Final answer:
Ventricular fibrillation prevents the heart muscle from contracting normally, leading to a wild and uncontrolled heartbeat. If left untreated, it can be life-threatening and may result in brain death. Defibrillation is the common treatment to restore a normal heart rhythm.
Step-by-step explanation:
Ventricular fibrillation prevents the heart muscle from contracting normally, which results in the heart beating in a wild and uncontrolled manner. This disrupts the heart's ability to effectively pump blood and can be a life-threatening condition. If left untreated for even a few minutes, ventricular fibrillation can lead to brain death. The most common treatment for ventricular fibrillation is defibrillation, which involves applying an electrical charge to the heart to restore a normal sinus rhythm.