A pacemaker with determination of the dependence of the cardiac ejection of the av - delay

摘要

A pacemaker comprises a pulse generating means (12) for delivering stimulation pulses to a patient's heart and a controlling means (8) for controlling the delivery of stimulation pulses from said pulse-generating means. The controlling means comprises an altering means (10) for altering the AV-delay from a predetermined first AV-delay value to a predetermined second AV-delay value, and back to said first AV-delay value. A sensor (2) is provided to measure a parameter related to cardiac output of the patient. The sensor is adapted to measure the parameter in a time window inside a time of operation with said predetermined first AV-delay value, in a time window inside a time of operation with said predetermined second AV-delay value and in a time window inside a time of operation after the return back to said first AV-delay value. A determining means comprises a calculation means (6) for calculating an average value of the measured parameter during each of said time windows and the determining means uses said average values in determining which one of the AV-delay values results in a higher cardiac output.