Abstract: A circuit and method for detecting cardiac rhythm abnormalities employ unipolar signals respectively obtained from a cardiac lead having a tip at which a number of separate electrodes are disposed, the electrodes being simultaneously in contact with cardiac tissue. The respective unipolar signals which are obtained from the multiple electrodes exhibit a time relationship relative to each other, and this time relationship is analyzed to determine whether a cardiac rhythm abnormality is present or one or more of the unipolar signals is compared to a template which is known to represent a cardiac abnormality. Analysis of the time relation is undertaken by determining the absolute value of a time offset between any two of the unipolar signals, or by correlating any two of the unipolar signals.

Abstract: In am method for coating a tip region of an multipolar electrode head adapted to be mounted at a distal end of a lead used preferably for providing heart stimulation by means of a heart stimulation apparatus, an electrode head is provided having a tip with a ceramic part in which a number of small spaced-apart conductive electrode surfaces are disposed, a region of the electrode head tip is directly coated with a tissue compatible material, such as TiN, so that all conductive electrode surfaces are coated in a single step coating operation without any masking operation.

Abstract: A circuit and method for detecting cardiac rhythm abnormalities employ unipolar signals respectively obtained from a cardiac lead having a tip at which a number of separate electrodes are disposed, the electrodes being simultaneously in contact with cardiac tissue. The respective unipolar signals which are obtained from the multiple electrodes exhibit a time relationship relative to each other, and this time relationship is analyzed to determine whether a cardiac rhythm abnormality is present or one or more of the unipolar signals is compared to a template which is known to represent a cardiac abnormality. Analysis of the time relation is undertaken by determining the absolute value of a time offset between any two of the unipolar signals, or by correlating any two of the unipolar signals.

Abstract: In am method for coating a tip region of an multipolar electrode head adapted to be mounted at a distal end of a lead used preferably for providing heart stimulation by means of a heart stimulation apparatus, an electrode head is provided having a tip with a ceramic part in which a number of small spaced-apart conductive electrode surfaces are disposed, a region of the electrode head tip is directly coated with a tissue compatible material, such as TiN, so that all conductive electrode surfaces are coated in a single step coating operation without any masking operation.

Abstract: An implantable electrode lead has a proximal end intended for connection to, e.g., a pacemaker and has a distal end with an electrode head equipped with an external, tine-type anchoring unit. The anchoring unit has a number of projections which are integrally formed as a one-piece unit together with a ring-shaped carrier. The carrier is made of an elastic material, and is disposed under elastic tension in an annular groove in the exterior of the electrode head, which fixes the position of the anchoring unit relative to the electrode head. The anchoring unit detaches from the electrode head, by the carrier being pulled out of the groove, when a predetermined, minimum pulling force is exerted on the electrode head from the proximal end of the lead.

Abstract: A device for preventing an anchoring element disposed at the distal end of an implantable electrode cable from coming into contact, during introduction of the cable into a body cavity, with a cavity wall and thereby damaging the cavity wall, as a protection element which either projects beyond the distal tip of the helical anchoring element, or has the distal tip of the helical anchoring element embedded therein. The protection element is composed of a porous, resilient, spongy material which is compressible. The protection element has interstices which are at least partially filled with medication, and the protection element is compressible during affixing of the anchoring element in the heart wall, so as to express the medication from the interstices.

Abstract: A connector assembly for an implantable medical device such as a heart stimulator having a hermetically sealed enclosure containing electrical circuits and a power source, is affixed to the enclosure of the stimulator or is incorporated therein for producing an electrical connection between a proximal end of an electrical cable and the circuits in the enclosure. The connector assembly has a first connector in the form of a female connector part with the electrical contacts embedded in a puncturable membrane disposed inside of the connector assembly. The first connector is placed in electrical contact with a second connector which is arranged on a male connector part on the proximal end of the electrode cable.

Abstract: An electrical female connector for affixing a contact pin of an electrode cable in a connector part of a heart stimulator has a sleeve which is elastic and which has a curved shape in a relaxed condition. The sleeve is straightened to a substantially straight configuration when the contact pin is inserted into the sleeve, and thereupon rebounds back to a partially curved configuration so as to clamp the contact pin inside the sleeve.

Abstract: An active medical implant has a hermetically sealable capsule formed by a first part and a second closing part, the capsule being devised to hold a battery unit, an electronics unit, conductors for electrically connecting the battery to the electronics unit, and contacts arranged on the exterior of the capsule for connection to electrodes. The first part is made, at least in part, of a rolled, multi-layer composite sheet or plate, one layer of which is made of a biocompatible material and a second layer of which is made of a diffusion-proof material which is essentially resistant to corrosive chemicals. The two layers are joined by rolling, with the layer made of biocompatible material constituting the outer wall of the capsule.

Abstract: A stylet unit which can be introduced into a narrow, hollow, flexible component, such as a hollow electrode cable for a heart stimulator, to stiffen the component and bend its distal end section, is in the form of a double stylet combination with a flexible stylet shell and an internal stylet, movably arranged inside the shell, with a pre-curved distal end section, whose radius of curvature is on a first side of the stylet. In an area before the pre-curved end section, the stylet has a pre-shaped stylet section with a pre-shaped stylet section whose radius of curvature is on the side of the stylet opposite the first side on which the end section's radius of curvature lies.

Abstract: An electrode device which has a proximal end and distal end, contains of a number of thin, insulated electrical conductors each with a proximal end and a distal end, the conductors being equipped with implantable electrode contacts means which are electrically connected to the conductors. These contacts are designed to be brought into electrical contact with tissue in one or more cavities in a human body. Each conductor in the cable device is supported by a pre-shaped stiffening element which runs along and is connected to the conductor, made of an elastic polymer material, resorbable in vivo, which is biodegradable and biocompatible. The stiffening element imparts an arched shaped to the conductor, at least in the area in which its contact is located, to cause the contact to press against the adjacent cavity wall. The cable device also includes a longitudinal channel in which a stylet can be inserted for temporary, linear stretching of the cable device and the arched sections of its conductors.

Abstract: An electrode cable for implantation in a body cavity has a tube made of a biodegradable, biocompatible polymer material attached to the exterior of the cable, the tube forming a channel for a stylet.

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: 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: In a method for manufacturing electrodes for medical applications, particularly implantable stimulation electrodes, having an active layer of porous titanium nitride, a substrate of electrically conductive material that is in an atmosphere containing titanium, nitrogen and hydrogen is irradiated with an excimer laser through an optical mask, and a structure of porous titanium nitride is deposited on the substrate.

Abstract: A device for explanting an electrode device, particularly an intravascular or intracardiac electrode device having an electrode cable and an electrode head arranged on the cable's distal end, is capable of simply and safely detaching fibrotic matter from the entire surface of the electrode cable and electrode head. The explanting device has a stiff first sleeve, relatively short in relation to the length of the electrode cable, and whose diameter is slightly larger than the external diameter of the electrode cable. One end of the sleeve forms a cutting edge. The first sleeve is connected at its end opposite the cutting edge to a first control body in the form of a stylet with which the first sleeve can be moved along the implanted electrode device. A second sleeve, operable with another stylet, amy additionally be employed, having resilient cutting elements.

Abstract: A method and apparatus are disclosed for tracing leaks in vivo which occur in an electrode device, such as a pacemaker or a defibrillator, the electrode device including an electrode cable containing an elongate, flexible conductor having an exterior covered with a layer of insulation and having an interior channel. A leakage tracing device which is simple in structure, and therefore inexpensive to make, and with which one or more leaks in an electrode cable implanted in a patient is/are readily detectable, has a tubular, flexible body within an external diameter smaller than inner diameter of the interior channel of the electrode cable. The tubular body can be inserted into the electrode cable's interior channel all the way to the channel's distal end, and the proximal end of the tubular body is connected to a container for a fluid.

Abstract: An implantable medical system, having an implanted therapy-generating apparatus which administers a medical therapy in vivo to a treatment site remote from the therapy-generating apparatus, includes at least one optical conductor connected between the therapy-generating apparatus and the tissue at the treatment site, or an additional implantable medical device. Energy and/or information can be transmitted by optical signals using the optical conductor, in a safe and noise-free manner. Each location at which the optical signals are to be transmitted or received is provided with an optoelectrical converter, or an electro-optical converter, as appropriate.

Abstract: A multipolar electrode lead, of the type used to deliver electrical energy in vivo to tissue as part of a system for medical electrotherapy, contains at least first and second conductors, with at least the first conductor being provided with an insulating coating which electrically separates the conductors from each other. The risk of the insulating coating being worn off and a short-circuit developing are reduced by forming the insulating coating of a material having a high electrical resistance and a resistance to abrasion.

Abstract: A medical electrode for intracorporeal electrical stimulation of body tissue, particularly for intracardial stimulation of heart tissue, includes an electrode cable having an elongated, flexible conductor covered with insulation, and terminating at one end with an electrode head for contact with body tissue. An opposite end of the cable is connectable to a source of therapeutic electrical energy. The exterior surface of the insulation is provided with a helical element winding around a substantial portion of the length of the cable between the opposite ends. The helical element may be a thin-like projection, or a groove. A device for rotating the cable during implantation causes the cable, by virtue of the helical element, to be advanced through a vein.