An implantable medical device for stimulating a human/animal heart having a stimulation unit which stimulates the His bundle and a detection unit which detects an electrical signal at the His bundle. The device performs: a) determining a first value of a parameter of a first measuring pulse measured between a first electrode pole and a housing; b) determining a second value of the same parameter of a second measuring pulse measured between the first electrode pole and a second electrode pole; c) comparing the first and second values; d) determining, based on the comparing step, whether the first or second measuring pulses enables a higher available level control range of the analog-to-digital converter; e) measuring an impedance in a unipolar manner between the first electrode pole and the housing or in a bipolar manner between the first electrode pole and the second electrode pole depending on the determining step.

Some aspects relate to systems, devices, and methods of delivering rate responsive pacing therapy. The method includes monitoring activity information related to an activity level of a patient and delivering rate responsive pacing (RRP) to the patient at a pacing rate corresponding to a RRP profile. The RRP profile may be used to generate the pacing rate based on the activity information and may be adjusted based on the monitored activity information.

An apparatus comprises a respiration sensing circuit configured for coupling electrically to a plurality of electrodes and for sensing a respiration signal representative of respiration of a subject; a signal processing circuit electrically coupled to the respiration sensing circuit and configured to extract a respiration parameter from a sensed respiration signal and determine a signal performance metric for the sensed respiration signal using the respiration parameter; and a control circuit. The control circuit is configured to: initiate sensing of a plurality of respiration signals using different electrode combinations of the plurality of electrodes and determining of the signal performance metric for the sensed respiration signals; and enable an electrode combination from the plurality of electrodes and for use in monitoring respiration of the subject according to the signal performance metric.

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.

Systems and methods are provided for optimizing hemodynamics within a patient's heart, e.g., to improve the patient's exercise capacity. In one embodiment, a system is configured to be implanted in a patient's body to monitor and/or treat the patient that includes at least one sensor configured to provide sensor data that corresponds to a blood pressure within or near the patient's heart; at least one component designed to cause dyssynchrony of the right ventricle, and a controller configured for adjusting the function of the at least one component based at least in part on sensor data from the at least one sensor.

Systems and methods include differential diagnosis for acute heart failure to provide treatment to a patient including determining whether the patient has cardiac volume overload, determining whether the patient has decreased abdominal venous system volume, and providing the appropriate treatment in response to the determinations. A multi-sensor system may be used to determine cardiac volume and abdominal venous system volume. Fluid redistribution treatment may be provided when cardiac volume overload is accompanied by a decrease in abdominal venous system volume. Fluid accumulation treatment may be provided when cardiac volume overload is not accompanied by a decrease in abdominal venous system volume.

An example method includes establishing a communications link between an electrophysiology (EP) monitoring system and an implantable medical device (IMD). IMD electrical data is received at the monitoring system via the communications link. The IMD electrical data may be synchronized with EP measurement data to provide synchronized electrical data based on timing of a synchronization signal sensed by an IMD electrode and/or EP electrodes. The method also includes computing reconstructed electrical signals for locations on a surface of interest within the patient's body based on the synchronized electrical data and geometry data. The geometry data represents locations of the EP electrodes, a location of the IMD electrode within the patient's body and the surface of interest.

The present invention relates to non-excitatory electrical heart failure therapy as a therapy for Heart failure with preserved ejection fraction.

Implantable devices and systems include one or more leads adapted to be emplaced in the internal thoracic vein (ITV) of a patient. The lead may include features to adapt the lead for such placement. An associated device for use with the lead may include operational circuitry adapted for use with a lead having an electrode for sensing and/or therapy purposes coupled thereto. Methods for implantation and use of such devices and systems are disclosed as well.

A system comprising a plurality of electrodes adapted to measure bio impedance measurements using electrical currents passing in a target thorax area of a target therebetween during a learning phase, at least one radiofrequency (RF) sensor adapted to measure RF interaction measurements of RF radiation interacting with the target thorax area during the learning phase, and at least one processor adapted to: calculate calibration function according to the bio impedance measurements and the RF interaction measurements, and determine a target thorax area value by adjusting subsequent bio impedance measurements using subsequent electrical currents passing in the target thorax area during an operational learning phase using the calibration function.