Sudden Cardiac Arrest (SCA) vs Heart Attack

Sudden Cardiac Arrest (SCA), or Cardiac Arrest is the number one cause of death in the United States, accounting for more than 400,000 deaths each year. SCD is a catastrophe in which the heart abruptly and without warning ceases to function. It is particularly terrifying because it kills its victims within minutes and often occurs in outwardly healthy people who have no known heart disease.

No statistics are available for the exact number of cardiac arrests that occur each year. It’s estimated, however, that more than 95 percent of victims die before reaching the hospital.

The most common cause of SCA is a heart rhythm disorder (arrhythmia) called ventricular fibrillation (VF). VF is an “electrical problem” in the heart. Suddenly, the electrical signals that regulate the pumping action of the lower chambers of the heart (ventricles) become rapid and chaotic.

The normal rhythmic contractions of the ventricles stop, and the heart can’t pump blood to the rest of the body. The brain is starved of oxygen, and the individual loses consciousness in seconds.

In VF, muscle contractions in the lower chambers of the heart become chaotic, and can no longer pump blood to the body.

Without immediate emergency help, death follows within minutes of an episode of ventricular fibrillation. CPR and defibrillation must be commenced as soon as possible in order to improve chances of survival from a sudden cardiac arrest.

Sudden Cardiac Arrest is different to a Heart Attack!

Heart Attack, or myocardial infarction (MI), is a “plumbing problem” caused by clogged or blocked blood vessels that cut off the supply of blood to the heart.

SCA is NOT the same as a heart attack, or myocardial infarction (MI), which is caused by a sudden blockage of the blood supply to the heart.

SCA, or cardiac arrest, is a malfunction of the electrical system that coordinates the muscle contractions that pump blood through the body, and maintains the steady, rhythmic beat of the heart. It begins suddenly, triggered by electrical signals that become rapid and chaotic.

The lower chambers (ventricles) go into fibrillation – a rapid, and disorganized contraction of individual muscle fibers. The ventricles begin to spasm or quiver, and no longer are able to pump blood to the lungs, body, and brain. Death is inevitable within minutes without immediate emergency treatment.

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