Selective nerve fiber stimulation for treating heart conditions

• US 20050187586A1
• Filed: 02/24/2005
• Published: 08/25/2005
• Est. Priority Date: 08/31/2001
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: BioControl Medical (B.C.M) Ltd.
• Inventors: David, Tamir B., Cohen, Ehud, Ayal, Shai
• Granted Patent: US 8,386,056 B2
• Time in Patent Office: Days
• US Class Current: 607/9
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/4029 for evaluating the peripheral nervous systems A61B5/24 takes precedence
• CPC Class Codes: A61B 5/4041 Evaluating nerves condition
• CPC Class Codes: A61B 5/412 Detecting or monitoring sepsis
• CPC Class Codes: A61B 5/7217 of noise originating from a therapeutic or surgical apparatus, e.g. from a pacemaker
• CPC Class Codes: A61N 1/0551 Spinal or peripheral nerve electrodes
• CPC Class Codes: A61N 1/0556 Cuff electrodes
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/3621 for treating or preventing abnormally high heart rate
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy

Abstract

Apparatus is provided that includes an electrode device, adapted to be coupled to a vagus nerve of a subject, and a control unit, adapted to drive the electrode device to apply to the vagus nerve a current that reduces heart rate variability of the subject. Also provided is a method comprising applying to a vagus nerve of a subject a current that reduces heart rate variability of the subject.

Claims

1. A method for treating a subject, comprising:

applying, to a site of the subject, a current in respective pulse bursts in each of a plurality of cardiac cycles of the subject, the site selected from;

a vagus nerve and an epicardial fat pad;

synchronizing the bursts with the cardiac cycles; and

configuring the current so as to treat a condition of the subject selected from;

atrial arrhythmia, and atrial arrhythmia combined with heart failure.

2. The method according to claim 1, comprising driving an implantable cardioverter defibrillator (ICD) to apply energy to a heart of the subject, the ICD being in communication with a control unit that drives the application of the current.

3. The method according to claim 1, wherein applying the current comprises applying the current using parameters that only vary responsively to a configuration command.

4. The method according to claim 1, wherein applying the current comprises applying the current using parameters that do not vary responsively to feedback.

5. The method according to claim 4, wherein applying the current comprises applying the current responsively to determining that a heart rate of the subject is greater than a threshold value.

6. The method according to claim 5, wherein applying the current comprises setting the threshold value to be greater than a normal heart rate.

7. The method according to claim 5, wherein applying the current comprises applying the current continuously.

8. The method according to claim 4, wherein applying the current comprises cycling between “

on”

periods, during which the current is applied, and “

off”

periods, during which the current is withheld.

9. The method according to claim 8, wherein applying the current comprises applying the current responsively to determining that a heart rate of the subject is greater than a threshold value that is greater than a normal heart rate.

10. The method according to claim 4, wherein applying the current comprises applying the current continuously.

11. The method according to claim 10, wherein applying the current comprises applying the current responsively to determining that a heart rate of the subject is greater than a threshold value that is greater than a normal heart rate.

12. The method according to claim 1, wherein applying the current comprises:

cycling between “

on”

periods, during which the current is applied, and “

off”

periods, during which the current is withheld; and

applying the current responsively to determining that a heart rate of the subject is greater than a threshold value.

13. The method according to claim 12, wherein applying the current comprises setting the threshold value to be greater than a normal heart rate.

14. The method according to claim 12, wherein applying the current comprises applying the current using parameters that do not vary responsively to feedback.

15. The method according to claim 1, wherein applying the current comprises:

applying the current continuously; and

applying the current responsively to determining that a heart rate of the subject is greater than a threshold value.

16. The method according to claim 15, wherein applying the current comprises setting the threshold value to be greater than a normal heart rate.

17. The method according to claim 1, wherein applying the current comprises setting a control parameter of a feedback algorithm governing the current application to be a number of pulses per each one of the bursts.

18. The method according to claim 17, wherein the feedback algorithm includes an integral feedback algorithm that has inputs including a detected heart rate of the subject and a target heart rate of the subject.

19. The method according to claim 17, wherein applying the current comprises cycling between “

on”

periods, during which the current is applied, and “

off”

periods, during which the current is withheld.

20. The method according to claim 19, wherein applying the current comprises applying the current using an integral feedback algorithm that has inputs including a detected heart rate of the subject and a target heart rate of the subject.

21. The method according to claim 17, wherein applying the current comprises applying the current continuously.

22. The method according to claim 21, wherein applying the current comprises applying the current using an integral feedback algorithm that has inputs including a detected heart rate of the subject and a target heart rate of the subject.

23. The method according to claim 1, wherein applying the current comprises applying the current responsively to determining that a heart rate of the subject is greater than a threshold value.

24. The method according to claim 23, wherein applying the current comprises setting the threshold value to be greater than a normal heart rate.

25. The method according to claim 1, wherein applying the current comprises applying the current to the vagus nerve, and configuring the current so as to stimulate only medium-diameter fibers of the vagus nerve.

26. The method according to claim 25, wherein applying the current comprises:

applying a stimulating current, which is capable of inducing action potentials in large- and medium-diameter fibers of the vagus nerve, but not in small-diameter fibers of the vagus nerve; and

applying an inhibiting current, which is capable of inhibiting the action potentials induced in the large-diameter fibers by the stimulating current.

27. A method for treating a subject, comprising:

applying, to a site of the subject, a current using parameters that do not vary responsively to feedback, the site selected from;

a vagus nerve and an epicardial fat pad; and

configuring the current so as to treat a condition of the subject selected from;

atrial arrhythmia, and atrial arrhythmia combined with heart failure.

28. The method according to claim 27, wherein applying the current comprises setting the parameters only responsively to a configuration command.

29. The method according to claim 27, wherein applying the current comprises cycling between “

on”

periods, during which the current is applied, and “

off”

periods, during which the current is withheld.

30. The method according to claim 27, wherein applying the current comprises applying the current continuously.

31. The method according to claim 27, wherein applying the current comprises applying the current responsively to determining that a heart rate of the subject is greater than a threshold value.

32. The method according to claim 31, wherein applying the current comprises setting the threshold value to be greater than a normal heart rate.

33. The method according to claim 27, wherein applying the current comprises applying the current to the vagus nerve, and configuring the current so as to stimulate only medium-diameter fibers of the vagus nerve.

34. The method according to claim 33, wherein applying the current comprises:

applying a stimulating current, which is capable of inducing action potentials in large- and medium-diameter fibers of the vagus nerve, but not in small-diameter fibers of the vagus nerve; and

applying an inhibiting current, which is capable of inhibiting the action potentials induced in the large-diameter fibers by the stimulating current.

35. A method for treating a subject, comprising:

applying a current in pulse bursts to a site of the subject selected from;

a vagus nerve and an epicardial fat pad;

setting a control parameter of a feedback algorithm governing the current application to be a number of pulses per each of the bursts; and

configuring the current so as to treat a condition of the subject selected from;

atrial arrhythmia, and atrial arrhythmia combined with heart failure.

36. The method according to claim 35, wherein applying the current comprises cycling between “

on”

periods, during which the current is applied, and “

off”

periods, during which the current is withheld.

37. The method according to claim 36, wherein the feedback algorithm includes an integral feedback algorithm that has inputs including a detected heart rate of the subject and a target heart rate of the subject.

38. The method according to claim 35, wherein applying the current comprises applying the current continuously.

39. The method according to claim 35, wherein applying the current comprises applying the current using an integral feedback algorithm that has inputs including a detected heart rate of the subject and a target heart rate of the subject.

40. The method according to claim 35, wherein applying the current comprises applying the current to the vagus nerve, and configuring the current so as to stimulate only medium-diameter fibers of the vagus nerve.

41. The method according to claim 40, wherein applying the current comprises:

applying a stimulating current, which is capable of inducing action potentials in large- and medium-diameter fibers of the vagus nerve, but not in small-diameter fibers of the vagus nerve; and

applying an inhibiting current, which is capable of inhibiting the action potentials induced in the large-diameter fibers by the stimulating current.

42. A method for treating a subject, comprising:

determining that a heart rate of the subject is greater than a threshold value;

responsively to the determination, applying a current to a site of the subject selected from;

a vagus nerve and an epicardial fat pad; and

configuring the current so as to treat a condition of the subject selected from;

atrial arrhythmia, and atrial arrhythmia combined with heart failure.

43. The method according to claim 42, wherein applying the current comprises applying the current to the vagus nerve, and configuring the current so as to stimulate only medium-diameter fibers of the vagus nerve.

44. The method according to claim 43, wherein applying the current comprises:

applying a stimulating current, which is capable of inducing action potentials in large- and medium-diameter fibers of the vagus nerve, but not in small-diameter fibers of the vagus nerve; and

applying an inhibiting current, which is capable of inhibiting the action potentials induced in the large-diameter fibers by the stimulating current.

45. A method for treating a subject, comprising:

applying a current to a vagus nerve of the subject;

configuring the current so as to stimulate only medium-diameter fibers of the vagus nerve; and

configuring the current so as to treat a condition of the subject selected from;

atrial arrhythmia, and atrial arrhythmia combined with heart failure.

46. The method according to claim 45, wherein applying the current comprises:

applying a stimulating current, which is capable of inducing action potentials in large- and medium-diameter fibers of the vagus nerve, but not in small-diameter fibers of the vagus nerve; and

applying an inhibiting current, which is capable of inhibiting the action potentials induced in the large-diameter fibers by the stimulating current.

47. The method according to claim 45, comprising driving an implantable cardioverter defibrillator (ICD) to apply energy to a heart of the subject, the ICD being in communication with a control unit that drives the application of the current.

48. The method according to claim 45, wherein applying the current comprises applying the current responsively to determining that a heart rate of the subject is greater than a threshold value that is greater than a normal heart rate.

49. A method for treating a subject, comprising:

applying a current to a site of the subject selected from;

a vagus nerve and an epicardial fat pad;

configuring the current so as to treat a condition of the subject selected from;

atrial arrhythmia, and atrial arrhythmia combined with heart failure; and

driving an implantable cardioverter defibrillator (ICD) to apply energy to a heart of the subject, the ICD being in communication with a control unit that drives the application of the current.

50. The method according to claim 49, wherein applying the current comprises applying the current responsively to determining that a heart rate of the subject is greater than a threshold value that is greater than a normal heart rate.

51. A method for treating a subject, comprising:

determining that a heart rate of the subject is greater than a threshold value that is greater than a normal heart rate;

responsively to the determination, applying a current to a site of the subject selected from;

a vagus nerve and an epicardial fat pad; and

configuring the current so as to treat a condition of the subject selected from;

atrial arrhythmia, and atrial arrhythmia combined with heart failure.