Patent ID: 8406862

Claim:
A cardiac monitor for estimating the value of a heart signal parameter, the monitor comprising: (a) a plurality of sensors for sensing first and second analog signals from a human heart; (b) a device coupled to the plurality of sensors, the device having an analog-to-digital circuit system contained therein for digitizing the first and second analog signals to produce first and second digitized waveforms; (c) a processor electrically coupled to the analog-to-digital circuit system, said processor configured to: (i) compute first and second pluralities of values of a heart signal parameter from the first and second digitized waveforms respectively, wherein first and second subsets of the first and second pluralities of values are characterized by first and second statistical distributions respectively that are characterized by first and second dispersions respectively; (ii) compute a first metric based on the first plurality of values normalized according to the first dispersion, wherein the first metric is indicative of the distance between at least one of the first plurality of values and a statistical parameter associated with the first statistical distribution; (iii) compute a second metric based on the second plurality of values normalized according to the second dispersion, wherein the second metric is indicative of the distance between at least one of the second plurality of values and a statistical parameter associated with the second statistical distribution; and (iv) apply a test to detect a cardiac event, wherein the test is based on a third metric that is a function of both the first and second metrics.