What is carotid artery disease?

The carotid arteries are the main blood vessels that send blood and oxygen to the brain. When these vessels become narrowed, it’s called carotid artery disease. It may also be called carotid artery stenosis. The narrowing is caused by atherosclerosis. This is the buildup of fatty deposits, calcium and other things inside the artery. Carotid artery disease is like coronary artery disease. In that disease, buildup occurs in the arteries of the heart, which can cause a heart attack.

Carotid artery disease reduces the flow of oxygen to the brain. The brain needs a constant supply of oxygen to work. Even a brief pause in blood supply can cause problems. Brain cells start to die after just a few minutes without blood or oxygen. If the narrowing of the carotid arteries is severe enough that blood flow is blocked, it can cause a stroke. If a piece of plaque breaks off it can block blood flow to the brain. This too can cause a stroke.

Who is at risk for carotid artery disease?

Risk factors linked with atherosclerosis include:

  • Older age

  • Male

  • Family history

  • Race

  • Genetic factors

  • High cholesterol

  • High blood pressure

  • Smoking

  • Diabetes

  • Overweight

  • Diet high in saturated fat

  • Lack of exercise

These factors increase a person's risk. But they don't always cause the disease. Knowing your risk factors can help you make lifestyle changes.You can work with your healthcare provider to reduce the chance you will get the disease.

What are the symptoms of carotid artery disease?

The disease may have no symptoms. In some cases, the first sign of the disease is a transient ischemic attack (TIA) or stroke.

A TIA is a sudden, short-term loss of blood flow to a part of the brain. It usually lasts a few minutes to an hour. Symptoms go away fully within 24 hours. There are no lasting effects. When symptoms continue, it is a stroke. Symptoms of a TIA or stroke may include:

  • Sudden weakness or clumsiness of an arm or leg on one side of the body

  • Sudden paralysis of an arm or leg on one side of the body

  • Loss of coordination or movement

  • Confusion, loss of ability to concentrate 

  • Dizziness, fainting or headache

  • Numbness or loss of feeling in the face or in an arm or leg

  • Temporary loss of vision or blurred vision

  • Inability to speak clearly or slurred speech

If you or a loved one has any of these symptoms, call for medical help right away. A TIA may be a warning sign that a stroke is about to occur, but TIAs don't precede all strokes. The symptoms of a TIA and stroke are the same. A stroke is loss of blood flow (ischemia) to the brain that lasts long enough to cause brain damage. Brain cells start to die after just a few minutes without oxygen.

The effects after a stroke depend on the size and place in the brain that had loss of blood flow. This may include problems with:

  • Moving

  • Speaking

  • Thinking

  • Remembering

  • Bowel and bladder function

  • Eating

  • Emotional control

  • Other vital body functions

Recovery also depends on the size and place of the stroke. A stroke may result in long-term problems, such as weakness in an arm or leg. It may cause paralysis, loss of speech or even death.

The symptoms of carotid artery disease may look like other health problems. See your healthcare provider for a diagnosis.

How is carotid artery disease diagnosed?

Your healthcare provider will ask about your health history. He or she will give you a physical exam. You will need tests. These may include:

  • Listening to the carotid arteries. For this test, your healthcare provider places a stethoscope over the carotid artery. This is done to listen for a sound called a bruit (BREW-ee). This sound is made when blood passes through a narrowed artery. A bruit can be a sign of atherosclerosis. But, an artery may be diseased and not make this sound.

  • Carotid artery duplex scan. This test is done to assess the blood flow of the carotid arteries. A probe called a transducer sends out ultrasonic sound waves. The transducer is also like a microphone. It is placed on the carotid arteries at certain locations and angles. The sound waves move through the skin and other body tissues to the blood vessels. The sound waves echo off the blood cells. The transducer sends the waves to an amplifier. Your healthcare provider can hear the sound waves. Not enough or no sounds may mean blood flow is blocked.

  • MRI. This test uses large magnets, radio waves and a computer to make detailed images of tissues in the body. For this test, you lie inside a big tube while magnets pass around your body. It’s very loud. 

  • MR angiography (MRA). This test uses MRI technology and IV contrast dye to make the blood vessels visible. Contrast dye causes blood vessels to show up well on the MRI image so the doctor can see them.

  • CT angiography (CTA). This test uses X-rays and a computer along with contrast dye to make detailed images of the body. A CTA shows pictures of blood vessels and tissues. It helps find narrowed blood vessels.  

  • Angiography. This test is used to see how blocked the carotid arteries are. It is done by taking X-ray images while a contrast dye is injected. The contrast dye shows the shape and flow of blood through the arteries as X-ray images are made.

How is carotid artery disease treated?

Treatment will depend on your symptoms, age and general health. It will also depend on how severe the condition is.

If a carotid artery is less than half narrowed, it is often treated with medicine and lifestyle changes. If the artery is between 50% and 70% narrowed, medicine or surgery may be done. 

Lifestyle changes

  • Quitting smoking. This can reduce the risk for carotid artery disease and cardiovascular disease. All nicotine products, including electronic cigarettes, constrict blood vessels causing blood flow through the arteries to be decreased.

  • Lowering cholesterol. Eat a low-fat, low-cholesterol diet. Eat plenty of vegetables, lean meats (no red meats), fruits and high-fiber grains. Don't eat processed foods, or foods high in saturated and trans-fats. When diet and exercise are not enough to control cholesterol, you may need medicine.

  • Lowering blood sugar. High blood sugar (glucose) can cause damage to the lining of the carotid arteries. Control glucose levels through a low-sugar diet and regular exercise. If you have diabetes, you may need medicine or other treatment.

  • Exercising. Lack of exercise can cause weight gain. It can raise blood pressure and cholesterol. Exercise can help you keep a healthy weight and reduce risks for carotid artery disease.

  • Lowering blood pressure. High blood pressure causes wear and tear and inflammation in blood vessels. This raises the risk for artery narrowing. Blood pressure should be below 140/90 mm/Hg for most people. People with diabetes may need even lower blood pressure.


Medicines that may be used include:

  • Antiplatelets. These medicines make platelets in the blood less able to stick together and cause clots. These medicines include aspirin, clopidogrel, and dipyridamole.

  • Cholesterol medicines. Statins are a type of medicine that lower cholesterol. They include simvastatin and atorvastatin. Studies have shown that some statins can decrease the thickness of the carotid artery wall. This can increase the size of the opening of the artery.

  • Blood pressure medicines. Several types of medicine work to lower blood pressure.

If a carotid artery is narrowed from 50% to 70%, you may need stronger treatment, especially if you have symptoms.


Surgery is usually advised for carotid narrowing of more than 70%. Surgery lowers the risk for stroke after symptoms such as TIA or minor stroke.

Types of surgery include:

  • TransCarotid Artery Revascularization (TCAR). This new procedure involves direct access to the carotid artery, but through a much smaller incision at the neckline just above the clavicle compared to a longer incision on the neck with CEA.
  • Carotid endarterectomy (CEA). This is surgery to remove plaque and blood clots from the carotid arteries. CEA may help prevent a stroke in people who have symptoms and a narrowing of 70% or more.

  • Carotid artery angioplasty with stenting (CAS). This is an option for people who are unable to have CEA. It uses a very small tube (catheter). This tube is put into a blood vessel in the groin. It is pushed up to the carotid arteries. Once the tube is in place, a small balloon is inflated at the tip of it. This opens the artery. Then a stent is put in place. A stent is a thin, metal-mesh tube. It is used to hold the artery open.

What are possible complications of carotid artery disease?

The main complication is a stroke. A stroke can cause serious disability and may cause death.

Can carotid artery disease be prevented?

You can prevent or delay the disease like you would prevent heart disease. This includes:

  • Diet changes. Eat a healthy diet. It should include plenty of fresh fruits and vegetables. Eat lean meats such as poultry and fish, and eat low-fat or non-fat dairy foods. Limit your intake of salt, sugar, processed foods, saturated fats and alcohol. 

  • Exercise. Aim for 40 minutes of moderate to vigorous physical activity at least 3 to 4 days per week.

  • Manage your weight. If you are overweight, take steps to lose weight. 

  • Quit smoking. If you smoke, break the habit. Enroll in a stop-smoking program. This can improve your chances of success. Ask your doctor about prescription medicine.

  • Control stress. Learn ways to manage stress in your home and work life.