WO2003086523A1

WO2003086523A1 - Guide wire for medical treatment

Info

Publication number: WO2003086523A1
Application number: PCT/JP2003/004487
Authority: WO
Inventors: Takashi Kawabata; Seiji Shimura
Original assignee: Japan Lifeline Co., Ltd
Priority date: 2002-04-12
Filing date: 2003-04-09
Publication date: 2003-10-23
Also published as: JP2003299739A

Abstract

A guide wire for medical treatment, comprising a wire body (4) having a distal end side small diameter part (4a) and a proximal end side large diameter part (4b) having an outer diameter rather larger than the distal end side small diameter part (4a) and a coiled spring (12) fitted to the outer periphery of the distal end side small diameter part (4a) of the wire body (4) along the axial direction and connected to the wire body (4) at the proximity and distal ends, wherein coil elements (12a) forming the coiled spring (12) are spot-welded to each other at least at one position every 100 pitches or less.

Description

Description Medical guidewire

[0 0 0 1]

Technical field

The present invention relates to a medical guidewire for guiding a medical device such as a catheter used for treatment or examination to a predetermined position in a body cavity such as a blood vessel, and more particularly, to a medical guidewire having a distal end. A medical guidewire that excels in flexibility and that transmits rotational torque at the proximal end to the distal end, and has excellent operability and insertion characteristics.

[0 0 0 2]

Background art

The catheter may need to be inserted into the vessel for treatment or testing. A catheter is generally excellent in flexibility, and it is difficult to push a catheter to a predetermined position inside a blood vessel by itself. Therefore, it is common practice to insert a guide wire into the blood vessel in advance and guide the catheter to a predetermined position in the blood vessel along the guide wire.

[0 0 0 3]

The guide wire needs to be inserted into a meandering blood vessel so as not to damage the inner wall of the blood vessel. In addition, when the distal end of the guidewire is located in an arterial blood vessel near the heart, the distal end of the guidewire often passes through a portion bent to R = 20 mm or less. In this case, if permanent deformation occurs, it will be difficult to send the material beyond that point. Therefore, it is important that the guidewire has excellent flexibility, particularly at the distal end (distal end).

[0 0 0 4]

Therefore, as a conventional guide wire, the outer diameter of the guide wire at the distal end portion is made smaller than that of the other portions, and a coil spring is attached to the outer periphery of the distal end portion. There has been proposed a guide wire which improves the performance.

[0 0 0 5] However, if the outer diameter of the guide wire at the distal end portion is made smaller than that at the other portions, the rotational torque at the proximal end portion, which is the operation side end, can be transmitted well to the distal end. It becomes difficult. Therefore, it becomes difficult to rotate the distal end of the guide wire around the axis at a predetermined angle, and there is a possibility that the penetration of the guide wire into a body cavity such as a blood vessel may be reduced.

[0 0 0 6]

Disclosure of the invention

The present invention has been made in view of such circumstances, and has as its object that the guide wire has sufficient bending flexibility at the distal end, and furthermore, the rotational torque at the proximal end is good up to the distal end. An object of the present invention is to provide a low-cost medical guidewire that is excellent in operability and insertion characteristics, is easy to manufacture, and is easy to manufacture.

[0 0 0 7]

In order to achieve the above object, a medical guidewire according to the present invention includes:

A main body having a distal end side small diameter portion and a proximal end side large diameter portion having an outer diameter relatively larger than the distal end side small diameter portion;

A medical guidewire attached to the outer periphery of a small-diameter portion on the distal end side of the wire body along an axial direction, and having a coil spring joined to the wire body at a proximal end and a distal end. hand,

The coil elements constituting the coil spring are spot-joined to each other at at least one force point at a pitch of 100 or less.

[0 0 0 8]

In the medical guide wire according to the present invention, the coil element constituting the coil spring is spot-joined at at least one force point at a pitch of 100 or less. Therefore, the rotational torque transmitted from the large-diameter portion on the proximal end side of the wire body together with the small-diameter portion on the distal end side is transmitted through the coil spring without impairing the flexibility of the coil spring. Transmits well to the distal end. Therefore, the medical guidewire of the present invention transmits the rotational torque on the proximal end side well to the distal end side, and is excellent in operability and insertion characteristics. In addition, at several places in the axial direction of the coil spring, the coil elements are spot-joined to each other by spot welding. It is easy to manufacture and low cost because it only needs to be done.

[0 0 0 9]

In the present invention, the coil element means a unit of one turn of a coil-shaped wire rod constituting a coil spring. One pitch means one unit in the axial direction of the coil element in one round. In the present invention, the cross-section of the coiled wire constituting the coil spring is not particularly limited, and is generally circular, but may be rectangular, square, or another shape.

[0 0 1 0]

Preferably, the coil elements are spot-joined at one or more places in 1 to 10 pitches.

Preferably, the spot joining portions joined in a spot manner are offset at a predetermined angle in the circumferential direction at positions adjacent to each other in the axial direction.

[0 0 1 1]

If the number of spot joints is too close to the outer circumference of the coil spring, the flexibility of the coil spring tends to decrease, and if it is too coarse, it is difficult to transmit the rotational torque via the coil spring. Tends to be. Therefore, the above range is preferable.

[0 0 1 2]

Further, in the present invention, by offsetting the spot joints at a predetermined angle in the circumferential direction at positions adjacent to each other in the axial direction, it is possible to reduce the anisotropy in the flexibility of the coil spring, and to reduce the orientation in all directions. And excellent flexibility can be obtained. As a result, the insertion characteristics of the medical guidewire are improved.

[0 0 1 3]

BRIEF DESCRIPTION OF THE FIGURES

Hereinafter, the present invention will be described based on embodiments shown in the drawings. Here, FIG. 1 is a cross-sectional side view of a main part of a medical guidewire according to one embodiment of the present invention, FIG. 2A is a side view of the coil spring shown in FIG. 1, and FIG. 2B is a view shown in FIG. — Cross section along the Β 、 line,

FIG. 3 is a schematic view showing an example of use of the guide wire shown in FIG. [0014]

BEST MODE FOR CARRYING OUT THE INVENTION

As shown in FIG. 1, the medical guide wire 2 according to one embodiment of the present invention has a wire having a distal end side small diameter portion 4a having an outer diameter smaller than the proximal end side large diameter portion 4b. It has a main body 4. The wire main body 4 is integrally formed of a wire having a substantially circular cross section, and is tapered from the proximal end large diameter portion 4b to the distal end small diameter portion 4a.

[0015]

Although the material of the wire body 4 is not particularly limited, metals such as stainless steel (for example, SUS316, SUS304), gold, platinum, aluminum, tungsten, tantalum, and alloys thereof are exemplified. In form, it is composed of stainless steel.

[0016]

The total length of the wire body 4 varies depending on the purpose of use and the like, and is not particularly limited. A coil spring 12 is mounted on the outer periphery of the small diameter portion 4 a on the distal end side of the wire main body 4. The axial length L 0 of the coil spring 12 is, for example, about 30 to 800 m.

The outer diameter of the large diameter portion 4b on the proximal end side of the wire body 4 is not particularly limited, but is about 0.10 to 0.90 mm. The outer diameter of the distal end side small diameter portion 4a is not particularly limited, but is preferably about 1/5 to 1/2 the outer diameter of the proximal end side large diameter portion 4b. It is.

[0017]

A spherical or hemispherical ball portion 10 is joined to the distal end of the distal end side small diameter portion 4 a of the wire main body 4. The ball portion 10 is a portion for smoothing the distal end portion of the guide wire 2 so as to prevent the inner wall of the body cavity from being damaged when the guide wire 2 is inserted into a body cavity such as a blood vessel. Stopper at the distal end. The ball portion 10 is made of, for example, a metal such as tin, silver, or gold, and is joined to the distal end of the distal-end-side small-diameter portion 4a by means of welding or joining. The outer diameter of the ball portion 10 is preferably approximately 0.5 to 2 times the outer diameter of the large-diameter portion 4 b on the proximal end side of the wire body 4. [0 0 1 8]

The distal end 14 of the coil spring 12 is joined to the back surface of the ball portion 10 by means of welding or joining. The proximal end 16 of the coil spring 12 is joined to the outer periphery of the wire body 4 near the proximal end of the small-diameter portion 4a on the distal end side by means of welding or joining.

[0 0 1 9]

The outer peripheral surface of the wire main body 4 may be integrally covered with a biocompatible coating film. Examples of the biocompatible coating film include, but are not particularly limited to, ordinary polymers used for medical purposes, such as olefins such as polyethylene, nitrogen-containing polymers such as polyimide and polyamide, and siloxane polymers. Further, the coating film is not limited to the polymer, and may be an inorganic coating film such as silicon carbide, carbon such as light-emitting carbon and diamond-like carbon.

[0 0 2 0]

In this embodiment, as shown in FIG. 2A and FIG. 2B, a plurality of coil elements (units of one circumference of the coil spring) connected in the axial direction so as to constitute the coil spring 12 The elements 12a are spot-joined to each other at at least one point below the pitch of 100 (100 turns). In the example shown in the figure, as shown in FIG. 2A, every two pitches along the axial direction of the coil spring 12, and as shown in FIG. The coil elements 12a adjacent to each other in the axial direction are spot welded to each other, and a spot joint 18 is formed.

[0 0 2 1 1

Moreover, as shown in FIGS. 2A and 2B, the spot joints 18 are offset at a predetermined angle 6> in the circumferential direction at positions adjacent to each other in the axial direction. The predetermined angle 0 varies depending on the number of spots and is not particularly limited. However, it is desirable that the predetermined angle 0 be distributed substantially uniformly in the circumferential direction over the entire length of the coil. By setting the angle 6> as described above, the coil spring 12 can have excellent flexibility in all directions. [0022]

Although spot welding is not particularly limited, spot laser welding is preferably used. Although the specific conditions of the spot laser welding are not particularly limited, for example, the following conditions are exemplified.

As the laser, a YAG laser is used, and a laser beam focused by an optical system to a diameter of 50/1 is used. The pulse width of the laser is approximately ^10-3 sec, the number of pulses is 10PPS (pulse / sec), the output is 10 W.

[0023]

The outer diameter of the coil spring 12 is not particularly limited, but is preferably equal to or less than the outer diameter of the ball portion 10. The outer diameter of the wire constituting the coil spring 12 is not particularly limited, but is preferably 20 to 15 Om, and more preferably 50 to 100 m. The total length L 0 of the coil spring 12 is preferably 30 to 800 thighs.

[0024]

The material of the coil spring 12 is not particularly limited, and may be a radiation contrast material or a radiation non-contrast material. Examples of the radiological contrast material include platinum, a platinum alloy (for example, Pt / Ir = 93/7), gold, a copper-copper alloy, tungsten, and tantalum, which have a good X-ray contrast property. The radiation non-contrast material is not particularly limited, but is mainly exemplified by stainless steel (for example, SUS 316 and SUS 304).

[0025]

In the medical guide wire 2 according to the present embodiment, the rotating torque transmitted from the large-diameter portion 4b on the proximal end side of the wire main body 4 is transmitted to the distal end without impairing the flexibility of the coil spring 12. Along with the side small diameter portion 4a, the power is well transmitted to the ball portion 10 mounted on the most distal end of the wire main body 4 via the coil spring 12. Therefore, the medical guidewire 2 of the present embodiment transmits the rotational torque on the proximal end side well to the distal end side, and is excellent in operability and insertion characteristics. Therefore, it is easy to freely change the bending direction of the ball portion 10 attached to the most distal end of the wire main body 4. As a result, as shown in Fig. 3, for example, As in the case of insertion from the aorta 22 of the root to the coronary artery of the heart 20, it can be easily followed and inserted into a blood vessel having a strongly bent portion near the distal end of the wire.

[0 0 2 6]

In the guide wire 2 of the present embodiment, the coil elements 12a are spot-joined to each other at a few places in the axial direction of the coil spring 12 by, for example, spot welding from the outer periphery. Because it is only necessary, it is easy to manufacture and low cost.

[0 0 2 7]

Note that the present invention is not limited to the above-described embodiment, and can be variously modified within the scope of the present invention.

Claims

The scope of the claims

1. a wire body having a distal end side small diameter portion and a proximal end side large diameter portion having an outer diameter relatively larger than the distal end side small diameter portion;

A medical guide wire, characterized in that the coil elements constituting the coil spring are spot-joined to each other at at least one force point of less than 100 pitches.

2. The medical guide wire according to claim 1, wherein the spot-joined portions joined in a spot manner are offset at a predetermined angle in a circumferential direction at positions adjacent to each other in the axial direction.

3. The medical guidewire according to claim 1, wherein the coil elements are spot-joined to each other at one or more places at 1 to 10 pitches.

4. The medical guide wire according to any one of claims 1 to 3, wherein the entire length of the wire main body is 80 to 350 cm.

5. The medical guidewire according to any one of claims 1 to 4, wherein the coil spring has an axial length of 30 to 800 thighs.

6. The medical guidewire c according to any one of claims 1 to 5, wherein a spherical or hemispherical ball portion is joined to a distal end of the distal end side small diameter portion of the wire main body.

7. The medical guidewire according to claim 6, wherein a distal end of the coil spring is in contact with a back surface of the ball portion.

8. The medical guidewire according to any one of claims 1 to 7, wherein an outer peripheral surface of the wire main body is integrally coated with a biocompatible coating film.