Steerable guidewire

• US 4,867,173 A
• Filed: 06/30/1986
• Issued: 09/19/1989
• Est. Priority Date: 06/30/1986
• Status: Expired due to Term

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Meadox Surgimed A/S
• Inventors: Leoni, Gianni
• Primary Examiner(s): Hindenburg, Max
• Application Number:
  US06/880,518
• Time in Patent Office: 1,177 Days
• Field of Search: 128/656-658, 128/772, 604/95, 604/164, 604/170
• US Class Current: 600/585
• CPC Class Codes: A61M 2025/09175 having specific characteristics at the distal tip
• CPC Class Codes: A61M 25/0108 using radio-opaque or ultrasound markers
• CPC Class Codes: A61M 25/09033 with fixed mandrils, e.g. mandrils fixed to tip; Tensionable wires

Abstract

A small diameter steerable guidewire with uniform flexibility in its distal region particularly well suited for PTCA use is provided. The guidewire has a diameter of less than 0.50 mm and is formed from an elongated substantially cylindrical main core wire with a distal cylindrical region of reduced diameter at the distal end of the core wire. A safety wire is attached to the distal end of the region of reduced diameter and a safety tip attached to the distal end of the safety wire and coil. The safety wire and coil may be formed of a radio opaque material so the position of the wire can be accurately determined when in use.

Claims

1. A small diameter steerable guidewire comprising:

an elongated core wire having a main wire portion with a substantially cylindrical configuration of uniform diameter with a proximal end and a distal end and having a distal cylindrical region of reduced diameter at the distal end;

the distal cylindrical region being of uniform diameter which is smaller than the main wire portion;

the distal end of the main wire portion formed with a shoulder region with the distal cylindrical region extending from the main wire portion at the shoulder region, the shoulder region providing a sharp transition between the main wire portion and the distal cylindrical region for providing a guidewire having improved uniform bendability;

a substantially cylindrical safety wire having a diameter less than the distal cylindrical region secured to the distal end of the distal cylindrical region and extending therefrom;

a coil attached to the distal end of the main wire portion surrounding the distal cylindrical region;

the coil having a diameter substantially equal to the diameter of the main wire portion for providing a smooth transition between the outer surface of the main wire portion and coil;

a safety tip secured to the coil at its distal end, with the safety wire extending from the distal end of the distal cylindrical region to the tip;

the coil having a distal region located towards the safety tip and a proximal region located towards the main wire portion, and wherein the turns of the coil are more tightly packed, considered in the axial direction, in the distal region of the coil than in the proximal region of the coil to provide increased bendability to the coil at the proximal region of the coil; and

the length of the coil being small relative to the length of the main wire portion.

2. The guidewire of claim 1, wherein the main wire portion is coated with a friction less material.

3. The guidewire of claim 2, wherein the frictionless material is polytetrafluoroethylene.

4. The guidewire of claim 1, wherein the diameters of the main wire portion and the coil are substantially equal and less than 0.50 mm.

5. The guidewire of claim 1, wherein the coil is formed from a radio opaque material.

6. The guidewire of claim 5, wherein the radio opaque material is an alloy of wolfram and platinum.

7. The guidewire of claim 1, wherein the wires are formed of stainless steel.

8. The guidewire of claim 1, wherein the coil attachment to the distal end of the main wire portion is a point welding attachment to the shoulder region of the main wire portion.

9. A small diameter steerable guidewire, comprising:

an elongated core wire having a main wire portion with a substantially cylindrical configuration of uniform diameter with a proximal end and a distal end and having a distal cylindrical region of reduced diameter at the distal end;

the distal cylindrical region being of uniform diameter which is smaller than the main wire portion;

the distal end of the main wire portion formed with a shoulder region with the distal cylindrical region being coaxial with the main wire portion, extending from the main wire portion at the shoulder region, the shoulder region providing a sharp transition between the main wire portion and the distal cylindrical region for providing a guidewire having improved uniform bendability;

a substantially cylindrical safety wire which is coaxial with the main wire, the safety wire having a diameter less than the distal cylindrical region and being secured to the distal end of the distal cylindrical region and extending therefrom;

the substantially cylindrical safety wire secured to the distal end of the distal cylindrical region coaxial with the main wire;

a coil attached to the distal end of the main wire portion surrounding the distal cylindrical region;

the coil having a diameter substantially equal to the diameter of the main wire portion for providing a smooth transition between the outer surface of the main wire portion and coil;

a safety tip secured to the coil at its distal end, with the safety wire extending from the distal end of the distal cylindrical region to the tip;

the coil having a distal region located towards the safety tip and a proximal region located towards the main wire portion, and wherein the turns of the coil are more tightly packed, considered in the axial direction, in the distal region of the coil than in the proximal region of the coil to provide increased bendability to the coil at the proximal region of the coil; and

the length of the coil being small relative to the length of the main wire portion.

10. The guidewire of claim 9, wherein the safety wire is formed of a radio opaque material.

11. The guidewire of claim 10, wherein the radio opaque material is an alloy of wolfram and platinum.

12. The guidewire of claim 9, wherein the coil attachment to the distal end of the main wire portion is a point welding attachment to the shoulder region of the main wire portion.

13. A small diameter steerable guidewire, comprising:

an elongated cylindrical wire having a main wire portion with a diameter less than 0.50 mm with a proximal end and a distal end and the main wire portion coated with a frictionless material, the distal end being formed with a shoulder region;

a cylindrical distal region of a smaller diameter than the main wire portion formed at the distal end of the main wire portion with the shoulder region constituting a sharp transition between the greater diameter of the main wire portion and the smaller diameter of the distal cylindrical region for providing a guidewire having improved uniform bendability;

a cylindrical safety wire secured to the distal end of the distal cylindrical region;

a coil having a distal end and a proximal end attached to the distal end of the main wire portion and arranged in turns which surround the distal cylindrical region and the safety wire, the coil having a uniform diameter equal to the diameter of the main core wire portion for forming a smooth transition along the outer surface of the main wire portion and the coil;

a safety tip secured to the distal end of the coil and safety wire;

the coil having a distal region located towards the safety tip and a proximal region located towards the main wire portion, and wherein the turns of the coil are more tightly packed, considered in the axial direction, in the distal region of the coil than in the proximal region of the coil to provide increased bendability to the coil at the proximal region of the coil; and

the length of the coil being small relative to the length of the main wire portion.

14. The guidewire of claim 13, wherein the coil is formed of a radio opaque material.

15. The guidewire of claim 13, wherein the safety wire is made of a radio opaque material.

16. The guidewire of claim 13, wherein the coil attachment to the distal end of the main wire portion is a point welding attachment to the shoulder region of the main wire portion.