Ventricular fibrillation

Alternative Names

VF; Fibrillation - ventricular

Definition

Ventricular fibrillation (VF) is a severely abnormal heart rhythm (arrhythmia) that causes death unless immediately treated. VF is responsible for 75 - 85% of sudden deaths in persons with heart problems.

Causes

To pump blood out to the body, all areas of the heart normally squeeze (contract) at the same time. The heart’s upper chambers (the atria) contract before the heart’s bottom two chambers (ventricles). During VF, however, the contractions become disorganized.

The most common cause of VF is a heart attack, but 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)

While most people suffering from VF have no previous history of heart disease, many have risk factors for cardiovascular disease, such as smoking, hypertension, and diabetes.

References

Bernard SA, Gray TW, Buist MD: Treatment of Comatose Survivors of Out-of-Hospital Cardiac Arrest with Induced Hypothermia. N Engl J Med. 2002; 346(8): 557-63

Healey JS, Hallstrom AP, Kuck KH, et al. Role of the implantable defibrillator among elderly patients with a history of life-threatening ventricular arrhythmias. Eur Heart J. 2007 Feb 5; [Epub ahead of print].

Fish FA. Ventricular fibrillation: basic concepts. Pediatr Clin North Am. Oct 2004; 51(5): 1211-21.

Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed. St. Louis, Mo; WB Saunders; 2005:852-853.