Survivor Stories
Meet local survivors of cardiac arrest.
“I was taking a martial arts class at Basalt Middle ... read more
Hector Vazquez, Survivor
“I’m a bit of a fitness nut, healthy eater, and... read more
“Undead Ed”, Survivor
“I suffered a cardiac arrest while at Little Annie’s... read more
Tom Clapper, Survivor

What Is Sudden Cardiac Arrest?

Sudden cardiac arrest (SCA) is a condition in which the heart suddenly and unexpectedly stops beating. If this happens, blood stops flowing to the brain and other vital organs. SCA usually causes death if it's not treated within minutes.

For more information visit The Sudden Cardiac Arrest Foundation web site.

What Causes Sudden Cardiac Arrest?

The heart has an electrical system that controls the rate and rhythm of the heartbeat. Problems with the heart's electrical system can cause irregular heartbeats called arrhythmias (ah-RITH-me-ahs).

During an arrhythmia, the heart can beat too fast, too slowly, or with an irregular rhythm. Some arrhythmias can cause the heart to stop pumping blood to the body—these arrhythmias cause SCA.

SCA is not the same as a heart attack.  A heart attack occurs if blood flow to part of the heart muscle is blocked. During a heart attack, the heart usually doesn't suddenly stop beating. SCA, however, may happen after or during recovery from a heart attack.
People who have heart disease are at higher risk for SCA. However, SCA can happen in people who appear healthy and have no known heart disease or other risk factors for SCA.

Who Is at Risk for Sudden Cardiac Arrest?

The risk of sudden cardiac arrest (SCA) increases with age. The risk also is higher if you have underlying heart disease. Men are two to three times more likely to have SCA than women.

SCA rarely occurs in children unless they have inherited problems that make them likely to have SCA. Only a very small number of children have SCA each year.

Major Risk Factors

The major risk factor for SCA is coronary artery disease (CHD). Most people who have SCA have some degree of CHD. However, these people may not know that they have CHD until SCA occurs.

For more information about CHD risk factors, go to the Diseases and Conditions Index Coronary Heart Disease Risk Factors article.

What Are the Signs and Symptoms of Sudden Cardiac Arrest?

Usually, the first sign of sudden cardiac arrest (SCA) is loss of consciousness (fainting). At the same time, no heartbeat (or pulse) can be felt. Some people may have a racing heartbeat or feel dizzy or light-headed just before they faint. Within an hour before SCA, some people have chest pain, shortness of breath, nausea (feeling sick to the stomach), or vomiting.


Most people who have SCA die from it—often within minutes. Rapid treatment of SCA with a defibrillator can be lifesaving.
Automated external defibrillators (AEDs) can be used by bystanders to save the lives of people who are having SCA.