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Sudden Cardiac Death in Athletes


The Manual's Editorial Staff

Last full review/revision May 2020| Content last modified May 2020
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Sudden cardiac death is when someone dies suddenly from a heart problem. Sudden cardiac death in athletes is when someone dies suddenly from a heart problem brought on by exercise.

  • Sudden cardiac death in athletes is rare (about 1 in 200,000 athletes)

  • It can happen to older people who know they have heart problems

  • It also can happen to people who are young and seem healthy but have a heart problem they don't know about

  • Talk to your doctor before starting a new sport or exercise routine

People also can die during exercise because of things like an asthma attack, heatstroke, or an injury. These aren't usually considered sudden cardiac death because a heart problem wasn't the main cause.

What causes sudden cardiac death in athletes?

Older people usually have coronary artery disease. The arteries that feed their heart with oxygen are clogged. They may or may not know they have a heart problem.

Younger people usually have rare heart problems that they were born with. They usually don't know they have a heart problem.

The most common heart problem in younger people is:

Other heart problems in younger people include:

  • Heart conditions that make your heart rhythm abnormal when you exercise or feel stress, such as long QT syndrome

  • A defective heart valve (aortic stenosis)

  • A weak area or bulge in a part of your aorta (the main artery that carries blood away from your heart to the rest of your body—the weak area or bulge is called an aortic aneurysm)

  • Birth defects in your coronary arteries (blood vessels that bring your heart oxygen)

At any age, you're more likely to have sudden cardiac death during exercise if you use street drugs that stimulate the heart. Such drugs include cocaine and amphetamines.

What are the symptoms of sudden cardiac death?

Most young athletes are healthy and don't know they have a heart problem. Some athletes have warning signs such as fainting or shortness of breath. Athletes may not realize these are symptoms of a serious problem and may not tell anyone.

However, the first sign is usually that the person suddenly collapses. Their heart isn't beating, and they aren't breathing. People usually die unless given CPR.

How can doctors tell if I am at risk for sudden cardiac death?

See your doctor before you begin a sport or exercise program. Your doctor will ask about your health history and do a physical exam to catch problems that could make exercise dangerous for you.

High school athletes should have an examination every other year. Adults should have one every 4 years. If doctors know you have certain medical problems, they'll usually check you more often.

Risk factors doctors will ask you about include:

  • Having symptoms such as chest pain or discomfort, a fast beating heart or a heartbeat that feels uneven, fainting or near-fainting, fatigue, and difficulty breathing, especially when these symptoms happen during hard exercise

  • Having family members who fainted or died during exercise, or who died suddenly before about age 50

  • Using drugs

Depending on your age, health history, symptoms, and the specific sport you do, doctors may do tests such as:

  • Electrocardiogram (ECG—a quick, painless, harmless test that measures your heart’s electrical currents and records them on a piece of paper)

  • Ultrasound (a test that uses sound waves to create a picture of your heart and how it's working)

  • Stress test (a test to check how your heart works when it’s beating faster, like when you’re working out)

In some countries outside the United States, doctors recommend that everybody get an ECG before starting an exercise program.

How do doctors treat sudden cardiac death?

A person who stops breathing and collapses needs immediate treatment:

  • CPR (a life-saving method of pressing on the chest and giving rescue breathing)

  • Use of an external defibrillator (a device that delivers an electrical shock to the chest to bring back a regular heartbeat)

If the person lives, doctors treat the condition that caused the problem. They may give medicines or put in an implantable cardioverter-defibrillator. An implantable cardioverter-debrillator is a device doctors put in the heart to monitor its beat and restart the heart if it stops working.

Automated External Defibrillator: Jump-Starting the Heart

An automated external defibrillator (AED) is a device that can detect and correct a type of abnormal heart rhythm called ventricular fibrillation. Ventricular fibrillation causes cardiac arrest.

If cardiac arrest occurs, an AED, if available, should be used immediately.

Automated External Defibrillator: Jump-Starting the Heart
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