According to various method embodiments, a person is indicated for a therapy to treat a cardiovascular disease, and the therapy is delivered to the person to treat the cardiovascular disease. Delivering the therapy includes delivering a vagal stimulation therapy (VST) to a vagus nerve of the person at a therapeutically-effective intensity for the cardiovascular disease that is below an upper boundary at which upper boundary the VST would lower an intrinsic heart rate during the VST.

The presence of a cardiac pulse in a patient is determined by evaluating fluctuations in an electrical signal that represents a measurement of the patient's transthoracic impedance. Impedance signal data obtained from the patient is analyzed for a feature indicative of the presence of a cardiac pulse. Whether a cardiac pulse is present in the patient is determined based on the feature in the impedance signal data. Electrocardiogram (ECG) data may also be obtained in time coordination with the impedance signal data. Various applications for the pulse detection of the invention include detection of PEA and prompting PEA-specific therapy, prompting defibrillation therapy and/or CPR, and prompting rescue breathing depending on detection of respiration.

A medical device for stimulating the heart using biventricular stimulation. The device includes a sensor for detecting an endocardial acceleration parameter and a processing circuit configured to receive the endocardial acceleration parameter. The device further includes stimulation electronics coupled to the processing circuit. The processing circuit is configured to use the EA parameter to evaluate the biventricular stimulation. The evaluation includes comparing the value of the EA parameter in biventricular mode to the value of the EA parameter in left only mode or right only mode, and using the comparison and an assessment of the variability of the EA parameter as a function of the AVD in the left or right mode to distinguish between cases comprising: (a) normal operation, (b) a loss of RV or LV capture, (c) possible anodal stimulation. The processing circuit is further configured to conduct at least one update to operational parameters of the device based on the determined case.

A method of operating a cardiac rhythm management (CRM) system includes sending a list of electrodes to an ambulatory medical device (AMD) of the CRM system from a programming device for the AMD, the list of electrodes including types of electrodes available to the AMD and position of the electrodes; sending a selection of one or more capture confirming criteria to confirm pacing capture to the AMD; performing, by the AMD, an automatic pacing threshold test for all potential pacing vectors that include the electrodes in the list of electrodes; collecting data for each pace of the pacing threshold test confirmed to capture according to the selected one or more capture confirming criteria; communicating the collected data to the programming device; and presenting the collected data as a trend relative to at least one selected capture confirming criterion and the pacing stimulation energy that resulted in capture.

Systems and methods for cardiac pacing are described in this document. A medical system includes an electrostimulation circuit to generate His-bundle pacing (HBP) pulses to capture a His bundle, and LV pacing (LVP) pulses to capture a left ventricle. A sensing circuit may sense a cardiac activity, such as an atrial or an LV cardiac electrical activity. The system includes a control circuit controlling the delivery of HBP and LVP pulses. The HBP and LVP may be delivered concurrently or sequentially. In an example, the LVP pulses may be delivered based on a His-bundle capture status in response to the HBP pulse. The system may adjust one or more His-bundle stimulation parameters based on the His-bundle capture status.

The disclosure relates to a device including a circuit for adjusting the energy of the stimulation pulses, independently controlling the pulse width and the voltage of each stimulation pulse. An iterative search algorithm for determining the optimum energy includes changing both the pulse width and voltage at each new pulse delivered, by setting a high energy value and a low energy value, and delivering a stimulation pulse with the low energy value. A capture test is then carried out. In the presence of a capture, a current iteration is complete and a new iteration is done with the current low energy as a new high energy value. In the absence of capture, the algorithm is terminated with selection of the last energy value that produced the capture as the value of optimum energy.

Systems and methods are provided for managing patient activated capture of transient data by an implantable medical device (IMD). The systems and methods collect transient data using the IMD. The collected transient data is stored in a temporary memory section of the IMD. The IMD receives a patient activated storage request including activation information related to a patient designated trigger point from an external device. The IMD transfers a segment of the transient data from the temporary memory section to a long-term memory, wherein the segment of transferred transient data is based on the trigger point. The activation information includes an elapsed time corresponding to a duration of time between entry of the trigger point and issuance of the patient activated storage request by an external activation device.

Systems and methods are provided for managing patient activated capture of transient data by an implantable medical device (IMD). The systems and methods collect transient data using the IMD. The collected transient data is stored in a temporary memory section of the IMD. The IMD receives a patient activated storage request including activation information related to a patient designated trigger point from an external device. The IMD transfers a segment of the transient data from the temporary memory section to a long-term memory, wherein the segment of transferred transient data is based on the trigger point. The activation information includes an elapsed time corresponding to a duration of time between entry of the trigger point and issuance of the patient activated storage request by an external activation device.

An extra-cardiovascular implantable cardioverter defibrillator (ICD) having a low voltage therapy module and a high voltage therapy module is configured to select, by a control module of the ICD, a pacing output configuration from at least a low-voltage pacing output configuration of the low voltage therapy module and a high-voltage pacing output configuration of the high voltage therapy module. The high voltage therapy module includes a high voltage capacitor having a first capacitance and the low voltage therapy module includes a plurality of low voltage capacitors each having up to a second capacitance that is less than the first capacitance. The ICD control module controls a respective one of the low voltage therapy module or the high voltage therapy module to deliver extra-cardiovascular pacing pulses in the selected pacing output configuration via extra-cardiovascular electrodes coupled to the ICD.

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.