An implantable medical device includes a plurality of electrodes to detect electrical activity, a motion detector to detect mechanical activity, and a controller to determine at least one electromechanical interval based on at least one of electrical activity and mechanical activity. The activity detected may be in response to delivering a pacing pulse according to an atrioventricular (AV) pacing interval using the second electrode. The electromechanical interval may be used to adjust the AV pacing interval. The electromechanical interval may be used to determine whether cardiac therapy is acceptable or whether atrial or ventricular remodeling is successful.

A pacemaker having a motion sensor delivers atrial-synchronized ventricular pacing by detecting events from a signal produced by the motion sensor and delivering ventricular pacing pulses at a rate that tracks the rate of the detected events. The pacemaker is configured to confirm atrial tracking of the ventricular pacing pulses by determining if detected events from the motion sensor signal are atrial events. The pacemaker is configured to adjust a control parameter used for detecting events from the motion sensor signal if atrial tracking is not confirmed.

A method and device for dynamic device based AV delay adjustment is provided. The method comprises electrodes that are configured to be located proximate to an atrial (A) site and a right ventricular (RV) site. The method utilizes one or more processors for detecting an atrial paced (Ap) event or atrial sensed (As) event, and measures an AV interval corresponding to an interval between the Ap event or the As event and a sensed ventricular (Vs) event. The AV interval is associated with a current heart rate (HR). The method automatically dynamically adjusts a first AV delay based directly on the measured AV interval, identifies a scale factor associated with the current HR, calculates a second AV delay by scaling the first AV delay based on the scale factor and manages a pacing therapy, utilized by the IMD, based on the first and second AV delays.

The present disclosure relates generally to pacing of the cardiac conduction system of a patient, and more particularly, to providing adaptive cardiac conducting system pacing therapy and to determining selective or non-selective capture of the cardiac conduction system by cardiac conduction system pacing therapy. The adaptive cardiac conduction system pacing therapy may adjust AV delay and VV delay based on various signals and metrics and may switch between cardiac conduction system pacing therapy exclusively and cardiac conduction system pacing therapy in combination with traditional left ventricular pacing therapy.

An implantable device for stimulating a heart to lower blood pressure, comprising: a stimulation unit configured to stimulate a ventricle, and a sensing unit for detecting atrial activity of the heart, wherein the stimulation unit is configured to stimulate the ventricle for at least one cardiac cycle with a predefined delay after detection of an atrial activity or to not stimulate the ventricle for at least one cardiac cycle.

A system and method are provided for managing atrial-ventricular (AV) delay adjustments. An AV interval is measured that corresponds to an interval between an atrial paced (Ap) event or an atrial sensed (As) event and a sensed ventricular (Vs) event. A candidate AV delay is set based on the AV interval and a bundle branch adjustment (BBA) value. A QRS characteristic of interest (COI) is measured while utilizing the candidate AV delay in connection with delivering a pacing therapy. The BBA value is adjusted and the candidate AV delay is reset based on the BBA value as adjusted. A collection of QRS COIs and corresponding candidate AV delays are obtained and one of the candidate AV delays is selected as a BBA AV delay. The pacing therapy is managed, based on the BBA AV delay.

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.

Systems and methods for monitoring and treating patients with heart failure are discussed. The system may receive patient atrioventricular (AV) conduction characteristic under different heart rates or patient conditions. Stimulation parameters including stimulation timing parameters may be stored in a memory. The system may include a stimulation control circuit configured to determine a parameter update schedule indicating a timing at which to update stimulation parameter using patient AV conduction characteristic, and dynamically update at least a portion of the stored set of stimulation parameters at the determined parameter update schedule. For a specified heart rate or heart rate range, a stimulation parameter may be selected from the set of the stimulation parameters for use during cardiac stimulation.

An implantable system includes a first leadless pacemaker (LP1) implanted in or on a first chamber of a heart and a second leadless pacemaker (LP2) implanted in or on a second chamber of the heart. The LP1 is configured to time delivery of one or more pacing pulses delivered to the first chamber of the heart based on timing of cardiac activity associated with the second chamber of the heart detected by the LP1 itself. The LP1 is also configured to transmit implant-to-implant (i2i) messages to the LP2. The LP2 is configured to time delivery of one or more pacing pulses delivered to the second chamber of the heart based on timing of cardiac activity associated with the second chamber of the heart as determined based on one or more i2i messages received by the LP2 from the LP1.

A pacemaker having a motion sensor is configured to set atrial event sensing parameters used for sensing atrial systolic events from a motion signal produced by the motion sensor. The pacemaker sets at least one atrial event sensing parameter by identifying ventricular electrical events and setting a sensing window following each of the ventricular electrical events. The pacemaker may determine a feature of the motion signal produced by the motion sensor during each of the sensing windows and set the atrial event sensing parameter based on the determined features.