What Are Cardiac Arrest and Heart Attack?

Jan 4, 2023

4 min

Kirk Garratt, M.D., MSc

Fast Action Saves Lives.


When Buffalo Bills safety Damar Hamlin collapsed during an NFL game against the Cincinnati Bengals, it brought urgency to knowing signs of a cardiac arrest and what to do in case of a medical emergency involving the heart.


It’s a common misunderstanding that cardiac arrest and heart attack are the same. They are different, but both are very serious heart problems and require fast action to save lives.


"I think the very best bit of news for Mr. Hamlin is that the emergency medical technicians got to him very quickly." 


Heart attack and other conditions, including a rare type of trauma called commotio cordis, may disrupt the heart’s rhythm and lead to cardiac arrest. Commotio cordis can occur from a severe blow to the chest as in a sports injury.



What is cardiac arrest?

Cardiac arrest happens when the heart malfunctions and stops beating unexpectedly. Cardiac arrest is triggered by an electrical malfunction in the heart that causes an irregular heartbeat known as arrhythmia. The heart’s cardiac conduction system – or “electrical” system – is a specialized network of heart cells that keeps it beating regularly and effectively.


With the heart’s pumping action disrupted, it cannot pump blood to the brain, lungs or other organs.


Cardiac arrest often happens to people who didn’t know they had a heart problem.


Symptoms of cardiac arrest

Seconds after a cardiac arrest, a person becomes unresponsive, is not breathing or is only gasping. Death can occur within minutes if the victim does not receive treatment.



Causes of cardiac arrest

Cardiac arrest can run in families. People who have a family history of sudden cardiac death have a higher risk for sudden cardiac death.


Other health problems can increase the chance of a deadly heart rhythm including:

  • Heart disease (coronary artery disease).
  • A heart attack.
  • Heart failure.
  • Hypertrophic cardiomyopathy. This makes the heart thicker and larger than normal.


Blow to the chest that disrupts the heart rhythm as in commotio cordis.

Speak with your health care provider to learn if you have a health problem that raises your risk of cardiac arrest; treatment of that problem may help lower your risk. Medicine often can control the heart rhythm.


Helping someone having a cardiac arrest

Cardiac arrest can be reversible in some victims if treated within a few minutes. Health professionals, family or friends and even strangers may be able to help a person right away who has cardiac arrest.


  1. First, call 911 and start CPR right away. Click here for CPR basics, including videos.
  2. Then, if an Automated External Defibrillator (AED) is available, use it as soon as possible. AEDs are often available in airports, malls, and other public places. Click here for how to use an AED.
  3. If two people are available to help, one should begin CPR immediately while the other calls 911 and finds an AED.


In the ambulance and hospital, the person will receive emergency care. This care keeps the heart and lungs working to prevent damage to the body due to lack of oxygen. Doctors will try to find the cause of the cardiac arrest to prevent another one.


AEDs are portable, life-saving devices designed to treat people experiencing sudden cardiac arrest, a medical condition in which the heart stops beating suddenly and unexpectedly.


What is a heart attack?

A heart attack occurs when blood flow to the heart is blocked. A heart attack is a circulation problem with the heart.


A heart attack occurs when part of the heart muscle does not get enough blood and oxygen. This part of the heart starts to die.


Symptoms of a heart attack

The most common symptom of a heart attack is chest pain or pressure. Some people describe it as discomfort, squeezing, or heaviness in the chest. Other symptoms may be immediate and may include intense discomfort in the chest or other areas of the upper body, shortness of breath, cold sweats, nausea or vomiting.


Some people feel symptoms in other parts of their upper body such as:

  • Pain or discomfort in your back, jaw, throat, upper belly or arm.
  • Sweat, feeling sick to your stomach or vomiting.
  • Trouble breathing.
  • Feeling lightheaded or suddenly weak.
  • A racing or fluttering heartbeat.


More often, though, heart attack symptoms start slowly and persist for hours, days or weeks before a heart attack. Unlike with cardiac arrest, the heart usually does not stop beating during a heart attack. The longer the person goes without treatment, the greater the damage.


Heart attack symptoms in women can be different than men (shortness of breath, nausea/vomiting, and back or jaw pain).


Address heart attack symptoms immediately

Even if you’re not sure it’s a heart attack, call 911 if you have symptoms. Every minute matters. Emergency medical services staff can begin treatment when they arrive — up to an hour sooner than if someone gets to the hospital by car. These professionals also are trained to revive someone whose heart has stopped. Patients with chest pain who arrive by ambulance usually receive faster treatment at the hospital, too.


Click here for CPR training classes held by the American Heart Association in your area.



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Kirk Garratt, M.D., MSc

Kirk Garratt, M.D., MSc

Medical Director of Center for Heart & Vascular Health and John H. Ammon Chair of Cardiology

Dr. Garratt oversees one of the nation's busiest heart programs, renown for its exceptional speed in heart attack response times.

CardiologyCardiovascular DiseaseHeart Health

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