Heart wall ablation/mapping catheter and method

• US 8,706,260 B2
• Filed: 10/27/2011
• Issued: 04/22/2014
• Est. Priority Date: 10/10/2000
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Stewart, Mark T., Goode, Johnson E.
• Primary Examiner(s): Koharski, Christopher D
• Assistant Examiner(s): Dinga, Roland
• Application Number:
  US13/282,997
• Publication Number:
  US 20120078076A1
• Time in Patent Office: 908 Days
• Field of Search: 604 9501- 9505, 607/122, 606/41, 600/433, 600/366
• US Class Current: 607/122
• 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 2017/00243 cardiac
• CPC Class Codes: A61B 2018/00916 with means for switching or controlling the main function of the instrument or device
• CPC Class Codes: A61M 2025/015 Details of the distal fixation of the movable mechanical means
• CPC Class Codes: A61M 2025/0161 wherein the distal tips have two or more deflection regions
• CPC Class Codes: A61M 25/0147 with movable mechanical means, e.g. pull wires
• CPC Class Codes: A61M 25/0152 with pre-shaped mechanisms, e.g. pre-shaped stylets or pre-shaped outer tubes

Abstract

A catheter suitable for use in applying ablation energy to body tissue or detecting electrical signals conducted within the body tissue is disclosed. The catheter has a deflectable distal tip section. At least one electrode is adapted to be disposed against body tissue for delivery of ablation energy thereto or for conduction of body tissue electrical signals. An actuation mechanism comprising first and second pull wires is adapted to curve a proximal segment in a first direction and to independently bend an intermediate segment in a second direction.

Claims

1. A catheter suitable for use in applying ablation energy to body tissue or detecting electrical signals conducted within the body tissue comprising:

an elongated catheter body with a smooth outer surface, said elongated catheter body having a catheter body axis and extending between a catheter body proximal end and a catheter body distal end, the elongated catheter body having a catheter body proximal section extending distally from said catheter body proximal end and a deflectable distal tip section extending proximally from said catheter body distal end to a junction with said catheter body proximal section;

said deflectable distal tip section including a distal segment, a curvable proximal segment having a proximal segment length and a bendable intermediate segment having an intermediate segment length disposed between the distal segment and the curvable proximal segment;

at least one electrode positioned along the distal segment that is adapted to be disposed against body tissue for delivery of ablation energy thereto or for conduction of body tissue electrical signals;

a handle at the proximal end of the catheter body, said handle having a proximal handle end and a distal handle end, said handle having a stop plate within said handle distal end;

a conductor extending through the catheter body from the handle to the electrode; and

an actuation mechanism extending through the catheter body to the deflectable tip section to selectively deflect the catheter body axis in the deflectable distal tip section with respect to the catheter body axis in the catheter body proximal section, the actuation mechanism adapted to curve the proximal segment in a first direction and to bend the intermediate segment in a second direction independently of the curve of the proximal segment to dispose the distal segment at a desired orientation to body tissue, wherein the actuation mechanism further comprises;

a first pull wire extending between a first pull wire proximal end disposed within said handle and a first pull wire distal end coupled to said distal segment;

a first pull wire lumen formed within said catheter body and extending between a first pull wire lumen proximal end communicating with said handle and a first pull wire lumen distal end, said first pull wire enclosed within said first pull wire lumen, said first pull wire lumen extending in parallel with said catheter body axis and displaced therefrom at a first off-axis location through said proximal and intermediate segments, and said first pull wire distal end affixed to said distal segment;

a first pull wire control formed in said handle coupled with said first pull wire proximal end enabling application and release of tension on said first pull wire, said first pull wire control having an extended position wherein said first pull wire is slack and a plurality of retracted positions wherein said first pull wire is retracted and tensioned thereby imparting a knuckle curvature through the intermediate segment length with respect to said proximal segment and deflecting the catheter body axis of said distal segment with respect to the catheter body axis of the catheter body in the catheter body proximal section and the proximal segment;

a second pull wire extending between a second pull wire proximal end disposed within said handle and a second pull wire distal end coupled to the junction of said intermediate segment with said proximal segment;

a second pull wire lumen formed within said catheter body and extending between a second pull wire lumen proximal end communicating with said handle and a second pull wire lumen distal end, said second pull wire enclosed within said second pull wire lumen, said second pull wire lumen extending in parallel with said catheter body axis and displaced therefrom at a second off-axis location through said proximal segment, and said second pull wire distal end affixed to a junction of said proximal and intermediate segments, said first and second off-axis locations aligned with a common radial direction extending away from the catheter body axis;

a second pull wire control formed in said handle coupled with said second pull wire proximal end enabling application and release of tension on said second pull wire independently of application and release of tension on said first pull wire, said second pull wire control having an extended position wherein said second pull wire is slack and a plurality of retracted positions wherein said second pull wire is retracted and tensioned thereby imparting a curvature through the proximal segment length with respect to said distal segment and deflecting the catheter body axis of said proximal segment with respect to the catheter body axis of catheter body in the catheter body proximal section and the distal segment,

whereby independent manipulation of the first and second pull wire controls enables a knuckle curvature of the intermediate segment that deflects the distal segment in a first direction with respect to the proximal segment and formation of a curve in the proximal segment in a second direction sharing a common plane with respect to the catheter body axis in the catheter body proximal section and in the distal segment.

2. The catheter of claim 1, further comprising:

a first incompressible wire coil having a first wire coil lumen and extending between a first coil proximal end, said first coil proximal end proximate but not attached to said handle, and a first coil distal end and having a first coil lumen and first coil diameter, said first incompressible coil disposed within said first pull wire lumen with said first coil distal end disposed proximally to said intermediate tip section, and said first pull wire extending through said first incompressible coil lumen, whereby a distal portion of said first pull wire extends distally from said first coil distal end through said intermediate tip section; and

a second incompressible wire coil having a second wire coil lumen and extending between a second coil proximal end, said second coil proximal end proximate but not attached to said handle and a second coil distal end and having a second coil lumen and second coil diameter, said second incompressible coil disposed within said second pull wire lumen with said second coil distal end disposed proximally to said proximal tip section, and said second pull wire extending through said second incompressible coil lumen, whereby a distal portion of said second pull wire extends distally from said second coil distal end through said proximal tip section to a junction with said intermediate tip section.

3. The catheter of claim 2, wherein the intermediate segment capable of bending in a knuckle bend having a radius of between about 2.0 mm and 7.0 mm through a range of about −

90°

to +180°

with respect to the catheter body axis at the intermediate segment proximal end.

4. The catheter of claim 3, wherein the curve induced in the proximal segment is in the range of about −

180°

to about +270°

with respect to the catheter body axis at the junction of the proximal section with the proximal segment.

5. A catheter comprising:

a catheter body including a center longitudinal axis and a distal tip, the distal tip having a proximal segment, an intermediate segment, and a distal segment;

a handle at the proximal end of the catheter body, said handle having a proximal handle end and a distal handle end, said handle having a stop plate within said handle distal end;

a first pull wire having a proximal end, a distal end, and a longitudinal axis, the first pull wire forming a first curve having a first radius of curvature in the intermediate segment of the catheter distal tip when the first pull wire moves along the first pull wire longitudinal axis; and

a second pull wire having a proximal end, a distal end, and a longitudinal axis, the second pull wire forming a second curve having a second radius of curvature in the proximal segment of the catheter distal tip when the second pull wire moves along the second pull wire longitudinal axis;

a first incompressible wire coil having a first wire coil lumen and extending between a first coil proximal end, said first coil proximal end proximate but not attached to said stop plate, and a first coil distal end and having a first coil lumen and first coil diameter, said first pull wire extending through said first incompressible coil lumen, whereby a distal portion of said first pull wire extends distally from said first coil distal end through said intermediate tip section; and

a second incompressible wire coil having a second wire coil lumen and extending between a second coil proximal end, said second coil proximal end proximate but not attached to said stop plate and a second coil distal end and having a second coil lumen and second coil diameter, said second pull wire extending through said second incompressible coil lumen, whereby a distal portion of said second pull wire extends distally from said second coil distal end through said proximal tip section to a junction with said intermediate tip section.

6. The catheter of claim 5, wherein the first radius of curvature is greater than the second degree of curvature.

7. The catheter of claim 5, wherein the second radius of curvature is greater than the first degree of curvature.

8. The catheter of claim 5 wherein the catheter body longitudinal axis is at 0°

, and the distal tip is deflected at the intermediate segment to between approximately −

90° and

approximately 180°

from the catheter body center longitudinal axis.

9. The catheter of claim 8, wherein the distal tip is deflected at the proximal segment to between approximately −

90° and

approximately 270°

from the catheter body center longitudinal axis.

10. The catheter of claim 9, wherein the first pull wire and second pull wire are each positioned parallel to the catheter body center longitudinal axis, the first pull wire being at a first off-center location and the second pull wire being at a second off-center location, the first and second off-center locations being in a common radial direction from the center longitudinal axis.

11. The catheter of claim 9, wherein the first pull wire distal end is affixed to the intermediate segment of the distal tip and the second pull wire distal end is affixed to the proximal segment of the distal tip.