Alex Ehsan, MD, PhD · Medical search

Heart Attack

Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.

Source: MedlinePlus, National Library of Medicine. Read the original source

MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.

What is a heart attack?

A heart attack, also called a myocardial infarction, is a type of heart disease. It happens when blood flow to the heart suddenly becomes blocked. Without the blood coming in, the heart can't get oxygen. If not treated quickly, the heart muscle begins to die.

But if you get quick treatment, you may be able to prevent or limit damage to the heart muscle. That's why it's important to know the symptoms of a heart attack and call 911 if you or someone else is having them.

A heart attack is different than sudden cardiac arrest. During a heart attack, the heart usually doesn't suddenly stop beating. With a sudden cardiac arrest, the heart stops beating and the person passes out. A heart attack can trigger a sudden cardiac arrest. Both are medical emergencies.

If you are having symptoms of a heart attack, you should call 911, even if you are not sure it is a heart attack. Emergency medical services can start treatment as soon as they arrive, and calling 911 gets you care faster.

What heart attack risk factors can be changed?

There are many heart attack risk factors that you can change to lower your risk, which include:

What heart attack risk factors can't be changed?

There are other risk factors you can't change, which include:

What causes a heart attack?

The most common cause of heart attacks is coronary artery disease (CAD). With CAD, there is a buildup of cholesterol and other material, called plaque, on the inner walls or the arteries. This is atherosclerosis. It can build up for years. Eventually an area of plaque can rupture (break open). A blood clot can form around the plaque and block the artery.

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.

What are the symptoms of a heart attack?

Heart attack symptoms can vary from mild to severe. The symptoms one person has may not be the same as someone else's.

The most common symptoms include:

You may also have other symptoms, such as nausea, vomiting, dizziness, palpitations (racing or pounding heart), and lightheadedness. You may break out in a cold sweat. Sometimes women will have different symptoms then men. For example, they are more likely to feel tired for no reason.

How is a heart attack diagnosed?

At the hospital, health care providers make a diagnosis based on your symptoms, blood tests, and different heart imaging tests.

What is the treatment for a heart attack?

Treatments may include medicines including blood thinners to break up and prevent clots, oxygen therapy, and medical procedures such as coronary artery bypass surgery or coronary angioplasty, also known as percutaneous coronary intervention (PCI). After a heart attack, cardiac rehabilitation and lifestyle changes can help you recover.

Once you've had a heart attack, you have a higher risk of having another one. Talk to your provider about steps to take to lower your risk. These may include medicines and making lifestyle changes to improve your heart health.

NIH: National Heart, Lung, and Blood Institute

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