Heart Attack

What is the Difference Between a Heart Attack and Sudden Cardiac Arrest?

According to the Centers for Disease Control and Prevention, someone in the U.S. has a heart attack every 40 seconds.1 That’s an estimated 790,000 Americans each year. Sudden cardiac arrest causes an estimated 350,000 deaths each year in the U.S. according to the American Heart Association.2 That’s about 1,000 people each day. To better understand the difference between a heart attack and sudden cardiac arrest, let’s begin with some heart basics.

Briefly, the role of the heart is to pump oxygen-rich blood and nutrients to all the organs and cells in the body and bring carbon dioxide and cellular wastes back to the heart. Carbon dioxide and cellular wastes are removed from the body and the blood is filled with oxygen (reoxygenated) and nutrients once again. This cycle repeats thousands of times each day. This system of blood circulation is called the circulatory system.

The heart pumps blood in a particular rhythm that is created by electrical signals sent from cell to cell across the heart muscle. In other words, the circulatory system is controlled by an electrical system generated from within the heart.

Both the terms heart attack and sudden cardiac arrest describe ways the heart can malfunction. A heart attack occurs when blood cannot flow through one or more of the coronary arteries, which supply oxygen and nutrients to the heart muscle. When this happens, the heart does not receive sufficient amounts of oxygen and nutrients and the heart tissue dies, causing a heart attack. A heart attack refers specifically to a problem with the circulatory system.

Sudden cardiac arrest occurs when the heart’s electrical system stops working. There are many causes for an electrical problem, but the most common are heart attack, changes in the structure of the heart due to a previous heart attack or heart disease, high blood pressure, and stress. When the heart experiences an electrical problem, it causes the heart to beat in an abnormal rhythm or to stop beating all together. Once the heart stops beating, it can no longer provide blood to the body and death can occur quickly. There are no telltale signs and symptoms of sudden cardiac arrest. Usually within seconds of an electrical problem, the person will lose consciousness and become unresponsive. It is essential to know the signs of both sudden cardiac arrest and heart attacks (listed below).

First Signs of Sudden Cardiac Arrest

  • Fainting
  • No pulse

Most Common Signs of Heart Attack

  • Chest pain
  • Shortness of breath
  • Pain in the arms, back, shoulders, jaw, neck, or stomach above the belly button
  • Unexplained tiredness (especially in women)
  • Nausea and vomiting
  • Feeling dizzy or lightheaded

It is important to note that the symptoms of a heart attack can differ greatly between men and women. In one out of five people, there are no signs and symptoms of a heart attack. Heart attacks can sometimes result in death, but often people are able to survive with proper treatment and lifestyle changes.

Immediate treatment is required for both sudden cardiac arrest and heart attacks. For sudden cardiac arrest an atrial defibrillation device or AED can be used to restart the electrical activity in the heart. If you or anyone you know suddenly loses consciousness and becomes unresponsive, first call 9-1-1 or your emergency response services immediately. Immediate treatment can save your life and limit the damage to your heart.

While you are waiting, persons trained in cardiopulmonary resuscitation or CPR may begin CPR. If there is more than one person available, one person can start CPR while the other looks for an AED. It is estimated that over 90% of people who have experienced sudden cardiac arrest will die before ever reaching emergency medical services. This is why it is so important learn emergency response techniques like CPR and how to use an AED to help those around you.

Here are some ways to improve your heart health:

  1. Eat a healthy diet. Consume lots of fruits, vegetables, beans, and whole grains. Limit your intake of saturated fat, cholesterol, and salt, such as in red meat and processed foods.
  2. Staying active helps keep your heart muscle strong.
  3. Make sure to see a doctor annually to check your heart health.
  4. Learn CPR and how to use an AED so you can help those around you.

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  1. “Heart Attack.” United States Centers for Disease Control and Prevention. https://www.cdc.gov/heartdisease/heart_attack.htm
  2. Benjamin, E. et al., (2019). Circulation, 139(10). 
  3. What is CPR? https://cpr.heart.org/en/resources/what-is-cpr