EKG

Ventricular Fibrillation:

Random electrical activity with no recognizable QRS complexes

Premature Ventricular Contraction:

Ectopic ventricular pacemaker inserts an ectopic beat = wide and bizarre QRS complex before the next sinus beat occurs

Ventricular Tachycardia:

Wide and bizarre but recognizable QRS complexes occur at an accelerated rate