Carotid Artery Stenosis - Symptoms & Causes

What is carotid artery stenosis?

Carotid artery stenosis, also known as carotid artery disease, is a condition that involves the narrowing of your carotid arteries – the blood vessels located on either side of your neck.

These arteries supply oxygen-rich blood to your head and brain. A narrowing occurs due to the accumulation of plaque, which is composed of fat, cholesterol and other substances found in the blood.

Carotid artery stenosis is a serious condition as too much plaque build-up can prevent the flow of blood to your brain. In other cases, a small piece of plaque may travel to the brain, causing stroke or possibly death.

What are the symptoms of carotid artery stenosis?

Patients with carotid artery stenosis often do not show symptoms until the narrowing reaches the severe stage.

The first sign of carotid artery stenosis may be a stroke or transient ischaemic attack (TIA), which is also known as a “mini-stroke”. A TIA is similar to a stroke, but the symptoms only last a few minutes and usually disappear within an hour.

The symptoms of a stroke or a TIA include:

  • Feeling numb or weak on one side of your face or one side of your body
  • Slurring your speech or having trouble speaking
  • Feeling dizzy, losing your balance, having difficulty walking or lacking coordination
  • Losing your vision or blurring of your vision in one or both eyes
  • Experiencing severe headache with no known cause

What causes carotid artery stenosis?

The main cause of carotid artery stenosis is atherosclerosis. This process is characterised by the formation of plaque along the inner walls of your carotid arteries. Plaques accumulate over time, and the build-up causes your arteries to become stiff and narrow.

When your carotid artery is narrowed, the flow of blood to your brain decreases, consequently reducing the supply of oxygen and other nutrients needed by the brain to function. Sometimes, a small piece of plaque breaks off the artery wall, travels through your bloodstream, and causes a clog in smaller arteries in your brain.

What are the risk factors for carotid artery stenosis?

There are several factors that can raise your risk of developing carotid artery stenosis over time. These include:

  • Hypertension or elevated blood pressure. Extra pressure on artery walls can weaken them and put them at risk of damage.
  • Smoking. Chemicals from tobacco products, including nicotine, can cause damage to the inner lining of your arteries, as well as increase your blood pressure and heart rate.
  • Sedentary lifestyle. Lack of exercise can make you prone to developing conditions that cause damage to your arteries, such as blood pressure, diabetes and obesity.
  • High cholesterol levels. High levels of lipids, including low-density lipoprotein cholesterol and triglycerides, can promote the formation of plaques.
  • Diabetes. This condition impairs your body’s ability to process fats efficiently, thereby increasing your risk of hypertension and atherosclerosis.
  • Obesity. Excess weight raises your odds of having conditions that contribute to carotid artery stenosis, including hypertension, atherosclerosis and diabetes.
  • Age. As you age, your arteries become less flexible and more vulnerable to damage.
  • Family history. Your risk of carotid artery stenosis increases if a family member has atherosclerosis or coronary artery disease.

If you have too much plaque build-up in your carotid arteries, you may develop stroke due to reduced blood flow, plaque rupture and blood clots leading to blockage.

A stroke can lead to serious disability and may even cause death.

How do you prevent carotid artery stenosis?

Preventing or delaying carotid artery stenosis is focused on making lifestyle changes to manage and address modifiable risk factors. These include quitting smoking, exercising regularly, and following a diet that comprises plenty of fruits and limits intake of salt and fatty foods, among others.

This page has been reviewed by our medical content reviewers.

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