A biventricular (BiV) implantable cardiac stimulator contains a stimulation control unit, one or more stimulation units, an impedance measurement unit and an impedance evaluation unit. The stimulation control unit is operatively connected to one or more stimulation units to control delivery of stimulation pulses by the one or more stimulation units. The stimulation control unit is configured to assess ventricular contractility based on an impedance signal generated by the impedance evaluation unit and to switch between at least a univentricular left ventricular stimulation mode and a biventricular stimulation mode and to evaluate the ventricular contractility in relation to the respective ventricular stimulation mode.

A system embodiment comprises an implantable device including controller circuitry, memory, a transceiver, and a generator configured to generate electrical stimulation to modulate the neural activity. The controller circuitry and the transceiver configured to cooperate to receive, from another device, data corresponding to a user-programmable stimulation pattern and store the data in the memory. The user-programmable pattern includes a programmable pattern of bursts with multiple burst durations and multiple burst interval sequences, and the bursts include pulses with a user-programmable wave morphology. The controller circuitry is operably connected to the memory and the generator to use the data stored in the memory to control generation of the electrical stimulation to provide the user-programmable stimulation pattern that includes the pulses with the user-programmable wave morphology and that includes the multiple burst durations and the multiple burst interval sequences.

Systems and methods for reducing ventricle filling volume are disclosed. In some embodiments, a stimulation circuit may be used to stimulate a patient's heart to reduce ventricle filling volume or even blood pressure. When the heart is stimulated at a consistent rate to reduce blood pressure, the cardiovascular system may over time adapt to the stimulation and revert back to the higher blood pressure. In some embodiments, the stimulation pattern may be configured to be inconsistent such that the adaptation response of the heart is reduced or even prevented. In some embodiments, a stimulation circuit may be used to stimulate a patient's heart to cause at least a portion of an atrial contraction to occur while the atrioventricular valve is closed. Such an atrial contraction may deposit less blood into the corresponding ventricle than when the atrioventricular valve is opened throughout an atrial contraction.

An implantable medical device (IMD) is configured with a pressure sensor. The IMD includes a housing and a diaphragm that is exposed to the environment outside of the housing. The diaphragm is configured to transmit a pressure from the environment outside of the housing to a piezoelectric membrane. In response, the piezoelectric membrane generates a voltage and/or a current, which is representative of a pressure change applied to the housing diaphragm. In some cases, only changes in pressure over time are used, not absolute or gauge pressures.

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 controlling blood pressure by controlling atrial pressure and atrial stretch are disclosed. In some embodiments, a stimulation circuit may be configured to deliver a stimulation pulse to at least one cardiac chamber of a heart of a patient, and at least one controller may be configured to execute delivery of one or more stimulation patterns of stimulation pulses to the at least one cardiac chamber, wherein at least one of the stimulation pulses stimulates the heart such that an atrial pressure resulting from atrial contraction of an atrium overlaps in time a passive pressure build-up of the atrium, such that an atrial pressure of the atrium resulting from the stimulation is a combination of the atrial pressure resulting from atrial contraction and the passive pressure build-up and is higher than an atrial pressure of the atrium would be without the stimulation, and such that the blood pressure of the patient is reduced.

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 adjustable component designed to cause blood to flow in a direction opposite to the normal direction (regurgitation) within the patient's heart; and a controller configured for adjusting the function of the at least one adjustable component based at least in part on sensor data from the at least one sensor.

Systems and methods for controlling blood pressure by controlling atrial pressure and atrial stretch are disclosed. In some embodiments, a stimulation circuit may be configured to deliver a stimulation pulse to at least one cardiac chamber of a heart of a patient, and at least one controller may be configured to execute delivery of one or more stimulation patterns of stimulation pulses to the at least one cardiac chamber, wherein at least one of the stimulation pulses stimulates the heart such that an atrial pressure resulting from atrial contraction of an atrium overlaps in time a passive pressure build-up of the atrium, such that an atrial pressure of the atrium resulting from the stimulation is a combination of the atrial pressure resulting from atrial contraction and the passive pressure build-up and is higher than an atrial pressure of the atrium would be without the stimulation, and such that the blood pressure of the patient is reduced.

Methods and devices for reducing ventricle filling volume are disclosed. In some embodiments, an electrical stimulator may be used to stimulate a patient's heart to reduce ventricle filling volume or even blood pressure. When the heart is stimulated in a consistent way to reduce blood pressure, the cardiovascular system may over time adapt to the stimulation and revert back to the higher blood pressure. In some embodiments, the stimulation pattern may be configured to be inconsistent such that the adaptation response of the heart is reduced or even prevented. In some embodiments, an electrical stimulator may be used to stimulate a patient's heart to cause at least a portion of an atrial contraction to occur while the atrioventricular valve is closed. Such an atrial contraction may deposit less blood into the corresponding ventricle than when the atrioventricular valve is opened throughout an atrial contraction.

An implantable medical device (IMD) is configured with a pressure sensor. The IMD includes a housing and a diaphragm that is exposed to the environment outside of the housing. The diaphragm is configured to transmit a pressure from the environment outside of the housing to a piezoelectric membrane. In response, the piezoelectric membrane generates a voltage and/or a current, which is representative of a pressure change applied to the housing diaphragm. In some cases, only changes in pressure over time are used, not absolute or gauge pressures.