Endocardial lead having helically wound ribbon electrode

Claim 1

An endocardial lead comprising: an elongated, flexible, insulative tubing having proximal and distal ends, said insulative tubing having an aperture extending through the wall of said tubing at a predetermined position along the length of said tubing; an elongated, flexible, central conductor positioned within said insulative tubing, said central conductor having an insulative coating surrounding said central conductor over substantially the entire length thereof except for proximal and distal end portions of said central conductor; the proximal end portion of said central conductor being connected to an electrical connector adapted for connection to a pulse generating device; an elongate ribbon-shaped flat conductive bonding member extending generally parallel to the axis of said tubing on said tubing, having a length substantially greater than its width, and having one end electrically connected to said distal end portion of said central conductor within said insulative tubing, said elongate ribbon-shaped bonding member extending from said aperture and along and on the outer surface of said insulative tubing for essentially the full length of said bonding member; and a continuously wound ribbon-shaped conductive electrode having a generally rectangular cross-section and being helically wound with a plurality of closely spaced turns around the outer surface of said insulative tubing and having flat side surfaces thereof over and in direct electrical contact with said flat ribbon-shaped bonding member for substantially the entire length of said bonding member to thereby provide a low impedance electrical connection between said plurality of closely spaced turns of said ribbon shaped electrode and said central conductor and between adjacent turns of said ribbon-shaped electrode.