Question: What is the difference between a defibrillator used in the emergency room and a defibrillator that is surgically implanted in a patient?
Answer: Well, the defibrillator that is used in the emergency room, or by the paramedics, or an automatic external defibrillator are used for trans-thoracic or trans-chest shock. One lead is placed here, another lead is placed here -- so the current goes through the heart to defibrillate someone who has cardiac arrest.
An implanted defibrillator is very much like a pacemaker, except it's a little larger. It's referred to as a pacemaker plus. And what it does is monitors the patient's rhythm, and if they fibrillate, shocks them right back into regular rhythm.