Cardiac pacer electrode system

Claim 1

AN ELECTRICAL CARDIAC PACER FOR IMPLANTATION ENTIRELY WITHIN A BODY, COMPRISING A HOUSING ENCLOSING A CIRCUIT FOR PRODUCING CARDIAC STIMULATION SIGNALS, A FIRST ELECTRODE FOR APPLICATION TO A LOCATION ON THE HEART WITHIN SAID BODY, A SECOND ELECTRODE PROVIDING A RETURN PATH FROM SAID BODY TO SAID CIRCUIT, AND CONNECTIONS BETWEEN SAID ELECTRODES AND SAID CIRCUIT, CHARACTERIZED IN THAT SAID SECOND ELECTRODE IS OF SUBSTANTIALLY LARGER SURFACE AREA THAN SAID FIRST ELECTRODE, IN THAT THE CONNECTION BETWEEN SAID CIRCUIT AND SAID FIRST ELECTRODE IS LONGER THAN THE CONNECTION BETWEEN THE CIRCUIT AND SAID SECOND ELECTRODE AND EXTENDS IN A DIFFERENT DIRECTION WHEREBY THE SECOND ELECTRODE MAY BE LOCATED OUTSIDE THE REGION OF THE HEART, AND IN THAT SAID HOUSING INCLUDES A CONDUCTIVE WALL MEMBER COMPRISING SAID SECOND ELECTRODE.