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.

Baseline BiV pacing is delivered and a corresponding baseline BiV efficacy score is determined. Intrinsic AV conduction is allowed and an intrinsic AV conduction interval is determined. BiV fusion pacing is delivered and a corresponding efficacy score is determined, for each of a plurality of different paced AV delays, each determined based on the intrinsic AV conduction interval and a different negative hysteresis delta. The baseline BiV pacing is selected for delivery during a period of time if the baseline BiV efficacy score is better than all of the efficacy scores. BiV fusion pacing is selected for delivery during the period of time, using one of the plurality of different paced AV delays for which a corresponding efficacy score was determined, if the efficacy score corresponding to at least one of the plurality of different paced AV delays is better than the baseline BiV efficacy score.

Systems and methods are provided for optimizing hemodynamics within a patient. Specifically, the system incorporates invasive sensor data (e.g., pressure measurements) combined with mechanisms to dynamically change the loading conditions of the heart and/or heart rate, in order to understand hemodynamic parameters. Computational analyses on dynamic sensor data are used to understand and guide heart rate, filling pressures, and/or volume resuscitation in critically ill patients. By pacing the heart or inducing tricuspid regurgitation, the system may cause dynamic changes in sensor data to understand optimal loading conditions and heart rates. While determining optimal hemodynamic parameters, the system may then automatically optimize the heart rate and/or filling pressures in critically ill patients.

A system for monitoring and evaluating the ventricular contractility of a heart muscle includes a device for electrically stimulating the heart muscle of a patient, and an extracorporeal blood pressure sensor. A record, responsive to stimulated ventricular contractions, is created by the pressure sensor. The response record is then evaluated to identify a pressure/time, rate-change in arterial pressure (dp/dt) that results within the time duration of a ventricular contraction in a cardiac cycle. In turn, dp/dt is evaluated as an indicator of ventricular contractility and the health of the patient's heart muscle.

A method for identifying reversible cardiac dyssynchrony (RCD) of a patient and treating the RCD measures an event relating to a rapid increase in the rate of pressure increase within the left ventricle. The method calculates a first time delay between the event and a first reference time. If the first time delay is longer than a set fraction of electrical activation of the heart, then the presence of cardiac dyssynchrony in the patient is identified. Pacing is applied to the heart, and a second time delay between the event following pacing and a second reference time following pacing is calculated. If the second time delay is shorter than the first time delay, the method identifies a shortening of a delay to onset of myocardial synergy, OoS, thereby identifying the presence of RCD in the patient. Treatment of the RCD is performed.

An implantable medical device, such as a sensor for monitoring a selected internally detectable physiological parameter of a patient, is attached to a fixation assembly that is deployable within the patient to position and orient the sensor to enable it to perform its function. The fixation assembly is formed having at least one flexible asymmetric connector where each fixation member includes a plurality of loops, wherein a first loop of the plurality of loops has a maximum pitch that is different from a maximum pitch of a second loop of the plurality of loops. The attachment of the housing and the fixation assembly includes providing a tubular member that is welded to the housing and crimped over a section of the fixation assembly.

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 leadless pacemaker device for providing an intra-cardiac pacing includes processing circuitry configured to generate ventricular pacing signals for stimulating ventricular activity at a ventricular pacing rate, a first sensor configuration receiving a first sense signal, and a second sensor configuration receiving a second sense signal. The processing circuitry derives, in a first sensing state, atrial events from the first sense signal for controlling the ventricular pacing rate based on the atrial events. The processing circuitry switches, based on at least one switching criterion, from the first sensing state to a second sensing state in which the processing circuitry derives atrial events from the second sense signal. The second sense signal is received by the second sensor configuration for detection of atrial events and the second sensor configuration is a motion sensor or a sound sensor. A method for operating the pacemaker device is also provided.

Systems and methods for pacing cardiac conductive tissue are described. A medical system includes an electrostimulation circuit to generate His-bundle pacing (HBP) pulses for delivery at or near a His bundle of the heart. A control circuit may time the delivery of the HBP pulses within a tissue refractory period subsequent to an intrinsic His-bundle activation of a first His-bundle portion. Based on an evoked His-bundle activation of a second His-bundle portion, the system may determine whether correction of intra-Hisian block has occurred. The system additionally includes a threshold test circuit to determine an individualized pacing threshold representing minimal energy to excite the His bundle and to correct the cardiac conduction abnormality.

Embodiments described herein generally relate to methods and systems for monitoring and responding to changes in a patient's physiologic status. A method includes sensing pulmonary arterial pressure (PAP) and thoracic impedance of a patient at rest. The method also includes detecting, based on the sensed PAP, whenever the patient's PAP at rest is outside an acceptable range of PAP measures for the patient at rest, and detecting, based on the sensed thoracic impedance, whenever the patient's respiration at rest is outside an acceptable range of respiration measures for the patient at rest. Various different actions are triggered depending upon whether the patient's PAP at rest is outside the acceptable range of PAP measures for the patient at rest, and whether the patient's respiration at rest is within the acceptable range of respiration measures for the patient at rest. Other embodiments relate to similar methods performed at other levels of exertion.