Steering mechanism for bi-directional catheter

Patent metadata

Field	Value
Publication number	US-8956322-B2
Application number	US-201213719143-A
Country	US
Kind code	B2
Filing date	Dec 18, 2012
Priority date	Jun 15, 2004
Publication date	Feb 17, 2015
Grant date	Feb 17, 2015

Abstract

The present invention provides a bi-directional catheter with nearly double the throw in its catheter tip deflection. In particular, the travel path of each the puller wire includes a U-turn or doubling-back around a pulley which minimizes the offset angle between the puller wire and the longitudinal axis of the control handle while maximizing the travel distance of that puller wire for any given distance traveled by the pulley drawing the puller wire. In one embodiment, the catheter has an elongated catheter body, a catheter tip section with first and second diametrically-opposed off-axis lumens, and a control handle which includes a steering assembly having a lever structure carrying a pair of pulleys for simultaneously drawing and releasing corresponding puller wires to deflect the tip section of the catheter.

First claim

What is claimed is:

1. A bi-directional catheter comprising:
an elongated catheter body having proximal and distal ends;
a catheter tip section at the distal end of the catheter body and having first and second diametrically-opposed off-axis lumens;
a control handle at the proximal end of the catheter body, the control handle having a housing comprising two housing members that can be joined to enclose a steering assembly;
first and second puller wires configured to deflect the tip section in response to the steering assembly;
the steering assembly comprising:
a lever structure rotatable about an axis substantially perpendicular to a longitudinal axis of the control handle, the steering assembly including at least two pulleys rotatably mounted on opposing portions of the lever structure, wherein the first puller wire extends into the first lumen in the tip section and the second puller wire extends into the second lumen in the tip section, and wherein a distal end of each of the first and second puller wires is anchored to the tip section, wherein each of the first and second puller wires is trained on a respective pulley and rotation of the lever structure results in proximal movement of one of said pulleys relative to the control handle thereby drawing proximally at least a segment of its respective first or second puller wire for deflecting the tip section in the direction of the off-axis lumen in which that first or second puller wire extends, and
wherein a travel path of each of the first and second puller wires within the housing comprises a first generally linear path, a second generally non-linear path, and a third generally linear path;

wherein the steering assembly is operational on the puller wires to deflect the puller wires without the housing members being joined.

2. A bi-directional catheter of claim 1 , wherein each of the first and second puller wires is trained about its respective pulley for at least about 180 degrees.

3. A bi-directional catheter of claim 1 , wherein each of the first and second puller wires extends from a distal end of the control handle to its respective pulley at an angle of no greater than about 10 degrees from the longitudinal axis of the control handle.

4. A bi-directional catheter of claim 1 , wherein each of the first and second puller wires extends from a distal end of the control handle to its respective pulley at an angle ranging between about 3 and 10 degrees from the longitudinal axis of the control handle.

5. A bi-directional catheter of claim 1 , wherein the control handle further comprises a deflection knob, wherein the deflection knob and the lever structure are rotationally coupled to each other.

6. A bi-directional catheter of claim 5 , further comprising an adjustment knob configured to adjust tension of the deflection knob.

7. A bi-directional catheter of claim 6 , wherein the adjustment knob comprises a dial.

8. A bi-directional catheter of claim 7 , wherein the adjustment knob further comprises a member configured to draw the lever structure toward the housing in response to rotation of the dial.

9. A bi-directional catheter of claim 1 , further comprising:
first and second constant force springs;
a first stop positioned proximal a first connection between the first constant force spring and a proximal end of the first puller wire;
a second stop positioned proximal a second connection between the second constant force spring and a proximal end of the second puller wire.

10. A bi-directional catheter of claim 9 , wherein the first and second stops prevent the proximal ends of the first and second puller wires from moving proximally beyond a respective threshold location along the longitudinal axis of the control handle.

11. A bi-directional catheter of claim 1 , wherein the constant force springs are positioned distal of the pulleys.

12. A bi-directional catheter of claim 1 , further comprising a divider extending along the longitudinal axis of the control handle, said divider directing the first and second puller wires at a threshold angle toward their respective pulleys.

13. A bi-directional catheter of claim 1 , wherein the lever structure rotates within a threshold range of angles from the axis substantially perpendicular to the longitudinal axis of the control handle.

14. A bi-directional catheter of claim 13 , wherein the threshold range is dependent on a profile of the control handle.

15. A bi-directional catheter of claim 13 , wherein the threshold range is about −50 to +50 degrees.

16. A bi-directional catheter comprising:
an elongated catheter body having proximal and distal ends;
a catheter tip section at the distal end of the catheter body comprising first and second diametrically-opposed off-axis lumens;
a control handle at the proximal end of the catheter body, the control handle having a longitudinal axis and comprising at least a steering mechanism having a lever structure rotatable about an axis substantially perpendicular to the longitudinal axis, the steering mechanism further including at least two pulleys rotatably mounted on opposing portions of the lever structure, the control handle having two housing members that can be joined to enclose the steering assembly;
first and second puller wires, each of the first and second puller wires having proximal and distal ends and extending from the control handle through the catheter body, wherein the first puller wire extends into the first diametrically-opposed off-axis lumen in the tip section and the second puller wire extends into the second diametrically-opposed off-axis lumen in the tip section, and wherein the distal end of each of the first and second puller wires is anchored to the tip section, and wherein a travel path of each of the first and second puller wires within the control handle includes a first generally linear path, a second generally non-linear path including a U-turn of at least 180 degrees about a respective pulley, and a third generally linear path;
wherein rotation of the lever structure results in movement of one of said pulleys relative to the control handle thereby drawing at least a segment of its respective first or second puller wire for deflecting the tip section in the direction of the diametrically-opposed off-axis lumen in which that first or second puller wire extends; and
wherein the steering assembly is operational on the first and second puller wires to deflect the first and second puller wires without the housing members being joined.

17. A bi-directional catheter of claim 16 , wherein the proximal end of each of the first and second puller wires is connected to a constant force spring.

18. A bi-directional catheter of claim 16 , wherein a travel distance of a segment of one of the first or second puller wires drawn by its respective pulley for deflection is about twice the travel distance of that pulley.

19. A bi-directional catheter of claim 16 , wherein a segment of one of the first or second puller wires drawn by its respective pulley for deflection extends at an angle of less than about 7 degrees from the longitudinal axis of the control handle.

Assignees

• Biosense Webster Inc

Inventors

• Selkee Thomas V

Classifications

• A61M25/005

  with embedded materials for reinforcement, e.g. wires, coils, braids · CPC title

• A61M25/0147 Primary

  with movable mechanical means, e.g. pull wires · CPC title

• A61M25/0136 Primary

  Handles therefor · CPC title

• A61M25/0082

  Catheter tip comprising a tool · CPC title