Expandable catheter having two sets of electrodes

• US 6,179,832 B1
• Filed: 08/21/1998
• Issued: 01/30/2001
• Est. Priority Date: 09/11/1997
• Status: Expired due to Term

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: VNUS Medical Technologies Incorporated (Medtronic Plc)
• Inventors: Jones, Christopher S., Zikorus, Arthur W., Parker, Mark P., Farley, Brian E., Tartaglia, Joseph M.
• Primary Examiner(s): Peffley, Michael
• Assistant Examiner(s): ROLLINS, ROSILAND STACIE
• Application Number:
  US09/138,472
• Time in Patent Office: 893 Days
• Field of Search: 606/32, 606/34, 606/37, 606/38, 606/39, 606/40, 606/41, 606/42, 606/45, 606/46, 606/47-50, 607/96, 607/98, 607/99, 607/101, 607/104, 607/105, 607/106, 607/113
• US Class Current: 606/32
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2017/22038 with a guide wire
• CPC Class Codes: A61B 2017/22051 with an inflatable part, e.g. balloon, for positioning, blocking, or immobilisation A61B2017/22048, A61B2017/3486 take precedence
• CPC Class Codes: A61B 2017/22067 Blocking; Occlusion A61B2017/22054 takes precedence
• CPC Class Codes: A61B 2018/00214 Expandable means emitting energy, e.g. by elements carried thereon
• CPC Class Codes: A61B 2018/0022 Balloons
• CPC Class Codes: A61B 2018/00404 Blood vessels other than those in or around the heart
• CPC Class Codes: A61B 2018/00488 Esophagus
• CPC Class Codes: A61B 2018/00589 Coagulation
• CPC Class Codes: A61B 2018/00898 Alarms or notifications created in response to an abnormal condition
• CPC Class Codes: A61B 2018/124 switching the output to different electrodes, e.g. sequentially
• CPC Class Codes: A61B 2018/1253 monopolar
• CPC Class Codes: A61B 2018/126 bipolar
• CPC Class Codes: A61B 2090/3782 transmitter or receiver in catheter or minimal invasive instrument
• CPC Class Codes: A61B 2218/002 Irrigation

Abstract

A catheter includes a first plurality of expandable leads and a second plurality of expandable leads separate and longitudinally spaced-apart from the first plurality to deliver energy to a hollow anatomical structure, such as vein, fallopian tube, hemorrhoid, esophageal varix, to effectively ligate that structure. Each of the leads includes an electrode located at the distal end of the respective electrode lead. Polarizations of the leads may be selected to achieve the power distribution desired. Each electrode lead includes an outward bend such that when a movable sheath is moved out of contact with the leads, they expand outwardly into apposition with an inner wall of the structure to be ligated. High frequency energy can be applied from the leads to create a heating effect in the surrounding tissue of the anatomical structure. The diameter of the hollow anatomical structure is reduced by the heating effect, and the electrodes are freely moved inward by the shrinking structure while still maintaining apposition with the inner wall of the shrinking structure.

Claims

1. Apparatus for applying energy to a hollow anatomical structure comprising:

a catheter having a shaft with a working end at which energy is applied to the structure;

a first plurality of expandable arms mounted to the working end of the catheter at a first location, each arm having an electrode;

a second plurality of expandable arms mounted to the working end of the catheter at a second location that is separate from and longitudinally spaced apart from the first location at which the first plurality is mounted, the second plurality being configured to expand independently from the first plurality, each arm having an electrode;

wherein each arm has a blunt distal end;

wherein the arms of the first and second pluralities each have an expanded position at which the electrode is located outward from the catheter shaft and a contracted position at which the electrode is located nearer the shaft; and

a deployment device mounted to the catheter, the deployment device having a first position at which selected electrodes are in the contracted position and a second position at which the electrodes are in the expanded position.

2. The apparatus of claim 1 wherein the arms are mounted at the working end in a cantilever arrangement.

3. The apparatus of claim 1 wherein the arms of the first and second pluralities are disposed in relation to the working end such that when in the expanded position, the electrodes of the arms form a substantially symmetric arrangement of substantially evenly spaced electrodes.

4. The apparatus of claim 1 wherein:

each arm is formed of an electrically conductive material insulated along its length; and

each arm includes an outwardly-facing portion at which no insulation is present thereby forming the electrode.

5. The apparatus of claim 1 wherein:

the arms are formed of a material having a strength selected such that when the sheath is in its second position, the arms are strong enough to move into apposition with the hollow anatomical structure; and

the arms have a strength such that they permit the hollow anatomical structure to shrink but remain in apposition with the shrinking structure.

6. The apparatus of claim 1 further comprising:

a power source connected to the electrodes;

a controller that controls the power source; and

a temperature sensor mounted to an arm, the temperature sensor providing temperature signals to the controller;

wherein the controller controls the power source in response to the temperature signals.

7. The apparatus of claim 1 further comprising:

a power source connected to the electrodes; and

a controller adapted to;

control the output of the power source to the electrodes such that adjacent electrodes of the first plurality of arms are of opposite polarities while maintaining the polarity of the second plurality of electrodes so that they are electrically neutral;

switch the polarity of the electrodes of the first plurality of arms so that they are all of the same polarity upon collapse of the hollow anatomical structure around the first plurality of arms; and

control the power source so that the electrodes of the second plurality of arms are of opposite polarity relative to the electrodes of the first plurality of arms upon performing the step of switching the polarity of the electrodes so that they are of the same polarity.

8. The apparatus of claim 1 wherein:

each of the arms of the first and second pluralities is formed with an outward bend that tends to expand the distal portion of each arm outwardly;

each of the arms is formed of an electrically conductive material having a strength selected such that when the sheath is in the second position, the arms are strong enough to move into apposition with the hollow anatomical structure, and the arms have a strength such that they permit the hollow anatomical structure to shrink while the electrodes remain in apposition with the anatomical structure; and

each arm is insulated along its length, and each arm includes an outwardly-facing portion at which no insulation is present thereby forming the electrode which is configured to come into apposition with the hollow anatomical structure.

9. The apparatus of claim 1 wherein the arms are configured such that when in the expanded position, they form an acute angle with the catheter shaft.

10. The apparatus of claim 1 wherein:

the arms of the first plurality are formed such that they are self-biased outwardly from the catheter shaft;

wherein the deployment device comprises a movable sheath having a first position at which the sheath surrounds the first plurality of arms over at least a portion thereof and confines the surrounded arms to the contracted position, the movable sheath having a second position at which a plurality of arms is permitted to expand outwardly to the expanded position.

11. The apparatus of claim 10 wherein:

the arms of the second plurality are formed such that they are self-biased outwardly from the catheter shaft;

the movable sheath at its first position also surrounds the second plurality of arms over at least a portion thereof and confines the surrounded arms to the contracted position; and

the movable sheath at its second position permits the second plurality of arms to expand outwardly to the expanded position.

12. The apparatus of claim 10 further comprising a fluid delivery lumen between the catheter shaft and the movable sheath.

13. The apparatus of claim 1 wherein each of the arms of the first and second pluralities is formed with an outward bend that provides a bias to each arm and tends to expand the distal portion of each arm outwardly.

14. The apparatus of claim 13 wherein:

the second location at which the second plurality of arms is mounted to the working end of the catheter is proximal to the first location;

the movable sheath at its first position in relation to the first plurality of arms is distal to the bends of the first plurality of arms thereby retaining the first and second pluralities in the contracted position, the movable sheath at its second position is proximal to the bends of the first and second pluralities thereby permitting the first and second pluralities to expand outwardly to the expanded position.

15. The apparatus of claim 1 further comprising a guide wire lumen configured to accept a guide wire.

16. The apparatus of claim 15 wherein the guide wire lumen is capable of being connected to a fluid delivery system.

17. The apparatus of claim 1 wherein the first plurality of arms are mounted to a first electrically-conductive mounting ring to which the electrodes of those arms are electrically inter-connected.

18. The apparatus of claim 17 wherein the second plurality of arms are mounted to a second electrically-conductive mounting ring to which the electrodes of those arms are electrically inter-connected.

19. The apparatus of claim 18 further comprising a third electrically-conductive mounting ring to which alternating arms of a selected one of the pluralities of arms are mounted thereby resulting in adjacent electrodes of the selected plurality being electrically inter-connected to different mounting rings.

20. The apparatus of claim 19 further comprising a fourth electrically-conductive mounting ring to which alternating arms of the other of the pluralities of arms are mounted thereby resulting in adjacent electrodes of both pluralities being electrically inter-connected to different mounting rings.

21. The apparatus of claim 19 further comprising:

a power source connected to the mounting rings;

a controller that controls the power source; and

a switch connected to the controller, the switch having a first position at which the controller applies different polarities to the first and third mounting rings, and a second position at which the controller applies the same polarity to the first and third mounting rings.

22. The apparatus of claim 1 further comprising:

a power source connected to the electrodes; and

a controller that controls the output of the power source to the electrodes;

wherein the controller is adapted to switch the electrical polarity of the electrodes as selected.

23. The apparatus of claim 22 wherein the controller is further adapted to:

control the power source so that adjacent electrodes of the first plurality are of opposite polarity;

control the power source so that adjacent electrodes of the second plurality are of opposite polarity; and

control the power source so that the polarities of the electrodes of the second plurality are selected so that opposite polarities are longitudinally aligned with the electrodes of the first plurality.

24. The apparatus of claim 22 further comprising:

a backplate located at a surface of the patient;

wherein the controller is further adapted to;

control the energy applied to at least one of the pluralities of electrodes so that the electrodes are of a first polarity; and

control the energy applied to the backplate so that it is a second polarity.

25. The apparatus of claim 24 wherein the controller is adapted to control the energy applied to the other of the pluralities of electrodes so that the electrodes of that plurality are of the first polarity.

26. The apparatus of claim 1 wherein the blunt distal ends of the arms are rounded.

27. The apparatus of claim 26 wherein the electrodes are located at the blunt distal ends of the arms and the electrodes have an approximate hemispherical shape.

29. The apparatus of claim 21 wherein:

each arm is formed of an electrically conductive material insulated along its length; and

each arm includes an outwardly-facing portion at which no insulation is present thereby forming an electrode.

28. Apparatus for applying energy to biological tissue, comprising:

a catheter having a shaft with a working end at which energy is applied to the tissue;

a first plurality of expandable arms mounted to the working end of the catheter at a first location, each arm having an electrode;

a second plurality of expandable arms mounted to the working end of the catheter at a second location that is separate from and longitudinally spaced apart from the first location at which the first plurality is mounted, the second plurality being configured to expand independently from the first plurality, each arm having an electrode;

wherein each arm has a blunt distal end;

wherein each arm comprises an outward bend such that the arm tends to move outwardly distal to the bend;

wherein each plurality of electrode arms forms a substantially symmetric arrangement of substantially evenly-spaced electrodes when expanded, the expanded electrodes of the first plurality being longitudinally spaced apart from the expanded electrodes of the second plurality, and each plurality of electrode arms having a contracted position at which the arms are located nearer the shaft; and

a movable sheath having a first position at which the sheath surrounds the first and second pluralities of arms over at least a portion thereof and confines the surrounded arms to the contracted position, the movable sheath having a second position at which pluralities of arms are permitted to expand outwardly to an expanded position.

30. The apparatus of claim 28 further comprising:

a power source connected to the electrodes;

a controller that controls the power source; and

a temperature sensor mounted to an arm, the temperature sensor providing temperature signals to the controller;

wherein the controller controls the power source in response to the temperature signals.

31. The apparatus of claim 28 further comprising:

a power source connected to the electrodes; and

a controller that controls the output of the power source to the electrodes;

wherein the controller is adapted to switch the electrical polarity of the electrodes as selected.

32. The apparatus of claim 28 further comprising a fluid delivery lumen between the catheter shaft and the movable sheath.

33. The apparatus of claim 28 wherein the arms are configured such that when in the expanded position, they form an acute angle with the catheter shaft.

34. The apparatus of claim 28 further comprising:

a first electrically-conductive mounting ring to which the first plurality of arms is mounted; and

a second electrically-conductive mounting ring to which the second plurality of arms is mounted;

wherein both first and second mounting rings provide common electrical connections for the respective electrodes of the respective arms connected thereto.

35. The apparatus of claim 34 further comprising a third electrically-conductive mounting ring to which alternating arms of a selected one of the pluralities of arms are electrically interconnected thereby resulting in adjacent arms of the selected plurality being connected to different mounting rings.

36. The apparatus of claim 35 further comprising:

a power source connected to the mounting rings;

a controller that controls the power source; and

a switch connected to the controller, the switch having a first position at which the controller applies different polarities to the first and third mounting rings, and a second position at which the controller applies the same polarity to the first and third mounting rings.

37. The apparatus of claim 28 further comprising a guide wire lumen configured to accept a guide wire.

38. The apparatus of claim 37 wherein the guide wire lumen is capable of being connected to a fluid delivery system.

39. The apparatus of claim 28 wherein the blunt distal ends of the arms are rounded.

40. The apparatus of claim 39 wherein the electrodes are located at the blunt distal ends of the arms and the electrodes have an approximate hemispherical shape.

41. Apparatus for applying energy to a hollow anatomical structure comprising;

a catheter having a shaft with a working end;

a first plurality of expandable arms mounted to the working end of the catheter at a first location, each expandable arm having an energy application portion configured to apply energy to the hollow anatomical structure; and

a second plurality of expandable arms mounted to the working end of the catheter at a second location that is separate from and longitudinally spaced apart from the first location at which the first plurality of expandable arms is mounted, the second plurality being configured to expand independently from the first plurality, each expandable arm of the second plurality having an energy application portion configured to apply energy to the hollow anatomical structure;

wherein the arms of the first and second pluralities each have an expanded position at which the energy application portions are located outward from the catheter shaft;

wherein each expandable arm has a blunt distal end;

wherein the arms are formed to have sufficient force to move into apposition with the hollow anatomical structure, and the formed arms do not have sufficient strength to prevent the reduction of the diameter of the hollow anatomical structure when energy is applied by the energy application portion of the arms.

42. The apparatus of claim 41 wherein the energy application portions of the first and second pluralities of expandable arms are configured to be selectively energized.

43. The apparatus of claim 41 wherein the energy application portions of the first and second pluralities of expandable arms are configured to be energized such that the energy will flow between selected energy application portions of the same plurality.

44. The apparatus of claim 41 wherein the energy application portions of the first and second pluralities of expandable arms are configured to be energized such that the energy will flow between selected energy application portions of the first plurality and selected energy application portions of the second plurality.

45. The apparatus of claim 44 wherein the arms of the first and second pluralities of expandable arms are configured to apply energy along an axial length of the hollow anatomical structure.

46. The apparatus of claim 44 wherein each energy application portion comprises an electrode for applying electrical energy to the hollow anatomical structure, the electrode being configured so that the catheter and electrodes may be moved while remaining in non-penetrating contact with the hollow anatomical structure during the application of energy.

47. The apparatus of claim 44 wherein each of the arms of the first and second pluralities is formed with an outward bend that tends to expand the distal portion of each arm outwardly into non-penetrating contact with the hollow anatomical structure.

48. The apparatus of claim 44 wherein the arms are mounted at the working end in a cantilever arrangement.

49. The apparatus of claim 44 wherein each of the arms of the first and second pluralities are disposed in relation to the working end such that when in the expanded position, the arms form a substantially symmetric arrangement of substantially evenly spaced arms.

50. The apparatus of claim 44 further comprising a fluid delivery lumen between the catheter shaft and the movable sheath.

51. The apparatus of claim 44 wherein the energy application portions are located at the blunt distal ends of the arms and the energy application portions have an approximate hemispherical shape.

52. The apparatus of claim 44 wherein the arms are configured such that when in the expanded position, they form an acute angle with the catheter shaft.

53. The apparatus of claim 44 wherein the expandable arms are configured so as to permit the catheter to be moved in the hollow anatomical structure at the same time that the energy application portions of the arms are applying energy to the hollow anatomical structure.

54. The apparatus of claim 53 wherein the energy application portions of the arms are rounded such that the arms may be moved with the catheter while remaining in non-penetrating contact with the hollow anatomical structure.

55. The apparatus of claim 44 further comprising a guide wire lumen configured to accept a guide wire.

56. The apparatus of claim 55 wherein the guide wire lumen is capable of delivering fluid to the hollow anatomical structure.

57. Apparatus for applying energy to structurally transfigure collagen fibrils of a hollow anatomical structure, comprising:

a catheter having a shaft with a working end at which energy is applied to the hollow anatomical structure;

means for applying energy to the hollow anatomical structure, wherein the collagen fibrils of the tissue of the hollow anatomical structure become heated and transfigured such that the hollow anatomical structure collapses and effectively occludes the hollow anatomical structure;

wherein the means for applying energy further includes;

a first plurality of expandable arms, each arm of the first plurality being mounted to the working end of the catheter at a first location, and with each arm being configured to expand outwardly from the catheter shaft, each arm having an energy application portion located on the respective arm;

a second plurality of expandable arms, each arm of the second plurality being mounted to the working end of the catheter at a second location that is separate from and longitudinally spaced apart from the first location at which the first plurality is mounted, and with the arms of the second plurality being configured to expand outwardly from the catheter shaft independently from the first plurality of arms, each arm having an energy application portion located on the respective arm;

wherein each arm has a blunt distal end;

wherein the two separate sets of expandable arms do not have sufficient strength to prevent the reduction of the diameter of the hollow anatomical structure when energy is applied by the means for applying energy.

58. The apparatus of claim 57 wherein the arms and energy application portions are shaped such that the catheter can be moved in the hollow anatomical structure at the same time that the energy application portions are applying energy to the hollow anatomical structure.

59. The apparatus of claim 57 wherein the arms are capable of being expanded to come into apposition with the lumen of the hollow anatomical structure.

60. The apparatus of claim 57 further comprising means for delivering a fluid for exsanguinating the hollow anatomical structure.

61. The apparatus of claim 57 wherein the arms are configured such that when in the expanded position, they form an acute angle with the catheter shaft.

62. The apparatus of claim 57 wherein the blunt distal ends of the arms are rounded.

63. The apparatus of claim 62 wherein the electrodes are located at the blunt distal ends of the arms and the electrodes have an approximate hemispherical shape.