Patent ID: 7774049

Claim:
A medical device comprising: a housing containing electronic circuitry; and a plurality of electrodes coupled to the electronic circuitry that sense at least one cardiac signal, wherein the electronic circuitry comprises a processor that: analyzes the at least one cardiac signal on a beat-to-beat basis, determines a first characteristic of the at least one cardiac signal based on analyzing the at least one cardiac signal on the beat-to-beat basis, identifies a cardiac event based on the first characteristic of the at least one cardiac signal, in response to identifying the cardiac event, analyzes the at least one cardiac signal within at least one predetermined sensing window, the at least one predetermined sensing window comprising a predetermined duration of time unrelated to one or more beat-to-beat durations, determines a second characteristic of the at least one cardiac signal based on analyzing the at least one cardiac signal within the at least one predetermined sensing window, and identifies oversensing based on the second characteristic, wherein the processor transitions the medical device between a first state and a second state when the processor identifies the cardiac event.