Heart Attack and Unstable Angina

	Overview
	Health Tools
	FAQs
	Cause
	Symptoms
	What Increases Your Risk
	When to Call a Doctor
	Exams and Tests
	Treatment Overview
	Prevention
	Ongoing Concerns
	Life After a Heart Attack
	Medications
	Surgery
	Other Treatment
	End-of-Life Decisions
	Other Places To Get Help
	Related Information
	References
	Credits

What is a heart attack?

A heart attack occurs when blood flow to the heart is blocked. Without blood and the oxygen it carries, part of the heart starts to die. A heart attack doesn't have to be deadly. Quick treatment can restore blood flow to the heart and save your life.

Your doctor might call a heart attack a myocardial infarction, or MI.

What is angina, and why is unstable angina a concern?

Angina (say "ANN-juh-nuh" or "ann-JY-nuh") is a type of chest pain or discomfort that occurs when there is not enough blood flow to the heart. Angina can be dangerous, so it is important to pay attention to chest pain, know what is typical for you, learn how to control it, and understand when you need to get treatment.

There are two types of angina:

• Stable angina is chest pain that has a typical pattern. It happens when your heart is working harder and needs more oxygen, such as during exercise. The pain goes away when you rest.
• Unstable angina is chest pain that is unexpected, and resting or taking nitroglycerin may not help. Your doctor will probably diagnose unstable angina if you are having chest pain for the first time or if your pain is getting worse, lasting longer, happening more often, or happening at rest.

Unstable angina is a warning sign that a heart attack may happen soon, so it requires treatment right away. But if you have any type of chest pain, see your doctor.

What causes a heart attack?

Heart attacks happen when blood flow to the heart is blocked. This usually occurs because fatty deposits called plaque have built up inside the coronary arteries, which supply blood to the heart. If a plaque breaks open, the body tries to fix it by forming a clot around it. The clot can block the artery, preventing the flow of blood and oxygen to the heart. See a picture of how plaque causes a heart attack.

This process of plaque buildup in the coronary arteries is called coronary artery disease, or CAD. In many people, plaque begins to form in childhood and gradually builds up over a lifetime. Plaque deposits may limit blood flow to the heart and cause angina. But too often, a heart attack is the first sign of CAD.

Things like intense exercise, sudden strong emotion, or illegal drug use (such as a stimulant, like cocaine) can trigger a heart attack. But in many cases, there is no clear reason why heart attacks occur when they do.

What are the symptoms?

The most common symptom of a heart attack is severe chest pain.

• Many people describe the pain as discomfort, pressure, squeezing, or heaviness in the chest.
• People often put their fist to their chest when they describe the pain.
• The pain may spread down the left shoulder and arm and to other areas, such as the back, jaw, neck, or right arm.

Many people also have at least one other symptom, such as:

• Pain in the upper belly, often mistaken for heartburn.
• Sweating.
• Nausea and vomiting.
• Trouble breathing.
• A feeling that their heart is racing or pounding (palpitations).
• Feeling weak or very tired.
• Feeling dizzy or fainting.

Not everyone has the classic symptom of severe chest pain during a heart attack. Women, older adults, and people with diabetes are less likely to have severe chest pain and more likely to have shortness of breath, dizziness, weakness or fainting, and belly pain.

What should you do if you think you are having a heart attack?

If you have symptoms of a heart attack, act fast. Quick treatment could save your life.

If you are having chest pain and your doctor has prescribed nitroglycerin for angina:

1. Take 1 dose of nitroglycerin and wait 5 minutes.
2. If the chest pain doesn't improve or it gets worse, call 911 or other emergency services. Describe your symptoms, and say that you could be having a heart attack.
3. Stay on the phone. The emergency operator will tell you what to do.

If you are having chest pain and you do not have nitroglycerin:

1. Call 911 or other emergency services now. Describe your symptoms, and say that you could be having a heart attack.
2. Stay on the phone. The emergency operator will tell you what to do.
3. After you call for help, chew 1 regular-strength aspirin. Aspirin helps keep blood from clotting, so it may help you survive a heart attack.

The best choice is to go to the hospital in an ambulance. The paramedics can begin lifesaving treatments even before you arrive at the hospital. If you cannot reach emergency services, have someone drive you to the hospital right away. Do not drive yourself unless you have absolutely no other choice.

If you think you are having unstable angina but you are not sure, follow the steps listed above. Unstable angina can lead to a heart attack or death, so you need to have it checked right away.

How is a heart attack treated?

If you go to the hospital in an ambulance, treatment will be started right away to restore blood flow and limit damage to the heart. You may be given medicines, including:

• Aspirin (if you have not already taken some) and other medicines to prevent blood clots.
• Medicines that break up blood clots (thrombolytics). To work, these must be given within a few hours of the start of the heart attack.
• Medicines to decrease the heart's workload, ease pain, and treat abnormal heart rhythms, which can be life-threatening.

At the hospital, you will have tests, such as:

• Electrocardiogram (EKG or ECG). An EKG can detect signs of poor blood flow, heart muscle damage, abnormal heartbeats, and other heart problems.
• Blood tests, including tests to see whether cardiac enzymes are high. Having these enzymes in the blood is usually a sign that the heart has been damaged.

If these tests show that you may be having a heart attack, you may have a cardiac catheterization. For this test, the doctor puts a thin, flexible tube (called a catheter) through an artery in the groin or arm and carefully guides it into the heart. (See a picture of catheter placement.) A dye is injected that makes the coronary arteries show up on a computer screen. The doctor then can see if the coronary arteries are blocked and how your heart is working.

If cardiac catheterization shows that an artery is blocked, the doctor may do angioplasty right away. The doctor guides the catheter into the narrowed artery, and a small balloon at the end of it is inflated. This widens the artery to help restore blood flow. Often a small wire-mesh tube called a stent is placed to keep the artery open. See a picture of angioplasty with stent placement.

Angioplasty, with or without a stent, is the preferred treatment for a heart attack. But if angioplasty is not available or cannot be done for some reason, “clot-busting” thrombolytic medicines may be used. Or the doctor may do emergency bypass surgery to redirect blood around the blocked artery.

After these treatments, medicines are given to prevent clots, reduce the heart’s workload, and lower cholesterol. These can help prevent another heart attack and heart failure. Most people who have had a heart attack take these and sometimes other medicines for the rest of their lives.

After you have had a heart attack, the chance that you will have another one is higher. Taking part in a cardiac rehab program helps lower this risk. A cardiac rehab program is designed for you and supervised by doctors and other specialists. It can help you learn how to eat a balanced diet and exercise safely to reduce your risk of more heart problems.

It is common to feel worried and afraid after a heart attack. But if you are feeling very sad or hopeless, ask your doctor about treatment. Getting treatment for depression may help you recover from a heart attack.

Can you prevent a heart attack?

Heart attacks are usually the result of heart disease, so taking steps to delay or reverse coronary artery disease can help prevent a heart attack. Heart disease is the number one killer of both men and women in the United States, so these steps are important for everyone.

To improve your heart health:

• Don't smoke, and avoid secondhand smoke. Quitting smoking can quickly reduce the risk of another heart attack or death.
• Eat a heart-healthy diet that includes plenty of fish, fruits, vegetables, beans, high-fiber grains and breads, and olive oil.
• Get regular exercise on most, preferably all, days of the week. Your doctor can suggest a safe level of exercise for you.
• Control your cholesterol and blood pressure.
• If you have diabetes, keep your blood sugar as close to normal as possible.
• Lower your stress level. Stress can damage your heart.
• Take a daily aspirin if your doctor advises it.
• Get a flu shot every year.
• Take all of your medicines correctly. Taking medicine can lower your risk of having another heart attack or dying from coronary artery disease.

Health tools help you make wise health decisions or take action to improve your health.

	Decision Points focus on key medical care decisions that are important to many health problems.
	Should I receive CPR and mechanical ventilation?
	Actionsets are designed to help people take an active role in managing a health condition.
	Eating a heart-healthy diet
	Eating a steady amount of vitamin K when you take warfarin (Coumadin)
	Exercising for a healthy heart
	Living with a pacemaker or ICD
	Tips for following the Dietary Approaches to Stop Hypertension (DASH) diet
	Interactive tools are designed to help people determine health risks, ideal weight, target heart rate, and more.
	Interactive Tool: Are You at Risk for a Heart Attack?

The major cause of unstable angina and heart attack is coronary artery disease (CAD). Coronary artery disease occurs when plaque builds up over years inside your coronary arteries and reduces blood flow to the heart muscle. In many people, coronary artery disease begins in adolescence and gradually develops over a lifetime.

High cholesterol, high blood pressure, and smoking damage your arteries and contribute to plaque buildup. The process of plaque buildup in the arteries is called atherosclerosis. See pictures of atherosclerosis and how high blood pressure damages arteries.

Plaques are deposits of cholesterol, calcium, and other substances that are covered by a fibrous cap. If a sudden surge in blood pressure occurs, if the artery suddenly constricts, or if other factors such as inflammation are present, the fibrous cap can tear or rupture. The body tries to repair the tear, much as it might stop bleeding from a cut on the skin, by forming a blood clot over it. The blood clot can completely block blood flow through the coronary artery to the heart muscle and cause a heart attack. See a picture of how plaque causes a heart attack.

Newly formed plaques are most at risk for rupture. The fibrous caps on newly formed plaques tend to be more unstable and more prone to tearing than the thicker fibrous caps on plaques that have been present for a long period of time.

But plaque is not always the cause of a heart attack. In rare cases, the coronary artery spasms and contracts, obstructing blood flow and causing chest pain. If severe, the spasm can completely block blood flow and cause a heart attack. Most of the time in these cases, atherosclerosis is also involved, although sometimes the arteries are clear. Cocaine, cold weather, emotional stress, and other factors can cause these spasms. But in many other cases, it is not known what triggers the spasm.

A blood clot that forms over a ruptured plaque may not completely block the artery but may block blood flow enough to cause unstable angina. Unstable angina is a sign that a heart attack may soon follow, because the blood clot can quickly grow and block the artery. If the blood clot dissolves, and an immediate heart attack is avoided, the body will try over time to repair the tear on the surface of the plaque. But this newly repaired plaque can also be very unstable. It is more likely to rupture again, putting you at even greater risk of a heart attack.

Heart attack triggers

In most cases, there are no clear reasons why heart attacks occur when they do. But sometimes your body releases adrenaline and other hormones into the bloodstream in response to intense emotions such as anger, fear, and the "fight or flight" impulse. Heavy physical exercise, emotional stress, lack of sleep, and overeating can also trigger this response. Adrenaline increases blood pressure and heart rate and can cause coronary arteries to constrict, which may cause an unstable plaque to rupture.

Nicotine, which is found in tobacco products, and cocaine can cause similar responses.

The most common symptom of a heart attack is severe chest pain, although this sensation is not always present. In one study of people treated for a heart attack, almost half of them came to the emergency room because they had symptoms other than chest pain. These symptoms included shortness of breath, dizziness, weakness or fainting, and abdominal pain.¹Women, older adults, and people with diabetes are less likely to have chest pain during a heart attack and more likely to have other symptoms.

It is possible to have a "silent heart attack" without any symptoms, but this is rare. Most people have chest pain and at least one other symptom, such as:

• A feeling of choking or a "tight throat," a lump in the throat, or a need to keep swallowing.
• A cold sweat.
• Nausea.
• A sense of impending doom.
• Difficulty breathing or breathlessness.
• Palpitations, or feeling your heart beat rapidly or irregularly. (Palpitations are very common and are usually harmless in a healthy heart, but they may signal coronary artery disease if brought on by exertion.)
• Numbness or discomfort in either arm or hand.
• Weakness.

People who are having a heart attack often describe their chest pain in various ways. The pain:

• May feel like pressure, heaviness, weight, tightness, squeezing, discomfort, burning, a sharp ache (less common), or a dull ache. People often put their fist to their chest when describing the pain.
• May radiate from the chest down the left shoulder and arm (the most common site) and also to other areas, including the left shoulder, middle of the back, upper portion of the abdomen, right arm, neck, and jaw. See a picture of the areas where you might have pain during a heart attack.
• May be diffuse—the exact location of the pain is usually difficult to point out.
• Is not made worse by taking a deep breath or pressing on the chest.
• Usually begins at a low level, then gradually increases over several minutes to a peak. The discomfort may come and go. Chest pain that reaches its maximum intensity within seconds may represent another serious problem, such as an aortic aneurysm.

Women are more likely to have symptoms such as shortness of breath, heartburn, nausea, jaw pain, back pain, or fatigue.

Call 911 or your local emergency services if:

• Your chest pain gets worse or lasts more than 5 minutes, especially if you are short of breath or feel weak, nauseated, or lightheaded.
• Your chest pain doesn't improve or gets worse within 5 minutes after taking 1 dose of nitroglycerin.

It may not always be possible to tell the difference between unstable angina and a heart attack. Often the symptoms are similar. Both conditions require immediate emergency care.

People who have unstable angina often describe their pain as:

• Starting within the past 2 months and becoming more severe.
• Limiting their physical activity.
• Suddenly becoming more frequent, severe, or longer-lasting or being brought on by less exertion than before.
• Occurring at rest with no obvious exertion or stress—it may wake the person up.
• Not responding to rest or nitroglycerin.

The symptoms of stable angina are different from those of unstable angina. Stable angina occurs at predictable times with a specific amount of exertion or activity and may continue without much change for years. It is relieved by rest or nitrates (nitroglycerin) and usually lasts less than 5 minutes.

Coronary artery disease (CAD) is the major cause of heart attacks. Therefore, the more risk factors you have for CAD, the greater your risk for developing unstable angina or having a heart attack. Smoking, diabetes, high cholesterol, high blood pressure, and a family history of heart disease are all strong risk factors for coronary artery disease. For more information, see the What Increases Your Risk section of the topic Coronary Artery Disease.

Use the heart attack risk calculator to estimate your risk of having a heart attack over 10 years. This tool is designed to estimate risk in adults age 20 and older who do not have heart disease or diabetes.

Even if you already have coronary artery disease or have had a heart attack, you can still lower your risk of another heart attack. To lower your risk:

• Stop smoking. Quitting smoking is probably the most important step to decrease your chance of a heart attack. Avoid secondhand smoke too.
• Reduce high cholesterol. High cholesterol can lead to a buildup of cholesterol inside your arteries.
• Lower high blood pressure. High blood pressure damages the coronary arteries and increases the heart's workload.
• Manage diabetes. People who have diabetes develop hardening and narrowing of the arteries more frequently and at a younger age than those not affected by diabetes. Keeping blood sugar at normal levels can slow this development.
• Stay at a healthy weight. Weight loss frequently improves blood pressure and cholesterol levels and may also help control diabetes.
• Be physically active. Regular exercise can help reduce your risk of heart attack by helping you to control cholesterol and blood pressure, regulate blood sugar (important for people with diabetes), and lose weight. Try to do activities that raise your heart rate. Exercise for at least 30 minutes on most, preferably all, days of the week.
• Manage depression and emotions. Treating depression and treating anger problems are important steps in improving cardiac and overall health and quality of life.
• Reduce stress. Stress causes increased blood pressure and heart rate and causes your arteries to narrow, increasing your risk for heart attack.
• Evaluate birth control pill and hormone replacement therapy use. Birth control pills are more likely to increase a woman's risk if she is older than 35 and smokes cigarettes. Hormone therapy (estrogen with or without progestin) may increase the risk for heart disease. This risk is higher for some women than others.
• Take an aspirin every day (check with your doctor first to make sure you have no medical reasons for not taking it).
• Avoid getting sick from the flu. Get a flu shot every year.
• Take all of your medicines correctly. Taking medicine can lower your risk of having another heart attack or dying from coronary artery disease.

Some risk factors are beyond your control. These include:

• A family history of heart disease, especially if heart disease occurred in males younger than 55 and females younger than 65.
• Your age and gender. The number of people affected by heart disease increases with age in men after age 45 and in women after age 55. Also, men and women have different risk factors.

Elevated homocysteine levels and mutations of a specific gene (MTHFR) may also indicate an increased risk of heart attack, although more study is needed to fully understand their role in heart disease. Tests for these factors may be indicated for some people, such as those who have had a heart attack at a young age, but are not recommended for the general population.

Elevated levels of C-reactive protein (CRP), a substance found in blood that indicates inflammation, may better predict your risk for having a heart attack than cholesterol levels. Two studies on CRP levels and statin treatment show that testing CRP levels may help predict heart attack risk even when a person has a normal or low level of LDL cholesterol. The studies suggest that testing people for both C-reactive protein and cholesterol levels could prevent more heart attacks by identifying who is at risk.^{2, 3}

Tests for C-reactive protein are now available in many hospitals. If you have any CAD risk factors, ask your doctor if CRP testing would be helpful in guiding your treatment.

Most nonsteroidal anti-inflammatory drugs (NSAIDs), which are used to relieve pain and fever and reduce swelling and inflammation, may increase the risk of heart attack. This risk is greater if you take NSAIDs at higher doses or for long periods of time. People who are older than 65 or who have existing heart, stomach, or intestinal disease are more likely to have problems.

Aspirin, unlike other NSAIDs, has been shown to reduce the risk of heart attack and stroke. But it also carries the risks of serious stomach and intestinal bleeding as well as skin reactions. Regular use of other NSAIDs, such as ibuprofen, may make aspirin less effective in preventing heart attack and stroke.

Call 911 or other emergency services immediately if you have any of the following symptoms of a heart attack:

• You have chest pain that has not improved or that gets worse within 5 minutes after taking 1 dose of nitroglycerin and/or resting. After you call 911 , continue to stay on the phone with the emergency operator. He or she will give you further instructions. See how to take nitroglycerin.
• You have chest pain or discomfort that is crushing or squeezing, feels like pressure on the chest, and gets worse or lasts more than 5 minutes, especially if it occurs with any of the following symptoms:
  • Sweating
  • Shortness of breath
  • Nausea or vomiting
  • Pain that spreads from the chest to the neck, the jaw, or one or both shoulders or arms
  • Dizziness or lightheadedness
  • A fast or irregular pulse
  • Signs of shock

Women are more likely to have symptoms such as shortness of breath, heartburn, nausea, jaw pain, back pain, or fatigue.

After you call 911 or other emergency services, you should chew 1 regular-strength aspirin (325 mg) unless you cannot take aspirin because of allergy or some other reason. By calling 911 and taking an ambulance to the hospital, you may be able to start treatment before you arrive at the hospital. If any complications occur along the way, ambulance personnel are trained to evaluate and treat them.

If an ambulance is not readily available, have someone else drive you to the emergency room. Do not drive yourself to the hospital.

If you witness a person become unconscious, call 911 or other emergency services and start CPR (cardiopulmonary resuscitation). The emergency operator can coach you on how to perform CPR. To learn more about CPR, see the Rescue Breathing and Cardiopulmonary Resuscitation (CPR) section of the topic Dealing With Emergencies.

Never wait if you have symptoms of a heart attack. Many people are unsure if they are having a heart attack and take a "wait and see" approach. Heart attack symptoms can vary. People often discount their symptoms if they do not fit into the expected "extreme chest pain" scenario. Some people are embarrassed or don't want to bother others by calling for help if they think it may not be a heart attack. Even if you're not sure it's a heart attack, you should still have it checked out. Rapid treatment can save your life.

Who to See

You will be evaluated and treated by an emergency medicine specialist in the emergency room. For ongoing care, you will likely see a cardiologist. If surgery is needed, you will be referred to a cardiovascular surgeon.

Emergency evaluation for a heart attack

After you call 911 for a heart attack, paramedics will quickly assess your heart rate, blood pressure, and breathing rate and place electrodes on your chest for an electrocardiogram (EKG, ECG). An electrocardiogram is a graphic record of the heart's electrical activity as it contracts and relaxes. The ECG's jagged-line image appears on a portable monitor, and in some areas this image can be transmitted to the hospital emergency room so a doctor there can assess your condition before you arrive.

When you arrive at the hospital, the emergency room doctor will take your history and perform a physical exam, and a more complete ECG will be done. An ECG can detect signs of insufficient blood flow, heart muscle damage, abnormal heartbeats, and other heart problems. A technician will draw blood to test for cardiac enzymes, which are released into the bloodstream when heart cells die. The presence of the protein troponin in the blood usually means that there has been heart damage.

Results of these tests are usually available quickly. If your tests show that you are at risk of having or are having a heart attack, your doctor will probably recommend that you have cardiac catheterization. During a cardiac catheterization, a fine tube (called a catheter) is threaded through an artery in your arm or leg and up into the heart. Then a dye that contains iodine is injected, which makes the coronary arteries visible on a digital X-ray screen. The doctor can then see whether your coronary arteries are blocked and how your heart functions.

If an artery appears blocked, angioplasty with stent placement, a procedure to open up clogged arteries, may be done during the catheterization, or you will be referred to a cardiovascular surgeon for coronary artery bypass graft surgery.

If your tests do not clearly indicate a heart attack or unstable angina and you do not have other high-risk indicators (such as a previous heart attack), you will probably have other tests, such as a myocardial perfusion scan, also called single photon emission computed tomography or SPECT imaging. SPECT is a noninvasive imaging scan that is often done while you are in the emergency department to help determine whether you are at risk of heart attack.⁴

If your SPECT test is abnormal, you are considered at high risk and may need cardiac catheterization.

If your tests do not indicate a heart attack but your doctor thinks you have unstable angina and may be in danger of having a heart attack, you will be admitted to the hospital.

Testing after a heart attack

From 2 to 3 days after a heart attack or after being admitted to the hospital for unstable angina, you may have additional tests to assess how well your heart is working and to determine whether undamaged areas of the heart are still receiving adequate blood flow.

These tests may include:

• Echocardiogram (echo). An echo is an ultrasound exam used to evaluate the size, thickness, shape, and movement of the heart muscle. It also evaluates blood flow and the heart valves.
• Stress electrocardiogram (such as treadmill testing). A stress test compares your ECG while you rest to your ECG after your heart has been stressed, either through physical exercise (treadmill or bike) or by using a medicine. A stress test can detect ischemia, which is reduced blood flow to the heart muscle.
• Stress echocardiogram. A stress echocardiogram can determine whether you may have reduced blood flow to the heart.
• Cardiac perfusion scan. A thallium scan or technetium scan (also called a sestamibi scan) is a test used to estimate the amount of blood reaching the heart muscle during rest and exercise.
• Angiogram. In this test, a dye (contrast material) is injected into the coronary arteries to evaluate your heart and coronary arteries.

When a heart attack is in progress, you need to act quickly. Prompt treatment with medicines, angioplasty combined with stenting, or surgery to restore blood flow soon after symptoms first begin can prevent permanent injury to the heart muscle and save your life.

Initial treatment

If you are having a heart attack, the goal of your health care team will be to prevent permanent heart muscle damage by restoring blood flow to your heart as quickly as possible. If you are transported to the hospital in an ambulance, you will be given oxygen therapy and probably nitroglycerin or a pain reliever, such as morphine.

Additionally, aspirin (which is usually chewed on the way to the hospital or in the emergency room), heparin, and other antiplatelet drugs are given to prevent clots from growing. Other medicines will be given initially to decrease your heart's workload, improve its pumping function, and treat life-threatening abnormal heartbeats if they occur.

The time it takes to get to a hospital is critical because angioplasty and/or stenting to open blocked arteries or "clot-busting" thrombolytic medicines to dissolve clots are most effective if used within the first several hours after symptoms start. Thrombolytics are given through an intravenous (IV) line and travel to the coronary arteries where they break up clots.

Numerous studies have shown that percutaneous coronary intervention (angioplasty with or without stenting) saves lives—20 lives for every 1,000 people treated—when compared with treatment with thrombolytics.⁵ But experts do not know yet how safe the drug-eluting stents are over the long term or how well they work over the long term.

Although angioplasty with or without stenting is usually the preferred treatment, it is not available at all hospitals. As a result, some communities are training paramedics to identify people who have signs of heart attack so that they can be transported directly to a heart center, even if it means bypassing a closer hospital.

If you are treated at a hospital that has proper equipment and staff, you may be taken to the cardiac catheterization lab where your doctor will evaluate your coronary arteries to determine whether angioplasty or coronary artery bypass graft surgery is appropriate.

If angioplasty with or without stenting is not possible, either because of the location of the blockage or because of numerous blockages, emergency coronary artery bypass surgery may be done.

If you are having unstable angina, you most likely will be admitted to the hospital and given medicines, including aspirin, other antiplatelet medicines, and heparin. You will be closely monitored and tested. If chest pain continues after the above treatment and you are at high risk for heart attack, your doctor may decide to perform coronary catheterization and plan for possible angioplasty and stent placement to prevent a heart attack.⁶

Ongoing treatment

After you have had a heart attack, you will stay in the hospital for at least a few days so your heart rate and rhythm, blood pressure, and medicines can be closely monitored. You will also have several electrocardiograms. This is because after a heart attack you are at high risk of having serious complications, such as life-threatening abnormal heart rhythms and heart failure.

Medicines are started to reduce the risk of developing complications. Angiotensin-converting enzyme (ACE) inhibitors and beta-blockers can help prevent heart failure and abnormal heartbeats (arrhythmias), both of which can develop after a heart attack. These medicines also improve your chance of survival after a heart attack.

Cholesterol-lowering medicines called statins are usually given to lower your LDL cholesterol level to less than 100 mg/dL.⁷ Studies show that taking a cholesterol-lowering medicine substantially decreased the risk of heart attack and stroke over a 5-year period in high-risk individuals, such as those who have had a heart attack.⁸

Aspirin, other antiplatelet medicines such as clopidogrel (Plavix), or anticoagulants (such as warfarin) may be used after a heart attack. These medicines are used to lower the risk of another heart attack and to prevent blood clots from forming in the heart, which could break loose and travel to the brain, causing a stroke. If you take warfarin (Coumadin), see:

Eating a steady amount of vitamin K when you take warfarin (Coumadin).

The amount of heart muscle that is permanently damaged may be less than it appears immediately after a heart attack has occurred. Some heart tissue may be "stunned myocardium," or heart muscle that is not able to contract normally at first but is later able to function normally. Your heart's pumping capacity will be closely monitored and your treatment adjusted as needed during this time.

Research highlights the importance of quitting smoking after a heart attack. People who continue to smoke after a heart attack are 1½ times more likely than nonsmokers to have another heart attack. Among those who stop smoking, the risk decreases gradually over 36 months until it becomes the same as the risk for nonsmokers.⁹

If you smoke, your doctor will strongly advise that you quit and avoid secondhand smoke too. Your doctor may prescribe medicine and therapy to help you do so. Studies show that nicotine replacement therapy, use of the medicine bupropion (such as Zyban or Wellbutrin), and supportive therapy significantly increase long-term success in quitting.¹⁰ For more information on how to quit, see the topic Quitting Tobacco Use.

Your doctor may talk to you about other lifestyle changes you may need to make, such as exercising or eating a low-fat diet. You may begin a cardiac rehabilitation program while you're still in the hospital. For more information, see the topic Cardiac Rehabilitation.

Avoid getting sick from the flu. Get a flu shot every year.

Treatment if the condition gets worse

Heart attacks that damage crucial or large areas of the heart tend to cause more complications later. If only a small amount of heart muscle dies, the heart may still function normally after a heart attack.

Scar tissue eventually replaces the areas of heart muscle tissue that are damaged by a heart attack. Scar tissue limits your heart's ability to pump effectively. Damage to the left ventricle can limit the heart's capacity to pump. This damage can lead to heart failure.

If the heart attack damaged the area of your heart that regulates your heart rate, your heart can develop abnormal heart rhythms, called arrhythmias. In this case, you may need a pacemaker, which is a device that stimulates the heart to beat and regulates the heart rate, and possibly medicines to control your heart rhythms.¹¹ Some arrhythmias also increase your risk for stroke.

The chance that these complications will develop depends on the amount of heart tissue affected by a heart attack and whether medicines are given during and after a heart attack to help prevent these complications. Other factors, such as your age and general health, also determine your risk of complications and death.

After a heart attack, you may be a candidate for cardiac rehabilitation to lower your risk of death related to heart disease. Rehabilitation and lifestyle changes are an important part of your recovery after a heart attack. For more information, see the topic Cardiac Rehabilitation.

If you do not participate in a cardiac rehabilitation program, you will still need to learn about necessary lifestyle changes, such as quitting smoking, eating a low-fat diet, and perhaps starting an exercise program.

Palliative care

If your condition gets worse, you may want to think about palliative care. Palliative care is a kind of care for people who have illnesses that do not go away and often get worse over time. It is different than care to cure your illness, called curative treatment. Palliative care focuses on improving your quality of life—not just in your body, but also in your mind and spirit. Some people combine palliative care with curative care.

Palliative care may help you manage symptoms or side effects from treatment. It could also help you cope with your feelings about living with a long-term illness, make future plans around your medical care, or help your family better understand your illness and how to support you.

If you are interested in palliative care, talk to your doctor. He or she may be able to manage your care or refer you to a doctor who specializes in this type of care.

For more information, see the topic Palliative Care.

The percentage of Americans who have a heart attack, as well as the number of resulting deaths, has continued to decrease since the 1970s. This decline is mainly attributed to the steps people are taking to prevent coronary artery disease (CAD) and heart attack, including lowering blood pressure and cholesterol and changing diet and exercise habits.¹²

The most important lifestyle changes that you can make are to quit smoking and to exercise on most, preferably all, days of the week. Eating a balanced diet that is low in saturated fats and rich in fruits and vegetables is also advised.

Lifestyle changes may include:

• Quitting smoking and avoiding secondhand smoke.
• Controlling your cholesterol.
• Controlling your blood pressure.
• Exercising.
• Relaxing and reducing stress.
• Managing depression and anger.
• Getting a flu shot every year.

General dietary guidelines for heart-healthy eating may be recommended, such as the:

• Therapeutic Lifestyle Changes (TLC) diet.¹³ For more information on this diet, see:
  • The nutrient composition of the TLC diet.
  • Tips for success with the TLC diet.
  • Sample menu for the TLC diet.
• American Heart Association healthy diet guidelines.
• Mediterranean diet.

Specific dietary considerations involve:

• Antioxidants and heart disease.
• Fish and heart disease.
• Fiber's effect on cholesterol.
• Soy's effect on cholesterol.
• Alcohol and heart disease.
• B vitamins. Doctors recommend eating a balanced diet that includes plenty of vitamins B6, B12, and folic acid. These vitamins can reduce homocysteine levels. (People with high homocysteine levels can be at increased risk for heart attack.) But vitamin B and folic acid supplements have not been shown to reduce the risk of a heart attack.^{14, 15}
• Cholesterol-lowering margarines.
• Trans fat and heart disease.

Cholesterol

Having high cholesterol increases your risk of coronary artery disease. If diet and exercise are not effective in lowering your cholesterol to a safe level, your doctor will probably prescribe a statin, a cholesterol-lowering medicine. These medicines have been proven effective in treating high cholesterol, and now doctors are beginning to prescribe them for people with lower cholesterol levels. Recent studies show that the use of cholesterol-lowering drugs can also help people with normal to moderately high levels of cholesterol. In these people, cholesterol-lowering drugs combined with lifestyle changes may slow the development of atherosclerosis and lower the risk of heart attack or death.

Aspirin

Aspirin may reduce the risk of developing blood clots that can lead to a heart attack in people with known CAD and in people with multiple risk factors for CAD, such as diabetes, high blood pressure, and high cholesterol. There are some risks associated with aspirin therapy that you should discuss with your doctor before you begin this type of treatment. If you cannot take aspirin, your doctor may prescribe another antiplatelet medicine, such as clopidogrel (Plavix).

Hormone therapy

Taking estrogen with or without progestin does not prevent coronary artery disease. In fact, if you are 10 or more years past menopause, taking hormone therapy may raise your risk of coronary artery disease.¹⁶

Talk to your doctor about your risks with hormone therapy. And carefully weigh the benefits against the risks of taking it. If you need relief for symptoms of menopause, hormone therapy is one choice you can think about. But there are other types of treatment for problems like hot flashes and sleep problems. For more information, see the topic Menopause and Perimenopause.

After you've had a heart attack, your biggest concern will probably be that you could have another one. Taking your medicines as directed will be an important part of preventing another heart attack. Medicines commonly prescribed after a heart attack include drugs to:

• Prevent blood clots.
• Decrease the work of your heart.
• Improve your heart’s pumping ability.
• Lower cholesterol.
• Treat irregular heartbeats.
• Lower blood pressure.

Understanding what coronary artery disease (CAD) is and how to treat it may help prevent a future heart attack. For more information, see the topic Coronary Artery Disease.

Your doctor will want to closely monitor you after a heart attack. Be sure to keep all your appointments. Tell your doctor about any changes in your condition, such as changes in chest pain, weight gain or loss, shortness of breath with or without exercise, and feelings of depression.

About half of all people who have a heart attack will experience a serious complication. The kinds of complications you may have depend upon the location and extent of the heart muscle damage. The most common complications are:

• Abnormal heart rhythms, called arrhythmias. These include life-threatening ventricular tachycardia, which is a rapid heart rate, and atrial fibrillation, a type of irregular heartbeat.
• Heart failure, which can be short-term or can become a lifelong condition.

Managing angina

You should notify your doctor about any chest pain or discomfort (angina) you have after a heart attack, because it will probably be treated more aggressively and may indicate that you are at risk for another heart attack. Many people have stable angina, which is predictable and diminishes after taking nitroglycerin (a medicine to control angina) and resting.

Nitroglycerin is often prescribed to be taken on an as-needed basis for angina. In most cases, you may take 1 nitroglycerin tablet or 1 dose if you use the spray form. If after 5 minutes the chest pain doesn't improve or gets worse, call 911 or other emergency services immediately. Continue to stay on the phone with the emergency operator—he or she will give you further instructions.

See how to use and store nitroglycerin. Keep nitroglycerin with you at all times. Some doctors recommend that you use it before you exercise or exert yourself, to prevent an angina attack.

Coming home after a heart attack may be unsettling. Your hospital stay may have seemed too short. You may be nervous about being home without medical oversight after being so closely attended to in the hospital. But you have undergone tests that tell your doctor that it is safe for you to return home. Also, to reduce your risk of having another heart attack, your doctor may recommend that you:

• Quit smoking and avoid secondhand smoke. Quitting smoking may be the most important step you can take to reduce your risk. Evidence suggests that people with coronary artery disease who stop smoking rapidly reduce their risk of recurrent heart attack or death. Check with your doctor about using nicotine replacement therapy. Nicotine replacement therapy, use of the medicine bupropion (such as Zyban or Wellbutrin), and supportive therapy significantly increase long-term success in quitting.¹⁰ For more information, see the topic Quitting Tobacco Use.
• Be physically active. Talk with your doctor about exercising safely and about enrolling in a cardiac rehabilitation program. Regular exercise can help reduce your risk of another heart attack by helping you control cholesterol and blood pressure, regulate blood sugar (important for people with diabetes), and lose weight. See the Cardiac Rehabilitation topic.
• Take an aspirin every day. If you have a stent, you may also take an antiplatelet medicine, such as clopidogrel (Plavix).
• Lower your cholesterol by taking medicines such as statins or other lipid-lowering medicines.¹⁷ Several studies have shown that lowering cholesterol can reduce the risk for another heart attack.
• Control your blood pressure by taking medicines as directed by your health professional. Some nutrients in the diet can affect blood pressure. See nutrition for hypertension (including the DASH diet) for more information about this eating plan, which has been proven to lower blood pressure.
• Keep your blood sugar under control if you have diabetes. Studies have found that having high blood sugar over a long period of time is linked with developing heart disease.¹⁸ One way to check whether your blood sugar is under control is to have a simple blood test (called a hemoglobin A1c test) every 2 to 3 months. The American Diabetes Association and the American Heart Association recommend that people with diabetes have an HA1c level of less than 7%.¹⁹
• Follow a heart-healthy diet. A heart-healthy diet includes eating more fish. You may also follow the Mediterranean diet. A heart-healthy diet may help you lose weight, lower your blood pressure, and reduce your cholesterol. Studies show that people who follow these dietary practices may live longer.¹⁷ For more information, see:

  Eating a heart-healthy diet.

• Reduce stress. Some evidence suggests that stress management may decrease rates of heart attack or death in people with coronary artery disease.¹⁷
• Participate in a cardiac rehabilitation program. You will learn how to exercise safely, change habits that put you at risk for another heart attack, and deal with stress and emotional issues. Studies have found that cardiac rehab reduces your risk of having another heart attack.¹⁷ Try to do activities that raise your heart rate. Exercise for at least 30 minutes on most, preferably all, days of the week.
• Avoid getting sick from the flu. Get a flu shot every year.
• If you drink alcohol, drink moderately (1 alcoholic drink per day for women or 2 drinks per day for men). Drinking alcohol moderately may lower your risk of complications after a heart attack.²⁰ Drinking alcohol moderately, along with living a healthy lifestyle, may lower your risk for a heart attack.²¹ Although studies show that wine may be beneficial, the American Heart Association (AHA) states that the link between wine and reduced coronary artery disease has not been proven. The AHA urges individuals to talk to their doctors about the benefits and risks of drinking alcoholic beverages.²²
• Confide in loved ones. Having a heart attack is scary, and depression afterward is common. Asking for and receiving support from friends and relatives can help you avoid depression. If you continue to have the "blues" after your heart attack, talk to your doctor about counseling and medicine for depression. A study showed that people who received treatment for depression recovered better after a heart attack than those who did not. (However, long-term survival was not affected.)²³

Before you start an exercise program or do any strenuous exercise, your doctor can do pre-exercise testing to determine your risk for heart attack. For more information, see the following:

Exercising for a healthy heart

One common myth is that resuming sex after a heart attack can cause another heart attack, stroke, or sudden death. According to the American Heart Association, people who have had heart attacks can resume sexual activity after a heart attack as soon as they feel ready for it. Talk with your doctor if you have any concerns.

Most often the underlying cause of a heart attack is coronary artery disease (CAD). Understanding what CAD is and how to treat it may help prevent a future heart attack. For more information, see the topic Coronary Artery Disease.

Medicines for unstable angina

Certain medicines can help keep blood from clotting, reduce the risk that unstable angina may develop into a heart attack, and decrease your chance of dying. These include:

• Aspirin.
• Antiplatelet medicines, such as clopidogrel (Plavix).
• Anticoagulants, such as heparin, enoxaparin (Lovenox), dalteparin (Fragmin), and bivalirudin (Angiomax). Some anticoagulants, such as bivalirudin, are only used in the hospital.

Medicines that decrease the heart's workload, improve blood flow to the heart, and relieve chest pain are usually given to people with unstable angina who are at risk of heart attack. These medicines include:

• Morphine.
• Nitrates, such as nitroglycerin or isosorbide dinitrate (for example, Isordil).
• Beta-blockers, such as carvedilol (Coreg) or metoprolol (for example, Lopressor).

In some cases, additional medicines may be used, including:

• Glycoprotein IIb/IIIa inhibitors, which help prevent clotting. These medicines are only used in the hospital, such as during a heart attack or after an angioplasty.
• Calcium channel blockers, which are used when beta-blockers cannot be taken.
• Angiotensin-converting enzyme (ACE) inhibitors, which are used to control high blood pressure and reduce the heart's workload.
• Insulin, which is used to help control high blood sugar.

Medicines for a heart attack in progress

Medicines for a heart attack work to open the blocked artery to restore blood flow as fast as possible and to decrease the workload on the heart.

• Aspirin and other antiplatelet medicines, anticoagulants (such as heparin), glycoprotein IIb/IIIa inhibitors (if angioplasty is needed), and especially "clot-busting" thrombolytics all work to open clogged arteries. Thrombolytics virtually break up clots by dissolving them, and the other medicines prevent clots from enlarging.
• Oxygen therapy, nitrates (such as nitroglycerin), and beta-blockers work to decrease the workload on the heart, thereby decreasing the amount of oxygen needed and possibly saving heart muscle.

Medicines after a heart attack

After a heart attack, your doctor may give you medicines to prevent heart failure and prevent or reduce the risk of irregular heartbeats (arrhythmias), both of which can happen after a heart attack. These medicines include:

• ACE inhibitors, which lower blood pressure and lower the heart's workload.
• Beta-blockers, which improve blood flow to the heart and lower the heart's workload.

Your doctor may also give you medicines to prevent blood clots from forming and causing a stroke or another heart attack. These medicines include:

• Aspirin.
• Antiplatelet medicines.
• Anticoagulants. If you take the anticoagulant warfarin (Coumadin), see:

  Eating a steady amount of vitamin K when you take warfarin (Coumadin).

If you have high cholesterol, your doctor may prescribe cholesterol-lowering medicines called statins to prevent future heart attacks.

Nitrates may be used to control remaining angina symptoms.

What to Think About

Do not substitute nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil, for example) or naproxen (such as Aleve), for aspirin. Although NSAIDS relieve pain and inflammation much like aspirin does, they may increase your risk for a heart attack or stroke.

If you had angioplasty and got a stent, you will take antiplatelet medicines to help prevent another heart attack or a stroke. You will probably take aspirin plus another antiplatelet such as clopidogrel (Plavix). If you get a drug-eluting stent, you will probably take both of these medicines for at least one year. If you get a bare metal stent, you will take both medicines for at least one month but maybe up to one year. Then, you will likely take daily aspirin long-term. If you have a high risk of bleeding, your doctor may shorten the time you take these medicines.

On rare occasions, coronary artery bypass graft surgery (CABG) is done on an emergency basis to treat a heart attack. Coronary artery bypass grafting, also called bypass surgery or "cabbage," may be needed when a heart attack cannot be safely and effectively treated with medicine or angioplasty. For example, bypass surgery may be done when there are blockages in the coronary arteries that cannot be reached during angioplasty or if angioplasty was tried but did not sufficiently widen the blood vessel.

Also, bypass surgery is often recommended in people with diabetes. Studies show that bypass surgery reduces the rate of death in people who have diabetes and heart attack when compared with angioplasty or thrombolytic therapy.²⁴

What to Think About

If muscles holding the heart valve in proper position were damaged by the heart attack, heart valve repair or replacement may be done at the same time as a coronary artery bypass.

After a heart attack, or after you have had angioplasty or bypass surgery, you may be encouraged to participate in a cardiac rehabilitation program to help lower your risk of death related to heart disease. For more information, see the topic Cardiac Rehabilitation.

In the past decade, angioplasty, also known as percutaneous coronary intervention (PCI), has become a common procedure in large medical centers in the United States. Angioplasty is done during cardiac catheterization or coronary angiogram.

During a cardiac catheterization, a tiny tube (called a catheter) is threaded through an artery of an arm or leg up into the heart and a dye that contains iodine is then injected through the catheter. The dye makes the coronary arteries visible on a digital X-ray screen. The doctor can then see on a TV screen whether your coronary arteries are blocked and how your heart is beating. If an artery appears blocked, angioplasty with or without stent placement may be done during the catheterization to open the blockage.

Studies show that angioplasty with stent placement, compared with angioplasty only, reduces the chance that the artery will renarrow and possibly reduces the risk of death.¹⁷ (See a picture of stent placement). Angioplasty with stent placement is less invasive and expensive than bypass surgery and is the preferred treatment for most people with a heart attack.

In some cases a heart attack causes enough muscle damage that your heart's pumping capacity is decreased. In this case, your doctor may recommend placement of a type of pacemaker called an implantable cardioverter-defibrillator (ICD), especially if you have life-threatening abnormal heart rhythms.

Living with a pacemaker or ICD.

What to Think About

Even with stents, an artery can renarrow after angioplasty, although recent innovations are improving the long-term success of this procedure. Drug-eluting stents are coated with medicines that prevent the artery from renarrowing. Experts do not know yet how safe the drug-eluting stents are over the long term or how well they work over the long term.

Although studies are not conclusive, folate therapy (taking a combination of folic acid, vitamin B6, and vitamin B12) may be harmful after stent placement and probably should be avoided.²⁵ Instead, try to get enough vitamin B by eating a balanced diet.

Although treatment for a heart attack is increasingly successful at prolonging life and reducing complications and hospitalization, a heart attack can lead to progressive, fatal conditions, such as heart failure and abnormal heart rhythms (arrhythmias). Many important end-of-life decisions can be made while you are active and able to communicate your wishes.

When you are diagnosed with a heart attack, your doctor will discuss treatment options with you. Your doctor may talk to you about your desire to be revived (resuscitated) if your heart stops pumping and you are unable to breathe on your own. You may want to learn more about aggressive life-sustaining medical treatment and whether it is right for you. For more information, see:

Should I receive CPR and mechanical ventilation?

Many other decisions about end-of-life issues, such as writing a living will and estate planning, can be made in advance, leaving valuable time that can be spent with loved ones and on other important matters. For more information, see the topics Care at the End of Life and Writing an Advance Directive.

Online Resource

Organizations

• Coronary Artery Disease
• Heart Failure
• High Blood Pressure (Hypertension)
• High Cholesterol

Citations

1. Gupta M, et al. (2002). Presenting complaint among patients with myocardial infarction who present to an urban, public hospital emergency department. Annals of Emergency Medicine, 40(2): 180–186.

2. Nissen SE, et al. (2005). Statin therapy, LDL cholesterol, C-reactive protein, and coronary artery disease. New England Journal of Medicine, 352(1): 29–38.

3. Ridker PM, et al. (2005). C-reactive protein levels and outcomes after statin therapy. New England Journal of Medicine, 352(1): 20–28.

4. Klocke FJ, et al. (2003). ACC/AHA/ASNC guidelines for the clinical use of cardiac radionuclide imaging—Executive Summary. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation, 108(11): 1404–1418. Available online: http://circ.ahajournals.org/content/vol108/issue11/index.shtml.

5. Grines CL, et al. (2003). Fibrinolytic therapy: Is it a treatment of the past? Circulation, 107(20): 2538–2542.

6. American College of Cardiology (ACC) and American Heart Association (AHA) (2002). Guideline update for the management of patients with unstable angina and non–ST-segment elevation myocardial infarction. Report of the ACC/AHA Task Force on Practice Guidelines. Available online: http://www.acc.org/clinical/topic/topic.htm#guidelines.

7. Grundy SM, et al. (2004). Implications of recent clinical trials of the National Cholesterol Education Program Adult Treatment Panel III Guidelines. Circulation, 110(2): 227–239. [Erratum in Circulation, 110(6): 763.]

8. Heart Protection Study Collaborative Group (2002). MRC/BHF Heart Protection Study of cholesterol lowering with simvastatin in 20,536 high-risk individuals: A randomised placebo-controlled trial. Lancet, 360(9326): 7–22.

9. Rea TD, et al. (2002). Smoking status and risk for recurrent coronary events after myocardial infarction. Annals of Internal Medicine, 137(6): 494–500.

10. Silagy C, et al. (2006). Nicotine replacement therapy for smoking cessation. Cochrane Database of Systematic Reviews (1). Oxford: Update Software.

11. American College of Cardiology and American Heart Association (2002). ACC/AHA/NASPE 2002 guideline update for implantation of cardiac pacemakers and antiarrhythmia devices. Summary article. Report of the ACC/AHA Task Force on Practice Guidelines. Available online: http://circ.ahajournals.org/cgi/content/full/106/16/2145

12. Topol EJ, Van De Werf FJ (2002). Acute myocardial infarction early diagnosis and management. In EJ Topol, ed., Textbook of Cardiovascular Medicine, 2nd ed., pp. 385–419. Philadelphia: Lippincott Williams and Wilkins.

13. Grundy S, et al. (2002). Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) (NIH Publication No. 02–5215). Bethesda, MD: National Institutes of Health. Also available online: http://www.nhlbi.nih.gov/guidelines/cholesterol/atp3full.pdf.

14. Heart Outcomes Prevention Evaluation (HOPE) 2 Investigators (2006). Homocysteine lowering with folic acid and B vitamins in vascular disease. New England Journal of Medicine, 354(15): 1567–1577.

15. Bonaa KH, et al. (2006). Homocysteine lowering and cardiovascular events after acute myocardial infarction. New England Journal of Medicine, 354(15): 1578–1588.

16. Rossouw JE, et al. (2007). Postmenopausal hormone therapy and risk of cardiovascular disease by age and years since menopause. JAMA, 297(13): 1465–1477.

17. Gami A (2006). Secondary prevention of ischaemic cardiac events, search date July 2004. Online version of Clinical Evidence (15): 1–31.

18. Selvin E, et al. (2004). Meta-analysis: Glycosylated hemoglobin and cardiovascular disease in diabetes mellitus. Annals of Internal Medicine, 141(6): 421–431.

19. American Diabetes Association (2006). Standards of medical care in diabetes. Clinical Practice Recommendations 2005. Diabetes Care, 29(Suppl 1): S3–S42.

20. De Lorgeril M, et al. (2002). Wine drinking and risks of cardiovascular complications after recent acute myocardial infarction. Circulation, 106(12): 1465–1469.

21. Mukamal KJ, et al. (2006). Alcohol consumption and risk for coronary heart disease in men with healthy lifestyles. Archives of Internal Medicine, 166(19): 2145–2150.

22. Goldberg IJ, et al. (2001). Wine and your heart: A science advisory for healthcare professionals from the Nutrition Committee, Council on Epidemiology and Prevention, and Council on Cardiovascular Nursing of the American Heart Association. Circulation, 103(3): 472–475.

23. Berkman LF, et al. (2003). Effects of treating depression and low perceived social support on clinical events after myocardial infarction: The Enhancing Recovery in Coronary Heart Disease Patients (ENRICHD) Randomized Trial. JAMA, 289(23): 3106–3116.

24. Aronson D, Rayfield EJ (2002). Diabetes. In EJ Topol, ed., Textbook of Cardiovascular Medicine, 2nd ed., pp. 139–170. Philadelphia: Lippincott Williams and Wilkins.

25. Lange H, et al. (2004). Folate therapy and in-stent restenosis after coronary stenting. New England Journal of Medicine, 350(26): 2673–2681.

Other Works Consulted

• Joint European Society of Cardiology and the American College of Cardiology Committee (2000). Myocardial infarction redefined: A consensus document. Journal of the American College of Cardiology, 36(3): 959–969.

• American Heart Association and American College of Cardiology (2006). AHA/ACC Guidelines for secondary prevention for patients with coronary and other atherosclerotic vascular disease: 2006 update. Circulation, 113(19): 2363–2372. [Erratum in Circulation, 113(22): 847.]

• Antman EM, et al. (2007). 2007 focused update of the ACC/AHA 2004 guidelines for the management of patients with ST-elevation myocardial infarction: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation, 117(2): 296–329. Originally published online December 10, 2007 (doi:10.1161/circulationaha.107.188209).

• King SB III, et al. (2007). 2007 focused update of the ACC/AHA/SCAI 2005 guideline update for percutaneous coronary intervention: A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation, 117(2): 261–295. Originally published online December 13, 2007 (doi:10.1161/circulationaha.107.188208).

• Kloner RA, et al. (2003). Cardiovascular Trials Review, 8th ed. Darien, CT: Le Jacq Communications.