Both heart attack and cardiac arrest are life-threatening medical events that must be treated as quickly and efficiently as possible to prevent loss of life. But what’s the difference between the two? What’s the right treatment in each case? Let’s take a look.

What’s the Difference Between a Heart Attack and Cardiac Arrest?

A heart attack occurs when a section of the heart does not receive oxygenated blood due to artery blockage. Unless the blockage is treated quickly, the affected part of the heart will die due to a lack of oxygen.

A heart attack may happen suddenly and without warning, but more commonly, the symptoms accumulate over time.

Cardiac arrest occurs when the heart’s electrical system fails to work properly, causing an irregular heartbeat, or arrhythmia. Once this happens, the heart can’t pump blood, and blood flow to the organs, including the brain and lungs, is cut off. Without urgent treatment, this leads to loss of consciousness, no pulse, and soon after, death.

In other words, a heart attack is caused by a circulation issue, while cardiac arrest is a result of problems with the heart’s electrical system.

The risk of cardiac arrest does increase sharply after a heart attack or during recovery from one, but most heart attacks are not followed by cardiac arrest. However, cardiac arrest is also more likely to occur with heart conditions such as heart failure, cardiomyopathy, and ventricular fibrillation.

How to Recognize and Respond to a Heart Attack

The most common symptom of a heart attack is chest pressure or pain that may also radiate toward the back, shoulders, neck, jaw, or arms. Other characteristic signs include dizziness, a faint feeling, shortness of breath, sweating, and nausea.

Symptoms of a heart attack may differ between men and women. In particular, women are more likely to feel symptoms other than chest pain, such as shortness of breath and nausea or vomiting.

If you suspect you or someone near you is having a heart attack, call your local emergency number. If you feel the onset of heart attack symptoms, don’t attempt to drive to a hospital yourself unless you have absolutely no choice.

Chew and swallow an aspirin and take nitroglycerin if prescribed.

If you are near an unconscious person and have received CPR (cardiopulmonary resuscitation) training, the emergency dispatcher may advise you to start CPR. Otherwise, you may be advised to perform chest compressions.

If you have access to an automated external defibrillator (AED), you may use it while closely following instructions.

How to Recognize and Respond to Cardiac Arrest

Cardiac arrest ultimately results in a sudden loss of consciousness and an inability to breathe. However, there can be symptoms before this occurs, such as shortness of breath, heart palpitations, sudden weakness, or chest pains. As these symptoms closely resemble a heart attack, it can be difficult to tell the two apart.

One of the key differences is that cardiac arrest occurs quickly, and after falling unconscious, the afflicted person will flatline, known as asystole (a straight line showing on an ECG), meaning there is no movement or electrical activity in the heart—a state that will quickly lead to death if resuscitation is not successful. During a heart attack, there is usually still a heartbeat.

If you think a person near you is suffering from cardiac arrest, dial your local emergency response number immediately and use an AED if one is available.

If the person is already unconscious and not breathing, start CPR, pushing down at least two inches at a rate of 100 to 120 pushes per minute in the center of the chest. Continue administering CPR until the afflicted person starts breathing and responding, or until an EMS team arrives on the scene and takes over.

Final Thoughts

Over 320,000 cardiac arrest cases occur outside of hospitals every year in the United States, making it a leading cause of death. Promptly performed CPR can sharply increase a victim’s chance of surviving this cardiovascular event. That’s why life support certifications are so crucial for medical personnel working in settings such as emergency rooms and cardiac care units.

Life support certifications are short training courses that can be classified as BLS (Basic Life Support), ACLS (Advanced Cardiac Life Support), and PALS (Pediatric Advanced Life Support).

A BLS course offers a variety of techniques such as chest compressions, rescue breathing, use of AEDs, and other basic skills that can save a patient’s life in emergency conditions. An ACLS course is more advanced and includes clinical interventions for cardiovascular emergencies. A PALS course is targeted at medical professionals working with infants and children.

Life support certifications are useful not only in a medical setting, but can also help save the life of a friend, a family member, or any random person suffering from an acute, life-threatening medical emergency. While they are good to have in certain fields, such as those involving children or the elderly, the value of a BLS or ACLS certification is incalculable for medical professionals who have dedicated their careers to saving people’s lives.

Cite this article as:
Editorial Staff, "Cardiac Arrest vs. Heart Attack – How to Respond to These Emergencies," in Medicalopedia, June 29, 2020, [Permalink: https://www.medicalopedia.org/9012/cardiac-arrest-vs-heart-attack-how-to-respond-to-these-emergencies/].