Ventricular Fibrillation

Ventricular fibrillation (VF) is a dangerous, potentially life-threatening heart rhythm problem. This type of arrhythmia can cause the heart to stop beating abruptly (cardiac arrest) and lead to death within minutes.

Normal electrical impulses

The heart's internal electrical system sends impulses through the heart that control heartbeat, the rhythmical pumping of blood to all vital organs. Abnormal heart rhythms can interfere with this process. Arrhythmias may make the heart to beat too fast, too slow, or in a disordered manner.

VF is an arrhythmia that triggers the lower chambers of the heart to twitch and quiver. They contract in an unsynchronized way and pump little or no blood from the heart.


Heart attack is the most common cause of VF. Other conditions can also trigger this type of arrhythmia. They include: 

  • Diseases of the heart muscle

  • Congenital heart conditions

  • Heart surgery

  • Electrocution

  • Injury to the heart

  • Lack of oxygen to the heart


Many people who experience VF have no previous history of heart problems. They may, however, be at higher risk for cardiovascular disease because of tobacco use, diabetes, and/or high blood pressure.


People who suffer VF may experience chest pain, rapid heartbeat, nausea, shortness of breath, and/or dizziness up to an hour before they collapse. Those who experience cardiac arrest stop breathing, are unresponsive, and have no pulse or blood pressure.


VF is a medical emergency. Victims need an electrical shock from an external defibrillator within minutes to restore normal heart rhythm. Many public places have automated external defibrillators (AEDs) for emergency use.

Doctors may also prescribe medications that can help improve heart function and heartbeat. Those who suffer significant damage to the heart muscle may need to have an implantable cardioverter defibrillator or a procedure such as balloon angioplasty or bypass surgery, depending on the cause of VF.

Victims who remain in a coma after treatment may have a better recovery if they have moderate hypothermia therapy to keep their body temperature slightly below normal for several hours. 

Those who survive VF and are at risk for future events could benefit from an implantable cardioverter defibrillator, which shocks the heart back into a normal rhythm when necessary.


Taking a course in cardiopulmonary resuscitation is a good way for family members and friends to be proactive about helping VF survivors or loved ones with heart disease. They may also want to consider purchasing an AED for personal use, although debate continues over the benefits of in-home AEDs.


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