摘要:
In an example, a cardiac rhythm management system includes an implantable physiological data monitor, a processor, a memory, and a display. The implantable physiological data monitor can be configured to monitor a plurality of cardiac responses. The processor can be configured to classify the cardiac response into one of at least three classes including pace-dominant, fusion, and pseudo-fusion. The processor can also be configured to calculate statistical information regarding the classified cardiac responses. In this example, the pace-dominant, fusion, and pseudo-fusion classes correspond to a cardiac response resulting from a corresponding electrostimulation. The memory is configured to store the classified cardiac responses and calculated statistical information for future use by the processor or for display. The display is configured to display the statistical information stored in the memory for diagnostic and device programming purposes.
摘要:
A neurostimulation system measures a cardiac parameter at various cardiac intervals and analyzes its restitution, including computing a restitution slope being a rate of change of the restitution parameter with respect to change in the cardiac interval. In various embodiments, the system uses the restitution slope to provide for adaptive control of neurostimulation. In various embodiments, one or more cardiac parameters such as action potential duration (APD), conduction velocity (CV), QT interval (QT), and/or T-wave morphology (TM) parameter are measured and analyzed for restitution of each parameter, which is then used to control the delivery of the neurostimulation.
摘要:
A system comprises a cardiac signal sensing circuit and a processor circuit. To detect a QRS duration, the processor circuit determines an isoelectric amplitude value of the cardiac signal segment, identifies a time where the cardiac signal segment amplitude deviates from the first isoelectric amplitude value by a specified threshold deviation value as a Q time, determines an isoelectric value time after the determined maxima and minima times that the cardiac signal segment returns to the same or a different isoelectric amplitude value, identifies a time that follows both the determined maxima and minima times and precedes the isoelectric value time as an S time, wherein the cardiac signal segment amplitude at the identified S time satisfies a specified amplitude change criterion from an isoelectric amplitude value, and determines a time duration of the QRS complex in the cardiac signal segment using the identified Q and S times.
摘要:
This document discusses, among other things, a system and method for generating a stimulation energy to provide His-bundle stimulation for a cardiac cycle, receiving electrical information from the heart over at least a portion of the cardiac cycle, determining a characteristic of at least a portion of the received electrical information for the cardiac cycle, and classifying the cardiac cycle using the determined characteristic.
摘要:
A system comprises a cardiac signal sensing circuit and a processor circuit. To detect a QRS duration, the processor circuit determines an isoelectric amplitude value of the cardiac signal segment, identifies a time where the cardiac signal segment amplitude deviates from the first isoelectric amplitude value by a specified threshold deviation value as a Q time, determines an isoelectric value time after the determined maxima and minima times that the cardiac signal segment returns to the same or a different isoelectric amplitude value, identifies a time that follows both the determined maxima and minima times and precedes the isoelectric value time as an S time, wherein the cardiac signal segment amplitude at the identified S time satisfies a specified amplitude change criterion from an isoelectric amplitude value, and determines a time duration of the QRS complex in the cardiac signal segment using the identified Q and S times.
摘要:
A neurostimulation system measures a cardiac parameter at various cardiac intervals and analyzes its restitution, including computing a restitution slope being a rate of change of the restitution parameter with respect to change in the cardiac interval. In various embodiments, the system uses the restitution slope to provide for adaptive control of neurostimulation. In various embodiments, one or more cardiac parameters such as action potential duration (APD), conduction velocity (CV), QT interval (QT), and/or T-wave morphology (TM) parameter are measured and analyzed for restitution of each parameter, which is then used to control the delivery of the neurostimulation.
摘要:
A system comprises a cardiac signal sensing circuit and a processor circuit. The cardiac signal sensing circuit is configured to sense a cardiac signal segment using a set of electrodes connectable to the cardiac signal sensing circuit. The processor circuit is communicatively coupled to the cardiac signal sensing circuit and includes a peak detector circuit. The peak detector circuit is configured to identify, in the cardiac signal segment, a fiducial indicative of ventricular activation that is local to at least one electrode of the first set of electrodes. The fiducial includes a first large positive or negative peak greater than a specified percentage of a maximum peak of the first cardiac signal segment. The processor circuit is configured to provide an indication of local ventricular activation to at least one of a user or process.
摘要:
A method and device to detect and compare changes in atrial rate and morphology can be used to identify left atrial sense and capture, such as from a quadripolar or other lead located in or around the coronary sinus.
摘要:
An apparatus comprises an ambulatory cardiac signal sensing circuit configured to provide an electrical cardiac signal representative of cardiac activity of a subject and processor. The processor includes a feature module, a correlation module, and an ischemia detection module. The feature module is configured to identify a fiducial feature in the cardiac signal and locate one or more cardiac features in the cardiac signal using the fiducial feature. The correlation module is configured to calculate a measure of similarity of morphology for a segment of the cardiac signal that includes the cardiac features. The ischemia detection module is configured to detect a change in the measure of similarity and determine whether the detected change in the measure of similarity is indicative of ischemia.
摘要:
Approaches to rank potential left ventricular (LV) pacing vectors are described. Early elimination tests are performed to determine the viability of LV cathode electrodes. Some LV cathodes are eliminated from further testing based on the early elimination tests. LV cathodes identified as viable cathodes are tested further. Viable LV cathode electrodes are tested for hemodynamic efficacy. Cardiac capture and phrenic nerve activation thresholds are then measured for potential LV pacing vectors comprising a viable LV cathode electrode and an anode electrode. The potential LV pacing vectors are ranked based on one or more of the hemodynamic efficacy of the LV cathodes, the cardiac capture thresholds, and the phrenic nerve activation thresholds.