Which description best matches ventricular fibrillation?

• A. Chaotic heart rhythm without a pulse, shockable
• B. Slow rhythm with a pulse
• C. Chaotic heart rhythm with a pulse
• D. Regular rhythm with a pulse

Answer: (C)

Ventricular fibrillation is caused by chaotic, uncoordinated electrical activity in the ventricles, so the ventricles quiver rather than contract as a unit. This prevents effective cardiac output, leading to no detectable pulse. Because it is an irregular, disorganized rhythm that prevents proper pumping, it is one of the primary shockable rhythms in emergency care.

Therefore, the description that best matches ventricular fibrillation is a chaotic heart rhythm without a pulse. The other descriptions describe rhythms with a pulse or with regular or slow patterns, which do not fit VF. In real clinical practice, a chaotic rhythm with a pulse would be unusual for VF, since pulselessness is a hallmark of this condition. The key takeaway is that VF is chaotic and pulseless and requires rapid defibrillation.