Electrical stimulation and thrombolytic therapy

• US 20040039417A1
• Filed: 04/15/2003
• Published: 02/26/2004
• Est. Priority Date: 04/16/2002
• Status: Abandoned Application

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Soykan, Orhan, Williams, Terrell M., Donovan, Maura G., Trescony, Paul V., Robinson, Timothy H., Deno, Curtis D.
• Application Number:
  US10/414,382
• Publication Number:
  US 20040039417A1
• Time in Patent Office: Days
• US Class Current: 607/2
• CPC Class Codes: A61N 1/326 for promoting growth of cells, e.g. bone cells

Abstract

This invention is an electrical stimulation apparatus for delivering an electrical field or electrical current over a predetermined period of time to a vascular tissue (150) in order to stimulate a cell initiated thrombolytic peptide response in cells within the vascular tissue. The electrical stimulation apparatus includes an electrical field or electrical current generating unit including a power support, a control mechanism interconnected with the power supply, and a plurality of electrodes designed to generate an electrical field or electrical current proximal to, or within to the vascular tissue. The amplitude of the electrical field or electrical current delivered to or generated proximal to, or within the vascular tissue, and the duration of the period of delivery are sufficient to stimulate production of thrombolytic peptides in the vascular tissue. The control mechanism preferably includes a computer processing unit in electronic communication with the power supply, the computer being programmed to cause the electrical stimulation apparatus to deliver a predetermined amount of electrical current or voltage over a predetermined period of delivery to the plurality of electrodes such that the electrical stimulation apparatus can deliver such electrical current or voltage to the vascular tissue when the plurality of electrodes are in contact or proximity with the vascular tissue.

Claims

1. An electrical stimulation apparatus for controlled production of thrombolytic peptides comprising:

an electrical field or electrical current generating unit including a power supply and a control mechanism interconnected with the power supply; and

a plurality of electrodes designed to deliver an electrical field or electrical current to the vascular tissue

wherein the plurality of electrodes are in proximity with the vascular tissue at a plurality locations such that an electrical field or electrical current can be generated between the respective electrodes, wherein the amplitude of the electrical field or electrical field delivered to the vascular tissue and the duration of the period of delivery is sufficient to stimulate production of said thrombolytic peptides from the vascular tissue.

3. The electrical stimulation apparatus of either claim 1 or 2, wherein the control mechanism includes a computer processing unit in electronic communication with the power supply, the computer being programmed to cause the electrical stimulation apparatus to deliver a predetermined amount of electrical current or voltage over a predetermined period of delivery to the plurality of electrodes such that the electrical stimulation apparatus can deliver such electrical current or voltage to the vascular tissue when the plurality of electrodes are in contact or proximity with the vascular tissue.

4. The electrical stimulation apparatus of either claim 1 or 2, wherein the electrical field or electrical current generating unit is a biphasic pulsating current delivery device and the amplitude of a current delivered to the vascular tissue is from about 0.1 V to 25V.

5. The electrical stimulation apparatus of either claim 1 or 2, wherein the electrical field or electrical current generating unit is a biphasic pulsating voltage delivery device, and the delivered current density is from about 30 to 600 μ

A/mm².

6. The electrical stimulation apparatus of either claim 1 or 2, wherein the electrical field or electrical current is produced by a number of pulses with a frequency between about 1 Hz to about 10 Hz.

7. The electrical stimulation apparatus of either claim 1 or 2, wherein the electrical field or electrical current is produced for a duration between about 1 to 20 msec.

8. The electrical stimulation apparatus of either claim 1 or 2, wherein the plurality of electrodes are configured in a manner selected from the group consisting of unipolar, bipolar, and multiple electrode configurations.

9. The electrical stimulation apparatus of claim 1, wherein the apparatus is designed and configured to be implantable.

10. The electrical stimulation apparatus of either claim 1 or 2, the plurality of electrodes including a sensing electrode, wherein the vascular tissue supplies the heart and the sensing electrode monitors contractions of the heart and communicates information regarding the contractions to the computer processing unit so that the computer processing unit can synchronize the period of delivery with a series of refractory periods which follow contractions of the heart, the electrical field or electrical current being delivered to the heart in a series of pulses programmed to be synchronized with the occurrence of the series of refractory periods.

11. The electrical stimulation apparatus of claim 9, wherein the sensing electrode includes heart pacemaking capabilities which allow it to pace the heart to facilitate the synchronization of the pulsed electrical field or electrical current generation with the occurrence of the refractory period.

12. The electrical stimulation apparatus of claim 10, wherein the control mechanism includes a computer processing unit in electronic communication with the power supply, the computer being programmed to cause the electrical stimulation apparatus to deliver a predetermined amount of electrical current or voltage over a predetermined period of delivery to the plurality of electrodes such that the electrical stimulation apparatus can deliver such electrical current or voltage to the vascular tissue when the plurality of electrodes are in contact or proximity with the vascular tissue.

13. The electrical stimulation apparatus of claim 1, wherein the stimulation wave field is selected from the group consisting of rectangular and exponential decay.

14. The electrical stimulation apparatus of claim 1 wherein the period of electrical stimulation is from about 1 msec to several days.

15. The electrical stimulation apparatus of either claim 1 or 2 wherein the electrical field or electrical current delivered to stimulate increased tPA production is without significant cellular death.

16. The electrical stimulation apparatus of either claim 1 or 2 wherein the electrical field or electrical current produced is charged balanced.

50. The electrical stimulation apparatus of either claim 1 or 2, wherein the current density is 60 mAmp/mm2 of the endothelial surface area.

2. An electrical stimulation apparatus for delivering an electrical field or electrical current over a predetermined period of time to a vascular tissue in order to stimulate production of tPA expression within the vascular tissue the electrical stimulation apparatus comprising:

an electrical field or electrical current generating unit including a power supply and a control mechanism interconnected with the power supply; and

a plurality of electrodes designed to deliver an electrical field or electrical current to the vascular tissue;

wherein the plurality of electrodes are in electrical communication with the power supply;

the control mechanism controlling an amplitude and a duration of a period of delivery of electrical pulses from the power supply to the respective electrodes and to the vascular tissue when the plurality of electrodes are in proximity with the vascular tissue at a plurality locations such that an electrical field or electrical or electrical current can be generated between the respective electrodes, wherein the amplitude of the electrical field or electrical current delivered to the vascular tissue and the duration of the period of delivery is sufficient to cause cells in the vascular tissue to have increased tPA expression.

17. A vascular electrode system comprising a plurality of parallel stimulating electrodes attached to a common base plate which can be conformed to the vascular structure by wrapping said electrodes around the vasculature.

18. A vascular electrode system of claim 17, wherein the plurality of stimulating parallel electrodes comprises at least 5 electrodes attached to the common base plate.

19. A vascular electrode system of claim 17, wherein the plurality of parallel electrodes comprises at least 10 electrodes attached to the common base plate.

20. A vascular electrode system of claim 17 wherein the return electrode is part of the base.

21. A vascular electrode system of claim 17 wherein the return electrode member comprises at least one electrically isolated parallel electrode member attached to the base plate.

22. A vascular electrode system of claim 17 wherein the return electrode is placed at a distant site from the plurality of stimulating electrode members.

23. A vascular electrode system of claim 17 wherein the plurality of stimulating electrode members may vary in contact distance or spacing from the adjacent electrode member.

24. A vascular electrode system of claim 17 produces a uniform current density with minimal variation in the longitudinal axis.

25. A vascular electrode system of claim 17 wherein the current is evenly distributed in the radial direction across the stimulating electrodes.

26. A vascular electrode system of claim 17 wherein the plurality of stimulating electrodes are spaced to delivery a uniform current density in the longitudinal axis to the vascular tissue.

27. A vascular electrode system of claim 17 wherein the plurality of stimulating electrodes are spaced to deliver current evenly in the radial direction to the vascular tissue.

28. A method of thrombolytic therapy comprising the step of stimulating the vascular tissue with an electrical field or electrical current sufficient to stimulate production of at least one thrombogenic peptide in the vascular tissue when the vascular tissue is electrically stimulated, wherein the amplitude of the electrical field or electrical current delivered to the vascular tissue and the duration of the period of delivery is sufficient to cause cells in the vascular tissue to increase tPA expression.

31. The method of treatment of vascular tissues of any one of claims 28, 29, or 30, wherein the electrical field or electrical current generating unit is a biphasic pulsating current delivery device, the amplitude of the delivered current is from about 0.1 V to about 25V.

32. The method of treatment of vascular tissues of any one of claims 28, 29, or 30, wherein the electrical field or electrical current is a biphasic pulsating voltage delivery device, and the delivered current density is from about 30 to 600 μ

A/mm².

33. The method of treatment of vascular tissues of any one of claims 28, 29, or 30, wherein the electrical field or electrical current is produced by a number of pulses in the range of about 1 Hz to about 10 Hz.

34. The method of treatment of vascular tissues of any one of claims 28, 29, or 30, wherein the electrical field or electrical current is produced for a duration of between about 1 to 20 msec.

35. The method of treatment of vascular tissues of any one of claims 28, 29, or 30, wherein the plurality of electrodes are configured in a manner selected from the group consisting of unipolar, bipolar, and multiple electrode configurations.

36. The method of treatment of vascular tissues of any one of claims 28, 29, or 30, wherein the apparatus is designed and configured to be implantable.

37. The method of treatment of vascular tissues of any one of claims 28, 29, or 30;

wherein at least one of the plurality of electrodes is different from the first location.

39. The method of claim 37 wherein the transplanted cells have been stimulated ex vivo prior to being injected into the vascular tissue.

40. The method of claim 37 wherein the transplanted cells are autologous.

41. The method of claim 37 wherein the transplanted cells are allogenic.

42. The method of claim 37 wherein the transplanted cells are xenogenic.

43. The method of claim 37 wherein the transplanted cells are endothelial cells.

44. The method of claim 37 wherein the transplanted cells have been genetically engineered.

45. The method of claim 43 wherein the genetically engineered cells have been transfected with an additional tPA gene.

29. A method of thrombolytic therapy comprising the step of stimulating the vascular tissue with an electrical field or electrical current sufficient to stimulate production of at least one thrombogenic peptide in the vascular tissue when the vascular tissue is electrically stimulated, wherein the amplitude of the electrical field or electrical current delivered to the vascular tissue and the duration of the period of delivery is sufficient to alter thrombus formation.

30. The method of treatment of vascular tissues of wherein the electrical stimulation apparatus comprises:

an electrical field or electrical current generating unit including a power supply and a control mechanism interconnected with the power supply; and

a plurality of electrodes designed to deliver an electrical field or electrical current to the vascular tissue;

wherein the plurality of electrodes are in proximity with the vascular tissue at a plurality locations such that an electrical field or electrical current can be generated between the respective electrodes, wherein the amplitude of the electrical field or electrical current delivered to the vascular tissue and the duration of the period of delivery are sufficient to stimulate the desired thrombolytic response.

38. A method of treatment of vascular tissues in which increased vascularization is desirable;

said method of treatment comprising the steps of;

transplanting cells which are biologically compatible with the vascular tissue; and

stimulating the cells with an electrical field or electrical current sufficient to increase tPA expression of the cells;

wherein the amplitude of the electrical field or electrical current delivered to the vascular tissue and the duration of the period of delivery are sufficient to cause the transplanted cells to increase tPA expression.

46. A method of treating a myocardial infarction comprising:

providing an electrical field or electrical current generating unit including a power supply and a control mechanism interconnected with the power supply; and

a plurality of electrodes designed to deliver an electrical field or electrical current to the vascular tissue;

wherein the plurality of electrodes are in proximity with the vascular tissue at a plurality locations such that an electrical field or electrical current can be generated between the respective electrodes, wherein the amplitude of the electrical field or electrical current delivered to the vascular tissue and the duration of the period of delivery are sufficient to stimulate the desired thrombolytic response.

47. A method of treating a stroke comprising:

providing an electrical field or electrical current generating unit including a power supply and a control mechanism interconnected with the power supply; and

a plurality of electrodes designed to deliver an electrical field or electrical current to the vascular tissue;

wherein the plurality of electrodes are in proximity with the vascular tissue at a plurality locations such that an electrical field or electrical current can be generated between the respective electrodes, wherein the amplitude of the electrical field or electrical current delivered to the vascular tissue and the duration of the period of delivery are sufficient to stimulate the desired thrombolytic response.

48. A method of treating an ischemic neuropathy comprising:

providing an electrical field or electrical current generating unit including a power supply and a control mechanism interconnected with the power supply; and

a plurality of electrodes designed to deliver an electrical field or electrical current to the vascular tissue;

wherein the plurality of electrodes are in proximity with the vascular tissue at a plurality locations such that an electrical field or electrical current can be generated between the respective electrodes, wherein the amplitude of the electrical field or electrical current delivered to the vascular tissue and the duration of the period of delivery are sufficient to stimulate the desired thrombolytic response.

49. A method of use with placement of an arteriovenous shunt comprising:

providing an electrical field or electrical current generating unit including a power supply and a control mechanism interconnected with the power supply; and

a plurality of electrodes designed to deliver an electrical field or electrical current to the vascular tissue;

wherein the plurality of electrodes are in proximity with the vascular tissue at a plurality locations such that an electrical field or electrical current can be generated between the respective electrodes, wherein the amplitude of the electrical field or electrical current delivered to the vascular tissue and the duration of the period of delivery are sufficient to stimulate the desired thrombolytic response.