Coronary artery disease develops when the major blood vessels that supply your heart with blood, oxygen and nutrients (coronary arteries) become damaged or diseased. Cholesterol-containing deposits (plaque) in your arteries and inflammation are usually to blame for coronary artery disease.
When plaque builds up, it narrows your coronary arteries, decreasing blood flow to your heart. Eventually, the decreased blood flow may cause chest pain (angina), shortness of breath, or other coronary artery disease signs and symptoms. A complete blockage can cause a heart attack.
Because coronary artery disease often develops over decades, you might not notice a problem until you have a significant blockage or a heart attack. But there's plenty you can do to prevent and treat coronary artery disease. A healthy lifestyle can make a big impact.
If your coronary arteries narrow, they can't supply enough oxygen-rich blood to your heart — especially when it's beating hard, such as during exercise. At first, the decreased blood flow may not cause any coronary artery disease symptoms. As plaque continues to build up in your coronary arteries, however, you may develop coronary artery disease signs and symptoms, including:
Chest pain (angina). You may feel pressure or tightness in your chest, as if someone were standing on your chest. This pain, referred to as angina, usually occurs on the middle or left side of the chest. Angina is generally triggered by physical or emotional stress.
The pain usually goes away within minutes after stopping the stressful activity. In some people, especially women, this pain may be fleeting or sharp and felt in the neck, arm or back.
Heart attack. A completely blocked coronary artery will cause a heart attack. The classic signs and symptoms of a heart attack include crushing pressure in your chest and pain in your shoulder or arm, sometimes with shortness of breath and sweating.
Women are somewhat more likely than men are to experience less typical signs and symptoms of a heart attack, such as neck or jaw pain. Sometimes a heart attack occurs without any apparent signs or symptoms.
If you suspect you're having a heart attack, immediately call 911 or your local emergency number. If you don't have access to emergency medical services, have someone drive you to the nearest hospital. Drive yourself only as a last resort.
If you have risk factors for coronary artery disease — such as high blood pressure, high cholesterol, tobacco use, diabetes, a strong family history of heart disease or obesity — talk to your doctor. He or she may want to test you for the condition, especially if you have signs or symptoms of narrowed arteries.
Coronary artery disease is thought to begin with damage or injury to the inner layer of a coronary artery, sometimes as early as childhood. The damage may be caused by various factors, including:
Once the inner wall of an artery is damaged, fatty deposits (plaque) made of cholesterol and other cellular waste products tend to accumulate at the site of injury in a process called atherosclerosis. If the surface of the plaque breaks or ruptures, blood cells called platelets will clump at the site to try to repair the artery. This clump can block the artery, leading to a heart attack.
Atherosclerosis is a process in which blood, fats such as cholesterol and other substances build up on your artery walls. Eventually, deposits called plaques may form. The deposits may narrow or block your arteries. These plaques can also rupture, causing a blood clot.
Risk factors for coronary artery disease include:
Risk factors often occur in clusters and may build on one another, such as obesity leading to type 2 diabetes and high blood pressure. When grouped together, certain risk factors put you at an even greater risk of coronary artery disease. For example, metabolic syndrome — a cluster of conditions that includes elevated blood pressure, high triglycerides, low HDL, or "good," cholesterol, elevated insulin levels and excess body fat around the waist — increases the risk of coronary artery disease.
Sometimes coronary artery disease develops without any classic risk factors. Researchers are studying other possible factors, including:
Coronary artery disease can lead to:
The same lifestyle habits that can help treat coronary artery disease can also help prevent it from developing in the first place. Leading a healthy lifestyle can help keep your arteries strong and clear of plaque. To improve your heart health, you can:
The doctor will ask questions about your medical history, do a physical exam and order routine blood tests. He or she may suggest one or more diagnostic tests as well, including:
Electrocardiogram (ECG). An electrocardiogram records electrical signals as they travel through your heart. An ECG can often reveal evidence of a previous heart attack or one that's in progress.
In other cases, Holter monitoring may be recommended. With this type of ECG, you wear a portable monitor for 24 hours as you go about your normal activities. Certain abnormalities may indicate inadequate blood flow to your heart.
Echocardiogram. An echocardiogram uses sound waves to produce images of your heart. During an echocardiogram, your doctor can determine whether all parts of the heart wall are contributing normally to your heart's pumping activity.
Parts that move weakly may have been damaged during a heart attack or be receiving too little oxygen. This may indicate coronary artery disease or various other conditions.
Stress test. If your signs and symptoms occur most often during exercise, your doctor may ask you to walk on a treadmill or ride a stationary bike during an ECG. This is known as an exercise stress test. In some cases, medication to stimulate your heart may be used instead of exercise.
Some stress tests are done using an echocardiogram. For example, your doctor may do an ultrasound before and after you exercise on a treadmill or bike. Or your doctor may use medication to stimulate your heart during an echocardiogram.
Doctors may also use medications to stimulate your heart during an MRI. Doctors may use this imaging test to evaluate you for coronary artery disease.
Another stress test known as a nuclear stress test helps measure blood flow to your heart muscle at rest and during stress. It's similar to a routine exercise stress test but with images in addition to an ECG. A tracer is injected into your bloodstream, and special cameras can detect areas in your heart that receive less blood flow.
Cardiac catheterization and angiogram. To view blood flow through your heart, your doctor may inject a special dye into your coronary arteries. This is known as an angiogram. The dye is injected into the arteries of the heart through a long, thin, flexible tube (catheter) that is threaded through an artery, usually in the leg, to the arteries in the heart.
This procedure is called cardiac catheterization. The dye outlines narrow spots and blockages on the X-ray images. If you have a blockage that requires treatment, a balloon can be pushed through the catheter and inflated to improve the blood flow in your coronary arteries. A mesh tube (stent) may then be used to keep the dilated artery open.
Heart scan. Computerized tomography (CT) technologies can help your doctor see calcium deposits in your arteries that can narrow the arteries. If a substantial amount of calcium is discovered, coronary artery disease may be likely.
A CT coronary angiogram, in which you receive a contrast dye injected intravenously during a CT scan, also can generate images of your heart arteries.
Treatment for coronary artery disease usually involves lifestyle changes and, if necessary, drugs and certain medical procedures.
Making a commitment to the following healthy lifestyle changes can go a long way toward promoting healthier arteries:
Various drugs can be used to treat coronary artery disease, including:
Aspirin. Your doctor may recommend taking a daily aspirin or other blood thinner. This can reduce the tendency of your blood to clot, which may help prevent obstruction of your coronary arteries.
If you've had a heart attack, aspirin can help prevent future attacks. There are some cases where aspirin isn't appropriate, such as if you have a bleeding disorder or you're already taking another blood thinner, so ask your doctor before starting to take aspirin.
Sometimes more aggressive treatment is needed. Here are some options:
Your doctor inserts a long, thin tube (catheter) into the narrowed part of your artery. A wire with a deflated balloon is passed through the catheter to the narrowed area. The balloon is then inflated, compressing the deposits against your artery walls.
A stent is often left in the artery to help keep the artery open. Most stents slowly release medication to help keep the arteries open.
A surgeon creates a graft to bypass blocked coronary arteries using a vessel from another part of your body. This allows blood to flow around the blocked or narrowed coronary artery. Because this requires open-heart surgery, it's most often reserved for cases of multiple narrowed coronary arteries.
When placing a coronary artery stent, your doctor will find a blockage in your heart's arteries (A). A balloon on the tip of the catheter is inflated to widen the blocked artery, and a metal mesh stent is placed (B). After the stent is placed, the artery is held open by the stent, which allows blood to flow through the previously blocked artery (C).
Coronary bypass surgery is a procedure that restores blood flow to your heart muscle by diverting the flow of blood around a section of a blocked artery in your heart.
Lifestyle changes can help you prevent or slow the progression of coronary artery disease.
Eat healthy foods. A heart-healthy diet, such as the Mediterranean diet, that emphasizes plant-based foods, such as fruits, vegetables, whole grains, legumes and nuts — and is low in saturated fat, cholesterol and sodium — can help you control your weight, blood pressure and cholesterol. Eating one or two servings of fish a week also is beneficial.
Avoid saturated fat and trans fat, excess salt, and excess sugar. If you drink alcohol, drink it in moderation — this means up to one drink a day for women of all ages and men older than age 65, and up to two drinks a day for men age 65 and younger. One drink equals 12 ounces of beer, 5 ounces of wine or 1.5 ounces of 80-proof liquor.
In addition to healthy lifestyle changes, remember the importance of regular medical checkups. Some of the main risk factors for coronary artery disease — high cholesterol, high blood pressure and diabetes — have no symptoms in the early stages. Early detection and treatment can set the stage for a lifetime of better heart health.
Omega-3 fatty acids are a type of unsaturated fatty acid that's thought to reduce inflammation throughout the body, a contributing factor to coronary artery disease. However, some research has not found them to be beneficial. More research is needed.
Other supplements may help reduce your blood pressure or cholesterol level, two contributing factors to coronary artery disease. These include:
Early-stage coronary artery disease often produces no symptoms, so you may not discover you're at risk of the condition until a routine checkup reveals you have high cholesterol or high blood pressure. So it's important to have regular checkups.
If you know you have symptoms of or risk factors for coronary artery disease, you're likely to see your primary care doctor or a general practitioner. Eventually, however, you may be referred to a heart specialist (cardiologist).
Here's some information to help you get ready for your appointment and to know what to expect from your doctor.
Questions to ask your doctor at your initial appointment include:
Questions to ask if you are referred to a cardiologist include:
Don't hesitate to ask additional questions about your condition.
A doctor or cardiologist who sees you for heart-related signs and symptoms may ask:
It's never too early to make healthy lifestyle changes, such as quitting smoking, eating healthy foods and becoming more physically active. These are primary lines of defense against coronary artery disease and its complications, including heart attack and stroke.