Ventricular Fibrillation | Reference Guide.

EKG Features

Rate: Unmeasurable
Rhythm: Highly irregular
P Wave: Absent
PR Interval: Not measurable
QRS: None
Fibrillatory waves may be coarse or very fine. This is based upon their size. The longer V Fib occurs, the smaller the waveforms are likely to be.
Ventricular fibrillation is an abnormal, irregular heart rhythm with uncoordinated electrical activity and contractions. Because the ventricles are not contracting, blood is not circulating. Ventricular fibrillation is a medical emergency requiring immediate treatment.
External Source: http://www.nlm.nih.gov/medlineplus/ency/article/007200.htm
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