An implantable, multi-chamber cardiac stimulation device and method automatically
adjust inter-chamber stimulation delays whenever stimulation rate is changed according
to a patient's metabolic need. Inter-chamber stimulation delays include inter-atrial
delays, inter-ventricular delays, and atrio-ventricular delays. Inter-chamber stimulation
delays are defined according to whether the event which triggers the start of the
delay is an intrinsic sensed event or the delivery of a stimulation pulse. Adjustment
to inter-chamber stimulation delays is made as a function of the stimulation rate
changes. By providing automatically adjustable inter-chamber stimulation delays
optimal synchronization of heart chamber contractions may be maintained at all
stimulation rates.