Heart Attack vs. Sudden Cardiac Arrest: What’s the Difference?
The terms “sudden cardiac arrest” and “heart attack” are often used as if they’re the same. Here’s how these two life-threatening heart conditions differ.
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Many people use the terms “sudden cardiac arrest” and “heart attack” interchangeably. But they are not the same.
Sudden cardiac arrest occurs when the electrical system to the heart malfunctions and suddenly becomes very irregular, causing the heart to beat dangerously fast.
“The lower chambers of the heart that are supposed to pump blood to the rest of the body, because of an unexpected and sudden onset of electrical disturbances, make the heart muscle quiver. The rhythm is ventricular fibrillation or ventricular tachycardia. The heart quiver doesn’t pump blood to the brain or the rest of the body, which causes a person to collapse,” Dr. Saliba says. “Death follows unless emergency treatment is begun immediately.”
A heart attack occurs when there is a sudden blockage in one or more coronary arteries. These are the vessels that feed the heart muscle with blood supply. A blockage prevents the heart from receiving enough oxygen-rich blood and damages the heart muscle.
“A heart attack is more like a plumbing problem,” Dr. Saliba says. A heart attack may result in a sudden death episode as the oxygen deprived heart muscle may exhibit electrical disturbances that result in ventricular arrhythmia and sudden collapse.
Acting quickly — starting with calling 911 — is essential whether someone has had a sudden cardiac arrest or heart attack.
If you see someone collapse, it doesn’t matter which one it is — you need to start cardiopulmonary resuscitation (CPR) right away and have someone get the closest automatic external defibrillator (AED) if one is available, Dr. Saliba says.
CPR helps to get enough blood to the brain until the normal heart rhythm is restored with an electric shock to the chest (defibrillation). Portable defibrillators used by emergency personnel or public access defibrillators may help save the person’s life.
“More people are now aware of how to use AEDs because every minute that passes without resuscitation decreases by at least 10 percent the chances of the patient making it through,” Dr. Saliba says.
Many factors can increase a person’s risk of sudden cardiac arrest. The most significant one is coronary artery disease, especially in people with a recent history of heart attack.
The best way to decrease your chances of a cardiac arrest or heart attack is to control risk factors, including lowering high blood pressure, controlling diabetes and stopping smoking, Dr. Saliba says.