Abstract: In a method of and apparatus for deriving indices characterizing atrial arrhythmias, a temporally isolated portion of a digital representation of a time-domain electrical signal originating from the atria of a patient is frequency analyzed to provide a corresponding frequency spectrum. The obtained frequency spectrum is compared with a template frequency spectrum, selectively adapted dependent on previously obtained frequency spectra from different temporally isolated portions, to determine a frequency shift value and an amplitude value that optimize a correlation between the two spectra. An output representing the two determined values is used, possibly together with parameters describing the template frequency spectrum, to classify an atrial arrhythmia manifest in the digital representation.

Abstract: A set for installing an intracardiac lead equipped with a screw in a wall of the endocardium, particularly a stimulation or defibrillation lead. This set comprises a removable stylet (50), able to be introduced inside the sheath (12) of the lead-body and mobile in translation and rotation therein. The stylet has at its distal extremity a mechanism (56) for coupling in rotation to allow the rotation (28) of the lead-head (10). The stylet (50) includes: a central core (52, 71) carrying at its distal extremity the aforementioned coupling mechanism, and at its proximal extremity a handling body (32) for handling by the physician and a hollow tube (54) axially placed around the core.

Abstract: A multi-chamber pacing system has a pulse generator for successively delivering pacing pulses to chambers of a patient's heart, and IEGM signal detectors, having blanking intervals following the delivery of pacing pulses, including sensing circuits for sensing IEGM-signals from each of the heart chambers. Each of said sensed IEGM signals has a generally known morphology. A signal-reconstructing unit reconstructs the IEGM signal from one of the heart chambers in the blanking interval following delivery of a pacing pulse to another heart chamber.

Abstract: In a method and apparatus for determining the depleted capacity of a CFx type battery used in an implantable medical device, average values of battery voltage and battery current drawn from the battery are measured during a measurement time, the length of which exceeds a battery voltage recovery time after a load change, and wherein the actual depleted capacity of the battery is determined by predetermined relations between combinations of the average values of voltage and current and depleted battery capacity.

Abstract: The invention provides a stethoscope device comprising a chest piece, an amplifier and a mixer compatible with a conventional voice quality telephone system. Electrical signals are generated that are representative of physiological sounds such as breath sounds, heart sounds and bowel sounds. The electrical signals can be combined with voice communications at the remote site and transmitted over the telephone system. The invention also provides a system and method for diagnosis by a trained health care professional with the patient being located at a remote site. In another embodiment, the invention also provides a system and method for training students to interpret stethoscope sounds. In addition, the system allows for simultaneous listening by the health care professional and another individual at the remote location of the stethoscope.

Abstract: To provide a positive indication that a medical lead terminal is properly secured within the longitudinal bore in the header of an implantable medical device there is provided a force sensor (strain gauge) positioned within the device's lead receiving bore and cooperating with the lock mechanism to provide an indication of the amount of force being exerted on the lead terminal to retain it in place. The force sensor provides an output signal through the device's feedthrough wires to the electronic circuit contained within a hermetically sealed housing and is compared by a microprocessor to preprogrammed values. The results of the comparison may then be telemetered to an external programmer device for analysis by a physician.

Abstract: This invention relates to a conductance path mechanism of a wireless heartbeat transmitter comprising a circuit board, a spiral spring, a U-shaped contact rod integrally molded to both side of a bottom cover and a rubber conductible sheet. A horizontal portion of said U-shaped contact rod is totally inserted inside a foundation of a bottom cover to form a steady mechanism of the present invention.

Abstract: A laminate having a plurality of layers of magnetic material sandwiched together having a first side and a second side and a method of making the laminate. The plurality of layers of magnetic material having a plurality of radial grooves. A first insulative layer applied over the first side of the plurality of layers of magnetic material. A lead wire applied to over first insulative layer at a predetermined location on the first side of the plurality of layers of magnetic material. A second insulative layer applied to the first side of the plurality of layers of magnetic material over the lead wire. A third insulative layer applied to the second side of the plurality of layers of magnetic material. Thus, the laminate is ready to receive a coil.

Abstract: A method and device for reducing signal drift on a balloon catheter mounted pressure sensor by adjusting for signal gain and/or zero offset, and by separately calibrating the constant signal component and the time-varying signal component of an uncalibrated source signal to produce a calibrated source signal.

Abstract: A connector block and associated locking setscrew for an implantable electronic tissue stimulating device are designed to eliminate thread damage to the setscrew which is a cause of the setscrew becoming stuck in the connector block. The threaded bore in the connector that is adapted to receive the setscrew is provided with an undercut at the end of the threaded bore where the undercut provides an annular, 360-degree flat surface that is normal to the longitudinal axis of the setscrew receiving bore. The setscrew employed is designed to have a shoulder machined a predetermined distance below the terminus of the final thread by machining a reduced diameter portion on the distal end of the setscrew. Now, when the setscrew is inserted into its threaded bore, the shoulder on the setscrew and the flat surface on the undercut in the connector block meet, preventing any portion of the screw threads from extending beyond the internal threads formed in the setscrew receiving bore of the connector block.