DEFIBRILLATION APPARATUS AND METHOD

摘要

An implanted defibrillator continuously monitors a patient's heart to detect the presence of fibrillation and repeatedly, automatically computes the approximate entropy of a series of data representing the fibrillating heart at a moment in time. The first approximate entropy score that meets a predetermined relation with respect to a predetermined threshold value activates an energy delivery system to defibrillate the heart with a low level shock. The process continues until defibrillation is successful. An external defibrillator incorporates the approximate entropy algorithm to achieve low level defibrillation. A method is disclosed which times the delivery of a defibrillating shock to a fibrillating heart to coincide with the moment that the defibrillation threshold is at a minimum.