Ventricular fibrillation (VF) is a severely abnormal heart rhythm (arrhythmia) that can be life-threatening.
Overview, Causes, & Risk Factors
The heart pumps blood to the lungs, brain, and other organs. Interruption of the heartbeat for only a few seconds can lead to fainting (syncope) or cardiac arrest.
Fibrillation is an uncontrolled twitching or quivering of muscle fibers (fibrils). When it occurs in the lower chambers of the heart, it is called ventricular fibrillation. During ventricular fibrillation, blood is not removed from the heart. Sudden cardiac death results.
The most common cause of VF is a heart attack. However, VF can occur whenever the heart does not get enough oxygen or if a person has other heart disorders.
Conditions that can lead to VF include:
- Congenital heart disease
- Electrocution accidents or injury to the heart
- Heart attack
- Heart muscle disease, including cardiomyopathies
- Heart surgery
- Ischemia (lack of oxygen to the heart muscle because of narrowed coronary arteries or shock)
- Sudden cardiac death (commotio cordis), typically occurring in athletes after a trauma over the surface of the heart
Most people with VF have no history of heart disease. However, many have risk factors for cardiovascular disease, such as smoking, high blood pressure, and diabetes.
Pictures & Images
Heart, section through the middle
The interior of the heart is composed of valves, chambers, and associated vessels.
Heart, front view
The external structures of the heart include the ventricles, atria, arteries and veins. Arteries carry blood away from the heart while veins carry blood into the heart. The vessels colored blue indicate the transport of blood with relatively low content of oxygen and high content of carbon dioxide. The vessels colored red indicate the transport of blood with relatively high content of oxygen and low content of carbon dioxide.
Review Date : 5/15/2008
Reviewed By : Alan Berger, MD, Assistant Professor, Divisions of Cardiology and Epidemiology, University of Minnesota, Minneapolis, MN. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.