Catheter With Knit Section

• US 20110024025A1
• Filed: 10/18/2010
• Published: 02/03/2011
• Est. Priority Date: 06/12/1998
• Status: Active Grant

• Current Assignee: Target Therapeutics, Inc. (Boston Scientific Corporation)
• Original Assignee: Target Therapeutics, Inc. (Boston Scientific Corporation)
• Inventors: Bardsley, Earl, Garabedian, Robert, McFadden, Jill M.
• Granted Patent: US 8,181,324 B2
• Time in Patent Office: Days
• US Class Current: 156/149
• CPC Class Codes: A61B 5/6852 Catheters
• CPC Class Codes: A61M 25/0045 multi-layered, e.g. coated coating materials A61L29/08
• CPC Class Codes: A61M 25/0053 having a variable stiffness along the longitudinal axis, e.g. by varying the pitch of the coil or braid
• CPC Class Codes: A61M 25/0054 with regions for increasing flexibility
• CPC Class Codes: Y10T 29/49801 Shaping fiber or fibered material

Abstract

A catheter section comprising an elongate tubular member having a proximal end, a distal end, and a passageway defining a lumen extending between the proximal and distal ends. The elongate tubular member includes a knit tubular member and an inner tubular liner in coaxial relationship with the knit tubular member. The catheter section is for use as a distal section in a catheter having a relatively stiff proximal section.

Claims

1. A method for manufacturing a catheter shaft, the method comprising:

forming an inner polymeric tubular member;

knitting an intermediate member from a wire;

disposing the intermediate member over the inner tubular member; and

disposing an outer tubular member over the intermediate tubular member and the inner tubular member.

2. The method of claim 1, wherein the intermediate member is formed of a plurality of knit loops.

3. The method of claim 2, wherein the intermediate member is formed from a single strand.

4. The method of claim 3, wherein the single strand forms a plurality of up loops and a plurality of down loops.

5. The method of claim 4, wherein the plurality of up loops interlock with the plurality of down loops of the single strand.

6. The method of claim 1, wherein the intermediate member comprises a metal alloy.

7. The method of claim 1, wherein the intermediate member comprises a non-metallic material.

8. The method of claim 1, wherein the inner tubular member and the outer tubular member are in a coaxial relationship with the knit member.

9. The method of claim 2, wherein the knit member is tightly knitted such that it is generally not radially expandable.

10. The method of claim 1, wherein the outer tubular member is heat-shrunk over the intermediate member and the inner tubular member.

11. The method of claim 1, wherein the outer tubular member is extruded over the intermediate member and the inner tubular member.

12. A method for manufacturing a multi-layered catheter shaft having a proximal end, a distal end, and a passageway defining a distal end disposed between the proximal end and the distal end, the method comprising:

forming an inner polymeric tubular member;

knitting an intermediate member from a single wire to form a plurality of up loops interlocking with a plurality of down loops;

disposing the intermediate member over the inner tubular member; and

disposing an outer tubular member over the intermediate tubular member and the inner tubular member;

wherein the distal end of the catheter shaft is more flexible than the proximal end.

13. The method of claim 12, wherein the intermediate member comprises a metal alloy.

14. The method of claim 12, wherein the intermediate member comprises a non-metallic material.

15. The method of claim 12, wherein the knit member is tightly knitted such that it is generally not radially expandable.

16. A method for manufacturing a catheter shaft having a proximal end, a distal end, and a passageway defining a distal end disposed between the proximal end and the distal end, the method comprising:

forming an inner polymeric tubular member having a proximal end and a distal end;

knitting an intermediate member from a single wire to form a plurality of up loops interlocking with a plurality of down loops;

disposing the intermediate member over a distal portion of the inner tubular member;

disposing a stiffening member over a proximal portion of the inner tubular member; and

disposing an outer tubular member over the intermediate tubular member, the stiffening member, and the inner tubular member;

wherein the distal end of the catheter shaft is more flexible than the proximal end.

17. The method of claim 16, wherein the stiffening member comprises a helically wound coil.

18. The method of claim 16, wherein the stiffening member comprises a braided member.

19. The method of claim 16, wherein the stiffening member comprises a metal alloy.

20. The method of claim 16, wherein the knit member is tightly knitted such that it is generally not radially expandable.