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Last full review/revision Jul 2021| Content last modified Jul 2021
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What is atherosclerosis?

Atherosclerosis is known as hardening of the arteries. It's caused by a fat-like buildup (called atheromas or plaques) inside your arteries. Arteries are blood vessels that carry blood to your organs. The buildup slowly blocks the flow of blood through your arteries. Atherosclerosis is the most common cause of heart attacks and strokes.

  • Atherosclerosis is more likely in people with high blood pressure, diabetes, and high cholesterol, and in people who smoke cigarettes

  • Often, the first symptom is pain or cramps in the chest or legs

  • Atherosclerosis is the leading cause of illness and death in the United States

  • To help prevent atherosclerosis, stop smoking, eat a healthy diet, exercise regularly, and treat health problems, such as high blood pressure, diabetes, and high cholesterol

What causes atherosclerosis?

Atherosclerosis starts with repeated, small injuries to the lining of your arteries. The injuries can be caused by:

After your artery's lining is damaged, white blood cells attach to your artery and collect fatty cells and cholesterol. The cells and cholesterol build up to form hard clumps called plaques (atheromas). As the plaques get bigger, they start to block blood flow.

What increases the risk of atherosclerosis?

There are many risk factors for atherosclerosis. You can do things to deal with some risk factors. Other risk factors are out of your control.

Risk factors you can control or avoid include:

These are important risk factors you can't control:

  • Having close relatives with atherosclerosis

  • Being a man

  • Growing older

What are the symptoms of atherosclerosis?

Early atherosclerosis has no symptoms. After many years, symptoms depend on:

  • Where the blocked artery is located

  • Whether it slowly narrows or is suddenly blocked

If arteries slowly narrow, the first symptom is usually pain or cramps, such as chest pain during exercise or leg cramps while walking.

If arteries are suddenly blocked, you may have:

  • A heart attack (blocked artery to the heart)

  • A stroke (blocked artery to the brain)

  • Gangrene of a toe, foot, or leg (blocked artery to the leg)

How can doctors tell if I have atherosclerosis?

If you have symptoms that suggest a blocked artery, doctors will do tests to look for the location and size of the blockage. Doctors do different tests depending on where the artery is. Tests may include:

  • ECG/EKG—a test that measures your heart’s electrical activity

  • Ultrasonography—a test (also called an ultrasound) that uses sound waves to create a moving picture of the insides of your body and your blood vessels

  • Stress test—doctors see how your heart works when it’s under stress, such as when you exercise

  • Cardiac catheterization—doctors thread a catheter (small flexible tube) into your body and up to your heart

If you have atherosclerosis, doctors will do blood tests to look for what caused it.

How do doctors treat and prevent atherosclerosis?

Changes to your lifestyle and taking medicines may stop the fatty build-up from growing or from having new blockages form.

You can lower your risk factors:

  • Stop smoking

  • Eat a healthy diet

  • Exercise

  • Take your medicines to lower cholesterol and blood pressure and control diabetes, as directed by your doctors

If you're likely to get atherosclerosis, your doctor may have you take aspirin and a medicine called a statin.

If changes to your lifestyle and taking medicines don't help, doctors may have to do surgery. The surgery is done to remove the blockage or redirect blood flow around the blockage.

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