What is the definition of ventricular fibrillation (V-fib)?

Ventricular fibrillation (V-fib) is defined as an abnormal heart rhythm characterized by the rapid and uncoordinated quivering of the heart's ventricles. In this state, the ventricles do not effectively pump blood to the body, leading to a significant decrease in blood circulation. This lack of coordination prevents the heart from maintaining a regular heartbeat and can quickly lead to loss of consciousness and death if not treated immediately. The quivering motion means that the heart is not able to perform its function effectively, resulting in severe consequences for the individual.

The other options describe unrelated medical conditions or incorrect states of heart rhythms, such as rapid contractions or conditions unrelated to the heart itself. Therefore, option A accurately captures the essence of what V-fib entails, highlighting its critical nature in emergency medical situations.