Final answer:
Ventricular fibrillation is an emergency condition that leads to erratic heartbeats and causes 90% of cardiac arrest cases. Treatment usually involves defibrillation with special paddles or external automated defibrillators.
Step-by-step explanation:
Ventricular fibrillation is a medical emergency that can cause cardiac arrest, where the heart beats irregularly and ineffectively. Specifically, it is characterized by the heart's ventricles beating erratically, which prevents the heart from pumping blood effectively. This condition is a leading cause of cardiac arrest and can lead to brain death if not treated within minutes. The most common treatment for ventricular fibrillation is defibrillation, which delivers an electrical shock to the heart using special paddles or external automated defibrillators (EADs) to reestablish normal sinus rhythm. Ventricular fibrillation causes a significant number of cardiac arrest cases.
In response to the student's question, Ventricular fibrillation causes 90% of cases of cardiac arrest.