Subcutaneous sensing feedthrough/electrode assembly

A sensing electrode system wherein one or more electrodes are disposed around the perimetric periphery of an implantable medical device (IMD), the sensing electrode system comprising:

• a first end integrated with a feedthrough conductor;
• insulator means having an opening to encase a segment of said first end;
• braze means to hermetically seal and integrally connect said first end with said insulator and said insulator with a ferrule;
• and
• a second end forming a large surface area extending through said ferrule;
• said first end being electrically coupled to a circuit in the IMD, said second end providing sensing to process physiologic signals obtained via said large surface area.

An implantable medical device (IMD) having a hermetically sealed housing having a housing outer wall exposed to the body and a housing inner wall enclosing sensing circuitry within said housing for processing electrical signals of the body detected between at least two sense electrodes supported by the housing, wherein;

• at least one sense electrode comprises a electrical feedthrough mounted to extend between said housing first side and said housing second side, said feedthrough comprising a ferrule having an inner ferrule surface extending between a ferrule first end and a ferrule second end, an electrically conductive feedthrough pin extending between a feedthrough pin first end and a feedthrough pin second end, and an electrical insulator extending between said feedthrough pin and said ferrule inner wall and supporting said feedthrough pin;
• and further comprising:
• means for mounting said ferrule wall first end to extend said feedthrough pin through said housing to expose said feedthrough pin first end to the body and to hermetically enclose said feedthrough pin second end within said housing;
• and
• means for electrically coupling said feedthrough pin second end with said sensing circuitry thereby enabling said feedthrough pin first end to function as a first sense electrode operable in conjunction with a second sense electrode coupled with the sensing circuitry to enable sensing of electrical signals of the body.