What is atherosclerosis?

In people with atherosclerosis, patchy deposits of fatty material (atheromas or atherosclerotic plaques) develop in the walls of medium-sized and large arteries, leading to reduced or blocked blood flow.

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Atherosclerosis

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Last full review/revision Jul 2021| Content last modified Jul 2021

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Topic Resources

Normal Blood Vessel and Partially Blocked Blood Vessel

Blood Vessels

Fatty Deposits in a Coronary Artery

Exercise Tolerance (Stress) Testing

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 Heart Attack A heart attack is when blood flow to part of your heart is suddenly blocked and some of your heart muscle dies. Doctors use the term myocardial infarction to refer to a heart attack. Myocardium... read more and strokes Stroke A stroke is a sudden brain problem that happens when a blood vessel in your brain either gets blocked or breaks open and bleeds. Part of your brain stops getting blood. Brain tissue that doesn't... read more .

Atherosclerosis is more likely in people with high blood pressure High Blood Pressure Each heart beat pushes blood through your arteries. Arteries are the blood vessels that carry blood from your heart to your body. Blood pressure is the pressure of blood in your arteries. Without... read more , diabetes Diabetes Diabetes is a disease in which your blood sugar (glucose) levels are too high. You get diabetes if your body's normal way of controlling blood sugar isn't working right. There are 2 types of... read more , and high cholesterol High Cholesterol Cholesterol is a type of fat. Fats are also called lipids. Your body uses cholesterol to build important parts of cells and to make certain digestive juices. Your body needs cholesterol. But... read more , 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 High Blood Pressure Each heart beat pushes blood through your arteries. Arteries are the blood vessels that carry blood from your heart to your body. Blood pressure is the pressure of blood in your arteries. Without... read more , diabetes Diabetes Diabetes is a disease in which your blood sugar (glucose) levels are too high. You get diabetes if your body's normal way of controlling blood sugar isn't working right. There are 2 types of... read more , and high cholesterol High Cholesterol Cholesterol is a type of fat. Fats are also called lipids. Your body uses cholesterol to build important parts of cells and to make certain digestive juices. Your body needs cholesterol. But... read more

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.

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:

Smoking cigarettes
High cholesterol High Cholesterol Cholesterol is a type of fat. Fats are also called lipids. Your body uses cholesterol to build important parts of cells and to make certain digestive juices. Your body needs cholesterol. But... read more
High blood pressure High Blood Pressure Each heart beat pushes blood through your arteries. Arteries are the blood vessels that carry blood from your heart to your body. Blood pressure is the pressure of blood in your arteries. Without... read more
Diabetes Diabetes Diabetes is a disease in which your blood sugar (glucose) levels are too high. You get diabetes if your body's normal way of controlling blood sugar isn't working right. There are 2 types of... read more
Being overweight, especially in your belly
Not exercising
Eating too much saturated fat, such as butter, and not enough fruits and vegetables

These are important risk factors you can't control:

Having close relatives with atherosclerosis
Being a man
Growing older

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 Heart Attack A heart attack is when blood flow to part of your heart is suddenly blocked and some of your heart muscle dies. Doctors use the term myocardial infarction to refer to a heart attack. Myocardium... read more (blocked artery to the heart)
A stroke Stroke A stroke is a sudden brain problem that happens when a blood vessel in your brain either gets blocked or breaks open and bleeds. Part of your brain stops getting blood. Brain tissue that doesn't... read more (blocked artery to the brain)
Gangrene of a toe, foot, or leg (blocked artery to the leg)

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 Electrocardiography Electrocardiography is a test that measures your heart’s electrical activity. It's quick, painless, and harmless. The results of that test are shown in an electrocardiogram. It looks like a... read more —a test that measures your heart’s electrical activity
Ultrasonography Ultrasonography Ultrasonography is a safe imaging test that uses sound waves to create a moving picture of the insides of your body. Ultrasonography doesn't use radiation (x-rays). Ultrasonography is also called... read more —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 Stress Testing A stress test lets doctors see how your heart works when it’s under stress, such as when you exercise. Many heart problems are easier for your doctor to find when your heart is working hard... read more —doctors see how your heart works when it’s under stress, such as when you exercise
Cardiac catheterization Cardiac Catheterization Cardiac is a medical term for the heart. Catheterization means to put a thin, hollow tube (catheter) into some part of your body. So in cardiac catheterization (cardiac cath): Your doctor puts... read more —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.

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.