Cardiac Arrest

Cardiac arrest occurs when the heart suddenly stops functioning. With no effective heartbeat, the brain and other vital organs are deprived of blood, leading to death within minutes.

Cardiac arrest is not a heart attack. The heart usually continues beating during a heart attack. But cardiac arrest may occur as a result of a heart attack.

An estimated 250,000 to 450,000 Americans suffer cardiac arrest each year. Ninety-five percent die, often before receiving advanced medical attention.

What causes cardiac arrest?

Electrical signals in the heart synchronize heart function so that the heart beats properly and pumps blood through the body. Abnormal heart rhythms, called arrhythmias, can interfere with normal heart function.

Ventricular fibrillation is a dangerous type of arrhythmia and the most common cause of cardiac arrest. It makes the lower chambers of the heart beat rapidly or chaotically. Other types of electrical problems that can lead to cardiac arrest include electrical signals that slow and stop, or the heart muscle's inability to respond to electrical signals.

Who is at risk?

Men are twice as likely as women are to experience cardiac arrest. This condition is rare in children.

Parents may be concerned about reports of young athletes who die of cardiac arrest. Underlying heart problems and trauma that damages the heart can cause cardiac arrest in young athletes, although the risk is very low.

What are the risk factors?

Several factors can increase the risk for developing the electrical problems that can trigger cardiac arrest. These factors include:

• Coronary artery disease

• Heart attack

• Abnormal heart rhythms

• Heart failure

• A personal or family history of cardiac arrest or other genetic conditions that increase the risk for arrhythmias

• Changes in the heart structure

• Electrocution

• Drug abuse

• Excessive alcohol consumption

Cardiac arrest can also occur for no known reason.