Cardiac signal template generation using waveform clustering

• US 20060247707A1
• Filed: 04/28/2005
• Published: 11/02/2006
• Est. Priority Date: 04/28/2005
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Meyer, Scott A., Dong, Yanting
• Granted Patent: US 7,499,751 B2
• Time in Patent Office: Days
• US Class Current: 607/28
• CPC Class Codes: A61B 5/35 by template matching
• CPC Class Codes: A61N 1/371 Capture, i.e. successful stimulation

Abstract

Cardiac devices and methods using cardiac waveform clustering for template generation are described. A method of characterizing a cardiac response involves delivering pacing pulses to heart, the pulses having an energy greater than a capture threshold. Cardiac signals are sensed following the pulses. Cardiac signal characteristics, waveforms, and/or features are clustered into a plurality of clusters. A cardiac response template is formed using one or more of the plurality of clusters.

Claims

1. A method of characterizing a cardiac response to pacing, comprising:

delivering pacing pulses to a heart sufficient in energy to effect capture;

sensing cardiac signals respectively following delivery of the pacing pulses;

clustering the one or more cardiac signals to define a plurality of clusters; and

forming a cardiac response template using a selected one or more of the plurality of clusters.

2. The method of claim 1, wherein clustering the cardiac signals to define the plurality of clusters comprises:

detecting one or more features of the cardiac signals; and

clustering the one or more features of the cardiac signals.

3. The method of claim 2, wherein clustering the one or more features of the cardiac signals comprises clustering the one or more features in batch mode.

4. The method of claim 2, wherein clustering the one or more features of the cardiac signals comprises clustering the one or more features beat-by-beat.

5. The method of claim 2, wherein detecting the one or more features comprises detecting peak times and peak amplitudes of the cardiac signals.

6. The method of claim 5, wherein detecting the peak times and the peak amplitudes of the cardiac signals comprises detecting peak times associated with negative polarity peaks.

7. The method of claim 5, wherein detecting the peak times and the peak amplitudes of the cardiac signals comprises detecting peak times associated with positive polarity peaks.

8. The method of claim 1, wherein forming the cardiac response template using the selected one or more of the plurality of clusters comprises forming the cardiac response template using a cluster associated with a greatest number of cardiac signals having similar characteristics.

9. The method of claim 1, wherein forming the cardiac response template using the selected one or more of the plurality of clusters comprises forming one or more detection windows using the selected one or more of the plurality of clusters.

10. The method of claim 9, further comprising determining a cardiac response to a pacing pulse using the detection windows.

11. The method of claim 10, wherein determining the cardiac response to the pacing pulse using the detection windows comprises detecting capture.

12. The method of claim 10, wherein determining the cardiac response to the pacing pulse using the detection windows comprises detecting fusion.

13. A system for characterizing one or more types of cardiac pacing response, comprising:

a pulse generator configured to deliver pacing pulses to a heart sufficient in energy to effect capture;

a sensor system configured to sense cardiac signals respectively following delivery of the pacing pulses;

a processor, coupled to the sensor system, the processor configured to cluster the cardiac signals to define a plurality of clusters and to form a cardiac response template using a selected one or more of the plurality of clusters.

14. The system of claim 13, wherein the processor is configured to detect features of the cardiac signals and to cluster the features based on a similarity of the cardiac signal features.

15. The system of claim 14, wherein the one or more features comprise peak times and peak amplitudes.

16. The system of claim 13, wherein the processor is configured to generate a plurality of initial templates and to selectively adjust at least one of the plurality of initial templates using selected ones of the cardiac signals.

17. The system of claim 13, wherein the processor is configured to form the plurality of clusters based on similarities of the cardiac signals.

18. The system of claim 13, wherein the cardiac response template comprises one or more detection windows.

19. The system of claim 13, wherein the processor is configured to determine a cardiac pacing response using the cardiac response template.

20. A cardiac system, comprising:

a pulse generator configured to deliver pacing pulses to a heart sufficient in energy to effect capture;

a sensing system configured to sense cardiac signals respectively following delivery of the pacing pulses;

means for clustering the cardiac signals to define a plurality of clusters; and

means for forming a cardiac response template using a selected one or more of the plurality of clusters.

21. The system of claim 20, further comprising:

means for extracting features of the cardiac signals; and

means for clustering the extracted features to define a plurality of clusters; and

means for forming the cardiac response template using a selected one or more of the plurality of clusters.