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

Many people use the terms heart attack and cardiac arrest interchangeably, but these conditions aren’t the same.

A heart attack occurs when your heart doesn’t get enough blood flow. A cardiac arrest occurs when you experience a sudden collapse and loss of consciousness because your heart stops beating and can’t pump blood to supply oxygen to the rest of your organs. In many cases, a heart attack can raise your risk of developing cardiac arrest.123

Both heart attacks and cardiac arrest are life-threatening. While these conditions are related and can share similar symptoms, there are key differences.

Symptoms of a Heart Attack vs. Cardiac Arrest
Cardiac arrest and heart attacks both affect the heart, but each condition has different symptoms. A heart attack can often lead to cardiac arrest, so it’s important to recognize the symptoms of a heart attack and seek immediate medical care. Here’s a breakdown of how symptoms compare and contrast:14
National Heart, Lung, and Blood Institute. Cardiac Arrest Symptoms.

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Heart Attack Symptoms Cardiac Arrest Symptoms
Chest pain that radiates to the jaw, neck, or arm Sudden collapse
Shortness of breath Loss of consciousness
Fatigue Inability to breathe
Anxiety No detectable heartbeat
Heart palpitations Chest pain or shortness of breath before fainting
Nausea Lightheadedness prior to collapse
Differences
Heart attacks and cardiac arrest are both serious conditions that affect your heart and overall cardiovascular health. However, they do differ in causes, treatments, and overall outcomes.

Different Conditions Causes Heart Attacks and Cardiac Arrest
Heart attacks happen when the heart does not get enough blood flow. The coronary arteries are the blood vessels that bring blood, oxygen, and nutrients to the heart muscle. The heart muscle is continuously working, normally beating 60-100 times per minute, so it needs a constant blood supply to work properly.6

The leading cause of heart attacks is atherosclerosis, a buildup of cholesterol plaque in the coronary arteries. These plaques can rupture, forming a blood clot that either partially or completely blocks blood flow to the heart.1

On the other hand, several conditions can lead to cardiac arrest. A heart attack is one of the primary reasons someone might experience cardiac arrest, but these conditions can also cause your heart to stop beating:73

Arrhythmias (abnormal heart rhythms), such as ventricular fibrillation and ventricular tachycardia
Other heart conditions, like congenital heart defects and valvular heart disease
Hypoxia (low oxygen levels)
Hypothermia (low body temperature)
Low blood volume, such as with excess hemorrhaging (bleeding)
Excessively high or low potassium levels in the blood, with possibly severe magnesium and calcium imbalances
Hypoglycemia (low blood sugar)
Pulmonary embolism (blood clot in the lungs’ arteries)
Cardiac tamponade (fluid build-up around the heart)
Pneumothorax (collapsed lung)
Treatment Options Aren’t the Same
Both heart attack and cardiac arrest require emergency treatment. However, the specific treatment for each differs. The goal of treatment for a heart attack is to restore blood flow to the heart. This involves medications, such as blood thinners, and a procedure to restore blood flow. To treat a heart attack, a cardiologist (a doctor who specializes in the heart) typically performs a minimally invasive procedure called percutaneous coronary intervention (PCI) to open the blood flow in a coronary artery.8

Cardiac arrest requires immediate cardiopulmonary resuscitation (CPR) to prevent death. Anyone can perform CPR until help arrives. To perform CPR, press hard and fast on the center of a person’s chest about 100-120 times per minute. This helps keep blood flowing in the body.9

Send someone to get an automated external defibrillator (AED). This life-saving device can deliver an electric shock to restart the heart. Public buildings like train stations, airports, gyms, and office buildings often have an AED available to keep someone alive before paramedics arrive at the scene.9

Overall Outcomes Differ
Both heart attacks and cardiac arrest may be fatal, but their outcomes differ. Heart attacks are more common, with an estimated 805,000 occurring per year in the United States.1 While heart attacks carry a risk of death, not every heart attack is deadly. About 12% of heart attacks result in death within 30 days.10 An estimated 1 in 5 heart attacks is silent and goes unrecognized—and, as a result, are often left untreated.1

Cardiac arrest is always deadly without treatment. Without prompt CPR, people cannot survive a cardiac arrest. An estimated 60-80% of people who experience a cardiac arrest outside of the hospital succumb to their condition. That’s why giving CPR and using an AED as soon as possible is essential if you see someone who has gone into cardiac arrest.3

Similarities
While heart attacks and cardiac arrest have different causes, treatments, and outcomes, they do have some important similarities. Both are serious medical emergencies that affect the heart and require immediate care to prevent life-threatening complications.

Both Conditions Affect the Heart
Heart attacks and cardiac arrest involve the heart, the muscular organ responsible for pumping blood to the rest of the body’s organs and tissues. The heart relies on a complex electrical conduction system to generate a heartbeat. However, if a heart attack or cardiac arrest occurs, these conditions can affect the heart’s ability to pump blood effectively and cause dysfunction in the electrical system.2

During a heart attack, a blockage in the coronary artery prevents blood flow to the heart. This affects the heart’s pumping capability and can lead to arrhythmias (abnormal heart rhythms), which can increase the risk of cardiac arrest.11

Similarly, in cardiac arrest, your heart stops beating, which causes your heart to be unable to pump blood out to the body. Without proper functioning of the heart, your brain and vital organs can’t work normally, resulting in a sudden collapse.2

They Share Similar Preventative Strategies
Heart disease, including heart attack, is a major cause of cardiac arrest. For this reason, the preventive measures for both conditions are similar. To prevent both heart attack and cardiac arrest, it’s important to consider following these heart-healthy tips:122

Eat a diet high in fruits and vegetables and low in sodium
Engage in light to moderate physical exercise daily
Avoid or quit smoking
Sleep for at least seven hours per day
Get screened for conditions that can increase your risk of cardiovascular events, such as high blood pressure, high cholesterol, obesity, and type 2 diabetes
Both Require Immediate Care
When it comes to heart attack and cardiac arrest, time is of utmost importance to prevent life-threatening complications. The longer the heart muscle goes without blood during a heart attack, the more extensive the damage will be. Furthermore, there is a high risk of arrhythmias and cardiac arrest following a heart attack, so it’s best to seek healthcare promptly so you can receive treatment.13

Timing is also essential during a cardiac arrest. For every minute of delay in CPR, the probability of survival decreases dramatically. According to the American Heart Association, when witnesses of a cardiac arrest start CPR right away, chances of survival may double or triple. However, without CPR, cardiac arrest is often fatal.9