Abstract: A body implantable lead assembly adapted to transmit electrical tissue stimulating signals between a proximal end portion of the lead assembly and a distal end portion of the lead assembly includes an electrical conductor extending between the proximal and distal end portions of the lead assembly for transmitting the electrical signals. The conductor has an enlarged, preferably ball shaped distal extremity comprising a termination element. The lead assembly includes a tip electrode having a proximal portion, a proximal extremity, a distal portion and a distal extremity, the distal extremity comprising an active electrode surface. At least the proximal portion of the tip electrode comprises a tubular structure, the tubular proximal portion having an inside diameter slightly smaller than the termination element on the distal extremity of the conductor. The tubular proximal portion of the tip electrode has formed within the wall thereof at least one longitudinally oriented, keyhole-shaped opening.

Abstract: A method of joining an electrically-conductive elongate member, which may be a multi-strand cable, to an electrically-conductive electrode, possibly for an implantable medical device, requires that the free end of the electrically-conductive member be inserted axially into a longitudinally extending passage of a tubular crimp/weld sleeve. Thereupon, the crimp/weld sleeve is crimped onto the electrically-conductive elongate member to achieve firm engagement between the crimp/weld sleeve and the electrically-conductive elongate member. The crimp/weld sleeve is provided with a radially outward extending prominent member which may be one of a variety of shapes. The electrode is tubular, overlies the outer surface of a longitudinally extending lead body, and is formed with an aperture defined by a rim having a transverse dimension greater than the transverse dimension of the prominent member.

Abstract: A connector assembly located at the proximal end of an elongated lead body includes first and second electrical contacts, each attached to a respective one of at least two conductors. An interlocking construction positively joins the first and second electrical contacts and maintains a fixed axial spacing therebetween. The first connector includes a connector pin having a head portion at an extremity thereof and an integral and coaxial tail portion and the second connector includes a connector ring coaxial with and telescopingly received on the tail portion. An electrically insulative male joint member integral with the tail portion is selectively lockingly engageable with a female joint member integral with the connector ring.

Abstract: An implantable medical electrical lead is made by forming a generally radially directed bore extending between each lumen of an elongated lead body having a plurality of internal longitudinally extending, circumferentially spaced lumina, the bores being located at longitudinally and circumferentially spaced locations, then drawing an elongated conductor cable into and through each lumen of the lead body such that a terminal end thereof projects through and beyond an associated one of the bores. A metallic tube is slidably attached onto each conductor cable adjacent the cable's terminal end, then is firmly joined to its associated conductor cable. Thereupon, each metallic tube is affixed, as by welding, preferably, by laser welding, to an associated one of a plurality of tubular electrodes coaxial with, and overlying, the lead body at longitudinally spaced locations. In one instance, the tubular electrode may be a ring electrode with the lead body connected to a pacemaker.

Abstract: A transvenous endocardial lead comprises an elongated flexible body member encompassing an electrical conductor which has an electrode at its distal end. A stabilizer adjacent the distal electrode extends outwardly from the flexible body member by a distance no greater than approximately one-half of the shortest distance between a longitudinal axis and the outer peripheral surface for minimizing dislodgment of the distal end from an intended implanted position into the myocardial tissue of the heart and for preventing penetration of the distal end of the flexible body member into the myocardial tissue. The stabilizer may be employed in conjunction with conventional active or passive fixation members and may take a variety of forms.

Abstract: An implantable pacing lead having a flexible insulative material injected into the passageway accommodating the electrical conductor(s) to encapsulate the conductor(s) for at least the portion of the lead body most subject to physical damage to in the lead body.

Abstract: An implantable pacing lead having a flexible insulative material injected into the passageway accommodating the electrical conductor(s) to encapsulate the conductor(s) for at least the portion of the lead body most subject to physical damage to in the lead body.

Abstract: A rotatable pin, screw-in type lead assembly includes a radiopaque element proximate the distal tip of the lead assembly for permitting direct, rapid fluoroscopic verification of the amount of extension of the helix electrode relative to the tip. The radiopaque element is preferably in the form of a metallic ring having a porous, tissue-engaging outer surface which promotes rapid tissue ingrowth and consequent lead stabilization. The lead assembly further includes a low friction seal assembly operatively associated with a shaft carrying the helix electrode. The seal assembly reduces the number of turns of the lead assembly connector pin required to effect lead fixation or removal.

Abstract: A rotatable pin, screw-in pacemaker lead assembly has a conductor coil enclosed within a silicone insulating tube. The conductor coil has a distal end secured to a helix electrode and a proximal end including a rotatable connector pin. The outer surface area of the conductor coil is coated with a super thin film of biocompatible Teflon. The Teflon coating substantially reduces the friction between the conductor coil and the inner wall of the insulating tube during lead fixation, thereby substantially reducing the number of turns of the connector pin required to effect fixation of the helix electrode.

Abstract: A patch electrode including a generally oval-shaped metallic mesh affixed to a polymer insulation backing and an insulation frame, and further including a plurality of specially designed lattices which divide the metallic mesh into a plurality of windows or apertures. The windows effectively act as smaller electrodes distributing the higher current densities inward from each of their own individual edges.

Abstract: A defibrillator patch lead having a connecting element interconnecting an electrical conductor and a wire mesh electrode pad. The connecting element includes a body portion which has a slot cut therein into which a portion of the wire mesh electrode is inserted and securely bonded, preferably by laser welding. The connecting element further includes a female connector portion which is designed to mate with a male core sleeve. The core sleeve includes a channel for receiving a first conductor therein, which is then electrically and mechanically connected (e.g., by either welding or crimping). The core sleeve also includes an orifice for receiving a second conductor, which is subsequently electrically and mechanically connected (e.g., by either welding or crimping) between the core sleeve and the connecting element. Advantageously, the combination of the core sleeve, two conductors, and the connecting element have superior pull strength over conventional methods of attachment.

Abstract: An electrical conductor assembly utilized, for example, in a defibrillator patch lead to interconnect a pulse generator and monitoring unit, and a wire mesh electrode pad. The electrical conductor includes a Teflon insulated drawn brazed stranded (DBS) wire cable which is wrapped in a drawn filled tube (DFT) wire multifilar coil encased in a biocompatible insulative tubing.

Abstract: A cardiac pacing lead having a plurality of individually insulated conductors arranged as a multifilar coil. The lead includes a connector assembly and a ring electrode assembly, each of which are optimized for use in conjunction with conductors arranged in the form of a multifilar coil. The connector assembly takes the form of an in-line connector having a plurality of linearly arranged connecting surfaces, each coupled to one of the conductors in the multifilar coil. The ring electrode assembly is constructed such that it displays the same outer diameter as the pacing lead. In both assemblies, conductors are coupled by means of welds, rather than by crimping or swaging.

Abstract: An electrical stimulation lead incorporating an electrode assembly which dispenses a drug adjacent the stimulation site. The lead is provided with a fixation helix located at the distal end of the lead. An electrode may be extended distally within the helix. When extended, the electrode serves as a guard against perforation or other damage to tissue by the helix. In its retracted position, the electrode is located roughly adjacent the distal end of the lead body, and lies against the tissue to be stimulated. Advancing and retraction of the electrode is accomplished by means of a stylet which is removably engageable with the proximal end of the electrode. In one embodiment, the stylet functions to both advance and retract the electrode. In an alternative embodiment, the stylet is used only to advance the electrode, and retraction of the electrode is accomplished by a resilient conductor.

Abstract: A cardiac pacing lead or other stimulation lead carrying a steroid compounded within a polymer matrix. The steroid is dispersed in thermoplastic or thermoset polyurethane or polyurea forming monomers or prepolymers. The mixture is then chain extended by addition of the appropriate difunctional or multifunctional isocyanate, hydroxyl or amine curing agent to form a solid polymer. The resulting formulation is molded or cast into a desired shape, and incorporated in the distal end of a medical electrical lead, adjacent to or within the electrode. In a preferred embodiment, the medical lead employs an extendable helix which is screwed into body tissue, and the polymer containing the drug takes the form of a generally dimensionally stable annular member mounted to the lead, encircling the helix.

Abstract: A cardiac pacing lead has a plurality of individually insulated conductors arranged as a multifilar coil. The lead includes a connector assembly and a ring electrode assembly, each of which are optimized for use in conjunction with conductors arranged in the form of a multifilar coil. The connector assembly takes the form of an in-line connector having a plurality of linearly arranged connecting surfaces, each coupled to one of the conductors in the multifilar coil. The ring electrode assembly is constructed such that it displays the same outer diameter as the pacing lead. In both assemblies, conductors are coupled by means of welds, rather than by crimping or swaging.

Abstract: A cardiac pacing lead having a plurality of individually insulated conductors arranged as a multifilar coil. The lead includes a connector assembly and a ring electrode assembly, each of which are optimized for use in conjunction with conductors arranged in the form of a multifilar coil. The connector assembly takes the form of an in-line connector having a plurality of linearly arranged connecting surfaces, each coupled to one of the conductors in the multifilar coil. The ring electrode assembly is constructed such that it displays the same outer diameter as the pacing lead. In both assemblies, conductors are coupled by means of welds, rather than by crimping or swaging.

Abstract: A system for delivering a drug to a patient according to the preferred embodiment of the present invention is shown as including a plunger assembly reciprocally received in a reservoir for forcing the drug therefrom for delivery to the patient. The plunger assembly is axially advanced by the rotation of a lead screw rotatably mounted and axially movable with respect to the chassis. In a first axial position, the end of the lead screw deflects contacts of a switch member into electrical engagement which interrupts operation of the motor which rotates the lead screw. The lead screw is biased out of its first axial position such that the first end of the lead screw does not actuate the switch member and rotation of the lead screw is not interrupted.