Abstract: Methods and systems are provided for determining pacing parameters for an implantable medical device (IMD). The methods and systems provide electrodes in the right atrium (RA), right ventricle (RV) and left ventricle (LV). The methods and systems sense RV cardiac signals and LV cardiac signals at an RV electrode and an LV electrode, respectively, over multiple cardiac cycles, to collect global activation information. The methods and systems identify a T-wave in the LV cardiac signal. The methods and systems calculate a repolarization index based at least in part on a timing of the T-wave identified in the LV cardiac signal. The methods and systems set at least one pacing parameter based on the repolarization index, wherein the at least one pacing parameter that is set represents at least one of an AV delay, an inter-ventricular interval and an intra-ventricular interval.

Abstract: Diastolic function is monitored within a patient using a pacemaker or other implantable medical device. In one example, the implantable device uses morphological parameters derived from the T-wave evoked response waveform as proxies for ventricular relaxation rate and ventricular compliance. In particular, the magnitude of the peak of the T-wave evoked response is employed as a proxy for ventricular compliance. The maximum slew rate of the T-wave evoked response following its peak is employed as a proxy for ventricular relaxation. A metric is derived from these proxy values to represent diastolic function. The metric is tracked over time to evaluate changes in diastolic function. In other examples, specific values for ventricular compliance and ventricular relaxation are derived for the patient based on the T-wave evoked response parameters.

Abstract: CRT settings for an implantable medical device are determined by applying pacing pulses to heart chambers of a scheme of different combinations of interchamber delays. A respective width parameter value representing an R or P wave width is determined for each such delay combination based on an ECG representing signal and the width parameter values are employed to estimate a parametric model defining the width parameter as a function of interchamber delays. Candidate interchamber delays that minimize the width parameter are determined from the parametric model and employed to determine optimal CRT settings. The technique provides an efficient way of finding optimal CRT settings when multiple pacing sites are available in a heart chamber.

Abstract: Methods for monitoring a patient's level of B-type natriuretic peptide (BNP), and implantable cardiac systems capable of performing such methods, are provided. A ventricle is paced for a period of time to provoke a ventricular evoked response, and a ventricular intracardiac electrogram (IEGM) indicative of the ventricular evoked response is obtained. Based on the ventricular IEGM, there is a determination of at least one ventricular evoked response metric (e.g., ventricular evoked response peak-to-peak amplitude, ventricular evoked response area and/or ventricular evoked response maximum slope), and the patient's level of BNP is monitored based on determined ventricular evoked response metric(s). Based on the monitored level's of BNP, the patients heart failure (HF) condition and/or risks and/or occurrences of certain events (e.g., an acute HF exacerbation and/or an acute myocardial infarction) can be monitored.

Abstract: An exemplary method includes accessing cardiac information acquired via a catheter located at various positions in a venous network of a heart of a patient where the cardiac information comprises position information, electrical information and mechanical information; mapping local electrical activation times to anatomic positions to generate an electrical activation time map; mapping local mechanical activation times to anatomic positions to generate a mechanical activation time map; generating an electromechanical delay map by subtracting local electrical activation times from corresponding local mechanical activation times; and rendering at least the electromechanical delay map to a display. Various other methods, devices, systems, etc., are also disclosed.

Abstract: An exemplary method generates a map of a pacing parameter, a sensing parameter or one or more other parameters based in part on location information acquired using a localization system configured to locate electrodes in vivo (i.e., within a patient's body). Various examples map capture thresholds, qualification criteria for algorithms, undesirable conditions and sensing capabilities. Various other methods, devices, systems, etc., are also disclosed.

Abstract: Diastolic function is monitored within a patient using a pacemaker or other implantable medical device. In one example, the implantable device uses morphological parameters derived from the T-wave evoked response waveform as proxies for ventricular relaxation rate and ventricular compliance. In particular, the magnitude of the peak of the T-wave evoked response is employed as a proxy for ventricular compliance. The maximum slew rate of the T-wave evoked response following its peak is employed as a proxy for ventricular relaxation. A metric is derived from these proxy values to represent diastolic function. The metric is tracked over time to evaluate changes in diastolic function. In other examples, specific values for ventricular compliance and ventricular relaxation are derived for the patient based on the T-wave evoked response parameters.

Abstract: In specific embodiments, a method for estimating a patient's central arterial blood pressure (CBP) for use with an implantable system, comprises (a) using an implanted sensor at a first site to obtain a first signal indicative of changes in arterial blood volume at the first site, the first site being along one or more peripheral arterial structures of the patient, (b) using an implanted sensor at a second site to obtain a second signal indicative of changes in arterial blood volume at the second site, the second site being a distance from the first site downstream along an arterial path of the peripheral arterial structure of the patient, and (c) using implanted electrodes to obtain a signal indicative of electrical activity of the patient's heart.

Abstract: Embodiments of the present invention are directed to implantable systems, and methods for use therewith, that monitor and modify a patient's arterial blood pressure without requiring an intravascular pressure transducer. In accordance with an embodiment, for each of a plurality of periods of time, there is a determination one or more metrics indicative of pulse arrival time (PAT), each of which are indicative of how long it takes for the left ventricle to generate a pressure pulsation that travels from the patient's aorta to a location remote from the patient's aorta. Based on the one or more metrics indicative of PAT, the patient's arterial blood pressure is estimated. Changes in the arterial blood pressure are monitored over time. Additionally, the patient's arterial blood pressure can be modified by initiating and/or adjusting pacing and/or other therapy based on the estimates of the patient's arterial blood pressure and/or monitored changes therein.

Abstract: An implantable medical device includes a lead configured to be located proximate to the left ventricle (LV) of the heart, the lead including multiple LV electrodes to sense cardiac activity at multiple LV sensing sites. The a detection module to detect an arrhythmia that represents at least one of a tachycardia and fibrillation based at least in part on the cardiac activity sensed at the multiple LV sensing sites. The ATP therapy module to identify at least one of an ATP configuration or an ATP therapy site based on the cardiac sensed activity at the LV sensing sites, the ATP therapy module to control delivery of antitachycardia pacing (ATP) therapy at the ATP therapy site.

Abstract: Techniques are provided for use with implantable cardiac stimulation devices equipped for multi-site left ventricular (MSLV) cardiac pacing. Briefly, intraventricular and interventricular conduction delays are detected for paced cardiac events. Maximum pacing time delays are determined for use with MSLV pacing where the maximum pacing time delays are set based on the conduction delays to values sufficient to avoid capture problems due to wavefront propagation, such as fusion or lack of capture. MSLV pacing delays are then set to values no greater than the maximum pacing delays and cardiac resynchronization therapy (CRT) is delivered using the MSLV pacing delays. In an example where an optimal interventricular pacing delay (VV) is determined in advance using intracardiac electrogram-based or hemodynamic-based optimization techniques, the optimal value for VV can be used as a limiting factor when determining the maximum MSLV pacing time delays.

Abstract: A system and method for treating an arrhythmia in a heart are provided. The system includes an electronic control unit configured to monitor movement of one or more position sensor over a period of time. The position sensors may, for example, comprise electrodes or coils configured to generate induced voltages and currents in the presence of electromagnetic fields. The positions sensors are in contact with portions of heart tissue and changes in position are representative of motion of that tissue. The electronic control unit is further configured to generate an indicator, responsive to the movements of the sensors over the period of time, of a characteristic of the heart affected by delivery of ablation energy to heart tissue. In this manner, the effectiveness and safety of cardiac tissue ablation for treatment of the arrhythmia can be assessed and a post-ablation therapy regimen determined.

Abstract: Techniques are provided for use with an implantable cardiac stimulation device equipped for multi-site left ventricular (MSLV) pacing using a multi-pole LV lead. In one example, referred to herein as QuickStim, cardiac pacing configurations are optimized based on an assessment of hemodynamic benefit and device longevity. In another example, referred to herein as QuickSense, cardiac sensing configurations are optimized based on sensing profiles input by a clinician. Various virtual sensing channels are also described that provide for the multiplexing or gating of sensed signals. Anisotropic oversampling is also described.

Abstract: An exemplary method includes providing at least two-dimensional position information, for at least two points in time, for an electrode located in a cardiac space; determining a local estimator based on the position information; and, based at least in part on the determined local estimator, selecting a configuration for delivering a cardiac pacing therapy or diagnosing a cardiac condition. Exemplary methods for regional estimators and exemplary methods for global estimators are also disclosed along with devices and systems configured to perform various methods.

Abstract: An exemplary method includes providing a mechanical activation time (MA time) for a myocardial location, the location defined at least in part by an electrode and the mechanical activation time determined at least in part by movement of the electrode; providing an electrical activation time (EA time) for the myocardial location; and determining an electromechanical delay (EMD) for the myocardial location based on the difference between the mechanical activation time (MA time) and the electrical activation time (EA time).

Abstract: Therapy optimization includes tracking electrode motion using an electroanatomic mapping system and generating, based on tracked electrode motion, one or more mechanical dyssynchrony metrics to thereby guide a clinician in therapy optimization (e.g., via optimal electrode sites, optimal therapy parameters, etc.). Such a method may include a vector analysis of electrode motion with respect to factors such as times in cardiac cycle, phases of a cardiac cycle, and therapy conditions, e.g., pacing sites, pacing parameters and pacing or no pacing. Differences in position-with-respect-to-time data for electrodes may also be used to provide measurements of mechanical dyssynchrony.

Abstract: Provided herein are implantable systems, and methods for use therewith, for monitoring a patient's pre-ejection interval (PEI). A signal indicative of cardiac electrical activity and a signal indicative of changes in arterial blood volume are obtained. One or more predetermined features of the signal indicative of cardiac electrical activity and the signal indicative of changes in arterial blood volume are detected. The patient's PEI is determined by determining an interval between the predetermined feature of the signal indicative of cardiac electrical activity and the predetermined feature of the signal indicative of changes in arterial blood volume.

Abstract: Implanted systems and methods for monitoring a patient's arterial stiffness are provided. An implanted sensor is used to produce a signal indicative of changes in arterial blood volume for a plurality of beats of the patient's heart. A pulse duration metric is determined for each of a plurality of pulses of the signal, wherein each pulse of the signal corresponds to a beat of the patient's heart. Arterial stiffness is monitored based on the determined pulse duration metric for the plurality of pulses of the signal. This can include monitoring arterial stiffness based on a dispersion of the pulse duration metric and/or an average of the pulse duration metric.

Abstract: An exemplary method includes providing a mechanical activation time (MA time) for a myocardial location, the location defined at least in part by an electrode and the mechanical activation time determined at least in part by movement of the electrode; providing an electrical activation time (EA time) for the myocardial location; and determining an electromechanical delay (EMD) for the myocardial location based on the difference between the mechanical activation time (MA time) and the electrical activation time (EA time).

Abstract: An exemplary method includes providing a mechanical activation time (MA time) for a myocardial location, the location defined at least in part by an electrode and the mechanical activation time determined at least in part by movement of the electrode; providing an electrical activation time (EA time) for the myocardial location; and determining an electromechanical delay (EMD) for the myocardial location based on the difference between the mechanical activation time (MA time) and the electrical activation time (EA time).