Catheter steering mechanism

• US 5,531,686 A
• Filed: 12/23/1994
• Issued: 07/02/1996
• Est. Priority Date: 02/02/1990
• Status: Expired due to Term

• Current Assignee: EP Technologies Incorporated (Boston Scientific Corporation)
• Original Assignee: EP Technologies Incorporated (Boston Scientific Corporation)
• Inventors: Thompson, Russell B., Lundquist, Ingemar
• Primary Examiner(s): Yasko, John D.
• Assistant Examiner(s): CERMAK, ADAM
• Application Number:
  US08/363,294
• Time in Patent Office: 557 Days
• Field of Search: 604/95, 604/104, 604/107, 604/170, 604/281, 604/282, 128/656-658, 128/772
• US Class Current: 604/95.04
• CPC Class Codes: A61B 2018/00916 with means for switching or controlling the main function of the instrument or device
• CPC Class Codes: A61B 2018/00952 rotatable
• 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 25/0136 Handles therefor
• CPC Class Codes: A61M 25/0144 having flexible regions as a result of inner reinforcement means, e.g. struts or rods
• CPC Class Codes: A61M 25/0147 with movable mechanical means, e.g. pull wires

Abstract

A steering mechanism including a steering shaft coupled to a controller which includes a handle and apparatus for manipulating the distal end of the steering shaft. The steering shaft includes a flexible coiled spring having a lead spring fixed in position with respect to a distal end thereof in the distal end of the steering shaft. One or more steering wires is affixed at the distal ends thereof to the lead spring. The steering wires extend through the steering shaft to the controller, and the steering apparatus of the controller is used to place tension on one or both of the steering wires. The attachment of the distal ends of the steering wires to the lead spring may be opposite one another or may be offset for providing greater maneuverability. Tension may be placed on the steering wires by wedges mounted transversely to the controller housing, or by rotation of a shaft mounted transversely to the controller housing, the steering wires being attached to the shaft such that rotation in one direction tenses one steering wire, and rotation in the other direction tenses the other steering wire. Two independently rotatable shafts may be used to separately control the two steering wires.

The steering shaft is adapted for insertion into a lumen of a catheter for use in guiding the distal end of the catheter to a treatment site within a patient. The steering mechanism may also be used in conjunction with tools or apparatus which must reach into difficult locations, such as engines or other machines.

Claims

1. A steering mechanism comprising:

a steering shaft having a proximal end and a distal end and a lumen therethrough;

a ferrule mounted in the steering shaft and having a distal end that terminates within the steering shaft short of the distal end of the steering shaft, the distal end of the steering shaft being free of any portion of the ferrule;

a lead spring attached to the ferrule, the lead spring having an axis and a bendable portion extending outside the distal end of the ferrule but still within the distal end of the steering shaft that is free of any portion of the ferrule for bending the distal end of the steering shaft in response to an applied force relative to the ferrule;

a steering wire extending through the lumen, said steering wire having a first end attached to the lead spring at a first location outside the distal end of the ferrule and having a second end exiting the proximal end; and

a controller positioned at the proximal end and attached to the second end of said steering wire for placing tension on said steering wire, for applying force to said steering wire to bend the distal end of the steering shaft toward said tensed steering wire.

2. The steering mechanism of claim 1, wherein the controller includes:

a housing connected to the steering shaft;

a shaft rotatably mounted in the housing, with the second end of said steering wire being attached to the shaft;

means attached to the shaft for rotating the shaft, for placing tension on the steering wire.

3. The steering mechanism of claim 1, wherein the controller includes

a housing connected to the steering shaft;

control element means mounted in the housing, with the second end of said steering wire being attached to the control element means, the control element means being operable for placing tension on said steering wire; and

a manually movable element accessible outside the housing and attached to the control element means for placing tension on said steering wire by operation of the control element means.

4. A steerable catheter including

a handle,

a steering shaft having a proximal end attached to the handle and a distal end and a lumen therethrough;

a ferrule mounted in the steering shaft and having a distal end that terminates within the steering shaft short of the distal end of the steering shaft, the distal end of the steering shaft being free of any portion of the ferrule;

a lead spring attached to the ferrule, the lead spring having an axis and a bendable portion extending outside the distal end of the ferrule but still within the distal end of the steering shaft that is free of any portion of the ferrule for bending the distal end of the steering shaft in response to an applied force relative to the ferrule;

a steering wire extending through the lumen, said steering wire having a first end attached to the lead spring at a location outside the distal end of the ferrule and having a second end exiting the proximal end; and

a controller positioned on the handle and attached to the second end of said steering wire, for placing tension on said steering wire for applying force to said steering wire to bend the distal end of the steering shaft toward said tensed steering wire.

5. A steering mechanism, including:

a steering shaft having a proximal end and a distal end and a lumen therethrough;

a ferrule mounted in the steering shaft;

a lead spring attached to the ferrule, the lead spring being positioned within the distal end and fixed in place relative to the ferrule;

a steering wire extending through the lumen said steering wire having a first end attached to the lead spring and having a second end exiting the proximal end;

a controller positioned at the proximal end and attached to the second end of said steering wire for placing tension on said steering wire for causing the distal end to bend toward said tensed steering wire, the controller comprising

a housing connected to the steering shaft;

a shaft rotatably mounted in the housing, with the second end of said steering wire being attached to the shaft; and

means attached to the shaft for rotating the shaft, for placing tension on said steering wire.

6. A steering mechanism comprising:

a steering shaft having a proximal end and a distal end and a lumen therethrough;

a ferrule mounted in the steering shaft and having a distal end that terminates within the steering shaft short of the distal end of the steering shaft;

a lead spring attached to the ferrule, the lead spring extending outside the distal end of ferrule but still within the distal end of the steering shaft for bending the distal end of the steering shaft in response to an applied force relative to the ferrule;

a steering wire extending through the lumen, said steering wire having a first end attached to the lead spring at a location outside the distal end of the ferrule and having a second end exiting the proximal end; and

a controller positioned at the proximal end and attached to the second end of said steering wire for placing tension on said steering wire for applying force to said steering wire to bend the distal end of the steering shaft toward said tensed steering wire, the controller comprising

a housing connected to the steering shaft;

a control element mounted in the housing, with the second end of said steering wire being attached to the control element; and

a manually movable knob for placing tension on said steering wire by operating the control element.

7. A steering mechanism comprising:

a steering shaft having a proximal end and a distal end and a lumen therethrough;

a ferrule mounted in the steering shaft and having a distal end that terminates within the steering shaft short of the distal end of the steering shaft;

a lead spring attached to the ferrule, the lead spring extending outside the distal end of ferrule but still within the distal end of the steering shaft for bending the distal end of the steering shaft in response to an applied force relative to the ferrule;

a steering wire extending through the lumen, said steering wire having a first end attached to the lead spring at a location outside the distal end of the ferrule and having a second end exiting the proximal end; and

a controller positioned at the proximal end and attached to said second steering wire end for placing tension on said steering wire for applying force to said steering wire to bend the distal end of the steering shaft toward the tensed steering wire, the controller comprising

a housing connected to the steering shaft;

control element means mounted in the housing, with the second end of said steering wire being attached to the control element means, the control element means being operable for placing tension on said steering wire; and

a manually movable element accessible outside the housing and attached to the control element means for placing tension on the steering wire by operation of the control element means.