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.

The disclosure relates to a device including a plurality of electrodes for stimulation of both ventricles with application of an atrioventricular delay and of an interventricular delay, a processor configured to multidimensionally measure an interventricular conduction delay, and monitor the evolution of a patient's condition. For the multidimensional measurement of the interventricular conduction delay, the device produces stimulation of one of the ventricles and collects, in the other ventricle, two endocardial electrogram signals on separate respective channels, giving two respective temporal components. Both temporal components are combined in one single parametric 2D characteristic representative of the cardiac cycle, and a comparison is made with reference descriptors for deriving an index representative of the evolution of the patient's condition.

Embodiments of the present technology described herein are directed to implantable systems for performing cardiac resynchronization therapy (CRT), methods for use therewith, and leadless pacemakers for use therewith. Such a system can include a first leadless pacemaker configured to be implanted in or on the right atrial (RA) chamber and selectively pace the RA chamber, a second leadless pacemaker configured to be implanted in or on the right ventricular (RV) chamber and selectively pace the RV chamber, and a third leadless pacemaker configured to be implanted in or on the left ventricular (LV) chamber and selectively pace the LV chamber, wherein one of the leadless pacemaker is designated a master leadless pacemaker. In certain embodiments, the master leadless pacemaker determines a VV delay and an AV delay and coordinates CRT using such delays.

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.

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.

An apparatus includes a relay and sampling unit, a pacing unit, a pacing detection circuit, and a processor. The relay and sampling unit receives multiple electrocardiogram (ECG) signals that are sensed by respective electrodes in a heart of a patient, and digitize a first subset of the ECG signals, and forward a second subset of the ECG signals un-digitized over analog lines. The pacing unit outputs pacing signals, which the pacing detection circuit detects and outputs a trigger in response. The processor receives the trigger and identities of ones of the electrodes via which the pacing signals are to be applied, and, in response to identifying that the electrodes, via which the pacing signals are to be applied, are currently associated with the digitized ECG signals, instructs the relay and sampling unit to switch the identified electrodes to the analog lines for transferring the pacing signals.

A method, system and device for monitoring and treating conditions of a mammalian heart, among which may include bradyarrhythmias, tachyarrhythmias and heart failure, the device being configured as a pacemaker that harvests energy as it implements the pacemaker functions to treat and monitor conditions of the heart. The pacemaker has a case, electrical circuitry sealed within the case, an electrode that is electrically coupled to the electrical circuitry, and embodiments may include a microelectromechanical system (MEMS) for harvesting and converting the kinematic energy of the heart into electrical energy. Embodiments provide receivers at locations of the heart which sense heart activity and are controlled with pacing circuitry to deliver electrical impulses at locations and time intervals to replicate the contractions of a normal functioning heart. Further embodiments provide a multi-part pacemaker where case-connectable electrode part may be implanted separately from the case part.

An apparatus includes a relay and sampling unit, a pacing unit, a pacing detection circuit, and a processor. The relay and sampling unit receives multiple electrocardiogram (ECG) signals that are sensed by respective electrodes in a heart of a patient, and digitize a first subset of the ECG signals, and forward a second subset of the ECG signals un-digitized over analog lines. The pacing unit outputs pacing signals, which the pacing detection circuit detects and outputs a trigger in response. The processor receives the trigger and identities of ones of the electrodes via which the pacing signals are to be applied, and, in response to identifying that the electrodes, via which the pacing signals are to be applied, are currently associated with the digitized ECG signals, instructs the relay and sampling unit to switch the identified electrodes to the analog lines for transferring the pacing signals.

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.

The present disclosure pertains to cardiac pacing methods and systems, and, more particularly, to cardiac resynchronization therapy (CRT). In particular, the present disclosure pertains to determining whether a patient is experiencing atrial fibrillation (AF). If the patient is experiencing AF, the efficacy of CRT is determined. A signal is sensed in response to a ventricular pacing stimulus. Through signal processing, a number of features are parsed from the signal and a determination is made as to whether the ventricular pacing stimulus evoked a response from the ventricle.