Cardiac rhythm pacing rate selection for automatic capture threshold testing

• US 7,761,159 B2
• Filed: 03/16/2005
• Issued: 07/20/2010
• Est. Priority Date: 03/17/2005
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Foster, Clayton Scott, Yost, David William
• Primary Examiner(s): BOCKELMAN, MARK
• Application Number:
  US11/083,127
• Publication Number:
  US 20060212084A1
• Time in Patent Office: 1,952 Days
• Field of Search: 607/9, 607 17- 20, 607 21- 26, 607/28
• US Class Current: 607/19
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371
• CPC Class Codes: A61N 1/3712 Auto-capture, i.e. automatic adjustment of the stimulation threshold

Abstract

Cardiac devices and methods that select pacing rates for automatic threshold tests based on a patient'"'"'s hemodynamic need. A sensor-indicated pacing rate corresponding to a patient'"'"'s hemodynamic need is determined. A test pacing rate is selected from either the sensor-indicated rate or another rate. Capture threshold testing is performed using the selected pacing rate.

Claims

1. A method for performing a capture threshold test with a cardiac pacing device adapted to provide pacing therapy to a heart of a patient, the method comprising:

providing a non-sensor-indicated pacing rate to the pacing device

operating the pacing device in a current pacing mode before the capture threshold test;

determining a sensor-indicated pacing rate corresponding to the patient'"'"'s sensed hemodynamic need;

selecting either the sensor-indicated pacing rate or the non-sensor-indicated pacing rate as a test pacing rate;

switching operation of the pacing device from the current pacing mode to the capture threshold test; and

performing the capture threshold test using the test pacing rate.

2. The method of claim 1, wherein selecting the test pacing rate comprises:

selecting the sensor-indicated pacing rate if the sensor-indicated pacing rate is greater than the non-sensor-indicated pacing rate; and

selecting the non-sensor-indicated pacing rate if the non-sensor-indicated pacing rate is greater than the sensor-indicated pacing rate.

3. The method of claim 1, wherein selecting the test pacing rate comprises selecting one of the sensor-indicated pacing rate and a predetermined pacing rate.

4. The method of claim 1, wherein selecting the test pacing rate comprises selecting one of the sensor-indicated pacing rate and a pacing rate determined based on a heart rate before the capture threshold test.

5. The method of claim 1, wherein selecting the test pacing rate comprises:

selecting one of the sensor-indicated pacing rate and a predetermined pacing rate if a current pacing mode comprises a tracking mode; and

selecting one of the sensor-indicated pacing rate and a pacing rate determined based on a heart rate before the capture threshold test if the current pacing mode comprises a non-tracking mode.

6. The method of claim 5, wherein selecting one of the sensor-indicated pacing rate and the predetermined pacing rate comprises using a shortened AV-delay if the current pacing mode comprises a tracking mode.

7. The method of claim 1, wherein selecting the test pacing rate comprises selecting the test pacing rate to reduce fusion beats during the capture threshold test.

8. The method of claim 1, wherein selecting the test pacing rate comprises selecting the test pacing rate to increase a likelihood of captured beats during the capture threshold test.

9. The method of claim 1, wherein the current pacing mode is a rate-adaptive mode, and wherein selecting the test pacing rate comprises selecting the test pacing rate to reduce a pacing rate change when switching from the current pacing mode to the capture threshold test.

10. The method of claim 1, further comprising:

after the capture threshold test, switching operation of the pacing device from the capture threshold test to a subsequent pacing mode that is a rate-adaptive mode;

wherein selecting the test pacing rate comprises selecting the test pacing rate to reduce a pacing rate change when switching from the capture threshold test to the subsequent pacing mode.

11. The method of claim 1, wherein performing the capture threshold test using the test pacing rate comprises adapting the test pacing rate to meet the patient'"'"'s hemodynamic need.

12. The method of claim 1, wherein performing the capture threshold test using the test pacing rate comprises:

delivering pacing pulses at the test pacing rate;

sensing cardiac signals respectively following the pacing pulses; and

determining a capture threshold based on the sensed cardiac signals.

13. The method of claim 1, wherein the non-sensor-indicated pacing rate comprises a lower rate limit.

14. The method of claim 1, wherein the non-sensor-indicated pacing rate comprises a pseudo lower rate limit.

15. The method of claim 1, wherein the non-sensor-indicated pacing rate is based on a measured heart rate.

16. The method of claim 1, wherein the non-sensor-indicated pacing rate comprises a programmable pacing rate.

17. The method of claim 1, wherein the non-sensor-indicated pacing rate comprises a measured heart rate added to a predetermined offset.

18. The method of claim 17, wherein the measured heart rate is determined prior to the capture threshold test based on a predetermined number of sensed and paced beats.

19. The method of claim 1, wherein determining the sensor-indicated pacing rate corresponding to the patient'"'"'s sensed hemodynamic need comprises determining the sensor-indicated pacing rate based on patient activity.

20. The method of claim 1, wherein determining the sensor-indicated pacing rate corresponding to the patient'"'"'s sensed hemodynamic need comprises determining the sensor-indicated pacing rate based on patient respiration.

21. The method of claim 1, wherein the selecting is based on whether the current pacing mode is a tracking mode or a non-tracking mode.