Patent ID: 7499750

Claim:
An implantable cardiac device, comprising: a pulse generator comprising a controller configured to execute program instruction stored in memory, the pulse generator and the memory provided in a can configured for implantation; a rigid support structure coupled to, and spaced apart from, the can; and a plurality of implantable electrodes coupled to the pulse generator, the rigid support structure configured to maintain the plurality of implantable electrodes in respective subcutaneous extra-thoracic locations and in a spaced relationship with respect to cardiac tissue and vasculature, the plurality of electrodes comprising: a first combination of electrodes mounted to the support structure in a fixed spaced relationship along a first plane with respect to other electrodes of the plurality of implantable electrodes, the first electrode combination positioned on the support structure in a manner to preferentially sense a first type of signal relative to other electrodes of the plurality of implantable electrodes; and a second combination of electrodes mounted to the support structure in a fixed spaced relationship along a second plane with respect to other electrodes of the plurality of implantable electrodes, the second electrode combination positioned on the support structure in a manner to preferentially sense a second type of signal relative to the electrodes of the first electrode combination, wherein the first plane is in an orthogonal relationship with respect to the second plane and controller execution of the program instructions causes the implantable cardiac device to select one of the first combination of electrodes or the second combination of electrodes for sensing a cardiac signal as the first type or the second type of signal, select the other of the first combination of electrodes and the second combination of electrodes for sensing a noise signal as the other of the first type and the second type of signal, and remove content from the cardiac signal based on the content of the noise signal, the selection of the first combination of electrodes or the second combination of electrodes for sensing the cardiac signal and the other of the first combination of electrodes and the second combination of electrodes for sensing the noise signal based on a test performed using the plurality of electrodes.