Abstract:
A method or system for computing and/or setting optimal cardiac resynchronization pacing parameters as derived from intrinsic conduction data is presented. The intrinsic conduction data includes intrinsic atrio-ventricular and interventricular delay intervals which may be collected via the sensing channels of an implantable cardiac device. Among the parameters which may be optimized in this manner are an atrio-ventricular delay interval and a biventricular offset interval. In one of its aspects, the invention provides for computing optimum pacing parameters for patients having some degree of AV block or with atrial conduction deficits. Another aspect of the invention relates to a pacing mode and configuration for providing cardiac resynchronization therapy to patients with a right ventricular conduction disorder.
Abstract:
A cardiac rhythm management system modulates the delivery of pacing and/or autonomic neurostimulation pulses based on heart rate variability (HRV). An HRV parameter being a measure of the HRV is produced to indicate a patient's cardiac condition, based on which the delivery of pacing and/or autonomic neurostimulation pulses is started, stopped, adjusted, or optimized. In one embodiment, the HRV parameter is used to evaluate a plurality of parameter values for selecting an approximately optimal parameter value.
Abstract:
A cardiac rhythm management system modulates the delivery of pacing and/or autonomic neurostimulation pulses based on heart rate variability (HRV). An HRV parameter being a measure of the HRV is produced to indicate a patient's cardiac condition, based on which the delivery of pacing and/or autonomic neurostimulation pulses is started, stopped, adjusted, or optimized. In one embodiment, the HRV parameter is used as a safety check to stop an electrical therapy when it is believed to be potentially harmful to continue the therapy.
Abstract:
A cardiac rhythm management system modulates the delivery of pacing and/or autonomic neurostimulation pulses based on heart rate variability (HRV). An HRV parameter being a measure of the HRV is produced to indicate a patient's cardiac condition, based on which the delivery of pacing and/or autonomic neurostimulation pulses is started, stopped, adjusted, or optimized. In one embodiment, the HRV parameter is used to evaluate a plurality of parameter values for selecting an approximately optimal parameter value.
Abstract:
Systems and methods involve determination of CRT parameters using a number of CRT optimization processes. Each CRT optimization process attempts to return recommended parameters. The CRT parameters are determined based on the recommended parameters returned by one or more of the CRT optimization processes. The CRT optimization processes may be sequentially implemented and the CRT parameters may be determined based on the recommended parameters returned by a first CRT optimization process to return recommended parameters. The CRT parameters may be determined based on a combination of the recommended parameters returned. The CRT optimization processes implemented may be selected from available CRT optimization processes based on patient conditions.
Abstract:
A method and system for calculating an atrio-ventricular delay interval based upon an inter-atrial delay exhibited by a patient's heart. The aforementioned atrio-ventricular delay interval may optimize the stroke volume exhibited by a patient's heart. The aforementioned atrio-ventricular delay interval may be blended with another atrio-ventricular delay interval that may optimize another performance characteristic, such as left ventricular contractility. Such blending may include finding an arithmetic mean, geometric mean, or weighted mean of two or more proposed atrio-ventricular delay intervals.
Abstract:
A method and system for determining an optimum atrioventricular delay (AVD) interval and/or ventriculo-ventricular delay (VVD) intervals for delivering ventricular resynchronization pacing in an atrial tracking or atrial sequential pacing mode. Evoked response electrograms recorded at different AVD and VVD intervals are used to determine the extent of paced and intrinsic activation.
Abstract:
Method and systems related to monitoring right ventricular function during pacing by a cardiac rhythm management device are described. One or more pacing parameters are selected to provide cardiac resynchronization therapy. For example, the one or more pacing parameters may be selected to provide an optimal or improved therapy. The heart is paced using the selected pacing parameters. While pacing with the selected parameters, pressure is sensed via a pressure sensor disposed the pulmonary artery. The sensed pressure is analyzed to determine right ventricular function achieved during the pacing using the selected pacing parameters. A signal, such as an alert signal or control signal, is generated based on the right ventricular function achieved during the pacing.
Abstract:
Cardiac monitoring and/or stimulation methods and systems that provide one or more of monitoring, diagnosing, defibrillation, and pacing. Cardiac signal separation is employed for automatic capture verification using cardiac activation sequence information. Devices and methods sense composite cardiac signals using implantable electrodes. A source separation is performed using the composite signals. One or more signal vectors are produced that are associated with all or a portion of one or more cardiac activation sequences based on the source separation. A cardiac response to the pacing pulses is classified using characteristics associated with cardiac signal vectors and the signals associated with the vectors. Further embodiments may involve classifying the cardiac response as capture or non-capture, fusion or intrinsic cardiac activity. The characteristics may include an angle or an angle change of the cardiac signal vectors, such as a predetermined range of angles of the one or more cardiac signal vectors.
Abstract:
This document discusses, among other things, systems, devices, and methods measure an impedance and, in response, adjust an atrioventricular (AV) delay or other cardiac resynchronization therapy (CRT) parameter that synchronizes left and right ventricular contractions. A first example uses parameterizes a first ventricular volume against a second ventricular volume during a cardiac cycle, using a loop area to create a synchronization fraction (SF). The CRT parameter is adjusted in closed-loop fashion to increase the SF. A second example measures a septal-freewall phase difference (PD), and adjusts a CRT parameter to decrease the PD. A third example measures a peak-to-peak volume or maximum rate of change in ventricular volume, and adjusts a CRT parameter to increase the peak-to-peak volume or maximum rate of change in the ventricular volume.