want to monitor you and see how well your treatment is working. At these visits, your provider may^[15]:

• Use a stethoscope to listen to the blood flow in your neck
• Check your blood pressure
• Check your cholesterol levels

You may also have imaging tests done to see if the blockages in your carotid arteries are becoming worse^[15].

When to seek emergency care

Having carotid artery disease puts you at risk for stroke. If you think you have symptoms of stroke, go to the emergency room or call 911 or the local emergency number immediately^[15]. Get help as soon as symptoms occur. The sooner you receive treatment, the better your chance for recovery. With a stroke, every second of delay can result in more brain injury^[15].