What is a heart attack?

A heart attack happens when the flow of oxygen-rich blood to a section of heart muscle suddenly becomes blocked and the heart can’t get oxygen. If blood flow isn’t restored quickly, the section of heart muscle begins to die ¹. Every 40 seconds, someone in the United States has a heart attack ².

Heart attack treatment works best when it’s given right after symptoms occur.

• Don’t Wait–Get Help Quickly
• Quick Action Can Save Your Life
• If you think you or someone else is having a heart attack, even if you’re not sure, don’t feel embarrassed to call your local emergency number right away !
• Do not drive to the hospital or let someone else drive you. Call an ambulance so that medical personnel can begin life-saving treatment on the way to the emergency room. Take a nitroglycerin pill if your doctor has prescribed this type of treatment.

Other Names for a Heart Attack

• Myocardial infarction (MI)
• Acute myocardial infarction (AMI)
• Acute coronary syndrome
• Coronary thrombosis
• Coronary occlusion

Every year, about 790,000 Americans have a heart attack. Of these cases

• 580,000 are a first heart attack.
• 210,000 happen to people who have already had a first heart attack ².
• About 15% of people who have a heart attack will die from it ².
• Almost half of sudden cardiac deaths happen outside a hospital ³.
• One of 5 heart attacks is silent—the damage is done, but the person is not aware of it ².

Heart attacks most often occur as a result of coronary heart disease (CHD), also called coronary artery disease. Coronary heart disease is a condition in which a waxy substance called plaque (cholesterol plaque) builds up inside the coronary arteries. These arteries supply oxygen-rich blood to your heart.

When plaque builds up in the arteries, the condition is called atherosclerosis. The buildup of plaque occurs over many years.

Eventually, an area of plaque can rupture (break open) inside of an artery. This causes a blood clot to form on the plaque’s surface. If the clot becomes large enough, it can mostly or completely block blood flow through a coronary artery.

If the blockage isn’t treated quickly, the portion of heart muscle fed by the artery begins to die. Healthy heart tissue is replaced with scar tissue. This heart damage may not be obvious, or it may cause severe or long-lasting problems.

Figure 1. Heart With Muscle Damage and a Blocked Artery

[Source ¹]

A less common cause of heart attack is a severe spasm (tightening) of a coronary artery. The spasm cuts off blood flow through the artery. Spasms can occur in coronary arteries that aren’t affected by atherosclerosis.

Heart attacks can be associated with or lead to severe health problems, such as heart failure and life-threatening arrhythmias.

Heart failure is a condition in which the heart can’t pump enough blood to meet the body’s needs. Arrhythmias are irregular heartbeats. Ventricular fibrillation is a life-threatening arrhythmia that can cause death if not treated right away.

Causes of heart attack

Coronary Heart Disease

A heart attack happens if the flow of oxygen-rich blood to a section of heart muscle suddenly becomes blocked and the heart can’t get oxygen. Most heart attacks occur as a result of coronary heart disease (CHD) ⁴.

Coronary heart disease is a condition in which a waxy substance called plaque builds up inside of the coronary arteries. These arteries supply oxygen-rich blood to your heart.

When plaque builds up in the arteries, the condition is called atherosclerosis. The buildup of plaque occurs over many years.

Eventually, an area of plaque can rupture (break open) inside of an artery. This causes a blood clot to form on the plaque’s surface. If the clot becomes large enough, it can mostly or completely block blood flow through a coronary artery.

If the blockage isn’t treated quickly, the portion of heart muscle fed by the artery begins to die. Healthy heart tissue is replaced with scar tissue. This heart damage may not be obvious, or it may cause severe or long-lasting problems.

Coronary Artery Spasm

A less common cause of heart attack is a severe spasm (tightening) of a coronary artery ⁴. The spasm cuts off blood flow through the artery. Spasms can occur in coronary arteries that aren’t affected by atherosclerosis.

What causes a coronary artery to spasm isn’t always clear. A spasm may be related to:

• Taking certain drugs, such as cocaine
• Emotional stress or pain
• Exposure to extreme cold
• Cigarette smoking.

Who is at Risk for a Heart Attack ?

Certain risk factors make it more likely that you’ll develop coronary heart disease and have a heart attack ⁵. You can control many of these risk factors.

Risk Factors You Can Control

The major risk factors for a heart attack that you can control include:

• Smoking
• High blood pressure
• High blood cholesterol
• Overweight and obesity
• An unhealthy diet (for example, a diet high in saturated fat, trans fat, cholesterol, and sodium)
• Lack of routine physical activity
• High blood sugar due to insulin resistance or diabetes.

Some of these risk factors—such as obesity, high blood pressure, and high blood sugar—tend to occur together. When they do, it’s called metabolic syndrome.

In general, a person who has metabolic syndrome is twice as likely to develop heart disease and five times as likely to develop diabetes as someone who doesn’t have metabolic syndrome.

For more information about the risk factors that are part of metabolic syndrome, go to the The Metabolic Syndrome article.

Risk Factors You Can’t Control

Risk factors that you can’t control include:

• Age. The risk of heart disease increases for men after age 45 and for women after age 55 (or after menopause).
• Family history of early heart disease. Your risk increases if your father or a brother was diagnosed with heart disease before 55 years of age, or if your mother or a sister was diagnosed with heart disease before 65 years of age.
• Preeclampsia. This condition can develop during pregnancy. The two main signs of preeclampsia are a rise in blood pressure and excess protein in the urine. Preeclampsia is linked to an increased lifetime risk of heart disease, including coronary heart disease, heart attack, heart failure, and high blood pressure.

Symptoms of a heart attack

Remember acting fast at the first sign of heart attack symptoms can save your life and limit damage to your heart ¹. Treatment works best when it’s given right after symptoms occur.

Not all heart attacks begin with the sudden, crushing chest pain that often is shown on TV or in the movies. In one study, for example, one-third of the patients who had heart attacks had no chest pain ⁶. These patients were more likely to be older, female, or diabetic.

The symptoms of a heart attack can vary from person to person. Some people can have few symptoms and are surprised to learn they’ve had a heart attack. If you’ve already had a heart attack, your symptoms may not be the same for another one. It is important for you to know the most common symptoms of a heart attack and also remember these facts:

• Heart attacks can start slowly and cause only mild pain or discomfort. Symptoms can be mild or more intense and sudden. Symptoms also may come and go over several hours.
• People who have high blood sugar (diabetes) may have no symptoms or very mild ones.
• The most common symptom, in both men and women, is chest pain or discomfort.
• Women are somewhat more likely to have shortness of breath, nausea and vomiting, unusual tiredness (sometimes for days), and pain in the back, shoulders, and jaw.

Some people don’t have symptoms at all. Heart attacks that occur without any symptoms or with very mild symptoms are called silent heart attacks.

Many people aren’t sure what’s wrong when they are having symptoms of a heart attack.

Most Common Symptoms

The most common warning symptoms of a heart attack for both men and women are:

• Chest pain or discomfort. Most heart attacks involve discomfort in the center or left side of the chest. The discomfort usually lasts for more than a few minutes or goes away and comes back. It can feel like pressure, squeezing, fullness, or pain. It also can feel like heartburn or indigestion. The feeling can be mild or severe.
• Upper body discomfort. You may feel pain or discomfort in one or both arms, the back, shoulders, neck, jaw, or upper part of the stomach (above the belly button).
• Shortness of breath. This may be your only symptom, or it may occur before or along with chest pain or discomfort. It can occur when you are resting or doing a little bit of physical activity.

Not everyone having a heart attack has typical symptoms. If you’ve already had a heart attack, your symptoms may not be the same for another one. However, some people may have a pattern of symptoms that recur.

The more signs and symptoms you have, the more likely it is that you’re having a heart attack.

Other Common Signs and Symptoms include:

• Breaking out in a cold sweat
• Feeling unusually tired for no reason, sometimes for days (especially if you are a woman)
• Nausea (feeling sick to the stomach) and vomiting
• Light-headedness or sudden dizziness
• Any sudden, new symptom or a change in the pattern of symptoms you already have (for example, if your symptoms become stronger or last longer than usual)

The symptoms of angina can be similar to the symptoms of a heart attack. Angina is chest pain that occurs in people who have coronary heart disease, usually when they’re active. Angina pain usually lasts for only a few minutes and goes away with rest.

Chest pain or discomfort that doesn’t go away or changes from its usual pattern (for example, occurs more often or while you’re resting) can be a sign of a heart attack.

• All chest pain should be checked by a doctor.

The signs and symptoms of a heart attack can develop suddenly. However, they also can develop slowly—sometimes within hours, days, or weeks of a heart attack.

Any time you think you might be having heart attack symptoms or a heart attack, don’t ignore it or feel embarrassed to call for help. Call your local emergency number for emergency medical care, even if you are not sure whether you’re having a heart attack. Here’s why:

• Acting fast can save your life.
• An ambulance is the best and safest way to get to the hospital. Emergency medical services personnel can check how you are doing and start life-saving medicines and other treatments right away. People who arrive by ambulance often receive faster treatment at the hospital.
• The emergency phone operator or EMS technician can give you advice. You might be told to crush or chew an aspirin if you’re not allergic, unless there is a medical reason for you not to take one. Aspirin taken during a heart attack can limit the damage to your heart and save your life.

Every minute matters. Never delay calling your local emergency number in order to take aspirin or do anything else you think might help.

How is a Heart Attack Diagnosed ?

Your doctor will diagnose a heart attack based on your signs and symptoms, your medical and family histories, and test results ⁷.

Diagnostic Tests

• EKG (Electrocardiogram)

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 each part of the heart.

An EKG can show signs of heart damage due to coronary heart disease and signs of a previous or current heart attack.

• Blood Tests

During a heart attack, heart muscle cells die and release proteins into the bloodstream. Blood tests can measure the amount of these proteins in the bloodstream. Higher than normal levels of these proteins suggest a heart attack.

Commonly used blood tests include troponin tests, CK or CK–MB tests, and serum myoglobin tests. Blood tests often are repeated to check for changes over time.

• Coronary Angiography

Coronary angiography is a test that uses dye and special x-rays to show the insides of your coronary arteries. This test often is done during a heart attack to help find blockages in the coronary arteries.

To get the dye into your coronary arteries, your doctor will use a procedure called cardiac catheterization. A thin, flexible tube called a catheter is put into a blood vessel in your arm, groin (upper thigh), or neck. The tube is threaded into your coronary arteries, and the dye is released into your bloodstream. Special x-rays are taken while the dye is flowing through the coronary arteries. The dye lets your doctor study the flow of blood through the heart and blood vessels.

If your doctor finds a blockage, he or she may recommend a procedure called percutaneous coronary intervention, sometimes referred to as coronary angioplasty. This procedure can help restore blood flow through a blocked artery. Sometimes a small mesh tube called a stent is placed in the artery to help prevent blockages after the procedure.

Treatment of a heart attack

Early treatment for a heart attack can pr event or limit damage to the heart muscle ⁸. Acting fast, by calling your local emergency number at the first symptoms of a heart attack, can save your life. Medical personnel can begin diagnosis and treatment even before you get to the hospital.

Immediate Treatment

Certain treatments usually are started right away if a heart attack is suspected, even before the diagnosis is confirmed. These include:

• Aspirin to prevent further blood clotting
• Nitroglycerin to reduce your heart’s workload and improve blood flow through the coronary arteries
• Oxygen therapy
• Treatment for chest pain

Once the diagnosis of a heart attack is confirmed or strongly suspected, doctors start treatments promptly to try to restore blood flow through the blood vessels supplying the heart. The two main treatments are clot-busting medicines and percutaneous coronary intervention, also known as coronary angioplasty, a procedure used to open blocked coronary arteries.

Clot-Busting Medicines

Thrombolytic medicines, also called clot busters, are used to dissolve blood clots that are blocking the coronary arteries. To work best, these medicines must be given within several hours of the start of heart attack symptoms. Ideally, the medicine should be given as soon as possible.

Percutaneous Coronary Intervention

Percutaneous coronary intervention is a nonsurgical procedure that opens blocked or narrowed coronary arteries. A thin, flexible tube (catheter) with a balloon or other device on the end is threaded through a blood vessel, usually in the groin (upper thigh), to the narrowed or blocked coronary artery. Once in place, the balloon located at the tip of the catheter is inflated to compress the plaque and related clot against the wall of the artery. This restores blood flow through the artery. During the procedure, the doctor may put a small mesh tube called a stent in the artery. The stent helps to keep the blood vessel open to prevent blockages in the artery in the months or years after the procedure.

Other Treatments for Heart Attack

Other treatments for heart attack include:

• Medicines
• Medical procedures
• Heart-healthy lifestyle changes
• Cardiac rehabilitation

Medicines

Your doctor may prescribe one or more of the following medicines.

• ACE inhibitors. ACE inhibitors lower blood pressure and reduce strain on your heart. They also help slow down further weakening of the heart muscle.
• Anticlotting medicines. Anticlotting medicines stop platelets from clumping together and forming unwanted blood clots. Examples of anticlotting medicines include aspirin and clopidogrel.
• Anticoagulants. Anticoagulants, or blood thinners, prevent blood clots from forming in your arteries. These medicines also keep existing clots from getting larger.
• Beta blockers. Beta blockers decrease your heart’s workload. These medicines also are used to relieve chest pain and discomfort and to help prevent another heart attack. Beta blockers also are used to treat arrhythmias (irregular heartbeats).
• Statin medicines. Statins control or lower your blood cholesterol. By lowering your blood cholesterol level, you can decrease your chance of having another heart attack or stroke.

You also may be given medicines to relieve pain and anxiety, and treat arrhythmias. Take all medicines regularly, as your doctor prescribes. Don’t change the amount of your medicine or skip a dose unless your doctor tells you to.

Medical Procedures

Coronary artery bypass grafting also may be used to treat a heart attack. During coronary artery bypass grafting, a surgeon removes a healthy artery or vein from your body. The artery or vein is then connected, or grafted, to bypass the blocked section of the coronary artery. The grafted artery or vein bypasses (that is, goes around) the blocked portion of the coronary artery. This provides a new route for blood to flow to the heart muscle.

Heart-Healthy Lifestyle Changes

Treatment for a heart attack usually includes making heart-healthy lifestyle changes. Your doctor also may recommend:

• Heart-healthy eating
• Aiming for healthy weight
• Managing stress
• Physical activity
• Quitting smoking

Taking these steps can lower your chances of having another heart attack.

Cardiac Rehabilitation

Your doctor may recommend cardiac rehabilitation (cardiac rehab) to help you recover from a heart attack and to help prevent another heart attack. Nearly everyone who has had a heart attack can benefit from rehab. Cardiac rehab is a medically supervised program that may help improve the health and well-being of people who have heart problems.

The cardiac rehab team may include doctors, nurses, exercise specialists, physical and occupational therapists, dietitians or nutritionists, and psychologists or other mental health specialists.

Rehab has two parts:

1. Education, counseling, and training. This part of rehab helps you understand your heart condition and find ways to reduce your risk for future heart problems. The rehab team will help you learn how to cope with the stress of adjusting to a new lifestyle and how to deal with your fears about the future.
2. Exercise training. This part helps you learn how to exercise safely, strengthen your muscles, and improve your stamina. Your exercise plan will be based on your personal abilities, needs, and interests.

How to prevent getting a heart attack

When heart experts talk about prevention, they usually refer to one of three types: secondary, primary and primordial prevention ⁹. All three have similar elements, but different starting times and different effects.

Primordial prevention

The word “primordial” means existing from the beginning. Primordial prevention involves working to prevent inflammation, atherosclerosis, and endothelial dysfunction from taking hold, and thus prevent risk factors such as high blood pressure, high cholesterol, excess weight, and ultimately cardiovascular events. Once rarely discussed, primordial prevention is now the cornerstone of the American Heart Association’s definition of ideal heart health and efforts to help people achieve it ⁹. As its name implies, the sooner you can start practicing primordial prevention—ideally from childhood on—the more likely you are to achieve it and protect yourself from heart disease.

Primary prevention

Primary prevention aims to keep an individual at risk of heart disease from having a first heart attack or stroke, needing angioplasty or surgery, or developing some other form of heart disease ⁹. Primary prevention is usually aimed at people who already have developed cardiovascular risk factors, such as high blood pressure or high cholesterol. As with secondary prevention, primary prevention focuses on controlling these risk factors by making healthy lifestyle changes and, if needed, taking medications. That said, the appearance of worrisome cardiovascular risk factors means that inflammation, atherosclerosis, and/or endothelial dysfunction are already at work and, in most cases, aren’t reversible.

Secondary prevention

These efforts are started after someone has a heart attack or stroke, undergoes angioplasty or bypass surgery, or develops some other form of heart disease ⁹. It involves taking medications like aspirin and/or a cholesterol-lowering statin, quitting smoking and losing weight if needed, exercising more, and following a healthy diet. Although secondary prevention may sound like “closing the barn door after the horse has gone,” it isn’t. These steps can prevent a second heart attack or stroke, halt the progression of heart disease, and prevent early death. It may be obvious, but the number one killer of individuals who survive a first heart attack is a second heart attack.

Steps for the prevention of heart disease (before you have a heart attack)

Four key choices can dramatically reduce your chances of developing cardiovascular risk factors and ultimately heart disease. All four are important. Below, each choice is listed in order of significance to heart health, along with ways to put each into practice.

1. Not smoking

One of the best things you can do for your health is to not use tobacco in any form. Tobacco use is a hard-to-break habit that can slow you down, make you sick, and shorten your life. One way it does this is by contributing to heart disease.

In fact, researchers examining the relationship between cigarette smoking and smoking cessation on mortality during a decades-long perspective study of over 100,000 women found that approximately 64% of deaths among current smokers and 28% of deaths among former smokers were attributable to cigarette smoking ¹⁰.

This study ¹⁰ also reported that much of the excess risk due to smoking may be drastically lowered after quitting. Additionally, the excess risk for all-cause mortality—that is, death from any cause—decreases to the level of a “never-smoker” 20 years after quitting.

The nicotine that tobacco products deliver is one of the most addictive substances around. That makes tobacco use one of the toughest unhealthy habits to break. But don’t get discouraged; many smokers do quit! In fact, in the United States today there are more ex-smokers than smokers ¹¹. Learn more about the hazards of smoking, the benefits of quitting, and tips for quitting from the Centers for Disease Control and Prevention ¹².

2. Maintaining a healthy weight

Excess weight and an extra-large waist size both contribute to heart disease, as well as a host of other health problems ¹³, ¹⁴, ¹⁵.

In a study of over one million women, body-mass index (BMI) was a strong risk factor for coronary heart disease. The incidence of coronary heart disease increases progressively with BMI ¹⁶.

In the Nurses’ Health Study and the Health Professionals Follow-Up Study, middle-aged women and men who gained 11 to 22 pounds after age 20 were up to three times more likely to develop heart disease, high blood pressure, type 2 diabetes, and gallstones than those who gained five pounds or fewer.

Those who gained more than 22 pounds had an even greater risk of developing these diseases ¹³, ¹⁷, ¹⁸.

Weight and height go hand-in-hand. The taller you are, the more you weigh. That’s why researchers have devised several measures that account for both weight and height. The one most commonly used is BMI.

You can calculate your BMI by dividing your weight in kilograms by your height in meters squared (kg/m2). You can also use an online BMI calculator or BMI table.

To find out about your body mass index (BMI), you can use a FREE online BMI calculators from the Centers for Disease Control and Prevention (CDC) :

• Adults ¹⁹

For children and adolescents (younger than 20 years of age), overweight and obesity are based on the Centers for Disease Control and Prevention’s (CDC’s) BMI-for-age growth charts, which are available at ²⁰.

The CDC has a BMI percentile calculator for children and teens at ²¹.

• Children ²²

Body Mass Index for Men and Women Adults

The body mass index is an attempt to quantify the amount of tissue mass (muscle, fat, and bone) in an individual, and then categorize that person as underweight, normal weight, overweight, or obese based on that value. Commonly accepted body mass index ranges are:

A) Underweight: under 18.5 kg/m²,

B) Normal (Healthy BMI) weight: 18.5 to 25 kg/m²,

C) Overweight: 25 to 30 kg/m²,

D) Obese: over 30 to 39.9 kg/m².

E) Severely Obese: over 40 kg/m².

Waist size matters, too. In people who are not overweight, waist size may be an even more telling warning sign of increased health risks than BMI ²³. An expert panel convened by the National Institutes of Health identified these useful benchmarks: Men should aim for a waist size below 40 inches (102 cm) and women should aim for a waist size below 35 inches (88 cm) ²⁴.

3. Exercising

Exercise and physical activity are excellent ways to prevent heart disease and many other diseases and conditions ²⁵, ²⁶, ²⁷, but many of us get less activity as we get older.

Getting regular physical activity is one of the best things you can do for your health. It lowers the risk of heart disease, diabetes, stroke, high blood pressure, osteoporosis, and certain cancers, and it can also help control stress, improve sleep, boost mood, keep weight in check, and reduce the risk of falling and improve cognitive function in older adults.

It doesn’t take marathon training to see real health gains. A 30-minute brisk walk five days of the week will provide important benefits for most people. Getting any amount of exercise is better than none.

Exercise and physical activity benefit the body, while a sedentary lifestyle does the opposite—increasing the chances of becoming overweight and developing a number of chronic diseases.

Research shows that people who spend more time each day watching television, sitting, or riding in cars have a greater chance of dying early than people who are more active ²⁸, ²⁹, ³⁰. A 2013 study showed that, among women ages 50-79 with no cardiovascular disease at the start of study, prolonged sitting time was associated with increased heart disease risk regardless of the amount of time spent in leisure-time physical activity ²⁷.

4. Following a healthy diet

For years, research into connections between diet and heart disease focused on individual nutrients like cholesterol (and foods high in dietary cholesterol, like eggs), types of fats, and specific vitamins and minerals. This work has been revealing, but it has also generated some dead ends, along with myths and confusion about what constitutes a heart-healthy diet. That’s because people eat food, not nutrients.

• The best diet for preventing heart disease is one that is full of fruits and vegetables, whole grains, nuts, fish, poultry, and vegetable oils; includes alcohol in moderation, if at all; and goes easy on red and processed meats, refined carbohydrates, foods and beverages with added sugar, sodium, and foods with trans fat.
• People with diets consistent with this dietary pattern had a 31% lower risk of heart disease, a 33% lower risk of diabetes, and a 20% lower risk of stroke ³¹.
• A randomized controlled trial found that a Mediterranean diet supplemented with extra-virgin olive oil or nuts, both rich sources of unsaturated fat, reduced the incidence of major cardiovascular events amongst patients with cardiovascular disease over a 4.8-year follow-up period. This study highlighted that low-fat diets are not beneficial to heart health, and that incorporating healthy fats – such as those included in the
• Mediterranean diet – can improve heart health and weight loss.
  There isn’t one exact Mediterranean diet, as this eating style takes into account the different foods, eating patterns, and lifestyles in multiple countries that border the Mediterranean Sea. However, there are similarities that define a Mediterranean eating pattern, and as described by this study the traditional

Mediterranean diet includes:

• High intake of olive oil, nuts, vegetables, fruits, and cereals
• Moderate intake of fish and poultry
• Low intake of dairy products, red meat, processed meats, and sweets
• Wine in moderation, consumed with meals ³².

Prevention of Heart Attack Summary

You can help prevent heart disease by doing four key things and making them into habits:

• Don’t smoke (or quit if you do)
• Maintain a healthy weight
• Exercise; be active
• Follow a healthy diet

Table 1. Lifestyle factors for heart attack prevention

Goal/Metric	Ideal Cardiovascular Health Definition
*The committee selected 5 aspects of diet to define a healthy dietary score. The score is not intended to be comprehensive. Rather, it is a practical approach that provides individuals with a set of potential concrete actions. A comprehensive rationale is set forth in the text of this document, and a comprehensive set of nutrition recommendations is provided in the 2006 Nutrition Guidelines 33, 34, 35.
†Untreated values.
Current smoking
Adults >20 y of age	Never or quit >12 mo ago
Children 12–19 y of age	Never tried; never smoked whole cigarette
Body mass index
Adults >20 y of age	<25 kg/m2
Children 2–19 y of age	<85th Percentile
Physical activity
Adults >20 y of age	≥150 min/wk moderate intensity or ≥75 min/wk vigorous intensity or combination
Children 12–19 y of age	≥60 min of moderate- or vigorous-intensity activity every day
Healthy diet score*
Adults >20 y of age	4–5 Components*
Children 5–19 y of age	4–5 Components*
Total cholesterol
Adults >20 y of age	<200 mg/dL†
Children 6–19 y of age	<170 mg/dL†
Blood pressure
Adults >20 y of age	<120/<80 mm Hg†
Children 8–19 y of age	<90th Percentile†
Fasting plasma glucose
Adults >20 y of age	<100 mg/dL†
Children 12–19 y of age	<100 mg/dL†

[Source ⁹]

Strong studies make it possible to link reductions in risk to these habits. Following a healthy lifestyle may prevent over 80% of cases of coronary artery disease ³⁶, ³⁷, 50% of ischemic strokes ³⁸, 80% of sudden cardiac deaths ³⁹ and 72% of premature deaths related to heart disease ⁴⁰. In other words, a healthy lifestyle is a good investment in a longer, healthier life.

Steps for the primary and secondary prevention of a heart attack

Lowering your risk factors for coronary heart disease can help you prevent a heart attack. Even if you already have coronary heart disease, you still can take steps to lower your risk for a heart attack. These steps involve making heart-healthy lifestyle changes and getting ongoing medical care for related conditions that make heart attack more likely. Talk to your doctor about whether you may benefit from aspirin primary prevention, or using aspirin to help prevent your first heart attack.

Heart-Healthy Lifestyle Changes

A heart-healthy lifestyle can help prevent a heart attack and includes heart-healthy eating, being physically active, quitting smoking, managing stress, and managing your weight.

Ongoing Care – Treat Related Conditions

Treating conditions that make a heart attack more likely also can help lower your risk for a heart attack. These conditions may include:

• Diabetes (high blood sugar). If you have diabetes, try to control your blood sugar level through diet and physical activity (as your doctor recommends). If needed, take medicine as prescribed.
• High blood cholesterol. Your doctor may prescribe a statin medicine to lower your cholesterol if diet and exercise aren’t enough.
• High blood pressure. Your doctor may prescribe medicine to keep your blood pressure under control.
• Chronic kidney disease. Your doctor may prescribe medicines to control your high blood pressure or high blood sugar levels.
• Peripheral artery disease. Your doctor may recommend surgery or procedures to unblock the affected arteries.

Have an Emergency Action Plan

Make sure that you have an emergency action plan in case you or someone in your family has a heart attack. This is very important if you’re at high risk for, or have already had, a heart attack.

Write down a list of medicines you are taking, medicines you are allergic to, your health care provider’s phone numbers (both during and after office hours), and contact information for a friend or relative. Keep the list in a handy place (for example, fill out this wallet card) to share in a medical emergency.

Talk with your doctor about the signs and symptoms of a heart attack, when you should call your local emergency number, and steps you can take while waiting for medical help to arrive.

Life After a Heart Attack

Many people survive heart attacks and live active, full lives ⁴¹. If you get help quickly, treatment can limit damage to your heart muscle. Less heart damage improves your chances for a better quality of life after a heart attack.

Medical Followup

After a heart attack, you’ll need treatment for coronary heart disease. This will help prevent another heart attack. Your doctor may recommend:

• Lifestyle changes, such as following a healthy diet, being physically active, maintaining a healthy weight, and quitting smoking.
• Medicines to control chest pain or discomfort, high blood cholesterol, high blood pressure, and your heart’s workload. Some of these medicines can help you prevent another heart attack.
• Anticlotting medicines, such as aspirin, that your doctor may prescribe to help you prevent another heart attack.
• A cardiac rehabilitation program

If you find it hard to get your medicines or or complete your cardiac rehabilitation program, talk with your doctor. Don’t stop the medicines or program because it can help you prevent another heart attack.

Returning to Normal Activities

After a heart attack, most people who don’t have chest pain or discomfort or other problems can safely return to most of their normal activities within a few weeks. Most can begin walking right away.

Sexual activity also can begin within a few weeks for most patients. Talk with your doctor about a safe schedule for returning to your normal routine.

If allowed by State law, driving usually can begin within a week for most patients who don’t have chest pain or discomfort or other disabling problems. Each State has rules about driving a motor vehicle following a serious illness. People who have complications shouldn’t drive until their symptoms have been stable for a few weeks.

Anxiety and Depression After a Heart Attack

After a heart attack, many people worry about having another heart attack. Sometimes they feel depressed and have trouble adjusting to new lifestyle changes.

Talk about how you feel with your health care team. 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.

Joining a patient support group may help you adjust to life after a heart attack. You can see how other people who have the same symptoms have coped with them. Talk with your doctor about local support groups or check with an area medical center.

Support from family and friends also can help relieve stress and anxiety. Let your loved ones know how you feel and what they can do to help you.

Risk of a Repeat Heart Attack

Once you’ve had a heart attack, you’re at higher risk for another one ⁴¹. Knowing the difference between angina and a heart attack is important. Angina is chest pain that occurs in people who have coronary heart disease.

The pain from angina usually occurs after physical exertion and goes away in a few minutes when you rest or take medicine as directed.

The pain from a heart attack usually is more severe than the pain from angina. Heart attack pain doesn’t go away when you rest or take medicine.

If you don’t know whether your chest pain is angina or a heart attack, call your local emergency number.

The symptoms of a second heart attack may not be the same as those of a first heart attack. Don’t take a chance if you’re in doubt. Always call your local emergency number right away if you or someone else has heart attack symptoms.

Unfortunately, most heart attack victims wait 2 hours or more after their symptoms start before they seek medical help. This delay can result in lasting heart damage or death ⁴¹.

What is coronary heart disease ?

Coronary heart disease (CHD) is a disease in which a waxy substance called plaque builds up inside the coronary arteries. Arteries are blood vessels that carry oxygen-rich blood to your heart and other parts of your body. These arteries supply oxygen-rich blood to your heart muscle. 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.

When plaque builds up in the arteries, the condition is called atherosclerosis.

Atherosclerosis is a disease in which plaque builds up inside your arteries. The buildup of plaque occurs over many years.

Atherosclerosis plaque narrows the coronary arteries and reduces blood flow to your heart muscle. Plaque narrows and stiffens the coronary arteries. This reduces the flow of oxygen-rich blood to the heart muscle, causing chest pain.

Plaque buildup also makes it more likely that blood clots will form in your arteries. Blood clots can partially or completely block blood flow, which can cause a heart attack.

• 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 coronary heart disease.

Atherosclerosis can lead to serious problems, including heart attack, stroke, or even death.

Figure 2. Atherosclerosis plaque

[Source ⁴²]

Figure 3. Atherosclerosis blocking the artery supply in your heart

[Source ⁴²]

What is Angina ?

Angina is chest pain or discomfort that occurs if an area of your heart muscle doesn’t get enough oxygen-rich blood.

Angina isn’t a disease; it’s a symptom of an underlying heart problem ⁴³. Angina usually is a symptom of coronary heart disease (CHD).

Angina may feel like pressure or squeezing in your chest. The pain also can occur in your shoulders, arms, neck, jaw, or back. Angina pain may even feel like indigestion.

Coronary heart disease is the most common type of heart disease in adults. It occurs if a waxy substance called plaque builds up on the inner walls of your coronary arteries. These arteries carry oxygen-rich blood to your heart.

Angina also can be a symptom of coronary microvascular disease (MVD). This is heart disease that affects the heart’s smallest coronary arteries. In coronary microvascular disease, plaque doesn’t create blockages in the arteries like it does in coronary heart disease.

Studies have shown that coronary microvascular disease is more likely to affect women than men. Coronary microvascular disease also is called cardiac syndrome X and nonobstructive coronary heart disease.

Overview

Experts believe that nearly 7 million people in the United States suffer from angina ⁴³. The condition occurs equally among men and women.

Angina can be a sign of coronary heart disease, even if initial tests don’t point to the disease. However, not all chest pain or discomfort is a sign of coronary heart disease.

Other conditions also can cause chest pain, such as:

• Pulmonary embolism (a blockage in a lung artery)
• A lung infection
• Aortic dissection (tearing of a major artery)
• Aortic stenosis (narrowing of the heart’s aortic valve)
• Hypertrophic cardiomyopathy (heart muscle disease)
• Pericarditis (inflammation in the tissues that surround the heart)
• A panic attack

All chest pain should be checked by a doctor.

Types of Angina

The major types of angina are stable, unstable, variant (Prinzmetal’s), and microvascular ⁴³. Knowing how the types differ is important. This is because they have different symptoms and require different treatments.

Stable Angina

Stable angina is the most common type of angina. It occurs when the heart is working harder than usual. Stable angina has a regular pattern. (“Pattern” refers to how often the angina occurs, how severe it is, and what factors trigger it.)

If you have stable angina, you can learn its pattern and predict when the pain will occur. The pain usually goes away a few minutes after you rest or take your angina medicine.

Stable angina isn’t a heart attack, but it suggests that a heart attack is more likely to happen in the future.

Unstable Angina

Unstable angina doesn’t follow a pattern. It may occur more often and be more severe than stable angina. Unstable angina also can occur with or without physical exertion, and rest or medicine may not relieve the pain.

Unstable angina is very dangerous and requires emergency treatment. This type of angina is a sign that a heart attack may happen soon.

Variant (Prinzmetal’s) Angina

Variant angina is rare. A spasm in a coronary artery causes this type of angina ⁴³. Variant angina usually occurs while you’re at rest, and the pain can be severe. It usually happens between midnight and early morning. Medicine can relieve this type of angina.

Microvascular Angina

Microvascular angina can be more severe and last longer than other types of angina ⁴³. Medicine may not relieve this type of angina.

Other names for Angina

• Acute coronary syndrome
• Angina pectoris
• Chest pain
• Coronary artery spasms
• Microvascular angina
• Prinzmetal’s angina
• Stable or common angina
• Unstable angina
• Variant angina.

Who is at Risk for Angina ?

Angina is a symptom of an underlying heart problem. It’s usually a symptom of coronary heart disease, but it also can be a symptom of coronary microvascular disease. So, if you’re at risk for coronary heart disease or coronary microvascular disease, you’re also at risk for angina ⁴⁴.

The major risk factors for coronary heart disease and coronary microvascular disease include:

• Unhealthy cholesterol levels.
• High blood pressure.
• Smoking.
• Insulin resistance or diabetes.
• Overweight or obesity.
• Metabolic syndrome.
• Lack of physical activity.
• Unhealthy diet.
• Older age. (The risk increases for men after 45 years of age and for women after 55 years of age.)
• Family history of early heart disease.

People sometimes think that because men have more heart attacks than women, men also suffer from angina more often. In fact, overall, angina occurs equally among men and women ⁴⁴.

Microvascular angina, however, occurs more often in women. About 70 percent of the cases of microvascular angina occur in women around the time of menopause ⁴⁴.

Unstable angina occurs more often in older adults ⁴⁴. Variant angina is rare; it accounts for only about 2 out of 100 cases of angina. People who have variant angina often are younger than those who have other forms of angina ⁴⁴.

What are the Signs and Symptoms of Angina ?

Pain and discomfort are the main symptoms of angina. Angina often is described as pressure, squeezing, burning, or tightness in the chest. The pain or discomfort usually starts behind the breastbone ⁴⁵.

Pain from angina also can occur in the arms, shoulders, neck, jaw, throat, or back. The pain may feel like indigestion. Some people say that angina pain is hard to describe or that they can’t tell exactly where the pain is coming from.

Signs and symptoms such as nausea (feeling sick to your stomach), fatigue (tiredness), shortness of breath, sweating, light-headedness, and weakness also may occur.

Women are more likely to feel discomfort in the neck, jaw, throat, abdomen, or back. Shortness of breath is more common in older people and those who have diabetes. Weakness, dizziness, and confusion can mask the signs and symptoms of angina in elderly people.

Symptoms also vary based on the type of angina you have.

Because angina has so many possible symptoms and causes, all chest pain should be checked by a doctor. Chest pain that lasts longer than a few minutes and isn’t relieved by rest or angina medicine may be a sign of a heart attack. Call your local emergency number right away.

Stable Angina

The pain or discomfort:

• Occurs when the heart must work harder, usually during physical exertion
• Doesn’t come as a surprise, and episodes of pain tend to be alike
• Usually lasts a short time (5 minutes or less)
• Is relieved by rest or medicine
• May feel like gas or indigestion
• May feel like chest pain that spreads to the arms, back, or other areas.

Unstable Angina

The pain or discomfort:

• Often occurs at rest, while sleeping at night, or with little physical exertion
• Comes as a surprise
• Is more severe and lasts longer than stable angina (as long as 30 minutes)
• Usually isn’t relieved by rest or medicine
• May get worse over time
• May mean that a heart attack will happen soon.

Variant Angina

The pain or discomfort:

• Usually occurs at rest and during the night or early morning hours
• Tends to be severe
• Is relieved by medicine.

Microvascular Angina

The pain or discomfort:

• May be more severe and last longer than other types of angina pain
• May occur with shortness of breath, sleep problems, fatigue, and lack of energy
• Often is first noticed during routine daily activities and times of mental stress.

How is Angina Diagnosed ?

The most important issues to address when you go to the doctor with chest pain are:

• What’s causing the chest pain
• Whether you’re having or are about to have a heart attack.

Angina is a symptom of an underlying heart problem, usually coronary heart disease ⁴⁶. The type of angina pain you have can be a sign of how severe the coronary heart disease is and whether it’s likely to cause a heart attack.

If you have chest pain, your doctor will want to find out whether it’s angina. He or she also will want to know whether the angina is stable or unstable. If it’s unstable, you may need emergency medical treatment to try to prevent a heart attack.

To diagnose chest pain as stable or unstable angina, your doctor will do a physical exam, ask about your symptoms, and ask about your risk factors for and your family history of coronary heart disease or other heart diseases.

Your doctor also may ask questions about your symptoms, such as:

• What brings on the pain or discomfort and what relieves it?
• What does the pain or discomfort feel like (for example, heaviness or tightness)?
• How often does the pain occur?
• Where do you feel the pain or discomfort?
• How severe is the pain or discomfort?
• How long does the pain or discomfort last?

Diagnostic Tests and Procedures

If your doctor thinks that you have unstable angina or that your angina is related to a serious heart condition, he or she may recommend one or more tests.

• EKG (Electrocardiogram)

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 due to coronary heart disease and signs of a previous or current heart attack. However, some people who have angina have normal EKGs.

• Stress Testing

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 and beating fast, 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 coronary heart disease, such as:

• Abnormal changes in your heart rate or blood pressure
• Shortness of breath or chest pain
• Abnormal changes in your heart rhythm or your heart’s electrical activity

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.

• Chest X Ray

A chest x ray takes pictures of the organs and structures inside your chest, such as your heart, lungs, and blood vessels.

A chest x ray can reveal signs of heart failure. It also can show signs of lung disorders and other causes of symptoms not related to coronary heart disease. However, a chest x ray alone is not enough to diagnose angina or coronary heart disease.

• Coronary Angiography and Cardiac Catheterization

Your doctor may recommend coronary angiography if he or she suspects you have coronary heart disease. This test uses dye and special x rays to show the inside of your coronary arteries.

To get the dye into your coronary arteries, your doctor will use a procedure called cardiac catheterization.

A thin, flexible tube called a catheter is put into a blood vessel in your arm, groin (upper thigh), or neck. The tube is threaded into your coronary arteries, and the dye is released into your bloodstream.

Special x rays are taken while the dye is flowing through your coronary arteries. The dye lets your doctor study the flow of blood through your heart and blood vessels.

Cardiac catheterization usually is done in a hospital. You’re awake during the procedure. It usually causes little or no pain, although you may feel some soreness in the blood vessel where your doctor inserts the catheter.

Computed Tomography Angiography

Computed tomography angiography uses dye and special x rays to show blood flow through the coronary arteries. This test is less invasive than coronary angiography with cardiac catheterization.

For computed tomography angiography, a needle connected to an intravenous (IV) line is put into a vein in your hand or arm. Dye is injected through the IV line during the scan. You may have a warm feeling when this happens. The dye highlights your blood vessels on the CT scan pictures.

Sticky patches called electrodes are put on your chest. The patches are attached to an EKG machine to record your heart’s electrical activity during the scan.

The CT scanner is a large machine that has a hollow, circular tube in the middle. You lie on your back on a sliding table. The table slowly slides into the opening of the machine.

Inside the scanner, an x-ray tube moves around your body to take pictures of different parts of your heart. A computer puts the pictures together to make a three-dimensional (3D) picture of the whole heart.

• Blood Tests

Blood tests check the levels of certain fats, cholesterol, sugar, and proteins in your blood. Abnormal levels may show that you have risk factors for coronary heart disease.

Your doctor may recommend a blood test to check the level of a protein called C-reactive protein (CRP) in your blood. Some studies suggest that high levels of CRP in the blood may increase the risk for coronary heart disease and heart attack.

Your doctor also may recommend a blood test to check for low levels of hemoglobin your blood. Hemoglobin is an iron-rich protein in red blood cells. It helps the blood cells carry oxygen from the lungs to all parts of your body. If your hemoglobin level is low, you may have a condition called anemia.

How is Angina Treated ?

Treatments for angina include lifestyle changes, medicines, medical procedures, cardiac rehabilitation (rehab), and other therapies ⁴⁷. The main goals of treatment are to:

• Reduce pain and discomfort and how often it occurs
• Prevent or lower your risk for heart attack and death by treating your underlying heart condition.

Lifestyle changes and medicines may be the only treatments needed if your symptoms are mild and aren’t getting worse. If lifestyle changes and medicines don’t control angina, you may need medical procedures or cardiac rehab.

Unstable angina is an emergency condition that requires treatment in a hospital.

Lifestyle Changes

Making lifestyle changes can help prevent episodes of angina. You can:

• Slow down or take rest breaks if physical exertion triggers angina.
• Avoid large meals and rich foods that leave you feeling stuffed if heavy meals trigger angina.
• Try to avoid situations that make you upset or stressed if emotional stress triggers angina. Learn ways to handle stress that can’t be avoided.

You also can make lifestyle changes that help lower your risk for coronary heart disease. One of the most important changes is to quit smoking. Smoking can damage and tighten blood vessels and raise your risk for coronary heart disease. 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.

Following a healthy diet is another important lifestyle change. A healthy diet can prevent or reduce high blood pressure and high blood cholesterol and help you maintain a healthy weight.

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 also is low in sodium (salt), added sugars, solid fats, and refined grains.

For more information about following a healthy diet, go to:

• What is the DASH Diet ?
• Healthy Eating
• Healthy Foods

Other important lifestyle changes include:

• Being physically active. Check with your doctor to find out how much and what kinds of activity are safe for you. For more information, go to the Healthy Exercise article.
• Maintaining a healthy weight. If you’re overweight or obese, work with your doctor to create a reasonable weight-loss plan. Controlling your weight helps you control coronary heart disease risk factors.
• Taking all medicines as your doctor prescribes, especially if you have diabetes.

Medicines

Nitrates are the medicines most commonly used to treat angina. They relax and widen blood vessels. This allows more blood to flow to the heart, while reducing the heart’s workload.

Nitroglycerin is the most commonly used nitrate for angina. Nitroglycerin that dissolves under your tongue or between your cheek and gum is used to relieve angina episodes.

Nitroglycerin pills and skin patches are used to prevent angina episodes. However, pills and skin patches act too slowly to relieve pain during an angina attack.

Other medicines also are used to treat angina, such as beta blockers, calcium channel blockers, ACE inhibitors, oral antiplatelet medicines, or anticoagulants (blood thinners). These medicines can help:

• Lower blood pressure and cholesterol levels
• Slow the heart rate
• Relax blood vessels
• Reduce strain on the heart
• Prevent blood clots from forming

People who have stable angina may be advised to get annual flu shots.

Medical Procedures

If lifestyle changes and medicines don’t control angina, you may need a medical procedure to treat the underlying heart disease. Both angioplasty and coronary artery bypass grafting (CABG) are commonly used to treat heart disease.

Angioplasty opens blocked or narrowed coronary arteries. During angioplasty, a thin tube with a balloon or other device on the end is threaded through a blood vessel to the narrowed or blocked coronary artery.

Once in place, the balloon is inflated to push the plaque outward against the wall of the artery. This widens the artery and restores blood flow.

Angioplasty can improve blood flow to your heart and relieve chest pain. A small mesh tube called a stent usually is placed in the artery to help keep it open after the procedure.

During CABG, healthy arteries or veins taken from other areas in your body are used to bypass (that is, go around) your narrowed coronary arteries. Bypass surgery can improve blood flow to your heart, relieve chest pain, and possibly prevent a heart attack.

You will work with your doctor to decide which treatment is better for you.

Cardiac Rehabilitation

Your doctor may recommend cardiac rehab for angina or after angioplasty, CABG, or a heart attack. Cardiac rehab is a medically supervised program that can help improve the health and well-being of people who have heart problems.

The cardiac rehab team may include doctors, nurses, exercise specialists, physical and occupational therapists, dietitians or nutritionists, and psychologists or other mental health specialists.

Rehab has two parts:

1. Exercise training. This part helps you learn how to exercise safely, strengthen your muscles, and improve your stamina. Your exercise plan will be based on your personal abilities, needs, and interests.
2. Education, counseling, and training. This part of rehab helps you understand your heart condition and find ways to reduce your risk for future heart problems. The rehab team will help you learn how to adjust to a new lifestyle and deal with your fears about the future.

Enhanced External Counterpulsation Therapy

Enhanced external counterpulsation therapy is helpful for some people who have angina. Large cuffs, similar to blood pressure cuffs, are put on your legs. The cuffs are inflated and deflated in sync with your heartbeat ⁴⁷.

Enhanced external counterpulsation therapy improves the flow of oxygen-rich blood to your heart muscle and helps relieve angina. You typically get 35 1-hour treatments over 7 weeks ⁴⁷.

What Causes Angina ?

Angina usually is a symptom of coronary heart disease ⁴⁸. This means that the underlying causes of angina generally are the same as the underlying causes of coronary heart disease.

Research suggests that coronary heart disease starts when certain factors damage the inner layers of the coronary arteries. These factors include:

• Smoking
• High amounts of certain fats and cholesterol in the blood
• High blood pressure
• High amounts of sugar in the blood due to insulin resistance or diabetes

Plaque may begin to build up where the arteries are damaged. When plaque builds up in the arteries, the condition is called atherosclerosis.

Plaque narrows or blocks the arteries, reducing blood flow to the heart muscle. Some plaque is hard and stable and causes the arteries to become narrow and stiff. This can greatly reduce blood flow to the heart and cause angina.

Other plaque is soft and more likely to rupture (break open) and cause blood clots. Blood clots can partially or totally block the coronary arteries and cause angina or a heart attack.

• Immediate Causes

Many factors can trigger angina pain, depending on the type of angina you have.

Stable Angina

Physical exertion is the most common trigger of stable angina. Severely narrowed arteries may allow enough blood to reach the heart when the demand for oxygen is low, such as when you’re sitting.

However, with physical exertion—like walking up a hill or climbing stairs—the heart works harder and needs more oxygen.

Other triggers of stable angina include:

• Emotional stress
• Exposure to very hot or cold temperatures
• Heavy meals
• Smoking

Unstable Angina

Blood clots that partially or totally block an artery cause unstable angina.

If plaque in an artery ruptures, blood clots may form. This creates a blockage. A clot may grow large enough to completely block the artery and cause a heart attack.

Blood clots may form, partially dissolve, and later form again. Angina can occur each time a clot blocks an artery.

Variant Angina

A spasm in a coronary artery causes variant angina. The spasm causes the walls of the artery to tighten and narrow. Blood flow to the heart slows or stops. Variant angina can occur in people who have coronary heart disease and in those who don’t.

The coronary arteries can spasm as a result of:

• Exposure to cold
• Emotional stress
• Medicines that tighten or narrow blood vessels
• Smoking
• Cocaine use

Microvascular Angina

This type of angina may be a symptom of coronary microvascular disease. Coronary microvascular disease is heart disease that affects the heart’s smallest coronary arteries.

Reduced blood flow in the small coronary arteries may cause microvascular angina. Plaque in the arteries, artery spasms, or damaged or diseased artery walls can reduce blood flow through the small coronary arteries.

How can Angina Be Prevented ?

You can prevent or lower your risk for angina and heart disease by making lifestyle changes and treating related conditions ⁴⁹.

Making Lifestyle Changes

Healthy lifestyle choices can help prevent or delay angina and heart disease. To adopt a healthy lifestyle, you can:

• Quit smoking and avoid secondhand smoke
• Avoid angina triggers
• Follow a healthy diet
• Be physically active
• Maintain a healthy weight
• Learn ways to handle stress and relax
• Take your medicines as your doctor prescribes

Treating Related Conditions

You also can help prevent or delay angina and heart disease by treating related conditions, such as high blood cholesterol, high blood pressure, diabetes, and overweight or obesity.

If you have one or more of these conditions, talk with your doctor about how to control them. Follow your treatment plan and take all of your medicines as your doctor prescribes.

Living With Angina

Angina isn’t a heart attack, but it does increase your risk of having a heart attack ⁵⁰. The risk is even higher if you have unstable angina. For these reasons, it’s important that you know:

• The usual pattern of your angina, if you have it regularly.
• What medicines you take (keep a list) and how to take them. Make sure your medicines are readily available.
• How to control your angina.
• The limits of your physical activity.
• How and when to seek medical attention.

Know the Pattern of Your Angina

Stable angina usually occurs in a pattern. You should know:

• What causes the pain to occur
• What the pain feels like
• How long the pain usually lasts
• Whether rest or medicine relieves the pain

After several episodes, you’ll learn the pattern of your angina. You’ll want to pay attention to whether the pattern changes. Pattern changes may include angina that occurs more often, lasts longer, is more severe, occurs without physical exertion, or doesn’t go away with rest or medicines.

These changes may be a sign that your symptoms are getting worse or becoming unstable. You should seek medical help. Unstable angina suggests that you’re at high risk for a heart attack very soon.

Know Your Medicines

You should know what medicines you’re taking, the purpose of each, how and when to take them, and possible side effects. Know exactly when and how to take fast-acting nitroglycerin or other nitrates to relieve chest pain.

Correctly storing your angina medicines and knowing when to replace them also is important. Your doctor can advise you about this.

If you have side effects from your medicines, let your doctor know. You should never stop taking your medicines without your doctor’s approval.

Talk with your doctor if you have any questions or concerns about taking your angina medicines. Tell him or her about any other medicines you’re taking. Some medicines can cause serious problems if they’re taken with nitrates or other angina medicines.

Know How To Control Your Angina

After several angina episodes, you’ll know the level of activity, stress, and other factors that trigger your angina. By knowing this, you can take steps to prevent or lessen the severity of episodes.

Physical Exertion

Know what level of physical exertion triggers your angina and try to stop and rest before chest pain starts. For example, if walking up a flight of stairs leads to chest pain, stop halfway and rest before continuing.

If chest pain occurs during physical exertion, stop and rest or take your angina medicine. The pain should go away in a few minutes. If the pain doesn’t go away or lasts longer than usual, call your local emergency number for emergency care.

Emotional Stress

Anger, arguing, and worrying are examples of emotional stress that can trigger angina. Try to avoid or limit situations that cause these emotions.

Exercise and relaxation can help relieve stress. Alcohol and drug use play a part in causing stress and don’t relieve it. If stress is a problem for you, talk with your doctor about getting help for it.

Eating Large Meals

If large meals lead to chest pain, eat smaller meals. Also, avoid eating rich foods.

Know the Limits of Your Physical Activity

Most people who have stable angina can continue their normal activities. This includes work, hobbies, and sexual relations. However, if you do very strenuous activities or have a stressful job, talk with your doctor.

Know How and When To Seek Medical Attention

Angina increases your risk for a heart attack. It’s important that you and your family know how and when to seek medical attention.

Talk with your doctor about making an emergency action plan. The plan should include making sure you and your family members know:

• The signs and symptoms of a heart attack
• How to use aspirin and nitroglycerin when needed
• How to access emergency medical services in your community
• The location of the nearest hospital that offers 24-hour emergency heart care

Discuss your emergency plan with your family members. Take action quickly if your chest pain becomes severe, lasts longer than a few minutes, or isn’t relieved by rest or medicine.

Sometimes it’s hard to tell the difference between unstable angina and a heart attack. Both are emergencies, so you should call local emergency number right away.

What is Coronary Microvascular Disease ?

Coronary microvascular disease (MVD) is also called nonobstructive coronary heart disease or cardiac syndrome X. Coronary microvascular disease (MVD) is a heart disease that affects the tiny coronary (heart) arteries. In coronary microvascular disease, the walls of the heart’s tiny arteries are damaged or diseased ⁵¹.

Coronary microvascular disease is different from traditional coronary heart disease, also called coronary artery disease. In coronary heart disease, a waxy substance called plaque builds up in the large coronary arteries. The plaque narrows the heart’s large arteries and reduces the flow of oxygen-rich blood to your heart muscle. The buildup of plaque also makes it more likely that blood clots will form in your arteries. Blood clots can mostly or completely block blood flow through a coronary artery.

In coronary microvascular disease, however, the heart’s tiny arteries are affected. Plaque doesn’t create blockages in these vessels as it does in the heart’s large arteries ⁵¹.

Coronary microvascular disease can affect both men and women. Both men and women who have coronary microvascular disease often have diabetes or high blood pressure (hypertension). Some people who have coronary microvascular disease may have inherited heart muscle diseases ⁵¹.

However, women may be at risk for coronary microvascular disease if they have lower than normal levels of estrogen at any point in their adult lives. This refers to the estrogen that the ovaries produce, not the estrogen used in hormone therapy ⁵². Low estrogen levels before menopause can raise younger women’s risk for the disease. Causes of low estrogen levels in younger women can be mental stress or a problem with the function of the ovaries.

Diagnosing coronary microvascular disease has been a challenge for doctors. Standard tests used to diagnose coronary heart disease aren’t designed to detect coronary microvascular disease. More research is needed to find the best diagnostic tests and treatments for the disease ⁵¹.

If you have coronary microvascular disease, you can take action to control it. Follow the steps described in “How can Coronary Microvascular Disease Be Prevented ?”

Coronary microvascular disease, like traditional coronary heart disease, increases your risk for a heart attack. If you have signs or symptoms of a heart attack, call local emergency number at once.

These signs and symptoms may include chest pain, upper body discomfort, shortness of breath, and nausea (feeling sick to your stomach). For more detailed information about the warning signs of a heart attack, go to the section on warning signs of a heart attack.

Ongoing Care

If you have coronary microvascular disease, see your doctor regularly to make sure the disease isn’t getting worse. Work with your doctor to keep track of your cholesterol, blood pressure, and blood sugar levels. This will help your doctor adjust your treatment as needed.

You may need to see a cardiologist (heart specialist) in addition to your primary care doctor. Talk with your doctor about how often you should schedule office visits or blood tests. Between those visits, call your doctor if you have any new symptoms or your symptoms worsen.

You should:

• Know your symptoms and how and when to seek medical help.
• Be able to describe the usual pattern of your symptoms.
• Know which medicines you take and when and how to take them.
• Know how to control your symptoms, including angina.
• Know the limits of your physical activity.
• Learn ways to avoid or cope with stress.

Warning Signs of a Heart Attack

If you have coronary microvascular disease, learn the warning signs of a heart attack ⁵³. The signs and symptoms of a heart attack include:

• Chest pain or discomfort. This involves uncomfortable pressure, squeezing, fullness, or pain in the center or left side of the chest that can be mild or strong. This pain or discomfort often lasts more than a few minutes or goes away and comes back.
• Upper body discomfort in one or both arms, the back, neck, jaw, or upper part of the stomach.
• Shortness of breath, which may occur with or before chest discomfort.
• Nausea (feeling sick to your stomach), vomiting, light-headedness or fainting, or breaking out in a cold sweat.
• Sleep problems, fatigue (tiredness), and lack of energy.

If you think you’re having a heart attack, call local emergency number at once. Early treatment can prevent or limit damage to your heart muscle. Do not drive to the hospital or let someone else drive you. Instead, call an ambulance so that medical personnel can begin life-saving treatment on the way to the emergency room.

• Let the people you see regularly know you’re at risk for a heart attack. They can seek emergency care if you suddenly faint, collapse, or have other severe symptoms.

What Causes Coronary Microvascular Disease ?

The same risk factors that cause atherosclerosis may cause coronary microvascular disease. Atherosclerosis is a disease in which plaque builds up inside the arteries.

Risk factors for atherosclerosis include:

• Diabetes. It is a disease in which the body’s blood sugar level is too high because the body doesn’t make enough insulin or doesn’t use its insulin properly.

• Family history of early heart disease. Your risk of atherosclerosis increases if your father or a brother was diagnosed with heart disease before age 55, or if your mother or a sister was diagnosed with heart disease before age 65.

• High blood pressure. Blood pressure is considered high if it stays at or above 140/90 mmHg over time. If you have diabetes or chronic kidney disease, high blood pressure is defined as 130/80 mmHg or higher. (The mmHg is millimeters of mercury—the units used to measure blood pressure.)

• Insulin resistance. This condition occurs if the body can’t use its insulin properly. Insulin is a hormone that helps move blood sugar into cells where it’s used for energy. Overtime, insulin resistance can lead to diabetes.

• Lack of physical activity. Physical inactivity can worsen some other risk factors for atherosclerosis, such as unhealthy blood cholesterol levels, high blood pressure, diabetes, and overweight or obesity.

• Older age. As you age, your risk for atherosclerosis increases. The process of atherosclerosis begins in youth and typically progresses over many decades before disease develops.

• Overweight and obesity. The terms “overweight” and “obesity” refer to body weight that’s greater than what is considered healthy for a certain height.

• Smoking. Smoking can damage and tighten blood vessels, lead to unhealthy cholesterol levels, and raise blood pressure. Smoking also doesn’t allow enough oxygen to reach the body’s tissues.

• Unhealthy blood cholesterol levels. This includes high LDL (“bad”) cholesterol and low HDL (“good”) cholesterol.

• Unhealthy diet. An unhealthy diet can raise your risk for atherosclerosis. Foods that are high in saturated and trans fats, cholesterol, sodium (salt), and sugar can worsen other risk factors for atherosclerosis.

In women, coronary microvascular disease also may be linked to low estrogen levels occurring before or after menopause ⁵⁴. Also, the disease may be linked to anemia or conditions that affect blood clotting ⁵⁴. Anemia is thought to slow the growth of cells needed to repair damaged blood vessels.

Researchers continue to explore other possible causes of coronary microvascular disease.

Figure 4. Coronary Microvascular Disease

[Source ⁵¹]

Note: A shows the small coronary artery network (microvasculature), containing a normal artery and an artery with coronary microvascular disease. B shows a large coronary artery with plaque buildup.

What are the Signs and Symptoms of Coronary Microvascular Disease ?

The signs and symptoms of coronary microvascular disease often differ from the signs and symptoms of traditional coronary heart disease (CHD).

Many women with coronary microvascular disease have 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.

Angina also is a common symptom of coronary heart disease. However, the angina that occurs in coronary microvascular disease may differ from the typical angina that occurs in coronary heart disease ⁵⁵. In coronary microvascular disease, the chest pain usually lasts longer than 10 minutes, and it can last longer than 30 minutes. Typical angina is more common in women older than 65 ⁵⁵.

Other signs and symptoms of coronary microvascular disease are shortness of breath, sleep problems, fatigue (tiredness), and lack of energy ⁵⁵.

Coronary microvascular disease symptoms often are first noticed during routine daily activities (such as shopping, cooking, cleaning, and going to work) and times of mental stress. It’s less likely that women will notice these symptoms during physical activity (such as jogging or walking fast) ⁵⁵.

This differs from coronary heart disease, in which symptoms often first appear while a person is being physically active—such as while jogging, walking on a treadmill, or going up stairs.

How is Coronary Microvascular Disease Diagnosed ?

Your doctor will diagnose coronary microvascular disease based on your medical history, a physical exam, and test results. He or she will check to see whether you have any risk factors for heart disease.

For example, your doctor may measure your weight and height to check for overweight or obesity. He or she also may recommend tests for high blood cholesterol, metabolic syndrome, and diabetes.

Your doctor may ask you to describe any chest pain, including when it started and how it changed during physical activity or periods of stress. He or she also may ask about other symptoms, such as fatigue (tiredness), lack of energy, and shortness of breath. Women may be asked about their menopausal status.

Specialists Involved

Cardiologists and doctors who specialize in family and internal medicine might help diagnose and treat coronary microvascular disease. Cardiologists are doctors who specialize in diagnosing and treating heart diseases and conditions.

Diagnostic Tests

The risk factors for coronary microvascular disease and traditional coronary heart disease often are the same ⁵⁶. Thus, your doctor may recommend tests for coronary heart disease, such as:

• Coronary angiography. This test uses dye and special x-rays to show the insides of your coronary arteries. Coronary angiography can show plaque buildup in the large coronary arteries. This test often is done during a heart attack to help find blockages in the coronary arteries.
• Stress testing. This test shows how blood flows through your heart during physical stress, such as exercise. Even if coronary angiography doesn’t show plaque buildup in the large coronary arteries, a stress test may still show abnormal blood flow. This may be a sign of coronary microvascular disease.
• Cardiac MRI (magnetic resonance imaging) stress test. Doctors may use this test to evaluate people who have chest pain.

Unfortunately, standard tests for coronary heart disease aren’t designed to detect coronary microvascular disease. These tests look for blockages in the large coronary arteries. Coronary microvascular disease affects the tiny coronary arteries.

If test results show that you don’t have coronary heart disease, your doctor might still diagnose you with coronary microvascular disease. This could happen if signs are present that not enough oxygen is reaching your heart’s tiny arteries.

Coronary microvascular disease symptoms often first occur during routine daily tasks. Thus, your doctor may ask you to fill out a questionnaire called the Duke Activity Status Index. The questionnaire will ask you how well you’re able to do daily activities, such as shopping, cooking, and going to work.

The Duke Activity Status Index results will help your doctor decide which kind of stress test you should have. The results also give your doctor information about how well blood is flowing through your coronary arteries.

Your doctor also may recommend blood tests, including a test for anemia. Anemia is thought to slow the growth of cells needed to repair damaged blood vessels.

Research is ongoing for better ways to detect and diagnose coronary microvascular disease. Currently, researchers have not agreed on the best way to diagnose the disease.

How is Coronary Microvascular Disease Treated ?

Relieving pain is one of the main goals of treating coronary microvascular disease. Treatments also are used to control risk factors and other symptoms.

Treatments may include medicines ⁵⁷, such as:

• ACE inhibitors and beta blockers to lower blood pressure and decrease the heart’s workload
• Aspirin to help prevent blood clots or control inflammation
• Nitroglycerin to relax blood vessels, improve blood flow to the heart muscle, and treat chest pain
• Statin medicines to control or lower your blood cholesterol.

Take all medicines regularly, as your doctor prescribes. Don’t change the amount of your medicine or skip a dose unless your doctor tells you to.

If you’re diagnosed with coronary microvascular disease and also have anemia, you may benefit from treatment for that condition. Anemia is thought to slow the growth of cells needed to repair damaged blood vessels.

If you’re diagnosed with and treated for coronary microvascular disease, you should get ongoing care from your doctor. Research is under way to find the best treatments for coronary microvascular disease.

How can Coronary Microvascular Disease Be Prevented ?

No specific studies have been done on how to prevent coronary microvascular disease ⁵⁸.

Researchers don’t yet know how or in what way preventing coronary microvascular disease differs from preventing coronary heart disease. Coronary microvascular disease affects the tiny coronary arteries; coronary heart disease affects the large coronary arteries.

Taking action to control risk factors for heart disease can help prevent or delay coronary heart disease. You can’t control some risk factors, such as older age and family history of heart disease. However, you can take steps to prevent or control other risk factors, such as high blood pressure, overweight and obesity, high blood cholesterol, diabetes, and smoking.

Heart-healthy lifestyle changes and ongoing medical care can help you lower your risk for heart disease.

Heart-Healthy Lifestyle Changes

Your doctor may recommend heart-healthy lifestyle changes if you have coronary microvascular disease. Heart-healthy lifestyle changes include:

• Heart-healthy eating
• Maintaining a healthy weight
• Managing stress
• Physical activity
• Quit smoking

Heart-Healthy Eating

Your doctor may recommend a heart-healthy eating plan, which should include:

• Fat-free or low-fat dairy products, such as skim milk
• Fish high in omega-3 fatty acids, such as salmon, tuna, and trout, about twice a week
• Fruits, such as apples, bananas, oranges, pears, and prunes
• Legumes, such as kidney beans, lentils, chickpeas, black-eyed peas, and lima beans
• Vegetables, such as broccoli, cabbage, and carrots
• Whole grains, such as oatmeal, brown rice, and corn tortillas.

When following a heart-healthy diet, you should avoid eating:

• A lot of red meat
• Palm and coconut oils
• Sugary foods and beverages

Two nutrients in your diet make blood cholesterol levels rise:

• Saturated fat—found mostly in foods that come from animals
• Trans fat (trans fatty acids)—found in foods made with hydrogenated oils and fats, such as stick margarine; baked goods, such as cookies, cakes, and pies; crackers; frostings; and coffee creamers. Some trans fats also occur naturally in animal fats and meats.

Saturated fat raises your blood cholesterol more than anything else in your diet. When you follow a heart-healthy eating plan, only 5 percent to 6 percent of your daily calories should come from saturated fat. Food labels list the amounts of saturated fat.

Not all fats are bad. Monounsaturated and polyunsaturated fats actually help lower blood cholesterol levels.

Some sources of monounsaturated and polyunsaturated fats are:

• Avocados
• Corn, sunflower, and soybean oils
• Nuts and seeds, such as walnuts
• Olive, canola, peanut, safflower, and sesame oils
• Peanut butter
• Salmon and trout
• Tofu

Sodium (salt)

You should try to limit the amount of sodium that you eat. This means choosing and preparing foods that are lower in salt and sodium. Try to use low-sodium and “no added salt” foods and seasonings at the table or while cooking. Food labels tell you what you need to know about choosing foods that are lower in sodium. Try to eat no more than 2,300 milligrams of sodium a day. If you have high blood pressure, you may need to restrict your sodium intake even more.

Dietary Approaches to Stop Hypertension

Your doctor may recommend the Dietary Approaches to Stop Hypertension (DASH) eating plan if you have high blood pressure. The Dietary Approaches to Stop Hypertension (DASH) eating plan focuses on fruits, vegetables, whole grains, and other foods that are heart healthy and low in fat, cholesterol, and sodium and salt.

The Dietary Approaches to Stop Hypertension (DASH) eating plan is a good heart-healthy eating plan, even for those who don’t have high blood pressure. Read more about Dietary Approaches to Stop Hypertension (DASH) by going to What is the DASH Diet ?.

Alcohol

Try to limit alcohol intake. Too much alcohol can raise your blood pressure and triglyceride levels, a type of fat found in the blood. Alcohol also adds extra calories, which may 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:

• 12 ounces of beer
• 5 ounces of wine
• 1½ ounces of liquor

Maintaining a Healthy Weight

Maintaining a healthy weight is important for overall health and can lower your risk for coronary heart disease. Aim for a Healthy Weight by following a heart-healthy eating plan and keeping physically active.

Knowing your body mass index (BMI) helps you find out if you’re a healthy weight in relation to your height and gives an estimate of your total body fat. To figure out your body mass index (BMI), you can use a FREE online BMI calculators from the Centers for Disease Control and Prevention (CDC) :

• Adults ¹⁹

For children and adolescents (younger than 20 years of age), overweight and obesity are based on the Centers for Disease Control and Prevention’s (CDC’s) BMI-for-age growth charts, which are available at ²⁰.

The CDC has a BMI percentile calculator for children and teens at ²¹.

• Children ²²

Body Mass Index for Men and Women Adults

The body mass index is an attempt to quantify the amount of tissue mass (muscle, fat, and bone) in an individual, and then categorize that person as underweight, normal weight, overweight, or obese based on that value. Commonly accepted body mass index ranges are:

A) Underweight: under 18.5 kg/m²,

B) Normal weight: 18.5 to 25 kg/m²,

C) Overweight: 25 to 30 kg/m²,

D) Obese: over 30 to 39.9 kg/m².

E) Severely Obese: over 40 kg/m².

A general goal to aim for is a BMI below 25 kg/m². Your doctor or health care provider can help you set an appropriate BMI goal.

Measuring waist circumference helps screen for possible health risks. If most of your fat is around your waist rather than at your hips, you’re at a higher risk for heart disease and type 2 diabetes. This risk may be high with a waist size that is greater than 35 inches for women or greater than 40 inches for men. To learn how to measure your waist, visit Waist Hip Ratio.

If you’re overweight or obese, try to lose weight. A loss of just 3 percent to 5 percent of your current weight can lower your triglycerides, blood glucose, and the risk of developing type 2 diabetes. Greater amounts of weight loss can improve blood pressure readings, lower LDL cholesterol, and increase HDL cholesterol.

Managing Stress

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. Consider healthy stress-reducing activities, such as:

• A stress management program
• Meditation
• Physical activity
• Relaxation therapy
• Talking things out with friends or family

Physical Activity

Routine physical activity can lower many coronary heart disease 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 coronary heart disease.

Everyone should try to participate in moderate-intensity aerobic exercise at least 2 hours and 30 minutes per week, or vigorous aerobic exercise for 1 hour and 15 minutes per week. Aerobic exercise, such as brisk walking, is any exercise in which your heart beats faster and you use more oxygen than usual. The more active you are, the more you will benefit. Participate in aerobic exercise for at least 10 minutes at a time spread throughout the week.

Read more about physical activity at:

• The Truth About Exercise
• Healthy Exercise

Talk with your doctor before you start a new exercise plan. Ask your doctor how much and what kinds of physical activity are safe for you.

Quitting Smoking

If you smoke, quit. Smoking can raise your risk for coronary heart disease and heart attack and worsen other coronary heart disease risk factors. Talk with your doctor about programs and products that can help you quit smoking. 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.

Read more about quitting smoking at Smoking and Your Heart ⁵⁹.

Ongoing Medical Care

Learn more about heart disease and the traits, conditions, and habits that can raise your risk for developing it. Talk with your doctor about your risk factors for heart disease and how to control them.

If lifestyle changes aren’t enough, your doctor may prescribe medicines to control your risk factors. Take all of your medicines as your doctor advises. Visit your doctor regularly and have recommended testing.

Know your numbers. Ask your doctor for these three tests and have the results explained to you:

• Blood pressure measurement.
• Fasting blood glucose. This test is for diabetes.
• Lipoprotein panel. This test measures total cholesterol, LDL (“bad”) cholesterol, HDL (“good”) cholesterol, and triglycerides (a type of fat in the blood).

Finally, know your family history of heart disease. If you or someone in your family has heart disease, tell your doctor.

Outlook for coronary microvascular disease

Most of what is known about coronary microvascular disease comes from the National Heart, Lung, and Blood Institute’s Women’s Ischemia Syndrome Evaluation.

Currently, research is ongoing to learn more about the role of hormones in heart disease and to find better ways to diagnose coronary coronary microvascular disease.

Studies also are under way to learn more about the causes of coronary microvascular disease, how to treat the disease, and the expected health outcomes for people with coronary microvascular disease.

What is an arrhythmia ?

An arrhythmia is a problem with the rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm ⁶⁰. When the heart doesn’t beat properly, it can’t pump blood effectively. When the heart doesn’t pump blood effectively, the lungs, brain and all other organs can’t work properly and may shut down or be damaged ⁶¹.

A heartbeat that is too fast is called tachycardia. A heartbeat that is too slow is called bradycardia.

Most arrhythmias are harmless, but some can be serious or even life threatening. During an arrhythmia, the heart may not be able to pump enough blood to the body. Lack of blood flow can damage the brain, heart, and other organs.

Understanding the Heart’s Electrical System

To understand arrhythmias, it helps to understand the heart’s internal electrical system. The heart’s electrical system controls the rate and rhythm of the heartbeat.

With each heartbeat, an electrical signal spreads from the top of the heart to the bottom. As the signal travels, it causes the heart to contract and pump blood.

Your heart’s electrical system controls all the events that occur when your heart pumps blood ⁶². The electrical system also is called the cardiac conduction system. If you’ve ever seen the heart test called an EKG (electrocardiogram), you’ve seen a graphical picture of the heart’s electrical activity.

Your heart’s electrical system is made up of three main parts:

1. The Sinoatrial (SA) node, located in the right atrium of your heart
2. The Atrioventricular (AV) node, located on the interatrial septum close to the tricuspid valve
3. The His-Purkinje system, located along the walls of your heart’s ventricles

A heartbeat is a complex series of events. These events take place inside and around your heart. A heartbeat is a single cycle in which your heart’s chambers relax and contract to pump blood. This cycle includes the opening and closing of the inlet and outlet valves of the right and left ventricles of your heart.

Each heartbeat has two basic parts: diastole and systole. During diastole, the atria and ventricles of your heart relax and begin to fill with blood.

At the end of diastole, your heart’s atria contract (atrial systole) and pump blood into the ventricles. The atria then begin to relax. Your heart’s ventricles then contract (ventricular systole), pumping blood out of your heart.

Each electrical signal begins in a group of cells called the sinus node or sinoatrial (SA) node. The SA node is located in the heart’s upper right chamber, the right atrium. In a healthy adult heart at rest, the SA node fires off an electrical signal to begin a new heartbeat 60 to 100 times a minute. In a normal, healthy heart, each beat begins with a signal from the SA node. This is why the SA node sometimes is called your heart’s natural pacemaker. Your pulse, or heart rate, is the number of signals the SA node produces per minute.

The signal is generated as the vena cavae fill your heart’s right atrium with blood from other parts of your body. The signal spreads across the cells of your heart’s right and left atria.

From the SA node, the electrical signal travels through special pathways in the right and left atria. This causes the atria to contract and pump blood through the open valves from the atria into heart’s two lower chambers, the ventricles.

The electrical signal then moves down to a group of cells called the atrioventricular (AV) node, located between the atria and the ventricles. Here, the signal slows down just a little, allowing your heart’s right and left ventricles time to finish filling with blood.

The electrical signal then leaves the AV node and travels along a pathway called the bundle of His. This pathway divides into a right bundle branch and a left bundle branch. The signal goes down these branches to the ventricles, causing them to contract and pump blood to the lungs and the rest of the body.

From the bundle of His, the signal fibers divide into left and right bundle branches through the Purkinje fibers. These fibers connect directly to the cells in the walls of your heart’s left and right ventricles.

The signal spreads across the cells of your ventricle walls, and both ventricles contract. However, this doesn’t happen at exactly the same moment.

The left ventricle contracts an instant before the right ventricle. This pushes blood through the pulmonary valve (for the right ventricle) to your lungs, and through the aortic valve (for the left ventricle) to the rest of your body.

As the signal passes, the walls of the ventricles relax and await the next signal.

This process continues over and over as the atria refill with blood and more electrical signals come from the SA node.

A problem with any part of this process can cause an arrhythmia. For example, in atrial fibrillation, a common type of arrhythmia, electrical signals travel through the atria in a fast and disorganized way. This causes the atria to quiver instead of contract.

Figure 3. The heart’s electrical system

Outlook for arrhythmia

There are many types of arrhythmia. Most arrhythmias are harmless, but some are not. The outlook for a person who has an arrhythmia depends on the type and severity of the arrhythmia.

Even serious arrhythmias often can be successfully treated. Most people who have arrhythmias are able to live normal, healthy lives.

What is heart failure ?

Heart failure is a condition in which the heart can’t pump enough blood to meet the body’s needs ⁶³. In some cases, the heart can’t fill with enough blood. In other cases, the heart can’t pump blood to the rest of the body with enough force. Some people have both problems.

The term “heart failure” doesn’t mean that your heart has stopped or is about to stop working ⁶³. However, heart failure is a serious condition that requires medical care.

Other Names for Heart Failure

• Congestive heart failure.
• Left-side heart failure. This is when the heart can’t pump enough oxygen-rich blood to the body.
• Right-side heart failure. This is when the heart can’t fill with enough blood.
• Cor pulmonale. This term refers to right-side heart failure caused by high blood pressure in the pulmonary arteries and right ventricle (lower right heart chamber).

Overview

Heart failure develops over time as the heart’s pumping action grows weaker. The condition can affect the right side of the heart only, or it can affect both sides of the heart. Most cases involve both sides of the heart.

Right-side heart failure occurs if the heart can’t pump enough blood to the lungs to pick up oxygen. Left-side heart failure occurs if the heart can’t pump enough oxygen-rich blood to the rest of the body.

Right-side heart failure may cause fluid to build up in the feet, ankles, legs, liver, abdomen, and the veins in the neck. Right-side and left-side heart failure also may cause shortness of breath and fatigue (tiredness).

The leading causes of heart failure are diseases that damage the heart. Examples include coronary heart disease, high blood pressure, and diabetes.
Outlook

Heart failure is a very common condition. About 5.7 million people in the United States have heart failure ⁶³. Both children and adults can have the condition, although the symptoms and treatments differ ⁶³.

Currently, heart failure has no cure ⁶³. However, treatments—such as medicines and lifestyle changes—can help people who have the condition live longer and more active lives. Researchers continue to study new ways to treat heart failure and its complications.

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