摘要:
A method and apparatus for adjusting a sensing parameter in a medical device that includes a sensing electrode sensing cardiac signals, a processor to determine an adjusting characteristic associated with the cardiac signals sensed over a predetermined sensing window, and a control unit to update the sensing parameter in response to the determined adjusting characteristic.
摘要:
A method and apparatus of updating a sensing parameter in a medical device that includes sensing cardiac signals, determining intervals in response to the sensed cardiac signals, determining interval patterns associated with the determined intervals, and updating the sensing parameter in response to the determined interval patterns.
摘要:
A method and apparatus for detecting a cardiac event in a medical device that includes sensing cardiac signals from a plurality of electrodes, the plurality of electrodes forming a first sensing vector and a second sensing vector different from the first sensing vector, determining a characteristic associated with cardiac signals sensed along the first sensing vector during a predetermined sensing window, determining the characteristic associated with cardiac signals sensed along the second sensing vector during the predetermined sensing window; comparing the determined characteristic associated with cardiac signals sensed along the first sensing vector and the determined characteristic associated with cardiac signals sensed along the second sensing vector, and delivering a therapy in response to the comparing.
摘要:
Implantable medical devices (IMDs) for detection and measurement of cardiac mechanical and electrical function employ a system and method for determining mechanical heart function and measuring mechanical heart performance of upper and lower and left and right heart chambers without intruding into a left heart chamber through use of a dimension sensor. The dimension sensor or sensors comprise at least a first sonomicrometer piezoelectric crystal mounted to a first lead body implanted into or in relation to one heart chamber that operates as an ultrasound transmitter when a drive signal is applied to it and at least one second sonomicrometer crystal mounted to a second lead body implanted into or in relation to a second heart chamber that operates as an ultrasound receiver.
摘要:
A method and apparatus are provided for improving the detection of certain cardiac rhythms by combining dual chamber interval-related detection methods with electrogram morphology analysis. A prioritized set of rules are defined wherein each rule is directed at identifying a particular arrhythmia or type of arrhythmia. Each rule includes clauses that may be related to sensed event intervals and interval patterns and at least one rule includes at least one clause relating to the EGM morphology.
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:
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:
A device-implemented software system operates a detection window and adjusts PAV as needed after confirming the presence or detection of evidence of an arrhythmia. The detection window is monitored based on a preferred length. If the detection window is shorter than required, intervals are adjusted for a specific pacing rate. Further, the software system provides means for selecting detection over pacing based on an analysis of a preferred length in the presence of evidence of an arrhythmia.
摘要:
We show how to determine whether there has been an axis shift in an electrocardiogram waveform and how to use this for filtering out bad electrocardiogram information and to modify an adaptive filter that can be used to adapt the filtering of such electrocardiogram information to make it available for determining physiologic conditions even after an axis shift.