Abstract: A probe for an implanted medical device, more particularly for a cardiac pacemaker. The probe (10) has at its extremity a cylindrical body (14) supporting one or more electrodes (18) and a means of anchorage (34) extending radially around the exterior. A deformable sleeve (24), made of a supple material, covers the cylindrical body and supports the anchorage means. The sleeve has one end (or part) (26) attached to the body at the distal extremity of the probe, and one part (28) that is free or unconnected to the body spreading proximally in relation to the attached part and supporting the anchorage means. The free part is essentially applied in a separable manner against the body on the aforementioned distal region.

Abstract: A system for passively anchoring mid-lead electrodes on an endocardial catheter lead includes at least one fibrosis-anchoring opening positioned along the exterior surface of the catheter lead body proximal or distal to the mid-lead electrodes for passively securing the catheter lead against the interior wall of the heart. Within the fibrosis-anchoring openings a suitable material is provided for anchoring the catheter lead body to the heart wall by fibrosis. Preferably, the fibrosis-anchoring openings comprise at least a pair of openings positioned only partially around the exterior of the catheter lead body at locations both proximal and distal to the mid-lead electrodes, with the catheter lead body between the fibrosis-anchoring openings being pre-formed to bias the mid-lead electrodes against the heart wall.

Abstract: A single preformed catheter configuration for a dual-chamber pacemaker system is provided. The catheter is formed of a heat-settable biocompatible material such as, for example, polyether polyurethane, and is formed in a predetermined shape to enhance and stabilize atrial electrode contact on the inner wall of the atrium, while also providing stress relief to absorb stresses occasioned by cardiac depolarization and respiration and modulation of the bulk cardiac complex. To this end, the catheter of the present invention includes a first section disposed in the superior vena cava to provide substantially stable support to the catheter, a second section disposed in the atrium and being preformed to substantially conform to the inner wall of the atrium, and a third section having a pliancy greater than that of the first two sections and being disposed distally of the second section.

Abstract: A lead assembly adapted for transvenous implantation into a human heart is provided. The lead assembly includes a connector for electrical connection to a cardiac stimulator. An elongated sheath assembly projects from the connector. The sheath assembly includes an inner elastic insulating sheath that includes a coextensive lumen for receipt of a stylet. An outer elastic insulating sheath is disposed around the inner sheath, thereby defining an elongated annular space. The outer sheath has an aperture that defines a gripping region. A biasing wire is disposed in the annular space. The biasing wire is connected to the connector proximally and is approximately coterminous at its distal end with the outer sheath. The biasing wire has a plurality of coils exposed by the aperture in the gripping region. By first stretching and then relaxing the lead assembly, the coils of the biasing wire pinch small portions of the myocardium to laterally fix the lead assembly at a given location in the heart.

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: A continuous sheath of open-celled porous plastic, preferably ePTFE, is used on the outside of an implantable lead, extending along the lead body and the electrodes, in such a way that the lead is isodiametric along its length, and is very strong in tension as is required for lead removal. Because the plastic is open-celled, when the pores are filled with saline, the lead can deliver defibrillation energy through the pores in the plastic. Pore size is chosen to discourage tissue ingrowth while allowing for defibrillation energy delivery through it.

Abstract: A cardiac stimulator lead and sleeve for anchoring the lead at its point of entry into a vein. More particularly, the present invention comprises a helical coil made of a resilient material that is capable of being uncoiled and wrapped around the lead and/or the vein such that it is biased to resume its fully coiled state and thereby frictionally engages the vein and or lead and functions as an anchoring device for the lead.

Abstract: A medical electrical lead having active fixation which readily flexes within the cardiac tissue through a fixation mechanism which is temporarily rigid. In a preferred embodiment, the medical electrical lead features a fixation helix constructed from an absorbable material, such as mannitol. In an alternate embodiment a medical electrical lead is disclosed which features a fixation mechanism having a multi-layer construction. In that embodiment the fixation mechanism is fashioned of a first, rigid and absorbable, material and a second, readily pliable and nonabsorbable, material. Through such a construction the lead may be fixed in the tissue such that over time the first material is absorbed by the body and the second material is left in position to flexibly fix the lead in place. In one embodiment the second material is conductive and is used to achieve an electrical coupling to the body tissue.

Abstract: A body implantable flexible lead assembly, adapted to transmit electrical pulses between a proximal end of the lead assembly and a distal end of the assembly to stimulate selected body tissue, includes a tubular, insulating housing connecting the proximal and distal ends of the assembly and having a central, longitudinal axis. At least two coiled, insulated conductors extend between the proximal and distal ends of the assembly for transmitting electrical signals, the coils of the at least two insulated conductors having substantially the same diameter. One of the coiled conductors is rotatable about the longitudinal axis relative to the other coiled conductor(s) and has a proximal end and a distal end.

Abstract: A lead system for use with an implantable cardioverter/defibrillator is disclosed. The lead system includes a fixation hook positioned approximately half-way between the distal tip of the lead and the tricuspid valve. The distal tip of the lead is positioned at the apex of the right ventricle and may or may not be secured there by a second fixation means such as a screw tip or tines. The fixation hook allows the defibrillation electrode to be accurately positioned by the patient's surgeon and maintained in contact with the septum wall of the patient's heart. By providing such intimate contact between the defibrillation electrode and the septum wall, defibrillation thresholds are reduced.

Abstract: A lead system for use with an implantable pacemaker/cardioverter/defibrillator. The lead system includes a securable pace/sense electrode positioned between the distal tip of the lead and the tricuspid valve. The distal tip of the lead is positioned at the apex of the right ventricle and may or may not be secured there by a second fixation means such as a screw tip or tines. The securable pace/sense electrode allows the defibrillation electrode to be accurately positioned by the patient's surgeon and maintained in intimate contact with the septum wall of the patient's heart, thereby reducing defibrillation thresholds; it provides a sense signal from the region of the His bundle or AV node, which can be used with other electrodes to distinguish between various arrhythmias; and it provides more physiologic pacing leading to greater cardiac output.

Abstract: The present invention is a transvenous lead having an anchoring sleeve retaining device. The transvenous lead features a lead covered by an insulative sleeve. Positioned at the distal end of the lead is an electrode assembly. Also positioned proximate the electrode assembly is a fixation mechanism. At the proximal end of the lead body is a terminal assembly. The terminal assembly permits the lead to be connected to a pulse generator. The anchoring sleeve retaining device further features a removable portion that frictionally engages the lead and prevents the anchoring sleeve from sliding along the lead prior to suturing the anchoring sleeve to the lead.

Abstract: An implantable pacing lead with a reinforcing sheath covering a portion of the lead body to prevent physical stress damage to the lead body. The reinforcing sheath includes a metal coil or ribbon encased in a biocompatible polymer which is positioned about a portion of the lead body.

Abstract: A lead for use with an implanted pulse generator which may be a pacemaker or defibrillator or combination thereof. The lead can deliver an electrical charge to cardiovert or defibrillate the ventricles of the heart via a large surface area defibrillation electrode which is passively implanted in the ventricle. The defibrillation electrode is designed to produce a uniform defibrillation charge distribution.

Abstract: A device for preventing a fixation element on the distal end of an implantable lead, during introduction into a body cavity, from coming into contact with and damaging the cavity has a protective body, which completely encloses the fixation element, and which is made of a gel-forming material. After introduction and contact with body fluid and when pressure is applied to the material against body tissue, the material permits mechanical penetration of the protective body by the fixation element, whereupon the fixation element can be affixed to the body cavity.

Abstract: An apparatus for preventing an anchoring element on the distal end of an implantable medical electrical conductor from coming into contact with and damaging the wall of a body cavity during advancement of the conductor into the cavity has a sleeve element attachable to the outer surface of the distal end of the conductor to enclose the entire length of the anchoring element, and a pulling element attached to the distal end of the sleeve element. Pulling on the pulling element from the proximal end of the conductor retracts the sleeve element after introduction of the conductor has been concluded, to expose the anchoring element for active fixation to adjacent body tissue. An implantable electrode cable equipped with such an end protector.

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 suture sleeve for anchoring the lead body of an implantable medical device is fabricated of a biocompatible, polymeric material to which has been added color pigment in clear contrast with the bodily tissue adjacent the sleeve. The sleeve is therefore readily visible to the naked eye to aid the physician in locating the sleeve during lead implant or lead revision. Furthermore, the tubular body may be radiopaque and, therefore, easily seen on a fluoroscope through the addition of a radiologically dense material, such as tantalum powder, to the plastic from which the sleeve is molded.

Abstract: A system for lead removal of both heart pacemaker leads and cardioverter-defibrillator endocardial leads comprising a flexible coil of flattened ribbon. Preferably, the ribbon is comprised of polyethylene or another suitable biologically compatible material. At a distal end of the coil, a cutting surface may be provided, such as a chisel-like edge at the distal end of the coil. A handle may be provided for twisting the coil onto the lead. The coil should be at least partially radiopaque or provided with a surface which is radiopaque so that its use may be observed in the body by fluoroscopy or other suitable means.

Abstract: An electrode device, for intracardiac stimulation of heart tissue and/or sensing heart signals in a patient, has an electrode cable containing at least two elongate, flexible conductors, insulated from each other, and with an electrode head, arranged at the distal end of the electrode cable and at least two conductive surfaces, each connected to a separate conductor. In order to permit the distance between the conductive surfaces to be varied over a continuous range, simply and easily, the electrode head has at least two parts, moveable in relation to each other, each part being provided with at least one conductive surface, and the a control element is movably arranged at the distal end of the electrode cable immediately behind the electrode head, so any change in the position of the control element causes the control element to act on the parts of the electrode head such that the distance between the conductive surfaces is varied.

Abstract: An implantable endocardial lead with a retractable helix. A specialized stylet can be inserted into the lead at the proximal end and passed through the lead to the distal end. Located at the distal end of the lead is a piston supporting the helix. The piston is attached to a coiled trifilar conductor and has an electrode adjacent the helix. Immediately adjacent the piston proximally an additional first short coil of wire is interlocked between the wires of the trifilar conductor, providing a female thread within the conductor. The stylet has a second single strand short coil segment spot welded to the stylet adjacent a distal end thereof. The stylet is rotated to screw the second short coil segment on the stylet into the first short coil adjacent the piston.

Abstract: An electrode apparatus, such as an intravascular or intracardiac pacemaker or defibrillation electrode with an electrode cable has a jacket of insulation enclosing a first elongated, flexible conductor, connected to a first electrode arranged on the electrode cable, and also enclosing at least a second conductor, connected to a conductive surface forming a second electrode arranged on the electrode cable at a distance from the first electrode.

Abstract: A lead having a defibrillation electrode that is deployed for defibrillation using artificial muscle. In an undeployed position, the defibrillation electrode is small in diameter so as to be easily implanted pervenously and nonobstructive to cardiac contraction and blood flow. In a deployed position the defibrillation electrode is larger in diameter for defibrillation shock delivery. Thus, the electrode forces an increased amount of current to flow through the heart muscle during shock delivery to depolarize the majority of the cardiac tissue with a minimum of energy, while not obstructing blood flow at other times when not used for energy delivery.

Abstract: A medical electrical lead with an elongated lead body containing an elongated conductor and carrying a tip electrode mounted to and extending the distal tip of the lead body, coupled to the conductor. The distal tip of the lead body includes flange portions extending radially outward from a point immediately adjacent to the electrode and flat portions extending longitudinally and proximally from the electrode. The flange portions and flat portions alternate around the circumference of the lead body tip.

Abstract: A transvenous implantable defibrillation lead includes a conductor and inner and outer coaxial cylindrical electrodes. The inner electrode is connected to the conductor, and the outer electrode is connected to a sheath overlying the conductor in rotatable relationship thereto. The sheath is fixed to the outer cylindrical electrode so that rotation of the sheath relative to the conductor results in rotation of the inner and outer cylindrical electrodes relative to each other. The inner electrode has a plurality of hooks extending generally transversely and tangentially thereto, with the hooks being biased such that the terminal ends of the hooks tend to spring outwardly from the inner electrode. The hooks are constrained against the inner cylindrical electrode by the outer cylindrical electrode, except that a window in the outer electrode permits the hooks to spring outwardly therethrough upon rotation of the outer electrode relative to the inner electrode.

Abstract: A medical lead which has a reinforced tine assembly. In particular, the medical electrical lead of the present invention features an elongated lead body covered by an insulative sheath. Positioned upon the proximal end of the lead body is a terminal assembly. Terminal assembly permits the lead to be connected to a pulse generator. Positioned at the distal end of the lead body is an electrode. Also positioned proximate the electrode is a tine assembly. The tine assembly is preferably made from a insulative bio-compatible material, preferably silicone. The tine assembly further features a reinforcement to prevent the tine assembly from elongating. In the preferred embodiment, a polyester is used to provide reinforcement member.

Abstract: An implantable devices for the effective elimination of an arrhythmogenic site from the myocardium is presented. By inserting small biocompatible conductors and/or insulators into the heart tissue at the arrhythmogenic site, it is possible to effectively eliminate a portion of the tissue from the electric field and current paths within the heart. The device would act as an alternative to the standard techniques for the removal of tissue from the effective contribution to the hearts electrical action which require the destruction of tissue via energy transfer (RF, microwave, cryogenic, etc.). This device is a significant improvement in the state of the art in that it does not require tissue necrosis.In one preferred embodiment the device is a non conductive helix that is permanently implanted into the heart wall around the arrhythmogenic site.

Abstract: A transvenous lead system for cardiac stimulation with a pacemaker or implantable defibrillator having automatic activation of a passive fixation system. The lead includes an insulative lead body such as silicone rubber and has a proximal end with a connector for coupling the lead to the pacemaker or defibrillator. At least one conductor extends through the lead body for connection to a lead electrode. The lead further includes a plurality of flexible tines. In a first position, the tines are folded back along the lead body and exhibit a minimal profile. A hydrophilic material such as a hydrogel is disposed on the under side of each tine either as part of the tine or between the tine and the lead body. Upon exposure to body fluids when the lead is implanted, the hydrogel absorbs liquid and expands. This expansion forces the tines into a second, deployed position where the tines can engage trabeculae of the heart chambers to anchor the lead in place.

Abstract: A body implantable lead is provided, suitably a pacing lead for delivering pacing stimulus pulses to a patient, the lead having a fixation element such as a helix at its distal tip. The lead is provided with a soluble covering over the helix, which covering presents a smooth surface during insertion of the lead transvenously and dissolves away after a predetermined time in the patient's body, thereby exposing the anchor element. The lead is further improved by combining a radiopaque or angiographic contrast material with the protective coating, so that the physician carrying out the implantation procedure can monitor and see exactly when the coating has dissolved, whereupon the fixation element can be directly attached to the patient's heart wall.

Abstract: A lead is provided which assists in the implantation of the lead within an artery or vein of a human heart. The lead includes a lead body having a distal end and a proximal end and at least one electrode carried by the lead body intermediate the distal end and the proximal end. The lead includes a guide tip carried by the lead body which extends distally from the lead body distal end. The guide tip includes a distal tip end and a tapered portion forming the distal tip end. The tapered portion is curved in a direction of curvature to offset the distal tip end in a direction from the longitudinal center axis of the lead body. The guide tip may further include tines or fibrotic tissue ingrowth sites for retaining the lead in place after implantation.

Abstract: A lead for use with a pacemaker in a pacing system, the lead having at least one electrode placed at its distal tip and a helical fixation member at the lead distal tip for screwing the lead into a patient's heart wall. The helical member is composed of shape-memory metal and until use is encapsulated in a shrunken state with a diameter less than the diameter of the lead casing. The encapsulation material is preferably mannitol or a like material which dissolves when placed in the human heart. The shape-memory helix when released from the encapsulation material assumes an expanded diameter, greater than electrode diameter and preferably greater, so that when it is screwed into the heart wall, the helical coils are displaced radially away from the outer edge of the tip electrode. By this design, the damage to the heart tissue caused by the helix does not affect the heart wall immediately proximate to the tip electrode.

Abstract: A lead system for use with an implantable cardioverter/defibrillator is disclosed. The lead system includes a fixation hook positioned approximately half-way between the distal tip of the lead and the tricuspid valve. The distal tip of the lead is positioned at the apex of the right ventricle and may or may not be secured there by a second fixation means such as a screw tip or tines. The fixation hook allows the defibrillation electrode to be accurately positioned by the patient's surgeon and maintained in contact with the septum wall of the patient's heart. By providing such intimate contact between the defibrillation electrode and the septum wall, defibrillation thresholds are reduced.

Abstract: An intravenous lead for use with a cardiac device for implantation in the coronary sinus or the coronary sinus and great cardiac vein of the heart provides positive fixation for the lead when implanted in the coronary sinus or the coronary sinus and great vein of the heart. The lead includes a lead body adapted to be fed into the coronary sinus and great vein of the heart of a patient and at least one electrode carried by the lead body and adapted to be coupled to the implantable cardiac device. The lead body includes a preformed section having a resiliently coiled configuration. The coiled section is a left-handed turned coiled section which provides superior positive fixation of the lead as compared to right-handed turned coiled sections for use in the coronary sinus and great cardiac vein.

Abstract: A heart signal sensor 11 is connected by a flexible cord 13 to a catheter 17. The sensor 11 and the catheter 17 are attached to install the sensor in the cardiac wall, and thereafter are disunited and separately attached to the cardiac wall 1. The sensor is attached to the cardiac wall by claws projecting from the sensor surface, and may be installed by rotating or by deformation of the sensor.

Abstract: An electrode system for a defibrillator avoids the use of a ventricular electrode, and provides efficient utilization of the energy stored in the defibrillator with a beneficial distribution of current in the heart. The electrode system includes three electrodes, at least two of which are intravascular electrodes. One of these intravascular electrodes is placed in the inferior vena cava and the other is placed in the coronary sinus, including its continuation (the great cardiac vein) along the base of the heart. The third electrode can be either an extravascular patch electrode, located in the region of the left ventricle, or an additional intravascular electrode located in the superior vena cava. The intravascular electrodes are devised so that they do not impede the flow of blood in the vein in which they are located.

Abstract: A cardiovascular electrode catheter for use in arrhythmia ablation procedures has a dumbbell-shaped large-tip electrode having an annular recess or indentation. The annular recess divides the electrode into a ball-shaped distal portion and a generally cylindrical proximal portion. Both the distal and proximal portions of the electrode have a diameter substantially the same as that of the catheter body. The recess enables the electrode to grip the mitral or tricuspid annulus or the atrial or ventricular myocardial wall to improve ablation procedures.

Abstract: A defibrillation electrode, especially for implantation at an intravascular site in a patient, has a flexible electrode cable containing at least one elongate, electrically insulated conductor with an electrode head disposed at a distal end of the electrode cable, and having at least one defibrillation surface for delivering defibrillation pulses to the patient's heart. The electrode head is constructed so as to be radially expandable and, in an expanded position, defines the contours (surface configuration) of a hollow body so as to provide a defibrillation electrode which is affixable to the vessel in which it is sited, and which has a minimal impact on the flow of blood in that blood vessel.

Abstract: An intravenous lead for use with a cardiac device implantable beneath the skin of a patient provides positive fixation for the lead when implanted in an artery or vein of the heart. The lead includes a lead body adapted to be fed into an artery or a vein of the heart of a patient and at least one electrode carried by the lead body and adapted to be coupled to the implantable cardiac device. The lead body includes a preformed section having a resiliently coiled configuration. The coiled section makes substantially continuous surface contact with inner wall surfaces of the artery or vein after the lead is implanted within the artery or vein for providing positive fixation of the lead.

Abstract: An extractable cardiac probe comprising a catheter (4) and a sleeve (3) that is at least partially deformable and mountable to the catheter. The procedure for application of the extractable probe uses an extractor device (11) equipped to pass between the sleeve and catheter to deform the sleeve (3) elastically to permit removal and replacement of the catheter.

Abstract: A catheter with a retractable anchor mechanism for providing drugs and/or electrical stimulation to the human body. The catheter has a flexible tubular casing consisting of a outer member and an inner member which enclose at least one lumen. The retractable anchor mechanism is located near the distal end of the catheter and is moveable from a first extended position to a second retracted position. A capture member is connected to the anchor mechanism. The capture member has a socket portion and a necked down portion for guiding the enlarged tip of a stylet into the socket portion for releasable engagement therewith. The anchor mechanism is moved from the first extended position to the second retracted position by inserting a stylet and applying pressure in the distal direction and is moved from the second retracted position to the first extended position by partially withdrawing the stylet thereby applying pressure in the proximal direction.

Abstract: An electrode arrangement for in vivo stimulation of tissue with electrical energy has a catheter containing an electrical lead, the lead and the catheter being electrically and mechanically connected to further electrical conductors, arranged in a configuration forming a broad, flat, thin and flexible electrode. The conductors in the electrode are partially exposed and define an electrode surface for delivering electrical energy to adjacent tissue. The electrode arrangement further includes a fixing device, for attaching the electrode to tissue surrounding the tissue to be stimulated. The fixing device includes a fixing element which is mounted on the electrode so as to be movable independently of the electrode, and a stylet which controls movement of the fixing element, the stylet extending through the catheter. The fixing element can be controlled so as to be advanced from a retracted position to a position extending beyond the electrode surface in which the fixing element penetrates the tissue.

Abstract: The present invention provides a system and method for implanting electric leads in the pericardial space of a heart. The system includes a suction cup mounted to the distal end of a guiding catheter. A vacuum pump evacuates the guiding catheter whereby the suction cup is held against the pericardium. An endoscope fitted through the guiding catheter is used to observe the surface of the pericardium. A needle selectively deployable from the end of a flexible wire guide is fitted through the guiding catheter and cuts an access hole through the pericardium into the pericardial space. The distal tip of the wire guide is deflected into a "J" shape to anchor the wire guide in the pericardial space. A dilator having a blunt, tapered end and a longitudinal bore slides over the wire guide and is advanced to the pericardial space to dilate the access hole. A flexible sheath slides over the dilator to form a channel when the dilator is withdrawn from the wire guide.

Abstract: An improved implantable pacer lead separates the pacing function and sensing function to the benefit of both pacing threshold and sensing effectiveness. Such separation permits the reduction of the size of the necrotic capsule that forms around the pacing electrode and also permits the use of smaller pacing electrodes which stimulate smaller regions, and therefore require less energy. The separation also permits the use of materials that concentrate the pacing energy where it is needed. The separation further works to the benefit of the sensing function because the sensing electrode may be placed exactly where it is most effective, independent of the optimal pacing electrode position. Similarly the size, shape, material and surface characteristics of the sensing electrode may be optimized irrespective of the pacing electrode.

Abstract: A lead for delivering electrical stimulation pulses to pace the cardiac muscle and for sensing electrical signals occurring in the cardiac muscle is disclosed which as a rigid helix disposed at the extreme distal end thereof which rigid helix may be operated by the implanting physical to extend the tip of the rigid helix from a stored position within the distal end of the lead to a deployed position projecting from the distal end of the lead. The rigid helix pierces and engages the heart tissue to anchor the lead in place within the heart. The tip of the rigid helix has an axial bore therein which is filled with a therapeutic medication such as a steroid or steroid-based drug for inhibiting inflammation and promoting tissue growth. After the tip of the helical screw is disposed in the heart tissue, the therapeutic medication will be slowly eluted into the surrounding tissue, thereby minimizing the trauma of implantation and assisting in the anchoring of the lead.

Abstract: A method of killing microorganisms which form a biofilm on a tissue or implant surfaces in a patient, and which are refractory to a biocide at a dose which is effective to kill the microorganism in planktonic form. The effect of the biocide is potentiated, to an effective killing level, by applying an electric field across the surface containing the biofilm.

Abstract: A myocardial pacing lead includes two sets of at least two tines placed to oppose each other. The lead is pressed against the epicardium and is rotated until a rough porous tip abrades the epicardium and allows the tip and the first row of tines to penetrate the myocardium. Excessive penetration and lead migration is prevented by the second row of tines which is mounted backward and just proximal from the first row of tines. The first row of tines anchor on the inside surface of the epicardium which prevents dislodgment. Dacron pads on the second row of tines assures chronic fixation by adhering to the outer surface of the patient's epicardium.

Abstract: Endocardial mapping and/or ablation system for introduction into a chamber of the heart formed by a wall by passage through a lumen leading to the chamber in the heart having blood therein comprising a catheter probe with proximal and distal extremities and having an elongate tubular member with at least one lumen extending therethrough extending the length thereof and with a distal extremity. A plurality of longitudinally and radially spaced apart electrodes are provided. An expandable device is secured to the distal extremity of the flexible elongate tubular member and is movable between a contracted position and an expanded position. The electrodes are mounted on the expandable device whereby when the expandable device is moved to the expanded position in a chamber of the heart the electrodes are moved into engagement with the wall forming the chamber of the heart in which the expandable device is disposed.

Abstract: A method for placing various types of catheters into the pericardial space takes advantage of the fact that the right auricle is a thin-walled, low-pressure structure which can be readily penetrated without damaging the pericardium or the epicardium. The method avoids surgical trauma and the risks of general anesthesia and infection. A catheter is guided downstream through one of the venae cavae to the right atrium. Once inside the right atrium, the catheter is passed into the right auricle. The wall at the apex of the right auricle is then pierced to gain access to the pericardial space. The method can be used, for example, to provide electrical stimuli to the heart (e.g., for pacing, cardioversion, and defibrillation), to pick-up an ECG signal, to deliver pharmacologic agents to the heart, to improve vascularization, to remove pericardial fluid for analysis or pericardiocentesis, or to inject a radio-labelled or echo-sensitive dye into the pericardial space for precision fluid imaging.

Abstract: A system for myocardial tensiometry is incorporated within an implantable electrotherapy apparatus to measure contractions of the heart muscle. The system includes a tensiometric element disposed at a location subject to bending due to cardiac contractions, the tensiometric element consisting either of piezoelectric material or variable resistivity material, the mechanical stresses to which the tensiometric element is subjected causing the element to produce a voltage or a resistivity variation comparable in frequency and amplitude to the contractions. The tensiometric element may be in the form of a strip disposed on a surface of a patch electrode, of the type suitable for use in an implantable defibrillator, or may be a strip or a tube located at the bend of a J-shaped pacing lead, of the type implantable in the atrium or in the ventricle in a cardiac pacemaker system.

Abstract: An improved locking cap for mounting on the smooth flexible filament of a surgical fastener wherein the locking cap is of a thin flat washer-like shape with gripping elements for engaging the filament and locking the cap in position relative to the filament.