Abstract: A method and device for delivering pre-excitation pacing to prevent or reduce cardiac remodeling following a myocardial infarction is described. The pre-excitation pacing is modulated in accordance with an assessment of cardiac function in order to balance the beneficial effects of stress reduction with hemodynamic compromise.

Abstract: This patent document discusses, among other things, systems, devices, and methods for predicting an occurrence of impending thoracic fluid accumulation and in one example, invoking a responsive therapy, such as to prevent or minimize the consequences of the impending thoracic fluid accumulation. One example of the present systems, devices, and methods senses or receives at least one parameter that is statistically associated with impending thoracic fluid accumulation from a subject. Using such parameter(s), a probability of impending thoracic fluid accumulation is estimated. A list of parameters determines which values are recurrently sensed or received at various desired time intervals. Another example of the present systems, devices, and methods weights the sensed or received parameter value(s) to compute the probability estimate of impending thoracic fluid accumulation.

Abstract: A system to monitor heart sounds, such as to detect a worsening condition of heart failure decompensation. The system comprises a medical device that includes an implantable multi-axis heart sound sensor, operable to produce, for each of at least two nonparallel axes, an electrical signal representative of at least one heart sound, the heart sound associated with mechanical activity of a patient's heart. The device further includes a controller circuit coupled to the heart sound sensor. The controller circuit measures components of the heart sound that respectively correspond to each of the axes.

Abstract: Various aspects of the present subject matter relate to an implantable device. Various device embodiments comprise at least one port to connect to at least one lead with at least electrode, stimulation circuitry connected to the at least one port and adapted to provide at least one neural stimulation therapy to at least one neural stimulation target using the at least one electrode, sensing circuitry connected to the at least one port and adapted to provide a sensed signal, and a controller connected to the stimulation circuitry to provide the at least one neural stimulation therapy and to the sensing circuitry to receive the sensed signal. In response to a triggering event, the controller is adapted to switch between at least two modes. Other aspects and embodiments are provided herein.

Abstract: This document discusses, among other things, systems, devices, and methods measure an impedance and, in response, adjust an atrioventricular (AV) delay or other cardiac resynchronization therapy (CRT) parameter that synchronizes left and right ventricular contractions. A first example uses parameterizes a first ventricular volume against a second ventricular volume during a cardiac cycle, using a loop area to create a synchronization fraction (SF). The CRT parameter is adjusted in closed-loop fashion to increase the SF. A second example measures a septal-freewall phase difference (PD), and adjusts a CRT parameter to decrease the PD. A third example measures a peak-to-peak volume or maximum rate of change in ventricular volume, and adjusts a CRT parameter to increase the peak-to-peak volume or maximum rate of change in the ventricular volume.

Abstract: This document discusses, among other things, systems, devices, and methods measure an impedance and, in response, adjust an atrioventricular (AV) delay or other cardiac resynchronization therapy (CRT) parameter that synchronizes left and right ventricular contractions. A first example uses parameterizes a first ventricular volume against a second ventricular volume during a cardiac cycle, using a loop area to create a synchronization fraction (SF). The CRT parameter is adjusted in closed-loop fashion to increase the SF. A second example measures a septal-freewall phase difference (PD), and adjusts a CRT parameter to decrease the PD. A third example measures a peak-to-peak volume or maximum rate of change in ventricular volume, and adjusts a CRT parameter to increase the peak-to-peak volume or maximum rate of change in the ventricular volume.

Abstract: A neural stimulation system includes a safety control system that prevents delivery of neural stimulation pulses from causing potentially harmful effects. The neural stimulation pulses are delivered to one or more nerves to control the physiological functions regulated by the one or more nerves. Examples of such harmful effects include unintended effects in physiological functions associated with autonomic neural stimulation and nerve injuries caused by excessive delivery of the neural stimulation pulses.

Abstract: This patent document discusses systems, devices, and methods for increasing a sensitivity or specificity of thoracic fluid detection in a subject and differentiating between pleural effusion and pulmonary edema. In one example, a thoracic impedance measurement circuit senses a thoracic impedance signal. In another example, a processor receives the thoracic impedance signal and determines whether such thoracic impedance signal is “significant.” A significant thoracic impedance signal indicates the presence of thoracic fluid and may be recognized by comparing the thoracic impedance signal (or variation thereof) to a thoracic impedance threshold. When a significant thoracic impedance signal is recognized, the processor is adapted to detect one or both of: a pleural effusion indication and a pulmonary edema indication using one or a combination of: physiologic information, patient symptom information, and posture information.

Abstract: Various aspects relate to a method. In various embodiments, a therapy of a first therapy type is delivered, and it is identified whether a therapy of a second therapy type is present to affect the therapy of the first therapy type. Delivery of the therapy is controlled based on the presence of the therapy of the second therapy type. Some embodiments deliver the therapy of the first type using one set of parameters in the presence of a therapy of a second type, and deliver the therapy of the first type using another set of parameters when the therapy of the second type is not present. In various embodiments, one of the therapy types includes a cardiac rhythm management therapy, and the other includes a neural stimulation therapy. Other aspects and embodiments are provided herein.

Abstract: Systems and methods to optimize atrioventricular delay during sensing or pacing of the atrium and for a plurality of sensed rates or pacing rates. In one example, a paced atrioventricular delay is calculated using a sensed atrioventricular interval and a paced atrioventricular interval. In another example, a plurality of paced atrioventricular delays for different pacing rates can be calculated. In another example embodiment, a plurality of sensed atrioventricular delays for different sensing rates can be calculated. Combinations of the various systems and methods are also possible.

Abstract: This patent document discusses, among other things, systems, devices, and methods for enhancing detection of pulmonary edema using, in addition to thoracic impedance, one or a combination of: physiologic information about a subject, at least one statistical parameter, a user-programmable detection level, at least one parameter associated with a previous pulmonary edema event, and patient symptom information about the subject. In one example, a (base) thoracic impedance threshold is modified to an adjusted thoracic impedance threshold. The adjusted thoracic impedance threshold provides an increased sensitivity of pulmonary edema detection as compared to the base thoracic impedance threshold. In another example, an alert is provided to a subject, a caregiver, or other user based on a pulmonary edema indication determined by the present systems, devices, and methods. In a further example, a therapy (provided to the subject) is adjusted or initiated in response to the pulmonary edema indication.

Abstract: Cardiac monitoring and/or stimulation methods and systems provide for monitoring, diagnosing, defibrillation and pacing therapies, or a combination of these capabilities, including cardiac systems incorporating or cooperating with neuro-stimulating devices, drug pumps, or other therapies. Embodiments of the present invention relate generally to implantable medical devices employing automated cardiac activation sequence monitoring and/or tracking for arrhythmia discrimination. Embodiments of the invention are directed to devices and methods involving sensing a plurality of composite cardiac signals using a plurality of implantable electrodes. A source separation is performed using the sensed plurality of composite cardiac signals and the separation produces one or more cardiac signal vectors associated with one or more cardiac activation sequences that is indicative of ischemia. A change of the one or more cardiac signal vectors is detected using the one or more cardiac signal vectors.

Abstract: Method and systems are directed to acquiring and organizing information associated with at least one syncope event. A syncope event may be a suspected syncope event, a verified syncope event or a syncope event that is suspected and verified. Automated processes are used to collect information associated with at least one syncope event and organize the information as a syncope log entry. At least one of acquiring the information and organizing the information is performed at least in part implantably.

Abstract: A method and apparatus for delivering therapy to treat ventricular tachyarrhythmias is described. In one embodiment, neural stimulation, anti-tachycardia pacing, and shock therapy are employed in a progressive sequence upon detection of a ventricular tachycardia.

Abstract: Cardiac monitoring and/or stimulation methods and systems that provide one or more of monitoring, diagnosing, defibrillation, and pacing. Cardiac signal separation is employed to detect, monitor, track and/or trend closed-loop cardiac resynchronization therapy using cardiac activation sequence information. Devices and methods involve sensing a plurality of composite cardiac signals using a plurality of electrodes, the electrodes configured for implantation in a patient. A source separation is performed using the sensed plurality of composite cardiac signals, producing one or more cardiac signal vectors associated with all or a portion of one or more cardiac activation sequences. A cardiac resynchronization therapy is adjusted using one or both of the one or more cardiac signal vectors and the signals associated with the one or more cardiac signal vectors.

Abstract: A presentation device such as a display screen or a printer provides for simultaneous presentation of temporally aligned cardiac and neural signals. At least one cardiac signal in the form of a cardiac signal trace or cardiac event markers and at least one neural signal in the form of a neural signal trace or neural event markers are simultaneously presented. The cardiac signal indicates sensed cardiac electrical activities and/or cardiac stimulation pulse deliveries. The neural signal indicates sensed neural electrical activities and/or neural stimulation pulse deliveries. In one embodiment, the presentation device is part of an external system communicating with an implantable system that senses cardiac and/or neural signals and delivers cardiac and/or neural stimulation pulses.

Abstract: Various aspects of the present subject matter relate to a method and a device. In various embodiments of the method, a neural activity signal is sensed, a feature from the sensed neural activity signal is extracted, and a neural marker for the extracted feature is created. The neural marker includes information regarding the extracted feature. In various embodiments, the device comprises a port to receive a neural activity signal, and a feature extractor adapted to receive and process the neural activity signal to produce a neural marker that includes information for the neural activity signal. In various embodiments, the device comprises a display, a memory adapted to store a neural marker associated with a sensed neural activity signal, and a controller adapted to communicate with the memory and the display to provide a representation of the neural marker on the display. Other aspects and embodiments are provided herein.

Abstract: This document discusses, among other things, a cardiac function management device or other implantable medical device that includes a test mode and a diagnostic mode. During a test mode, the device cycles through various electrode configurations for collecting thoracic impedance data. At least one figure of merit is calculated from the impedance data for each such electrode configuration. In one example, only non-arrhythmic beats are used for computing the figure of merit. A particular electrode configuration is automatically selected using the figure of merit. During a diagnostic mode, the device collects impedance data using the selected electrode configuration. In one example, the figure of merit includes a ratio of a cardiac stroke amplitude and a respiration amplitude. Other examples of the figure of merit are also described.

Abstract: Various aspects of the present subject matter relate to a system. Various embodiments of the system comprise at least one port to connect to at least one lead with at least one electrode, at least one stimulator circuit and at least one controller. The at least one stimulator circuit is connected to the at least one port and is adapted to deliver neural stimulation to a neural stimulation target using the at least one electrode. The at least one controller is adapted to determine when another energy discharge other than the neural stimulation to the neural stimulation target is occurring and to prevent delivery of the neural stimulation simultaneously with the other energy discharge. Other aspects and embodiments are provided herein.

Abstract: A system includes an implantable medical device that includes a trans-thoracic impedance measurement circuit providing a trans-thoracic impedance signal of a subject. A controller is coupled to the trans-thoracic impedance circuit. The controller extracts a respiration signal from the trans-thoracic impedance signal, measures a breathing volume of the subject using the amplitude of the respiration signal and a breathing volume calibration factor, computes an adjusted breathing volume calibration factor using a reference baseline value of the trans-thoracic impedance and a measured baseline value of the trans-thoracic impedance, and computes a calibrated breathing volume using the adjusted breathing volume calibration factor.