Patent ID: 6324421
Filing Date: 2001-11-27
Classification: A61B,A61N,Y10S

Abstract:
A method for determining whether there has been an axis shift in an electrocardiogram waveform comprising a repeated cycle of steps, each cycle comprising the steps:a) for a given cardiac cycle, collecting into a buffer selected characteristic portions of the electrocardiogram signal including a fiducial point within said electrocardiogram signal;b) determining a selection of samples surrounding temporally said fiducial point, and based on values of electrocardiogram amplitude of said samples producing a parameter representative of said a cardiac cycle;c) determining if said parameter is out of an allowable range of said parameter, wherein the size of said range is adaptively determined based on previously-calculated values for said parameter; andd) declaring an axis shift if said parameter is out of said range for more than a predetermined amount of time.