JP2018192058A - Medical guide wire - Google Patents

Abstract

To provide a guide wire excellent in torque transmission property relative to prior ones.SOLUTION: A guide wire comprises: a core wire 10; a left-handed outside coil spring 20 which is attached to an outer periphery of a distal end side small diameter part 13 of the core wire 10 and which comprises a tip side small diameter part 21, a taper part 22 and a rear end side large diameter part 23; and a right-handed inside coil spring 30 which is attached to an outer periphery of the distal end side small diameter part 13 of the core wire 10 in the outside coil spring 20. The tip part of the outside coil spring 20 and tip part of the inside coil spring 30 are fastened to the core wire 10 on a first fastening part 51 formed of an Au-Sn based solder, the rear end part of the inside coil spring 30 is fastened to the core wire 10 on a second fastening part 52 formed of the Au-Sn based solder, and the rear end part of the outside coil spring 20 is fastened to the core wire 10 on a third fastening part 53 formed of an Ag-Sn based solder.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a medical guide wire excellent in torque transmission.

  As a guide wire for guiding a medical device such as a catheter to a predetermined position in a body cavity such as a blood vessel, the outer diameter of the distal end portion of the core wire is made smaller than the outer diameter of the proximal end portion. A medical guide wire is known in which a coil spring is attached to a distal end portion (distal end side small-diameter portion) to improve flexibility of the distal end portion (for example, Patent Document 1 below). reference).

The medical guide wire as described above is required to transmit the rotational torque on the proximal end side to the distal end side, that is, to have good torque transmission.
In order to improve torque transmission, a guide wire having a double coil structure in which coil springs are double-mounted on the distal end portion of a core wire has been introduced (for example, see Patent Document 2 below).

The guide wire described in Patent Document 2 includes a core wire, an inner coil spring that covers the core wire, and an outer coil spring that covers the inner coil spring.
However, in this guide wire, the proximal end of the inner coil spring is fixed to the core wire, but the distal end of the inner coil spring is not fixed to either the core wire or the outer coil spring.

  For this reason, depending on the guide wire described in Patent Document 2, it is not possible to sufficiently achieve the effect of improving torque transmission by mounting the inner coil spring.

  By the way, when a guide wire is inserted into a microchannel in a CTO (chronic complete occlusion) lesion, the operator performs bending (shaping operation) of the distal end portion thereof.

  This shaping operation greatly affects the operability of the guide wire in the microchannel. From the viewpoint of reducing frictional resistance in the microchannel, the shaping length (bending length of the tip) needs to be as short as possible, specifically 0.7 mm or less.

JP 2003-299739 A JP 2014-1000026 A

The present invention has been made based on the above situation.
An object of the present invention is to provide a guide wire that is superior in torque transmission than conventional ones.
Another object of the present invention is to provide a medical guide wire excellent in operability in a microchannel of a CTO lesion.

(1) The medical guidewire of the present invention includes a core wire having a distal end side small diameter portion and a proximal end side large diameter portion having a larger outer diameter than the distal end side small diameter portion;
Attached to the outer periphery of the distal end side small diameter portion of the core wire along the axial direction, the tip side small diameter portion, the rear end side large diameter portion having a coil outer diameter larger than the tip side small diameter portion, and the tip side small diameter An outer coil spring fixed to the core wire at least at the front end portion and the rear end portion, and a taper portion located between the portion and the rear end side large diameter portion,
An inner coil spring which is attached along the axial direction to the outer periphery of the small diameter portion of the distal end side of the core wire inside the outer coil spring, and which is fixed to the core wire at least at the front end portion and the rear end portion. ,
The outer coil spring has a length of 5 to 100 mm at the distal end side small diameter portion and a coil outer diameter of 0.012 inch or less,
The distal end portion of the outer coil spring and the distal end portion of the inner coil spring are fixed to the core wire in a first fixing portion by solder,
The rear end portion of the inner coil spring is fixed to the core wire at a second fixing portion by solder,
The rear end portion of the outer coil spring is fixed to the core wire at a third fixing portion by solder,
The length of the first fixing portion (length in the axial direction) is 0.1 to 0.5 mm,
The winding direction of the outer coil spring and the winding direction of the inner coil spring are opposite to each other.

  According to the medical guide wire having such a configuration, the distal end portion of the outer coil spring and the distal end portion of the inner coil spring are fixed to the core wire at the first fixing portion, and the rear end portion of the inner coil spring is fixed at the second fixing portion. Since the rear end portion of the outer coil spring is fixed to the core wire at the third fixing portion, the outer coil spring and the inner coil spring are fixed to the core wire at the respective end portions, respectively. Since they are fixed to each other at the front end portions, the integrity (interlocking) of the core wire, the inner coil spring, and the outer coil spring can be improved, thereby sufficiently improving torque transmission. Can do.

  Furthermore, the winding direction of the outer coil spring and the winding direction of the inner coil spring are opposite to each other, so that the outer coil spring is rotated in the direction of tightening (clockwise or counterclockwise) on the proximal end side (hand side). The inner coil spring is opened when the outer coil spring is rotated, and the inner coil spring is tightened when the outer coil spring is rotated in the opening direction (counterclockwise or clockwise). There is no great difference in torque transmission performance between when rotational torque is applied, and any rotational torque in any rotational direction can be reliably transmitted to the distal end side.

(2) In the medical guide wire of the present invention, it is preferable that the tapered portion of the outer coil spring is fixed to the core wire at a fourth fixing portion by solder.

  According to the medical guide wire having such a configuration, the integrity (interlocking) of the core wire, the inner coil spring, and the outer coil spring can be further improved, and the rotational torque from the hand side is tapered. Therefore, the torque transmission can be further improved.

Here, when the inner coil spring is located inside the distal-side small-diameter portion of the outer coil spring, the fourth fixing portion is formed on the rear end side of the second fixing portion.
Further, when the rear end portion of the inner coil spring is positioned inside the rear end side large diameter portion of the outer coil spring, the fourth fixing portion is formed on the front end side of the second fixing portion, and the fourth In the fixing portion, the middle portion of the inner coil spring is fixed to the core wire together with the tapered portion of the outer coil spring.
When the rear end portion of the inner coil spring is located inside the tapered portion of the outer coil spring, the fourth fixing portion coincides with the second fixing portion.

(3) In the medical guidewire of the present invention, the intermediate portion of the outer coil spring is fixed to the core wire together with the rear end portion of the inner coil spring in the second fixing portion by solder. preferable.

  According to the medical guide wire having such a configuration, the distal end portion of the outer coil spring and the distal end portion of the inner coil spring are fixed to the core wire at the first fixing portion, and the intermediate portion of the outer coil spring and the inner coil spring are When the rear end portion is fixed to the core wire at the second fixing portion, the inner coil spring is fixed to both the core wire and the outer coil spring at both ends thereof, and the core wire, the inner coil spring, Since the integrity (interlocking) with the outer coil spring can be further improved, the torque transmission can be further improved.

(4) In the medical guidewire of the present invention, it is preferable that the first fixing portion is made of Au—Sn solder.

According to the medical guide wire having such a configuration, Au—Sn solder is used as the solder constituting the first fixing portion for fixing the tip portion of the outer coil spring and the tip portion of the inner coil spring to the core wire. Therefore, although the length of the first fixing portion is as short as 0.1 to 0.5 mm (the fixing region by the solder is narrow), the fixing strength of the outer coil spring and the inner coil spring to the core wire is sufficiently high. can do. And since the length of a 1st adhering part is as short as 0.1-0.5 mm, shaping length (bending length of a front-end | tip) can be shortened (it shall be 0.7 mm or less), As a result, for example, The frictional resistance can be sufficiently reduced during operation in the microchannel.
In addition, treatment in a narrow region that cannot be performed using a conventional guide wire is also possible.

(5) In the medical guide wire of the present invention, it is preferable that the winding direction of the outer coil spring is the left direction.

  As described above, according to the guide wire of the present invention, there is no significant difference in torque transmission between when the rotational torque is applied clockwise and when the rotational torque is applied counterclockwise. Torque transmission when rotating in the direction in which the coil spring is tightened (direction in which the inner coil spring opens) is superior to torque transmission in the direction in which the outer coil spring is rotated (direction in which the inner coil spring is tightened) It will be.

  Further, according to the present inventors' confirmation, when the tip of the guide wire is trapped, the operator first tends to apply the rotational torque in the clockwise direction. Here, when the rotational torque is applied clockwise, the coil spring whose winding direction is the left direction is tightened, and the coil spring whose winding direction is the right direction is opened.

  Therefore, according to the guide wire of the present invention in which the winding direction of the outer coil spring is the left direction, the outer coil spring is tightened by applying the rotational torque clockwise as the initial movement according to the above tendency. Torque transmission performance (torque transmission performance when the tip is trapped) superior to a guide wire whose direction is rightward can be exhibited.

(6) In the medical guidewire of the present invention, it is preferable that the second fixing portion is made of Au—Sn solder.
By configuring the second fixing portion with the Au—Sn solder, the fixing strength of the outer coil spring and the inner coil spring to the core wire in the medical guide wire of the present invention can be further increased.

(7) In the medical guidewire of (2), it is preferable that the second fixing portion and the fourth fixing portion are made of Au—Sn solder.
By configuring the second fixing portion and the fourth fixing portion with Au-Sn solder, the strength of fixing the outer coil spring and the inner coil spring to the core wire in the medical guide wire of (2) is further increased. Can do.

(8) In the medical guidewire of the present invention, it is preferable that the outer diameter of the coil at the rear end side large diameter portion of the outer coil spring is 0.014 inch or more.
As a result, torque transmission can be further improved, and the bending rigidity of the guide wire (push transmission at the time of insertion / delivery performance of the device after insertion) can be improved.

(9) In the medical guidewire of the present invention, the first fixing portion includes an inner layer portion made of Au-Sn solder covering the distal end of the core wire,
It is preferable to include an outer layer portion made of Ag—Sn solder that fixes the distal end of the core wire and the tip portion of the outer coil spring so as to cover the inner layer portion.

  According to the medical guide wire having such a configuration, the inner layer portion of the solder (the outer periphery of the distal end of the core wire) constituting the first fixing portion that fixes the tip portion of the outer coil spring and the tip portion of the inner coil spring to the core wire. Since the Au—Sn solder is used for the portion in contact with the above (4), the same effect as the medical guide wire (4) can be obtained.

(10) In the medical guidewire according to (9), the outer layer portion of the first fixing portion covers the inner layer portion of the distal end of the core wire and the tip portion of the inner coil spring. It is preferable to adhere to.

(11) In the medical guidewire according to (9), it is preferable that the inner layer portion of the first fixing portion fixes the distal end of the core wire and the tip portion of the inner coil spring. .

  The medical guide wire of the present invention is superior in torque transmission performance, particularly in the case where the tip is trapped, as compared with the conventional guide wire.

It is explanatory drawing which shows the external appearance of the guide wire which concerns on 1st Embodiment of this invention. It is sectional drawing (AA sectional drawing) of the guide wire shown in FIG. It is sectional drawing which shows the distal end side part of the guide wire shown in FIG. It is sectional drawing which shows the distal end side part of the guide wire which concerns on 2nd Embodiment of this invention. It is explanatory drawing which shows the outline of the apparatus used for the evaluation test (trap test) of torque transferability. It is a photograph which shows the state by which the front-end | tip of a guide wire was pinched | interposed into two silicone sheets in the torque transmission evaluation test (trap test). It is sectional drawing which shows the modification of a 1st adhering part. It is sectional drawing which shows the modification of a 1st adhering part.

<First Embodiment>
The guide wire shown in FIGS. 1 to 3 includes a core wire 10, an outer coil spring 20, and an inner coil spring 30.

The core wire 10 has a distal end side small diameter portion 11, a tapered portion 12 that continuously expands toward the proximal end side, and a proximal end side large diameter portion 13.
The distal end side small diameter portion 11 of the core wire 10 includes a first small diameter portion 111, a taper portion 112, and a second small diameter portion 113.

The core wire 10 is integrally formed of a wire having a substantially circular cross section.
The material of the core wire 10 is not particularly limited, and examples thereof include metals such as stainless steel (for example, SUS316, SUS304), gold, platinum, aluminum, tungsten, tantalum, and alloys thereof. Then, it is comprised, for example with stainless steel.

The total length of the core wire 10 varies depending on the purpose of use and is not particularly limited, but is, for example, 1000 to 3000 mm, and preferably 1800 to 2000 mm.
Moreover, it is preferable that it is 0.014 inch (0.356 mm) or more as an outer diameter of the proximal end side large diameter part 13 of the core wire 10, and it will be 0.014 inch if a suitable example is shown.

The length of the distal end side small diameter portion 11 of the core wire 10 is, for example, 5 to 30 mm, preferably 10 to 20 mm, and 15 mm if a suitable example is shown.
The outer diameter of the first small diameter part 111 of the distal end side small diameter part 11 is, for example, about 1/20 to 1/5 of the outer diameter of the proximal end side large diameter part 13.
The outer diameter of the second small diameter portion 113 of the distal end side small diameter portion 11 is, for example, about 1/10 to 3/4 of the outer diameter of the proximal end side large diameter portion 13.

A water repellent resin layer (not shown) is formed on the outer peripheral surface of the core wire 10.
As the resin constituting the water-repellent resin layer, any resin that is used for medical purposes and has water repellency can be used, and suitable resins include fluorine-based resins such as PTFE.

The outer coil spring 20 constituting the guide wire is formed by winding a single wire in the left direction, and is attached to the outer periphery of the distal end side small diameter portion 11 of the core wire 10 along the axial direction.
The outer coil spring 20 includes a front end side small diameter portion 21, a tapered portion 22, and a rear end side large diameter portion 23.

The length of the outer coil spring 20 is, for example, 30 to 800 mm, preferably 100 to 200 mm, and 165 mm if a suitable example is shown.
The length of the distal end side small diameter portion 21 is 5 to 100 mm, preferably 10 to 70 mm, and 38.5 mm if a suitable example is shown.
When the length of the distal end side small diameter portion 21 is 5 mm or more, the distal end side small diameter portion 21 can be inserted into most microchannels.
When the length of the front end side small diameter portion 21 is 100 mm or less, it is possible to sufficiently secure the length of the rear end side large diameter portion 23 that contributes to improvement in bending rigidity and torque transmission.
The length of the taper part 22 shall be 0.5-10 mm, for example, and will be 1.5 mm if a suitable example is shown.
The length of the rear end side large diameter portion 23 is, for example, 85 to 154.5 mm, and 125 mm if a suitable example is shown.

  The outer diameter of the coil at the distal end side small diameter portion 21 of the outer coil spring 20 is usually 0.012 inch (0.305 mm) or less, preferably 0.006 to 0.011 inch, 0.011 if a suitable example is shown. Inch (0.279 mm).

  When the coil outer diameter of the distal-side small diameter portion 21 is 0.012 inches or less, the operability when accessing the microchannel (for example, lubricity in the microchannel) is excellent.

  The outer diameter of the coil at the rear end side large diameter portion 23 of the outer coil spring 20 is preferably 0.014 inch (0.356 mm) or more, and 0.014 inch is shown as a suitable example.

When the coil outer diameter of the rear end side large-diameter portion 23 is 0.014 inches or more, sufficient bending rigidity (push transmission at the time of insertion / delivery performance of the device after insertion) is imparted to the guide wire.
The ratio of the outer diameter of the coil between the rear end side large diameter portion 23 and the front end side small diameter portion 21 is preferably 1.1 to 2.3.

Although the outer diameter of the wire which comprises the outer side coil spring 20 is not specifically limited, Preferably it is 30-90 micrometers, and if it shows a suitable example, it is 50 micrometers.
The material of the outer coil spring 20 is a material (X-ray opaque) having good contrast properties with respect to X-rays, such as platinum, platinum alloy, gold, gold-copper alloy, tungsten, tantalum, palladium alloy (for example, Pd / Re alloy). Substance).

The winding direction of the outer coil spring 20 is the left direction (left winding / S winding).
The outer coil spring 20 whose winding direction is the left direction is tightened when it is rotated clockwise, and is opened when it is rotated counterclockwise.
Therefore, when the outer coil spring 20 is rotated clockwise, rotational torque is easily transmitted.

1 to 3, the wires constituting the outer coil spring 20 are shown in close contact with each other (coil pitch = coil wire diameter), but even if a gap is formed between the wires in the entire length or in part. Good.
Here, the coil pitch of the outer coil spring 20 is preferably 1.0 to 1.5 times the coil wire diameter.

  The inner coil spring 30 constituting the guide wire is configured by winding one wire in the right direction (the direction opposite to the winding direction of the outer coil spring 20). Inside, it is mounted along the axial direction on the outer periphery of the distal end portion of the small-diameter portion 11 on the distal end side of the core wire 10.

  The length of the inner coil spring 30 is, for example, 5 to 60 mm, preferably 10 to 40 mm, and 25 mm if a suitable example is shown.

  The coil outer diameter of the inner coil spring 30 is, for example, 0.008 inch (0.203 mm) or less, preferably 0.006 inch (0.152 mm) or less, and 0.0055 inch if a suitable example is shown.

Although the outer diameter of the wire which comprises the inner side coil spring 30 is not specifically limited, Preferably it is 10-40 micrometers, and if it shows a suitable example, it will be 30 micrometers.
The material of the inner coil spring 30 is a material (X-ray opaque material) having good contrast with respect to X-rays such as platinum, platinum alloy (for example, Pt / W alloy), gold, gold-copper alloy, tungsten, tantalum, and palladium. ).

The winding direction of the inner coil spring 30 is the right direction (right winding / Z winding).
The inner coil spring 30 whose winding direction is the right direction is tightened when it is rotated counterclockwise, and is opened when it is rotated clockwise.
Therefore, when the inner coil spring 30 is rotated counterclockwise, rotational torque is easily transmitted.

  In the guide wire of this embodiment, each of the outer coil spring 20 and the inner coil spring 30 is fixed to the outer periphery of the distal end side small diameter portion 11 of the core wire 10 by solder.

The front end portion of the outer coil spring 20 and the front end portion of the inner coil spring 30 are fixed to the outer periphery of the small-diameter portion 11 on the distal end side of the core wire 10 at a first fixing portion 51 made of Au—Sn solder.
That is, the Au—Sn solder constituting the first fixing portion 51 penetrates into the inside of the tip portion of the outer coil spring 20 (tip-side small-diameter portion 21) and inside the tip portion of the inner coil spring 30, and the core wire 10 ( By making contact with the outer periphery of the distal end side small diameter portion 11), the distal end portion of the outer coil spring 20 and the distal end portion of the inner coil spring 30 are fixed to the distal end of the core wire 10 (distal end side small diameter portion 11). .
Thereby, the tip of the inner coil spring 30 is firmly fixed to both the core wire 10 and the outer coil spring 20.

As shown in FIGS. 2 and 3, a substantially hemispherical tip that is a part of the first fixing portion 51 is formed by the Au—Sn solder that has not penetrated into the tip of the outer coil spring 20. ing.
That is, the first adhering portion 51 (rigid portion) is formed by the Au—Sn solder penetrating into the coil springs (the outer coil spring 20 and the inner coil spring 30) and the tip formed by the Au—Sn solder. Is formed.

The rear end portion of the inner coil spring 30 is fixed to the outer periphery of the distal end side small diameter portion 11 of the core wire 10 at the second fixing portion 52 made of Au—Sn solder.
That is, the Au—Sn solder constituting the second fixing portion 52 penetrates into the rear end portion of the inner coil spring 30 and comes into contact with the outer periphery of the core wire 10 (distal end side small diameter portion 11). The rear end portion of the coil spring 30 is fixed to the core wire 10 (distal end side small diameter portion 11).

The rear end portion of the outer coil spring 20 is fixed to the outer periphery of the distal end side small-diameter portion 11 of the core wire 10 at the third fixing portion 53 made of Ag—Sn solder.
That is, the Ag—Sn solder constituting the third fixing portion 53 penetrates into the rear end portion of the outer coil spring 20 (the rear end portion of the rear end side large diameter portion 23), and the core wire 10 (distal end side). By contacting the outer periphery of the small diameter portion 11), the rear end portion of the outer coil spring 20 is fixed to the core wire 10 (distal end side small diameter portion 11).

  In the distal end side small diameter portion 11 of the core wire 10, the outer diameter of the portion to which the rear end side large diameter portion 23 of the outer coil spring 20 is fixed is the portion to which the tip side small diameter portion 21 of the outer coil spring 20 is fixed (distal). Since it is larger than the outer diameter of the edge (relatively large fixing area), it is possible to use an Ag—Sn based solder having a small fixing strength compared to the Au—Sn based solder.

  The tapered portion 22 of the outer coil spring 20 is fixed to the outer periphery of the distal end side small diameter portion 11 of the core wire 10 at the fourth fixing portion 54 made of Au—Sn solder.

The length of the 1st adhering part 51 shall be 0.1-0.5 mm.
When this length is less than 0.1 mm, it is not possible to sufficiently secure the fixing strength between the outer coil spring and the inner coil spring with respect to the core wire and the fixing strength between the outer coil spring and the inner coil spring.
On the other hand, when the length of the tip rigid portion exceeds 0.5 mm, the shaping length becomes long (cannot be 0.7 mm or less).

  The Au—Sn solder constituting the first fixing part 51, the second fixing part 52, and the fourth fixing part 54 is a binary or multi-component solder containing Au and Sn as main components. One made of an alloy of 75 to 85% by weight of Au and 25 to 15% by weight of Sn (Au80Sn20 eutectic solder as a suitable example), one made of an alloy of 5 to 15% by weight of Au and 95 to 85% by weight of Sn (suitable) An example is Au10Sn90 eutectic solder).

By fixing the constituent material of the core wire 10 (for example, stainless steel) and the constituent material of the outer coil spring 20 and the inner coil spring 30 (for example, the X-ray opaque material described above) using Au—Sn solder, Higher fixing force (tensile strength) can be obtained as compared with the case of fixing with Ag-Sn solder (Ag3.5Sn96.5).
For this reason, even when the length of the tip rigid portion is as short as 0.1 to 0.5 mm, the fixing strength of the outer coil spring 20 to the core wire 10 can be sufficiently increased.
In addition, Au—Sn solder is superior in contrast to Ag—Sn solder.
Furthermore, Au—Sn solder is superior in corrosion resistance to blood and body fluids than Ag—Sn solder.

The guide wire of this embodiment is filled with a hardened resin (not shown) in the inside of the outer coil spring 20 (inner space where the inner coil spring 30 is not mounted and the solder does not permeate). The outer periphery of the outer coil spring 20 and the tip are covered by the resin layer.
And the hydrophilic resin layer which is not illustrated is laminated | stacked and formed on the surface of this resin layer.

  By filling the inside of the outer coil spring 20 with the cured resin, the integrity (interlocking) between the core wire 10 and the outer coil spring 20 is further improved. Thereby, the torque transmission property of a guide wire further improves, and the rotational torque transmitted from the proximal end side large diameter part 13 of the core wire 10 is reliably transmitted to the distal end of a guide wire.

  In addition, since the hydrophilic resin layer is formed on the outer periphery of the outer coil spring 20 via the resin layer (undercoat layer), the hydrophilic resin layer is firmly fixed, and the lubricity by the hydrophilic resin is stabilized. It can be expressed in an experimental manner.

Here, the cured resin constituting the resin layer that fills the inside of the outer coil spring 20 and covers the outer periphery of the outer coil spring 20 has good adhesion to both the outer coil spring 20 and the hydrophilic resin. Specific examples thereof include urethane acrylate resins, polyurethane resins, silicone resins, epoxy resins, acrylic resins, nylon resins, and other photo-curing resins or thermosetting resin cured products. it can.
The film thickness of the resin layer covering the outer periphery and the tip of the outer coil spring 20 is, for example, 1 to 100 μm, and preferably 3 to 10 μm.

As the resin constituting the hydrophilic resin layer laminated on the surface of the resin layer, any resin used in the medical device field can be used.
The thickness of the hydrophilic resin layer is, for example, 1 to 30 μm, preferably 3 to 19 μm.

  In the guide wire of this embodiment, the front end portion and the rear end portion of the inner coil spring 30 are fixed to the distal end side small diameter portion 11 to form a part of the first fixing portion 51 and the second fixing portion 52. The inner coil spring 30 is attached to the core wire 10, and then the distal end portion and the tapered portion 22 of the outer coil spring 20 are fixed to the distal end side small-diameter portion 11 to which the inner coil spring 30 is attached. In addition to forming the portion 51 and the fourth fixing portion 54, the rear end portion of the outer coil spring 20 is fixed to form the third fixing portion 53, so that the outer coil spring 20 covers the inner coil spring 30. It can be manufactured by attaching to the core wire 10.

  According to the guide wire of this embodiment, the front end portion of the outer coil spring 20 and the front end portion of the inner coil spring 30 are fixed to the core wire 10 at the first fixing portion 51, and the rear end portion of the inner coil spring 30 is second fixed. The portion 52 is fixed to the core wire 10, the rear end portion of the outer coil spring 20 is fixed to the core wire 10 at the third fixing portion 53, and the tapered portion 22 of the outer coil spring 20 is fixed to the core wire 10 at the fourth fixing portion 54. As a result, the outer coil spring 20 and the inner coil spring 30 are fixed to the core wire 10 at both ends thereof, and are also fixed to each other at the tip portions thereof, so that the core wire 10 and the inner coil spring 30 are , With the outer coil spring 20 It is possible to improve the physicality (interlocking), and it is possible to prevent the rotational torque from the hand side from decreasing at the taper portion 22, so that it is clear from the results of the examples described later, The torque transmission performance can be sufficiently improved.

In addition, since Au—Sn solder is used as the solder constituting the first fixing portion 51 for fixing the tip portion of the outer coil spring 20 and the tip portion of the inner coil spring 30 to the core wire, Although the length is as short as 0.1 to 0.5 mm (the soldering area is narrow), the fixing strength of the outer coil spring 20 and the inner coil spring 30 to the core wire can be made sufficiently high.
And since the length of the 1st adhering part 51 is as short as 0.1-0.5 mm, shaping length (bending length of a front-end | tip) can be shortened (it shall be 0.7 mm or less), As a result, For example, the frictional resistance can be sufficiently reduced during operation in the microchannel. In addition, treatment in a narrow region that cannot be performed using a conventional guide wire is also possible.

  Further, the winding direction (left direction) of the outer coil spring 20 and the winding direction (right direction) of the inner coil spring 30 are opposite to each other, so that the outer coil spring 20 is located on the proximal end side (hand side). When rotating in the tightening direction (clockwise), the inner coil spring 30 opens, and when rotating the outer coil spring 20 in the opening direction (counterclockwise), the inner coil spring 30 is tightened. There will be no significant difference in torque transmission between when the torque is applied and when the torque is applied in the counterclockwise direction, and any rotational torque in any rotational direction will be transmitted reliably to the distal end. Can do.

  In addition, since the winding direction of the outer coil spring 20 is the left direction and the winding direction of the inner coil spring 30 is the right direction, when the tip of the guide wire of this embodiment is trapped, the timepiece that the operator gives as an initial motion Since the outer coil spring 20 having a relatively large diameter is tightened by the rotational torque around and the inner coil spring 30 having a relatively small diameter is loosened, the outer coil spring of the outer coil spring can be understood from the results of the embodiments described later. Compared with the case where the winding direction is the right direction and the winding direction of the inner coil spring is the left direction, it is possible to obtain further superior torque transmission.

  Furthermore, a fixed portion (second fixed portion 52) of the rear end portion of the inner coil spring 30, a fixed portion (third fixed portion 53) of the rear end portion of the outer coil spring 20, and the outer coil spring 20 with respect to the core wire 10. Since the fixing portion (fourth fixing portion 54) of the taper portion 22 is in a different axial position, the flexibility at the distal end portion can be ensured with a good balance.

Second Embodiment
FIG. 4 shows a cross-sectional configuration of the distal end side portion of the guide wire according to the second embodiment of the present invention. In the same figure, the part shown with the same code | symbol as FIG. 3 is the structure similar to the guide wire which concerns on 1st Embodiment, Therefore Detailed description is abbreviate | omitted.

  Similar to the first embodiment, the guide wire of the present embodiment includes the core wire 10, the outer coil spring 20 whose winding direction is the left direction, and the inner coil spring 30 whose winding direction is the right direction.

  In the guide wire of this embodiment, each of the outer coil spring 20 and the inner coil spring 30 is fixed to the outer periphery of the distal end side small diameter portion 11 of the core wire 10 by solder.

The distal end portion of the outer coil spring 20 and the distal end portion of the inner coil spring 30 are fixed to the outer periphery of the small-diameter portion 11 on the distal end side of the core wire 10 at a first fixing portion 56 made of Au—Sn solder.
That is, the Au—Sn solder constituting the first fixing portion 56 penetrates into the inside of the tip portion of the outer coil spring 20 (tip-side small-diameter portion 21) and inside the tip portion of the inner coil spring 30, and the core wire 10 ( By making contact with the outer periphery of the distal end side small diameter portion 11), the distal end portion of the outer coil spring 20 and the distal end portion of the inner coil spring 30 are fixed to the distal end of the core wire 10 (distal end side small diameter portion 11). .
Thereby, the tip of the inner coil spring 30 is firmly fixed to both the core wire 10 and the outer coil spring 20.

As shown in FIG. 4, a substantially hemispherical tip that is a part of the first fixing portion 56 is formed by Au—Sn solder that has not penetrated into the tip of the outer coil spring 20.
That is, the first fixing portion 56 (rigid portion) is formed by the Au—Sn solder penetrating into the coil spring (the outer coil spring 20 and the inner coil spring 30) and the tip formed by the Au—Sn solder. Is formed.

The middle portion of the distal-side small-diameter portion 21 of the outer coil spring 20 and the rear end portion of the inner coil spring 30 are arranged on the outer periphery of the small-diameter portion 11 on the distal end side of the core wire 10 in the second fixing portion 57 made of Au—Sn solder. It is fixed.
That is, the Au—Sn solder constituting the second fixing portion 57 penetrates into the inside of the intermediate portion and the inside of the rear end portion of the inner coil spring 30 at the distal end side small diameter portion 21 of the outer coil spring 20, and the core wire 10 ( By contacting the outer periphery of the distal end side small diameter portion 11), the intermediate portion of the outer coil spring 20 and the rear end portion of the inner coil spring 30 are fixed to the core wire 10 (distal end side small diameter portion 11).
Thereby, the rear end portion of the inner coil spring 30 is firmly fixed to both the core wire 10 and the outer coil spring 20.

The rear end portion of the outer coil spring 20 is fixed to the outer periphery of the distal end side small diameter portion 11 of the core wire 10 at the third fixing portion 58 made of Ag—Sn solder.
That is, the Ag—Sn solder penetrates into the rear end portion of the outer coil spring 20 (the rear end portion of the rear end side large diameter portion 23), and the outer periphery of the core wire 10 (distal end side small diameter portion 11). By contacting, the rear end portion of the outer coil spring 20 is fixed to the core wire 10 (the distal end side small diameter portion 11).

  In the distal end side small diameter portion 11 of the core wire 10, the outer diameter of the portion to which the rear end side large diameter portion 23 of the outer coil spring 20 is fixed is the portion to which the tip side small diameter portion 21 of the outer coil spring 20 is fixed (distal). Since it is larger than the outer diameter of the edge (relatively large fixing area), it is possible to use an Ag—Sn based solder having a small fixing strength compared to the Au—Sn based solder.

The length of the 1st adhering part 56 shall be 0.1-0.5 mm.
When this length is less than 0.1 mm, it is not possible to sufficiently secure the fixing strength between the outer coil spring and the inner coil spring with respect to the core wire and the fixing strength between the outer coil spring and the inner coil spring.
On the other hand, when the length of the tip rigid portion exceeds 0.5 mm, the shaping length becomes long (cannot be 0.7 mm or less).

  The Au—Sn based solder constituting the first fixing portion 56 and the second fixing portion 57 is a binary or multi-component solder containing Au and Sn as main components, for example, Au 75 to 85 mass%. An alloy composed of an alloy of Sn25 to 15% by mass (Au80Sn20 eutectic solder if a suitable example is shown), an alloy consisting of an alloy of 5 to 15% Au and Sn95 to 85% by mass (based on Au10Sn90 if a suitable example is shown) Crystal solder).

By fixing the constituent material of the core wire 10 (for example, stainless steel) and the constituent material of the outer coil spring 20 and the inner coil spring 30 (for example, the X-ray opaque material described above) using Au—Sn solder, Higher fixing force (tensile strength) can be obtained as compared with the case of fixing with Ag-Sn solder (Ag3.5Sn96.5).
For this reason, even when the length of the tip rigid portion is as short as 0.1 to 0.5 mm, the fixing strength of the outer coil spring 20 to the core wire 10 can be sufficiently increased.
In addition, Au—Sn solder is superior in contrast to Ag—Sn solder.
Furthermore, Au—Sn solder is superior in corrosion resistance to blood and body fluids than Ag—Sn solder.

The guide wire of this embodiment is filled with a hardened resin (not shown) in the inside of the outer coil spring 20 (inner space where the inner coil spring 30 is not mounted and the solder does not permeate). The outer periphery of the outer coil spring 20 and the tip are covered by the resin layer.
And the hydrophilic resin layer which is not illustrated is laminated | stacked and formed on the surface of this resin layer.

  By filling the inside of the outer coil spring 20 with the cured resin, the integrity (interlocking) between the core wire 10 and the outer coil spring 20 is further improved. Thereby, the torque transmission property of a guide wire further improves, and the rotational torque transmitted from the proximal end side large diameter part 13 of the core wire 10 is reliably transmitted to the distal end of a guide wire.

  In addition, since the hydrophilic resin layer is formed on the outer periphery of the outer coil spring 20 via the resin layer (undercoat layer), the hydrophilic resin layer is firmly fixed, and the lubricity by the hydrophilic resin is stabilized. It can be expressed in an experimental manner.

Here, the cured resin constituting the resin layer that fills the inside of the outer coil spring 20 and covers the outer periphery of the outer coil spring 20 has good adhesion to both the outer coil spring 20 and the hydrophilic resin. Specific examples thereof include urethane acrylate resins, polyurethane resins, silicone resins, epoxy resins, acrylic resins, nylon resins, and other photo-curing resins or thermosetting resin cured products. it can.
The film thickness of the resin layer covering the outer periphery and the tip of the outer coil spring 20 is, for example, 1 to 100 μm, and preferably 3 to 10 μm.

As the resin constituting the hydrophilic resin layer laminated on the surface of the resin layer, any resin used in the medical device field can be used.
The thickness of the hydrophilic resin layer is, for example, 1 to 30 μm, preferably 3 to 19 μm.

  In the guide wire of this embodiment, the front end portion and the rear end portion of the inner coil spring 30 are fixed to the distal end side small diameter portion 11 to form part of the first fixing portion 56 and part of the second fixing portion 57. Then, the inner coil spring 30 is attached to the core wire 10, and then the distal end portion and the intermediate portion of the outer coil spring 20 are fixed to the distal end side small diameter portion 11 to which the inner coil spring 30 is attached. The first fixing portion 56 and the second fixing portion 57 are formed, and the rear end portion of the outer coil spring 20 is fixed to form the third fixing portion 58, thereby covering the outer coil spring 20 with the inner coil spring 30. Thus, it can manufacture by mounting | wearing with the core wire 10. FIG.

  Further, the inner coil spring 30 is attached (temporarily attached) to the core wire 10 by fixing the tip of the inner coil spring 30 to the distal end side small diameter portion 11 to form a part of the first fixing portion 56. Then, the distal end portion of the outer coil spring 20 is fixed to the distal end side small diameter portion 11 to which the inner coil spring 30 is attached to form a first fixing portion 56, and the intermediate portion of the outer coil spring 20 is set as the inner coil. By fixing together with the rear end portion of the spring 30 to form the second fixed portion 57, and fixing the rear end portion of the outer coil spring 20 to form the third fixed portion 58, the outer coil spring 20 is connected to the inner coil. You may manufacture by attaching to the core wire 10 so that the spring 30 may be covered.

  According to the guide wire of this embodiment, the distal end portion of the outer coil spring 20 and the distal end portion of the inner coil spring 30 are fixed to the core wire 10 at the first fixing portion 56, and the intermediate portion and inner coil of the outer coil spring 20 are fixed. Since the rear end portion of the spring 30 is fixed to the core wire 10 at the second fixing portion 57, the inner coil spring 30 is fixed to both the core wire 10 and the outer coil spring 20 at both ends thereof. The integrity of the core wire 10, the inner coil spring 30, and the outer coil spring 20 is remarkably improved, and as can be seen from the results of the embodiments described later, the torque transmission can be sufficiently improved. .

In addition, since Au—Sn solder is used as the solder constituting the first fixing portion 56 that fixes the distal end portion of the outer coil spring 20 and the distal end portion of the inner coil spring 30 to the core wire, Although the length is as short as 0.1 to 0.5 mm (the soldering area is narrow), the fixing strength of the outer coil spring 20 and the inner coil spring 30 to the core wire can be made sufficiently high.
And since the length of the 1st adhering part 56 is as short as 0.1-0.5 mm, shaping length (bending length of a front-end | tip) can be shortened (it shall be 0.7 mm or less), As a result, For example, the frictional resistance can be sufficiently reduced during operation in the microchannel. In addition, treatment in a narrow region that cannot be performed using a conventional guide wire is also possible.

  Further, the winding direction (left direction) of the outer coil spring 20 and the winding direction (right direction) of the inner coil spring 30 are opposite to each other, so that the outer coil spring 20 is located on the proximal end side (hand side). When rotating in the tightening direction (clockwise), the inner coil spring 30 opens, and when rotating the outer coil spring 20 in the opening direction (counterclockwise), the inner coil spring 30 is tightened. There will be no significant difference in torque transmission between when the torque is applied and when the torque is applied in the counterclockwise direction, and any rotational torque in any rotational direction will be transmitted reliably to the distal end. Can do.

  Further, when the winding direction of the outer coil spring 20 is the left direction and the winding direction of the inner coil spring 30 is the right direction, when the tip of the guide wire according to the present embodiment is trapped, the watch is given as an initial motion. Since the outer coil spring 20 having a relatively large diameter is tightened by the rotational torque around and the inner coil spring 30 having a relatively small diameter is loosened, the outer coil spring of the outer coil spring can be understood from the results of the embodiments described later. Compared with the case where the winding direction is the right direction and the winding direction of the inner coil spring is the left direction, it is possible to obtain further superior torque transmission.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to these embodiment, A various change is possible.

For example, solder other than Au—Sn solder may be used as the solder constituting the first fixing portion for fixing the tip of the outer coil spring 20 and the tip of the inner coil spring 30 to the core wire 10.
Examples of such solder include Au-based solder other than Au-Sn-based solder, Ag-Sn-based solder, and the like.

Further, the first fixing portion may be constituted by a plurality of types (systems) of solder so as to have a portion made of Au—Sn system solder.
For example, the first fixing portion 511 shown in FIG. 7A is a Au—Sn formed so as to cover the distal end of the core wire 10 as a first fixing portion made of solder containing Au—Sn solder in a part thereof. An inner layer portion 513 made of a solder, and an Ag-Sn solder that fixes the tip of the outer coil spring 20 and the tip of the inner coil spring 30 to the distal end of the core wire 10 so as to cover the inner layer 513 The outer layer part 515 which consists of. The inner layer portion 513 may be entirely covered with the outer layer portion 515 including its proximal end side.

  Further, the first fixing portion 512 shown in FIG. 7B covers the inner layer portion 514 made of Au—Sn solder for fixing the tip portion of the inner coil spring 30 to the distal end of the core wire 10 and the inner layer portion 514. And an outer layer portion 516 made of Ag—Sn solder for fixing the tip of the outer coil spring 20 to the distal end of the core wire 10. The inner layer portion 514 may be entirely covered with the outer layer portion 516 including its proximal end side.

  Each of the first fixing portion 511 and the first fixing portion 512 has such a first fixing portion because the solder constituting the inner layer portion covering the distal end of the core wire 10 is Au—Sn solder. According to the medical guide wire of the present invention, the outer coil spring 20 and the inner coil spring are formed despite the fact that the length of the first fixing portion is as short as 0.1 to 0.5 mm (the fixing area by the solder is narrow). The fixing strength to 30 core wires can be made sufficiently high.

<Example 1>
An inner coil spring 30 in which a wire made of a Pt / W alloy is wound in the right direction is attached to the distal end portion of the small-diameter portion 11 on the distal end side of the core wire 10 made of stainless steel having a coating film made of PTFE formed on the outer peripheral surface. did.
The inner coil spring 30 is attached by fixing its front end portion and rear end portion to the front end portion of the distal end side small-diameter portion 11 with Au80Sn20 eutectic solder. This was performed by forming the fixing portion 52.

Next, an outer coil spring 20 in which a wire rod made of a Pd-Re alloy is wound leftward around the distal end side small diameter portion 11 of the core wire 10 to which the inner coil spring 30 is attached to the tip portion is attached to the inner coil. The spring 30 was mounted so as to cover it.
The outer coil spring 20 is attached by fixing the tip end portion (tip portion of the tip side small diameter portion 21) and the taper portion 22 to the distal end side small diameter portion 11 with Au80Sn20 eutectic solder, respectively. And the rear end portion (rear end portion of the rear end side large diameter portion 23) are fixed to the distal end side small diameter portion 11 with Ag3.5Sn96.5 eutectic solder. This was performed by forming the third fixing portion 53.

Next, the inside of the outer coil spring 20 (inner space where the inner coil spring 30 is not mounted) is filled with a cured resin (urethane acrylate resin), and a resin layer made of a cured resin is formed on the outer periphery of the outer coil spring 20. Furthermore, a hydrophilic resin layer made of polyethylene oxide was laminated on the surface of the resin layer to produce the guide wire of the present invention having the configuration as shown in FIGS.
This guide wire was easy to be attached to the tip portion and excellent in shaping operability.

Here, the dimensions of the guide wire are as follows.
[Core wire 10]
-Outer diameter of the proximal end side large-diameter portion 13: 0.356 mm
-Length of the proximal end side large diameter portion 13: 1500 mm
-Length of taper portion 12: 240 mm
-Outer diameter of the first small diameter portion 111 of the distal end side small diameter portion 11: 0.045 mm
-Length of the first small diameter portion 111 of the distal end side small diameter portion 11: 15 mm
-Outer diameter of the second small diameter portion 113 of the distal end side small diameter portion 11: 0.12 mm
-Length of the second small diameter portion 113 of the distal end side small diameter portion 11: 50 mm
-Length of the taper part 112 of the distal end side small diameter part 11: 25 mm

[Outer coil spring 20]
-Outer diameter of the small-diameter portion 21 at the front end: 0.011 inch (0.279 mm)-Length of the small-diameter portion 21 at the distal end: 38.5 mm
-Length of taper part 22: 1.5 mm
・ Outer diameter of rear end side large diameter portion 23: 0.014 inch (0.356 mm)
-Length of rear end side large diameter portion 23: 125 mm
・ Coil wire diameter: 0.05mm

[Inner coil spring 30]
・ Length: 40mm
・ Outer diameter: 0.14mm
・ Inner diameter: 0.08mm
・ Coil wire diameter: 0.03mm

<Example 2>
A guide wire of the present invention was manufactured in the same manner as in Example 1 except that the winding direction of the inner coil spring was set to the left and the winding direction of the outer coil spring was set to the right.
This guide wire was easy to be attached to the tip portion and excellent in shaping operability.

<Comparative Example 1>
A comparative guide wire was manufactured in the same manner as in Example 1 except that the winding direction of the inner coil spring was set to the left direction.

<Comparative Example 2>
A comparative guide wire was manufactured in the same manner as in Example 1 except that the winding direction of the outer coil spring was set to the right direction.

<Example 3>
An inner coil spring 30 in which a wire made of a Pt / W alloy is wound in the right direction is attached to the distal end portion of the small-diameter portion 11 on the distal end side of the core wire 10 made of stainless steel having a coating film made of PTFE formed on the outer peripheral surface. did.
The inner coil spring 30 is attached by fixing its front end and rear end to the front end of the distal end small-diameter portion 11 with Au80Sn20 eutectic solder. This was performed by forming a part of the fixing portion 57.

Next, an outer coil spring 20 in which a wire rod made of a Pd-Re alloy is wound leftward around the distal end side small diameter portion 11 of the core wire 10 to which the inner coil spring 30 is attached to the tip portion is attached to the inner coil. The spring 30 was mounted so as to cover it.
The outer coil spring 20 is attached to the front end portion (the front end portion of the front end side small diameter portion 21) and the intermediate portion (the intermediate portion in the front end side small diameter portion 21) corresponding to the fixing position of the rear end portion of the inner coil spring 30. The first fixed portion 56 and the second fixed portion 57 are fixed to the distal end side small diameter portion 11 with Au80Sn20 eutectic solder, respectively, and the rear end portion (the rear end of the rear end side large diameter portion 23 is formed). Part) was fixed to the distal end side small diameter part 11 with Ag3.5Sn96.5 eutectic solder to form a third fixing part 53.

Next, the inside of the outer coil spring 20 (inner space where the inner coil spring 30 is not mounted) is filled with a cured resin (urethane acrylate resin), and a resin layer made of a cured resin is formed on the outer periphery of the outer coil spring 20. Further, a hydrophilic resin layer made of polyethylene oxide was laminated on the surface of the resin layer to produce a guide wire of the present invention having a configuration as shown in FIG.
Here, the dimensions of the guide wire are the same as those in the first embodiment.
This guide wire was easy to be attached to the tip portion and excellent in shaping operability.

<Example 4>
A guide wire of the present invention was manufactured in the same manner as in Example 3 except that the winding direction of the inner coil spring was set to the left and the winding direction of the outer coil spring was set to the right.
This guide wire was easy to be attached to the tip portion and excellent in shaping operability.

<Comparative Example 3>
A comparative guide wire was manufactured in the same manner as in Example 3 except that the winding direction of the inner coil spring was set to the left direction.

<Comparative example 4>
A comparative guide wire was manufactured in the same manner as in Example 3 except that the winding direction of the outer coil spring was changed to the right direction.

<Comparative Example 5>
A core wire is attached to the outer periphery of the distal end portion of the core wire along the axial direction. The tip side small diameter portion having an outer diameter of 0.010 inches and a length of 20 mm, a taper portion having a length of 30 mm, an outer diameter of 0. An outer coil spring having a 014 inch length and a rear end large diameter portion of 110 mm in length, which is fixed to the core wire at the front end portion and the rear end portion thereof, and a winding direction of the right side outer coil spring, and the inner side of the outer coil spring Is attached to the outer periphery of the distal end portion of the core wire along the axial direction, and is fixed to the core wire at the front end portion and the rear end portion thereof. The outer diameter is 0.12 mm, the length is 15 mm, and the winding direction is the inner side in the right direction. A commercially available guide wire having a coil spring and having an inner coil spring and an outer coil spring not fixed to each other was prepared.

<Torque transmission evaluation test (trap test)>
Using the apparatus as shown in FIG. 5, the distal end portion of each of the guide wires obtained by Examples 1-2, Comparative Examples 1-2, Examples 3-4, and Comparative Examples 3-5 (about from the distal end). 5 mm) was sandwiched between two silicone sheets (10 mm × 10 mm × 0.5 mm) 61 and a load of 200 g was applied to reproduce the state where the tip of the guide wire was trapped.

  In FIG. 5, G is a guide wire, 63 is a microcatheter, 65 is a torque motor, and 67 and 69 are video cameras.

  FIG. 6 is a photograph (taken by the video camera 67) showing the tip portion of the guide wire G sandwiched between two silicone sheets 61. As shown in FIG. 6, the tip portion of the guide wire Is shaped at its tip (about 0.6 mm from the tip).

Next, in order to reproduce the normal operation by the operator when the tip of the guide wire is trapped, the proximal end (hand side) side of the guide wire is rotated by the torque motor 65 at a rotation speed of 360 ° / second. After three clockwise rotations, three counterclockwise rotations were made.
During this time, by observing the rotation of the torque motor 65 with the video camera 69, the rotation state on the proximal end side of the guide wire G is grasped and the rotation state (the number of rotations, torque on the distal end side of the guide wire G). The presence or absence of a whip phenomenon due to accumulation was observed with a video camera 67.
Here, the whip phenomenon refers to a phenomenon in which torque accumulated from a certain rotation angle on the proximal end side is suddenly transmitted.
The results are shown in Table 1 below.

DESCRIPTION OF SYMBOLS 10 Core wire 11 Distal end side small diameter part 111 1st small diameter part 112 Tapered part 113 2nd small diameter part 12 Tapered part 13 Proximal end side large diameter part 20 Outer coil spring 21 Front end side small diameter part 22 Tapered part 23 Rear end side large Diameter portion 30 Inner coil spring 51, 511, 512 First fixing portion 513, 514 Inner layer portion 515, 516 Outer layer portion 52 Second fixing portion 53 Third fixing portion 54 Fourth fixing portion 56 First fixing portion 57 Second fixing portion 58 Third fixing part

Claims (11)

A core wire having a distal end side small diameter portion and a proximal end side large diameter portion having an outer diameter larger than that of the distal end side small diameter portion;
Attached to the outer periphery of the distal end side small diameter portion of the core wire along the axial direction, the tip side small diameter portion, the rear end side large diameter portion having a coil outer diameter larger than the tip side small diameter portion, and the tip side small diameter An outer coil spring fixed to the core wire at least at the front end portion and the rear end portion, and a taper portion located between the portion and the rear end side large diameter portion,
An inner coil spring which is attached along the axial direction to the outer periphery of the small diameter portion of the distal end side of the core wire inside the outer coil spring, and which is fixed to the core wire at least at the front end portion and the rear end portion. ,
The outer coil spring has a length of 5 to 100 mm at the distal end side small diameter portion and a coil outer diameter of 0.012 inch or less,
The distal end portion of the outer coil spring and the distal end portion of the inner coil spring are fixed to the core wire in a first fixing portion by solder,
The rear end portion of the inner coil spring is fixed to the core wire at a second fixing portion by solder,
The rear end portion of the outer coil spring is fixed to the core wire at a third fixing portion by solder,
The length of the first fixing part is 0.1 to 0.5 mm,
A medical guide wire, wherein a winding direction of the outer coil spring and a winding direction of the inner coil spring are opposite to each other.   2. The medical guide wire according to claim 1, wherein the tapered portion of the outer coil spring is fixed to the core wire at a fourth fixing portion made of solder.   3. The medical use according to claim 1, wherein an intermediate portion of the outer coil spring is fixed to the core wire together with the rear end portion of the inner coil spring in the second fixing portion by solder. Guide wire.   The medical guide wire according to any one of claims 1 to 3, wherein the first fixing portion is made of Au-Sn solder.   The medical guide wire according to any one of claims 1 to 4, wherein a winding direction of the outer coil spring is a left direction.   The medical guide wire according to any one of claims 1 to 5, wherein the second fixing portion is made of Au-Sn solder.   The medical guide wire according to any one of claims 2 to 6, wherein the second fixing portion and the fourth fixing portion are made of Au-Sn solder.   The medical guide wire according to any one of claims 1 to 7, wherein a coil outer diameter of the rear end side large diameter portion of the outer coil spring is 0.014 inches or more. The first fixing part is an inner layer part made of Au-Sn solder covering the distal end of the core wire,
The outer layer part which consists of Ag-Sn type solder which adheres the said distal end of the said core wire, and the said front-end | tip part of the said outer coil spring so that the said inner layer part may be covered is provided. A medical guide wire according to claim 1.   The outer layer portion of the first fixing portion fixes the distal end of the core wire and the tip portion of the inner coil spring so as to cover the inner layer portion. The medical guidewire as described.   The medical guide wire according to claim 9, wherein the inner layer portion of the first fixing portion fixes the distal end of the core wire and the tip portion of the inner coil spring.