Lifesaving Facts About Sudden Cardiac Arrest

03/29/2021 | 5 min. read

Dr. Stephen Sinatra

Dr. Stephen Sinatra

When you hear about someone dying of heart disease, the usual assumption is that person had a heart attack. Yet, half of all heart disease deaths—about 325,000 per year—are caused by something altogether different: sudden cardiac arrest. 

If this is news to you, you aren’t alone. A 2017 survey found that awareness of sudden cardiac arrest is extremely low. Only 18% of survey respondents were familiar with it. 

This needs to change, because if cardiac arrest is not recognized and treated immediately—before an ambulance arrives—death is inevitable.

What Is Sudden Cardiac Arrest?

Much of the lack of awareness is confusion about sudden cardiac arrest vs. heart attack. Simply put, a heart attack is a plumbing problem while cardiac arrest is an electrical malfunction. 

A heart attack is caused by coronary artery disease, or a buildup of plaque in the “pipes”—the arteries that supply the heart. As the disease progresses, the arteries become narrower, which restricts blood flow to the heart muscle. A heart attack occurs when a coronary artery is completely blocked, usually by a blood clot, and the heart is deprived of blood and oxygen. 

Cardiac arrest, on the other hand, is due to a glitch in the heart’s electrical system that triggers abnormally fast or irregular heart rhythms (arrhythmias). The most common cause of sudden cardiac arrest is ventricular fibrillation. The ventricles—the large lower chambers of the heart that move blood through the body—quiver or flutter rather than beating normally, and the heart is unable to pump blood to the brain and other organs.

Heart attacks are bad news because they damage the cardiac muscle and may have lasting effects, but many people survive heart attacks. Chest pain and other symptoms often cue you in that something is wrong. The heart doesn’t stop beating, and there is usually time to get medical attention. 

With cardiac arrest, all bets are off. When the heart is unable to deliver blood and oxygen to the brain, loss of consciousness occurs within seconds and brain death within minutes. It happens so fast—and often with few warning signs—that only a small percentage of people who experience a cardiac arrest outside a hospital get treated in time. 

Who Is at Risk?

Sudden cardiac arrest seems to strike at random and out of the blue, but in almost all cases there is an underlying cardiovascular disorder. It may not have been previously diagnosed, but it’s there. 

About 80% of victims have coronary artery disease, and most of them had a previous heart attack that damaged the heart. Often it was fairly recent—the risk of going into cardiac arrest is particularly high immediately following a heart attack and during recovery. 

Other cardiovascular conditions that increase risk include heart failure, cardiomyopathy, and a history of ventricular arrhythmias. There are also links between atrial fibrillation and sudden cardiac death, although the risk is most significant in patients who also have other heart problems in addition to atrial fibrillation. In children and adolescents, congenital heart defects or inherited cardiovascular conditions are prominent causes of sudden cardiac death. Fortunately, these tragedies are blessedly rare. 

In the past few years, there has been an increase in sudden cardiac arrests in young adults, especially younger African Americans. Nevertheless, cardiac arrest is most common in people who are middle-aged or older, as they are more likely to have underlying heart disease.

Protect Yourself

The best way to protect yourself is by adopting a healthy lifestyle and managing the usual cardiovascular risk factors:

You also need to pay attention to subtle warning signs. Sudden cardiac arrest isn’t always 100% sudden. About half of patients experience palpitations, dizziness, shortness of breath, or other symptoms in the weeks or minutes prior to their cardiac arrest. Don’t ignore them.

If you have survived a cardiac arrest, your doctor may recommend antiarrhythmic drugs or an implantable cardioverter defibrillator, which detects dangerous arrhythmias and shocks the heart back into normal rate and rhythm. They may be necessary, but I strongly suggest getting a second opinion before agreeing to either.   

Protect Others by Learning Hands-Only CPR 

The only real treatment for sudden cardiac arrest is to restore normal heart rhythm. That’s why everyone—and I mean everyone—should learn how to do CPR. It keeps the victim alive by moving blood through the body and brain until a defibrillator or medical professional can get the heart beating again. 

If someone suddenly collapses or is unresponsive and isn’t breathing, call 911 and immediately begin CPR. About 70% of cardiac arrests happen at home, but if you’re in a mall, airport, church, gym, etc., ask another bystander to find an automated external defibrillator (AED), which most public places have. 

Do not stop CRP until a defibrillator or emergency medical crew arrives. The only chance the victim has of making it is to keep blood and oxygen circulating.  

You don’t have to do mouth-to-mouth if you don’t know how or are uncomfortable with it. Hands-only CPR can also save lives. Simply push the center of the chest down hard and fast at a rate of 100–120 pushes a minute. A good way to get the proper rhythm is to time your compressions to the beat of the Bee-Gees’ song “Stayin’ Alive” from the movie Saturday Night Live. (It’s one of those songs that’s hard to forget.) 

According to the American Heart Association, immediate bystander CPR doubles to triples the odds of survival and recovery after sudden cardiac arrest. Sadly, only about third of those who have a cardiac arrest outside a hospital get CPR. As a result, survival rates are very low. 

I encourage everyone to take a CPR class or at least watch a video; the Red Cross offers both. Spread the word! The life saved may be a loved one’s—or your own. 

Dr. Stephen Sinatra

Meet Dr. Stephen Sinatra

Dr. Stephen Sinatra is a highly respected and sought-after cardiologist and nutritionist with more than 30 years of clinical practice, research, and study. His integrative approach to heart health focuses on reducing inflammation in the body and maximizing the heart's ability to produce and use energy.

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