Cardiac Arrest

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Basics

• Summary
• Start Here
• Latest News
• Prevention and Risk Factors
• Treatments and Therapies

Learn More

• Related Issues
• Genetics

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• Health Check Tools

Research

• Clinical Trials
• Journal Articles

Resources

• Reference Desk
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• Teenagers
• Patient Handouts

Summary

The heart has an internal electrical system that controls the rhythm of the heartbeat. Problems can cause abnormal heart rhythms, called arrhythmias. There are many types of arrhythmia. During an arrhythmia, the heart can beat too fast, too slow, or it can stop beating. Sudden cardiac arrest (SCA) occurs when the heart develops an arrhythmia that causes it to stop beating. This is different than a heart attack, where the heart usually continues to beat but blood flow to the heart is blocked.

There are many possible causes of SCA. They include coronary heart disease, physical stress, and some inherited disorders. Sometimes there is no known cause for the SCA.

Without medical attention, the person will die within a few minutes. People are less likely to die if they have early defibrillation. Defibrillation sends an electric shock to restore the heart rhythm to normal. You should give cardiopulmonary resuscitation (CPR) to a person having SCA until defibrillation can be done.

If you have had an SCA, an implantable cardiac defibrillator (ICD) reduces the chance of dying from a second SCA.

NIH: National Heart, Lung, and Blood Institute

Start Here

• About Cardiac Arrest (American Heart Association)
• Sudden Cardiac Arrest (Texas Heart Institute) Also in Spanish
• Sudden Cardiac Arrest (SCA) (Heart Rhythm Society)
• What Is Sudden Cardiac Arrest? (National Heart, Lung, and Blood Institute)

Latest News

• How Devices in Public Places Can Restart Hearts (02/14/2027, Food and Drug Administration)

Prevention and Risk Factors

• Catheter Ablation (National Heart, Lung, and Blood Institute) Also in Spanish
• Understand Your Risk for Cardiac Arrest (American Heart Association)
• Warning Signs of Heart Attack, Stroke and Cardiac Arrest (American Heart Association)

Treatments and Therapies

• Automated External Defibrillator (National Heart, Lung, and Blood Institute)
• Automated External Defibrillators: Do You Need an AED? (Mayo Foundation for Medical Education and Research) Also in Spanish
• CPR: MedlinePlus Health Topic (National Library of Medicine) Also in Spanish

Related Issues

• Coronary Artery Anomalies (Texas Heart Institute) Also in Spanish
• Heart Attack or Sudden Cardiac Arrest: How Are They Different? (American Heart Association)
• Ventricular Fibrillation (Mayo Foundation for Medical Education and Research) Also in Spanish

Genetics

• Genetics Home Reference: progressive familial heart block (National Library of Medicine)

Health Check Tools

• Sudden Cardiac Arrest (SCA) Risk Assessment (Heart Rhythm Society)

Clinical Trials

• ClinicalTrials.gov: Death, Sudden, Cardiac (National Institutes of Health)
• ClinicalTrials.gov: Heart Arrest (National Institutes of Health)

Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)

• Article: Efficacy and safety of Shenfu injection for patients with return...
• Article: Associations between common ion channel single nucleotide polymorphisms and sudden...
• Article: Improved survival of hospitalized patients with cardiac arrest due to...
• Cardiac Arrest -- see more articles

Reference Desk

• Heart and Stroke Encyclopedia (American Heart Association)
• How the Heart Works (National Heart, Lung, and Blood Institute)

Find an Expert

• American Heart Association
• Find a course (American Heart Association)
• Heart Rhythm Society
• National Heart, Lung, and Blood Institute

Teenagers

• Sudden Death in Young People--Heart Problems Often Blamed (Mayo Foundation for Medical Education and Research) Also in Spanish

Patient Handouts

• Cardiac arrest (Medical Encyclopedia) Also in Spanish