Abstract: A device (10) for removing from a patient (12) a previously implanted elongated structure (14), such as a catheter, sheath, defibrillator lead, pacemaker lead (15) or the like. The device (10) includes a snare (24) which encircles and reversibly grasps either the proximal end (16) or the distal end (20) of the elongated structure (14), as well as a sheath member (22) for delivering the snare (24) to the particular end (16 or 20) of the structure (14) to be grasped.

Abstract: Heart lead removal apparatus for removing an implanted cardiac pacemaker lead from the wall of a heart through a blood vessel leading to the heart. The lead removal apparatus comprises an outer tube sized for insertion into the coiled structure passageway of the pacemaker lead; an anchoring projection positioned proximate the distal end of the outer tube; and a stylet positioned through the passageway of the outer tube for urging the anchoring projection between relaxed and hooked positions. In the hooked position, the projection extends outwardly from the outer tube and when also positioned in the coiled structure passageway, hooks into the coiled structure for facilitating removal of the lead from the heart. In the relaxed position, the anchoring projection is insertable into the coiled structure passageway.

Abstract: A multi-leaflet (usually trileaflet) heart valve composed of biocompatible polymer which, in all of its embodiments, simultaneously imitates the structure and dynamics of biological heart valves and avoids promotion of calcification. The valve includes a plurality of flexible leaflets dip cast on a mandrel, which leaflets are then bonded with a bonding agent to the interior surfaces of a plurality of struts on a metal-reinforced prosthetic stent. The leaflets open and close in response to the pumping action of the heart and, due to the design of the leaflets, fatigue resistance of the heart valve is high. The leaflets and the polymer components of the prosthetic stent are manufactured of biocompatible polymers exhibiting intrinsic calcification-resistant properties.

Abstract: Heart lead removal apparatus and method are disclosed for removing a heart lead from the wall of a heart through a blood vessel leading to the heart. The apparatus comprises a flexible stylet wire with an expandable wire coil attached to the distal end for engaging the coiled structure of the heart lead. The wire coil includes first, second, and third pluralities of turns. The first plurality of turns is positioned around and about the distal end of the stylet wire for radially expanding when in the passageway of the lead to secure the stylet wire to the lead. The second plurality of turns extends proximally from the first plurality of turns and laterally from the stylet wire for engaging the lead and radially expanding the first plurality of turns. The third plurality of turns extends distally from the first plurality of turns and is attached around and about the distal end of the stylet wire for cooperating in the radial expansion of the first plurality of turns when in the passageway of the lead.

Abstract: Cardiac output is measured using an injected substance (indicator) that changes the conducting property (electrical resistivity) of blood, provided the indicator has a different resistivity from that of blood. A new type of electrically compensated tetrapolar conductivity cell located at the distal end of an intravascular catheter is disclosed. The conductivity cell consists of four electrodes arranged across the end of a catheter at its tip. The outer electrodes used for current injection are enlarged to reduce the electrode-electrolyte interface impedance. Capacitance compensation of the cather/tetrapolar conductivity cell provides reliable and repeatable blood resistivity measurements. The catheter further includes a calibration resistor thereby eliminating a calibration step previously necessary in using such a catheter for measuring cardiac output.

Abstract: Heart lead removal apparatus and method are disclosed for removing a pacemaker lead from a heart through a blood vessel leading thereto. The apparatus comprises a flexible stylet wire with an expandable wire coil attached to the distal end for engaging the coiled structure of the pacemaker lead. A lockable mechanism grasps the proximal end of the lead, and a wire guide is inserted in the passageway of the lead to determine its size and clear any blockage therein. The stylet wire is inserted in the longitudinal passageway of the coiled structure to the distal end of the pacemaker lead. The stylet wire is rotated in a direction to unwind and expand the wire coil and engage the coiled structure, thereby securing the stylet wire to the pacemaker lead. A tie secures the insulating material to the coiled structure of the lead at the proximal end thereof to limit motion and to apply a uniform extraction force to the entire lead.

Abstract: Heart lead removal apparatus and method are disclosed for removing a heart lead from the wall of a heart through a blood vessel leading to the heart. The apparatus comprises a flexible stylet wire with an expandable wire coil attached to the distal end for engaging the coiled structure of the heart lead. A lockable mechanism grasps the proximal end of the lead, and a wire guide is inserted in the passageway of the lead to determine its size and any blockage therein. The stylet wire is inserted in the longitudinal passageway of the coiled structure to the distal end of the heart lead where the tip is typically secured to the heart wall with a number of tines formed from the insulating material surrounding the coiled structure. A tie secures the insulating material to the coiled structure of the lead at the proximal end thereof to limit motion and apply uniform extraction force to the entire lead.

Abstract: Heart lead removal apparatus is disclosed for removing a heart lead from the wall of a heart through a blood vessel leading to the heart. The apparatus comprises a flexible stylet wire with an expandable wire coil attached to the distal end for engaging the coiled structure of the heart lead. The stylet wire is inserted in the longitudinal passageway of the coiled structure to the distal end of the heart lead where the tip is typically secured to the heart wall with a number of tines formed from the insulating material surrounding the coiled structure. When inserted, the stylet wire is rotated in a direction to unwind and expand the wire coil and engage the heart lead coiled structure, thereby securing the stylet wire to the heart lead. A separator tube is inserted over the proximal end of the stylet wire and the heart lead and moved along the entire length of the heart lead to first separate the restricted heart lead from the blood vessel leading to the heart cavity.

Abstract: Heart lead removal apparatus and method are disclosed for removing a heart lead from the wall of a heart through a blood vessel leading to the heart. The apparatus comprises a flexible stylet wire with an expandable wire coil attached to the distal end for securing the distal end of the stylet wire to the heat lead. A catch wire extends from the proximal end of the wire coil. The free end of the catch wire has a segment folded back on itself for engaging the coiled structure of the lead and expanding the wire coil when the stylet wire and wire coil are rotated in the passageway of the lead. The stylet wire is inserted in the longitudinal passageway of the coiled structure to the distal end of the heart lead. When inserted in the passageway, the stylet wire and wire coil are rotated in a direction to engage the catch wire with the coiled structure. The wire coil then expands engages the heart lead coiled structure, thereby securing the stylet wire to the heat lead.

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.