Renal denervation catheter with cooled RF electrode

• US 9,192,435 B2
• Filed: 11/22/2011
• Issued: 11/24/2015
• Est. Priority Date: 11/22/2010
• Status: Expired due to Fees

• Current Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed, Inc. (Boston Scientific Corporation)
• Inventors: Jenson, Mark L.
• Primary Examiner(s): Layno, Carl H
• Assistant Examiner(s): PIATESKI, ERIN M
• Application Number:
  US13/302,651
• Publication Number:
  US 20120130368A1
• Time in Patent Office: 1,463 Days
• Field of Search: 606/41
• US Class Current: 1/1
• 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 2018/00029 open
• CPC Class Codes: A61B 2018/00083 low, i.e. electrically insulating
• CPC Class Codes: A61B 2018/0016 Energy applicators arranged in a two- or three dimensional array
• CPC Class Codes: A61B 2018/00214 Expandable means emitting energy, e.g. by elements carried thereon
• CPC Class Codes: A61B 2018/00279 deployable
• 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 2018/00511 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 2018/00648 using more than one sensed parameter
• CPC Class Codes: A61B 2018/00654 with individual control of each of a plurality of energy emitting elements
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00791 Temperature
• CPC Class Codes: A61B 2018/00875 Resistance or impedance
• CPC Class Codes: A61B 2018/1497 Electrodes covering only part of the probe circumference

Abstract

A catheter has a flexible shaft with a proximal end, a distal end, a lumen arrangement, and a length sufficient to access a patient'"'"'s renal artery. A conductor arrangement extends between the proximal and distal ends of the shaft. An actuatable helical tip region is provided at the distal end of the shaft, and a bend region is located proximal of the actuatable helical tip region. An electrode arrangement is provided at the actuatable helical tip region and dimensioned for deployment within the target vessel, such as the renal artery. The electrode arrangement is coupled to the conductor arrangement and includes a multiplicity of electrodes positioned on the distal end of the shaft in a spaced relationship. The electrodes have a protruding portion that extends out a distance beyond an outer surface of the distal end of the shaft.

Claims

1. An apparatus, comprising:

a catheter comprising a flexible shaft having a proximal end, a distal end, a lumen arrangement comprising a coolant lumen extending between the proximal and distal ends, and

a length sufficient to access a patient'"'"'s renal artery relative to a percutaneous access location;

a conductor arrangement extending between the proximal and distal ends of the shaft; and

an electrode arrangement coupled to the conductor arrangement and provided at the distal end of the shaft, the electrode arrangement dimensioned for deployment within the renal artery and comprising;

a plurality of electrodes positioned on the distal end of the shaft in a spaced relationship, each of the electrodes comprising;

a protuberance that extends out a distance beyond an outer surface of the distal end of the shaft, the protuberance defining a tissue contacting surface and an opposing blood contacting surface, wherein the coolant lumen comprises a continuous tube that passes through a channel in the protuberance;

wherein the electrodes have a substantially spherical shape and a diameter greater than that of the distal end of the shaft;

wherein the electrode arrangement comprises;

electrically insulating material disposed between adjacent electrodes to electrically isolate the electrodes from one another; and

electrically insulating material disposed on an outer the blood contacting surface of each of the electrodes protuberances configured to face away from a wall of the renal artery and an integral cooling arrangement fluidly coupled to the coolant lumen of the lumen arrangement, the coolant lumen and integral cooling arrangement configured to receive a biocompatible thermal transfer fluid;

and wherein at least one of the integral cooling arrangement and the distal end of the coolant lumen is configured to expel spent thermal transfer fluid into a blood stream of the renal artery.

2. The apparatus of claim 1, wherein each of the electrodes is electrically coupled to one of a plurality of conductors of the conductor arrangement, allowing each of the electrodes to be individually activated and deactivated.

3. The apparatus of claim 1, wherein the integral cooling arrangement of each of the electrodes comprises an inner tube segment configured to enhance securing of one of the plurality of electrodes to the distal end of the shaft.

4. The apparatus of claim 1, wherein each of the electrodes comprises apertures through which at least some of the thermal transfer fluid can pass into the blood stream of the renal artery.

5. The apparatus of claim 1, further comprising a stiffening member provided at the distal end of the shaft that includes the electrodes, the stiffening member serving to strengthen and limit the curvature of the distal end of the shaft.

6. The apparatus of claim 5, wherein the stiffening member comprises one of a shape memory material, a shape memory material having a generally spiral pre-formed shape, and a flat shape memory material having a generally spiral pre-formed shape.

7. The apparatus of claim 1, wherein the lumen arrangement comprises a lumen dimensioned to receive an elongated shaping member configured to impart and alter a shape of the shaft'"'"'s distal end.

8. The apparatus of claim 1, comprising an external sheath having a lumen dimensioned for placement within the renal artery and to receive the catheter with the electrode arrangement in a substantially flattened configuration.