Abstract: The invention relates to a device for detecting atrial fibrillation of a subject, comprising a member comprising —mechanical connection means to wearably connect the member to a subject; —the member further comprising an optical sensor arranged to measure a signal representing a blood perfusion parameter of the subject; the member comprising the optical sensor and mechanical connection means at such relative positions that when the mechanical connection means connect the member to the subject, the optica! sensor operatively faces the subject. The device is arranged to detect atrial fibrillation of the subject based on the signal measured by the optical sensor.

Abstract: Apparatus and method provide flexibility in generating a stimulation waveform to an electrode of an implantable medical device. The stimulation waveform comprises at least one stimulation pulse. The embodiment of the invention supports a generation of a stimulation pulse in which an amplitude and an electrical polarity of the stimulation pulse can be dynamically changed. The embodiment comprises a capacitor arrangement, a regulator and a switching array. The capacitor arrangement can be reconfigured with respect to an electrical reference through the switching array in order for the regulator to deliver the stimulation pulse to a pair of electrodes. In another embodiment, a plurality of stimulation waveforms are generated in which different stimulation waveforms are associated with different electrodes. With the embodiment, a plurality of regulators are connected and reconfigured to the capacitor arrangement in order that the different stimulation waveforms are generated by different regulators.

Abstract: The locus of electrically excitable tissue where action potentials are induced can be controlled using the physiological principle of electrotonus. In one embodiment, first and second pulses are applied to first and second electrodes, respectively, to generate first and second subthreshold potential areas, respectively, within the tissue. The locus within the tissue where action potentials are induced is determined by a superposition of the first and second subthreshold areas according to the physiological principle of electrotonus. In another embodiment, a two-dimensional array of electrodes are formed. The cathode may be positioned near the center of the two-dimensional array or may be left out. The first and second subthreshold areas may thereby be steered. An array of anodal rings may be used to contain the field of excitation.

Abstract: The locus of electrically excitable tissue where action potentials are induced can be controlled using the physiological principle of electrotonus. In one embodiment, first and second pulses are applied to first and second electrodes, respectively, to generate first and second subthreshold potential areas, respectively, within the tissue. The locus within the tissue where action potentials are induced is determined by a superposition of the first and second subthreshold areas according to the physiological principle of electrotonus. In another embodiment, a two-dimensional array of electrodes are formed. The cathode may be positioned near the center of the two-dimensional array or may be left out. The first and second subthreshold areas may thereby be steered. An array of anodal rings may be used to contain the field of excitation.

Abstract: Apparatus and method provide flexibility in generating a stimulation waveform to an electrode of an Implantable Neuro Stimulator (INS). The stimulation waveform is synthesized for each rate period interval. Each rate period interval is partitioned into time intervals, during which stimulation pulses, recharging, and time duration delays may be induced. With the embodiment of the invention, a second stimulation pulse, having different electrical characteristics than a first stimulation pulse, may be generated during the rate period interval. An embodiment utilizes apparatus comprising a waveform controller and a waveform generator that are controlled by the waveform controller. The waveform controller uses waveform parameters to instruct the waveform generator to form stimulation pulses. Any of the components may be adjusted or deleted in the generation of the stimulation waveform.

Abstract: Apparatus and method for independently delivering a plurality of therapy programs in an implantable medical device. A therapy controller configures the device to generate independent pulse trains associated with a plurality of therapy programs and dynamically configures the electrodes to deliver the independent pulse trains to the patient. Once configured, the implantable medical device delivers the plurality of therapy programs to the patient wherein the therapy programs may overlap in time.

Abstract: Apparatus and method provide flexibility in generating a stimulation waveform to an electrode of an Implantable Neuro Stimulator (INS). The stimulation waveform is synthesized for each rate period interval. Each rate period interval is partitioned into time intervals, during which stimulation pulses, recharging, and time duration delays may be induced. With the embodiment of the invention, a second stimulation pulse, having different electrical characteristics than a first stimulation pulse, may be generated during the rate period interval. An embodiment utilizes apparatus comprising a waveform controller and a waveform generator that are controlled by the waveform controller. The waveform controller uses waveform parameters to instruct the waveform generator to form stimulation pulses. Any of the components may be adjusted or deleted in the generation of the stimulation waveform.

Abstract: Apparatus and method provide flexibility in generating a stimulation waveform to an electrode of an implantable medical device. The stimulation waveform comprises at least one stimulation pulse. The embodiment of the invention supports a generation of a stimulation pulse in which an amplitude and an electrical polarity of the stimulation pulse can be dynamically changed. The embodiment comprises a capacitor arrangement, a regulator and a switching array. The capacitor arrangement can be reconfigured with respect to an electrical reference through the switching array in order for the regulator to deliver the stimulation pulse to a pair of electrodes. In another embodiment, a plurality of stimulation waveforms are generated in which different stimulation waveforms are associated with different electrodes. With the embodiment, a plurality of regulators are connected and reconfigured to the capacitor arrangement in order that the different stimulation waveforms are generated by different regulators.

Abstract: In general, the invention is directed to an IMD having a piezoelectric transformer to power a lead-based sensor. The IMD powers the piezoelectric transformer with a low amplitude signal. The piezoelectric transformer serves to convert the voltage level of the low amplitude signal to a higher voltage level to drive the sensor produced by a battery in the IMD to voltage levels appropriate for IMD operation. A piezoelectric transformer offers small size and low profile, as well as operational efficiency, and permits the IMD to transmit a low amplitude signal to a remote sensor deployed within an implantable lead. In addition, the piezoelectric transformer provides electrical isolation that reduces electromagnetic interference among different sensors.

Abstract: An implantable medical device includes a control circuit for controlling the operation of the device and for obtaining physiological data from a patient in which the medical device is implanted. The implanted device also includes a communication circuit for transmitting the physiological data to an external device. A first power source is coupled to the control circuit and provides power to the control circuit. A second power source is coupled to the communication circuit and provides power to the communication circuit.

Abstract: The locus of electrically excitable tissue where action potentials are induced can be controlled using the physiological principle of electrotonus. In one embodiment, first and second pulses are applied to first and second electrodes, respectively, to generate first and second subthreshold potential areas, respectively, within the tissue. The locus within the tissue where action potentials are induced is determined by a superposition of the first and second subthreshold areas according to the physiological principle of electrotonus. In another embodiment, a two-dimensional array of electrodes are formed. The cathode may be positioned near the center of the two-dimensional array or may be left out. The first and second subthreshold areas may thereby be steered. An array of anodal rings may be used to contain the field of excitation.

Abstract: Apparatus and method for independently delivering a plurality of therapy programs in an implantable medical device. A therapy controller configures the device to generate independent pulse trains associated with a plurality of therapy programs and dynamically configures the electrodes to deliver the independent pulse trains to the patient. Once configured, the implantable medical device delivers the plurality of therapy programs to the patient wherein the therapy programs may overlap in time.

Abstract: Apparatus and method for independently delivering a plurality of therapy programs in an implantable medical device. A therapy controller configures the device to generate independent pulse trains associated with a plurality of therapy programs and dynamically configures the electrodes to deliver the independent pulse trains to the patient. Once configured, the implantable medical device delivers the plurality of therapy programs to the patient wherein the therapy programs may overlap in time.

Abstract: In general, the invention is directed to an IMD having a piezoelectric transformer to power a lead-based sensor. The IMD powers the piezoelectric transformer with a low amplitude signal. The piezoelectric transformer serves to convert the voltage level of the low amplitude signal to a higher voltage level to drive the sensor produced by a battery in the IMD to voltage levels appropriate for IMD operation. A piezoelectric transformer offers small size and low profile, as well as operational efficiency, and permits the IMD to transmit a low amplitude signal to a remote sensor deployed within an implantable lead. In addition, the piezoelectric transformer provides electrical isolation that reduces electromagnetic interference among different sensors.

Abstract: In general, the invention is directed to an IMD having a piezoelectric transformer to convert battery power to operating power. The piezoelectric transformer serves to convert voltage levels produced by a battery in the IMD to voltage levels appropriate for IMD operation. In contrast to electromagnetic transformers and charge pump arrays, a piezoelectric transformer offers small size and low profile, as well as operational efficiency. In addition, in an implantable cardiac or neurostimulation device, the piezoelectric transformer provides electrical isolation that avoids circuit-induced cross currents between different electrodes.

Abstract: A pacing system and method for providing multiple chamber pacing of a patient's heart, and in particular, pacing programmed for treatment of various forms of heart failure. The system utilizes impedance sensing for determining optimum pacing parameters, e.g., for pacing the left ventricle so that left heart output is maximized. The impedance sensing also is used for determination of arrhythmias or progression of heart failure. Impedance sensing is provided for between selected pairs of the four chambers, to enable optimizing of information for control and diagnosis. In a preferred embodiment of the invention, impedance measurements are obtained for determining the timing of right heart valve closure or right ventricular contractions, and the timing of delivery of left ventricular pace pulses is adjusted so as to optimally synchronize left ventricular pacing with the right ventricular contractions.

Abstract: Apparatus and method provide flexibility in generating a stimulation waveform to an electrode of an implantable medical device. The stimulation waveform comprises at least one stimulation pulse. The embodiment of the invention supports a generation of a stimulation pulse in which an amplitude and an electrical polarity of the stimulation pulse can be dynamically changed. The embodiment comprises a capacitor arrangement, a regulator and a switching array. The capacitor arrangement can be reconfigured with respect to an electrical reference through the switching array in order for the regulator to deliver the stimulation pulse to a pair of electrodes. In another embodiment, a plurality of stimulation waveforms are generated in which different stimulation waveforms are associated with different electrodes. With the embodiment, a plurality of regulators are connected and reconfigured to the capacitor arrangement in order that the different stimulation waveforms are generated by different regulators.

Abstract: Apparatus and method provide flexibility in generating a stimulation waveform to an electrode of an Implantable Neuro Stimulator (INS). The stimulation waveform is synthesized for each rate period interval. Each rate period interval is partitioned into time intervals, during which stimulation pulses, recharging, and time duration delays may be induced. With the embodiment of the invention, a second stimulation pulse, having different electrical characteristics than a first stimulation pulse, may be generated during the rate period interval. An embodiment utilizes apparatus comprising a waveform controller and a waveform generator that are controlled by the waveform controller. The waveform controller uses waveform parameters to instruct the waveform generator to form stimulation pulses. Any of the components may be adjusted or deleted in the generation of the stimulation waveform.

Abstract: Apparatus and method for independently delivering a plurality of therapy programs in an implantable medical device. A therapy controller configures the device to generate independent pulse trains associated with a plurality of therapy programs and dynamically configures the electrodes to deliver the independent pulse trains to the patient. Once configured, the implantable medical device delivers the plurality of therapy programs to the patient wherein the therapy programs may overlap in time.

Abstract: In the embodiment of the invention, apparatus and method provide flexibility in generating a stimulation waveform to an electrode of an Implantable Neurological Stimulator (INS). The embodiment provides a time delay interval between a first stimulation pulse and a recharging of the apparatus, in which the time delay interval is adjustable. The embodiment utilizes apparatus comprising a waveform controller and a waveform generator that is controlled by the waveform controller. With a variation of the embodiment, the apparatus utilizes passive recharging. In another variation of the embodiment, the apparatus utilizes a second stimulation to balance an accumulated charge. In another embodiment of the invention, a clinician is able to adjust the time delay interval through a telemetry channel. The waveform controller receives information about the time delay interval, and the waveform control instructs the waveform generator to adjust the time delay interval.