Currently left ventricular ejection fraction is the only widely used parameter for prediction of sudden cardiac arrest manifesting as ventricular fibrillation or pulseless ventricular tachycardia. These are also known as shockable rhythms as they are amenable to revival with a direct current shock, unlike asystole and pulseless electrical activity.
It has been shown that ventricular fibrillation constitutes 93% of shockable rhythms while pulseless VT contributes only 7%. A new clinical algorithm called VFRisk has been derived by Chugh SS et all using machine learning and artificial intelligence techniques using a large community database of about 1 million persons.
