Ventricular fibrillation

A life-threatening cardiac arrhythmia in which the ventricles quiver chaotically at very high frequencies (>300-500 beats/minute) instead of contracting effectively, resulting in loss of cardiac output, cardiac arrest, and sudden death unless treated immediately.

Causes

• Myocardial infarction

• Myocardial ischemia

• Electrical cardiac disorder: 

  • Long QT syndrome

  • Brugada syndrome

• Cardiomyopathy

• Heart failure

• Electrolyte abnormalities

  • Hypokalemia

  • Hyperkalemia

  • Hypomagnesemia

  • Hypermagnesemia

• Electric shock (lightning strike)

• Drug and toxins

  • Cocaine

  • Methamphetamine

  • Other stimulant toxicity

  • Certain proarrhythmic medications