Adaptive safety pacing

• US 20050137640A1
• Filed: 09/28/2004
• Published: 06/23/2005
• Est. Priority Date: 12/08/2003
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Zhu, Qingsheng, Freeberg, Scott M., Lyden, Michael J.
• Granted Patent: US 7,813,799 B2
• Time in Patent Office: Days
• US Class Current: 607/28
• CPC Class Codes: A61N 1/3712 Auto-capture, i.e. automatic adjustment of the stimulation threshold

Abstract

Methods and systems involve adjusting an energy used for safety pacing based on the capture threshold. The safety pacing energy may be adjusted prior to a capture threshold test. During the capture threshold test, backup safety paces are delivered using the adjusted pacing energy. Following suspension of automatic capture verification, the device may enter a suspension mode. During the suspension mode, safety pacing pulses are delivered using a pacing energy adjusted based on capture threshold.

Claims

1. A method of delivering cardiac safety pacing to a patient, comprising:

determining a capture threshold; and

adjusting an energy for safety pacing based on the capture threshold.

2. The method of claim 1, wherein:

determining the capture threshold comprises determining the capture threshold of a first heart chamber; and

adjusting the energy for safety pacing comprises adjusting the energy for safety pacing in a second heart chamber based on the capture threshold of the first heart chamber.

3. The method of claim 1, determining the capture threshold comprises:

performing an automatic capture threshold test; and

acquiring the capture threshold during the automatic capture threshold test.

4. The method of claim 1, further comprising:

performing a capture threshold test; and

delivering safety pacing pulses during the capture threshold test using the adjusted energy.

5. The method of claim 1, further comprising:

initiating a capture threshold test;

determining if automatic capture verification is active;

adjusting the energy for safety pacing to a predetermined amount above a capture threshold if automatic capture verification is active; and

delivering safety pacing pulses using the adjusted safety pacing energy during the capture threshold test.

6. The method of claim 1, further comprising:

initiating a capture threshold test;

determining if automatic capture verification is suspended;

adjusting the energy for safety pacing based on the pacing energy used while the automatic capture verification is suspended; and

delivering safety pacing pulses using the adjusted safety pacing energy during the capture threshold test.

7. The method of claim 1, further comprising:

suspending automatic capture verification; and

delivering safety pacing pulses using the adjusted safety pacing energy during automatic capture verification suspension.

8. The method of claim 1, further comprising:

suspending automatic capture verification; and

adjusting the energy for safety pacing during automatic capture verification suspension to a predetermined amount above the capture threshold.

9. The method of claim 1, wherein adjusting the energy for safety pacing comprises adjusting the energy for safety pacing to a default value if the adjusted safety pacing energy is below a threshold.

10. A medical device for delivering cardiac pacing therapy to a patient comprising:

a plurality of electrodes configured to electrically couple to a heart and to deliver pacing pulses to a heart;

capture threshold detection circuitry coupled to the electrodes and configured to determine a capture threshold energy associated with the pacing pulses; and

a pulse generator coupled to the plurality of electrodes and the capture threshold detection circuitry, the pulse generator configured to adjust an energy for safety pacing based on the capture threshold energy.

11. The system of claim 10, wherein the plurality of electrodes comprises one or more endocardial electrodes.

12. The system of claim 10, wherein the plurality of electrodes comprises one or more epicardial electrodes.

13. The system of claim 10, wherein the capture threshold detection circuitry is configured to perform an automatic capture threshold test and to determine the capture threshold during the automatic capture threshold test.

14. The system of claim 10, wherein:

the capture threshold detection circuitry is configured to perform a capture threshold test; and

the pulse generator is configured to deliver safety pacing pulses during the capture threshold test using the adjusted energy.

15. The system of claim 10, wherein:

the capture threshold detection circuitry is configured to initiate a capture threshold test; and

the pulse generator is configured to determine if the automatic capture verification is active, adjust the energy for safety pacing to a predetermined amount above the capture threshold if automatic capture verification is active, and deliver safety pacing pulses using the adjusted safety pacing energy during the capture threshold test.

16. The system of claim 10, wherein:

the capture threshold detection circuitry is configured to initiate a capture threshold test; and

the pulse generator is configured to determine if automatic capture verification is suspended, adjust the energy for safety pacing based on the pacing energy used while the automatic capture verification is suspended and deliver safety pacing pulses using the adjusted safety pacing energy during the capture threshold test.

17. The system of claim 10, wherein the pulse generator is configured to suspend automatic capture verification and deliver safety pacing pulses using the adjusted safety pacing energy during automatic capture verification suspension.

18. The system of claim 10, wherein the pulse generator is configured to suspend automatic capture verification and adjust the energy for safety pacing during automatic capture verification suspension to a predetermined amount above the capture threshold.

19. The system of claim 10, wherein the pulse generator is configured to adjust the energy for safety pacing to a default value if the adjusted safety pacing energy is below a threshold.

20. A system for adjusting safety pacing energy, comprising:

means for determining a capture threshold;

means for adjusting an energy for safety pacing based on the capture threshold.

21. The system of claim 20, further comprising:

means for determining the capture threshold of a first heart chamber; and

means for adjusting the energy for safety pacing of a second heart chamber based on the capture threshold determined for the first heart chamber.

22. The system of claim 20, further comprising:

means for initiating a capture threshold test;

means for determining if automatic capture verification is active;

means for adjusting the energy for safety pacing to a predetermined amount above a capture threshold if automatic capture verification is active; and

means for delivering safety pacing pulses using the adjusted safety pacing energy during the capture threshold test.

23. The system of claim 20, further comprising:

means for initiating a capture threshold test;

means for determining if automatic capture verification is suspended;

means for adjusting the energy for safety pacing based on the pacing energy used while the automatic capture verification is suspended; and

means for delivering safety pacing pulses using the adjusted safety pacing energy during the capture threshold test.

24. The system of claim 20, further comprising:

means for suspending automatic capture verification; and

means for delivering safety pacing pulses using the adjusted safety pacing energy during automatic capture verification suspension.

25. The system of claim 20, further comprising:

means for suspending automatic capture verification; and

means for adjusting the energy for safety pacing during automatic capture verification suspension to a predetermined amount above the capture threshold.