Described herein are implantable medical systems, and methods for use therewith, that provide a temperature based rate response for a patient within which the implantable medical system is implanted. Such a method can include sensing a blood temperature signal indicative of a core body temperature of the patient, and producing a relative temperature signal based on the blood temperature signal. The method can further include producing a moving baseline temperature signal based on the relative temperature signal, producing a proportional response signal based on the relative temperature signal and the moving baseline temperature signal, and producing a sensor indicated rate response signal based on the proportional response signal and a base rate. The sensor indicated rate response signal can also be based on a dip response signal and/or a slope response signal. Additionally, a pacing rate is controlled based on the sensor indicated rate response signal.

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 intracardiac pacemaker system is configured to produce physiological atrial event signals by a sensing circuit of a ventricular intracardiac pacemaker and select a first atrial event input as the physiological atrial event signals. The ventricular intracardiac pacemaker detects atrial events from the selected first atrial event input, determines if input switching criteria are met, and switches from the first atrial event input to a second atrial event input in response to the input switching criteria being met. The second atrial event input includes broadcast atrial event signals produced by a second implantable medical device and received by the ventricular intracardiac pacemaker.

A method and device for detecting phrenic nerve stimulation (PNS) in, or using, a cardiac medical device. A test signal sensitive to contraction of a diaphragm of a patient may be sensed and signal artifacts of the test signal within each of a first window of the test signal prior to a predetermined cardiac signal and a second window of the test signal subsequent to the predetermined cardiac signal may be determined. The PNS beat criteria may be evaluated, for example, using the test signal, which may be a heart sounds signal.

Described herein are methods, devices, and systems that improve arrhythmia episode detection specificity, such as, but not limited to, atrial fibrillation (AF) episode detection specificity. Such a method can include obtaining an ordered list of R-R intervals within a window leading up to a detection of a potential arrhythmia episode, determining a measure of a dominant repeated R-R interval pattern within the window, and comparing the measure of the dominant repeated R-R interval pattern to a pattern threshold. If the measure of the dominant repeated R-R interval pattern is below the pattern threshold, that is indicative of a regularly irregular pattern being present, and there is a determination that the detection of the potential arrhythmia episode does not correspond to an actual arrhythmia episode. Such embodiments can beneficially be used to significantly reduce the number of false positive arrhythmia detections.

This disclosure is directed to techniques for identifying false detection of pause-triggered episode in cardiac ECG data. In some examples, a medical system is configured to receive a cardiac electrogram of a pause-triggered episode, the cardiac electrogram sensed by a medical device via a plurality of electrodes, determine whether one or more of false pause detection criteria are satisfied based on the cardiac electrogram, wherein the one or more of false pause detection criteria comprise: at least one criterion for relative flatness of amplitude values of the cardiac electrogram in a time interval between a last pre-pause beat and a pause detection time, classify the pause-triggered episode as one of a plurality of classifications based on the determination of whether the false pause detection criterion is satisfied, and output an indication of the classification of the pause-triggered episode to a user display.

A method for analyzing a condition of a heart, comprises receiving a plurality of electric signals, which are acquired by non-invasive measurement on the skin of a person or animal, each signal representing electrical activity in a respective region of the heart of the person or animal; calculating a derivative value of each signal at a plurality of time instances; selecting a plurality of the calculated derivative values of a first signal and determining a first point in time of a first event based on the selected derivative values; selecting a plurality of the calculated derivative values of a second signal and determining a second point in time of a second event, corresponding to the first event, based on the selected derivative values of the second signal, and calculating at least one measure based on a difference of the first point in time and the second point in time.

A cardiac conduction simulation system for pacemakers includes a memory configured to store one or more inputs from one or more users. The one or more inputs include a selection of an arrhythmia scenario for a pacemaker. The system also includes a processor operatively coupled to the memory and configured to generate an electrogram signal for the pacemaker based at least in part on the selected scenario. The processor is also configured to process one or more output pacing signals received from the pacemaker. The processor is further configured to generate an electrocardiogram (ECG) signal in accordance with the processed one or more output pacing signals from the pacemaker.

Described herein are methods, devices, and systems that improve arrhythmia episode detection specificity, such as, but not limited to, atrial fibrillation (AF) episode detection specificity. Such a method can include obtaining an ordered list of R-R intervals within a window leading up to a detection of a potential arrhythmia episode, determining a measure of a dominant repeated R-R interval pattern within the window, and comparing the measure of the dominant repeated R-R interval pattern to a pattern threshold. If the measure of the dominant repeated R-R interval pattern is below the pattern threshold, that is indicative of a regularly irregular pattern being present, and there is a determination that the detection of the potential arrhythmia episode does not correspond to an actual arrhythmia episode. Such embodiments can beneficially be used to significantly reduce the number of false positive arrhythmia detections.

A system and method for measuring and monitoring charge states of one or more electrodes of an implanted stimulation lead system associated with an IPG. A Kelvin connection scheme operative with a switching circuit is provided for coupling select electrode terminals disposed in a Kelvin connection measurement loop in a switchable manner to sense and reference inputs of an analog-to-digital converter (ADC) configured as at least part of diagnostic circuitry for the IPG.