Abstract: In some examples, the disclosure describes an implantable medical device comprising a plurality of electrodes, sensing circuitry configured to sense a physiological electrical signal via the plurality of electrodes, and communication circuitry configured to transmit and/or receive a transconductance communication signal via the plurality of electrodes, wherein at least one electrode of the plurality of electrodes comprises a lower-capacitance portion and a higher-capacitance portion.

Abstract: A relatively compact implantable medical device includes a fixation member formed by a plurality of fingers mounted around a perimeter of a distal end of a housing of the device; each finger is elastically deformable from a relaxed condition to an extended condition, to accommodate delivery of the device to a target implant site, and from the relaxed condition to a compressed condition, to accommodate wedging of the fingers between opposing tissue surfaces at the target implant site, wherein the compressed fingers hold a cardiac pacing electrode of the device in intimate tissue contact for the delivery of pacing stimulation to the site. Each fixation finger is preferably configured to prevent penetration thereof within the tissue when the fingers are compressed and wedged between the opposing tissue surfaces. The pacing electrode may be mounted on a pacing extension, which extends distally from the distal end of the device housing.

Abstract: A biocompatible medical device may include an electrochemical sensor including a common reference electrode; at least one counter electrode; and a work electrode platform comprising a plurality of respective work electrodes, each respective work electrode electrically coupled to the common reference electrode and comprising a respective reagent substrate configured to react with a respective analyte to produce a respective signal indicative of a concentration of the respective analyte; and processing circuitry operatively coupled to the electrochemical sensor, and configured to receive from the electrochemical sensor a plurality of signals from the plurality of respective work electrodes; identify the respective signal corresponding to a respective selected work electrode; and process the identified signal to determine the concentration of the respective analyte associated with the respective selected work electrode.

Abstract: An electrochemical sensor may include a common reference electrode, at least one counter electrode, and a work electrode platform including a plurality of respective work electrodes. Each respective work electrode of the plurality of respective work electrodes may be electrically coupled to the common reference electrode and include a respective reagent substrate configured to react with a respective analyte to produce a signal indicative of a concentration of the respective analyte.

Abstract: An implantable medical device comprises a communication module that comprises at least one of a receiver module and a transmitter module. The receiver module is configured to both receive from an antenna and demodulate an RF telemetry signal, and receive from a plurality of electrodes and demodulate a tissue conduction communication (TCC) signal. The transmitter module is configured to modulate and transmit both an RF telemetry signal via the antenna and a TCC signal via the plurality of electrodes. The RF telemetry signal and the TCC signal are both within a predetermined band for RF telemetry communication. In some examples, the IMD comprises a switching module configured to selectively couple one of the plurality of electrodes and the antenna to the receiver module or transmitter module.

Abstract: A relatively compact implantable medical device includes a fixation member formed by a plurality of fingers mounted around a perimeter of a distal end of a housing of the device; each finger is elastically deformable from a relaxed condition to an extended condition, to accommodate delivery of the device to a target implant site, and from the relaxed condition to a compressed condition, to accommodate wedging of the fingers between opposing tissue surfaces at the target implant site, wherein the compressed fingers hold a cardiac pacing electrode of the device in intimate tissue contact for the delivery of pacing stimulation to the site. Each fixation finger is preferably configured to prevent penetration thereof within the tissue when the fingers are compressed and wedged between the opposing tissue surfaces. The pacing electrode may be mounted on a pacing extension, which extends distally from the distal end of the device housing.

Abstract: In some examples, determining a heart failure status includes using an implantable medical device configured for subcutaneous implantation and comprising a plurality of electrodes and an optical sensor. Processing circuitry of a system comprising the device may determine, for a patient, a current tissue oxygen saturation value based on a signal received from the at least one optical sensor, a current tissue impedance value based on a subcutaneous tissue impedance signal received from the electrodes, and a current pulse transit time value based on a cardiac electrogram signal received from the electrodes and at least one of the signal received from the optical sensor and the subcutaneous tissue impedance signal. The processing circuitry may further compare the current tissue oxygen saturation value, current tissue impedance value, and current pulse transit time value to corresponding baseline values, and determine the heart failure status of the patient based on the comparison.

Abstract: In some examples, determining a health status includes using an implantable medical device configured for subcutaneous implantation and comprising at least one optical sensor. Processing circuitry of a system comprising the device may determine, for a patient, a current tissue oxygen saturation value based on a first signal received from the at least one optical sensor and a current pulsatile oxygen saturation value based on a second signal received from the at least one optical sensor. The processing circuitry may further compare the current tissue oxygen saturation and current pulsatile oxygen saturation values to corresponding baseline values, determine corresponding heart failure and pulmonary statuses of the patient based on the comparisons, and determine the health status of the patient based on the statuses.

Abstract: The disclosure describes systems and techniques for detection of pump thrombosis in mechanical circulatory support (MCS) devices. An example pump thrombosis detection system includes a transducer and processing circuitry. The transducer may be configured to generate a signal representative of a mechanical wave from a mechanical circulatory support device. The processing circuitry is communicatively coupled to the transducer. The processing circuitry may be configured to determine an indication of pump thrombosis based on the signal and, based on the indication of pump thrombosis, control the pump thrombosis detection system to at least one of generate an alert or initiate an intervention.

Abstract: A method and device for implanting a medical lead. The device includes an elongate shaft defining a major longitudinal axis and including a proximal end and a distal end. A necked portion coupled to and extending from the distal end is included, the necked portion defines a first thickness and a substantially planar surface, the necked portion being at least resiliently movable in a direction normal to the major longitudinal axis. A tip disposed at the distal end of the necked portion is included, the tip defining a second thickness greater than the first thickness.

Abstract: In some examples, a medical system includes a medical device. The medical device may include a housing configured to be implanted in a target site of a patient, a light emitter configured to emit a signal configured to cause a fluorescent marker to emit a fluoresced signal into the target site, and a light detector that may be configured to detect the fluoresced signal. The medical system may include processing circuitry configured to determine a characteristic of the fluorescent marker based on the emitted signal and the fluoresced signal. The characteristic of the fluorescent marker may be indicative of a presence of a compound in the patient, and the processing circuitry may be configured to track the presence of the compound of the patient based on the characteristic of the fluorescent marker.

Abstract: The present disclosure provides an apparatus and method of detecting ischemia with a pressure sensor. The method can include obtaining a pressure signal and determining a pressure rate of change. The method can also include identifying at least one of impaired relaxation and impaired contractility in order to detect ischemia.

Abstract: The exemplary systems and methods may monitor one or more signals to be used to assess the hemodynamic status of a patient. The one or more signals may be used to calculate, or determine, a plurality of pulse transit times. The plurality of pulse transit times may be used to determine hemodynamic status values that may be indicative of a patient's aggregate hemodynamic status.

Abstract: A medical device for monitoring delivery of a therapy that includes a therapy delivery module to deliver a therapy, a controller to set a therapy delivery control parameter, an optical sensor to produce a signal corresponding to tissue light attenuation, and a processor configured to compute a tissue oxygenation measurement from the optical sensor signal, wherein the controller, the optical sensor, and the processor operate cooperatively to determine a setting of the therapy delivery control parameter corresponding to a maximum tissue oxygenation.

Abstract: Systems, devices, and techniques for establishing communication between two medical devices are described. In one example, an implantable medical device comprises communication circuitry, therapy delivery circuitry, and processing circuitry configured to initiate a communication window during which the implantable second medical device is capable of receiving the information related to a cardiac event detected by a first medical device, the communication window being one of a plurality of communication windows defined by a communication schedule that corresponds to a transmission schedule in which the first medical device is configured to transmit the information, control the communication circuitry to receive, from the first medical device, the information related to the cardiac event that is indicative of a timing of the cardiac event with respect to a timing of the communication window, schedule and control delivery of a therapy according to the information related to the cardiac event.

Abstract: In some examples, the disclosure describes an implantable medical device comprising a plurality of electrodes, sensing circuitry configured to sense a physiological electrical signal via the plurality of electrodes, and communication circuitry configured to transmit and/or receive a transconductance communication signal via the plurality of electrodes, wherein at least one electrode of the plurality of electrodes comprises a lower-capacitance portion and a higher-capacitance portion.

Abstract: A medical device system is configured to sense a physiological signal by a first device and generate a control signal by the first device in response to the physiological signal. An optical transducer is controlled by the first device to emit an optical trigger signal in response to the control signal. A second device receives the optical trigger signal and delivers an automatic therapy to a patient in response to detecting the optical trigger signal.

Abstract: An implantable medical device comprising a signal generator configured to generate and deliver anti-tachyarrhythmia pacing (ATP) to a heart of a patient and processing circuitry. The processing circuitry is configured to detect an enable event, responsive to detecting the enable event, enable the delivery of ATP by the signal generator, detect a disable event indicating that another implantable medical device cannot be relied upon to deliver an anti-tachyarrhythmia shock, and responsive to detecting the disable event, disable delivery of ATP.

Abstract: An implantable medical device comprises a communication module that comprises at least one of a receiver module and a transmitter module. The receiver module is configured to both receive from an antenna and demodulate an RF telemetry signal, and receive from a plurality of electrodes and demodulate a tissue conduction communication (TCC) signal. The transmitter module is configured to modulate and transmit both an RF telemetry signal via the antenna and a TCC signal via the plurality of electrodes. The RF telemetry signal and the TCC signal are both within a predetermined band for RF telemetry communication. In some examples, the IMD comprises a switching module configured to selectively couple one of the plurality of electrodes and the antenna to the receiver module or transmitter module.

Abstract: The exemplary systems and methods may monitor one or more signals to be used to assess the hemodynamic status of a patient. The one or more signals may be used to calculate, or determine, a plurality of pulse transit times. The plurality of pulse transit times may be used to determine hemodynamic status values that may be indicative of a patient's aggregate hemodynamic status.