Detection of ventricular ectopic beats using ventricular electrogram

摘要

A method of accurately determining if ectopic beats are occurring in the heart by detecting the time interval, T, between a point Q* defined is the onset of the QRS complex and the peak value of R (T=Q*R) during a heart beat cycle and comparing that time with a running mean value calculated from normal heartbeats. A beat is identified as an ectopic beat if the Q*R time interval for a current beat is at least four standard deviations from the mean Q*R time interval of normal preceding beats. The electrodes for detecting the ectopic beats may be inside the patient's heart or on the patient's skin. If more than one electrode is used for monitoring the depolarization of the heart, then by combining the Q*R intervals (e.g. using a triangulation method) calculated from different electrodes, the location of the ectopic excitation can be determined and identified. The method of determining and localizing ectopic beats may be used in a pacing device to initiate ectopic beat handling procedures and to analyze the nature and possible trend of ectopic activities. This method of using the Q*R interval is independent of the PR or RR intervals normally measured and used to detect early ectopic beats and is therefore a more accurate method, since ectopic beats may occur at any time independent of PR or RR intervals.