摘要:
A pacemaker having two bipolar leads, one atrial, one ventricular, each with TIP and RING electrodes, configured as for conventional bipolar pacing/sensing in both chambers. Switching circuitry in the pacemaker is operable to select from among various possible sensing configurations, including one configuration in which sensing is performed between the ring electrodes of the respective pacing/sensing leads. Pacing is preferably performed in a conventional unipolar configuration in each chamber, from the respective tip electrodes. The "ring-to-ring" EGM signal is applied to filtering and EGM amplifier circuitry, and then provided to a telemetry system for transmission to an external receiver. The ring-to-ring EGM signal possesses the high resolution properties of conventional intracardiac signals, and is relatively unaffected by the after-potentials and tissue polarization effects that arise when the same lead is used for pacing and sensing. Additionally, the ring-to-ring EGM signal is a composite of atrial and ventricular electrical signals, and thus has an appearance similar to that of surface ECGS. In the disclosed embodiment, separate atrial and ventricular EGM amplifiers are provided, with the atrial EGM amplifier receiving a conventional atrial unipolar sensing signal and the ventricular EGM amplifier receiving a conventional ventricular unipolar sensing signal. The outputs from the respective atrial and ventricular EGM amplifiers are algebraically multiplied, and the multiplied signal is applied to a threshold detector. Capture is verified when the multiplied signal experiences a positive voltage spike that exceeds a predetermined threshold in the threshold detector.
摘要:
The invention is directed to a programmer for communication with different medical devices that utilize different telemetry communication techniques. The programmer receives telemetry signals from a given medical device, and selects an appropriate communication mode, which can be pre-programmed into the programmer as one of a plurality of possible communication modes. The programmer can configure itself for communication with a given medical device based on the telemetry signal it receives. Specifically the programmer is implemented as a software based, power efficient receiver/transmitter based upon an inexpensive, simple motor-controller DSP.
摘要:
Methods and apparatus for interrogation of implantable medical device (IMD) information, including programmed parameter values, operating modes and programmed changes thereof and data stored in the IMD, by emission of audible sounds by the IMD are disclosed. The IMD includes an audio transducer that emits audible sounds including voiced statements or musical tones stored in analog memory correlated to a programming or interrogation operating algorithm or to a warning trigger event. The audible sounds can comprise the sole uplink transmission or may augment the contemporaneous uplink RF transmission of stored data, and/or programmed operating modes and parameters and/or device operations and states in an interrogation or during programming. To conserve energy, the audible sounds accompanying interrogation and programming of the IMD are at a low volume that preferably cannot be heard without use of an external audio amplifier or stethoscope. Voiced statements warning of battery energy depletion or imminent delivery of a therapy are emitted at a higher volume that is sufficient to be heard by the patient, so that the patient can take appropriate action. The volume of audible sounds confirming programmed changes made by a patient using a limited function programmer or magnet is also increased so that the patient can hear them.
摘要:
A method and apparatus for interpreting and displaying the status and diagnostic data of, and/or programming an implantable medical device is disclosed. The apparatus includes a microprocessor with multiple executable programs; data entry means, such as a keyboard or light pen; a display means such as a screen display and/or a printer; and may include a receiver and transmitter means for remote programming and interrogation of the implantable medical device. The apparatus further includes a stored audio signal to represent the status and diagnostic values of the implantable medical device.
摘要:
A rate-responsive cardiac pacemaker comprising a minute ventilation circuit and an activity circuit. The minute ventilation circuit computes a first target pacing rate as a function of measurements of the patient's pleural blood impedance, and the activity circuit computes a second target pacing rate as a function of measured levels of patient activity. A rate control function establishes a rate-responsive pacing rate based on the first and second target pacing rates. The minute ventilation circuit delta-modulates an analog impedance waveform and maintains short-term and long-term weighted averages of delta-modulator output counts. Variations in the difference between the short-term and long-term weighted average values are determinative of the first target pacing rate. Variations in an activity sensor output signal are determinative of the second target pacing rate. Physician-programmable parameters for the pacemaker include selection of a rate-response setting, upper and lower pacing rate limits, and rate-smoothing attack and decay settings.
摘要:
An integrated activation system for an implantable medical device (IMD) sharing a power source, the activation system comprising a switching circuit having first and second inputs and having an output coupled to the acute use device, a gating element coupled to the first input and configured to gate power from the power source to the switching circuit, and a sensing element coupled to the second input of the switching circuit. The sensing element is configured to sense an activation condition, enable an operation interval of the switching circuit, and transmit a signal to the switching circuit during the activation condition. The switching circuit is configured to transmit power to the acute use device upon receipt of a pre-determined number of signals from the sensing element.
摘要:
An integrated activation system for an implantable medical device (IMD) sharing a power source, the activation system comprising a switching circuit having first and second inputs and having an output coupled to the acute use device, a gating element coupled to the first input and configured to gate power from the power source to the switching circuit, and a sensing element coupled to the second input of the switching circuit. The sensing element is configured to sense an activation condition, enable an operation interval of the switching circuit, and transmit a signal to the switching circuit during the activation condition. The switching circuit is configured to transmit power to the acute use device upon receipt of a pre-determined number of signals from the sensing element.
摘要:
An integrated activation system for an implantable medical device (IMD) sharing a power source, the activation system comprising a switching circuit having first and second inputs and having an output coupled to the acute use device, a gating element coupled to the first input and configured to gate power from the power source to the switching circuit, and a sensing element coupled to the second input of the switching circuit. The sensing element is configured to sense an activation condition, enable an operation interval of the switching circuit, and transmit a signal to the switching circuit during the activation condition. The switching circuit is configured to transmit power to the acute use device upon receipt of a pre-determined number of signals from the sensing element.
摘要:
The operational and functional aspects of one or more IMDs is controlled by physiological data acquired from an external device. Various externally deployed devices collect vital signals for transmission to the IMD. Upon receipt of the signals the IMD cooperatively modifies therapy and diagnostic procedures to be substantially compliant with the received signals. Further, the IMD may store some of the signals for future follow-up or patient data management as needed.
摘要:
A system for and method of providing power to an implanted medical device within a patient is disclosed. The system (250) includes a first (262) and a second heat conduit (264) positioned within the patient. A thermoelectric device (252) is connected to the first and second heat conduits for thermally converting the temperature difference between the conduits to a voltage. A DC-DC converter (254) is connected to the thermoelectric element and increases the voltage. A storage element (256) is connected to the DC-DC converter-for receiving the increased voltage. The storage element is also connected to the implanted medical device (258), thereby providing power to the implanted medical device.