Method for R-F ablation

• US 5,609,151 A
• Filed: 09/08/1994
• Issued: 03/11/1997
• 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:
  US08/303,246
• Time in Patent Office: 915 Days
• Field of Search: 606/41, 606/27, 128/642, 607/122, 607/127, 607/105, 607/113, 607/99
• US Class Current: 600/373
• 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 open to the distal end of said catheter body to a desired tissue location;

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

cooling said fluid while in said internal lumen; and

monitoring the response of said tissue to said cooled fluid.

2. A method according to claim 1, wherein;

said advancing step comprises advancing a catheter provided with a hollow needle coupled to the distal end of said internal lumen to said desired tissue location and penetrating tissue with said needle; and

wherein said delivering step comprises delivering said fluid into said tissue through said needle.

3. A method according to claim 2, wherein;

said advancing step comprises advancing a catheter provided with a hollow helical needle coupled to the distal end of said internal lumen to said desired tissue location and screwing said helical needle into said tissue.

4. A method of ablating tissue, comprising:

advancing an elongated catheter including a catheter body having proximal and distal ends and having an internal longitudinal lumen and a hollow conductive electrode mounted to the distal end of said catheter body and having an internal lumen coupled to the internal lumen of said catheter body to a desired tissue location;

delivering a conductive fluid to said internal lumen of said catheter body and to said desired tissue location through said internal lumen of said electrode;

heating said fluid while in said internal lumen of said catheter body; and

delivering R-F energy to said electrode.

5. A method according to claim 4, wherein;

said advancing step comprises advancing a catheter provided with a hollow needle coupled to the distal end of said internal lumen of said catheter body to said desired tissue location and penetrating tissue with said needle; and

wherein said delivering step comprises delivering said fluid into said tissue through said needle.

6. A method according to claim 5, wherein;

said advancing step comprises advancing a catheter provided with a hollow helical needle coupled to the distal end of said internal lumen of said catheter body to said desired tissue location and screwing said helical needle into said tissue.

7. A method of ablating tissue comprising:

advancing an elongated catheter including a catheter body having proximal and distal ends and having an internal longitudinal lumen and a hollow member mounted to the distal end of said catheter body and having an internal lumen coupled to the internal lumen of said catheter body to a desired location and inserting said hollow member into tissue;

delivering a fluid to said internal lumen of said catheter body and to said desired location through said hollow member; and

heating said fluid while in said internal lumen of said catheter body.