Sudden Cardiac Arrest
What is sudden cardiac arrest?
Sudden cardiac arrest occurs when the heart's electrical system malfunctions. It is not a heart attack! A heart attack is when a blockage in a blood vessel interrupts the flow of oxygen-rich blood to the heart causing the death of the heart muscle.
SCA occurs when there is an electrical problem, and a heart attack occurs when there is a circulation problem.
The most common cause of cardiac arrest is a heart rhythm disorder or arrhythmia called ventricular fibrillation (VF). The heart has a natural pacemaker, which triggers each heartbeat sending electrical impulses along various pathways in the heart, causing a contraction in normal sinus rhythm. When the contraction occurs, blood flows throughout the body.
However, in ventricular fibrillation, the electric signals controlling the heart because rapid and chaotic. Due to this, the lower chambers of the heart, the ventricles, quiver, or fibrillate instead of contracting, and they no longer pump blood throughout the body. When blood stops flowing normally, the brain becomes starved for oxygen, and the person loses consciousness in seconds. Unless the victim receives an emergency shock delivered to the heart using an automated external defibrillator (AED), death will occur within minutes. More than 70% of ventricular fibrillation victims die before ever reaching the hospital.