Key points
- Sudden cardiac arrest occurs when the heart suddenly and unexpectedly stops beating.
- Sudden cardiac arrest is a medical emergency that can lead to death.
- If you believe someone is having a cardiac arrest, immediately call 911, start CPR, and use an AED.
What it is
When sudden cardiac arrest occurs, the heart stops pumping effectively and blood stops flowing to the rest of the body. A person experiencing sudden cardiac arrest is generally unresponsive and not breathing or is gasping for air. Sudden cardiac arrest can cause damage to the brain and internal organs. Immediate bystander action through CPR, AED use, and calling emergency medical care are critical to increase survival and recovery.
Sudden cardiac arrest can happen during exercise or at rest, or even during sleep. Some people are revived at first but may later die from brain damage caused by the brain not getting enough blood and oxygen for too long.
Signs and symptoms
These signs and symptoms of cardiac arrest are the same in children, youth, and adults:
- Collapse suddenly and lose consciousness (pass out).
- Are not breathing or are gasping for air.
- Don't respond to shouting or shaking.
- Don't have a pulse.
If you believe someone is having a sudden cardiac arrest, immediately call 911, begin cardiopulmonary resuscitation (CPR), and send someone to get an automated external defibrillator (AED) or get one yourself when safe to do so. Most AEDs are appropriate for use on adults and children over 8 years old. Continue giving CPR until medical professionals take over or the person begins breathing on their own.
Causes
Sudden cardiac arrest can be caused by many factors, including cardiomyopathy. When cardiomyopathy occurs, the normal muscle in the heart can thicken, stiffen, thin out, or fill with substances the body produces that do not belong in the heart muscle. It can affect people of any age, race, or sex, and often has no early symptoms.
In addition to cardiomyopathy, other causes of sudden cardiac arrest include heart defects or disorders a child is born with, infections of the heart, physical trauma, or structural heart diseases, among others.
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