Patent ID: 8435185

Claim:
A method of detecting a cardiac event by a medical device, comprising: sensing cardiac signals from a plurality of electrodes, the plurality of electrodes forming a first sensing vector and a second sensing vector; separately identifying the first sensing vector and the second sensing vector as being corrupted by noise in response to determining a signal energy content metric of corresponding sensed cardiac signals not being within predetermined limits; separately identifying the first sensing vector and the second sensing vector as being corrupted by noise in response to determining a noise to signal ratio of corresponding sensed cardiac signals not being less than a signal to noise threshold; separately identifying the first sensing vector and the second sensing vector as being corrupted by noise in response to determining corresponding sensed cardiac signals being associated with muscle noise; separately identifying the first sensing vector and the second sensing vector as being corrupted by noise in response to determining a mean frequency of corresponding sensed cardiac signals not being less than a mean frequency threshold; otherwise, separately identifying the first sensing vector and the second sensing vector as not being corrupted by noise; and delivering therapy via the device in response to the identifying.