Patent ID: 7751890

Claim:
A cardiac rhythm management device, comprising: one or more intra-cardiac sensing channels for sensing intrinsic cardiac activity and generating intra-cardiac electrogram signals; a sensing channel incorporating a subcutaneous electrode for generating a subcutaneous ECG signal wherein the subcutaneous electrode is mounted on an implantable housing for the device; a pacing channel for pacing a cardiac chamber; a controller for receiving sensing signals and controlling the delivery of pacing pulses in accordance with a programmed mode; and, wherein the controller is programmed to detect chamber senses in the subcutaneous ECG and intra-cardiac electrogram signals, cross-check the chamber senses detected in the subcutaneous ECG signal and the intra-cardiac electrogram signal to determine whether a chamber sense is detected in one signal but not the other, and set an alarm flag if a discrepancy is found to exist.