Patent ID: 7941206

Claim:
A system, comprising: a plurality of implantable electrodes configured for sensing a plurality of composite signals associated with an unknown number of sources, the plurality of implantable electrodes comprising at least three spatially separated implantable electrodes; a housing configured for implantation in a patient; a control circuitry provided in the housing; a memory provided in the housing; a processing circuitry provided in the housing and coupled to the memory, the processing circuitry configured to perform a source separation that separates signal components of the sensed plurality of composite signals according to their sources to produce a set of signal vectors, the processing circuitry configured to: select, from the set of signal vectors, a target vector associated with a target signal, the target vector representative of a signal vector of the set of signal vectors associated with higher quality cardiac data relative to other signal vectors of the set of signal vectors; detect a change in a predetermined condition or an event occurrence indicating that changing which signal vector of the set of signal vectors is selected as the target vector may be useful in sensing cardiac activity; and update, in response to the change in the predetermined condition or event occurrence, selection of the target vector by performing a subsequent source separation on the detected plurality of composite signals and reselecting the same or a different signal vector associated with higher quality cardiac data relative to other signal vectors of the set of signal vectors as the target vector based on the subsequent source separation; and communications circuitry provided in the housing and configured to facilitate communication of information between the housing and a device external of the housing.