Self-expanding cooling electrode for renal nerve ablation

• US 9,848,946 B2
• Filed: 05/11/2015
• Issued: 12/26/2017
• Est. Priority Date: 11/15/2010
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Inventors: Edmunds, Kevin D., Jenson, Mark L.
• Primary Examiner(s): EVANISKO, GEORGE ROBERT
• Application Number:
  US14/709,019
• Publication Number:
  US 20150238249A1
• Time in Patent Office: 960 Days
• CPC Class Codes: A61B 18/1482 having a long rigid shaft for accessing the inner body transcutaneously in minimal invasive surgery, e.g. laparoscopy
• 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 2018/00023 closed, i.e. without wound contact by the fluid
• CPC Class Codes: A61B 2018/00029 open
• CPC Class Codes: A61B 2018/00214 Expandable means emitting energy, e.g. by elements carried thereon
• CPC Class Codes: A61B 2018/00404 Blood vessels other than those in or around the heart
• CPC Class Codes: A61B 2018/00434 Neural system
• CPC Class Codes: A61B 2018/00505 Urinary tract
• CPC Class Codes: A61B 2018/00511 Kidney
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/0072 Current
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/1435 Spiral

Abstract

A metallic tube arrangement includes an electrode region configured to expand radially and contract radially in response to increasing and decreasing a temperature at the electrode region, respectively. The electrode region is configured for intravascular deployment and delivery of high frequency energy to target tissue of a target vessel of the body. The electrode region is configured to expand radially to a diameter sufficient to contact an inner wall of the target vessel in response to a decrease in electrode region temperature and to contract radially to a diameter smaller than a diameter of the target vessel in response to an increase in electrode region temperature.

Claims

1. An apparatus, comprising:

a tube arrangement comprising a proximal end region, a distal end region, an inlet, and an outlet, the distal end region comprising a coil section and the proximal end region comprising the inlet adapted to receive cooled thermal transfer fluid;

the coil section having a reduced profile delivery configuration, and an expanded treatment configuration, and comprising a metallic material, a reduced temperature of the metallic material when contacted by the cooled thermal transfer fluid causing the coil section to transition from the reduced profile delivery configuration to the expanded treatment configuration; and

at least a portion of the coil section defining an electrode configured to deliver high frequency energy to target tissue.

2. The apparatus of claim 1, wherein the reduced profile delivery configuration has a first outer diameter and the expanded treatment configuration has a second outer diameter, the second outer diameter greater than the first outer diameter.

3. The apparatus of claim 1, wherein the coil section is configured to contract radially in response to removal of the cooled thermal transfer fluid via the outlet.

4. The apparatus of claim 1, wherein the proximal end region of the tube arrangement is configured to be electrically coupled to an electrical energy generator.

5. The apparatus of claim 1, wherein:

the coil section is configured to deliver the high frequency energy to the target tissue sufficient to ablate the target tissue; and

the coil section is configured to receive the cooled thermal transfer fluid at a temperature that provides protective cooling to tissue adjacent to the target tissue and that causes radial expansion of the coil section.

6. The apparatus of claim 1, wherein:

the outlet of the tube arrangement is adapted to expel received cooled thermal transfer fluid into blood flowing through a target vessel.

7. The apparatus of claim 1, wherein the coil section is formed of a single layer of a memory alloy.

8. The apparatus of claim 1, wherein the coil section defines a two-sided bimetallic structure.

9. The apparatus of claim 1, wherein the coil section is wrapped around a portion of itself.

10. The apparatus of claim 1, wherein the inlet and the outlet are both accessible from the proximal end region of the tube arrangement.

11. An apparatus, comprising:

a tube arrangement comprising a proximal end region, a distal end region, an inlet, and an outlet, the distal end region comprising a metallic coil section;

the metallic coil section having a delivery configuration and a treatment configuration, the treatment configuration configured to contact an inner wall of a target vessel;

at least a portion of the metallic coil section defining an electrode configured to deliver high frequency energy to target tissue;

a cooled thermal transfer fluid source coupled to the inlet of the tube arrangement to provide a cooled thermal transfer fluid to the tube arrangement;

wherein the metallic coil section is configured to radially expand from the delivery configuration to the treatment configuration, a reduced temperature of a metallic material of the metallic coil section when the metallic coil section is contacted by the cooled thermal transfer fluid causing transition from the delivery configuration to the expanded treatment configuration.

12. The apparatus of claim 11, wherein the proximal end region of the tube arrangement comprises a first material and the metallic coil section comprises a second material different from the first material.

13. The apparatus of claim 11, wherein the delivery configuration has a first outer diameter and the treatment configuration has a second outer diameter, the second outer diameter greater than the first outer diameter.

14. The apparatus of claim 11, wherein the metallic coil section is configured to contract radially in response to removal of the cooled thermal transfer fluid via the outlet.

15. The apparatus of claim 11, wherein the metallic coil section comprises one or more insulated sections and one or more exposed sections, the one or more exposed sections defining one or more electrodes.

16. The apparatus of claim 11, wherein the metallic coil section comprises a material having a negative thermal coefficient of expansion.

17. An apparatus, comprising:

a tube arrangement comprising a proximal end region, a distal end region, an inlet, and an outlet, the distal end region comprising a coil section formed from a material having a negative thermal coefficient of expansion, and the proximal end region comprising the inlet adapted to receive cooled thermal transfer fluid;

the coil section having a reduced profile delivery configuration and an expanded treatment configuration, a reduced temperature of the material when contacted by the cooled thermal transfer fluid causing the coil section to transition from the reduced profile delivery configuration to the expanded treatment configuration; and

at least a portion of the coil section defining an electrode configured to deliver high frequency energy to target tissue sufficient to ablate a target tissue; and

wherein the coil section is configured to receive the cooled thermal transfer fluid at a temperature that provides protective cooling to tissue adjacent to the target tissue.