Differentiating arrhythmic events having different origins

• US 20070112276A1
• Filed: 11/14/2005
• Published: 05/17/2007
• Est. Priority Date: 11/14/2005
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Simms, Howard
• Granted Patent: US 8,046,060 B2
• Time in Patent Office: Days
• US Class Current: 600/515
• CPC Class Codes: A61B 5/361 Detecting fibrillation
• CPC Class Codes: A61B 5/363 Detecting tachycardia or bradycardia
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: G16H 40/63 for local operation
• CPC Class Codes: G16H 40/67 for remote operation
• CPC Class Codes: G16H 50/20 for computer-aided diagnosis, e.g. based on medical expert systems
• CPC Class Codes: G16H 70/20 relating to practices or guidelines

Abstract

Methods, systems, and computer program products differentiate between arrhythmic events having different origins. An implantable medical device detects the arrhythmic events. At least one method involves receiving electrograms representing arrhythmic events and sorting the arrhythmic events into groups based on similarities between the electrograms and/or differences between the electrograms. The method also involves identifying an exemplary arrhythmic event from each group to represent the group from which the exemplary arrhythmic event is identified and distinguishing each exemplary arrhythmic event via an interface display.

Claims

1. A method for differentiating arrhythmic events having different origins, wherein the arrhythmic events are detected in a patient by an implantable medical device, the method comprising:

receiving electrograms that represent arrhythmic events detected by the implantable medical device;

sorting the arrhythmic events into groups based on at least one of similarities between the electrograms or differences between the electrograms;

identifying an exemplary arrhythmic event from each group to represent the group from which the exemplary arrhythmic event is identified; and

distinguishing each exemplary arrhythmic event via an interface display.

2. The method of claim 1, further comprising:

comparing the exemplary arrhythmic event to classified stock arrhythmic events; and

classifying the exemplary arrhythmic event as a type of rhythm based on comparing the exemplary arrhythmic event to the classified stock arrhythmic events.

3. The method of claim 2, wherein classifying the exemplary arrhythmic event includes calculating a probability that the exemplary arrhythmic event is of the type of rhythm.

4. The method of claim 3, wherein the type of rhythm comprises one of the following:

monomorphic tachycardia;

polymorphic tachycardia;

supraventricular tachycardia;

junctional rhythm;

flutter;

fibrillation; and

standstill.

5. The method of claim 3, wherein the type of rhythm comprises a polymorphic rhythm or a monomorphic rhythm.

6. The method of claim 1, wherein receiving the electrograms comprises:

saving at least one of an onset electrogram or a pre-attempt electrogram to a designated location in response to detecting an arrhythmia; and

capturing at least one of the following;

a signal just prior to detecting the arrhythmia;

a signal during the arrhythmia; and

a signal just prior to a first therapy delivery since the arrhythmia was detected.

7. The method of claim 1, wherein sorting the arrhythmic events into groups comprises:

comparing the electrogram representing an arrhythmic event with one or more electrograms representing other arrhythmic events;

determining whether the electrogram is substantially similar to any of the electrograms representing other arrhythmic events;

in response to the electrogram being substantially similar, associating the electrogram representing the arrhythmic event with other electrograms in a group of electrograms with substantially similar waveforms; and

in response to the electrogram not being substantially similar to any electrograms representing other arrhythmic events, establishing a new group of arrhythmic events detected by the implantable medical device and represented by the electrogram.

8. The method of claim 7, wherein comparing the electrogram with one or more electrograms representing other arrhythmic events utilizes at least one of the following techniques:

cross correlation of signals;

signal transform comparison;

mean squared error comparison of signals; and

user-specified comparison criteria.

9. The method of claim 7, wherein sorting the arrhythmic event further comprises at least one of the following:

comparing a heart rate associated with the arrhythmic event to heart rates associated with other arrhythmic events represented by electrograms and associating the arrhythmic event in a group based on heart rate similarities;

comparing detection state variable values during the arrhythmic event to detection state variable values during other arrhythmic events represented by electrograms and associating the arrhythmic event in a group based on similarities between the detection state variable values;

comparing a quantity of therapies and type of therapy delivered in response to the arrhythmic event to quantities of and types of therapies delivered in response to other arrhythmic events represented by electrograms and associating the arrhythmic event in a group based on similarities between the quantities and types of therapy delivered.

10. The method of claim 1, wherein identifying an exemplary arrhythmic event from each group comprises selecting an exemplary electrogram from each group.

11. The method of claim 1, wherein identifying an exemplary arrhythmic event from each group comprises selecting exemplary descriptive text describing each group.

12. The method of claim 10, wherein distinguishing each exemplary arrhythmic event via an interface display comprises one of the following:

highlighting each exemplary electrogram among other electrograms via the interface display; and

displaying only each exemplary electrogram via the interface display.

13. The method of claim 11, wherein distinguishing each exemplary arrhythmic event via an interface display comprises one of the following:

highlighting the exemplary descriptive text for each group among other descriptive text via the interface display; and

displaying only the exemplary descriptive text for each group via the interface display.

14. The method of claim 6, wherein detecting an arrhythmia comprises detecting an atrial tachycardia response (ATR).

15. A computer program product comprising a computer-readable medium having control logic stored therein for causing a computing apparatus to differentiate between arrhythmic events detected in a patient, the control logic comprising computer-readable program code for causing the computing apparatus to:

receive electrograms representing arrhythmic events;

sort the arrhythmic events into groups based on similarities between the electrograms;

identify an exemplary arrhythmic event from each group to represent the group from which the exemplary arrhythmic event is identified; and

distinguish each exemplary arrhythmic event via an interface display.

16. The computer program product of claim 15, further comprising computer-readable program code for causing the computing apparatus to:

compare the exemplary arrhythmic event to classified stock arrhythmic events; and

classify the exemplary arrhythmic event as a type of rhythm based on comparing the exemplary arrhythmic event to the classified stock arrhythmic events.

17. The computer program product of claim 15, wherein the computer-readable program code for causing the computing apparatus to sort the arrhythmic events into groups comprises computer-readable program code for causing the computing apparatus to:

compare the electrogram representing an arrhythmic event with one or more electrograms representing other arrhythmic events;

determine whether the electrogram is substantially similar to any of the electrograms representing other arrhythmic events;

in response to the electrogram being substantially similar, associate the electrogram representing the arrhythmic event with other electrograms in a group of electrograms with substantially similar waveforms; and

in response to the electrogram not being substantially similar to any electrograms representing other arrhythmic events, establish a new group of arrhythmic events represented by the electrogram.

18. A computer-implemented system for differentiating between arrhythmic events having different origins, wherein the arrhythmic events are detected in a patient by an implantable medical device, the system comprising:

an external programmer operative to;

receive electrograms that represent arrhythmic events detected by the implantable medical device;

sort the arrhythmic events into groups based on at least one of similarities between the electrograms or differences between the electrograms;

identify an exemplary arrhythmic event from each group to represent the group from which the exemplary arrhythmic event is identified; and

distinguish each exemplary arrhythmic event via an interface display.

19. The system of claim 18, further comprising a patient management system operative to:

receive the exemplary arrhythmic events representing the groups;

compare each exemplary arrhythmic event to classified stock arrhythmic events stored in a database; and

classify each exemplary arrhythmic event as a type of rhythm based on comparing the exemplary arrhythmic events to the classified stock arrhythmic events.

20. The system of claim 18, wherein the external programmer operative to distinguish each exemplary arrhythmic event via the interface display is operative to one of the following:

highlight each exemplary electrogram among other electrograms via the interface display;

display each exemplary electrogram via the interface display;

highlight exemplary descriptive text among other descriptive text via the interface display; and

display the exemplary descriptive text for each group via the interface display.