Method for R-F ablation

• US 5,906,613 A
• Filed: 12/03/1997
• Issued: 05/25/1999
• Est. Priority Date: 09/08/1994
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Hoey, Michael F., Mulier, Peter M. J.
• Primary Examiner(s): COHEN, LEE S
• Application Number:
  US08/984,385
• Time in Patent Office: 538 Days
• Field of Search: 606/41, 606/27, 600/374, 607/99, 607/105, 607/113, 607/122, 607/127
• US Class Current: 606/41
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 18/1477 Needle-like probes
• 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 2017/00292 mounted on or guided by flexible, e.g. catheter-like, means
• CPC Class Codes: A61B 2018/00011 with fluids
• 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 2018/00035 with return means
• CPC Class Codes: A61B 2018/00041 Heating, e.g. defrosting
• CPC Class Codes: A61B 2018/00065 porous
• CPC Class Codes: A61B 2018/00077 high, i.e. electrically conducting
• CPC Class Codes: A61B 2018/1253 monopolar
• CPC Class Codes: A61B 2018/126 bipolar
• CPC Class Codes: A61B 2018/1425 Needle
• CPC Class Codes: A61B 2018/1435 Spiral
• CPC Class Codes: A61B 2018/1472 for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2018/162 located on the probe body
• CPC Class Codes: A61B 2218/002 Irrigation

Abstract

A method and apparatus for ablation of body tissue. A catheter provided with a hollow needle is employed both for mapping the location to be ablated by injection of an excitability reducing agent and for ablating tissue, employing RF energy in conjunction with an injected, conductive fluid.

Claims

1. A method of mapping cardiac tissue, comprising:

advancing an elongated catheter including a catheter body having proximal and distal ends comprising a first tube having an internal longitudinal lumen and a hollow needle having a laterally opening aperture coupled to the distal end of said internal lumen to a desired tissue location and inserting said needle into said tissue;

delivering fluid to said internal lumen and to said desired tissue location through said aperture;

cooling said fluid while in said internal lumen;

monitoring the response of said tissue to said cooled fluid;

rotating said hollow needle; and

repeating said delivering and monitoring steps.

2. A method according to claim 1 wherein said advancing step comprises advancing an elongated catheter having a hollow helical needle having a laterally opening aperture and wherein said rotating step comprises screwing said helical needle into said tissue.

3. A method of mapping and ablating cardiac tissue, comprising:

advancing an elongated catheter including a catheter body having proximal and distal ends comprising a first tube having an internal longitudinal lumen and a hollow needle having a laterally opening aperture coupled to the distal end of said internal lumen to a desired tissue location and inserting said needle into said tissue;

delivering fluid to said internal lumen and to said desired tissue location through said aperture;

cooling said fluid while in said internal lumen;

monitoring the response of said tissue to said cooled fluid;

rotating said hollow needle to a different position;

repeating said delivering and monitoring steps until a desired response of said tissue is obtained;

while said needle is in the position in which said desired response is obtained, applying electrical energy to said tissue via said needle.

4. A method according to claim 3, wherein said applying electrical energy step comprises delivery of a conductive fluid through said aperture.

5. A method according to claim 3 wherein said fluid delivering step comprises delivery of a conductive fluid through said aperture.

6. A method according to claim 3 or claim 4 or claim 5 wherein said advancing step comprises advancing an elongated catheter having a hollow helical needle having a laterally opening aperture and wherein said rotating step comprises screwing said helical needle into said tissue.

7. A method of mapping tissue, comprising:

advancing an elongated catheter including a catheter body having proximal and distal ends comprising a first tube having an internal longitudinal lumen and a hollow needle having a laterally opening aperture coupled to the distal end of said internal lumen to a desired tissue location and inserting said needle into said tissue;

cooling a fluid;

delivering said cooled fluid to said desired tissue location through said aperture;

monitoring the response of said tissue to said cooled fluid;

rotating said hollow needle; and

repeating said delivering and monitoring steps.

8. A method according to claim 7 wherein said advancing step comprises advancing an elongated catheter having a hollow helical needle having a laterally opening aperture and wherein said rotating step comprises screwing said helical needle into said tissue.

9. A method of mapping and ablating tissue, comprising:

advancing an elongated catheter including a catheter body having proximal and distal ends comprising a first tube having an internal longitudinal lumen and a hollow needle having a laterally opening aperture coupled to the distal end of said internal lumen to a desired tissue location and inserting said needle into said tissue;

cooling a fluid;

delivering said cooled fluid to said desired tissue location through said aperture;

monitoring the response of said tissue to said cooled fluid;

rotating said hollow needle to a different position;

repeating said delivering and monitoring steps until a desired response of said tissue is obtained;

while said needle is in the position in which said desired response is obtained, applying electrical energy to said tissue via said needle.

10. A method according to claim 9, wherein said applying electrical energy step comprises delivery of a conductive fluid through said aperture.

11. A method according to claim 9 wherein said fluid delivering step comprises delivery of a conductive fluid through said aperture.

12. A method according to claim 9 or claim 10 or claim 11 wherein said advancing step comprises advancing an elongated catheter having a hollow helical needle having a laterally opening aperture and wherein said rotating step comprises screwing said helical needle into said tissue.