Method and system for ventricular fusion prevention

• US 6,654,637 B2
• Filed: 04/30/2001
• Issued: 11/25/2003
• Est. Priority Date: 04/30/2001
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Wohlgemuth, Peter, Rouw, Mattias
• Primary Examiner(s): EVANISKO, GEORGE ROBERT
• Application Number:
  US09/844,070
• Publication Number:
  US 20020183795A1
• Time in Patent Office: 939 Days
• Field of Search: 607/9, 607/11, 607/27, 607/28
• US Class Current: 607/7
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence
• CPC Class Codes: A61N 1/3682 with a variable atrioventricular delay

Abstract

A method and system for ventricular fusion prevention is provided. It is determined whether an atrial sense occurred within a prior wait time and a scheduled ventricular pace is administered if no atrial sense occurred. If an atrial sense occurred and a ventricular sense follows within an additional wait time, the scheduled ventricular pace is canceled to avoid a fusion beat. If an atrial sense occurred and no ventricular sense follows within an additional wait time, the scheduled ventricular pace is administered. In another embodiment, the max AV interval is increased if too many scheduled ventricular paces are canceled to avoid fusion beats.

Claims

1. A method for ventricular fusion prevention, comprising:

providing a value for wait time,

scheduling a ventricular pace;

determining whether an atrial sense occurred within the wait time;

administering the scheduled ventricular pace if no atrial sense occurred within the wait time;

awaiting either a ventricular sense or an additional wait time, if an atrial sense occurred within the wait time;

canceling the ventricular pace if the ventricular sense occurs; and

administering the scheduled ventricular pace if the additional wait time passes.

2. The method of claim 1, wherein an individual patient determines the wait time by testing.

3. The method of claim 1, wherein the wait time is in the range of 0 to 30 ms.

4. The method of claim 1, wherein the wait time is selected from the ranges consisting of 10 ms to 30 ms, 20 ms to 30 ms, and 23 ms to 27 ms.

5. The method of claim 1, wherein the wait time is 25 ms.

6. The method of claim 1, further comprising:

providing a max AV interval;

incrementing a fusion beat counter if the ventricular pace is canceled; and

increasing the max AV interval if the fusion beat counter exceeds a predetermined value.

7. The method of claim 6, wherein an individual patient determines the value of the fusion beat counter by testing.

8. The method of claim 6, wherein the value of the fusion beat counter is from 1 to 20.

9. The method of claim 6, wherein the fusion beat counter value is selected from the ranges consisting of 1 to 20, 1 to 10, and 1 to 5.

10. The method of claim 6, wherein the value of the fusion beat counter is 3.

11. The method of claim 6, wherein the physician for an individual patient determines the value of the max AV interval increase.

12. The method of claim 6, wherein the value of the max AV interval is increased by 50 ms.

13. The method of claim 6, wherein the physician for an individual patient determines an amount to increase the value of the max AV interval.

14. The method of claim 6, wherein the value of the max AV interval is increased to 220 ms.

15. An implantable medical system with ventricular fusion prevention, comprising:

means for providing a value for wait time,

means for scheduling a ventricular pace;

means for determining whether an atrial sense occurred within the wait time;

means for administering the scheduled ventricular pace if no atrial sense occurred within the wait time;

means for awaiting either a ventricular sense or an additional wait time, if an atrial sense occurred within the wait time;

means for canceling the ventricular pace if the ventricular sense occurs; and

means for administering the scheduled ventricular pace if the additional wait time passes.

16. The system of claim 15, wherein the wait time is in the range of 0 to 30 ms.

17. The method of claim 15, wherein the wait time is selected from the ranges consisting of 10 ms to 30 ms, 20 ms to 30 ms, and 23 ms to 27 ms.

18. The method of claim 15, wherein the wait time is 25 ms.

19. The system of claim 15, further comprising:

means for providing a max AV interval;

means for incrementing a fusion beat counter if the ventricular pace is canceled; and

means for increasing the max AV interval if the fusion beat counter exceeds a predetermined value.

20. The system of claim 19, wherein the value of the fusion beat counter is from 1 to 20.

21. The method of claim 19, wherein the value of the fusion beat counter is selected from the ranges consisting of 1 to 20, 1 to 10, and 1 to 5.

22. The system of claim 19, wherein the value of the fusion beat counter is 3.

23. The system of claim 19, wherein the value of the max AV interval is increased by 50 ms.

24. The system of claim 19, wherein the value of the max AV interval is increased to 220 ms.

25. A computer usable medium storing computer readable program code having a program for ventricular fusion prevention, comprising:

computer readable program code that provides a value for wait time,

computer readable program code that schedules a ventricular pace;

computer readable program code that determines whether an atrial sense occurred within the wait time;

computer readable program code that administers the scheduled ventricular pace if no atrial sense occurred within the wait time;

computer readable program code that awaits either a ventricular sense or an additional wait time, if an atrial sense occurred within the wait time;

computer readable program code that cancels the ventricular pace if the ventricular sense occurs; and

computer readable program code that administers the scheduled ventricular pace if the additional wait time passes.

26. The program of claim 25, wherein the wait time is in the range of 0 to 30 ms.

27. The method of claim 25, wherein the wait time is selected from the ranges consisting of 10 ms to 30 ms, 20 ms to 30 ms, and 23 ms to 27 ms.

28. The method of claim 25, wherein the wait time is 25 ms.

29. The program of claim 25, further comprising:

computer readable program code that provides a max AV interval;

computer readable program code that increments a fusion beat counter if the ventricular pace is canceled; and

computer readable program code that increases the max AV interval if the fusion beat counter exceeds a predetermined value.

30. The program of claim 29, wherein the value of the fusion beat counter is from 1 to 20.

31. The method of claim 29, wherein the value of the fusion beat counter is selected from the ranges consisting of 1 to 20, 1 to 10, and 1 to 5.

32. The program of claim 29, wherein the value of the fusion beat counter is 3.

33. The program of claim 29, wherein the value of the max AV interval is increased by 50 ms.

34. The program of claim 29, wherein the value of the max AV interval is increased to 220 ms.