Abstract: Systems and methods for pacing cardiac conductive tissue are described. An embodiment of a medical system includes an electrostimulation circuit to generate His-bundle pacing (HBP) pulses to stimulate a His bundle, and a cardiac event detector to detect a His-bundle activity within a time window following an atrial activity. The cardiac event detector may use a cross-chamber blanking, or an adjustable His-bundle sensing threshold, to avoid or reduce over-sensing of far-field atrial activity and inappropriate inhibition of HBP therapy. The electrostimulation circuit may deliver HBP in the presence of the His-bundle activity. The system may further recognize the detected His-bundle activity as either a FFPW or a valid inhibitory event, and deliver or withhold HBP therapy based on the recognition of the His-bundle activity.

Abstract: Systems and methods for detecting cardiac events in a patient are described herein. An embodiment of a medical system includes a detection circuit configured to detect cardiac events of the patient at different detection settings using physiologic information of the patient and a control circuit to determine a priority for each detected cardiac event based on the detection setting used to detect the respective cardiac event and to prioritize system resources for the detected cardiac event according to the determined priorities, wherein to prioritize system resources comprises to allocate memory space for the detected cardiac events or to prioritize data transmission of the detected cardiac events to an external system based on the determined priority for each respective cardiac event.

Abstract: Systems and methods for managing physiological events generated by a medical device in a patient are discussed. An exemplary system includes a controller circuit to receive information about a plurality of physiological events detected by a medical device in a patient, generate for each of the physiological events a respective feature set using the received information, and cluster the physiological events into different event groups using values of temporal or morphological features of the generated feature sets. The event groups each include a respective set of physiological events. The controller circuit can identify from at least one event group a representative event representing the physiological events of that event group, and output to a user or a process the representative event and an indication that the representative event has been determined and represents the set of physiological events in the even group.

Abstract: A system and method for extracting a cardiac signal from a spinal signal include measuring a spinal signal at one or more electrodes that are connected to a neurostimulator and implanted within a patient's spinal canal and processing the spinal signal to extract the cardiac signal, which includes features that are representative of the patient's cardiac activity. Processing the spinal signal to extract the cardiac signal can include filtering the spinal signal, or use of model reduction schemes such as independent component analysis. The extracted cardiac signal can include a number of features that correspond to an electrocardiogram and can be used to determine the patient's heart rate and/or to detect a cardiac anomaly. Cardiac features that are determined from the cardiac signal can additionally be used to adjust parameters of the stimulation that is provided by the neurostimulator.

Abstract: Systems and methods for detecting an arrhythmic event and storing physiological information associated with the detected arrhythmic event are described. A system may include a first detector to detect an arrhythmic event from a physiological signal sensed from a subject, and generate a confidence indicator indicating a confidence level of the detection of the arrhythmic event. If the confidence indicator indicates a relatively high confidence of arrhythmia detection, the system may provide the detected arrhythmic event to a first process for storing the detected arrhythmic event or generating an alert. If the confidence indicator indicates a relatively low confidence of arrhythmia detection, the system may provide the detected arrhythmic event to at least a second process including confirming or rejecting the detected arrhythmic event.

Abstract: Systems and methods for classifying a cardiac arrhythmia are discussed. An exemplary system includes a correlator circuit to generate autocorrelation sequences using information of cardiac activity of a subject, including signal segments taken from a cardiac signal at respective elapsed time with respect to reference time. The correlator circuit can generate a correlation image using the autocorrelation sequences. The correlation image may be constructed by stacking the autocorrelation sequences according to the elapsed time of signal segments. An arrhythmia classifier circuit can classify the cardiac activity of the subject as one of arrhythmia types using the correlation image.

Abstract: Systems and methods for detecting physiologic events in a patient are described herein. An embodiment of a medical system includes a memory circuit to store physiologic event episodes detected and recorded by a medical device. The system includes a control circuit to analyze the stored physiologic event episodes, and determine a presence of a target cardiac event under a plurality of detection settings. Using the determined presence of the target cardiac event from the stored physiologic event episodes, and user adjudication of the stored event episodes, the control circuit may select, from the plurality of detection settings, a detection setting to detect a subsequent target cardiac event. The control circuit may also prioritize the physiologic event episodes for storage in the memory circuit.

Abstract: Systems and methods for detecting a physiological event or estimating a physiological parameter using ambulatory electrograms of a subject are discussed. An exemplary system includes a computing device that can receive ambulatory electrograms collected by an ambulatory medical device (AMD) associated with a subject, and apply the ambulatory electrograms to a trained machine learning model to estimate a physiological parameter or to detect a physiological event in the subject. The same or a different machine learning model can be trained to detect an operating status of the AMD using the ambulatory electrograms. The system comprises an output device to output the estimated physiological parameter, the detected physiological event, or the detected device operating status a user or a process such as to initiate or titrate a therapy.

Abstract: Systems and methods for pacing cardiac conductive tissue are described. In an embodiment, a medical system includes an electrostimulation circuit to generate pacing pulses to stimulate a His bundle or a bunch branch. A sensing circuit senses a far-field ventricular activation, determines a cardiac synchrony indicator using the far-field ventricular activation in response to His bundle or bundle branch pacing, and verifies His-bundle capture status using the determined cardiac synchrony indicator. The system can determine a pacing threshold using the capture status under different stimulation strength values. The electrostimulation circuit can deliver stimulation pulses in accordance with the determined pacing threshold.

Abstract: This document discusses, among other things, systems and methods to detect an initial arrhythmia event indication and, after a threshold amount of detection window intervals detecting the initial arrhythmia event indication, adjust a set of arrhythmia parameters or at least one of a respective set of parameter thresholds to increase sensitivity of an extended arrhythmia event indication detection.

Abstract: Systems and methods to determine an indication of patient dehydration are disclosed, including receiving first and second physiologic information of a patient, the first physiologic information including heart sound information of the patient and the second physiologic information different than the first physiologic information, and determining the indication of patient dehydration using the received first and second physiologic information.

Abstract: Systems and methods for pacing cardiac conductive tissue are described. In an embodiment, a medical system includes an electrostimulation circuit to generate pacing pulses to stimulate a His bundle or a bunch branch. A sensing circuit senses a far-field ventricular activation, determines a cardiac synchrony indicator using the far-field ventricular activation in response to His bundle or bundle branch pacing, and verifies His-bundle capture status using the determined cardiac synchrony indicator. The system can determine a pacing threshold using the capture status under different stimulation strength values. The electrostimulation circuit can deliver stimulation pulses in accordance with the determined pacing threshold.

Abstract: Systems and methods for detecting cardiac arrhythmias such as atrial tachyarrhythmia (AT) are discussed. An exemplary system includes an arrhythmia detector circuit that can receive physiologic information sensed from a patient over time, detect an arrhythmia onset when the physiologic information during a first time period satisfies an onset condition, and in response to the detected arrhythmia onset, detect an arrhythmia termination when the physiologic information during a second time period, subsequent to and longer than the first time period, satisfies an exit condition. An arrhythmia episode can be detected based on an arrhythmia duration between the detected onset and termination. The detected sustained arrhythmia episode can be provided to a user or a processor for further processing.

Abstract: A device for the active fixation of an implantable medical lead includes a housing, a tine assembly, an electrode, and a rotatable shaft. The housing includes a proximal end for connecting to the lead and a distal end opposite the proximal end. The housing defines a housing lumen extending between the proximal end and a recess adjacent to the distal end. The tine assembly is disposed within the housing lumen and includes at least one tine configured to self-bias from a linear configuration within the housing to a curved configuration outside of the housing. The electrode assembly is disposed at the distal end of the housing and includes a plurality of electrodes. The rotatable shaft extends through the housing lumen and is configured to engage the tine assembly such that rotation of the shaft transitions the at least one tine between the linear configuration and the curved configuration.

Abstract: This document discusses, among other things, systems and methods to receive cardiac electrical information of a subject, detect a premature ventricular contraction (PVC) event in a first detection window using the received cardiac electrical information, determine a count of detected PVC events in the first detection window, remove cardiac electrical information associated with the detected PVC event from the first detection window based on the determined count of detected PVC events, and detect an indication of atrial fibrillation of the subject for the first detection window using remaining cardiac electrical information in the first detection window.

Abstract: A system and method for extracting a cardiac signal from a spinal signal include measuring a spinal signal at one or more electrodes that are connected to a neurostimulator and implanted within a patient's spinal canal and processing the spinal signal to extract the cardiac signal, which includes features that are representative of the patient's cardiac activity. Processing the spinal signal to extract the cardiac signal can include filtering the spinal signal, or use of model reduction schemes such as independent component analysis. The extracted cardiac signal can include a number of features that correspond to an electrocardiogram and can be used to determine the patient's heart rate and/or to detect a cardiac anomaly. Cardiac features that are determined from the cardiac signal can additionally be used to adjust parameters of the stimulation that is provided by the neurostimulator.

Abstract: Systems and methods for managing medical information storage and transmission are discussed. A data management system may include a receiver circuit to receive information about a physiological event sensed from a patient, and an event prioritizer circuit to assign a priority to the received information. A control circuit may perform data reduction of the received information according to the assigned priority. Data reduction at a higher reduction rate is performed on the received information if a lower priority is assigned than if a higher priority is assigned. The system may include an output circuit to output the received information to a user or a process, or to transmit the received information to an external device, according to the assigned priority.

Abstract: Systems and methods for ambulatory detection of Q wave-to-T wave (QT) interval prolongation are discussed. A medical-device system comprises a controller circuit and a user interface device. The controller circuit includes a long QT syndrome (LQTS) detector that measures a QT interval from a subcutaneous cardiac signal sensed from a patient using implantable electrodes, and detects an indication of QT prolongation using the measured QT time interval and a programmable threshold received as a user input from the user interface. The control circuit can adjust device operation based on the detected indication of QT prolongation. An output unit can generate a programmable alert of the QT prolongation corresponding to the user input of the programmable threshold.

Abstract: Systems and methods for managing machine-generated alert notifications of medical events detected from one or more patients are described herein. An embodiment of a data management system may receive an adjudication of a medical event episode including an episode characterization. A storage unit stores an association between one or more episode characterizations and corresponding detection algorithms for detecting a medical event having respective episode characterizations. An episode management circuit may detect from a subsequent episode, using the stored association, a medical event having an episode characterization of at least one medical event episode presented for adjudication, and schedule presenting at least a portion of the subsequent episode based on the detection.

Abstract: A system and method for extracting a cardiac signal from a spinal signal include measuring a spinal signal at one or more electrodes that are connected to a neurostimulator and implanted within a patient's spinal canal and processing the spinal signal to extract the cardiac signal, which includes features that are representative of the patient's cardiac activity. Processing the spinal signal to extract the cardiac signal can include filtering the spinal signal, or use of model reduction schemes such as independent component analysis. The extracted cardiac signal can include a number of features that correspond to an electrocardiogram and can be used to determine the patient's heart rate and/or to detect a cardiac anomaly. Cardiac features that are determined from the cardiac signal can additionally be used to adjust parameters of the stimulation that is provided by the neurostimulator.