Spring assembly for catheter

• US 5,902,291 A
• Filed: 09/29/1997
• Issued: 05/11/1999
• Est. Priority Date: 10/11/1994
• Status: Expired due to Term

• Current Assignee: EP Technologies Incorporated (Boston Scientific Corporation)
• Original Assignee: EP Technologies Incorporated (Boston Scientific Corporation)
• Inventors: Houser, Russell A., Thompson, Russell B.
• Primary Examiner(s): Coggins, Wynn Wood
• Assistant Examiner(s): Sadula, Jennifer R.
• Application Number:
  US08/937,819
• Time in Patent Office: 589 Days
• Field of Search: 604/164, 604/165, 604/167-169, 604/170, 604/264, 604/280, 604/281, 604/282
• US Class Current: 604/524
• CPC Class Codes: A61M 2025/09191 made of twisted wires
• CPC Class Codes: A61M 25/0041 pre-formed, e.g. specially adapted to fit with the anatomy of body channels urethral catheters A61F2/04
• CPC Class Codes: A61M 25/0133 Tip steering devices

Abstract

A catheter having a proximal portion and a distal portion terminating in a distal tip, is provided with a spring assembly contained within its distal tip portion for providing a bias against side to side deflection of the distal tip. The assembly preferably includes a central wire having a first diameter, which central wire extends from the proximal portion of the catheter to the distal portion, and a plurality of wires secured to the central wire adjacent the distal end thereof. Each of the wires is stranded together, preferably twisted helically, around the central wire and preferably has a second diameter substantially smaller than the first diameter. Alternatively, the stranded wires can be attached along and parallel to the larger diameter wire, and the latter wire is of a substantially greater length than the stranded wires.

Claims

1. A catheter, comprising:

a catheter tube having a distal region with a terminal end and an interior lumen, which extends along an axis,

a spring enclosed within the interior lumen in the distal region, the spring formed from a material biasing the spring toward a normally straight configuration to thereby normally bias the distal region toward a straight configuration, the spring having a length measured along the axis of the interior lumen,

an anchor wire extending along the spring within the interior lumen, the anchor wire having a terminal end, the anchor wire having an entire length measured along the axis of the interior lumen greater than the length of the spring, and

an operative element carried by the terminal end of the catheter tube, wherein the terminal end of the anchor wire is attached to the operative element so that the operative element is firmly secured to the catheter tube terminal end.

2. A catheter according to claim 1

wherein the anchor wire extends for a portion of its entire length within the spring.

3. A catheter according to claim 1

wherein the anchor wire extends for its entire length outside the spring.

4. A catheter according to claim 1,

wherein the operative element comprises an electrode.

5. A catheter according to claim 4,

wherein the anchor wire further comprises a signal conduction means for the electrode.

6. A catheter according to claim 1

wherein the spring comprises a bundle of wires.

7. A catheter according to claim 6

wherein the anchor wire has a diameter, and

wherein each wire in the bundle has a diameter less than the diameter of the anchor wire.

8. A catheter according to claim 6

wherein the wires in the bundle are helically stranded.

9. A catheter according to claim 1

wherein the material of the spring comprises a metal.

10. A catheter according to claim 9

wherein the metal comprises stainless steel.

11. A catheter according to claim 9

wherein the metal comprises a cobalt-chromium-nickel alloy.