GUIDEWIRE

• US 20110160705A1
• Filed: 12/20/2010
• Published: 06/30/2011
• Est. Priority Date: 12/25/2009
• Status: Active Grant

• Current Assignee: Asahi Intecc Company Limited
• Original Assignee: Asahi Intecc Company Limited
• Inventors: TAKAHASHI, Masayuki, MATSUMOTO, Satoru
• Granted Patent: US 8,622,932 B2
• Time in Patent Office: Days
• US Class Current: 604/529
• CPC Class Codes: A61M 2025/09083 having a coil around a core
• CPC Class Codes: A61M 2025/09133 having specific material compositions or coatings; Materials with specific mechanical behaviours, e.g. stiffness, strength to transmit torque
• CPC Class Codes: A61M 2025/09166 having radio-opaque features
• CPC Class Codes: A61M 25/09 Guide wires

Abstract

An object of the present invention is to provide a guidewire having high safety and improved flexibility and rotation followability. This guidewire has an inner coil that surrounds a distal side portion of a core shaft, and an outer coil that surrounds the inner coil and the distal side portion of the core shaft. A front end of the outer coil and a front end of the inner coil are joined to a tip of the core shaft by a tip plug. Further, the guidewire has a coil joint that joins only the outer coil and the inner coil to each other. With this configuration, the flexibility of the inner coil is maintained. Moreover, rotation of a proximal side of the guidewire is transmitted to the inner coil not only from the core shaft but also from the outer coil. This leads to improvement in rotation followability.

Claims

1. A guidewire comprising:

a core shaft;

an inner coil that is formed by winding at least one strand, and surrounds a distal side portion of the core shaft;

an outer coil that is formed by winding at least one strand, and surrounds the inner coil and the distal side portion of the core shaft;

a tip joint that joins a front end of the outer coil and a front end of the inner coil to a tip of the core shaft;

an outer rear end joint that joins a rear end of the outer coil to the core shaft;

an inner rear end joint that joins a rear end of the inner coil to the core shaft on a front side of the outer rear end joint; and

a coil joint that is located between the tip joint and the inner rear end joint, and joins only the outer coil and the inner coil to each other.

2. The guidewire according to claim 1, wherein the outer coil has an open coiled portion, with coils of the strand spaced from one another, on a front side of the coil joint.

3. The guidewire according to claim 1, wherein the outer coil has a close coiled portion, with coils of the strand are substantially in contact with one another on a rear side of the coil joint.

4. The guidewire according to claim 1, wherein

the outer coil has a radiopaque portion, made up of the strand of a radiopaque material, on a front end side of the outer coil while having a radiotransparent portion, made up of the strand of a radiolucent material, on a rear end side of the outer coil,

the radiopaque portion has an open coiled portion, with coils of strand spaced from one another and wound in an open coiled manner, on a front end side of the radiopaque portion while having a close coiled portion, with coils of strand being substantially in contact with one another and wound in a close coiled manner, on a rear end side of the radiopaque portion, and

the coil joint joins the outer coil with the inner coil in the close coiled portion of the radiopaque portion.

5. The guidewire according to claim 4, wherein the radiotransparent portion is wound in a close coiled state where the coils of the strand are substantially in contact with one another.

6. The guidewire according to claim 1, wherein the distal side portion of the core shaft is provided with a flat portion having at least two opposed plane portions.

7. The guidewire according to claim 1, wherein the inner coil is a hollow stranded coil formed by stranding a plurality of strands.

8. A guidewire comprising:

a core shaft;

an inner coil that is formed by stranding a plurality of strands, and surrounds a distal side portion of the core shaft;

an outer coil that is formed by winding at least one strand, has an open coiled portion, on a front side of the outer coil, where coils are wound so as to be spaced from one another, while having a close coiled portion, on a rear side of the outer coil, where the strands are wound so as to come into substantially contact with one another, and surrounds the inner coil and the distal side portion of the core shaft;

a tip joint that joins a front end of the outer coil and a front end of the inner coil to a tip of the core shaft;

an outer rear end joint that joins a rear end of the outer coil to the core shaft; and

an inner rear end joint that joins a rear end of the inner coil only to the core shaft on a rear side of the open coiled portion of the outer coil as well as on a front side of the outer rear end joint.

9. The guidewire according to claim 8, wherein

the outer coil has a radiopaque portion, on a front end side of the outer coil, which is made up of strand of a radiopaque material and at least part of the front end side of which is the open coiled portion, while having a radiotransparent portion, on a rear end side of the outer coil, which is made up of strand of a radiolucent material and only includes the close coiled portion, and

the inner rear end joint of the inner coil is located on a rear side of the radiopaque portion.

10. The guidewire according to claim 8, wherein

the outer coil has an outer intermediate joint that joins the outer coil to the core shaft in between the tip joint and the outer rear end joint, and

the inner rear end joint of the inner coil is located on the front side of the outer intermediate joint.

11. The guidewire according to claim 10, wherein

the outer intermediate joint of the outer coil is located in an intermediate taper part as a portion tapering toward the tip of the core shaft,

the inner rear end joint of the inner coil is located in a front taper part, tapering toward the tip of the core shaft, located on a front side of the intermediate taper part, and

an inclination angle of the intermediate taper part differs from an inclination angle of the front side taper part.

12. The guidewire according to claim 8, comprising

a coil joint that joins only the outer coil and the inner coil to each other between the tip joint and the inner rear end joint of the inner coil.

13. The guidewire according to claim 12, wherein the outer coil is in a close coiled state where coils of the strand are substantially in contact with one another on a rear side of the coil joint.

14. The guidewire according to claim 8, wherein the distal side portion of the core shaft surrounded by the inner coil has at least two cylindrical portions with different diameters, which are a large-diameter flexible part and a small-diameter flexible part with a diameter smaller than that of the large-diameter flexible part.

15. The guidewire according to claim 14, wherein the small-diameter flexible part is disposed in a position corresponding to the open coiled portion of the outer coil.

16. The guidewire according to claim 8, wherein the distal side portion of the core shaft is provided with a flat portion having at least two opposed plane portions.