Ventricular fibrillation

A life-threatening heart rhythm disorder where the lower chambers quiver (frequency of >300-500 beats per minute) instead of pumping, causing cardiac arrest and sudden death unless treated immediately.

Common causes:

• Myocardial infarction

• Ischemia

• Cardiomyopathy

• Electrolyte imbalance: Dangerously low or high potassium or magnesium

• Electrical trauma: Severe electric shock or lightning strike

• Substance misuse: Stimulants like cocaine or methamphetamine