An example
system includes an implantable
medical device (IMD) configured to: acquire an integrated bipolar electrogram (EGM)
signal of the first chamber sensed via a first lead implanted in a first chamber of the heart; and at least one of: identifying an intrinsic event of the second chamber sensed via a second lead implanted in a second chamber of the heart; or identifying a pacing event of the second chamber sensed via the second lead; and
processing circuitry configured to: generate a time window of the EGM
signal based on one or more of the identified intrinsic event or the identified pacing event; determine a value of a characteristic of the EGM
signal during the time window; determine that the value of the characteristic satisfies a far-field activity threshold; and adjust a sensitivity threshold of the IMD based on the determination that the value of the characteristic satisfies the far-field activity threshold.