JP2002017863A - Guide wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a guide wire capable of being inserted into a target site safely and precisely, keeping low frictional resistance to the inner wall of a blood vessel, etc., and enabling an operator to sense the resistance at the tip part. SOLUTION: The guide wire 1 consists of a core 2 consisting of a main body 3 and a tip part 3 and a coil 6 covering the tip part 4 of the 2. A covering layer 5 more lubricant than the core 2 covers the outer surface of the part 3. The coil 6 has the tip part 61 whose length ranges 0.1 to 10 mm and a lubricant part 62 formed adjacent to the base end of the part 61 and has its surface covered with a first lubricant layer. The part 61 is not more lubricant than the part 62.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a guide wire used for introducing a medical device such as a catheter to a target site in a living body for examination or treatment.

[0002]

2. Description of the Related Art In recent years, for examination and treatment of heart disease and the like,
Introduction of catheters into blood vessels and the like has been performed. Then, in order to introduce such a catheter into a target site in a living body, a guide wire is inserted into the catheter, the distal end of the guide wire is protruded from the distal end of the catheter, and the guide wire is pushed to the target site. Has been performed to follow a guide wire to a target site.

[0003] In recent years, catheters have been introduced into particularly small and very bent blood vessels such as internal blood vessels of the brain, coronary arteries of the heart, blood vessels constituting the kidneys, and very narrow blood vessels. It has become to. Therefore, in order to introduce the catheter into such a blood vessel, the diameter is reduced and the lubrication is high (the friction resistance against the inner wall of the blood vessel is low).
Guidewire is required. Therefore, attempts to improve the lubricity of a guide wire for the purpose of improving the permeability of a stenosis part and the accessibility to a peripheral blood vessel have been actively made. For example, Japanese Patent Application Laid-Open No. Hei 5-168695 discloses a guide wire having improved lubricity by providing a hydrophilic lubricating layer which exhibits high lubricity when wet on the outer surface.

[0004] However, the guide wire disclosed in Japanese Patent Application Laid-Open No. 5-168695 is covered with a hydrophilic lubricating layer up to the forefront, and therefore has high lubricity at the forefront, so that the surgeon can easily remove the guide wire. There is a problem that information cannot be obtained from the tip. In other words, when the distal end of the guide wire hits a bent part of a blood vessel or a stenosis in a blood vessel, the resistance is not transmitted to the surgeon, and the surgeon pushes the guide wire as it is without noticing it. In some cases, the guidewire may move in a wrong direction, or the target site may be overlooked. In addition, there is also a problem that, when it is desired to place the guide wire at the target site, the guide wire slides from the target site without permission.

On the other hand, Japanese Patent Publication No. 5-81272 discloses that
A guidewire is disclosed that is comprised of three segments, a proximal end, a middle end, and a distal end, wherein the distal end has a higher friction surface compared to the middle end.

[0006] This guidewire does not prevent the surgeon from sensing the state-of-the-art resistance and does not have the problem of sliding freely from the indwelling site, but has high friction defined as the distal end. Since the surface is considerably long, such as 10 to 100 mm, the frictional resistance against the inner wall of the blood vessel when running in the blood vessel increases. As a result, when the blood vessel is pushed to the target site, the blood vessel cannot pass through the bent portion of the blood vessel (reduced reach to peripheral blood vessels) and cannot pass through a stenotic part in the blood vessel (decreased permeability of the stenotic part). Such problems come out.

Further, Japanese Patent No. 2657290 discloses that
A guide wire is disclosed in which the tip of the core is covered with a coil, and only the outer surface of the body of the core is coated with a lubricity-imparting agent. Since the length of the coil at the tip end, which is not coated with the imparting agent, is considerably long, that is, 10 to 500 mm, the same problem as that of the guide wire disclosed in Japanese Patent Publication No. 5-81272 occurs.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a safe and secure method capable of maintaining a low frictional resistance against the inner wall of a blood vessel or the like, and further enabling an operator to sense the resistance at the forefront. An object of the present invention is to provide a guide wire that can be accurately inserted into a target site.

[0009]

This and other objects are achieved by the present invention which is defined below as (1) to (4).

(1) a core material comprising a main body and a tip,
A first coating layer having a higher lubricity than the core material, covering at least a part of the body-inserted portion of the main body of the core material,
A coil surrounding the distal end of the core material, wherein the coil has a length of 0.1 to 10;
mm, and a lubricating portion formed adjacent to the base end of the foremost portion and having a surface covered with a lubricating layer. A guide wire having lower lubricity than a lubricated portion.

(2) The guide wire according to (1), wherein the first coating layer has lower lubricity than the lubricating portion.

(3) The lubricating layer is made of a hydrophilic polymer substance exhibiting lubricity when wet, and the length of the leading end is in the range of 1 to 5 mm. The guidewire according to 1) or (2).

(4) The method according to any one of the above (1) to (3), wherein the front end portion is covered with a second coating layer having a lower lubricity than the lubricating layer. Guide wire.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

FIG. 1 is a plan view showing the overall shape of a guide wire according to the present invention, and FIG. 2 is a longitudinal sectional view of the guide wire of FIG. In this specification, the left side of FIGS. 1 and 2 is described as a “base end”, and the right side is described as a “distal end”.

A guide wire 1 according to the present invention shown in FIGS. 1 and 2 comprises a core 2 composed of a main body 3 and a tip 4, and a core 2.
And a coil 6 for wrapping the tip 4.

The total length of the guide wire 1 is 300 to 450
About 0 mm is preferable, and about 1000 to 2000 mm is particularly preferable.

The main body 3 of the core member 2 extends from the base end of the core member 2 and is continuous with a long first straight portion 31 having a substantially constant outer diameter and a distal end side of the first straight portion 31. And a first tapered portion 32 whose outer diameter gradually decreases toward the tip. Further, on the distal end side of the first tapered portion 32, the outer diameter is formed smaller than the first straight portion 31, and the second straight portion 41 is formed.
Is continuous.

The first straight portion 31 of the main body 3
An outer surface extending to the tapered portion 32 is coated with a first coating layer 5 having higher lubricity (lower friction resistance) than the core material 2. Therefore, the guidewire 1 can be easily inserted into and removed from the catheter, and the catheter can be operated on the guidewire 1 without any resistance.

The first coating layer 5 is provided with a lubricating portion 62 described later.
It is preferable that lubricity is lower. By providing such a first coating layer 5, it is possible to prevent the main body portion 3 of the core 2 from slipping by the surgeon when the surgeon operates the guide wire 1.

The constituent material of the first coating layer 5 is not particularly limited as long as it has higher lubricity than the core material 2 and lower lubricity than the lubricating portion 62. For example, a fluorine resin such as polytetrafluoroethylene, Examples include hydrophilic polymer materials and silicone-based materials.

The outer diameter of the guide wire 1 in the first straight portion 31 of the main body 3 is preferably about 0.2 to 1.0 mm, particularly preferably about 0.25 to 0.5 mm.

The distal end portion 4 of the core member 2 has a second straight portion 41 whose outer diameter is substantially uniform, and a second straight portion 41.
And a second tapered portion 42 whose outer diameter is gradually reduced toward the distal end, and which is continuous with the distal end of the second tapered portion 42 and is formed in a thin plate shape. And a flat portion 43 formed.

As described above, the core member 2 is provided between the first straight portion 31 and the second straight portion 41 by the first tapered portion 32.
The second taper portion 42 is provided between the second straight portion 41 and the flat portion 43, and the outer diameter gradually decreases toward the tip. Therefore, since the core material 2 has no portion where the flexibility is rapidly changed, the core material 2 does not bend locally in a blood vessel or the like.

The constituent material of the core material 2 is, for example, Ni
Super-elastic alloys such as -Ti alloy and Ni-Co-Cr alloy; various metal materials such as stainless steel and piano wire.

A coil 6 encloses the tip 4 of the core 2. Then, the base end of the coil 6 is connected to the base end of the second straight portion 41 of the core 2, and the tip of the coil 6 is connected to the front end of the flat portion 43 of the core 2. The fixing portion 7 has a hemispherical shape.

The total length of the coil 6 is preferably about 20 to 1000 mm, particularly preferably about 100 to 450 mm. The outer diameter of the coil 6 is preferably about 0.2 to 1.0 mm, particularly preferably about 0.25 to 0.5 mm. The wire diameter of the coil 6 is 0.05 to 0.10 m
m is preferable, and about 0.07 to 0.08 mm is particularly preferable.

As a constituent material of the coil 6, for example, N
Examples include shape memory alloys such as i-Ti, various metal materials such as stainless steel, gold, platinum, tungsten, and tantalum, and various alloys of these materials.

The material constituting the coil 6 may be different along the axial direction of the guide wire 1. For example, the tip side coil is made of a radiopaque material such as platinum,
The base coil may be formed of a high-strength material such as stainless steel, and the coil 6 may be formed by connecting the base end of the front coil and the front end of the base coil. In this case, in order to secure the connection between the distal coil and the proximal coil, it is preferable to fix the inner surface of the coil 6 and the outer surface of the core material 2 near the connection using a braze or the like. .

The coil 6 has a front end portion 61 and a front end portion 6.
1 has a lubricating portion 62 formed adjacent to the base end, the surface of which is covered with a lubricating layer (not shown). By providing the coil 6 with the lubricating portion 62, the frictional resistance against the inner wall of a blood vessel or the like can be reduced, and the accessibility to the peripheral blood vessel and the passage of the stenotic part are improved.

As a material constituting the lubricating layer, for example,
Cellulose-based polymer, polyethylene oxide-based polymer, maleic anhydride-based polymer (eg, maleic anhydride copolymer such as methyl vinyl ether-maleic anhydride copolymer), acrylamide-based polymer (eg, , Polyacrylamide, polyglycidyl methacrylate-dimethylacrylamide (PGMA-DMA
A) block copolymer), hydrophilic polymer materials such as water-soluble nylon, fluorine-based resins such as polytetrafluoroethylene, and silicone-based materials.

The foremost portion 61 has lower lubricity than the lubricating portion 62. By providing such a foremost part 61,
Since the surgeon can sense the resistance of the distal end portion 61, when the distal end portion 61 abuts against a bent portion of a blood vessel, a stenosis portion in a blood vessel, or the like, the operator does not notice the guide wire 1 as it is. There is no such thing as pushing forward. Further, when the guide wire 1 is placed in a blood vessel, the guide wire 1 does not slide and move from the placement site.

The length of the foremost part 61 is 0.1 to 10 mm
The range is not particularly limited as long as it is within the range, and may be appropriately selected depending on the material constituting the lubricating layer of the lubricating portion 62.

For example, when the lubricating layer of the lubricating part 62 is made of a hydrophilic polymer material, the length of the foremost part 61 is
0.5 to 10 mm is preferable, 1 to 5 mm is more preferable, and 1 to 3 mm is most preferable. In addition, for example, when the lubricating layer of the lubricating part 62 is made of a fluorine-based resin such as polytetrafluoroethylene or a silicone-based material, the length of the foremost part 61 is preferably 0.1 to 5 mm, 0.3 to 3 mm is more preferable, and 0.5 to 1.5 m
m is most preferred.

The length of the foremost portion 61 may be selected according to the first effect (the effect that is most important). For example, when the first effect is that the guide wire 1 does not slide freely from an indwelling site such as a blood vessel, the length of the distal end portion 61 is determined regardless of the material of the lubricating layer of the lubricating portion 62. 3 to 10 mm is preferable, and 5 to 10 mm
Is more preferable, and 8 to 10 mm is most preferable.

It should be noted that the length of such a front end portion 61 is 1
If the thickness is 0 mm or more, frictional resistance against the inner wall of a blood vessel or the like becomes high, so that problems such as a decrease in reach to peripheral blood vessels and a decrease in permeability of a stenotic part appear.

Further, the leading end portion 61 may be covered with a second coating layer (not shown) having a lower lubricity than the lubricating layer.
By providing such a second coating layer, the accessibility to the bent portion of the blood vessel and the passage of a stenotic part in the blood vessel are improved. In this case, the second coating layer is formed by
Lubricating part 62 so that the resistance of the foremost part 61 can be sensed.
It does not have lubricity like the lubricating layer described above.

The constituent material of the second coating layer is not particularly limited as long as it has lower lubricity than the material forming the lubricating layer. For example, a fluororesin such as polytetrafluoroethylene or an antithrombotic material such as gelatin can be used. And silicone-based materials.

[0039]

The present invention will be described more specifically with reference to the following examples.

Example 1 Total length 1800 mm, outer diameter 0.
As shown in FIG. 2, the outer surface of the guide wire (made by LakeRegion) 36 mm in which the distal end portion 4 of the core material 2 is wrapped with the coil 6, as shown in FIG.
N, N-dimethylacrylamide-glycidyl methacrylate-diblock copolymer (manufactured by Terumo Corporation)
After immersion in a wt% N, N-dimethylformamide (DMF) solution, it was left at room temperature for 2 hours. And 2 from the cutting edge
After wiping with a cotton swab sufficiently immersed in DMF to the position of mm to remove the copolymer, reaction drying was performed at 180 ° C. for 1 hour. Thus, the guide wire 1 having the foremost portion 61 (length: 2 mm) whose surface was not coated at all and the lubricating portion 62 whose surface was coated with the above copolymer was produced.

With respect to the guide wire 1, the friction resistance was measured by a test shown in FIG. 3 as an index of lubricity. Hereinafter, the test method will be specifically described.

A silicone valve element 100 having a cross-shaped cut at the center is placed on a plate 102 of a cylindrical fixture 101, and a lid 103 is put on the valve element 1 from above.
00 was fixed. Then, the inside of the fixture 101 is filled with water 10.
4 and the guide wire 1 was inserted into the fixture 101 through the hole of the lid 103, the cut of the valve element 100, and the hole of the fixture 101. 20m from the tip
After confirming that the guide wire 1 has been inserted below the valve body 100 by at least m, the guide wire 1 is moved at a speed of 10 mm / using an autograph (AGS-100A, manufactured by Shimadzu Corporation).
Then, the frictional resistance between the guide wire 1 and the valve body 100 was measured. Table 1 shows the results.

In order to confirm what kind of movement the tip wire 61 of the guide wire makes when it hits an inner wall of a blood vessel or the like, an imaginary test as shown in FIG. 4 was performed. Hereinafter, the test method will be specifically described.

In water, the leading end of the guidewire 1 is the upper surface 20 of a 5 mm thick silicone rubber 200.
The guide wire 1 was fixed with the fixture 202 so as to be in contact with the guide wire 1. At this time, the angle 203 between the upper surface 201 of the silicone rubber 200 and the axis of the guide wire 1 was set to 80 °, and the upper surface 201 of the silicone rubber 200 and the fixture 2 were fixed.
The distance 204 with respect to 02 was 30 mm. The silicone rubber 201 was used as a substitute for a blood vessel wall. And
Autograph (AGS-100A, Shimadzu Corporation)
Guide wire 1 at a speed of 500 mm / mi.
At n, the behavior was observed by pushing 5 mm into the silicone rubber 201 side. Table 2 shows the results.

(Example 2) The tip portion 61 (length 2 mm) of the guide wire 1 manufactured in Example 1 was replaced with a reactive silicone oil (NCT911, manufactured by Terumo Corporation) at 10 watts.
After being immersed in a t% hexane solution, it was left at room temperature for 18 hours to produce a guide wire 1 in which the most distal portion 61 was covered with silicone oil. Then, as in Example 1, the tests shown in FIGS. 3 and 4 were performed. The results are shown in Tables 1 and 2.

(Comparative Example) With respect to the same guide wire as in Example 1, without peeling the N, N-dimethylacrylamide-glycidyl methacrylate-diblock copolymer up to a position of 2 mm from the tip, at 180 ° C. Perform reaction drying for hours. A guide wire coated with the above-described copolymer up to the leading end of the coil 6 was produced. Then, as in Example 1, the tests shown in FIGS. 3 and 4 were performed. The results are shown in Tables 1 and 2.

[0047]

[Table 1]

[0048]

[Table 2]

[0049]

As described above, the guide wire of the present invention covers the core comprising the main body and the distal end, and covers at least a part of the insertion portion of the core into the body of the main body. In a guide wire having a first coating layer having higher lubricity than a core material and a coil encasing the distal end of the core material, the coil has a length in a range of 0.1 to 10 mm. And a lubricating part formed adjacent to the base end of the foremost part and having a surface covered with a lubricating layer, wherein the foremost part has more lubricity than the lubricating part. Because of its low feature, the surgeon can sense the resistance at the forefront, and can safely and accurately insert it into the target site. Further, since the frictional resistance against the inner wall of the blood vessel or the like can be kept low, the reachability to the peripheral blood vessel and the passage property of the stenosis part are not impaired. Further, since the guide wire can be easily inserted into and removed from the catheter, the operability is excellent.

When the first coating layer is characterized in that the lubricating portion is less lubricious than the lubricating portion, the operability is further improved because the surgeon does not slip by hand. .

Further, in the case where the lubricating layer is made of a hydrophilic polymer substance exhibiting lubricity when wet, and the length of the leading end is in the range of 1 to 5 mm, Since the frictional resistance of the lubricating portion to the inner wall of the blood vessel or the like can be reduced, the accessibility to the peripheral blood vessel and the passage property of the stenotic part are improved.

Further, in the case where the foremost part is characterized in that the surface is covered with a second coating layer having a lower lubricity than the lubricating layer, the accessibility to peripheral blood vessels and the stenosis part can be further improved. Passability is improved.

[Brief description of the drawings]

FIG. 1 is a plan view showing the overall shape of a guide wire according to the present invention.

FIG. 2 is a longitudinal sectional view of the guide wire of FIG. 1;

FIG. 3 is a schematic diagram showing a method for testing lubricity in the present invention.

FIG. 4 is a schematic view showing a test method assuming that the guide wire according to the present invention abuts on a blood vessel wall.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Guide wire 2 Core material 3 Main part 31 1st straight part 32 1st taper part 4 Tip part 41 2nd straight part 42 2nd taper part 43 Flat part 5 1st coating layer 6 Coil 61 Top end part 62 Lubrication part 7 Fixing part 100 Valve element 101 Fixture 102 Plate 103 Lid 104 Water 200 Silicone rubber 201 Upper surface 202 Fixture 203 Angle 204 Distance

Claims (4)

[Claims] 1. A core material comprising a main body and a tip portion, and a first coating layer, which covers at least a part of a body insertion portion of the core in the body and has higher lubricity than the core material, A guide wire having a coil encasing the distal end portion of the core material, wherein the coil has a length in a range of 0.1 to 10 mm; A lubricating part, the surface of which is covered with a lubricating layer, wherein the leading end has lower lubricity than the lubricating part. 2. The guide wire according to claim 1, wherein the first coating layer has lower lubricity than the lubricating portion. 3. The lubricating layer according to claim 1, wherein the lubricating layer is made of a hydrophilic polymer material exhibiting lubricity when wet, and the length of the tip is in the range of 1 to 5 mm. 3. The guidewire according to any one of items 1 to 2. 4. The guidewire according to claim 1, wherein a surface of the leading end is covered with a second coating layer having a lower lubricity than the lubricating layer.