Patent ID: 7702389

Claim:
A cardiac pacemaker including: a. at least one stimulation pulse generator (A-STIM, RV-STIM, LV-STIM) selectively generating a stimulation pulse for delivery to one of at least two different chambers of a heart, the chambers including right and left atria and right and left ventricles, b. at least one impedance measuring stage (I, U, IMP), the impedance measuring stage being connectable to electrodes, and measuring an intracardiac impedance when in use, c. a control unit (CTRL) connected to the stimulation pulse generator and to the impedance measuring stage, the control unit being adapted to: (1) process a minimum impedance value for a heart cycle or for an impedance curve averaged over several heart cycles, (2) trigger stimulation pulses for two different chambers of the heart with an adjustable time delay (VVD, AVD), and (3) adjust the time delay depending upon the measured intracardiac impedance minimum value, wherein the control unit is adapted to adjust the time delay such that the minimum value of the intracardiac impedance during one heart cycle is minimized.