Abstract: A heart pacemaker including a captive sealing setscrew for securing and preventing leakage of body fluids to the catheter. The setscrew has a head of a material of high tensile strength, stiffness, resiliency, toughness and fatigue endurance, typically Delrin. The head is cylindrical but has a circumferential projection at its inner end. The pacemaker includes an internally threaded receptacle which is engaged by the setscrew as the setscrew is advanced to secure the catheter. Externally of this receptacle there is a sleeve of silicone rubber. At the outer end of the rubber sleeve there is a recess. Inwardly of the recess the rubber sleeve is of smaller internal diameter than the projection so that when the screw is screwed into the receptacle, a tight seal to prevent penetration of body fluids is formed by the projection and sleeve.

Abstract: A catheter to be electrically connected to a part of an organ of a body, typically, the muscle of the heart. The catheter includes a hollow electrical conductor having a resilient clamp at the end where it is to be connected. The clamp is manipulated by a manipulator which is removably inserted into the conductor or by a string which is permanently connected to the clamp. The jaws of the clamp are normally maintained closed by a spring. The spring is retracted by the manipulator or string which pulls on a pin connected to the spring permitting the jaws of the jaws to spring open. The open jaws are then positioned near the body part to be engaged and the manipulator or string is manipulated to release the spring so that the jaws are closed in engagement with the body part.The clamp extends to the conductor through a seal which effectively prevents the penetration of body fluids to the conductor.

Abstract: Organ-stimulating apparatus in which the catheter extends through a threaded cavity or socket and is held by an electrically insulating set screw that is screwed into the cavity and seals the cavity against the penetration of body fluids. The set screw includes a threaded member which extends from an insulating head. An O-ring extends around the periphery of the head and when the set-screw is screwed into the threaded member, the O-ring engages the wall of the cavity sealing the cavity against the penetration of body fluids.

Abstract: A method of making a pacemaker which includes, in a container a subassembly of, a battery nested in an electrical converter serving to produce heart-pacing pulses. This subassembly is encapsulated in a mold in rigid, polyurethane foam of low weight and capable of protecting the encapsulated components from shock. The body formed by prepotting is generally ellipsoidal and is nested snugly in one of the sections of an ellipsoidal container. Another section of the container is welded to the one section along the congruent rims. Additional potting material is injected through the boards between the sides of the encapsulated body and the adjacent walls of the container. The encapsulated body is held firmly in the container without potting material between the top and bottom and ends of the body and the container. The potting material is injected through the hole in which the electrical feedthrough is subsequently welded.

Abstract: A surgical tool for use in implanting a heart pacer. The tool includes a handle from whose one end an Allen wrench extends and in whose other end an O-ring plug having a stem is removably held by the stem. The wrench serves to screw an Allen-head set screw into the pacer to secure the terminal of the catheter which connects the pacer to the heart electrically. The plug seals the hole in which the set screw is inserted preventing electrical leakage by reason of penetration of body fluids to the terminal. The stem is removed from the plug and may serve to seal the suture hole in the pacer when the pacer is not sutured in place.

Abstract: A heart pacer to be implanted between the pectoralis major muscle and the skin a short distance below the clavicle having an outer container in the shape of an ovaloid. Such a heart pacer adapts itself positionally, cosmetically and with a minimum of discomfort to implantation.

Abstract: A nuclear heart pacer having a heat-to-electricity converter including a solid-state thermoelectric unit embedded in rubber which is compressed to impress hydrostatic precompression on the unit. The converter and the radioactive heat source are enclosed in a container which includes the electrical circuit components for producing and controlling the pulses; the converter and components being embedded in rubber. The portions of the rubber in the converter and in the container through which heat flows between the radioactive primary source and the hot junction and between the cold junction and the wall of the container are of thermally conducting silicone rubber.The primary radioactive source material Pu.sub.238 is encapsuled in a refractory casing of WC-222 (T-222) which in turn is encapsuled in a corrosion-resistant casing of platinum rhodium, a diffusion barrier separating the WC-222 and the Pt-Rh casings. The Pt-Rh casing is in a closed basket of tantalum.

Abstract: A heart pacer to be implanted between the pectoralis major muscle and the skin a short distance below the clavicle having an outer container in the shape of an ovaloid.[...]. .Iadd.being, except where the heart lead is connected, curved in all dimensions and free of corners and shape ends. .Iaddend.Such a heart pacer adapts itself positionally, cosmetically and with a minimum of discomfort to implantation.