Abstract: An implantable medical device, such as a pacemaker or implantable cardioverter defibrillator (ICD), is configured to automatically detect ingestion of medications to verify that prescribed medications are taken in a timely manner and at the correct dosage. Briefly, individual pills are provided with miniature radio frequency identification (RFID) devices capable of transmitting RFID tag signals, which identify the medication contained within the pill and its dosage. The implanted device is equipped with an RFID transceiver for receiving tag signals from a pill as it is being ingested. The implanted system decodes the tag to identify the medication and its dosage, then accesses an onboard database to verify that the medication being ingested was in fact prescribed to the patient and to verify that the correct dosage was taken. Warning signals are generated if the wrong medication or the wrong dosage was taken. Therapy may also be automatically adjusted.

Abstract: An implantable medical device, such as a pacemaker or implantable cardioverter defibrillator (ICD), is configured to automatically detect ingestion of medications to verify that prescribed medications are taken in a timely manner and at the correct dosage. Briefly, individual pills are provided with miniature radio frequency identification (RFID) devices capable of transmitting RFID tag signals, which identify the medication contained within the pill and its dosage. The implanted device is equipped with an RFID transceiver for receiving tag signals from a pill as it is being ingested. The implanted system decodes the tag to identify the medication and its dosage, then accesses an onboard database to verify that the medication being ingested was in fact prescribed to the patient and to verify that the correct dosage was taken. Warning signals are generated if the wrong medication or the wrong dosage was taken. Therapy may also be automatically adjusted.

Abstract: An implantable medical device, such as a pacemaker or implantable cardioverter defibrillator (ICD), is configured to automatically detect ingestion of medications to verify that prescribed medications are taken in a timely manner and at the correct dosage. Briefly, individual pills are provided with miniature radio frequency identification (RFID) devices capable of transmitting RFID tag signals, which identify the medication contained within the pill and its dosage. The implanted device is equipped with an RFID transceiver for receiving tag signals from a pill as it is being ingested. The implanted system decodes the tag to identify the medication and its dosage, then accesses an onboard database to verify that the medication being ingested was in fact prescribed to the patient and to verify that the correct dosage was taken. Warning signals are generated if the wrong medication or the wrong dosage was taken. Therapy may also be automatically adjusted.

Abstract: An implantable cardiac stimulation device which determines stimulation based upon the patient's body position and activity level while eliminating special implantation or calibration procedures. To eliminate such special implantation and calibration procedures, the stimulation device correlates the patient's body position using a multi-axis DC accelerometer or other sensor during times of high activity and determines a patient's standing position value. During other times, the stimulation device compares the signals from the accelerometer to the standing position value to determine the patient's current body position. Based upon the current body position and the activity level, the stimulation device determines the necessary stimulation to deliver to the patient.

Abstract: A processor controlled implantable cardiac stimulation device may be placed into a shelf mode for extending the shelf life of the device. The device includes a real time clock circuit, a watch dog timer circuit having a duty cycle, a telemetry circuit capable of operation in either an active mode or a standby mode, and ancillary circuits that sense cardiac activity and provides stimulation pulses to a heart. The device includes a power source for providing power to all of the circuits of the device and a shelf mode circuit that places the device into the shelf mode. The shelf mode circuit disables power to the ancillary circuits, decreases the duty cycle of the watch dog timer, sets the processor into a static state, and sets the telemetry circuit to the standby mode. The shelf mode circuit places the device into the shelf mode in response to shelf mode commands received by the telemetry circuit to set the device from an active powered mode to the shelf mode.

Abstract: An implantable cardiac stimulation device which determines stimulation based upon the patient's body position and activity level while eliminating special implantation or calibration procedures. To eliminate such special implantation and calibration procedures, the stimulation device correlates the patient's body position using a multi-axis DC accelerometer or other sensor during times of high activity and determines a patient's standing position value. During other times, the stimulation device compares the signals from the accelerometer to the standing position value to determine the patient's current body position. Based upon the current body position and the activity level, the stimulation device determines the necessary stimulation to deliver to the patient.

Abstract: An implantable cardiac stimulation device including an activity/position sensor that incorporates a magnetoresistive sensor and a magnet that are positioned so as to move relative to each other in response to activity and the body position of the patient when the device is implanted in the body of the patient. In one embodiment, the sensor includes a magnetoresistive sensor that is made from giant magnetoresistive (GMR) materials. Preferably, a magnet is positioned on a flexible cantilevered beam so as to be positioned adjacent the magnetoresistive sensor. Movement of the patient results in relative movement of the magnet with respect to the magnetoresistive sensor and generates a signal having an AC component corresponding to a patient's activity and a DC component corresponding to the patient's body position.

Abstract: An implantable cardiac device including an activity sensor that incorporates a magnetoresistive sensor and a magnet that are positioned so as to move relative to each other in response to activity of the patient when the device is implanted in the body of the patient. In one embodiment, the sensor includes a magnetoresistive sensor that is made from giant magnetoresistive (GMR) materials. In another embodiment, a magnet is positioned on a flexible cantilevered beam so as to be positioned adjacent the magnetoresistive sensor. Movement of the patient results in relative movement of the magnet with respect to the magnetoresistive sensor. The signal can be used by the implantable cardiac device's processor for adjusting the delivery of therapeutic electrical stimulation such as by adjusting the pacing rate of pacing pulses being delivered to the patient's heart.

Abstract: Methods and apparatus are provided for classifying cardiac events with an implantable cardiac device. Cardiac signals are stored in a buffer. When a significant cardiac event is confirmed, a corresponding segment of the stored cardiac signals is processed to generate a set of feature values. The set of feature values is compared to various sets of reference values. Each set of reference values preferably corresponds to a separate type of cardiac event, so that the cardiac device may classify the significant cardiac event by matching its set of feature values to a set of reference values.

Abstract: A sensor that is implantable within the body of a patient that provides an indication of movement and orientation of the patient. The sensor is comprised of a cylindrical enclosure having a central electrode positioned within the cavity formed by the enclosure that is co-axial with the axis of the cylinder. One or more peripheral electrodes are positioned within the cavity and extend in a direction parallel to the central electrode. An electrolytic fluid is positioned in the enclosure so that movement of the sensor results in variations in the amount of electrolytic solution between the central electrode and the one or more peripheral electrodes. An alternating current signal is applied to the central electrode and the one or more peripheral electrodes and the resulting voltage signal is measured between the central electrode and the one or more peripheral electrodes.