Abstract: Heart stimulator that provides for timing a premature stimulation pulse for anti-tachycardia pacing outside the vulnerable phase of a ventricle, to terminate stable ventricular tachycardia while minimizing the risk of accelerating stable ventricular tachycardia into unstable ventricular tachycardia or ventricular fibrillation. RT interval is determined instead of QT interval. Conventional QT interval is defined to end at T wave offset, which is difficult to measure because inherent imprecision in identifying the end of T wave from surface ECG. For safe ATP, such problems may be avoided. Because the VP usually refers to the portion of the T wave near the peak and early downslope (FIG. 3), in order to avoid the VP, only need to determine the peak of T wave, then set an blanking window or safety margin (e.g., 20 ms before to 20 ms after the peak of T wave) during which ATP pulses should not be delivered.

Abstract: The invention is directed to a heart stimulator for left-ventricular pacing comprising a left ventricular stimulation pulse generator connected or connectable to a single electrode lead for left ventricular stimulation having one or more electrodes for delivery of stimulation pulses to left ventricular myocardial heart tissue, said stimulation pulse generator being adapted to generate and deliver stimulation pulses of switchable polarity. The heart stimulator further comprises a control unit connected to the stimulation pulse generator for controlling the stimulation pulse generator and to trigger generation and delivery of stimulation pulses having a polarity controlled by said control unit, wherein the control unit is adapted to control said left ventricular stimulation pulse generator so as to deliver at least a pair of suprathreshold stimulation pulses of opposite polarity.

Abstract: A medical device and a method is suggested for assessing the risk of R on T events. The device comprises a memory, input means for acquiring or receiving an electrogram signal and processing means. The processing means are adapted to detect R-wave and T-waves represented by said electrogram, establish a QT-RR regression model based detected R-waves and T-waves, estimate a vulnerable period, and store estimated vulnerable period data in said memory. Likewise, the method comprises the steps of to detecting R-wave and T-waves represented by an electrogram, establishing a QT-RR regression model based detected R-waves and T-waves, estimating a vulnerable period, and storing estimated vulnerable period data.

Abstract: A switching device for direct-current applications includes a housing having a first wall and a second wall, a plurality of receiving areas for respective mutually substantially parallel current paths disposed in the housing. Each of the current paths has a respective stationary switching contact element and a respective movable switching contact element, the movable switching element being actuatable into a closed position and into an open position so as to form a respective air break, the respective movable switching contact elements being actuatable simultaneously. The switching device includes a plurality of arc-quenching devices associated with the current paths and disposed next to each other, and at least one magnet. The at least one magnet is configured to generate a magnetic field so as to generate a deflection force on the arcs so as to deflect the respective arcs toward at least one of the respective arc-quenching devices.

Abstract: A switching device for direct-current applications including a housing, and at least three current paths. Each current path includes a respective movable switching contact element, a respective stationary switching contact element, and a respective air break between the respective movable and stationary contact elements. Each movable switching contact element is movable into a closed position and into an open position. The switching device includes a quenching capacitor connected in parallel to the respective at least one air break of a first of the current paths and configured to at least one of prevent the formation of an arc and quench an arc formed therealong. The quenching capacitor is not coupled to a second of the current paths. The second current path is couplable in series to the first current path.

Abstract: An implantable cardiac stimulator (10), configured to switch mode of operation between at least one right ventricular stimulation mode in which no control signals triggering left ventricular stimulation pulses are delivered to the left ventricular stimulation unit and a biventricular stimulation mode in alternation. Switching takes place as a function of duration of prevailing QRS signal interval, such that the cardiac stimulator switches to biventricular stimulation mode when comparison of the duration of a prevailing QRS signal interval with a first comparison value reveals the duration of the prevailing QRS signal interval is longer than a first reference value represented by the first comparison value and switches to right ventricular stimulation mode when comparison of the duration of a prevailing QRS signal interval with a second comparison value reveals the duration of the prevailing QRS signal interval is shorter than a second reference value represented by the second comparison value.

Abstract: An implantable cardiac device is provided for adaptive ventricular rate smoothing during atrial fibrillation (AF). When AF is detected, the operation of the device is switched to non-atrial synchronized pacing mode such as DDI, DDIR, VDI, VDIR, VVI, or VVIR. The ventricular escape interval (VEI) is beat-by-beat modulated around a physiological interval zone (PIZ), which is determined by the pre-arrhythmia ventricular rate or the output of rate responsive sensor. The VEI remains unchanged if the preceding ventricular event is sensed and its RR interval is within the PIZ. Otherwise, the VEI is decreased asymptotically toward a lower interval threshold if the preceding RR interval is longer than the upper limit of the PIZ, or the VEI is increased asymptotically toward an upper interval threshold if the preceding RR interval is shorter than the upper limit of the PIZ.

Abstract: An atrial defibrillator has a stimulation pulse generator to generate pacing pulses, a sensing stage for sensing intrinsic ventricular events, (an R-wave having an amplitude). It also includes a defibrillation shock generator to generate an atrial defibrillation shock, an atrial fibrillation detector adapted to detect an atrial fibrillation, and a control unit connected to the stimulation pulse generator. The sensing stage, the atrial fibrillation detector, the defibrillation shock generator, and control unit are adapted to trigger an atrial defibrillation shock after detection of an atrial fibrillation and synchronous with a sensed or a paced ventricular event. The control unit is adapted to compare a sensed R-wave amplitude with a reference R-wave amplitude and synchronize an atrial defibrillation shock with a paced ventricular event or a sensed ventricular event if the sensed ventricular event is an R-wave having an amplitude of at least 60% of the magnitude of the reference amplitude.

Abstract: An implantable medical device that continuously measures the patient's intracardiac ventricular impedance. Extracts cardiac performance information based on the intracardiac impedance, including amplitude, timing and variability of cardiac contraction function. The device records and analyses trends in the performance information. The device identifies changes, which exceed the selected threshold limits. In the event of an incipient crisis, the device transmits an alert message.

Abstract: Heart monitoring system includes implantable medical device and service center.

Abstract: An implantable device system comprising an implantable medical device, an external transceiver device and a service center. The implantable medical device comprises a battery and an electronic module including a stimulation pulse generator, a sensing stage, a control unit adapted to collect data representing values of operational parameters (e.g. peak or average current consumption, high/low/average voltage level) of the battery and the electronics. The external transceiver device comprises an external transceiver unit and a data communication interface and the service center comprises another data communication interface adapted to allow data communication with the external transceiver device.

Abstract: A medical device having a sensor for sampling a biological signal, the biological signal representing a signal waveform and forming a waveform vector composed of the biological signal samples, and a memory for storing a least two threshold vectors composed of boundary samples representing at least two boundaries related to the biological signal defining subspaces for the biological signal samples. One threshold vector is an upper threshold vector composed of upper boundary samples and the other threshold vector is a lower threshold vector composed of lower boundary samples. An evaluation unit connected to the sensor determines a similarity index (ASCI) by comparing each of the biological signal samples of the waveform vector to corresponding boundary samples of the threshold vectors, thus determining to which subspace each biological signal sample belongs to and creating a trichotomized signal vector, and calculating the signed correlation product of two trichotomized signal vectors.

Abstract: Heart stimulator that provides for timing a premature stimulation pulse for anti-tachycardia pacing outside the vulnerable phase of a ventricle, to terminate stable ventricular tachycardia while minimizing the risk of accelerating stable ventricular tachycardia into unstable ventricular tachycardia or ventricular fibrillation. RT interval is determined instead of QT interval. Conventional QT interval is defined to end at T wave offset, which is difficult to measure because inherent imprecision in identifying the end of T wave from surface ECG. For safe ATP, such problems may be avoided. Because the VP usually refers to the portion of the T wave near the peak and early downslope (FIG. 3), in order to avoid the VP, only need to determine the peak of T wave, then set an blanking window or safety margin (e.g., 20 ms before to 20 ms after the peak of T wave) during which ATP pulses should not be delivered.

Abstract: An implantable cardiac device includes a housing (2), pulse generator (7) therein to generate physiologically effective electrical pulses, a shock lead (3), externally of the housing (2), connectable to the pulse generator (7) and implantable into a patient's body to apply physiologically effective electrical pulses to the patient's body, a monitor (8) to automatically detect a lead condition as to whether the shock lead (3) is implanted or not, and control (9), which due to the detected lead condition automatically enables or disables the pulse generator (7).

Abstract: A biventricular heart stimulator is adapted to optimize an interventricular delay interval duration by minimizing a mechanical asynchrony between right and left ventricle. Mechanical asynchrony between right and left ventricle is determined by measuring right ventricular and left ventricular intracardiac impedance or conductivity.

Abstract: An implantable cardiac electrostimulator comprising an atrial sensing channel for processing intracardiac electrogram signals and for detecting signals corresponding to atrial activity and for generating an atrial sense event signal upon detection of a signal corresponding to atrial activity, a ventricular sensing channel for processing intracardiac electrogram signals and for detecting signals corresponding to ventricular activity and for generating a ventricular sense event signal upon detection of a signal corresponding to ventricular activity, a VES detector being operatively connected to said atrial and ventricular sensing channel and being adapted to detect ventricular extrasystoles an atrial stimulation pulse generator a ventricular stimulation pulse generator a stimulation control unit being operatively connected to said atrial stimulation pulse generator and said ventricular stimulation pulse generator.

Abstract: An atrial defibrillator has a stimulation pulse generator to generate pacing pulses, a sensing stage for sensing intrinsic ventricular events, (an R-wave having an amplitude). It also includes a defibrillation shock generator to generate an atrial defibrillation shock, an atrial fibrillation detector adapted to detect an atrial fibrillation, and a control unit connected to the stimulation pulse generator. The sensing stage, the atrial fibrillation detector, the defibrillation shock generator, and control unit are adapted to trigger an atrial defibrillation shock after detection of an atrial fibrillation and synchronous with a sensed or a paced ventricular event. The control unit is adapted to compare a sensed R-wave amplitude with a reference R-wave amplitude and synchronize an atrial defibrillation shock with a paced ventricular event or a sensed ventricular event if the sensed ventricular event is an R-wave having an amplitude of at least 60% of the magnitude of the reference amplitude.

Abstract: A medical therapy system has logic and/or signal processing stages between sensors on the input side and therapy applicators on the output side. A signal parameter is determined from the input signals using the logic/processing stages, and/or an indicator signal is determined from the input signals using a logic/processing module consisting of several logic/processing stages. The indicator signal is a measure of the probability of a future event requiring therapy, or a measure of the success of the therapy.

Abstract: The friction clutch between the prime mover and the change-speed transmission in the power train of a motor vehicle is actuatable by a slave cylinder cooperating with a master cylinder wherein the piston is movable by a clutch pedal or by an electric actuator. The casing of the slave cylinder is made, at least in part, of a plastic material and defines a plenum chamber arranged to receive pressurized fluid from the master cylinder by way of a conduit extending through a bell which contains the clutch and the slave cylinder. The annular piston of the slave cylinder surrounds the input shaft of the transmission. The plastic material of the casing of the slave cylinder can contain one or more additives which enhance its strength and/or influence its frictional engagement with the adjacent surfaces of the piston or of a lip seal which reciprocates with the piston.

Abstract: The friction clutch between the prime mover and the change-speed transmission in the power train of a motor vehicle is actuatable by a slave cylinder cooperating with a master cylinder wherein the piston is movable by a clutch pedal or by an electric actuator. The casing of the slave cylinder is made, at least in part, of a plastic material and defines a plenum chamber arranged to receive pressurized fluid from the master cylinder by way of a conduit extending through a bell which contains the clutch and the slave cylinder. The annular piston of the slave cylinder surrounds the input shaft of the transmission. The plastic material of the casing of the slave cylinder can contain one or more additives which enhance its strength and/or influence its frictional engagement with the adjacent surfaces of the piston or of a lip seal which reciprocates with the piston.