DUAL CHAMBER CARDIAC PACEMAKER EMPLOYING HYSTERESIS TO MAXIMIZE THE NUMBER OF NORMALLY CONDUCTED VENTRICULAR BEATS WITH AN OPTIMUM A-V DELAY FOR PACED VENTRICULAR BEATS

摘要

A DDD pacemaker including stimulating means to stimulate theventricles of a heart after a predetermined A-V delay periodincludes means for adjusting the A-V delay period to enhance theprobability of detecting naturally occurring ventriculardepolarization signals when such signals are being detected at apredetermined rate and switching to a more hemodynamicallyappropriate A-V delay period when paced beats predominate. Theinvention is implemented in software run on a microprogrammablecontroller comprising the DDD pacemaker.