Patent ID: 7805185

Claim:
A method, comprising: sensing, for a patient, a plurality of composite signals associated with an unknown number of sources using a plurality of implantable electrodes; performing a source separation using the sensed plurality of composite signals to separate signal components of the sensed plurality of composite signals according to their sources; producing one or more cardiac signal vectors associated with all or a portion of one or more cardiac activation sequences based on the source separation; detecting a change in a patient's posture between a first postural position and a second postural position different from the first postural position using the one or more cardiac signal vectors; determining whether the patient is in a predominant cardiac rhythm during the change in the patient's posture between the first and second postural positions; and determining, if the patient is in the predominant cardiac rhythm, that the detected posture change is indicative of the change in the patient's posture between the first and second postural positions and not due to a change in the patient's cardiac activation sequence.