Pacing therapy for extending atrial refractory period

• US 20040102811A1
• Filed: 11/22/2002
• Published: 05/27/2004
• Est. Priority Date: 11/22/2002
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Schwartz, Mark, Sra, Jasbir
• Granted Patent: US 7,203,538 B2
• Time in Patent Office: Days
• US Class Current: 607/5
• CPC Class Codes: A61N 1/3622 comprising two or more electrodes co-operating with different heart regions
• CPC Class Codes: A61N 1/395 for treating atrial fibrillation
• CPC Class Codes: A61N 1/39622 Pacing therapy

Abstract

A device and method are presented for prolonging the atrial effective refractory period with pacing therapy. Such refractory period prolongation renders the atrial tissue less susceptible to the onset of atrial fibrillation. A particularly useful application is during the period after application of electrical therapy to the atria.to terminate an episode of atrial fibrillation.

Claims

1. A cardiac rhythm management device, comprising:

an atrial sensing channel for sensing atrial electrical activity;

an atrial pacing channel for delivering atrial pacing pulses;

a shock pulse generator for delivering atrial defibrillation shocks;

a controller programmed with executable instructions for performing functions which include;

detecting atrial fibrillation;

delivering an atrial defibrillation shock after atrial fibrillation is detected;

delivering atrial pacing pulses in accordance with a pacing mode for a specified period of time following an atrial defibrillation shock; and

,

delivering one or more non-excitatory stimulation pulses to an atrium during an atrial refractory period after an atrial pacing pulse.

2. The device of claim 1 wherein the non-excitatory stimulation pulses are of lesser amplitude than the atrial pacing pulses.

3. The device of claim 1 wherein the non-excitatory stimulation pulses are of equal or greater amplitude than the atrial pacing pulses.

4. The device of claim 1 wherein the non-excitatory stimulation pulses are delivered through the atrial pacing channel.

5. The device of claim 1 further comprising an atrial stimulation channel for delivering the non-excitatory stimulation pulses.

6. The device of claim 1 further comprising a plurality of atrial stimulation channels and wherein the controller is programmed to deliver non-excitatory atrial stimulation pulses through the plurality of atrial stimulation channels after an atrial pace during the specified period of time.

7. The device of claim 1 wherein the controller is programmed to deliver atrial pacing pulses in an overdrive pacing mode for the specified period of time following delivery of an atrial defibrillation shock.

8. The device of claim 1 further comprising a ventricular sensing channel for sensing ventricular electrical activity and wherein the controller is programmed to deliver the atrial defibrillation shock in synchrony with an R wave.

9. A method for treating atrial fibrillation, comprising:

sensing atrial electrical activity in order to detect atrial fibrillation;

delivering an atrial defibrillation shock upon detection of atrial fibrillation;

delivering atrial pacing pulses to an atrial pacing site in accordance with a pacing mode for a specified period of time following an atrial defibrillation shock; and

,

delivering one or more non-excitatory stimulation pulses to an atrial stimulation site during the atrial refractory period after an atrial pacing pulse.

10. The method of claim 9 wherein the non-excitatory stimulation pulses are of lesser amplitude than the atrial pacing pulses.

11. The method of claim 9 wherein the non-excitatory stimulation pulses are of equal or greater amplitude than the atrial pacing pulses.

12. The method of claim 9 further comprising delivering the non-excitatory stimulation pulses to an atrial stimulation site different from the atrial pacing site.

13. The method of claim 9 wherein the atrial pacing site is in one atrium and the atrial stimulation site is in the contralateral atrium.

14. The method of claim 9 further comprising delivering non-excitatory atrial stimulation pulses to a plurality of atrial stimulation sites after an atrial pace during the specified period of time.

15. The method of claim 9 further comprising delivering atrial paces in an overdrive pacing mode for the specified period of time following delivery of an atrial defibrillation shock.

16. A cardiac rhythm management device, comprising:

an atrial sensing channel for sensing atrial electrical activity;

a first atrial pacing channel for delivering pacing pulses to an atrium;

a controller programmed with executable instructions for performing functions which include;

detecting atrial fibrillation;

delivering atrial anti-tachycardia pacing after detection of atrial fibrillation;

delivering atrial pacing pulses in accordance with a bradycardia pacing mode for a specified period of time following the atrial anti-tachycardia pacing; and

,

delivering one or more non-excitatory atrial stimulation pulses during the atrial refractory period after an atrial pacing pulse while pacing with the bradycardia pacing mode.

17. The device of claim 16 wherein the non-excitatory stimulation pulses are of lesser amplitude than the atrial pacing pulses.

18. The device of claim 16 further comprising a second atrial pacing channel for delivering the non-excitatory stimulation pulses.

19. The device of claim 16 wherein the controller is programmed to deliver atrial pacing pulses in an overdrive pacing mode for the specified period of time following delivery of the atrial anti-tachycardia pacing.

20. The device of claim 16 further comprising a plurality of atrial stimulation channels and wherein the controller is programmed to deliver non-excitatory atrial stimulation pulses through the plurality of atrial stimulation channels after an atrial pace during the specified period of time.

21. A method for treating atrial fibrillation, comprising:

sensing atrial electrical activity in order to detect atrial fibrillation;

delivering atrial anti-tachycardia pacing upon detection of atrial fibrillation;

delivering atrial pacing pulses to an atrial pacing site in accordance with a bradycardia pacing mode for a specified period of time following the anti-tachycardia pacing; and

,

delivering one or more non-excitatory stimulation pulses to an atrium during the atrial refractory period after an atrial pacing pulse while pacing in the bradycardia pacing mode.

22. The method of claim 21 wherein the non-excitatory stimulation pulses are of lesser amplitude than the atrial pacing pulses.

23. The method of claim 21 further comprising delivering the non-excitatory stimulation pulses to an atrial stimulation site different from the atrial pacing site.

24. The method of claim 21 wherein the atrial pacing site is in one atrium and the atrial stimulation site is in the contralateral atrium.

25. The method of claim 21 further comprising delivering non-excitatory atrial stimulation pulses to a plurality of atrial stimulation sites after an atrial pace during the specified period of time.

26. The method of claim 21 further comprising delivering pacing pulses to the atria in an overdrive pacing mode for the specified period of time following delivery of the atrial anti-tachycardia pacing.

27. A cardiac rhythm management device, comprising:

means for sensing atrial electrical activity in order to detect atrial fibrillation;

means for delivering an atrial defibrillation shock upon detection of atrial fibrillation;

means for delivering atrial pacing pulses to an atrial pacing site in accordance with a pacing mode for a specified period of time following an atrial defibrillation shock; and

,

means for delivering one or more non-excitatory stimulation pulses to an atrial stimulation site during the atrial refractory period after each atrial pacing pulse during the specified period of time.

28. The device of claim 27 wherein the non-excitatory stimulation pulses are of lesser amplitude than the atrial pacing pulses.

29. The device of claim 27 wherein the non-excitatory stimulation pulses are of equal or greater amplitude than the atrial pacing pulses.

30. The device of claim 27 further comprising means for delivering the non-excitatory stimulation pulses to an atrial stimulation site different from the atrial pacing site.

31. The device of claim 27 wherein the atrial pacing site is in one atrium and the atrial stimulation site is in the contralateral atrium.

32. The device of claim 27 further comprising means for delivering non-excitatory atrial stimulation pulses to a plurality of atrial stimulation sites after an atrial pace during the specified period of time.

33. The device of claim 27 further comprising means for delivering atrial paces in an overdrive pacing mode for the specified period of time following delivery of an atrial defibrillation shock.

34. A cardiac rhythm management device, comprising:

means for sensing atrial electrical activity in order to detect atrial fibrillation;

means for delivering atrial anti-tachycardia pacing upon detection of atrial fibrillation;

means for delivering atrial pacing pulses to an atrial pacing site in accordance with a bradycardia pacing mode for a specified period of time following the antitachycardia pacing; and

,

means for delivering one or more non-excitatory stimulation pulses to an atrium during the atrial refractory period after each atrial pacing pulse during the specified period of time.

35. The device of claim 34 wherein the non-excitatory stimulation pulses are of lesser amplitude than the atrial pacing pulses.

36. The device of claim 34 further comprising means for delivering the non-excitatory stimulation pulses to an atrial stimulation site different from the atrial pacing site.

37. The device of claim 34 wherein the atrial pacing site is in one atrium and the atrial stimulation site is in the contralateral atrium.

38. The device of claim 34 further comprising means for delivering non-excitatory atrial stimulation pulses to a plurality of atrial stimulation sites after an atrial pace during the specified period of time.

39. The device of claim 34 further comprising means for delivering pacing pulses to the atria in an overdrive pacing mode for the specified period of time following delivery of the atrial anti-tachycardia pacing.