JP7290451B2 - guide wire - Google Patents

Description

The present invention relates to guidewires.

For example, when inserting a medical device such as a catheter into a blood vessel, a guide wire is inserted first to guide the medical device to a site to be treated.

Such a guide wire is required to have a flexible distal end so that it can be smoothly advanced through a curved blood vessel. On the other hand, in order to prevent the U-shaped bending of the distal end of the guide wire, which may occur with this flexibility, from developing excessively in the proximal direction, for example, a tapered or stepped shape is provided in the middle of the core shaft. A technique has been proposed in which an enlarged diameter portion is provided to increase rigidity (see, for example, Patent Document 1).

U.S. Pat. No. 5,345,945

However, when a conventional guide wire as described above is used, when the bending reaches the enlarged diameter portion, the core shaft tends to be plastically bent due to a large change in rigidity. If it is pushed in without recognition, the inner wall of the blood vessel or the like may be pressed.

SUMMARY OF THE INVENTION The present invention has been made in view of the circumstances described above, and an object thereof is to provide a guide wire capable of preventing excessive deformation of the core shaft.

Some aspects of the disclosure include:
(1) a core shaft having an enlarged diameter portion that expands in the proximal direction;
a coil body arranged to cover at least the tip of the core shaft;
a tip fixing portion fixed to the tip of the coil body;
a radiopaque marker portion disposed at the distal end of the core shaft;
a guide wire in which the marker portion and the tip fixing portion are separated from each other in the longitudinal direction of the core shaft;
(2) The guide wire according to (1), wherein the distal end shape of the marker portion is a curved surface shape protruding toward the distal direction.
(3) The guide wire according to (1) or (2) above, wherein the coil body is not fixed to the marker portion,
(4) The coil body according to any one of (1) to (3) above, wherein the coil body is not fixed to the tip of the core shaft and is fixed to a portion of the core shaft other than the tip. (5) the guidewire according to any one of (1) to (4), wherein the shape of the enlarged diameter portion is tapered or stepped;
is.

In the present specification, the term "distal direction" means a direction along the longitudinal direction of the guidewire and a direction in which the distal-fixed portion is positioned with respect to the coil body. The term “proximal direction” means a direction along the longitudinal direction of the guidewire and opposite to the distal direction. In addition, the term "distal end" means the end in the distal direction of any member or site, and the term "proximal end" means the end in the direction of the proximal end in any member or site.

The present invention can provide a guide wire that can prevent excessive deformation of the core shaft.

1 is a schematic side view of the first embodiment; FIG. FIG. 4 is a partially enlarged schematic side view showing an example of the shape of a marker portion in the first embodiment; FIG. 4 is a partially enlarged schematic side view showing an example of the shape of a marker portion in the first embodiment; FIG. 4 is a partially enlarged schematic side view showing an example of the shape of a marker portion in the first embodiment; FIG. 2 is a schematic side view showing the state of use of FIG. 1; FIG. 2 is a schematic side view showing the state of use of FIG. 1; FIG. 5 is a schematic side view showing a modification of the first embodiment; FIG. 4 is a schematic side view of the second embodiment; FIG. 11 is a schematic side view showing a modification of the second embodiment; FIG. 11 is a schematic side view showing a third embodiment;

The guide wire includes a core shaft having a diameter-enlarged portion that expands in a proximal direction, a coil body arranged to cover at least a distal end of the core shaft, and a distal end anchor fixed to the distal end of the coil body. and a radiopaque marker portion disposed at the distal end of the core shaft, wherein the marker portion and the distal fixing portion are spaced apart in the longitudinal direction of the core shaft.

Hereinafter, first to third embodiments will be described with reference to the drawings, but the present invention is not limited only to the embodiments described in the drawings. Also, the dimensions of the guide wire shown in the drawings are for the purpose of facilitating understanding of the implementation, and do not correspond to the actual dimensions.

[First Embodiment]
1 is a schematic side view showing a first embodiment; FIG. The guide wire 1, as shown in FIG. 1, is generally composed of a core shaft 11, a coil body 21, a tip fixing portion 31, and a marker portion 41. As shown in FIG.

The core shaft 11 is a shaft having an enlarged diameter portion 11k that is enlarged in diameter toward the proximal direction. The enlarged diameter portion 11k of the guide wire 1 has a stepped shape. The guide wire 1 has an enlarged diameter portion 11k provided at one location in the longitudinal direction of the core shaft 11. The core shaft 11 has a small diameter portion 11a with a constant outer diameter located further in the distal direction than the enlarged diameter portion 11k. and a large-diameter portion 11b located in the proximal direction from the enlarged-diameter portion 11k and having an outer diameter larger than that of the small-diameter portion 11a.

The shape of the expanded diameter portion is such that the outer diameter of the proximal end (corresponding to the outer diameter of the large diameter portion 11b in the guidewire 1) is larger than the outer diameter of the distal end (corresponding to the outer diameter of the small diameter portion 11a in the guidewire 1). There is no particular limitation on the shape in the middle in the long axis direction, as long as it is large.

As for the dimensions of the core shaft 11 in the longitudinal direction, the total length is usually 1,800 to 3,000 mm, and the small diameter portion 11a is usually 5 mm to 100 mm. The outer diameter of the core shaft 11 is usually 0.03 mm to 0.1 mm for the small diameter portion 11a and 0.25 mm to 0.46 mm for the large diameter portion 11b.

From the viewpoint of securing the flexibility of the guide wire 1 and imparting antithrombogenicity and biocompatibility, examples of the material constituting the core shaft 11 include stainless steel such as SUS304 and superelasticity such as Ni—Ti alloy. An alloy or the like can be adopted.

The coil body 21 is a coil-shaped (helical) member arranged to cover at least the tip of the core shaft 11 . The coil body 21 is, for example, formed into a coil shape by winding the wire 21a (see FIG. 1), or formed into a coil shape by subjecting a cylindrical member to slitting or the like (not shown). can be adopted. When the wire 21a is used for the coil body 21, the wire 21a may be one or more single wires, or one or more twisted wires. However, a single wire means one single wire, and a twisted wire means a bundle of wires formed by twisting a plurality of single wires together in advance.

The diameter of the wire 21a (single wire or twisted wire) forming the coil body 21 is usually 0.01 to 0.10 mm.

From the viewpoint of securing the flexibility of the guide wire 1 and imparting antithrombogenicity and biocompatibility, the wire constituting the coil body 21 may be stainless steel such as SUS316; superelasticity such as Ni—Ti alloy. Alloys; Radiopaque metals such as platinum and tungsten can be used.

The proximal end of the coil body 21 can be joined to, for example, the stepped portion (enlarged diameter portion 11k) of the core shaft 11 . On the other hand, the tip of the coil body 21 can be joined to, for example, a tip fixing portion 31 to be described later. As a method for joining the coil body 21 to the core shaft 11 and the tip fixing portion 31, for example, a brazing method using brazing material can be adopted. Examples of the brazing material include metal brazing such as Sn--Pb alloy, Pb--Ag alloy, Sn--Ag alloy and Au--Sn alloy.

In addition, it is preferable that the coil body 21 is not fixed to the tip of the core shaft 11 and is fixed to a portion of the core shaft 11 other than the tip. Specifically, such a mode includes, for example, a guide wire 1 (see FIG. 1) in which only the proximal end of the coil body 21 is joined to the core shaft 11 at the joining portion 21b. Since the coil body 21 is not fixed to the tip of the core shaft 11 and is fixed to a portion of the core shaft 11 other than the tip, the coil body 21 and the tip of the core shaft 11 are fixed. Since this is not done, it is possible to suppress abrupt changes in rigidity at the distal end of the core shaft 11 in the long axis direction, and it is possible to further prevent plastic deformation and breakage.

The distal end fixing portion 31 is a portion fixed to the distal end of the coil body 21 . Specifically, the distal end fixing portion 31 can be formed, for example, so that the distal end portion has a substantially hemispherical shape that is convexly curved toward the distal direction. For example, the distal end of the coil body 21 is joined to the proximal end of the distal end fixing portion 31 .

The tip fixing portion 31 can be formed, for example, by melting and molding a part of a member constituting the guide wire 1 such as the coil body 21 or by melting and molding a brazing material. Examples of the brazing material include those similar to those described in the joining method of the coil body 21 .

The marker part 41 is a radiopaque member arranged at the tip of the core shaft 11 . The marker portion 41 is arranged so as to be separated from the distal end fixing portion 31 in the longitudinal direction of the core shaft 11 . The shape of the marker portion 41 is not particularly limited as long as the effects of the present invention are not impaired. 2B), a substantially disk-shaped marker portion 413 (see FIG. 2C), or the like can be employed.

Among these, it is preferable that the shape of the marker portion 41 is formed so that the distal end shape is a curved surface shape protruding toward the distal end direction. Specifically, such a curved marker portion 41 may be, for example, a substantially hemispherical marker portion 411 (see FIG. 2A) having a curved surface in the distal direction. Thereby, when the distal end portion of the guide wire 1 is bent, the coil body 21 can be smoothly bent without being caught by the marker portion 41 .

Examples of the radiopaque material forming the marker portion 41 include gold, platinum, tungsten, and alloys containing these elements (for example, platinum-nickel alloy). The material constituting the marker part 41 is, for example, a mixture of a radiolucent material and a radiopaque material, a radiopaque material coated with a radiopaque material, and the like. It may also be a combination of transparent and radiopaque materials.

As a method for joining the marker portion 41 and the core shaft 11, for example, the same method as described in the method for joining the coil body 21 can be used. Note that it is preferable that the marker portion 41 is not fixed to the coil body 21 . Since the marker portion 41 is not fixed to the coil body 21 in this way, the coil body 21 can be smoothly bent without being restrained by the marker portion 41 .

Next, the mode of use of the guidewire 1 will be described. First, the tip of the guide wire 1 is inserted into the blood vessel, and the tip of the guide wire 1 exposed outside the body is pushed forward. At that time, the guide wire 1 is usually inserted into the blood vessel after intentionally bending a portion of the distal end of the guide wire 1 in advance so that the blood vessel can be easily selected at the bifurcation of the blood vessel, for example. . Such bending may also occur inadvertently when the guidewire 1 is advanced through the blood vessel.

Here, the degree of bending of the distal end of the guide wire 1 varies depending on the degree of bending force. For example, when the bending force is small, only the distal end portion of the coil body 21 may bend without bending the small-diameter portion 11a of the core shaft 11, as shown in FIG. 3A. This is because the rigidity in the longitudinal direction of the guide wire 1 increases at the distal end of the small-diameter portion 11a of the core shaft 11 (the rigidity increases sharply toward the proximal direction). When the bending force increases, both the distal end portion of the coil body 21 and the small-diameter portion 11a of the core shaft 11 corresponding to this distal end portion can be bent, as shown in FIG. 3B. Therefore, when the bending force is small, it is possible to suppress the bending of the distal end portion of the guide wire 1 from extending in the proximal direction beyond the distal end of the small diameter portion 11a. Further, when the bending of the tip of the guide wire 1 exceeds the tip of the small diameter portion 11a, the small diameter portion 11a of the core shaft 11 is prevented from bending excessively by grasping the position of the marker portion 41 under radiation irradiation. can do. As a result, it is possible to prevent the core shaft 11 from plastically deforming due to the bending of the core shaft 11 extending to the enlarged diameter portion 11k.

Next, after the distal end of the guide wire 1 reaches the site to be treated, the proximal end of the guide wire 1 is inserted from the distal end of a medical instrument (not shown) such as a catheter into the lumen thereof, and the proximal end of the medical instrument is inserted. , the medical device is pushed along the guidewire 1 . After the medical instrument reaches the site to be treated, various treatments are performed using the medical instrument. Then, after the above treatment is completed, the medical device and the guide wire 1 are pulled out of the blood vessel, thus ending the series of procedures.

As described above, since the guide wire 1 has the above structure, it is possible to visually confirm whether or not the guide wire 1 is bent in the proximal direction beyond the distal end of the core shaft 11 by means of the marker portion 41 . Therefore, it is possible to prevent excessive deformation of the core shaft 11 (for example, plastic deformation or breakage of the core shaft 11) while observing the bent state of the small diameter portion 11a using the marker portion 41 as a clue. .

In the first embodiment described above, the guide wire 1 has one enlarged diameter portion 11k composed of the small diameter portion 11a and the large diameter portion 11b. For example, the guide wire 1m1 (see FIG. 4) may be provided with a core shaft 11m1 having two enlarged diameter portions 11km11 and 11km12 and small diameter portions 11am11 and 11am12 whose outer diameters are changed stepwise.

[Second embodiment]
FIG. 5 is a schematic side view showing the second embodiment. The guide wire 2, as shown in FIG. 5, is generally composed of a core shaft 12, a coil body 21, a tip fixing portion 31, and a marker portion 41. As shown in FIG. The guide wire 2 differs from the first embodiment in that it has a core shaft 12 . The configurations of the coil body 21, the distal end fixing portion 31, and the marker portion 41 are the same as those of the first embodiment, so the same parts are denoted by the same reference numerals, and detailed description thereof is omitted. do. Also, since the core shaft 12 is the same as that of the first embodiment except for the configuration of the core shaft 12 described below, detailed description thereof will be omitted.

The core shaft 12 is a shaft having an enlarged diameter portion 12k whose diameter is enlarged toward the proximal direction. The shape of the enlarged diameter portion 12k of the core shaft 12 in the guide wire 2 is tapered (the enlarged diameter portion 12k is also referred to as "tapered portion 12a"). The guide wire 2 has a tapered portion 12a provided at one location in the longitudinal direction of the core shaft 12. The distal end of the tapered portion 12a coincides with the distal end of the core shaft 12, and the proximal end of the tapered portion 12a has an outer diameter. It is continuous with a constant large diameter portion 12b.

The base end of the coil body 21 is joined to the tapered portion 12a of the core shaft 12 at a joining portion 21b.

As described above, in the guide wire 2, the enlarged diameter portion 12k of the core shaft 12 has a tapered shape. Therefore, excessive deformation of the core shaft 12 can be prevented while observing the degree of bending using the marker portion 41 as a clue.

In addition, in the above-described second embodiment, the guide wire 2 configured by the tapered portion 12a and the large diameter portion 12b has been described, but the guide wire 2 has a plurality of enlarged diameter portions and the outer diameter increases toward the proximal direction. It may also be a guidewire with a graduated core shaft. Such a guide wire includes, for example, a tapered portion 12am21 (expanded diameter portion 12km21) tapered from the distal end of the core shaft 12m2 toward the proximal end, a small diameter portion 12cm2 having a constant outer diameter, and a tapered portion 12cm2. A guide wire 2m2 (see FIG. 6) having a core shaft 12m2 configured in order of a tapered portion 12am22 (expanded diameter portion 12km22) and a large diameter portion 12bm2 having a constant outer diameter may be used.

[Third Embodiment]
FIG. 7 is a schematic side view showing a third embodiment; As shown in FIG. 7, the guide wire 3 is generally composed of a core shaft 12, a coil body 21, an inner coil body 51, a tip fixing portion 31, and a marker portion 43. As shown in FIG. The guide wire 3 differs from the second embodiment in that it includes an inner coil body 51 and a marker portion 43 . The configurations of the core shaft 12, the coil body 21, and the tip fixing portion 31 are the same as those of the second embodiment, so the same parts are denoted by the same reference numerals, and detailed description thereof will be omitted. do. Also, since the configurations other than the configurations of the inner coil body 51 and the marker portion 43 described below are the same as those of the second embodiment, detailed description thereof will be omitted.

The inner coil body 51 is a coil-shaped (helical) member provided inside the coil body 21 and arranged to cover at least the tip of the core shaft 12 . The inner coil body 51 is formed, for example, by winding a wire 51a into a coil shape (see FIG. 7), or by slitting a cylindrical member to form a coil shape (not shown). and can be adopted. When the wire 51a is used for the inner coil body 51, the wire 51a may be one or more single wires, or one or more twisted wires.

The diameter of the wire 51a (single wire or twisted wire) forming the inner coil body 51 is usually 0.01 to 0.10 mm.

As the wire material constituting the inner coil body 51, from the viewpoint of ensuring the flexibility of the guide wire 3 and imparting antithrombogenicity and biocompatibility, for example, the same material as that of the coil body 21 described above is adopted. be able to.

The proximal end of the inner coil body 51 can be joined to the enlarged diameter portion 12k (tapered portion 12a) of the core shaft 12 at the joining portion 51b, for example. On the other hand, the tip of the inner coil body 51 can be joined to the tip fixing portion 31, for example.

The marker portion 43 is a radiopaque member arranged at the distal end of the core shaft 12 . The marker portion 43 is arranged so as to be separated from the distal end fixing portion 31 in the longitudinal direction of the core shaft 12 . The shape of the marker portion 43 in the guide wire 3 is approximately quarter spherical. One plane 43 a of the two planes forming the approximately 1/4 spherical shape is joined to the tip of the core shaft 12 , and the other plane 43 b is arranged so as to be able to contact the inner circumference of the inner coil body 51 .

As described above, in the guide wire 3, since the shape of the marker portion 43 is substantially a 1/4 spherical shape, the guide wire 3 can contact the inner circumference of the inner coil body 51 with the other flat surface 43b. 3 (the coil body 21 and the inner coil body 51 can easily bend toward the side along the curved surface 43c of the marker portion 43). In addition, since the guide wire 3 includes the inner coil body 51, the rigidity of the guide wire 3 can be changed in multiple steps in the longitudinal direction.

In addition, the present invention is not limited to the configuration of the above-described embodiment, but is indicated by the scope of the claims, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims. be done.

For example, in the above-described embodiments, the core shafts 11 and 12 have the enlarged diameter portions 11k and 12k unilaterally enlarged from the distal end to the proximal direction, but the effects of the present invention are described. The guide wire may have a part of the core shaft that is tapered in the proximal direction as long as it does not impair the .

Also, the inner coil body 51 described above in the third embodiment is an optional component. Although not shown, the present invention can be applied, for example, to a guidewire that does not have the inner coil body 51, or to a guidewire that has an inner coil body in addition to the guidewires 1 and 2 of the first and second embodiments. may

1 to 3, 1m1, 2m2 Guide wire 11, 12, 11m1, 12m2 Core shaft 11k, 12k, 11km11, 11km12, 12km21, 12km22 Expanded part 21 Coil body 31 Tip fixation part 41, 411, 412, 413, 43 Marker part

Claims (5)

a core shaft having an enlarged diameter portion that expands in the proximal direction;
a coil body arranged to cover at least the tip of the core shaft;
a tip fixing portion fixed to the tip of the coil body;
a radiopaque marker portion disposed at the distal end of the core shaft;
Neither the distal end of the core shaft nor the marker portion is connected to the distal fixing portion, and neither the distal end of the core shaft nor the marker portion extends forward in the longitudinal direction of the core shaft . A guidewire spaced from the distal anchor. 2. The guide wire according to claim 1, wherein the tip shape of the marker portion is a curved surface shape protruding toward the tip direction. The guide wire according to claim 1 or 2, wherein the coiled body is not fixed to the marker portion. 4. The guide wire according to any one of claims 1 to 3, wherein the coil body is not fixed to the distal end of the core shaft and is fixed to a portion of the core shaft other than the distal end. 5. The guidewire according to any one of claims 1 to 4, wherein the shape of the enlarged diameter portion is tapered or stepped.

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