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.

A pacemaker having a motion sensor is configured to select an atrial event sensing vector of a multi-axis motion sensor for sensing atrial systolic events from a motion signal produced by the motion sensor. In some examples, the pacemaker determines a maximum amplitude during a sensing window for each one of multiple vector signals produced by the multi-axis motion sensor. The pacemaker may select the atrial event sensing vector signal from among the vector signals based on the determined maximum amplitudes.

Systems and methods for dynamically controlling HBP delivery based on patient AV conduction status are disclosed. An exemplary medical system includes an electrostimulation circuit to generate HBP pulses to stimulate a His bundle or a bundle branch of the heart. An AV conduction monitor circuit continuously or periodically assesses AV conduction status, and detects an indication of presence or absence of AV conduction abnormality. If an AV conduction abnormality is indicated, a control circuit may control the electrostimulation circuit to deliver the HBP pulses. Ventricular backup pacing may be delivered if HBP fails to capture and elicit ventricular activation. When the AV conduction become normal, the control circuit may withhold HBP delivery and promote patient intrinsic ventricular activation.

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.

A method and system for delivering cardiac pacing therapy that includes sensing electrical activity of tissue of a patient from a plurality of external electrodes during delivery of a non-ambulatory pacing therapy from a pacing device and determining an optimal electromechanical (EM) response time from an optimal electrical activation determined from electrical heterogeneity information obtained during non-ambulatory pacing therapy. During delivery of subsequent ambulatory pacing, the pacing sensing an EM signal from an EM sensor of the pacing device, determines a current EM response time in response to the sensed EM signal, and adjusting a pacing parameter setting of the ambulatory pacing therapy in response to comparing the current EM response time to the optimal EM response time.

A medical device and medical device system for delivering left ventricular pacing that includes a subcutaneous sensing device having a subcutaneous electrode to sense a subcutaneous cardiac signal and an emitting device to emit a trigger signal in response to the sensed cardiac signal, an intracardiac therapy delivery device to deliver the left ventricular pacing in response to the emitted trigger signal, and a processor configured to determine whether the medical device system is in one of a VVD pacing mode and a VVI pacing mode, determine whether the delivered left ventricular pacing captures the left ventricle, determine whether to adjust a pacing parameter in response to the determination of whether the device system is in one of a VVD pacing mode and a VVI pacing mode and the determination of whether the delivered left ventricular pacing captures the left ventricle, and deliver the left ventricular pacing in response to determining whether to adjust the pacing parameter.

The invention provides methods related to improving heart function.

An intracardiac ventricular pacemaker is configured to detect a ventricular diastolic event from a motion signal received by a pacemaker control circuit from a motion sensor. The control circuit starts an atrial refractory period having an expiration time set based on a time of the detection of the ventricular diastolic event. The control circuit detects an atrial systolic event from the motion signal after expiration of the atrial refractory period and controls a pulse generator of the pacemaker to deliver a pacing pulse to a ventricle of a patient's heart at a first atrioventricular pacing time interval after the atrial systolic event detection.

Systems and methods for controlling blood pressure via electrical stimulation of the heart are disclosed. Embodiments may include at least two different stimulation patterns, each configured to reduce blood pressure to a different degree, and may alternate between stimulation patterns based on the need of a patient, for example, alternating between day and night or between periods of strenuous and light activity. Some embodiments may take advantage of a slow baroreflex response that occurs after treatment is stopped, suspending treatment for extended periods, and then resuming treatment before blood pressure levels reach pretreatment values. Embodiments may control blood pressure by controlling atrial pressure and atrial stretch.

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.