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Cardiac arrest

Cardiac arrest

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Cardiac arrest is an abrupt loss of heart function due to a disruption in the normal electrical impulses that control the heart rate and rhythm. It is a medical emergency and can be fatal if not treated immediately. Cardiac arrest is not the same as a heart attack, although a heart attack can lead to cardiac arrest.

When cardiac arrest occurs, the heart stops beating effectively and stops pumping blood to the brain and other organs. As a result, the brain and other organs can be damaged or destroyed without oxygen-rich blood.

Various conditions, including heart attack, electrocution, drowning, drug overdose, and respiratory arrest, can cause cardiac arrest. However, the most common cause of cardiac arrest is an arrhythmia called ventricular fibrillation. This is an abnormal heart rhythm in which the heart beats rapidly and irregularly, causing the heart to quiver rather than pump blood. Ventricular fibrillation is often caused by a heart attack, but can also be caused by an electrical shock, an overdose of certain drugs, or an electrolyte imbalance.

Treatment for cardiac arrest involves restoring the heart’s normal rhythm. This is usually done with a defibrillator, which delivers an electric shock to the heart to restore normal rhythm. Other treatments may include cardiopulmonary resuscitation (CPR), medications, and other interventions to restore blood flow to the brain and other organs.

If cardiac arrest is treated quickly and effectively, it can restore normal heart rhythm and blood flow. However, if treatment is delayed or ineffective, the patient may suffer permanent brain damage or death.

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  • American Heart Association. (2021). Cardiac Arrest. Retrieved from
  • Mayo Clinic. (2021). Cardiac Arrest. Retrieved from