In some examples, a computing apparatus may determine information corresponding to a data structure and indicating delays associated with an atrium lead, a left ventricle (LV) lead, and a right ventricle (RV) lead based on one or more input variables. The computing apparatus may determine a plurality of individualized characteristics based on the information corresponding to the data structure. The computing apparatus may receive, from the plurality of measurement electrodes, a plurality of second sets of electrical measurements indicating second electrical signals applied to the patient's heart based on the plurality of individualized characteristics. The computing apparatus may determine cardiac resynchronization index (CRI) values using a first set of electrical measurements (e.g., native measurements) and the plurality of second sets of electrical measurements. The computing apparatus may generate a graphical representation based on a populated data structure and cause display of the graphical representation.

A method and implantable medical device system for delivering a left ventricular (LV) cardiac pacing therapy via a single-pass coronary sinus lead and sensing far-field cardiac signals via one or more far-field sensing vectors formed between the plurality of electrodes. Beat morphologies corresponding to the far-field cardiac signals are determined, and a beat morphology match between each of the far-field beat morphologies and an intrinsic beat morphology template is determined so that one of loss of LV capture, pseudo fusion and loss of synchrony is determined in response to the determined beat morphology match. One of a loss of capture adjustment, a pseudo fusion adjustment, and a resynchronization adjustment is performed in response to the determined one of loss of LV capture, pseudo fusion and loss of synchrony in response to the determined beat morphology match to generate an adjusted LV cardiac pacing therapy.

Systems and methods are described herein related to the evaluation and adjustment of left bundle branch (LBB) pacing therapy. Evaluation of the LBB pacing therapy may utilize electrical activity monitored from a plurality of external electrodes. The electrical activity may be used to provided one or more metrics of dispersion of surrogate cardiac electrical activation times, which may then be used to evaluate, and potentially adjust the LBB pacing therapy.

An implantable device and associated method for delivering multi-site pacing therapy is disclosed. The device comprises a set of electrodes including a first and second left ventricular electrodes spatially separated from one another and a right ventricular electrode, all coupled to an implantable pulse generator. The processing circuit coupled to the implantable pulse generator, the processing circuit configured to determine whether a prospective heart failure condition has occurred and if so to trigger the pulse generator to switch from a first pacing mode to a second pacing mode, the first pacing mode comprising delivering only a first pacing pulse to a left ventricle (LV) and thereafter delivering an RV pacing pulse to the right ventricular electrode within a single cardiac cycle and the second pacing mode comprising delivering first and a second pacing pulses to the LV and thereafter delivering an RV pacing pulse to the right ventricular electrode within a single cardiac cycle.

Various aspects of the present disclosure are directed toward apparatuses, systems, and methods for pacing a HIS bundle of a patient. The apparatuses, systems, and methods may include applying stimulation energy through one or more of a plurality of electrodes to direct a stimulation locus and pace a HIS bundle of a patient.

A system is provided for controlling a left univentricular (LUV) pacing therapy using an implantable medical device (IMD). The system also includes one or more processors configured to determine an atrial-ventricular (AV) conduction interval (AR.sub.RV) between the A site and a first RV sensed event at the RV site, determine an inter-ventricular (VV) conduction interval (R.sub.LV-R.sub.RV) between a paced event at the LV site and a second RV sensed event at the RV site, and set a ventricular refractory period (VRP) based on at least one of the AV conduction interval or the VV conduction interval and a predetermined offset. The one or more processors are also configured to blank signals over the RV sensing channel during the VRP.

Methods and devices herein are provided for managing atrial (A) pacing in connection with premature atrial contracts (PAC). The methods and devices obtain an atrial pace-on-PAC (APAC) interval and cardiac activity (CA) signals. The methods and devices are configured to: i) during a first cardiac beat; following a ventricular paced (VP) or ventricular sensed (VS) event, activate a timer for a post ventricular-atrial refractory period (PVARP) interval; and determine whether a first atrial refractory (AR) event occurs during the PVARP interval; ii) during a second cardiac beat; in response to the detecting that the first AR event occurred, initiate an APAC interval; during the APAC interval for the second cardiac beat, determine whether a second AR event occurs; and update a count of APAC events when the second AR event occurs; and iii) repeat i) and ii) for multiple cardiac beats, to track the count of APAC events.

A medical device is configured to sense a cardiac signal that includes far field ventricular event signals and determine a ventricular activity metric from the sensed cardiac signal. The ventricular activity metric may be representative of a ventricular rate or an atrioventricular time interval. The medical device is configured to determine an atrioventricular synchrony metric based on the ventricular activity metric and generate an output based on the atrioventricular synchrony metric. The device may include a memory configured to store data corresponding to the atrioventricular synchrony metric.

Systems and methods are described for subject rehospitalization management. In an example, multiple physiologic signals can be obtained from a subject using multiple sensors. In response to a hospitalization event, pre-hospitalization characteristics of the multiple physiologic signals can be identified. Post-hospitalization characteristics of the multiple physiologic signals can be identified, including characteristics that differ from their corresponding pre-hospitalization characteristics. Later subsequent physiologic signals can be further monitored after the hospitalization event, such as using the same multiple sensors, and subsequent physiologic signal characteristics can be identified. In an example, a heart failure diagnostic indication can be determined using information about the pre-hospitalization characteristics, the post-hospitalization characteristics, and the subsequent characteristics. Information about relative changes in signal characteristics from multiple sensors can be used to identify particular subject physiologic signals to monitor during subsequent periods.

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.