What’s the difference between a heart attack, cardiac arrest, and heart failure? | 4 min read

A heart attack is often confused with cardiac arrest, and people often use these terms interchangeably, but they are not the same thing. A heart attack is when blood flow to the heart is blocked, and sudden cardiac arrest is when the heart malfunctions and suddenly stops beating. 

What is a heart attack?

Doctors refer to a heart attack as myocardial infarction when circulation is blocked or cut off and blood is no longer supplied to the heart muscle. A network of arteries surrounds the heart muscle and provides it with blood that is rich in oxygen. However, arteries can become clogged by a build-up of plaque on the inner walls, a condition known as arteriosclerosis. Plaque is formed when cholesterol combines with fat, calcium, and other substances in the blood. When one or more coronary arteries are completely blocked, it deprives the heart of the vital oxygen and nutrients needed to function appropriately, and a heart attack may occur. A heart attack is thus a “circulation” problem caused by a blockage in one or more of the heart’s arteries. 

If the blocked artery is not reopened quickly, the part of the heart normally nourished by the artery begins to die. The longer a person goes without treatment, the greater the damage. 

Symptoms of a heart attack may be immediate and intense, but more often, symptoms start slowly and persist for hours, days, or weeks before a heart attack:

• Chest pain or intense discomfort in the centre of the chest; also described as a heaviness, tightness, pressure, aching, burning, numbness, fullness, or squeezing feeling that lasts for more than a few minutes or goes away and comes back. It is sometimes mistakenly thought to be indigestion or heartburn.
• Pain or discomfort in other upper-body areas, including the arms, left shoulder, back, neck, jaw, or stomach.
• Difficulty breathing or shortness of breath.
• Sweating or “cold sweat.”
• Fullness, indigestion, or choking feeling (may feel like “heartburn”).
• Nausea or vomiting.
• Light-headedness, dizziness, extreme weakness, or anxiety.
• Rapid or irregular heartbeats.

Women may have shortness of breath, nausea, vomiting, back, neck, or jaw pain.

What is cardiac arrest?

A heart attack is caused by a blockage, while cardiac arrest occurs when the heart’s electrical system malfunctions. The heart gets out of rhythm, causing rapid and irregular heartbeats, which means your heart cannot pump effectively. As a result, the heart cannot pump blood to the brain, lungs, and other organs with its pumping action disrupted. If the electrical disturbance is significant, it can cause the heart to stop functioning altogether and sudden cardiac death. Cardiac arrest is an extreme emergency!

While there are warning signs for a heart attack, that is not the case with sudden cardiac arrest. Instead, the person will collapse with no pulse, no consciousness, and no breathing. 

Survival is possible after both a heart attack and sudden cardiac arrest. CPR (either via a defibrillator or chest compressions) is the first step in helping to save someone’s life while waiting for emergency personnel to arrive. Call an ambulance if you think someone is having a heart attack or collapses and isn’t breathing. The ambulance is equipped to treat cardiac arrest on the way to the emergency room.

What is heart failure? 

When your heart, which acts as a pump to push out blood through the arteries and circulatory system to the other organs and tissues, no longer works effectively, that’s heart failure or congestive heart failure.

High blood pressure, diabetes, obesity, and coronary artery disease (when a build-up of plaque in the arteries causes them to narrow and obstruct blood flow) are all conditions that lead to heart failure.

The Takeaway

It’s essential to focus on lifestyle changes to prevent heart attacks and heart failure. High cholesterol, high blood pressure, diabetes, lack of exercise, obesity, and cigarette smoking are major risk factors.

Genetic predisposition plays a role in your heart health, too. So even if you are otherwise healthy, if you have a family history of heart problems, you should discuss this with your general practitioner or cardiologist so you can be screened and monitored.