Transcript Ventricular_Fibrillation

Ventricular Fibrillation
Ventricular fibrillation occurs when parts of the ventricles depolarize repeatedly in an erratic,
uncoordinated manner. The EKG in ventricular fibrillation shows random, apparently
unrelated waves. Usually, there is no recognizable QRS complex.
Normal Sinus
VF
Ventricular fibrillation is almost invariably fatal because the uncoordinated contractions of ventricular
myocardium result in ineffective pumping and little or no blood flow to the body. There is lack of a pulse
and pulse pressure and the patients lose unconsciousness rapidly. When the patient has no pulse and
respiration the patient is said to be in cardiac arrest. A person in cardiac arrest must receive CPR
immediately.
Electrical defibrillation, by passage of current at high voltage, may be successful in restoration of a
normal regular rhythm. The electrical current stimulates each myocardial cell to depolarize
simultaneously. Following synchronous repolarization of all ventricular cells, the SA node assumes
the role of pacemaker and the ventricular myocardial cells can resume the essentially simultaneous
depolarization of normal sinus rhythm.
Ventricular fibrillation is associated with drug toxicity, electrocution, drowning and myocardial
infarction.