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.

Systems and methods for dynamically controlling His-bundle pacing (HBP) according to an indication of a rate-related or intermittent atrioventricular (AV) block in a subject are disclosed. An exemplary medical system includes an AV conduction monitor to detect an indication of either a presence or an absence of intermittent or rate-related AV conduction disturbance using physiologic information of the subject. In the event that an intermittent or rate-related AV conduction disturbance is present, a control circuit provides a control signal to an electrostimulation circuit to deliver HBP pulses. If there is no indication of intermittent or rate-related AV conduction disturbance, or a previously detected intermittent or rate-related AV conduction disturbance has been terminated, the control circuit withholds or discontinues delivery of the HBP pulses to promote intrinsic ventricular conduction and activation.

A ventricular pacemaker is configured to determine a ventricular rate interval by determining at least one ventricular event interval between two consecutive ventricular events and determine a rate smoothing ventricular pacing interval based on the ventricular rate interval. The pacemaker is further configured to detect an atrial event from a sensor signal and deliver a ventricular pacing pulse in response to detecting the atrial event from the sensor signal. The pacemaker may start the rate smoothing ventricular pacing interval to schedule a next pacing pulse to be delivered upon expiration of the rate smoothing ventricular pacing interval.

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.

Systems and methods for managing heart failure are described. The system receives physiological information including a first HS signal corresponding to paced ventricular contractions and a second HS signal corresponding to intrinsic ventricular contractions. The system detects worsening heart failure (WHF) using the received physiological information. A signal analyzer circuit can generate a paced HS metric from the first HS signal and a sensed HS metric from the second HS signal, and determine a concordance indicator between the paced and the sensed HS metrics. In response to the detected WHF, the system can use the concordance indicator to generate a therapy adjustment indicator for adjusting electrostimulation therapy, or a worsening cardiac contractility indicator indicating the detected WHF is attributed to degrading myocardial contractility.

A leadless pacemaker device configured to provide for an intra-cardiac pacing, including: processing circuitry configured to generate ventricular pacing signals for stimulating ventricular activity, and a reception device for receiving a sensing signal indicative of an atrial activity, wherein the processing circuitry is configured to detect an atrial event derived from said sensing signal, wherein the atrial event is a valid atrial sense event, where a series of atrial events lie within a range for a normal atrial rate, and/or when the atrial rate variability is within a certain range indicating a regular atrial rhythm, wherein in case a valid atrial sense event is detected, the processing circuitry is further configured to: determine ventricular pacing events according to atrial events, calculate ventricular-atrial time delays, determine a correction value based a measured time delay and the calculated time delay, and adjust the ventricular pacing timing based on the correction value.

A leadless pacemaker device configured to provide for an intra-cardiac pacing, including: processing circuitry configured to generate ventricular pacing signals for stimulating ventricular tissue, and a reception device for receiving a sensing signal indicative of an atrial activity, wherein the processing circuitry is configured to detect an atrial event derived from said sensing signal, wherein the atrial event is a valid atrial sense event, where a series of atrial events lie within a range for a normal atrial rate, and/or when the atrial rate variability is within a certain range indicating a regular atrial rhythm, wherein in case a valid atrial sense event is detected, the processing circuitry is further configured to: determine ventricular pacing events according to atrial events, calculate ventricular-atrial time delays, determine a correction value based a measured time delay and the calculated time delay, and adjust the ventricular pacing timing based on the correction value.

Systems and methods for monitoring and treating patients with heart failure (HF) are discussed. The system may sense cardiac signals, and receives information about patient physiological or functional conditions. A stimulation parameter table that includes recommended values of atrioventricular delay (AVD) or other timing parameters maybe created at a multitude of patient physiological or functional conditions. The system may periodically reassess patient physiological or functional conditions. A therapy programmer circuit may dynamically switch between left ventricular-only pacing and biventricular pacing, or switch between single site pacing and multisite pacing based on the patient condition. The therapy programmer circuit may adjust AVD and other timing parameters using the cardiac signal input and the stored stimulation parameter table. A HF therapy may be delivered according to the determined stimulation site, stimulation mode, and the stimulation timing.

Systems and methods for monitoring and treating patients with heart failure (HF) are discussed. The system may sense cardiac signals, and receives information about patient physiological or functional conditions. A stimulation parameter table that includes recommended values of atrioventricular delay (AVD) or other timing parameters may be created at a multitude of patient physiological or functional conditions. The system may periodically reassess patient physiological or functional conditions. A therapy programmer circuit may dynamically switch between left ventricular-only pacing and biventricular pacing, or switch between single site pacing and multisite pacing based on the patient condition. The therapy programmer circuit may adjust AVD and other timing parameters using the cardiac signal input and the stored stimulation parameter table. A HF therapy may be delivered according to the determined stimulation site, stimulation mode, and the stimulation timing.

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.