An implantable cardiac stimulation device and associated method set an atrial
capture detection window by verifying that inter-atrial conduction is intact, and
then measuring the inter-atrial conduction time. The measured inter-atrial conduction
time may then be used for setting the atrial capture detection window. Capture
verification of a stimulated atrial site is then implemented by detecting a conducted
depolarization at another atrial site or in the opposite atrial chamber. A signal
received during an atrial capture detection window is compared to a depolarization
signal threshold or to a depolarization signal template in order to verify detection
of a conducted depolarization signal as evidence of capture at the stimulated site.
By sensing depolarization signal away from the stimulated site, the negative effects
of lead polarization normally encountered when detecting an evoked response are avoided.
