Carotid Artery Disease

What is carotid artery disease?

Carotid artery disease is a condition that causes the carotid arteries to become narrow or blocked. The carotid arteries are 2 large blood vessels on each side of the neck. These blood vessels bring blood to the brain and eyes. A narrowing or blockage of the arteries slows or stops blood flow to the head and can cause temporary symptoms such as dizziness, feeling faint, partial blindness, or numb feelings. A blocked carotid artery can also cause stroke or death.

How does it occur?

The usual cause of a partial or complete blockage is a condition called atherosclerosis. Commonly known as hardening of the arteries, atherosclerosis is caused by a buildup of plaque on the inside walls of the arteries. Plaque is made up of scar tissue, blood cells that have moved from the bloodstream into the artery wall, cholesterol, and other fatty substances.

The buildup of plaque narrows the arteries and slows the flow of blood. Plaque may break off. A blood clot may form at the site of the break. The blood clot can block blood flow to the brain even more. Pieces of the clot may break away and float to the brain's smaller arteries, causing a stroke when they block these arteries.

What are the symptoms?

Most people with carotid artery disease have no symptoms. When the disease causes symptoms, the risk of a major stroke increases.

The most common symptoms are transient ischemic attacks (TIAs), which are sometimes called mini-strokes. TIAs can cause temporary decreases in blood flow to part of the brain, causing temporary symptoms such as:

• partial blindness
• numbness and tingling of the skin
• weakness of an arm or a leg.

TIAs usually last less than 30 minutes, but they can last up to 24 hours. People who have had a TIA are more likely to have a stroke.

A stroke happens when part of the brain is damaged by a lack of blood and there is a loss of brain function. A stroke causes symptoms such as paralysis of an arm or leg, vision and speech problems, and personality changes. Strokes are the third leading cause of death in the US.

How is it diagnosed?

It is important to tell your healthcare provider if you have had temporary problems with vision or minor paralysis. A routine physical exam usually detects carotid artery disease, even if you have no symptoms. Your provider may hear a murmur by listening to the carotid artery in your neck with a stethoscope. The murmur is caused by blood moving through a narrowed part of the artery.

Tests you may have are:

• ultrasound test, which can show a blockage, its size, and the amount of blood flowing through the artery.
• cerebral arteriogram, which is an X-ray dye procedure that shows how narrow the inside of the artery is and the exact location of the blockage.
• CT scan (computerized X-rays) of the head, which uses X-rays to outline the brain structures to rule out a recent stroke.
• MRI (magnetic resonance imaging), which uses magnetism, radio waves, and a computer to make pictures that can show blocked blood vessels.

How is it treated?

If you have some blockage of a carotid artery but have no symptoms, the usual treatment is medicine. Your healthcare provider may prescribe medicine that thins the blood or prevents blood clots. Aspirin and warfarin are 2 common examples of these types of medicines. An aspirin a day is the treatment most healthcare providers now recommend. Aspirin reduces the tendency of blood to form a clot. This decreases the chance of stroke. You may also benefit from surgery.

If you have symptoms but less than a 70% blockage of a carotid artery, you will probably need a cerebral arteriogram. If this test shows no other problems, you will start aspirin treatment. If the plaque looks rough and irregular on the X-ray, your healthcare provider might recommend surgery because the irregular plaque might form clots, possibly causing a stroke.

If you have symptoms and more than a 70% blockage of a carotid artery, you will likely need surgery. The surgery, called carotid endarterectomy, involves making cuts in your neck and the artery and then removing the blockage.

Carotid angioplasty and stenting, used in some hospitals, involves passing a balloon-tipped tube (catheter) into the carotid artery blockage. Once the catheter is in the proper place, the balloon is inflated. The balloon stretches keep it open and allow blood to flow through the blood vessel. More experience with this procedure is needed before it becomes common.

How long will the effects last?

Carotid artery disease cannot be completely eliminated, but you can control it. The goal of treatment is to prevent more blockage and stroke. Both aspirin and surgery reduce but do not entirely eliminate the risk of stroke.

How can I take care of myself?

Follow the treatment plan prescribed by your healthcare provider.

Call your provider right away if:

• You have temporary blindness or vision problems.
• You notice weakness of an arm or a leg.
• You start having trouble speaking.
• You become aware of a swishing noise in either ear that is related to your heartbeat. The noise may indicate blood flowing past a blockage in a carotid artery.

What can I do to help prevent carotid artery disease?

In almost all cases, atherosclerosis is the cause of carotid artery disease. You can help prevent atherosclerosis by following these guidelines:

• Eat foods low in fat and cholesterol.
• Lose weight if you are overweight.
• Exercise regularly according to your healthcare provider's recommendations.
• Lower your blood pressure if it is high.
• Don't smoke.
• Try to reduce stress in your life.
• Lower your blood sugar if it is high.
• If you have diabetes, see your healthcare provider regularly and follow all diet and medication instructions.