Abstract: A bi-polar cardiac lead for transmitting electric current to the heart and/or sensing and monitoring electrical activity of the heart has elongated electrical conductors connected to a head. The lead has a first electrode mounted on the head having a helical wire connected to one conductor adapted to be turned into heart tissue. The helical wire is coated with platinum black particles which decrease electrical losses at the electrode-tissue interface. A second annular electrode having an irregular outer surface configuration is mounted on the head around the first electrode. A plug impregnated with a drug is located within a recess in the head adjacent the electrodes. The drug migrates from the plug to the stimulation site.

Abstract: A cardiac lead has an electrode and fixation assembly including a plurality of fixation members movable to extended positions into heart tissue to retain the electrode in intimate engagement with heart tissue. An elongated stylet is used to move the fixation members to their extended positions into the heart tissue and retract the fixation members into the fixation assembly to allow the lead to be removed from the heart and body of a person.

Abstract: A cardiac lead for transmitting electric current to the heart and/or sensing and monitoring electrical activity of the heart has an elongated electrical conductor connected to a head. An electrode mounted on the head comprises a helical wire adapted to be turned into heart tissue. A second electrode having an irregular or non-flat surface surrounds the helical wire. The non-flat surface may be a wire mesh, a segmented plate and an annular plate supporting one or more coiled wires.

Abstract: A tool for implanting a pacing lead into heart tissue has a pair of side-by-side beams pivoted together at the opposite ends thereof. The beams have jaws that grip a lead head supporting a helical electrode and a groove for accommodating a section of the lead extended from the head. A releasable lock interposed between the beams operates to hold the beams in jaw closed position to grip the head of the electrode. the lock has flexible fingers and a movable sleeve that allows one hand operation to selectively lock and release of the jaws. The helical electrode has an external layer of platinum black particles resulting in decreased electrical losses at the electrode-tissue interface, increased current density, lower stimulation thresholds, and increased amplitude of sensed electrical signals from the heart tissue.

Abstract: A tool for implanting a pacing lead into heart tissue has a pair of side-by-side beams pivoted together at the opposite ends thereof. The beams have jaws that grip a lead head supporting a helical electrode and a groove for accommodating a section of the lead extended from the head. A releasable lock interposed between the beams operates to hold the beams in jaw closed position to grip the head of the electrode. The lock has flexible fingers and a movable sleeve that allows one hand operation to selectively lock and release of the jaws. The helical electrode has an external layer of platinum black particles resulting in decreased electrical losses at the electrode-tissue interface, increased current density, lower stimulation thresholds, and increased amplitude of sensed electrical signals from the heart tissue.

Abstract: A structure for use as an electrode on a pacing lead to be located some distance proximal to the distal end of the pacing lead. Two short lengths of wire having high electrical conductivity are cut to size. The coils of the outer conductor are welded together at the desired location of the ring electrode of the lead. The two short lengths of wire are welded to the outer conductor of the lead at the desired location of the ring electrode. An insulating sheath having an inside diameter close to the outside diameter of the outer conductor is slid over the outer conductor. The flexibility of the insulating sheath is sufficient to permit encasing of the two short lengths of wire, though the insulating sheath is caused to protrude at the two places directly over and corresponding to the two short lengths of wire.

Abstract: A body implantable lead having a two-piece stylet. An inner solid portion of the stylet enables a shape to be imparted to the stylet to allow proper maneuvering of the lead during implant. A second portion of the stylet is slideably located coaxially about the first portion. The second portion of the stylet permits the imposition of a torque at the distal end of the implantable lead by the turning of a knob fixedly attached to the proximal end of the second portion of the stylet. The second portion of the stylet is a helically wound coil. The two-piece stylet is inserted into the proximal end of the body implantable lead. The distal end of the body implantable lead is located in the position desired through the use of the solid inner first portion of the stylet in which a bend or other desired shape has been introduced. The body implantable lead is permanently attached to the muscle tissue by a fixation device activated through the torque supplied by the second portion of the stylet.

Abstract: Epicardial pacing lead for affixation to epicardial heart tissue either onto the forward facing portion of the heart or behind the heart during thoracic surgery. A stylet controls a helical fixation screw in an electrode head of the pacing lead in that the stylet is turned thereby advancing the helical fixation screw beyond the planar surface of the electrode head. The epicardial pacing lead includes two embodiments which can be used in the unipolar mode of operation and one embodiment which can be used in the bipolar or unipolar mode of operation. The epicardial pacing lead requires no special tools and can be applied to the epicardial tissue with the use of surgical forceps or clamps. The pacing lead can be connected to a pulse generator located adjacent to the epicardial tissue under the skin and can be used for atrial or ventricular pacing.

Abstract: A body implantable lead and a stiffening stylet with a flexible tip for imparting rigidity to the lead to facilitate attachment of the lead to an internal body organ and for transmitting torque to the distal end of the lead. A flexible tip stiffening stylet is provided for insertion into a lumen in the lead extending from a pin at its proximal end along the length of the lead conductor to the electrode. A portion of the stylet wire inserted in the lumen has a thinner diameter over a portion of its length near the distal end to permit smooth transmission of torque by rotation of the stylet wire even in applications where the lead and stylet are tightly bent in the vicinity of the thinned portion of the lead.

Abstract: The lead anchoring bobbin for containing a transvenous pacing lead at an entry site in human tissue and including a grooved bobbin and buttons which frictionally engage and detain the lead on either side of the bobbin. The lead anchoring bobbin is made of medical silicone rubber or like material.

Abstract: Stylet including a stylet knob, a stylet wire, and a swaged stylet wire retaining sleeve over the stylet wire which engages within the stylet knob providing for controlled length and straightness of the stylet wire and mating within the long thin walled stylet knob.

Abstract: A body-implantable, lead affixed with a pin or pins at its proximal end adapted to be connected to a pulse generator and with an electrode or electrodes at its distal end electrically connected via conductor means and adapted to be securely and permanently attached to a body organ. Electrode means in the form of an elongated member having a circumferential electrode formed on one end thereof and an opening passing therethrough from its proximal to distal end is affixed to the distal end of the conductor means. Tissue securing means are located within a chamber beyond the opening of the electrode body to protect body tissue while the lead is being moved to the desired location. The tissue securing means is then extendable out of the distal end of the electrode means to secure the electrode means in firm engagement with body tissue at the desired location.

Abstract: A body implantable lead and a stiffening stylet with a flexible tip for imparting rigidity to the lead to facilitate attachment of the lead to an internal body organ and for transmitting torque to the distal end of the lead. A flexible tip stiffening stylet is provided for insertion into a lumen in the lead extending from a pin at its proximal end along the length of the lead conductor to the electrode. At the proximal end of the stylet, a guide and rotation control device is provided to aid in insertion of the lead and stylet and to facilitate rotation of the stylet to permanently attach the electrode at the distal end to a body organ through endothelial tissue.

Abstract: A body-implantable, intravascular lead affixed with a pin or pins at its proximal end adapted to be connected to a pulse generator and with an electrode or electrodes at its distal end electrically connected via conductor means and adapted to be securely and permanently attached to a body organ. Electrode means in the form of an elongated member having a circumferential electrode formed on one end thereof and an opening passing therethrough from its proximal to distal end is affixed to the distal end of the conductor means. Tissue securing means extending beyond the opening in the distal end of the electrode means are provided for securing the electrode means into firm engagement with the tissue at the desired location. Movable means located in the opening in the electrode means are provided for protecting the tissue securing means from causing injury to a body vessel, heart valve, or other tissue as the lead is inserted and guided through a vessel to the desired location.

Abstract: Apparatus for stimulating body tissue and in particular the heart, is disclosed as including a device or circuit responsive to the initiation of stimulation and/or to the failure or pending failure of a component of the stimulating apparatus to provide the patient with a perceivable stimulation to a second, different portion of body tissue. There is disclosed an impedance level detector for sensing the impedance presented between the outputs of the stimulation apparatus to provide a warning signal indicating that the output impedance falls outside a predetermined range. In particular, the impedance level detector output is sensed by a stimulation control logic to apply a first train of pulses at a first rate to an auxiliary electrode for stimulating the second portion of tissue.

Abstract: A body implantable, intravascular lead affixed with a pin or pins at its proximal end adapted to be connected to a pulse generator and with an electrode or electrodes at its distal end adapted to be placed in contact with the endocardium. An electrical conductor(s) encased within a nonconductive material substantially inert to body fluids and tissues electrically connects the electrode(s) with the pin(s) and is comprised of a first length of resilient conductor having a first flexibility and an axial mechanical loading characteristic and a second length of the conductor having a second flexibility greater than the first flexibility and incapable of sustaining the axial mechanical loading characteristic. A dumbbell shaped electrode body provides sufficient size and weight to maintain the distal end of the lead in the apex of the right ventricle.

Abstract: A body implantable lead having a two-piece stylet. An inner solid portion of the stylet enables a shape to be imparted to the stylet to allow proper maneuvering of the lead during implant. A second portion of the stylet is slideably located coaxially about the first portion. The second portion of the stylet permits the imposition of a torque at the distal end of the implantable lead by the turning of a knob fixedly attached to the proximal end of the second portion of the stylet. The second portion of the stylet is a helically wound coil. The two-piece stylet is inserted into the proximal end of the body implantable lead. The distal end of the body implantable lead is located in the position desired through the use of the solid inner first portion of the stylet in which a bend or other desired shape has been introduced. The body implantable lead is permanently attached to the muscle tissue by a fixation device activated through the torque supplied by the second portion of the stylet.