An implantable medical device (IMD) is configured with a pressure sensor. The IMD includes a housing and a diaphragm that is exposed to the environment outside of the housing. The diaphragm is configured to transmit a pressure from the environment outside of the housing to a piezoelectric membrane. In response, the piezoelectric membrane generates a voltage and/or a current, which is representative of a pressure change applied to the housing diaphragm. In some cases, only changes in pressure over time are used, not absolute or gauge pressures.

A method of operating a cardiac rhythm management (CRM) system includes measuring a baseline PR interval of a cardiac depolarization; measuring one or both of a heart sound and a QRS width for the cardiac depolarization; delivering pacing stimulation according to an atrial sense to ventricular pace interval (AsVp interval) and measuring the one or both of the heart sound and the QRS width for the AsVp interval, wherein the pacing stimulation is delivered using a conduction system pacing (CSP) vector that includes an electrode positioned in an interventricular septum; delivering pacing stimulation according to an atrial pace to ventricular pace interval (ApVp interval) and measuring the one or both of the heart sound and the QRS width for the ApVp interval; and generating a recommended atrial to ventricular delay setting for CSP according to the measured one or both of the heart sounds and the QRS widths.

An intracardiac pacemaker system is configured to produce physiological atrial event signals by a sensing circuit of a ventricular intracardiac pacemaker and select a first atrial event input as the physiological atrial event signals. The ventricular intracardiac pacemaker detects atrial events from the selected first atrial event input, determines if input switching criteria are met, and switches from the first atrial event input to a second atrial event input in response to the input switching criteria being met. The second atrial event input includes broadcast atrial event signals produced by a second implantable medical device and received by the ventricular intracardiac pacemaker.

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 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 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.

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.

The invention consists of a device and method for the prediction of left ventricular ejection fraction (EF) and other cardiac hemodynamic parameters using systolic time intervals in patients with narrow QRS, right bundle branch block, left bundle branch block, right ventricular and/or left ventricular cardiac pacing and in the presence of arrhythmia, such as atrial fibrillation. The device has three inputs: the ECG, a peripheral pulse and a phonocardiogram. Timing parameters are obtained from these signals to calculate a systolic function index, used for the prediction of ejection fraction. Given the invention's features it would be now possible to assess cardiac performance and specifically left ventricular ejection fraction in ambulatory patients as well as during invasive procedures such as the implant of cardiac rhythm management devices. Also, an implantable embodiment of the invention would allow constant monitoring of cardiac performance, parameter adjustment of cardiac devices and automatic drug infusion.

Methods, systems and devices for providing cardiac resynchronization therapy (CRT) to a patient using a leadless cardiac pacemaker and an extracardiac device. The extracardiac device is configured to analyze one or more QRS complexes of the patient's heart, determine whether fusion pacing is taking place, and, if not, to communicate with the leadless cardiac pacemaker to adjust intervals used in the CRT in order to generate desirable fusion of the pace and intrinsic signals. The extracardiac device may take the form of a subcutaneous implantable monitor, a subcutaneous implantable defibrillator, or other devices including wearable devices.

A medical device for treating cardiac arrhythmia is disclosed, including: a microprocessor (8) and a digital/analog module (9). A MCU (1) configures the medical device to operate in a modified DVI (R) mode in which: when receiving a signal indicating the sensing of an atrial event by a sense control/amplification unit (6), the MCU (1) sets a PANP interval and sends to a time control unit (2) a signal, controlling a first timing unit (11) to operate in a timing mode for a duration equal to a duration of the PANP interval; if a scheduled post-ventricular atrial escaping interval is to end at a time not within the PANP internal, the MCU (1) sends respective signals to a pacing control/generation unit (5) and the time control unit (2) to dictate the pacing control/generation unit (5) to deliver a pacing pulse and control a second timing unit (12) to use a PAVI as a next ventricular escape interval; and if the scheduled post-ventricular atrial escaping interval is to end within the PANP interval, the MCU (1) sends a signal to the time control unit (2), controlling the second timing unit (12) to use the PAVI as the next ventricular escape interval.

The invention relates to an active implantable pacemaker. The device analyzes a ventricular electrogram signal (EGM) and is able to recognize, in a search window, an EA4 component of endocardial acceleration (EA) associated with atrial activity. In the presence of atrioventricular conduction, the search window is determined based on the temporal position of the EA1 and/or EA2 components of the EA signal. In the absence of atrioventricular conduction, a delay is counted from a paced ventricular event and applied to mask the EA1 and/or EA2 components in the EA signal, and the window for research of the EA4 component follows the masking delay. In the presence of a confirmed EA4 component, an atrioventricular delay is applied, counted from the EA4 component, and in the opposite case a predetermined escape interval is applied, counted from the last stimulated ventricular event.