JP7364369B2 - guide wire - Google Patents

Description

TECHNICAL FIELD 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 first inserted to guide the medical device to a site to be treated.

Such a guidewire is required to have flexibility at its tip so that it can move smoothly through curved blood vessels. As a guidewire with increased flexibility at the tip, for example, a guidewire in which the cross-sectional shape of the core at the tip is non-circular has been proposed (see, for example, Patent Document 1).

According to the above guidewire, since the cross-sectional shape of the core tip is rectangular, the core can be easily bent around each side of the rectangle, and the flexibility of the guidewire tip can be improved. You can expect it.

Special Publication No. 2013-544575

However, although the conventional guidewire described above can be expected to have improved flexibility, it is difficult to rotate the guidewire when forming a through hole in a hard site such as a chronic total occlusion (CTO). It may receive resistance in the circumferential direction when it is rotated. At this time, splashes (sudden and unintentional rotation of the guidewire tip) may occur at the tip of the guidewire, which may cause damage to the inner wall of the blood vessel or the like.

The present invention has been made based on the above-mentioned circumstances, and an object thereof is to provide a guidewire that can prevent the generation of springs while maintaining the flexibility of the distal end.

Some aspects of this disclosure include:
(1) A core shaft having a distal end portion having a non-perfect circular cross-sectional shape, and a main body portion having a true circular cross-sectional shape at least in a portion continuous with the distal end portion and extending toward the proximal end side. and,
a first inner coil body wound continuously from the tip of the core shaft to the main body and in close contact with the core shaft;
an outer coil body wound to cover the first inner coil body;
A guide wire comprising: a tip fixing portion to which at least the tip of the core shaft and the tip of the outer coil body are fixed;
(2) The guide wire according to (1) above, wherein the cross-sectional shape of the distal end portion is rectangular or oval;
(3) The guide wire according to (1) or (2), wherein the first inner coil body is composed of a multi-thread coil, and (4) the guide wire is in close contact with the first inner coil body, and The guide wire according to any one of (1) to (3), further comprising a second inner coil body wound in a direction opposite to the winding direction of the first inner coil body. be.

In addition, in this specification, "the tip side" is a direction along the longitudinal direction, and means a direction in which the tip fixing part is located with respect to the core shaft. "Proximal side" means a direction along the longitudinal direction and opposite to the distal side. However, the "long axis direction" refers to the longitudinal direction of the guide wire. The term "distal end" refers to the distal end of any member or site, and the term "proximal end" refers to the proximal end of any member or site. The term "distal end" refers to a part of any member or region that includes the distal end and extends from the distal end toward the proximal end halfway in the longitudinal direction. The term "proximal end" refers to a part of any member or region that includes the proximal end and extends halfway in the longitudinal direction from the proximal end toward the distal end.

INDUSTRIAL APPLICATION This invention can provide the guidewire which can prevent the generation|occurrence|production of a spring while maintaining the flexibility of a front-end|tip part.

1 is a schematic side view showing a first embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing an example of a guide wire taken along line II-II in FIG. 1. FIG. 2 is a schematic cross-sectional view showing an example of a guide wire taken along line II-II in FIG. 1. FIG. 2 is a schematic cross-sectional view showing an example of a guide wire taken along line II-II in FIG. 1. FIG. It is a schematic side view which shows the 2nd embodiment of this invention. 4 is a schematic cross-sectional view showing an example of a guide wire cut along line IV-IV in FIG. 3. FIG. It is a schematic side view which shows the modification of 1st Embodiment. It is a schematic side view which shows the modification of 1st Embodiment. It is a schematic side view which shows the modification of 1st Embodiment.

The guide wire has a distal end portion having a non-perfect circular cross-sectional shape, and a main body portion having a true circular cross-sectional shape at least in a portion continuous with the distal end portion and extending toward the proximal end side. a core shaft, a first inner coil body that is wound continuously from the tip of the core shaft to the main body so as to be in close contact with the core shaft, and a first inner coil body that covers the first inner coil body. It includes a wound outer coil body and a tip fixing portion to which at least the tip of the core shaft and the tip of the outer coil body are fixed.

The portion of the main body that has a perfect circular cross-sectional shape is at least the portion that is continuous with the distal end and around which the first inner coil body is wound, and the portion that is closer to the proximal end is circular or has a circular cross-sectional shape as appropriate. It may have any desired cross-sectional shape.

In addition, in this specification, "the tip part of a core shaft" especially refers to the area|region between the proximal end of a tip fixing part and the tip of a main body part.

Hereinafter, first and second embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited only to the embodiments shown in the drawings.

[First embodiment]
FIG. 1 is a schematic side view showing a first embodiment of the present invention. As shown in FIG. 1, the guide wire 1 is roughly composed of a core shaft 11, a distal end fixing portion 21, a first inner coil body 31, and an outer coil body 41.

The core shaft 11 has, for example, a tip portion 11A and a main body portion 11B. The tip portion 11A has a non-perfect circular cross-sectional shape. Specifically, the cross-sectional shape of the tip 11A is, for example, rectangular (see tip 11A1 in FIG. 2A), square (see tip 11A2 in FIG. 2B), or elliptical (long circle) (see tip 11A2 in FIG. 2C tip 11A3), a rectangular or square shape with rounded corners (not shown), and a combination of these shapes along the long axis direction (not shown). .

Among these, the cross-sectional shape of the core shaft tip 11A is preferably a rectangular shape such as a rectangular shape or a square shape (see FIGS. 2A and 2B), or an elliptical shape (see FIG. 2C). Thereby, it is possible to know in advance the direction in which the guide wire 1 is likely to bend, and for example, it is possible to improve the operability when the guide wire 1 moves forward in a blood vessel.

As a method for forming the core shaft tip portion 11A, for example, a method of press molding using a mold, a method of molding by cutting, etc. can be adopted.

The main body portion 11B is a portion that has a perfect circular cross-sectional shape at least in a portion continuous with the distal end portion 11A and extends toward the proximal end side. Specifically, the main body portion 11B includes, for example, an enlarged diameter portion whose distal end is continuous with the proximal end of the distal end portion 11A and whose diameter increases gradually or stepwise toward the proximal end, and whose distal end is connected to the enlarged diameter portion. It can be configured by a large diameter portion having a constant outer diameter, which is continuous with the proximal end and extends toward the proximal end.

In this embodiment, an enlarged diameter part 11B1 (tapered part) whose distal end is continuous with the proximal end of the distal end part 11A and gradually increases in diameter toward the proximal end, and The core shaft 11 is illustrated as having a large diameter portion 11B2 having a constant outer diameter and extending toward the end.

The material constituting the core shaft 11 may be, for example, stainless steel such as SUS304 or superelastic material such as Ni-Ti alloy, from the viewpoint of improving the flexibility of the guide wire 1 and providing antithrombotic properties and biocompatibility. Alloy etc. can be adopted.

The dimensions of the core shaft 11 in the longitudinal direction are usually 1,800 to 3,000 mm in total length and 5 mm to 100 mm in the tip portion 11A. The outer diameter of the core shaft 11 is usually 0.03 mm to 0.1 mm at the tip portion 11A and 0.25 mm to 0.46 mm at the large diameter portion 11B2.

The tip fixing portion 21 is a portion where at least the tip of the core shaft 11 and the tip of the outer coil body 41 (described later) are fixed. Specifically, the distal end fixing portion 21 can be formed, for example, so that the distal end thereof has a substantially hemispherical shape that is convexly curved toward the distal end side.

As a method for forming the tip fixing portion 21, for example, a method of heating and melting the tip of the core shaft tip 11A and/or the tip of the outer coil body 41, a method of joining by brazing using a brazing material, etc. are adopted. can do. Examples of the brazing material include metal brazing materials such as Sn--Pb alloy, Pb--Ag alloy, Sn--Ag alloy, and Au--Sn alloy.

The first inner coil body 31 is a helical member (coil) that is continuously wound from the distal end portion 11A of the core shaft 11 to the main body portion 11B so as to be in close contact with the core shaft 11.

Note that the portion of the main body portion 11B having a perfect circular cross-sectional shape is at least the portion that is continuous with the distal end portion 11A and around which the first inner coil body 31 is wound, and the portion on the proximal side thereof is It may be circular or have any desired cross-sectional shape.

The manner in which the first inner coil body 31 is wound around the core shaft 11 is not particularly limited as long as the first inner coil body 31 and the core shaft 11 are in close contact with each other. It is preferable that adjacent strands 31a are also in close contact with each other. Thereby, torque transmittance (ease of transmitting rotational force from the proximal end to the distal end of the guide wire) can be further enhanced.

Examples of the form of the first inner coil body 31 include a coil formed by winding the wire 31a (see FIG. 1), and a coil formed by performing slit processing etc. on a cylindrical member. (not shown), etc. When using the wire 31a for the first inner coil body 31, the wire 31a can be one or more solid 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.

Here, it is preferable that the first inner coil body 31 is composed of a multi-thread coil. Specifically, such a first inner coil body 31 includes, for example, one using a plurality of solid wires, one using a plurality of stranded wires, or one using one or more of each of a single wire and a stranded wire. Examples include things. Thereby, the torque transmittance can be further improved, and the generation of splashes can be further reduced.

The diameter of the wire 31a (single wire or stranded wire) constituting the first inner coil body 31 is usually 0.01 to 0.10 mm.

The material of the wire 31a constituting the first inner coil body 31 is, for example, stainless steel such as SUS316, from the viewpoint of imparting flexibility to the guide wire 1 and imparting antithrombotic properties and biocompatibility; Superelastic alloys such as Ni--Ti alloys; radiopaque metals such as platinum and tungsten can be used.

The first inner coil body 31 has its distal end located at, for example, the proximal end of the distal end fixing portion 21 or on the outer circumferential surface of the distal end portion 11A of the core shaft (midway in the longitudinal direction of the distal end portion 11A of the core shaft). However, it can be arranged such that the base end is located on the outer circumferential surface of the enlarged diameter portion 11B1 or the large diameter portion 11B2 of the core shaft 11.

The first inner coil body 31 is fixed to at least one of the proximal end of the distal end fixing part 21 and the outer periphery of the distal end part 11A of the core shaft, and the outer periphery of the enlarged diameter part 11B1 and/or the large diameter part 11B2 of the core shaft. has been done. The part where the first inner coil body 31 and the core shaft 11 etc. are fixed may be a part of the part where the two come into contact, or may be the entire part.

In this embodiment, the first inner coil body 31 is illustrated in which the distal end is located at the proximal end of the distal end fixing portion 21 and the proximal end is located on the outer circumferential surface of the enlarged diameter portion 11B1 of the core shaft. In addition, in this embodiment, the first inner coil body 31 is fixed at two locations: the proximal end of the distal end fixing part 21 and the outer periphery of the expanded diameter part 11B1 of the core shaft (see fixed part S31a and fixed part S31b in FIG. 1). has been done.

As a method of fixing the first inner coil body 31 and the tip fixing part 21, for example, a fixing method similar to that described as the fixing method of the core shaft 11 and the tip fixing part 21 can be adopted. As a method of fixing the first inner coil body 31 and the core shaft 11, for example, a method of joining by brazing using a brazing material, etc. can be adopted. As the brazing material, the same material as that used in forming the tip fixing portion 21 can be employed.

The outer coil body 41 is a spiral member (coil) wound so as to cover the first inner coil body 31 . As the form and wire of the outer coil body 41, for example, the same ones as those explained as the first inner coil body 31 can be adopted.

For example, the outer coil body 41 has its distal end located at the proximal end of the distal end fixing portion 21, and its proximal end located on the outer circumferential surface of the enlarged diameter portion 11B1 of the core shaft (see FIG. 1) or on the outer circumferential surface of the large diameter portion 11B2. (not shown). In this embodiment, the outer coil body 41 is fixed at two locations: the base end of the distal end fixing part 21 and the outer periphery of the enlarged diameter part 11B1 of the core shaft (see fixed part S41a and fixed part S41b in FIG. 1).

Examples of the method of fixing the outer coil body 41 and the tip fixing part 21 and the fixing method of the outer coil body 41 and the core shaft 11 include a method of fixing the first inner coil body 31 and the tip fixing part 21, respectively; A fixing method similar to that described above for fixing the first inner coil body 31 and the core shaft 11 can be employed.

Next, how the guide wire 1 is used will be explained. Here, a procedure will be described in which the guide wire 1 is used to penetrate a chronic complete occlusion (CTO) (hereinafter also referred to as a "treatment site") with its distal end.

First, the guide wire 1 is inserted into a blood vessel from its tip, and the tip is pushed to the treatment site while manipulating the portion of the guide wire 1 that is exposed outside the body. Next, the tip of the guide wire 1 is punctured into the treatment site. At this time, for example, the guide wire 1 may be rotated while pressing the tip against the treatment site. Specifically, the operator grasps the proximal end of the guide wire 1 and performs a rotation operation. At this time, according to the guide wire 1, the rotational force applied to the proximal end (proximal end) can be reliably transmitted to the distal end, so even if resistance is encountered from the treatment site, splashes will not occur. It is possible to easily penetrate the treatment site by the desired rotation while suppressing the turbulence.

After penetrating the treatment site using the guide wire 1, a medical device such as a balloon catheter or a stent (not shown) is inserted into the guide wire 1, and the medical device is passed along the guide wire 1 to the treatment site. Various treatments may be performed by transporting the object. After the above treatment is completed, the guide wire 1 and the like are removed from the body, thereby completing the series of procedures.

As described above, since the guide wire 1 has the above-mentioned configuration, it is possible to reliably transmit the rotational force applied to the proximal end (proximal end) to the distal end, and to maintain the flexibility of the distal end while preventing the spring from spreading. Occurrence can be prevented. As a result, damage to the inner walls of blood vessels can be suppressed and smooth treatment can be performed.

[Second embodiment]
3 and 4 are schematic diagrams showing a second embodiment of the invention. As shown in FIGS. 3 and 4, the guide wire 2 schematically includes a core shaft 11, a distal end fixing portion 21, a first inner coil body 31, a second inner coil body 32, and an outer side. It is constituted by a coil body 41. The guide wire 2 differs from the first embodiment in that it includes a second inner coil body 32. Note that the configuration other than the configuration of the second inner coil body 32 shown below is the same as that of the first embodiment, so the same parts are given the same reference numerals and detailed explanation thereof will be omitted. Further, since the manner of use of the guide wire 2 is the same as that in the first embodiment, detailed explanation thereof will be omitted.

The second inner coil body 32 is a helical member (coil) that is in close contact with the first inner coil body 31 and is wound in a direction opposite to the winding direction of the first inner coil body 31 . That is, the first inner coil body 31 and the second inner coil body 32 have a relationship in which one is S-twisted and the other is Z-twisted.

The second inner coil body 32 can be formed into a coil shape by winding the wire 32a (see FIG. 3), or a cylindrical member formed into a coil shape by performing slit processing or the like. (not shown), etc. When using the wire 32a for the second inner coil body 32, the same wire as the wire 31a described in connection with the first inner coil body 31 can be used as the wire 32a, for example.

For example, the second inner coil body 32 has a distal end located on the proximal end of the distal end fixing portion 21 or the outer periphery of the first inner coil body 31 at the distal end portion 11A of the core shaft, and a proximal end thereof It can be arranged so as to be located on the outer circumference of the first inner coil body 31 in the enlarged diameter portion 11B1 of the shaft, or on the outer circumferential surface of the enlarged diameter portion 11B1 or the large diameter portion 11B2 of the core shaft.

The second inner coil body 32 is attached to at least one of the proximal end of the distal end fixing portion 21 and the outer periphery of the first inner coil body 31, as well as the outer periphery of the first inner coil body 31 or the enlarged diameter portion of the core shaft. 11B1 or the outer periphery of the large diameter portion 11B2. The portion where the second inner coil body 32 and the first inner coil body 31 etc. are fixed may be a part of the area where the two come into contact, or may be the entire area.

In the present embodiment, the second inner coil body 32 is exemplified, the distal end of which is located at the proximal end of the distal end fixing portion 21, and the proximal end of which is located on the outer periphery of the first inner coil body 31 on the enlarged diameter portion 11B1. There is. In addition, in this embodiment, the second inner coil body 32 is fixed at two places, the proximal end of the distal end fixing part 21 and the outer periphery of the first inner coil body 31 (fixed part S32a and fixed part S32a in FIG. 3). (See section S32b).

The method of fixing the second inner coil body 32 and the tip fixing portion 21 and the method of fixing the second inner coil body 32 and the core shaft 11 are as follows: The same methods as those exemplified as the fixing method and the fixing method of the first inner coil body 31 and the core shaft 11 can be adopted.

As described above, since the guide wire 2 has the above configuration, when the guide wire 2 is rotated, the wire 31a of the first inner coil body 31 and the wire 32a of the second inner coil body 32 are connected to each other. The directions of the applied axial forces can be made opposite, so that no matter which direction the guide wire 2 is rotated, either the adjacent strands 31a, 31a or the adjacent strands 32a, 32a will be at the tip of the core shaft. Since the portion 11A is tightened, torque transmission performance can be improved.

The present invention is not limited to the configuration of the embodiments described above, but is indicated by the scope of the claims, and is intended to include all changes within the scope and meaning equivalent to the scope of the claims. be done.

For example, in the first embodiment described above, the guide wire 1 has been described in which the distal end of the first inner coil body 31 is joined to the distal end fixing part 21, but the distal end of the first inner coil body 31m1 is connected to the distal end of the core shaft. The guide wire 1m1 may be fixed to the outer periphery of the guide wire 11A (see joint portion S31am1 in FIG. 5A). When such a first inner coil body is provided and a second inner coil body is provided, the tip of the second inner coil body may be fixed to the tip fixing part, and the tip of the core shaft may be fixed to the tip fixing part. It may be fixed to the outer periphery or may be fixed to the outer periphery of the first inner coil body.

Furthermore, in the embodiments described above, the guide wires 1 and 2 were described in which the main body portion 11B of the core shaft was constituted by the enlarged diameter portion 11B1 and the large diameter portion 11B2. It is sufficient that the cross-sectional shape of the portion is a perfect circle and extends toward the proximal end, for example, a core shaft in which the main body portion 11Bm2 consists only of an enlarged diameter portion 11B1m2 whose diameter gradually increases toward the proximal end. A guide wire 1 m2 having a diameter of 11 m2 (see FIG. 5B), a guide wire 1 m3 having a core shaft 11 m3 having an enlarged diameter portion 11B1m3 in which the main body portion 11Bm3 increases in diameter stepwise toward the proximal end (see FIG. 5C), etc. It may be. In the guide wire 1m3, the first inner coil body 31m3 may be fixed, for example, to the proximal end of the distal end fixing part 21 and the outer periphery of the expanded diameter part 11B1m3 of the core shaft (see fixed part S31am3 and fixed part S31bm3).

In the above-described embodiment, when the core shaft tip 11A has a shape based on a rectangular shape such as a rectangular shape with rounded corners, the first inner coil body 31 is a core shaft tip. At the corner portion 11A, it is conceivable that the rigidity of the first inner coil body 31 causes the first inner coil body 31 to come out of close contact with the tip portion 11A of the core shaft. In the present invention, "close contact" means that the first inner coil body is in close contact with the entire circumference of the core shaft tip, but the first inner coil body is in close contact with each other in one turn. The distal end portion of the core shaft may be contacted at least once or more.

Furthermore, in the embodiment described above, it has been explained that the portion of the main body portion 11B of the core shaft that is continuous with the tip portion 11A and around which the first inner coil body 31 is wound is “perfectly circular.” This does not exclude the occurrence of errors in shape due to manufacturing errors, etc.

1, 2 Guide wire 11 Core shaft 11A Tip of core shaft 11B Main body (main body of core shaft)
21 Tip fixing part 31 First inner coil body 32 Second inner coil body 41 Outer coil body

Claims (4)

A core shaft having a distal end portion having a non-perfect circular cross-sectional shape, and a main body portion having a true circular cross-sectional shape at least in a portion continuous with the distal end portion and extending toward the proximal end side;
a first inner coil body wound continuously from the tip of the core shaft to the main body and in close contact with the core shaft;
an outer coil body wound to cover the first inner coil body;
a tip fixing portion to which at least the tip of the core shaft and the tip of the outer coil body are fixed ;
The distal end of the first inner coil body is a guide located at the proximal end of the distal end fixing portion, or on the proximal side of the proximal end of the distal fixing portion and distal side of the distal end of the main body portion. wire. The guide wire according to claim 1, wherein the cross-sectional shape of the distal end portion is rectangular or oval. The guide wire according to claim 1 or 2, wherein the first inner coil body is composed of a multi-thread coil. Claims 1 to 3 further comprising a second inner coil body that is in close contact with the first inner coil body and is wound in a direction opposite to the winding direction of the first inner coil body. The guide wire according to any one of the items.

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