What is a heart attack?

A heart attack occurs any time there is a shut off or there is a decline to the oxygen supply to the heart muscle. What this means is there is a mismatch between the amount of oxygen demanded and the supply. This can happen one of two different ways: The blood supply to the heart muscle can be cut off and trigger a heart attack; or, the demands of the heart muscle from physical distress can increase and the blood supply cannot rise, triggering a heart attack.

Sometimes referred to as a myocardial infarction (MI), a heart attack occurs when one of the arteries bringing blood to the heart is blocked by a blood clot or severe plaque. This can lead to permanent heart muscle damage if blood flow isn’t promptly restored.

Coronary arteries bring blood and oxygen to the heart. If blood flow to part of the heart is blocked long enough and the heart is starved of oxygen, heart cells die and that part of the heart muscle is damaged or dies, resulting in a heart attack—more formally known as myocardial infarction.

A heart attack occurs when blood flow to the heart muscle is blocked, resulting in dead heart muscle. A heart vessel may be narrowed by a cholesterol plaque, and if the plaque is unstable, the resulting inflammation can cause a blood clot. That blood clot blocks the blood flow to the muscle, which results in injury to the muscle.

This can kill the person in one of two ways:

  1. Lack of heart contraction causes the heart to no longer work as a pump.
  2. An irritation to the heart muscle occurs, which can cause very bad heart rhythms.
Dr. Sameer A. Sayeed, MD
Cardiologist (Heart Specialist)

A heart attack is due to a sudden lack of blood flow to a portion of the heart muscle, causing injury to that portion of heart muscle. It is usually caused by a blocked coronary artery that cuts off blood supply and thus oxygen to a certain part of the heart and, if it lasts long enough, leads to injury and eventual scarring of that portion of heart muscle supplied by the blocked artery. A heart attack can also occur when the heart beats so fast that it works beyond its blood and oxygen supply and sustains damage as a result.

A heart attack, or myocardial infarction, is damage to a portion of the heart muscle resulting from a total lack of blood supply to that area. Myocardial means "heart muscle" and infarction means "tissue death."

When the blood supply to the heart is cut off completely, the result is a heart attack. It can cause permanent damage to the heart muscle if blood flow is not restored as fast as possible. Typically, chest pain caused by a heart attack may be accompanied by discomfort in other areas of the upper body, indigestion, nausea, weakness and sweating. However, heart attack symptoms vary and may be mild. According to the American Heart Association, women are somewhat more likely than men to experience some of the symptoms other than chest pain, particularly shortness of breath, nausea/vomiting and back or jaw pain.

Symptoms that indicate your heart is in danger may be present for months or years before a heart attack occurs. Persistent unusual symptoms—shortness of breath, nausea, great fatigue, angina/chest pain, fainting spells and gas-like discomfort—may be red flags for heart disease. Discuss such symptoms with your healthcare professional, even if the symptoms come and go.

A heart attack occurs when blood flow to the heart is interrupted or reduced by blockage in the coronary artery. Without a constant blood supply, part of the heart can be injured and begin to die from not getting enough oxygen. A heart attack requires prompt treatment to prevent heart muscle from dying and scar tissue from forming.

Dr. Dede Bonner
Health Education Specialist

A heart attack happens when the blood flow to a section of your heart muscle becomes completely blocked. If the flow of blood isn’t restored quickly, the heart becomes starved for oxygen, is damaged, and begins to die. The medical terms for a heart attack are myocardial infarction, coronary thrombosis and coronary occlusion.

The main culprit in heart attacks is coronary artery disease (also called CAD), which results when a fatty material called plaque builds up over many years on the inside walls of your coronary arteries (the arteries that supply blood and oxygen to your heart). An area of plaque can rupture suddenly, causing a blood clot to form on the surface of the plaque. If the clot becomes large enough, it can block the flow of oxygen-rich blood to the heart.

The 10 Best Questions for Recovering from a Heart Attack: The Script You Need to Take Control of Your Health

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A good mind knows the right answers, but a great mind knows the right questions. And never are the Best Questions more important than after the life-altering event of surviving a heart attack or being diagnosed with heart disease. Drawing on cutting-edge research and advice from internationally prominent cardiologists, the president of the American Heart Association, award-winning personal trainers and nutritionists, and experts in healthy lifestyles, smoking cessation, alcohol abuse, stress management, spirituality, relationships, sex, and financial planning, The 10 Best Questions™ for Recovering from a Heart Attack is a holistic guide you'll take with you into your doctor's office and keep close to you through every step of your treatment and recovery. With a wealth of resources and up-to-the-minute information, The 10 Best Questions™ for Recovering from a Heart Attack shows you and your family how to move beyond your fears and use the power of the Best Questions and Magic Questions (the smartest questions most people never think to ask) to become your own best advocate for your physical, emotional, mental, spiritual, and financial health.
Eric Olsen
Fitness Specialist

A heart attack occurs when the blood flow to the heart is restricted so severely that the heart muscle is damaged. Most often, a heart attack occurs when a blood clot forms in an artery, entirely cutting off the flow of blood through that vessel. Blood clots naturally in the presence of foreign substances; unfortunately, sometimes the blood reacts to plaque deposits in the arteries as if they were foreign bodies, particularly when the deposits crack and damage the vessel walls, as sometimes happens when the artery is under unaccustomed pressure due to exertion or extreme emotion. Blood clots also tend to form where the flow of blood slows; for example, where thick deposits of plaque inside the arteries have formed. Blood clots rarely form in healthy arteries.

A heart attack can also occur when the coronary arteries go into spasm, often in the presence of atherosclerosis. More rarely, a piece of plaque inside the artery will break off and flow downstream to lodge where the artery narrows. And sometimes when the heart isn't getting the oxygen it needs because of narrowed coronary arteries, it will go into ventricular tachycardia, a rapid heartbeat, which can lead to fibrillation, an irregular beat, loss of consciousness, and even death.

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A heart attack happens when there is a blockage of one of the coronary arteries that supplies the heart. When this blockage occurs, the blood and oxygen supply to the heart muscle itself are stopped—and the heart muscle may then stop pumping blood to the brain and other body organs. Or, the heart may begin to have very irregular beats, letting you know that something is out of kilter. These problems are very serious, in fact, each of these problems can cause death if not corrected quickly. The most common cause of death early in a heart attack is from the irregular heart beats.

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Joan Haizlip, MSN
Cardiologist (Heart Specialist)

A heart attack means that part of your heart muscle is not getting enough oxygen and so a part of it becomes damaged. This is also called a myocardial infarction (MI).

Simply put, a heart attack is permanent damage to your heart muscle. A heart attack occurs when a blockage in one or more of your arteries prevents the blood that normally supplies oxygen and nutrients to the heart from making it to its destination. Without the oxygen and nutrients it needs, heart tissue is damaged or dies. Even if you survive a heart attack, your heart can sustain damage that puts you at greater risk for future heart attacks and limits your heart’s ability to support your former level of activity.

An extensive blockage, especially in a major blood vessel, such as the left anterior descending artery, can cause a large heart attack. Large heart attacks that are not treated early and aggressively can lead to heart failure. Certain types of heart failure have 5-year mortality rates of 50 percent or more, worse than many forms of cancer.

It is better to go to the hospital and learn that you are not having a heart attack than to stay home and have one. That’s because the consequences of an untreated heart attack are so great. If your symptoms persist for more than 15 minutes, you are at more risk that heart muscle cells will die. That's why every second counts when you have a heart attack. It is critical for you and your heart that you receive immediate medical attention.

To receive the best care, you have about 90 minutes from the onset of the heart attack for an interventional cardiologist or surgeon to restore the flow of blood to the heart before critical heart tissue dies or is damaged. Getting to a hospital that has the ability to perform a heart catheterization and angioplasty is the first, key step in obtaining the best treatment.

All it takes is an electrocardiogram (ECG or EKG)—a simple painless test—to find out if you’re having a heart attack. You can get one in the ambulance on your way to the hospital. It is a very effective way to reduce the time it takes to get you the treatment you need.

A heart attack occurs when the arteries are completely blocked and blood cannot get to the heart, depriving the heart of oxygen. When the heart is deprived of the oxygen it needs, its cells begin to die.

The chest pain often associated with heart attacks is how the hearts calls for help when it is dying.

A heart attack occurs when the muscle cells of the heart no longer function properly. This is usually due to an interruption of the blood flow to the heart muscle. The main cause of blood flow not reaching the heart cells is a ruptured plaque in the heart artery leading to the cells of the heart. The artery leading to the heart cells, "coronary artery" may suddenly become blocked off called "plaque rupture" and the blood flow stops to that area of the heart. The cells begin to swell and stop pumping when they run out of nutrients. This causes the patient to hurt in the chest and arms as well as feel short of breath. The cells may become electrically unstable and cause severe arrhythmias or "palpitations." Ventricular tachycardia or fibrillation are two of the most serious arrhythmias and may lead to the heart stopping suddenly—hence, the term "Sudden Death."

Emergency angioplasty/stent placement gives us the best chance to open the artery and restart the blood flow down the coronary artery. This increases the chance of survival, reduces the lifethreatening arrhythmias and helps avoid heart attack related heart failure. Hospitals around the world have worked to reduce the time it takes from the onset of chest pain to opening the artery of a heart attack victim. The result—mortality rates are down and more people are going home to their families!

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.