Stimulation system, in particular a cardiac pacemaker

• US 8,321,021 B2
• Filed: 07/11/2008
• Issued: 11/27/2012
• Est. Priority Date: 01/13/2006
• Status: Expired due to Fees

• Current Assignee: Universitat Duisburg-Essen
• Original Assignee: Universitat Duisburg-Essen
• Inventors: Kisker, Erhard, WIENEKE, Heinrich
• Primary Examiner(s): Layno, Carl H.
• Assistant Examiner(s): MORALES, JON ERIC C
• Application Number:
  US12/171,955
• Publication Number:
  US 20090024180A1
• Time in Patent Office: 1,600 Days
• Field of Search: 607/2, 607/9, 607/32, 607/33, 607/37, 607/126
• US Class Current: 607/32
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

A stimulation system, an implantable electrode device and a method for operating an implantable electrode device are proposed. A simplified implantation, a simple construction and reliable control are made possible by the electrode device being supplied with energy, and controlled, in an exclusively wireless manner via a time-variable magnetic field. The magnetic field is generated by an implanted control device.

Claims

1. A stimulation system comprising an implantable control device and an implantable electrode device for generating electrical impulses, which can be supplied with energy and controlled by the control device in an exclusively wireless manner by means of a time-varying magnetic field, the control device being configured such that the field strength of the magnetic field, at least during switch-on times, has a substantially ramp- or sawtooth-shaped time profile or is bipolar or pulsed;

and

wherein the stimulation system is configured in such a manner that in the switched-on state the magnetic field is formed by a plurality of unipolar or bipolar magnetic field pulses and/or that the respective switch-on duration of the magnetic field controls or determines the length of each electrical impulse of a stimulation generated by the electrode device and/or the magnetic field is utilized for energy recovery.

2. The stimulation system according to claim 1, wherein the control device is configured such that the magnetic field is at least of generated intermittently and comprises a switch-on ratio of:

less than 0.5;

less than 0.25;

or

less than approximately 0.1.

3. The stimulation system according to claim 1, wherein the control device is configured in such a manner that the magnetic field is alternately generated with an opposite field direction for the alternate generation of an electrical impulse and activating the electrode device before generating the next electrical impulse, in particular wherein the activation takes place shortly before generation of the next electrical impulse.

4. The stimulation system according to claim 1, wherein the frequency of the magnetic field is less than 3 Hz or corresponds to the desired frequency of the electrical impulses to be generated.

5. The stimulation system according to claim 1, wherein the control device is configured in such a manner that the field strength of the magnetic field in the region of the electrode device is substantially 1 to 20 mT.

6. The stimulation system according to claim 1, wherein the control device in the implanted state can be charged inductively from outside.

7. The stimulation system according to claim 1, wherein the stimulation system is a cardiac pacemaker.

8. The stimulation system according to claim 1, wherein the electrode device is configured in such a manner that an electrical impulse can be generated in each case only following previous activation, in particular by exceeding a second minimum field strength of the magnetic field having the opposite field direction to the field direction for the generation of an electrical impulse, in particular wherein the second minimum field strength is greater than the first minimum field strength.

9. The stimulation system according to claim 1, wherein the electrode device comprises a coil device which generates a pulse-like induction voltage when a first minimum field strength of the magnetic field is exceeded, in particular wherein the coil device comprises at least one of a coil core or a core element having a magnetization which varies abruptly depending on the acting magnetic field strength and a wire-like layer arrangement of soft and hard magnetic material.

10. The stimulation system according to claim 1, wherein the electrode device comprises a coil device, wherein an electrical impulse having a voltage of at least 0.5 V and a time duration of at least 0.05 ms can be generated by the coil device by at least one of an external and a varying magnetic field having a field strength in the region of the electrode device of at most 10 mT.

11. The stimulation system according to claim 1, wherein the electrode device preferably comprises only a passively operating pulse forming device, in particular having at least one of an inductance, a capacitance and a resistance, wherein the electrode device is configured as at least one of a battery-less and amplifier-less device, wherein the electrode device comprises a coil device with a magnetic core, the core being magnetically soft or ultra-soft.

12. The stimulation system according to claim 1, wherein the electrode device is configured such that each pulse-like induction voltage is output as an electrical impulse via integrated electrodes.

13. The stimulation system according to claim 1, wherein the electrode device comprises a coil device with a magnetic core, the core being at least one of magnetically soft and ultra-soft.

14. An implantable electrode device for a stimulation system for generating electrical impulses, wherein the electrode device is configured as at least one of a wireless and a compact structural unit, and can be supplied with energy and directly controlled exclusively by means of a varying magnetic field, wherein the electrode device is configured in such a manner that an electrical impulse is only generated when a first minimum field strength of the magnetic field is exceeded.

15. The electrode device according to claim 14, wherein the electrode device is configured in such a manner that an electrical impulse can be generated in each case only following previous activation.

16. The electrode device according to claim 15, wherein an electrical impulse can be generated in each case only following previous activation, by exceeding a second minimum field strength of the magnetic field having the opposite field direction to the field direction for the generation of an electrical impulse.

17. The electrode device according to claim 14, wherein the minimum field strength is substantially 0.5 to 20 mT.

18. The electrode device according to claim 14, wherein the electrode device comprises a coil device which generates a pulse-like induction voltage when a first minimum field strength of the magnetic field is exceeded, wherein the coil device has a coil core or a core element having a magnetization which varies abruptly depending on the acting magnetic field strength or having a layer arrangement of soft and hard magnetic material.

19. The electrode device according to claim 14, wherein the electrode device comprises a coil device, wherein an electrical impulse having a voltage of at least 0.5 V and a time duration of at least 0.05 ms can be generated by the coil device by at least one of an external and a varying magnetic field having a field strength in the region of the electrode device of at most 10 mT.

20. The electrode device according to claim 14, wherein the electrode device preferably comprises at least one of a passively operating pulse forming device, in particular having at least one of an inductance, a capacitance and a resistance;

the electrode device is configured as at least one of a battery-less and amplifier-less device; and

the electrode device comprises a coil device with a magnetic core, the core being magnetically soft or ultra-soft.

21. The electrode device according to claim 14, wherein the electrode device is configured such that each pulse-like induction voltage is output as an electrical impulse.

22. The electrode device according to claim 14, wherein the frequency of the magnetic field is less than 3 Hz or corresponds to the desired frequency of the electrical impulses to be generated.

23. The electrode device according to claim 14, wherein the electrode device is configured in such a manner that it generates and delivers an electrical impulse each time the minimum field strength is exceeded.

24. The electrode device according to claim 14 wherein the electrode device is a cardiac pacemaker.

25. The electrode device according to claim 14 wherein the electrode device comprises only passive components and a rectifier.

26. The electrode device according to claim 14, wherein the electrode device comprises a coil device, wherein the coil device comprises at least 1,000 turns.

27. A method comprising:

operating an implantable electrode device for generating electrical impulses, wherein the electrode device is supplied with energy and directly controlled by means of a magnetic field to generate the electrical impulses, wherein the magnetic field in a switched-on state is formed by a plurality of unipolar or bipolar magnetic field pulses and that a respective switch-on time of the magnetic field controls or determines the length of the electrical impulse respectively generated by the electrode device or during a contiguous sequence of electrical impulses,

wherein the number of magnetic field impulses is varied for a variation of the duration of each electrical impulse or a contiguous sequence of electrical impulses or wherein the magnetic impulses have a substantially sawtooth-shaped profile.

28. The method according to claim 27, wherein the magnetic field has a switch-on ratio of less than 0.5 or less than 0.25 or substantially 0.1 or less.

29. The method according to claim 27, wherein the magnetic field is at least one of generated intermittently and has a switch-on ratio of less than 0.5 or less than 0.25 or substantially 0.1 or less.

30. The method according to claim 27, wherein the magnetic field is alternately generated with an opposite field direction for the alternate generation of an electrical impulse and the electrode device is activated before generating the next electrical impulse, in particular wherein the activation takes place shortly before generation of the next electrical impulse.

31. The method according to claim 30, wherein the activation takes place shortly before generation of the next electrical impulse.

32. The method according to claim 30, wherein an electrical impulse is generated and delivered each time the minimum field strength is exceeded.

33. The method according to claim 27, wherein the frequency of the magnetic field is less than 3 Hz or corresponds to the desired frequency of the electrical impulses to be generated.

34. The method according to claim 27, wherein at least one of:

in the switched-on state the magnetic field is formed by a plurality of unipolar or bipolar magnetic field pulses;

a respective switch-on duration of the magnetic field controls or determines the length of each electrical impulse of a stimulation generated by the electrode device; and

the magnetic field is utilized for energy recovery.

35. The method according to claim 27, wherein the field strength of the magnetic field in the region of the electrode device is substantially 1 to 20 mT, in particular 2 to 10 mT.

36. The method according to claim 27, wherein an electrical impulse is only generated when a first minimum field strength of the magnetic field is exceeded.

37. The method according to claim 27, wherein an electrical impulse can be generated in each case only following previous activation by exceeding a second minimum field strength of the magnetic field having the opposite field direction to the field direction for the generation of an electrical impulse.

38. The method according to claim 27, wherein an electrical impulse can be generated in each case only following previous activation by exceeding a second minimum field strength of the magnetic field, wherein the second minimum field strength is greater than the first minimum field strength;

or

wherein the minimum field strength is substantially 0.5 to 20 mT.

39. The method according to claim 27, wherein a pulse-like induction voltage is generated when a first minimum field strength of the magnetic field is exceeded wherein the coil device comprises at least one of a coil core or a core element having a magnetization which varies abruptly depending on the acting magnetic field strength and a wire-like layer arrangement of soft and hard magnetic material.

40. The method according to claim 27, wherein a pulse-like induction voltage is generated when a first minimum field strength of the magnetic field is exceeded;

and

wherein each pulse-like induction voltage is output as an electrical impulse.

41. The method according to claim 27, wherein the electrode device comprises a coil device, wherein an electrical impulse having a voltage of at least 0.5 V and a time duration of at least 0.05 ms can be generated by the coil device by at least one of an external and a varying magnetic field having a field strength in the region of the electrode device of at most 10 mT.

42. The method according to claim 27, wherein the electrode device is a cardiac pacemaker.

43. The method according to claim 27, wherein the electrode device comprises a coil device comprising at least 1,000 turns.

44. A method comprising:

operating an implantable electrode device for generating electrical impulses, wherein the electrode device is supplied with energy and directly controlled by means of a magnetic field to generate the electrical impulses, wherein the magnetic field in a switched-on state is foamed by a plurality of unipolar or bipolar magnetic field pulses and that a respective switch-on time of the magnetic field controls or determines the length of the electrical impulse respectively generated by the electrode device or during a contiguous sequence of electrical impulses,

wherein the field strength of the magnetic field, at least during switch-on times, has a substantially ramp- or sawtooth-shaped time profile.

45. The method according to claim 44, wherein the electrode device is a cardiac pacemaker.

46. The method according to claim 44, wherein the magnetic field has a switch-on ratio of less than 0.5.

47. The method according to claim 44, wherein at least one of the magnetic field is generated intermittently, and the magnetic field has a switch-on ratio of:

less than 0.5;

less than 0.25;

or

approximately 0.1 or less.

48. The method according to claim 44, wherein the magnetic field is alternately generated with an opposite field direction for the alternate generation of an electrical impulse and the electrode device is activated before generating the next electrical impulse, in particular wherein the activation takes place shortly before generation of the next electrical impulse.

49. The method according to claim 44, wherein the frequency of the magnetic field is less than 3 Hz, and in particular corresponds to the desired frequency of the electrical impulses to be generated.

50. The method according to claim 44, wherein at least one of in the switched-on state the magnetic field is formed by a plurality of unipolar or bipolar magnetic field pulses, the respective switch-on duration of the magnetic field controls or determines the length of each electrical impulse of a stimulation generated by the electrode device, and the magnetic field is utilized for energy recovery.

51. The method according to claim 44, wherein the field strength of the magnetic field in the region of the electrode device is substantially 1 to 20 mT, in particular 2 to 10 mT.

52. The method according to claim 44, wherein an electrical impulse is only generated when a first minimum field strength of the magnetic field is exceeded, preferably wherein an electrical impulse is generated and delivered each time the minimum field strength is exceeded, preferably only after a respective preceding activation.

53. The method according to claim 44, wherein an electrical impulse can be generated in each case only following previous activation, in particular by exceeding a second minimum field strength of the magnetic field having the opposite field direction to the field direction for the generation of an electrical impulse, in particular wherein the second minimum field strength is greater than the first minimum field strength.

54. The method according to claim 44, wherein a pulse-like induction voltage is generated when a first minimum field strength of the magnetic field is exceeded, in particular wherein the coil device has a coil core or a core element comprises at least one of a magnetization which varies abruptly depending on the acting magnetic field strength and a wire-like layer arrangement of soft and hard magnetic material.

55. The method according to claim 44, wherein the electrode device comprises a coil device, wherein an electrical impulse having a voltage of at least 0.5 V and a time duration of at least 0.05 ms can be generated by the coil device by at least one of an external and varying magnetic field having a field strength in the region of the electrode device of at most 10 mT, in particular substantially 2 mT or less and wherein the coil device comprises at least 1,000 turns.

56. The method according to claim 44, wherein an electrical impulse can be generated in each case only following previous activation by exceeding a second minimum field strength of the magnetic field having the opposite field direction to the field direction for the generation of an electrical impulse wherein the second minimum field strength is greater than the first minimum field strength or wherein the minimum field strength is substantially 0.5 to 20 mT.

57. The method according to claim 44, wherein a pulse-like induction voltage is generated when a first minimum field strength of the magnetic field is exceeded;

and

wherein each pulse-like induction voltage is output as an electrical impulse.