Sudden Cardiac Arrest

Sudden Cardiac Arrest (SCA) occurs when the electrical system to the heart malfunctions and suddenly becomes very irregular. The heart beats dangerously fast. The ventricles may flutter or quiver causing ventricular fibrillation (VF), and subsequently the ventricles of the heart cannot carry out their normal function of pumping blood around the body. The person will lose consciousness immediately. Emergency treatment includes cardiopulmonary resuscitation (CPR) and defibrillation. CPR keeps enough oxygen in the lungs and gets it to the brain until the normal heart rhythm is restored with a therapeutic electric shock to the chest (defibrillation). Without the intervention of Cardiopulmonary Resuscitation (CPR) and defibrillation being administered death can occur within minutes. An SCA can happen to anyone regardless of age and fitness level.

A cardiac arrest may be triggered by a heart attack. A heart attack is when one of the coronary arteries becomes blocked. The heart muscle is deprived of its vital blood supply and, if left untreated, will begin to die because it is not getting enough oxygen. Many cardiac arrests in adults happen because of a heart attack. This is because a person who is having a heart attack may develop a dangerous heart rhythm, which in turn can cause a cardiac arrest. Most heart attacks do not lead to sudden cardiac arrest. But when sudden cardiac arrest occurs, heart attack is a common cause.

Other causes of cardiac arrest include:
Blunt blows to the chest (Commotio cordis)
Heart disease/conditions (causing cardiac arrhythmia)
Respiratory arrest
Electrocution
Choking
Traumatic accident