The Defib AED Literature is generally used to resuscitate people who have had a sudden cardiac arrest. This generally happens when the electrical activity of the heart is disrupted, resulting in a dangerously rapid heartbeat or a fast and irregular pulse. If the patient is suffering ventricular fibrillation or ventricular tachycardia and there is an Defib AED Literature nearby, a bystander or a family member can use it to shock the heart back to normal rhythm and perhaps save their life.