摘要:
The invention relates to devices that detect and/or treat tachyarrhythmias. The invention includes software systems that distinguish among various tachyarrhythmias in order to provide treatment for specific tachyarrhythmias. One aspect of the invention employs a methodology to provisionally detect ventricular tachycardia and/or fibrillation and thereafter apply a discrimination function to a series of measured intervals preceding the provisional detection. Discrimination is accomplished by sorting the intervals preceding provisional detection into bins corresponding to interval ranges and examining the relative distribution of the intervals within the bins.
摘要:
An implantable medical device and associated method are provided for detecting non-sustained arrhythmias and determining a metric of non-sustained arrhythmias. The metric may be used for predicting the occurrence of a sustained arrhythmia or for automatically adjusting the parameters used for detecting a sustained arrhythmia.
摘要:
In general, the disclosure relates to techniques for calculating mean impedance values and impedance variability values to detect a possible condition with a lead or device-lead pathway or connection. In one example, a device may be configured to determine an impedance value for an electrical path based on a plurality of measured impedance values for the electrical path, wherein the electrical path comprises a plurality of electrodes, and to determine an impedance variability value based on at least one of the plurality of measured impedance values. The device may be further configured to determine a threshold value based on the determined impedance value and the impedance variability value, compare a newly measured impedance value for the electrical path to the threshold value, and indicate a possible condition of the electrical path based on the comparison.
摘要:
In general, the disclosure relates to techniques for calculating mean impedance values and impedance variability values to detect a possible condition with a lead or device-lead pathway or connection. In one example, a device may be configured to determine an impedance value for an electrical path based on a plurality of measured impedance values for the electrical path, wherein the electrical path comprises a plurality of electrodes, and to determine an impedance variability value based on at least one of the plurality of measured impedance values. The device may be further configured to determine a threshold value based on the determined impedance value and the impedance variability value, compare a newly measured impedance value for the electrical path to the threshold value, and indicate a possible condition of the electrical path based on the comparison.
摘要:
Methods and/or devices for initiating an automatic adjustment of arrhythmia detection parameters (e.g., upon delivery of cardiac therapy after detection of VT/VF).
摘要:
The present disclosure is directed to generating and displaying an electrogram (EGM) summary for use by physicians or other clinicians. An implantable medical device (IMD) transmits EGM signal data for a number of cardiac episodes to an external computing device. The external computing device selects a subset of the cardiac episodes for which information or images are displayed to the user. In various examples, cardiac episodes may be selected for display based at least in part on a retrospective analysis classification of the cardiac episode.
摘要:
Techniques for determining whether a lead related condition exists based on analysis of a cardiac electrical signal associated with a non-sustained tachyarrhythmia (NST) are described. In some examples, the techniques include determining the duration of intervals between consecutive cardiac events, e.g., R-R intervals, during an NST. The techniques may further include determining one or more metrics based on the durations of the intervals during the NST. Examples of metrics include an average, a minimum, a maximum, a range, a median, a mode, or a mean. A lead related condition is identified based on the values of the one or more metrics, e.g., by comparison to respective thresholds. In some examples, an alert is provided or a therapy modification is suggested if a lead related condition is identified.
摘要:
A method for identifying and classifying various types of oversensing in implantable medical devices (IMDs), such as implantable cardioverter defibrillators (ICDs), to assist a physician in choosing corrective action to reduce the likelihood of oversensing and inappropriate therapy delivery. Far-field electrogram (EGM) signals are analyzed to detect the occurrence of R-waves, and the result is compared to the number and pattern of R-waves sensed by the IMD and indicated on the marker channel. A marker channel with more sensed R-waves than indicated by analysis of the far-field EGM indicates the presence of oversensing, including double-counting of R-waves, T-wave oversensing, lead malfunction or failure, poor lead connections, noise associated with electromagnetic interference, non-cardiac myopotentials, etc. Identification of the type of oversensing may be determined by analysis of the number and pattern of marker channel sensed R-waves with respect to the timing of the R-waves detected from the far-field EGM.
摘要:
Techniques for determining whether a lead related condition exists based on analysis of a cardiac electrical signal associated with a non-sustained tachyarrhythmia (NST) are described. In some examples, the techniques include determining the duration of intervals between consecutive cardiac events, e.g., R-R intervals, during an NST. The techniques may further include determining one or more metrics based on the durations of the intervals during the NST. Examples of metrics include an average, a minimum, a maximum, a range, a median, a mode, or a mean. A lead related condition is identified based on the values of the one or more metrics, e.g., by comparison to respective thresholds. In some examples, an alert is provided or a therapy modification is suggested if a lead related condition is identified.
摘要:
In general, the disclosure is directed to techniques for identification and remediation of oversensed cardiac events using far-field electrograms (FFEGMs). Identification of oversensed cardiac events can be used in an ICD to prevent ventricular fibrillation (VF) detection, and thereby avoid delivery of an unnecessary defibrillation shock. Alternatively, or additionally, identification of oversensed cardiac events can be used in an ICD to support delivery of bradycardia pacing during an oversensing condition. In some cases, bradycardia pacing delivered in response to detection of oversensed cardiac events may include pacing pulses from multiple vectors to provide redundancy in the event the oversensing may be due to a lead-related condition.