Capture detection for multi-chamber pacing

• US 8,116,870 B2
• Filed: 06/23/2008
• Issued: 02/14/2012
• 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: Dong, Yanting, Meyer, Scott A., Stahlsberg, Kevin John
• Primary Examiner(s): Schaetzle, Kennedy
• Application Number:
  US12/214,852
• Publication Number:
  US 20090069858A1
• Time in Patent Office: 1,331 Days
• Field of Search: None
• US Class Current: 607/28
• CPC Class Codes: A61N 1/3684 for stimulating the heart at multiple sites of the ventricle or the atrium
• CPC Class Codes: A61N 1/36843 Bi-ventricular stimulation
• CPC Class Codes: A61N 1/3712 Auto-capture, i.e. automatic adjustment of the stimulation threshold

Abstract

Multi-chamber pacing may result in capture of one chamber, capture of multiple chambers, fusion, or non-capture. Approaches for detecting various capture conditions during multi-chamber pacing are described. Pacing pulses are delivered to left and right heart chambers during a cardiac cycle. A cardiac electrogram signal is sensed following the delivery of the pacing pulses. Left chamber capture only, right chamber capture only, and bi-chamber capture may be distinguished based on characteristics of the cardiac electrogram signal. Multi-chamber capture detection may be implemented using detection windows having dimensions of time and amplitude. The detection windows are associated with expected features, such as expected signal peaks, under a particular capture condition. The cardiac electrogram signal features are compared to detection windows to determine the capture condition.

Claims

1. A method of operating a cardiac rhythm management device in a patient to classify a cardiac response to multi-chamber pacing, comprising:

delivering a first pacing pulse to a left heart chamber during a cardiac cycle;

delivering a second pacing pulse to a right heart chamber during the cardiac cycle;

sensing a cardiac electrogram signal following the first and second pacing pulses;

determining at least whether (a) a first signal feature of the cardiac signal is disposed within a first detection window, and (b) a second signal feature of the cardiac signal is disposed within a second detection window, at least one of the first and second detection windows being finitely bounded in both time and amplitude; and

classifying the cardiac response to the first and second pacing pulses as one of bi-chamber capture and a single chamber capture based on the determination of (a) and (b).

2. The method of claim 1, wherein the first signal feature comprises a first peak and the second signal feature comprises a second peak of the cardiac signal.

3. The method of claim 1, wherein both the first and second detection windows are finitely bounded in both time and amplitude.

4. The method of claim 3, wherein the first detection window covers a first amplitude range and the second detection window covers a second amplitude range opposite in polarity to the first amplitude range.

5. The method of claim 3, wherein the first detection window covers a first amplitude range and the second detection window covers a second amplitude range of the same polarity as the first amplitude range.

6. The method of claim 1, wherein the single chamber capture refers to capture of a specific one of the left and right heart chambers.

7. The method of claim 1, wherein the first and second detection windows are non-overlapping.

8. The method of claim 1, wherein the first detection window is associated with bi-chamber capture and the second detection window is associated with a specific single chamber capture.

9. The method of claim 1, wherein the first and second detection windows are both associated with bi-chamber capture.

10. The method of claim 1, wherein the determining step also determines whether (c) a third signal feature of the cardiac signal is disposed within a third detection window, and the classifying step is based also on the determination of (c).

11. The method of claim 1, wherein the first and second pacing pulses are delivered substantially simultaneously.

12. The method of claim 1, wherein the left heart chamber is a left ventricle and the right heart chamber is a right ventricle.

13. An implantable system for classifying a cardiac response to multi-chamber pacing pulses, comprising:

a pulse delivery system configured to deliver a first pacing pulse to a left heart chamber during a cardiac cycle and a second pacing pulse to a right heart chamber during the cardiac cycle;

a sensor system configured to sense a cardiac electrogram signal following the first and second pacing pulses; and

a processor coupled to the sensor system, the processor configured to determine whether (a) a first signal feature of the cardiac signal is disposed within a first detection window, and (b) a second signal feature of the cardiac signal is disposed within a second detection window, the processor further being configured to classify the cardiac response to the first and second pacing pulses as one of bi-chamber capture and a single chamber capture based on the determination of (a) and (b);

wherein at least one of the first and second detection windows is finitely bounded in both time and amplitude.

14. The system of claim 13, wherein the first signal feature comprises a first peak and the second signal feature comprises a second peak of the cardiac signal.

15. The system of claim 13, wherein both the first and second detection windows are finitely bounded in both time and amplitude.

16. The system of claim 15, wherein the first detection window covers a first amplitude range and the second detection window covers a second amplitude range opposite in polarity to the first amplitude range.

17. The system of claim 15, wherein the first detection window covers a first amplitude range and the second detection window covers a second amplitude range of the same polarity as the first amplitude range.

18. The system of claim 13, wherein the single chamber capture refers to capture of a specific one of the left and right heart chambers.

19. The system of claim 13, wherein the first and second detection windows are non-overlapping.

20. The system of claim 13, wherein the first detection window is associated with bi-chamber capture and the second detection window is associated with a specific single chamber capture.

21. The system of claim 13, wherein the first and second detection windows are both associated with bi-chamber capture.

22. The system of claim 13, wherein the processor is also configured to determine whether (c) a third signal feature of the cardiac signal is disposed within a third detection window, and the processor is configured to classify the cardiac response based on the determination of (a), (b), and (c).

23. The system of claim 13, wherein the pulse delivery system is configured to deliver the first and second pacing pulses substantially simultaneously.

24. The system of claim 13, wherein the left heart chamber is a left ventricle and the right heart chamber is a right ventricle.