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Sudden Cardiac Arrest vs. Heart Attack

Do you know if a sudden cardiac arrest (SCA) and a heart attack are the same medical emergency with two different names? Not at all, see the chart below to learn the differences.

  Sudden Cardiac Arrest (SCA)
 Heart Attack
SCA is a chaotic electrical condition of the heart resulting in the loss of blood flow to the brain and body. The most common form of SCA is ventricular fibrillation. The medical term for a heart attack is myocardial infarction: a blockage of the coronary arteries leading to a decrease in blood flow. When this happens, the heart muscles die or become permanently damaged.
Causes Electrical impulses of the heart become chaotic due to a blow to the chest or other (sometimes-unknown) health-related issues. As a result, the heart stops beating regularly and begins to flutter rapidly. Plaque made of cholesterol and other cells builds up in the walls of the heart’s arteries. When the buildup is great enough, the plaque creates a blockage, known as an occlusion, which restricts the blood supply to the heart muscle.
Symptoms Typically, there are no symptoms to SCA. Usually, the first indication of SCA is when the victim faints. The second sign is breathing cessation. Warning signs of heart attack include a tightening feeling in the chest, a sore or numb left arm, lower back, neck, and/or jaw. Other signs include bad indigestion, a feeling that something heavy is sitting on your chest, and shortness of breath.
Victim's Response
A sudden cardiac arrest victim always loses consciousness from lack of oxygen. The victim of a heart attack is usually conscious and alert.
Risk of Death
A victim of SCA will die unless treated. If left untreated, the chances of survival decrease by 10% per minute. Typically, permanent brain damage occurs within 5-7 minutes. Most victims can recover fully and lead normal lives, but about a third of heart attacks are deadly. A heart attack can lead to sudden cardiac arrest.
Treatment The only treatment for SCA is defibrillation from an automated external defibrillator (AED). A shock from the AED stops the chaotic electrical activity and allows the heart's sinus node to resume a normal electrical impulse. One treatment of a heart attack can be angioplasty, which opens up the blocked vessels with a medical balloon. Afterwards, a stent can be placed in the artery to help keep it open. Other treatments include clot-busting drugs called thrombolytics or nitroglycerin to reduce chest pain.