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.

An implantable medical device includes circuitry for generating and delivering electrical stimulation therapy. A power source is included in the implantable medical device for storage of the energy for the stimulation therapy. Techniques and circuits are provided for minimizing energy losses associated with the storage of the stimulation therapy energy. The implantable medical device circuitry includes charging circuitry that is operated in at least a first mode and a second mode, such that the charging circuit is operable in one of the at least first and second modes based on whether an intrinsic cardiac event is detected. The charging circuit is operable to withhold charging the output capacitor in the first mode until a given cardiac cycle elapses without a sensed intrinsic cardiac event.

Techniques for evaluating cardiac electrical dyssynchrony are described. In some examples, an activation time is determined for each of a plurality of torso-surface potential signals. The dispersion or sequence of these activation times may be analyzed or presented to provide variety of indications of the electrical dyssynchrony of the heart of the patient. In some examples, the locations of the electrodes of the set of electrodes, and thus the locations at which the torso-surface potential signals were sensed, may be projected on the surface of a model torso that includes a model heart. The inverse problem of electrocardiography may be solved to determine electrical activation times for regions of the model heart based on the torso-surface potential signals sensed from the patient.

An apparatus for controlling conduction of an electrical signal in a heart comprises: a stimulation generating unit; a first pair and a second pair of electrodes to be arranged in relation to a location in the heart, wherein an interferential stimulation signal is formed in the location based on first and second stimulation signals received by the first and second pairs of electrodes, wherein a difference between a first frequency of the first stimulation signal and a second frequency of the second stimulation signal defines a beat frequency of the interferential stimulation signal for controlling conduction of the electrical signal; an electrical signal sensor for detecting conduction of the electrical signal; and a control unit for controlling output of the first and the second stimulation signals for controlling timing of the interferential stimulation signal in relation to the electrical signal.

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.

An intracardiac ventricular pacemaker having a motion sensor is configured to produce a motion signal including an atrial systolic event and a ventricular diastolic event indicating a passive ventricular filling phase, set a detection threshold to a first amplitude during an expected time interval of the ventricular diastolic event and to a second amplitude lower than the first amplitude after an expected time interval of the ventricular diastolic event. The pacemaker is configured to detect the atrial systolic event in response to the motion signal crossing the detection threshold and set an atrioventricular pacing interval in response to detecting the atrial systolic event.

Ventricle-from-atrium (VfA) cardiac therapy may utilize a tissue-piercing electrode implanted in the left ventricular myocardium of the patient's heart from the right atrium through the right atrial endocardium and central fibrous body. The exemplary devices and methods may determine whether the tissue-piercing electrode is achieving effective left ventricular capture. Additionally, one or more pacing parameters, or paced settings, may be adjusted in view of the effective left ventricular capture determination.

Techniques are provided for use with a pulmonary artery pressure (PAP) monitor having an implantable PAP sensor. In one example, a PAP signal is sensed that is representative of beat-by-beat variations in PAP occurring during individual cardiac cycles of the patient. The PAP monitor detects peaks within the PAP signal corresponding to valvular regurgitation within the heart, then detects mitral regurgitation (MR) based on the peaks. In other examples, the PAP monitor optimizes pacing parameters based on the PAP signal and corresponding electrical cardiac signals. Examples are provided where the PAP monitor is an external system and other examples are provided where the PAP monitor is a component of an implantable cardiac rhythm management device.

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.

An implantable medical device and medical device system for delivering a bi-ventricular pacing therapy that includes a plurality of electrodes to sense a cardiac signal, an emitting device to emit a trigger signal to control delivery of the bi-ventricular pacing, and a processor configured to compare the sensed cardiac signal associated with the delivered bi-ventricular pacing to at least one of an intrinsic beat template and an RV template associated with a morphology of RV-only pacing therapy, determine whether an offset interval associated with the bi-ventricular pacing therapy is set to a maximum offset interval level in response to the comparing, adjust the offset interval in response to the offset interval not being set to the maximum offset interval level, and generate the trigger signal to be emitted by the emitting device to subsequently deliver the bi-ventricular pacing therapy having the adjusted offset interval.