Electrosurgical device for creating a channel through a region of tissue and methods of use thereof

• US 20110118735A1
• Filed: 11/08/2010
• Published: 05/19/2011
• Est. Priority Date: 01/21/2003
• Status: Active Grant

• Current Assignee: Boston Scientific Medical Device Limited (Boston Scientific Corporation)
• Original Assignee: Baylis Medical Company
• Inventors: Abou-Marie, Rund, Leung, Ramsey, Albert, Kelly, Mosley, Mark, Juzkiw, Taras, Luk, Maria, Wong, Christine, Davies, Gareth
• Granted Patent: US 9,510,900 B2
• Time in Patent Office: Days
• US Class Current: 606/45
• 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 2017/00867 shape memory effect for prostheses A61F2210/0014
• CPC Class Codes: A61B 2018/00083 low, i.e. electrically insulating
• CPC Class Codes: A61B 2018/00101 low, i.e. thermally insulating
• CPC Class Codes: A61B 2018/00136 with polymer
• CPC Class Codes: A61B 2018/0041 Removal of thrombosis
• CPC Class Codes: A61B 2018/1213 creating an arc
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: C08L 2201/12 Shape memory

Abstract

An electrosurgical device and methods are disclosed for creating a channel through a region of tissue. The device comprises an elongate member for receiving the energy from an electrical energy source. An electrical insulation layer surrounds the elongate member along the device proximal region. An electrode tip is coupled to the distal end of the elongate member for delivering the energy, the electrode tip being configured and sized for delivering the energy in a manner such that electrical arcing is generated in the region of tissue in order to create a channel through at least a portion of the region of tissue. An electrically insulative thermal shield is disposed between the electrode tip and the device proximal region for preventing arcing therebetween during the delivery of the energy and for thermally protecting the device proximal region from heat produced by the delivery of the energy through the electrode tip.

Claims

1. An electrosurgical device for creating a channel through a region of tissue using energy provided by an electrical energy source, the device defining a device proximal region and a device distal region, the device comprising:

an electrically conductive elongate member for receiving the energy from the electrical energy source, the elongate member defining a distal end provided in the device distal region;

an electrical insulation layer surrounding the elongate member along the device proximal region;

an electrode tip electrically coupled to the distal end for delivering the energy, the electrode tip being configured and sized for delivering the energy in a manner such that electrical arcing is generated in the region of tissue in order to create a channel through at least a portion of the region of tissue when the electrode tip is positioned proximate the region of tissue; and

an electrically insulative thermal shield disposed between the electrode tip and the device proximal region for preventing arcing therebetween during the delivery of the energy and for thermally protecting the device proximal region from heat produced by the delivery of the energy through the electrode tip.

2. The electrosurgical device of claim 1, wherein the thermal shield has a thermal conductivity of about 1 W/m-K or more.

3. The electrosurgical device of claim 2, wherein the thermal shield has a thermal conductivity of about 2 W/m-K or more.

4. The electrosurgical device of claim 1, wherein the electrode tip is configured and sized for generating a current density sufficient for initiating arcing at the electrode tip during the delivery of the energy, thereby allowing the device to create the channel through the at least a portion of the region of tissue.

5. The electrosurgical device of claim 4, wherein the electrode tip is shaped substantially like a segment of a sphere.

6. The electrosurgical device of claim 1, wherein the elongate member comprises a shape memory alloy.

7. The electrosurgical device of claim 6, wherein the elongate member comprises a nickel-titanium alloy.

8. The electrosurgical device of claim 3, wherein the thermal shield comprises single crystal aluminum oxide.

9. The electrosurgical device of claim 1, further comprising a radiopaque band positioned proximally with respect to the thermal shield.

10. The electrosurgical device of claim 9, wherein the radiopaque band is operatively coupled to the elongate member adjacent the thermal shield to support the thermal shield on the elongate member.

11. The electrosurgical device of claim 1, wherein the electrode tip is formed integrally with the elongate member.

12. The electrosurgical device of claim 11, wherein the elongate member and electrode tip both comprise a shape memory nickel-titanium alloy.

13. The electrosurgical device of claim 1, further comprising a support structure positioned distally with respect to the thermal shield for supporting the electrode tip.

14. The electrosurgical device of claim 13, wherein the support structure is electrically conductive.

15. The electrosurgical device of claim 14, wherein the support structure comprises tantalum.

16. The electrosurgical device of claim 13, wherein the electrode tip is attached to the support structure.

17. The electrosurgical device of claim 16, wherein the electrode tip is laser welded to the support structure.

18. The electrosurgical device of claim 17, wherein the electrode tip comprises a shape memory nickel titanium alloy.

19. The electrosurgical device of claim 18, wherein the electrode tip is formed by laser welding the distal end onto the support structure.

20. The electrosurgical device of claim 19, wherein the support structure comprises tantalum.

21. The electrosurgical device of claim 1, wherein the electrode tip and the thermal shield define respectively a tip outer diameter and a shield outer diameter, the tip outer diameter being greater than or equal to the shield outer diameter.

22. The electrosurgical device of claim 21, wherein the tip outer diameter is greater than the shield outer diameter.

23. The electrosurgical device of claim 1, wherein the device proximal region defines a proximal region maximal diameter and the electrode tip defines a tip diameter, the proximal region maximal diameter being greater than the tip diameter.

24. The electrosurgical device of claim 1, wherein the electrical insulation layer overlaps a portion of the thermal shield.

25. The electrosurgical device of claim 1, wherein the thermal shield is radiopaque.

26. The electrosurgical device of claim 13, wherein the support structure is radiopaque.

27. The electrosurgical device of claim 1, wherein a portion of the electrosurgical device is coated with a hydrophilic coating.

28. The electrosurgical device of claim 6, wherein the elongate member is shape-set to a preset curvature.

29. The electrosurgical device of claim 1, wherein the electrosurgical device has a predefined curvature.

30. A method for creating a channel through an occlusion located in a body vessel of a patient, the occlusion including an occlusion harder portion and an occlusion softer portion, the method using a channel creating apparatus defining an apparatus distal end portion insertable into the body vessel, the channel creating apparatus including an energy delivery component operatively coupled to the apparatus distal end portion for delivering energy proximate the apparatus distal end portion, the method comprising:

positioning the apparatus distal end portion substantially adjacent the occlusion;

creating a harder portion channel through the occlusion harder portion, by delivering energy into the occlusion harder portion using the energy delivery component; and

creating a softer portion channel through the occlusion softer portion by advancing the apparatus distal end portion through at least a portion of the occlusion softer portion substantially without using the energy delivery component to deliver energy into the occlusion softer portion.

31. The method of claim 30, further comprising the step of initiating arcing at the energy delivery component during the step of delivering energy into the occlusion harder portion to create the harder portion channel.

32. The method of claim 30, wherein the step of creating the softer portion channel is performed before the step of creating the harder portion channel.

33. A method for creating a channel through an occlusion located in a body vessel of a patient, the method using a channel creating apparatus defining an apparatus distal end portion insertable into the body vessel, the channel creating apparatus including an energy delivery component operatively coupled to the apparatus distal end portion for delivering energy proximate the apparatus distal end portion, the method comprising the steps of:

(i) positioning the apparatus distal end portion substantially adjacent the occlusion;

(ii) testing the occlusion to determine whether the apparatus distal end portion can be advanced through the occlusion (A) by the application of mechanical force or (B) by delivering energy into the occlusion using the energy delivery component;

(iii) creating a channel portion through at least a portion of the occlusion by (A) or (B) as determined in step (ii).