Mechanisms for improving the stiffness transition across a dissimilar metal weld joint

Patent metadata

Field	Value
Publication number	US-10071229-B2
Application number	US-201514686175-A
Country	US
Kind code	B2
Filing date	Apr 14, 2015
Priority date	Apr 14, 2015
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

The present disclosure is directed to multi-segment intraluminal guide wires including an elongate distal portion comprising a first metallic material (e.g., nitinol), an elongate proximal portion comprising a second metallic material (e.g., stainless steel). The distal and proximal portions may be directly joined together end to end by a solid-state weld joint. A diameter of the weld region surrounding the weld joint on either side of the weld joint may be reduced (e.g., ground down) relative to the diameter of the distal and proximal portions of the guide wire on either side of the weld region. A stiffness adjusting sleeve may be disposed over the weld joint so that a transition profile of bending stiffness across the weld region is gradual, rather than abrupt across the distal portion of the guide wire to the proximal portion of the guide wire. A polymer jacket may cover the sleeve and distal portion.

First claim

The invention claimed is:

1. A multi-segment intraluminal guide wire comprising:
an elongate first distal portion comprising a first metallic material;
an elongate second proximal portion comprising a second metallic material that is different from the first metallic material, the distal and proximal elongate portions being joined together end to end by a solid-state weld joint;
a diameter of a weld region surrounding the weld joint being reduced relative to a diameter of the distal and proximal portions of the guide wire on either side of the weld region;
a stiffness adjusting sleeve disposed over the weld joint so that a transition profile of bending stiffness across the weld region is gradual rather than abrupt across the distal portion of the guide wire to the proximal portion of the guide wire, wherein the stiffness adjusting sleeve is:
formed from a multifilar coil including multiple strands of helically wound wire disposed over the weld region so that a transition profile of bending stiffness across the weld region is gradual rather than abrupt across the distal portion of the guide wire to the proximal portion of the guide wire; or
formed from a sleeve body in which at least one end thereof is tapered in thickness so that a transition profile of bending stiffness across the weld region is gradual rather than abrupt across the distal portion of the guide wire to the proximal portion of the guide wire.

2. The multi-segment intraluminal guide wire of claim 1 , wherein the distal portion comprises nitinol and the proximal portion comprises at least one of stainless steel or a cobalt-based alloy.

3. The multi-segment intraluminal guide wire of claim 1 , wherein ends of individual strands of the multifilar coil are adhered to one another to prevent them from fraying.

4. The multi-segment intraluminal guide wire of claim 1 , wherein both ends of the stiffness adjusting sleeve are tapered.

5. The multi-segment intraluminal guide wire of claim 1 , wherein only the proximal end of the hollow cylindrical stiffness adjusting sleeve is tapered.

6. The multi-segment intraluminal guide wire of claim 1 , wherein the weld joint is disposed no more than 25 cm from a distal end of the distal portion.

7. The multi-segment intraluminal guide wire of claim 1 wherein the weld joint is disposed no more than 20 cm from a distal end of the distal portion.

8. The multi-segment intraluminal guide wire of claim 1 , wherein the weld joint is disposed no more than 15 cm from a distal end of the distal portion.

9. The multi-segment intraluminal guide wire of claim 1 , wherein the weld joint is disposed no more than 10 cm from a distal end of the distal portion.

10. The multi-segment intraluminal guide wire of claim 1 , wherein the weld joint is disposed from 3 cm to 25 cm from a distal end of the distal portion.

11. The multi-segment intraluminal guide wire of claim 1 , wherein a diameter of the distal portion is greater than a diameter of the proximal portion to aid in reducing any difference in bending stiffness between the proximal and distal portions of the guide wire.

12. The multi-segment intraluminal guide wire of claim 1 , wherein the weld joint is generally perpendicular to a longitudinal axis of the guide wire.

Assignees

• Abbott Cardiovascular Systems Inc

Inventors

• Simpson John A
• Wilson Bruce M

Classifications

• A61M2025/09091

  where a sheath surrounds the coil at the distal part · CPC title

• A61M2025/09108

  Methods for making a guide wire · CPC title

• A61M2025/0915

  having features for changing the stiffness · CPC title

• A61M2025/09133

  having specific material compositions or coatings; Materials with specific mechanical behaviours, e.g. stiffness, strength to transmit torque · CPC title

• A61M25/09 Primary

  Guide wires · CPC title