Ventricular Fibrillation
This is a condition in which the electrical Impulses generated within the heart become chaotic, this results in loss of co-ordination in the contraction of the various chambers of the heart.
This means that the heart cannot pump blood around the body and therefore the vital organs, most importantly the brain, become starved of oxygen
V.F is said to be Refractory when it does not respond to defibrillation.