Atherosclerosis (ath-er-o-skler-O-sis) is a disease in which plaque (plak) builds up inside your arteries. Arteries are blood vessels that carry oxygen-rich blood to your heart and other parts of your body.
Plaque is made up of fat, cholesterol, calcium, and other substances found in the blood. Over time, plaque hardens and narrows your arteries. This limits the flow of oxygen-rich blood to your organs and other parts of your body.
Atherosclerosis can affect any artery in the body, including arteries in the heart, brain, arms, legs, pelvis, and kidneys. As a result, different diseases may develop based on which arteries are affected.
Coronary heart disease (CHD), also called coronary artery disease, is the #1 killer of both men and women in the United States. CHD occurs if plaque builds up in the coronary arteries. These arteries supply oxygen-rich blood to your heart.
Plaque narrows the coronary arteries and reduces blood flow to your heart muscle. Plaque buildup also makes it more likely that blood clots will form in your arteries. Blood clots can partially or completely block blood flow.
If blood flow to your heart muscle is reduced or blocked, you may have angina (chest pain or discomfort) or a heart attack.
Plaque also can form in the heart's smallest arteries. This disease is called coronary microvascular disease (MVD). In coronary MVD, plaque doesn't cause blockages in the arteries as it does in CHD.
Carotid (ka-ROT-id) artery disease occurs if plaque builds up in the arteries on each side of your neck (the carotid arteries). These arteries supply oxygen-rich blood to your brain. If blood flow to your brain is reduced or blocked, you may have a stroke.
Peripheral arterial disease (P.A.D.) occurs if plaque builds up in the major arteries that supply oxygen-rich blood to your legs, arms, and pelvis.
If blood flow to these parts of your body is reduced or blocked, you may have numbness, pain, and, sometimes, dangerous infections.
Chronic kidney disease can occur if plaque builds up in the renal arteries. These arteries supply oxygen-rich blood to your kidneys.
Over time, chronic kidney disease causes a slow loss of kidney function. The main function of the kidneys is to remove waste and extra water from the body.
The cause of atherosclerosis isn't known. However, certain traits, conditions, or habits may raise your risk for the disease. These conditions are known as risk factors.
Some people who have atherosclerosis have no signs or symptoms. They may not be diagnosed until after a heart attack or stroke.
The main treatment for atherosclerosis is lifestyle changes. You also may need medicines and medical procedures. These treatments, along with ongoing medical care, can help you live a healthier life.
Improved treatments have reduced the number of deaths from atherosclerosis-related diseases. These treatments also have improved the quality of life for people who have these diseases. However, atherosclerosis remains a common health problem.
You may be able to prevent or delay atherosclerosis and the diseases it can cause. Making lifestyle changes and getting ongoing care can help you avoid the problems of atherosclerosis and live a long, healthy life.
The exact cause of atherosclerosis isn't known. However, studies show that atherosclerosis is a slow, complex disease that may start in childhood. It develops faster as you age.
Atherosclerosis may start when certain factors damage the inner layers of the arteries. These factors include:
Plaque may begin to build up where the arteries are damaged. Over time, plaque hardens and narrows the arteries. Eventually, an area of plaque can rupture (break open).
When this happens, blood cell fragments called platelets (PLATE-lets) stick to the site of the injury. They may clump together to form blood clots. Clots narrow the arteries even more, limiting the flow of oxygen-rich blood to your body.
Researchers continue to look for the causes of atherosclerosis. They hope to find answers to questions such as:
Coronary heart disease (atherosclerosis of the coronary arteries) is the #1 killer of both men and women in the United States.
The exact cause of atherosclerosis isn't known. However, certain traits, conditions, or habits may raise your risk for the disease. These conditions are known as risk factors. The more risk factors you have, the more likely it is that you'll develop atherosclerosis.
You can control most risk factors and help prevent or delay atherosclerosis. Other risk factors can't be controlled.
Although age and a family history of early heart disease are risk factors, it doesn't mean that you'll develop atherosclerosis if you have one or both. Controlling other risk factors often can lessen genetic influences and prevent atherosclerosis, even in older adults.
Studies show that an increasing number of children and youth are at risk for atherosclerosis. This is due to a number of causes, including rising childhood obesity rates.
Scientists continue to study other possible risk factors for atherosclerosis.
High levels of a protein called C-reactive protein (CRP) in the blood may raise the risk for atherosclerosis and heart attack. High levels of CRP are a sign of inflammation in the body.
Inflammation is the body's response to injury or infection. Damage to the arteries' inner walls seems to trigger inflammation and help plaque grow.
People who have low CRP levels may develop atherosclerosis at a slower rate than people who have high CRP levels. Research is under way to find out whether reducing inflammation and lowering CRP levels also can reduce the risk for atherosclerosis.
High levels of triglycerides (tri-GLIH-seh-rides) in the blood also may raise the risk for atherosclerosis, especially in women. Triglycerides are a type of fat.
Studies are under way to find out whether genetics may play a role in atherosclerosis risk.
Other factors also may raise your risk for atherosclerosis, such as:
Atherosclerosis usually doesn't cause signs and symptoms until it severely narrows or totally blocks an artery. Many people don't know they have the disease until they have a medical emergency, such as a heart attack or stroke.
Some people may have signs and symptoms of the disease. Signs and symptoms will depend on which arteries are affected.
The coronary arteries supply oxygen-rich blood to your heart. If plaque narrows or blocks these arteries (a disease called coronary heart disease, or CHD), a common symptom is angina. Angina is chest pain or discomfort that occurs when your heart muscle doesn't get enough oxygen-rich blood.
Angina may feel like pressure or squeezing in your chest. You also may feel it in your shoulders, arms, neck, jaw, or back. Angina pain may even feel like indigestion. The pain tends to get worse with activity and go away with rest. Emotional stress also can trigger the pain.
Other symptoms of CHD are shortness of breath and arrhythmias (ah-RITH-me-ahs). Arrhythmias are problems with the rate or rhythm of the heartbeat.
Plaque also can form in the heart's smallest arteries. This disease is called coronary microvascular disease (MVD). Symptoms of coronary MVD include angina, shortness of breath, sleep problems, fatigue (tiredness), and lack of energy.
The carotid arteries supply oxygen-rich blood to your brain. If plaque narrows or blocks these arteries (a disease called carotid artery disease), you may have symptoms of a stroke. These symptoms may include:
Plaque also can build up in the major arteries that supply oxygen-rich blood to the legs, arms, and pelvis (a disease called peripheral arterial disease).
If these major arteries are narrowed or blocked, you may have numbness, pain, and, sometimes, dangerous infections.
The renal arteries supply oxygen-rich blood to your kidneys. If plaque builds up in these arteries, you may develop chronic kidney disease. Over time, chronic kidney disease causes a slow loss of kidney function.
Early kidney disease often has no signs or symptoms. As the disease gets worse it can cause tiredness, changes in how you urinate (more often or less often), loss of appetite, nausea (feeling sick to the stomach), swelling in the hands or feet, itchiness or numbness, and trouble concentrating.
Your doctor will diagnose atherosclerosis based on your medical and family histories, a physical exam, and test results.
If you have atherosclerosis, a primary care doctor, such as an internist or family practitioner, may handle your care. Your doctor may recommend other health care specialists if you need expert care, such as:
During the physical exam, your doctor may listen to your arteries for an abnormal whooshing sound called a bruit (broo-E). Your doctor can hear a bruit when placing a stethoscope over an affected artery. A bruit may indicate poor blood flow due to plaque buildup.
Your doctor also may check to see whether any of your pulses (for example, in the leg or foot) are weak or absent. A weak or absent pulse can be a sign of a blocked artery.
Your doctor may recommend one or more tests to diagnose atherosclerosis. These tests also can help your doctor learn the extent of your disease and plan the best treatment.
Blood tests check the levels of certain fats, cholesterol, sugar, and proteins in your blood. Abnormal levels may be a sign that you're at risk for atherosclerosis.
An EKG is a simple, painless test that detects and records the heart's electrical activity. The test shows how fast the heart is beating and its rhythm (steady or irregular). An EKG also records the strength and timing of electrical signals as they pass through the heart.
An EKG can show signs of heart damage caused by CHD. The test also can show signs of a previous or current heart attack.
This test compares the blood pressure in your ankle with the blood pressure in your arm to see how well your blood is flowing. This test can help diagnose P.A.D.
Echocardiography (echo) uses sound waves to create a moving picture of your heart. The test provides information about the size and shape of your heart and how well your heart chambers and valves are working.
Echo also can identify areas of poor blood flow to the heart, areas of heart muscle that aren't contracting normally, and previous injury to the heart muscle caused by poor blood flow.
A computed tomography (CT) scan creates computer-generated pictures of the heart, brain, or other areas of the body. The test can show hardening and narrowing of large arteries.
A cardiac CT scan also can show whether calcium has built up in the walls of the coronary (heart) arteries. This may be an early sign of CHD.
During stress testing, you exercise to make your heart work hard and beat fast while heart tests are done. If you can't exercise, you may be given medicine to make your heart work hard and beat fast.
When your heart is working hard, it needs more blood and oxygen. Plaque-narrowed arteries can't supply enough oxygen-rich blood to meet your heart's needs.
A stress test can show possible signs and symptoms of CHD, such as:
As part of some stress tests, pictures are taken of your heart while you exercise and while you rest. These imaging stress tests can show how well blood is flowing in various parts of your heart. They also can show how well your heart pumps blood when it beats.
Angiography (an-jee-OG-ra-fee) is a test that uses dye and special x rays to show the inside of your arteries. This test can show whether plaque is blocking your arteries and how severe the blockage is.
A thin, flexible tube called a catheter is put into a blood vessel in your arm, groin (upper thigh), or neck. Dye that can be seen on an x-ray picture is injected through the catheter into the arteries. By looking at the x-ray picture, your doctor can see the flow of blood through your arteries.
Other tests are being studied to see whether they can give a better view of plaque buildup in the arteries. Examples of these tests include magnetic resonance imaging (MRI) and positron emission tomography (PET).
Treatments for atherosclerosis may include lifestyle changes, medicines, and medical procedures or surgery.
The goals of treatment include:
Making lifestyle changes often can help prevent or treat atherosclerosis. For some people, these changes may be the only treatment needed.
For information about healthy eating, go to the National Heart, Lung, and Blood Institute's (NHLBI's) Aim for a Healthy Weight Web site. This site provides practical tips on healthy eating, physical activity, and weight control.
Therapeutic Lifestyle Changes (TLC). Your doctor may recommend TLC if you have high blood cholesterol. TLC is a three-part program that includes a healthy diet, physical activity, and weight management.
With the TLC diet, less than 7 percent of your daily calories should come from saturated fat. This kind of fat is found in some meats, dairy products, chocolate, baked goods, and deep-fried and processed foods.
No more than 25 to 35 percent of your daily calories should come from all fats, including saturated, trans, monounsaturated, and polyunsaturated fats.
You also should have less than 200 mg a day of cholesterol. The amounts of cholesterol and the types of fat in prepared foods can be found on the foods' Nutrition Facts labels.
Foods high in soluble fiber also are part of a healthy diet. They help prevent the digestive tract from absorbing cholesterol. These foods include:
A diet rich in fruits and vegetables can increase important cholesterol-lowering compounds in your diet. These compounds, called plant stanols or sterols, work like soluble fiber.
A healthy diet also includes some types of fish, such as salmon, tuna (canned or fresh), and mackerel. These fish are a good source of omega-3 fatty acids. These acids may help protect the heart from blood clots and inflammation and reduce the risk for heart attack. Try to have about two fish meals every week.
You should try to limit the amount of sodium (salt) that you eat. This means choosing low-salt and "no added salt" foods and seasonings at the table or while cooking. The Nutrition Facts label on food packaging shows the amount of sodium in the item.
Try to limit drinks with alcohol. Too much alcohol will raise your blood pressure and triglyceride level. (Triglycerides are a type of fat found in the blood.) Alcohol also adds extra calories, which will cause weight gain.
Men should have no more than two drinks containing alcohol a day. Women should have no more than one drink containing alcohol a day. One drink is a glass of wine, beer, or a small amount of hard liquor.
For more information about TLC, go to the NHLBI's "Your Guide to Lowering Your Cholesterol With TLC."
Dietary Approaches to Stop Hypertension (DASH). Your doctor may recommend the DASH eating plan if you have high blood pressure. The DASH eating plan focuses on fruits, vegetables, whole grains, and other foods that are heart healthy and low in fat, cholesterol, and salt.
DASH also focuses on fat-free or low-fat milk and dairy products, fish, poultry, and nuts. The DASH eating plan is reduced in red meats (including lean red meats), sweets, added sugars, and sugar-containing beverages. The plan is rich in nutrients, protein, and fiber.
The DASH eating plan is a good heart healthy eating plan, even for those who don't have high blood pressure. For more information, go to the NHLBI's "Your Guide to Lowering Your Blood Pressure With DASH."
Regular physical activity can lower many atherosclerosis risk factors, including LDL ("bad") cholesterol, high blood pressure, and excess weight.
Physical activity also can lower your risk for diabetes and raise your HDL cholesterol level. HDL is the "good" cholesterol that helps prevent atherosclerosis.
Talk with your doctor before you start a new exercise plan. Ask him or her how much and what kinds of physical activity are safe for you.
People gain health benefits from as little as 60 minutes of moderate-intensity aerobic activity per week. For major health benefits, do at least 150 minutes
For more information about physical activity, go to the U.S. Department of Health and Human Services' "2008 Physical Activity Guidelines for Americans," the Health Topics Physical Activity and Your Heart article, and the NHLBI's "Your Guide to Physical Activity and Your Heart."
Maintaining a healthy weight can lower your risk for atherosclerosis. A general goal to aim for is a body mass index (BMI) of less than 25.
BMI measures your weight in relation to your height and gives an estimate of your total body fat. You can use the NHLBI's online BMI calculator to figure out your BMI, or your doctor can help you.
A BMI between 25 and 29.9 is considered overweight. A BMI of 30 or more is considered obese. A BMI of less than 25 is the goal for preventing and treating atherosclerosis. Your doctor or health care provider can help you set an appropriate BMI goal.
For more information about losing weight or maintaining your weight, go to the Health Topics Overweight and Obesity article.
If you smoke or use tobacco, quit. Smoking can damage and tighten blood vessels and raise your risk for atherosclerosis. Talk with your doctor about programs and products that can help you quit. Also, try to avoid secondhand smoke.
If you have trouble quitting smoking on your own, consider joining a support group. Many hospitals, workplaces, and community groups offer classes to help people quit smoking.
Research shows that the most commonly reported "trigger" for a heart attack is an emotionally upsetting event—particularly one involving anger. Also, some of the ways people cope with stress—such as drinking, smoking, or overeating—aren't healthy.
Learning how to manage stress, relax, and cope with problems can improve your emotional and physical health. Having supportive people in your life with whom you can share your feelings or concerns can help relieve stress.
Physical activity, medicine, and relaxation therapy also can help relieve stress. You may want to consider taking part in a stress management program.
To slow the progress of plaque buildup, your doctor may prescribe medicines to help lower your cholesterol level or blood pressure. He or she also may prescribe medicines to prevent blood clots from forming.
For successful treatment, take all medicines as your doctor prescribes.
If you have severe atherosclerosis, your doctor may recommend a medical procedure or surgery.
Angioplasty (AN-jee-oh-plas-tee) is a procedure that's used to open blocked or narrowed coronary (heart) arteries. Angioplasty can improve blood flow to the heart and relieve chest pain. Sometimes a small mesh tube called a stent is placed in the artery to keep it open after the procedure.
Coronary artery bypass grafting (CABG) is a type of surgery. In CABG, arteries or veins from other areas in your body are used to bypass (that is, go around) your narrowed coronary arteries. CABG can improve blood flow to your heart, relieve chest pain, and possibly prevent a heart attack.
Bypass grafting also can be used for leg arteries. For this surgery, a healthy blood vessel is used to bypass a narrowed or blocked artery in one of the legs. The healthy blood vessel redirects blood around the blocked artery, improving blood flow to the leg.
Carotid endarterectomy (END-ar-ter-EK-to-me) is surgery to remove plaque buildup from the carotid arteries in the neck. This procedure restores blood flow to the brain, which can help prevent a stroke.
Taking action to control your risk factors can help prevent or delay atherosclerosis and its related diseases. Your risk for atherosclerosis increases with the number of risk factors you have.
One step you can take is to adopt a healthy lifestyle. Following a healthy diet is an important part of a healthy lifestyle.
A healthy diet includes a variety of fruits and vegetables (including beans and peas). It also includes whole grains, lean meats, poultry without skin, seafood, and fat-free or low-fat milk and dairy products. A healthy diet is low in sodium (salt), added sugar, solid fats, and refined grains.
If you're overweight or obese, work with your doctor to create a reasonable weight-loss plan. Controlling your weight helps you control atherosclerosis risk factors.
Be as physically active as you can. Physical activity can improve your fitness level and your health. Ask your doctor what types and amounts of activity are safe for you.
If you smoke, quit. Smoking can damage and tighten blood vessels and raise your risk for atherosclerosis. Talk with your doctor about programs and products that can help you quit. Also, try to avoid secondhand smoke.
Know your family history of atherosclerosis. If you or someone in your family has an atherosclerosis-related disease, be sure to tell your doctor.
If lifestyle changes aren't enough, your doctor may prescribe medicines to control your atherosclerosis risk factors. Take all of your medicines as your doctor advises.
For more information about lifestyle changes and medicines, go to "How Is Atherosclerosis Treated?"
Improved treatments have reduced the number of deaths from atherosclerosis-related diseases. These treatments also have improved the quality of life for people who have these diseases.
Adopting a healthy lifestyle may help you prevent or delay atherosclerosis and the problems it can cause. This, along with ongoing medical care, can help you avoid the problems of atherosclerosis and live a long, healthy life.
Researchers continue to look for ways to improve the health of people who have atherosclerosis or may develop it.
Follow your treatment plan and take all of your medicines as your doctor prescribes. Your doctor will let you know how often you should schedule office visits or blood tests. Be sure to let your doctor know if you have new or worsening symptoms.
Having an atherosclerosis-related disease may cause fear, anxiety, depression, and stress. Talk about how you feel with your doctor. Talking to a professional counselor also can help. If you're very depressed, your doctor may recommend medicines or other treatments that can improve your quality of life.
Community resources are available to help you learn more about atherosclerosis. Contact your local public health departments, hospitals, and local chapters of national health organizations to learn more about available resources in your area.
Talk about your lifestyle changes with your family and friends—whoever can provide support or needs to understand why you're changing your habits.
Family and friends may be able to help you make lifestyle changes. For example, they can help you plan healthier meals. Because atherosclerosis tends to run in families, your lifestyle changes may help many of your family members too.
The National Heart, Lung, and Blood Institute (NHLBI) is strongly committed to supporting research aimed at preventing and treating heart, lung, and blood diseases and conditions and sleep disorders.
NHLBI-supported research has led to many advances in medical knowledge and care. However, many questions remain about various diseases and conditions, including atherosclerosis.
The NHLBI continues to support research aimed at learning more about atherosclerosis and its related diseases. For example, NHLBI-supported research includes studies that:
Much of this research depends on the willingness of volunteers to take part in clinical trials. Clinical trials test new ways to prevent, diagnose, or treat various diseases and conditions.
For example, new treatments for a disease or condition (such as medicines, medical devices, surgeries, or procedures) are tested in volunteers who have the illness. Testing shows whether a treatment is safe and effective in humans before it is made available for widespread use.
By taking part in a clinical trial, you can gain access to new treatments before they're widely available. You also will have the support of a team of health care providers, who will likely monitor your health closely. Even if you don't directly benefit from the results of a clinical trial, the information gathered can help others and add to scientific knowledge.
If you volunteer for a clinical trial, the research will be explained to you in detail. You'll learn about treatments and tests you may receive, and the benefits and risks they may pose. You'll also be given a chance to ask questions about the research. This process is called informed consent.
If you agree to take part in the trial, you'll be asked to sign an informed consent form. This form is not a contract. You have the right to withdraw from a study at any time, for any reason. Also, you have the right to learn about new risks or findings that emerge during the trial.
For more information about clinical trials related to atherosclerosis and its related diseases, talk with your doctor. You also can visit the following Web sites to learn more about clinical research and to search for clinical trials:
For more information about clinical trials for children, visit the NHLBI's Children and Clinical Studies Web page.
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