Abstract: An implantable medical device can include a hermetically-sealed implantable housing, an exposed first conductor located on or near the housing, and at least one insulated second conductor located near the exposed first conductor. In an example, the implantable medical device can include an isolation test circuit to provide a test stimulus to the exposed first conductor and configured to measure a portion of the test stimulus coupled to the second conductor.

Abstract: One aspect of this disclosure relates to a system for dynamic battery management in implantable medical devices. An embodiment of the system includes two or more devices for measuring battery capacity for an implantable medical device battery. The embodiment also includes a controller connected to the measuring devices. The controller is adapted to combine the measurements from the measuring devices using a weighted average to determine battery capacity consumed. According to various embodiments, at least one of the measuring devices includes a coulometer. At least one of the measuring devices includes a capacity-by-voltage device, according to an embodiment. The system further includes a display in communication with the controller in various embodiments. The display is adapted to provide a depiction of battery longevity in units of time remaining in the life of the implantable medical device battery, according to various embodiments. Other aspects and embodiments are provided herein.

Abstract: During auto-threshold, autocapture, or other evoked response sensing, post-pace artifact is reduced by using a smaller coupling capacitor value than what is used when not in such an evoked response sensing configuration. This can be accomplished by borrowing another capacitor for use as the coupling capacitor. The borrowed capacitor can be a backup pacing capacitor from the same or a different pacing channel. The borrowed capacitor can also be a coupling capacitor from a different pacing channel.

Abstract: Methods and systems involve adjusting an energy used for safety pacing based on the capture threshold. The safety pacing energy may be adjusted prior to a capture threshold test. During the capture threshold test, backup safety paces are delivered using the adjusted pacing energy. Following suspension of automatic capture verification, the device may enter a suspension mode. During the suspension mode, safety pacing pulses are delivered using a pacing energy adjusted based on capture threshold.

Abstract: An implantable or other ambulatory medical device can include a magnetic field detector, such as configured to detect an intense magnetic field. In an example, the ambulatory or implantable medical device can include an inductive switching supply, such as including one or more of a peak current comparator, or a zero current comparator. In an example, the ambulatory or implantable medical device can include a controller circuit, configured to control a switch, such as to controllably charge an inductor included in the inductive switching supply.

Abstract: Methods and systems involve adjusting an energy used for safety pacing based on the capture threshold. The safety pacing energy may be adjusted prior to a capture threshold test. During the capture threshold test, backup safety paces are delivered using the adjusted pacing energy. Following suspension of automatic capture verification, the device may enter a suspension mode. During the suspension mode, safety pacing pulses are delivered using a pacing energy adjusted based on capture threshold.

Abstract: One aspect of this disclosure relates to a system for dynamic battery management in implantable medical devices. An embodiment of the system includes two or more devices for measuring battery capacity for an implantable medical device battery. The embodiment also includes a controller connected to the measuring devices. The controller is adapted to combine the measurements from the measuring devices using a weighted average to determine battery capacity consumed. According to various embodiments, at least one of the measuring devices includes a coulometer. At least one of the measuring devices includes a capacity-by-voltage device, according to an embodiment. The system further includes a display in communication with the controller in various embodiments. The display is adapted to provide a depiction of battery longevity in units of time remaining in the life of the implantable medical device battery, according to various embodiments. Other aspects and embodiments are provided herein.

Abstract: One aspect of this disclosure relates to a system for dynamic battery management in implantable medical devices. An embodiment of the system includes two or more devices for measuring battery capacity for an implantable medical device battery. The embodiment also includes a controller connected to the measuring devices. The controller is adapted to combine the measurements from the measuring devices using a weighted average to determine battery capacity consumed. According to various embodiments, at least one of the measuring devices includes a coulometer. At least one of the measuring devices includes a capacity-by-voltage device, according to an embodiment. The system further includes a display in communication with the controller in various embodiments. The display is adapted to provide a depiction of battery longevity in units of time remaining in the life of the implantable medical device battery, according to various embodiments. Other aspects and embodiments are provided herein.

Abstract: An implantable medical device or some other ambulatory medical device, such as a pacer, defibrillator, or other cardiac rhythm management device can include an electrical energy delivery circuit, such as including an integrated circuit comprising a first electrostimulation output terminal, a can terminal, and a switch control output. The ambulatory or implantable device can include at least two switches in series, each including a respective substrate electrically separate from the integrated circuit, and from each other, the switches configured to controllably isolate a conductive housing of the implantable medical device from the can terminal of the integrated circuit, such as in response to the switch control output.

Abstract: An implantable or other ambulatory medical device can include a magnetic field detector, such as configured to detect an intense magnetic field. In an example, the ambulatory or implantable medical device can include an inductive switching supply, such as including one or more of a peak current comparator, or a zero current comparator. In an example, the ambulatory or implantable medical device can include a controller circuit, configured to control a switch, such as to controllably charge an inductor included in the inductive switching supply.

Abstract: An implantable medical device can include a hermetically-sealed implantable housing, an exposed first conductor located on or near the housing, and at least one insulated second conductor located near the exposed first conductor. In an example, the implantable medical device can include an isolation test circuit to provide a test stimulus to the exposed first conductor and configured to measure a portion of the test stimulus coupled to the second conductor.

Abstract: An ambulatory or implantable device, such as a pacer, defibrillator, or other cardiac rhythm management device, can tolerate magnetic resonance imaging (MRI) or other noise without turning on an integrated circuit diode by selectively providing a bias voltage that can overcome an expected induced voltage resulting from the MRI or other noise.

Abstract: An implantable device, such as a pacer, defibrillator, or other cardiac rhythm management device, can include one or more MRI Safe components. In an example, the implantable device includes a battery including a first electrode and a second electrode separate from the first electrode. The second electrode includes a first surface and a second surface. The second electrode includes a slot through the second electrode from the first surface toward the second surface. The slot extends from a perimeter of the second electrode to an interior of the second electrode. The slot is configured to at least partially segment a surface area of the second electrode to reduce a radial current loop size in the second electrode.

Abstract: Methods and systems involve adjusting an energy used for safety pacing based on the capture threshold. The safety pacing energy may be adjusted prior to a capture threshold test. During the capture threshold test, backup safety paces are delivered using the adjusted pacing energy. Following suspension of automatic capture verification, the device may enter a suspension mode. During the suspension mode, safety pacing pulses are delivered using a pacing energy adjusted based on capture threshold.

Abstract: Methods and systems involve adjusting an energy used for safety pacing based on the capture threshold. The safety pacing energy may be adjusted prior to a capture threshold test. During the capture threshold test, backup safety paces are delivered using the adjusted pacing energy. Following suspension of automatic capture verification, the device may enter a suspension mode. During the suspension mode, safety pacing pulses are delivered using a pacing energy adjusted based on capture threshold.

Abstract: A system is described. The system includes a lithium battery, a charge storage capacitor electrically connected to the lithium battery, a first device, and at least one second device. The first device is electrically connected to the lithium battery and is powered by the lithium battery. The at least one second device is attached to the charge storage capacitor and adapted to read a rate of charge storage in the charge storage capacitor or to calculate the rate of charge storage by measuring both a time of charging and a charge stored or added to the charge storage capacitor during the time of charging.

Abstract: An implantable medical device performs impedance measurement and demodulation, such as for obtaining lead impedance measurements, or thoracic impedance measurements, such as for extracting respiration, cardiac stroke, or fluid status information. A 4-point FIR filter demodulator can be used to demodulate a two-phase current excitation waveform. The demodulator can also be used to measure noise for triggering a noise response. Among other things, an increased excitation current level can be used when noise is deemed to be present.

Abstract: During auto-threshold, autocapture, or other evoked response sensing, post-pace artifact is reduced by using a smaller coupling capacitor value than what is used when not in such an evoked response sensing configuration. This can be accomplished by borrowing another capacitor for use as the coupling capacitor. The borrowed capacitor can be a backup pacing capacitor from the same or a different pacing channel. The borrowed capacitor can also be a coupling capacitor from a different pacing channel.

Abstract: A system is described which has a battery, a device which is powered by the battery in an episodic manner, and a charge storage capacitor. The system has attached to the charge storage capacitor a device or devices capable of: reading the rate of charge storage; or measuring both time and charge stored or added to the charge storage capacitor so that a rate of charge storage may be calculated. The estimated replacement time for the battery, particularly for a lithium battery in a pacing device, is easily estimated. Also described herein is a process for estimating a level of energy depletion in the system.

Abstract: One aspect of this disclosure relates to a system for dynamic battery management in implantable medical devices. An embodiment of the system includes two or more devices for measuring battery capacity for an implantable medical device battery. The embodiment also includes a controller connected to the measuring devices. The controller is adapted to combine the measurements from the measuring devices using a weighted average to determine battery capacity consumed. According to various embodiments, at least one of the measuring devices includes a coulometer. At least one of the measuring devices includes a capacity-by-voltage device, according to an embodiment. The system further includes a display in communication with the controller in various embodiments. The display is adapted to provide a depiction of battery longevity in units of time remaining in the life of the implantable medical device battery, according to various embodiments. Other aspects and embodiments are provided herein.