Patent ID: 8343049

Claim:
A system comprising: an implantable medical device, the implantable medical device comprising: a posture sensing circuit configured to detect a change within a recumbent posture of a subject; a physiological signal sensing circuit to sense a physiological signal; a controller circuit, operatively coupled to the physiological signal sensing circuit and the posture sensing circuit, the controller circuit configured to detect a change in the physiological signal that occurs in association with the detected change within the recumbent posture of the subject, wherein the physiological signal sensing circuit includes at least one of a heart rate sensing circuit, a blood pressure sensing circuit, a heart sound sensing circuit, a heart rate variability sensing circuit, and a respiration rate sensing circuit, and the change in the physiological signal includes at least one of: a sensed change in heart rate that is less than a normal subject's change in heart rate; a sensed change in blood pressure that is different from a normal subject's change in blood pressure; a sensed change in heart sound energy that is different from a normal subject's change in heart sound energy; a sensed change in heart rate variability that is different from a normal subject's change in heart rate variability; and a sensed change in respiration rate, respectively, and wherein the controller circuit is further configured to generate a response as a function of the detected change in the physiological signal; and a circuit to compare the change in the physiological signal, the comparison comprising a comparison between (1) a ratio of the physiological signal in the first recumbent posture to the physiological signal in the second recumbent posture for a subject with a possible health condition, to (2) the ratio of the physiological signal in the first recumbent posture to the physiological signal in the second recumbent posture for a normal subject or population.