Methods, systems, computer-readable media, and apparatuses for obtaining at least one bodily function measurement are presented. A mobile device includes an outer body sized to be portable for user, a processor contained within the outer body, and a plurality of sensors physically coupled to the outer body. The sensors are configured to obtain a first measurement indicative of blood volume and a second measurement indicative of heart electrical activity in response to a user action. A blood pressure measurement is determined based on the first measurement and the second measurement. The sensors also include electrodes where a portion of a user's body positioned between the electrodes completes a circuit and a measurement to provide at least one measure of impedance associated with the user's body. A hydration level measurement is determined based on the measure of impedance.

A pacemaker system includes a drive-sense circuit (DSC) operably coupled to a pacemaker lead. The DSC generates a pace signal including electrical impulses based on a reference signal. The DSC provides the pace signal via the pacemaker lead to an electrically responsive portion of a cardiac conductive system of a subject to facilitate cardiac operation of a cardiovascular system of the subject. The DSC senses, via the pacemaker lead, cardiac electrical activity of the cardiovascular system of the subject that is generated in response to the pace signal and electrically coupled into the pacemaker lead and generates a digital signal that is representative of the cardiac electrical activity of the cardiovascular system of the subject that is sensed via the pacemaker lead. The DSC provides digital information to one or more processing modules that includes and/or is coupled to memory and that provide the reference signal to the DSC.

An electrical stimulation system includes a sheath that includes conductive points that are operative to facilitate electrical stimulation to a bodily portion of a user. Drive-sense circuits (DSCs) generate electrical stimulation signals based on reference signals and provide those electrical stimulation signals via electrodes to the conductive points of the sheath. The electrical stimulation signal is coupled into respective locations of the bodily portion of the user that are in proximity to or in contact with the conductive points of the sheath. In addition, the DSCs sense, via the conductive points of the sheath and via the electrodes, changes of the electrical stimulation signals based on coupling of them into the respective locations of the bodily portion of the user. The DSCs provide digital signals that are representative of the changes of the electrical stimulation signals to one or more processing modules that includes and/or is coupled to memory.

Described herein are methods, devices, and systems for identifying false R-R intervals, and false arrhythmia detections, resulting from R-wave undersensing or intermittent AV conduction block. Each of one or more of the R-R intervals is classified as being a false R-R interval in response to a duration the R-R interval being greater than a first specific threshold, and the duration the R-R interval being within a second specified threshold of being an integer multiple of at least X other R-R intervals for which information is obtained, wherein the integer multiple is at least 2, and wherein X is a specified integer that is 1 or greater. When performed for R-R intervals in a window leading up to a detection of a potential arrhythmic episode, results of the classifying can be used to determine whether the potential arrhythmic episode was a false positive detection.

Described herein are methods for use with an implantable system including at least an atrial leadless pacemaker (aLP). Also described herein are specific implementations of an aLP, as well as implantable systems including an aLP. In certain embodiments, the aLP senses a signal from which cardiac activity associated with a ventricular chamber can be detected by the aLP itself based on feature(s) of the sensed signal. The aLP monitors the sensed signal for an intrinsic or paced ventricular activation within a ventricular event monitor window. In response to the aLP detecting an intrinsic or paced ventricular activation itself from the sensed signal within the ventricular event monitor window, the aLP resets an atrial escape interval timer that is used by the aLP to time delivery of an atrial pacing pulse if an intrinsic atrial activation is not detected within an atrial escape interval.

Techniques that include applying machine learning models to episode data, including a cardiac electrogram, stored by a medical device are disclosed. In some examples, based on the application of one or more machine learning models to the episode data, processing circuitry derives, for each of a plurality of arrhythmia type classifications, class activation data indicating varying likelihoods of the classification over a period of time associated with the episode. The processing circuitry may display a graph of the varying likelihoods of the arrhythmia type classifications over the period of time. In some examples, processing circuitry may use arrhythmia type likelihoods and depolarization likelihoods to identify depolarizations, e.g., QRS complexes, during the episode.

An intracardiac ventricular pacemaker is configured to operate in in a selected one of an atrial-tracking ventricular pacing mode and a non-atrial tracking ventricular pacing mode. A control circuit of the pacemaker determines at least one motion signal metric from the motion signal, compares the at least one motion signal metric to pacing mode switching criteria, and, responsive to the pacing mode switching criteria being satisfied, switches from the selected one of the non-atrial tracking pacing mode and the atrial tracking pacing mode to the other one of the non-atrial tracking pacing mode and the atrial tracking pacing mode for controlling ventricular pacing pulses delivered by the pacemaker.

An example medical device system includes therapy delivery circuitry configured to deliver anti-tachycardia pacing (ATP) therapy to a heart of a patient via electrodes communicatively coupled to the therapy delivery circuitry. The ATP therapy includes one or more ATP trains. The medical device system also includes processing circuitry configured determine a first propagation time based on a comparison of features in a local electrogram and a far-field electrogram, such as the time from a fiducial point in the local electrogram and QRS onset in the far-field electrogram. The processing circuitry is also configured to determine, based on the first propagation time, a number of pulses to achieve a second propagation time and control the therapy delivery circuitry to deliver the ATP train of at least the number of pulses.

An example device for detecting one or more parameters of a cardiac signal is disclosed herein. The device includes one or more electrodes and sensing circuitry configured to sense a cardiac signal via the one or more electrodes. The device further includes processing circuitry configured to determine a representative signal based on the cardiac signal, the representative signal having a single polarity, and determine an end of a T-wave of the cardiac signal based on an area under the representative signal.

A system and method are provided. The system includes a HIS electrode configured to be located proximate to a HIS bundle. A pulse generator is coupled to the HIS electrode and is configured to deliver HIS bundle pacing (HBP), a right atrial (RA) electrode is located in a right atrium, a sensing circuitry coupled to the RA electrode and defines an RA sensing channel that does not utilize the HIS electrode. The system includes a memory including program instructions. The system includes a processor is configured to collect cardiac activity (CA) signals over the RA sensing channel utilizing the RA electrode. The CA signals include a far field (FF) component associated with a ventricular event (VE). The processor analyzes the FF component to identify first and second FF component (FFC) characteristics of interest (COI) of the ventricular event and utilizes the first FFC COI to apply a first capture class (CC) discriminator to distinguish between first and second capture classes. The first capture class includes first and second capture types. The processor utilizes the second FFC COI to apply a second CC discriminator to distinguish between at least one of i) the first and second capture types within the first capture class, or ii) third and fourth capture classes and manages HIS bundle pacing based on distinctions by the first and second CC discriminators.