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.

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.

Implantable medical devices such as leadless cardiac pacemakers (LCP) may be configured to be delivered to a target location within the heart over a guide wire. In some cases, using a guide wire for delivery facilitates placement of devices in regions not otherwise easily reached. An LCP may include a housing and a wire lumen disposed relative to the housing. The wire lumen may be configured to allow the LCP to slide over a guide wire. In some cases, the guide wire may include a guide wire electrode that may be used to test potential implantation sites.

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.

Methods and devices are provided for, under control of one or more processors within an implantable medical device (IMD), delivering cardiac resynchronization therapy (CRT) at one or more pacing sites. The processors obtain cardiac signals, associated with a candidate beat, from multi-site left ventricular (MSLV) electrodes distributed along a left ventricle and analyze the cardiac signals to collect at least one of a MSLV conduction pattern or a MSLV morphology. The processors compare at least one of the MSLV conduction pattern or MSLV morphology to one or more associated templates. The processors then label the candidate beat as a pseudo-fusion beat based on the comparing and adjust the CRT based on the labeling.

An implantable device and associated method for delivering multi-site pacing therapy is disclosed. The device comprises a set of electrodes including a first ventricular electrode and a second ventricular electrode, spatially separated from one another and all coupled to an implantable pulse generator. The device comprises a processor configured for selecting a first cathode and a first anode from the set of electrodes to form a first pacing vector at a first pacing site along a heart chamber and selecting a second cathode and a second anode from the set of electrodes to form a second pacing vector at a second pacing site along the same heart chamber. The pulse generator is configured to deliver first pacing pulses to the first pacing vector and delivering second pacing pulses to the second pacing vector. The pulse generator generates a recharging current for recharging a first coupling capacitor over a first recharge time period in response to the first pacing pulses. The pulse generator for generating a recharging current for recharging a second coupling capacitor over a second recharge time period in response to the second pacing pulses. An order of recharging the first and second coupling capacitors is dependent upon one of ventricular pacing mode, left ventricle to right ventricle delay (V-V) pace delay, multiple point LV delay and latest delivered pacing pulses to one of the first and second pacing vectors.

Systems and methods involve an intrathoracic cardiac stimulation device operable to provide autonomous cardiac sensing and energy delivery. The cardiac stimulation device includes a housing configured for intrathoracic placement relative to a patient's heart. A fixation arrangement of the housing is configured to affix the housing at an implant location within cardiac tissue or cardiac vasculature. An electrode arrangement supported by the housing is configured to sense cardiac activity and deliver stimulation energy to the cardiac tissue or cardiac vasculature. Energy delivery circuitry in the housing is coupled to the electrode arrangement. Detection circuitry is provided in the housing and coupled to the electrode arrangement. Communications circuitry may optionally be supported by the housing. A controller in the housing coordinates delivery of energy to the cardiac tissue or cardiac vasculature in accordance with an energy delivery protocol appropriate for the implant location.

Methods and systems are provided for managing residual charge for multi-point pacing therapy. The method and system provide an electrode configuration that includes an atrial (A) electrode, a right ventricular (RV) electrode and multiple left ventricular (LV) electrodes. The method and system deliver pacing pulses for an MPP therapy, during a first cardiac cycle, from a pulse generator to the electrode configurations. The pacing pulses are separated by pacing pulse (PP) intervals. The method and system dynamically adjust at least one of a timing or a duration of discharge pulses for the residual charge to form a discharge sequence. The method and system activate the discharge pulses based on the discharge sequence, during the first cardiac cycle, to the multiple LV electrodes to distribute the residual charge across the PP intervals.

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.