Method and apparatus for post-processing of episodes detected by a medical device

• US 8,073,536 B2
• Filed: 11/28/2006
• Issued: 12/06/2011
• Est. Priority Date: 11/28/2005
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Gunderson, Bruce D., Brown, Mark L., Patel, Amisha Somabhai
• Primary Examiner(s): Patel, Niketa
• Assistant Examiner(s): Holmes, Rex R
• Application Number:
  US11/564,147
• Publication Number:
  US 20070123789A1
• Time in Patent Office: 1,834 Days
• Field of Search: 607/4, 607/9, 607 27- 28, 600517-518
• US Class Current: 607/9
• CPC Class Codes: A61B 2560/0271 using a remote monitoring unit
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/35 by template matching
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371
• CPC Class Codes: A61N 1/3706 Pacemaker parameters stimulation threshold A61N1/371
• CPC Class Codes: A61N 1/37211 Means for communicating with stimulators
• CPC Class Codes: A61N 1/3925 Monitoring; Protecting
• CPC Class Codes: A61N 1/39622 Pacing therapy
• CPC Class Codes: G16H 40/67 for remote operation

Abstract

A method and system for determining undersensing during post-processing of sensing data generated by a medical device that includes transmitting a plurality of stored sensing data generated by the medical device to an access device, the stored sensing data including sensed atrial events and sensed ventricular events. The access device determines, in response to the transmitted data, instances where the medical device identified a cardiac event being detected in response to the sensing data, and determines whether one of a predetermined number of undersensing criteria have been met in response to the transmitted data.

Claims

1. A method of determining undersensing during post-processing of sensing data generated by and stored within an implantable medical device, comprising:

receiving the sensing data from the implantable medical device with an external access device, wherein the sensing data includes sensed atrial events and sensed ventricular events;

determining, with the external access device, in response to the received data instances where the implantable medical device identified a cardiac event being detected in response to the sensing data; and

determining, with the external access device, whether one of a predetermined number of undersensing criteria have been met in response to the received data, wherein determining whether one of a predetermined number of undersensing criteria have been met comprises;

calculating a median AA interval in a sliding window of a predetermined number of intervals;

comparing at least one interval within the sliding window to the median AA interval;

determining whether there are two or less intervals in the received data that are two times the median AA interval;

determining whether there are any intervals in the received data that are three times the median AA interval;

determining whether a majority of the AA intervals are regular; and

determining whether there is a depolarization on a corresponding atrial EGM signal where a corresponding expected atrial event would have occurred for any of the intervals that are two or three times the median AA interval.

2. A method of determining undersensing during post-processing of sensing data generated by and stored within an implantable medical device comprising:

receiving the sensing data from the implantable medical device with an external access device, wherein the sensing data includes sensed atrial events and sensed ventricular events;

determining, with the external access device, in response to the received data, instances where the implantable medical device identified a cardiac event being detected in response to the sensing data; and

determining, with the external access device, whether one of a predetermined number of undersensing criteria have been met in response to the received data, wherein determining whether one of a predetermined number of undersensing criteria have been met comprises;

calculating a median AA interval in a sliding window of a predetermined number of intervals;

comparing at least one interval within the sliding window to the median AA interval;

determining whether regular AA intervals are sensed for a majority of sensed atrial events;

determining whether there is only one or two depolarizations that are either three times the median AA interval or two times the median AA interval; and

determining whether there is a corresponding associated depolarization on an atrial EGM where a corresponding expected atrial event would have occurred for any of the intervals that are two or three times the median AA interval.

3. A method of determining of sensing, data generated by and stored within an implantable medical device, comprising:

receiving the sensing data from the implantable medical device with an external access device, wherein the sensing data includes sensed atrial events and sensed ventricular events;

determining with the external access device, in response to the received data instances where the implantable medical device identified a cardiac event being detected in response to the sensing data; and

determining, with the external access device whether one of a predetermined number of undersensing been met in response to the received data wherein determining whether one of a predetermined number of undersensing criteria have been met comprises;

calculating a median AA interval in a sliding window of a predetermined number of intervals;

comparing at least one interval within the sliding window to the median AA interval;

determining whether a predetermined number of the AA intervals in the received data within a predetermined range of a median of the AA intervals; and

determining, in response to an atrial EGM not being included in the received data, whether there are less than a predetermined number of intervals that are one of two times the median interval or three times the median interval.

4. A system for post-processing of sensing data associated with identification of a cardiac event, comprising:

an implantable medical device generating and storing a plurality of sensing data, wherein the sensing data includes sensed atrial events and sensed ventricular events;

an access device located externally from the medical device; and

an interface for receiving the sensing data from the implantable medical device with to the external access device, wherein the external access device determines whether one of a predetermined number of undersensing criteria have been met in response to the received data, calculates a median AA interval in a sliding window of a predetermined number of intervals, compares at least one interval within the sliding window to the median AA interval, determines whether there are two or less intervals in the received data that are one of two times the median AA interval, whether there are three times the median AA interval, whether a majority of the AA intervals are regular, and whether there is a depolarization on a corresponding atrial EGM signal where a corresponding expected atrial event would have occurred.

5. A system for past-processing of sensing data associated with identification of a cardiac event, comprising:

an implantable medical device generating and storing a plurality of sensing data wherein the sensing data includes sensed atrial events and sensed ventricular events;

an access device located externally from the medical device and an interface for receiving the sensing data from the implantable medical device with to the external access device, wherein the external access device determines whether one of a predetermined number of undersensing criteria have been met in response to the received data, calculates a median AA interval in a sliding window of a predetermined number of intervals compares at least one interval within the sliding window to the median AA interval, determines whether regular AA intervals are sensed for a majority of sensed atrial events, whether there is only one or two depolarizations that are either three times the median AA interval or two times the median AA interval, and determining whether there is a corresponding associated depolarization on an atrial EGM where a corresponding expected atrial event would have occurred for any of the intervals that are two or three times the median AA interval.

6. A system for post-processing of sensing data associated with identification of a cardiac event, comprising:

an implantable medical device generating and storing a plurality of sensing data, wherein the sensing data includes sensed atrial events and sensed ventricular events;

an access device located externally from the medical device; and

an interface for receiving the sensin data from the implantable medical device with the external access device, wherein the external access device determines whether one of a predetermined number or undersensing criteria have been met in response to the received data, calculates a median AA interval in a sliding window of a predetermined number of intervals, compares at least one interval within the sliding window to the median AA interval, determines whether a predetermined number of the AA intervals in the received data are within a predetermined range of the median of the AA intervals, and determines, in response to an atrial EGM not being included in the transmitted data, whether there are less than a predetermined number of intervals that are one of two times the median interval or and three times the median interval.