JP3380691B2 - Guide wire - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a guide wire, and more particularly to a guide wire having a function of guiding a catheter or the like to a target site in a living body.

[0002]

2. Description of the Related Art Guidewires are used for treatment / examination for the purpose of minimally invasive the surgical site or the human body, for example, PTCA (Percutaneous Transluminal Coronary).
Angioplasty: Percutaneous coronary angioplasty) etc. for guiding catheters. Of these, the guide wire used in the PTCA operation is inserted into the catheter prior to the insertion of the catheter into the blood vessel, and the guide wire distal end portion together with the catheter is positioned near the target vascular stenosis so that the distal end of the guide wire precedes. Used to guide up to. The distal end of this catheter has various shapes according to the purpose of use and the site of use, and is flexible enough to follow the complicated bends in the blood vessel and the body.

Therefore, a guide wire used for inserting such a catheter into a blood vessel and a body has appropriate flexibility, pushability for transmitting an operation at hand at the proximal end to the distal end, and torque transmission. Properties (collectively referred to as “operability”), kink resistance (bending resistance), and the like are required. Among these characteristics, a structure with a flexible metal coil around the thin tip core material of the guide wire, and a super-material such as nitinol as the core material of the guide wire are provided as a structure for obtaining appropriate flexibility. Some use elastic wires.

In the conventional guide wire, the core material is substantially 1
The guide wire is made of various kinds of materials, and a relatively high-rigidity material is used in order to enhance the operability of the guide wire, and as a result, the flexibility of the guide wire distal end is lost. Further, if a material having relatively low rigidity is used to obtain flexibility of the distal end portion of the guide wire, the operability at the proximal end portion of the guide wire is lost. Thus, it has been difficult to satisfy the required flexibility and operability with one kind of core material.

In order to improve such a defect, for example, a Ni-Ti alloy wire is used as a core material, and the tip end portion and the base end portion are heat treated under different conditions to enhance the flexibility of the tip end portion.
A guide wire having improved rigidity at the proximal end has been proposed.
However, there is a limit to the control of flexibility by such heat treatment, and even if sufficient flexibility is obtained at the tip end portion, sufficient rigidity may not always be obtained at the base end portion.

Further, in order to satisfy the flexibility at the tip end and the high rigidity at the base end, a guide wire in which a Ni--Ti alloy wire and a stainless wire are connected using a tubular connecting member of Ni--Ti alloy. Is disclosed in Japanese Patent Application Laid-Open No. 4-9162. The tubular connecting member of the Ni—Ti alloy wire used here has uniform rigidity as a whole, so that the N-Ti alloy wire having different rigidity is
A relatively large difference in rigidity occurs at the connection point between the i-Ti alloy wire and the stainless wire.

Stress concentration occurs at a portion where such a difference in rigidity occurs, which causes a kink or deteriorates operability.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a guide wire excellent in operability and kink resistance by providing continuity in the change in rigidity in the longitudinal direction of the wire.

[0009]

The above objects are achieved by the present invention described in (1) to (6) below.

(1) A flexible first wire arranged on the distal end side, and a second wire arranged on the proximal side from the first wire and having a rigidity higher than that of the first wire. A tubular connecting member for connecting the first wire and the second wire, wherein the connecting member is the first
A guide wire having a function of reducing the rigidity of the connecting member is formed at a position closer to the tip end side than the boundary portion between the wire and the second wire.

(2) A flexible first wire arranged on the distal end side, and a second wire arranged on the base end side of the first wire and having a rigidity higher than that of the first wire. A tubular connecting member for connecting the first wire and the second wire, wherein the connecting member is the first
A slit having a function of reducing the rigidity of the connecting member is formed at a position closer to the tip end side than the boundary portion between the second wire and the second wire, and the rigidity near the base end part of the first wire is the wire longitudinal direction. A guide wire characterized in that it is configured to vary continuously along.

(3) The guide wire according to the above (1) or (2), wherein the slits are formed so as to become denser toward the tip of the connecting member.

(4) Any of the above (1) to (3), wherein the second wire is made of a metallic material, and the connecting member is made of the same or the same kind of material as the second wire. A guide wire as described in Crab.

(5) The guide wire according to the above (4), wherein the first wire is made of a superelastic metal and the second wire is made of stainless steel.

(6) The connection end faces of the first wire and the second wire are inclined at a predetermined angle with respect to a plane whose axes are normal to both wires. The guide wire according to any one of 1) to (5).

[0016]

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The guide wire of the present invention will now be described in detail with reference to the preferred embodiments shown in the accompanying drawings.

FIG. 1 is an overall side view of the guide wire of the present invention. The guide wire 1 of the present invention is a guide wire 1.
Has a wire main body (core wire) mainly constituting the. This wire body has a first wire A arranged on the tip side thereof.
And a second wire B arranged on the base end side of the wire body, and the base end portion of the first wire A and the second wire B.
Is connected to the distal end portion thereof by being covered with a tubular connecting member 12.

The first wire A is a flexible wire material, and its constituent material is not particularly limited. For example, various plastics and various metals can be used.
It is preferably composed of a superelastic alloy. As a result, the tip of the wire body having excellent operability and kink resistance can be obtained without increasing the diameter of the first wire A.

Here, the superelastic alloy is generally called a shape memory alloy, and is an alloy exhibiting superelasticity at the operating temperature.
Superelasticity refers to the property of recovering almost the original shape even when deformed (bent, pulled, compressed) to the region where ordinary metal is plastically deformed at a use temperature, that is, at least a living body temperature (around 37 ° C). .

The preferred composition of the superelastic alloy is 49
.About.58 atomic% Ni Ti--Ni alloy, 38.5-41.
Cu-Zn alloy of 5 wt% Zn, 1-10 wt% X of C
u-Zn-X alloy (X is Be, Si, Sn, Al, G
At least one of a), and a superelastic body such as a Ni-Al alloy having 36 to 38 atomic% Al. Among these, the Ti-Ni alloy is particularly preferable.

The second wire B is a flexible wire material, and its constituent material is not particularly limited, and various plastics and various metals can be used. However, the rigidity of the first wire A is not limited. It is composed of a material having greater rigidity, especially a metallic material. As a result, a wire body having excellent operability and kink resistance can be obtained without increasing the diameter of the second wire B.

Further, in order to improve operability and kink resistance, the outer diameter of the second wire B can be made larger than the outer diameter of the first wire A (see the second wire B in FIG. 1). ). In this case, the second portion of the portion covered by the connecting member 12
The outer diameter of the wire B is to improve connection ease.
It is preferable to make it equal to the outer diameter of the portion of the first wire A covered by the connecting member 12.

Preferred examples of the metal material used for the second wire B include metal materials such as stainless steel and piano wire. Among these, stainless steel having excellent rigidity is particularly preferable.

The connecting member 12 is flexible and has a first structure.
Has an opening 122 through which the wire A is inserted and an opening 123 through which the second wire B is inserted, and the opening 122 and the opening 123 are electrically connected to each other and have a tubular shape.

By thus forming the connecting member 12 into a tubular shape, the connecting process between the first wire A and the second wire B becomes easy, and the rigidity in the circumferential direction becomes uniform.

The constituent material of the connecting member 12 is not particularly limited, and various plastics and various metals can be used similarly to the first wire A and the second wire B. In particular, the connecting member 12 is preferably made of a material whose rigidity is higher than the rigidity of the first wire A, and more preferably made of the same or similar material as the second wire B. preferable.

Here, when the rigidity of the connecting member 12 is equal to or less than the rigidity of the first wire A, the rigidity of the portion of the connecting member 12 is the rigidity of the first wire A encapsulated in the connecting member 12. And the rigidity of the second wire B. In such cases,
A large difference in rigidity between the first wire A and the second wire B occurs at the boundary portion 124 between the first wire A and the second wire B encapsulated in the connecting member 12.

On the other hand, when the rigidity of the connecting member 12 is larger than that of the second wire B, the rigidity of the portion of the connecting member 12 depends on the rigidity of the connecting member 12 itself. In such a case, there is no difference in rigidity at the connecting member 12,
The boundary between the opening 122 and the first wire A, and the opening 12
A large difference in rigidity occurs at the boundary between the third wire B and the third wire B.
Since stress concentration occurs at a portion where such a large difference in rigidity occurs, mechanical energy is not smoothly transferred, and operability and kink resistance are impaired.

The preferred composition of the superelastic alloy used for the connecting member 12 is the Ti--Ni alloy and the C.
u-Zn alloy, the Cu-Zn-X alloy (X is Be,
At least one kind of Si, Sn, Al, and Ga), the Ni-Al alloy, the superelastic body such as the stainless steel. Particularly, as the connecting member 12, the connecting member 12
In order to continuously form a value equal to or less than the rigidity value of the second wire B from the rigidity value of the first wire A, it is preferable to have a rigidity equivalent to that of the second wire B. This is because the rigidity value can be easily reduced by processing the connecting member 12.

The connecting member 12 is made of the same or similar metal as the first wire A or the second wire B in order to easily connect the first wire A and the second wire B. Is preferred. In particular, it is preferable to use the same or similar metal as the second wire B.

Further, the thickness between the inner surface and the outer surface of the tubular connecting member 12 is 0.02 to 0.06 from the viewpoint that necessary and sufficient strength can be secured and operability can be improved.
mm is preferable, and 0.03 to 0.05 mm is more preferable.

In the present invention, the rigidity of the connecting member 12 is
In order to gradually and continuously change (in particular increase) the rigidity of the wire A to the rigidity of the second wire B, the connection member 12 is subjected to predetermined processing. Specifically, as shown in (1) and (2) of FIG. 2, it is preferable to form a spiral slit in the encapsulating portion 121 of the connecting member 12 encapsulating the first wire A. Such a slit is
It has a function of reducing the rigidity of the connecting member 12.

Further, as shown in (3) to (4) of FIG. 2, the enclosing portion 1 of the connecting member 12 encapsulating the first wire A.
For example, a horizontal line slit (see (3) in FIG. 2) and a vertical line slit (see (4) in FIG. 2) can be formed in the groove 21.

Further, the slits are formed on the first wire A and the second wire.
It is preferable not to straddle the boundary portion 124 with the wire B. Forming a slit in the boundary portion 124 includes:
This is because the rigidity of the boundary portion 124 is reduced and a kink may occur.

Such a slit changes the rigidity of that portion in accordance with the interval and pitch thereof. For more information,
As described above, a material having the same rigidity as that of the second wire B is used as the connecting member 12, and as shown in FIGS. 1 to 3, the first wire A side (tip side) of the connecting member 12 is The rigidity value of the connecting member 12 encapsulating the first wire A is set to the first value by forming the slits such that the intervals or pitches are made dense and the intervals or pitches become coarser as they approach the boundary portion 124. Second from the stiffness value of wire A
It is possible to continuously change (especially increase) the rigidity value of the wire B.

Needless to say, the slit formation pattern is not limited to that shown in the drawing.

Further, the tip portion 111 of the first wire A is
Is not particularly limited, but it is more preferable that the tip portion 111 is filled with an X-ray contrast material 112, and that a smooth coating of a polymeric material such as synthetic resin is applied so that the tip has a roundness. . X-ray contrast material 1
By using 12, the distal end position of the guide wire 1 can be confirmed on the monitor under fluoroscopy. In addition, the coating portion 113 made of a polymer material
The guide wire 1 can prevent the defect of the inner wall of the blood vessel due to the contact with the blood vessel wall.

The outer diameter of the first wire A is preferably gradually reduced toward the tip. The X-ray contrast material 112 is used by gradually decreasing the amount.
Even if it is encapsulated or coated with synthetic resin 113, the tip portion 111 can maintain a constant outer diameter. The operation of inserting the guide wire 1 into the blood vessel from the distal end side and reaching the target site can be flexibly dealt with in a complicated blood vessel shape such as curve and branch of the blood vessel and can be safely performed.

As the X-ray contrast material 112, for example, a wire of an X-ray opaque material (for example, a metal wire of gold, platinum, etc.) can be wound into a coil and enclosed.

As the polymer material forming the coating portion 113, polyethylene, polyvinyl chloride, polyester, polypropylene, polyamide, polyurethane, polystyrene, polycarbonate, fluorine resin (PTFE, ETFE, etc.), silicone rubber, and various other materials can be used. Elastomers or composite materials thereof are preferably used. In particular, a wire having flexibility equal to or lower than that of the first wire A is preferable.

Further, it is preferable that a layer (not shown) made of a hydrophilic polymer substance having lubricity in a wet state is formed on the outer peripheral surface of the coating portion 113. Thereby, when the guide wire 1 is inserted, friction is reduced, the insertion can be smoothly performed, and operability and safety are improved.

As the hydrophilic polymer substance, a natural polymer substance type (eg, starch type, cellulose type, tannin / nignin type, polysaccharide type, protein) and synthetic polymer type substance (PVA) are used. System, polyethylene oxide system, acrylic acid system, maleic anhydride system, phthalic acid system, water-soluble polyester, ketone aldehyde resin, (meth) acrylamide system, vinyl heterocyclic system, polyamine system, polyelectrolyte, water-soluble nylon system, Glycidyl acrylate type).

Among these, in particular, a cellulosic polymer material (for example, hydroxypropyl cellulose),
Polyethylene oxide-based polymer (polyethylene glycol), maleic anhydride-based polymer (eg, maleic anhydride copolymer such as methyl vinyl ether maleic anhydride copolymer), acrylamide-based polymer (eg, polydimethyl) Acrylamide), water-soluble nylon (for example, AQ-nylon P-70 manufactured by Toray Industries, Inc.)
Alternatively, derivatives thereof are preferable because a low coefficient of friction can be stably obtained in blood. The details of these are described in Japanese Patent Application No. 7-270519.

Further, it is preferable that the second wire B is subjected to a treatment for suppressing the friction generated by the contact with the inner wall of the catheter used simultaneously with the guide wire 1. Specifically, at the hand portion (base portion) 131 where the second wire B contacts the inner wall of the catheter, a substance having a low friction coefficient with respect to the material of the inner wall of the catheter (for example, a fluororesin such as polytetrafluoroethylene or silicone Etc.) may be coated. By suppressing the friction, the operability of the second wire B in the catheter can be maintained without being impaired.

The first wire A, the connecting member 12, the second
Each diameter of the wire B is not particularly limited, but when used for insertion of a PTCA catheter, each diameter (average) is 0.25 to 0.65 mm (0.010 to 0.02 mm).
5 inches) is preferable, and 0.36 to 0.4
More preferably, it is about 5 mm (0.014 to 0.018 inch).

The connection of the first wire A and the second wire B in the connection member 12 is not particularly limited, but the connection member 12 and the first wire A and the second wire B are welded to each other. It is preferable to fix it. For example, as shown in FIG. 2, an end surface of the first wire A cut at a predetermined angle (θ) with respect to a surface having the axes of the wires A and B as a normal line and the end surface of the first wire A are matched with each other. Then, the end surface of the similarly cut second wire B is brought into contact with the inside of the connection member 12 to perform connection. Where the angle θ
Should be θ ≦ 90 degrees, preferably 0 <θ ≦ 45 degrees, and more preferably 0.5 ≦ θ ≦ 20 degrees. The reason is that the first wire A and the second wire B
This is because it is possible to reduce a sudden change in rigidity in the vicinity of the contact end surface with and to obtain excellent kink resistance.

The connecting method is not particularly limited, and may be any ordinary method such as spot welding using a laser. The welded portion may be, for example, a portion including the front end side and the base end side of the boundary portion 124, and is not particularly limited. The entire connecting member 12 may be welded, or only the periphery of the boundary portion 124 (excluding the portion where the slit is formed) may be welded. Also, the connecting member 1
The end faces of both ends of 2 may be fixed by adhesion. As the thickness of the connecting member 12 becomes thinner to some extent, the connecting material is more easily melted and the weldability is improved. Therefore, the thickness of the connecting member 12 is preferably in the range as described above.

When the connecting member 12 is made of stainless steel, which is a highly rigid material, the thickness thereof can be reduced, and the connectability, particularly the weldability with the first wire A is improved. Also, a second wire B made of stainless steel
On the other hand, when the connecting member 12 is made of the same kind of stainless steel, they obtain excellent weldability due to the same composition.

The connection can also be performed by caulking. The caulking process can be easily performed by strongly pushing the first wire A and the second wire B into the connecting member 12 from opposite sides and pressing the boundary portions 124 from the outside. The caulking process can be used in combination with the welding. In order to enhance the connectivity by such a caulking process, it is preferable that the connection end faces of both wires A and B are inclined as described above. Due to the inclination of the end faces, when the wires A and B are pressed so that they come into contact with each other, a deviation occurs in opposite directions with respect to the axes of the wires A and B at the boundary portion 124. Is formed and the connection member 1
It can be caulked by the expansion force from the inside of 2. Inclining the connection end faces of the wires A and B in this manner also has the effect of alleviating the change in rigidity at the boundary portion 124.

Further, FIG. 3 shows a connection procedure of another connection method. In the same figure, the procedure of butt seam welding, which is an example of butt resistance welding, is shown.

In the procedure, the first wire A and the second wire B set in the butt welder (not shown) are shown. The connecting member 12 is fitted in advance on the tip side of the first wire A.

In the procedure, the first wire A and the second wire B are separated from each other by the butt welding machine while applying a predetermined voltage to the end surface of the first wire A on the base end side and the second wire B. Is brought into pressure contact with the end surface on the tip side of the. By this pressure contact, a molten layer is formed at the contact portion, and the first wire A
And the second wire B are firmly connected.

In the procedure, the protruding portion of the connection portion deformed by pressure contact is removed so that the connection member 12 can cover the connection portion.

Then, in a procedure, the connecting portion is covered with the connecting member 12. In the procedure, the connection member 12 is fixed to the first wire A and the second wire B at the ends thereof by the predetermined adhesive 20.

As described above, in addition to the spot welding,
First by butt seam welding (butt resistance welding)
The wire A and the second wire B can be connected.

Further, the connection methods are not limited to the above, and other methods such as brazing (soldering) or adhesive bonding may be used.

The operability and kink resistance of the guide wire 1 as described above are clarified by the bending rigidity measurement described below.

FIG. 4 shows the bending stiffness measurement points near the connecting member 12 of the guide wire 1 of the present invention and the bending stiffness measurement points near the connecting member 12 of the guide wire 10 of the comparative example of the present invention.

Here, the first used for the guide wire 1
The wire A is made of the above Ti-Ni alloy,
2 and the second wire B are made of the stainless steel.
The guide wire 10 as a comparative example is the same as the guide wire 1 except that no slit is formed in the connecting member 12.

Bending rigidity measurement points are indicated by arrows 1 to 3 in FIG.
It is 14. Arrows 1 to 13 are set at intervals of 5 mm, and only the arrow 14 indicates the bending stiffness measurement point of the second wire B.

The bending stiffness is measured by the guide wires 1, 10
In, the arrow indication part (arrows 1 to 14) to be the measurement point
A fulcrum for supporting the guide wires 1 and 10 was provided at a position of 1/2 inch in the front and rear, and the load required to push the arrow pointing portion by 2 mm was measured.

The arrows 1 and 2 of the guide wire 1 indicate the bending rigidity measurement points of the first wire A portion, and the arrows 3 to 10 indicate the bending rigidity in which the slit of the connecting member 12 encapsulating the first wire A is formed. A measurement point is shown, an arrow 11 shows a bending rigidity measurement point where the slit of the connection member 12 encapsulating the first wire A is not formed, and an arrow 12 shows a boundary portion 124,
The arrow 13 indicates the bending stiffness measurement point for enclosing the second wire B, and the arrow 14 indicates the bending stiffness measurement point for the second wire B portion (thick diameter portion).

The arrows 1 and 2 of the guide wire 10 indicate the bending stiffness measurement points of the first wire A portion, and the arrows 3 to
Reference numeral 11 indicates a bending rigidity measurement point of the slit-less connection member 12 enclosing the first wire A, and an arrow 12 indicates a boundary portion 1
24, an arrow 13 indicates a bending stiffness measurement point that wraps the second wire B, and an arrow 14 indicates a bending stiffness measurement point of the second wire B portion (thick diameter portion).

Table 1 shows bending stiffness measurement values measured by the arrow pointing portions (arrows 1 to 14) of the guide wires 1 and 10.

[0066]

[Table 1]

Further, in FIG. 5, the bending stiffness measurement values shown in Table 1 are graphed. The vertical axis of the graph is the bending rigidity value (g), and the horizontal axis is the bending rigidity measurement point indicated by the arrow 1 above.
~ 14 are shown.

From the measured flexural rigidity values, the following can be recognized. (1) By forming the measurement slits in the guide wire 1 so that the pitch of the measurement slits changes from dense (arrow 3) to coarse (arrow 10), the measured values at arrows 3 to 10 are the first wire A. From the bending rigidity value of the first wire A to the bending rigidity value of the connecting member 12 in the state where there is no slit for enclosing the first wire A, and further, through the portion of the arrow 13 and the arrow 14 The flexural rigidity values also change continuously up to the part. Thus, it can be seen that when the guide wire 1 is bent, a smooth curved state without a kink can be obtained.

(2) Measurement with guide wire 10 There is a large difference in bending stiffness between arrow 2 and arrow 3,
From this, it is understood that when the guide wire 10 is bent, a sharp bend is likely to occur. The above tendency also applies to the torsional rigidity of the wire.

[0070]

As described above, the guide wire 1 of the present invention is
The rigidity of the connecting member 12 can be continuously changed from the rigidity of the first wire A to the rigidity of the second wire B. That is, in the connecting member 12 of the guide wire 1, it is possible to prevent the occurrence of a large rigidity difference and disperse the stress concentration by generating a large number of small rigidity differences. This means that the operability and kink resistance of the guide wire 1 are improved as compared with the guide wire 10.

FIGS. 6 and 7 are views showing the usage state when the guide wire 1 of the present invention is used for PTCA surgery.

6 and 7, reference numeral 4 is the aortic arch, reference numeral 5 is the right coronary artery of the heart, reference numeral 6 is the right coronary artery opening,
Reference numeral 7 is a blood vessel stenosis. Further, reference numeral 3 is a guiding catheter for surely guiding the guide wire 1 from the femoral artery to the right coronary artery, and reference numeral 21 is a balloon for dilating a stenosis at a distal end portion 111 of the guide wire 1 having an expandable / contractible balloon. It is a catheter.

As shown in FIG. 6, the tip of the guide wire 1 is projected from the tip of the guiding catheter 3 and inserted into the right coronary artery 5 through the right coronary artery opening 6. Further, the guide wire 1 is advanced, inserted into the right coronary artery from the tip, and stopped at a position where the tip exceeds the vascular stenosis portion 7. Thereby, the passage of the balloon catheter 2 is secured.

Next, as shown in FIG. 7, the guide wire 1
The distal end of the balloon catheter 2 inserted from the proximal end side of the catheter is projected from the distal end of the guiding catheter 3, further advanced along the guide wire 1, and inserted into the right coronary artery 5 through the right coronary artery opening 6 to form a balloon. Stops when it reaches the position of the blood vessel stenosis 7.

Next, a balloon expanding fluid is injected from the proximal end side of the balloon catheter 2 to expand the balloon 21 and expand the blood vessel stenosis 7. By doing so, the deposits such as cholesterol attached and deposited on the blood vessels of the blood vessel stenosis portion 7 are physically spread, and the blood flow obstruction can be eliminated.

The guide wire of the present invention has been described above based on the illustrated embodiments, but the present invention is not limited to these. For example, the first wire A and the second wire B constituting the wire body may be composed of either solid members or hollow members, and the constituent materials thereof are the above-mentioned superelastic alloy or piano. Other than metallic materials such as wire, stainless steel, and tungsten, polyimide, polyester,
It may be made of various resin materials such as polyolefin (polypropylene, polyethylene), fluororesin, polyurethane and the like. Further, the wire main body may be composed of a laminated body in which a plurality of layers having different materials or physical properties are laminated.

[0078]

As described above, according to the guide wire of the present invention, the slit is formed at the position closer to the tip end than the boundary portion between the first wire and the second wire of the connecting member. Thereby, the rigidity of the connecting member can be continuously changed.

In particular, if the slits are formed so as to become denser toward the tip of the connecting member, the rigidity is increased from the tip of the first wire to the boundary between the first wire and the second wire. It can be increased continuously.

Further, the second wire is made of a metal material having a rigidity higher than that of the first wire, and the connecting member is made of the same or similar material as the second wire, so that the connecting member has a gradient in rigidity. If given, the rigidity can be continuously increased from the first wire toward the second wire.

Further, the first wire is made of a super elastic metal and the second wire is made of stainless steel, so that it has a tip portion excellent in flexibility and a base end portion rich in rigidity, A guide wire whose rigidity changes gently can be configured.

Further, the first wire and the connecting member, and
By fixing the second wire and the connecting member by welding, respectively, the binding force between the first wire and the second wire can be strengthened. In this case, excellent weldability can be obtained by selecting the materials of both wires and the connecting member.

Further, if the connecting end surface of the first wire and the second wire has a predetermined angle with respect to the surface having the axes of both wires as the normal line, the rigidity change at the boundary portion can be prevented. It is possible to further relax and further strengthen the bonding force between the first wire and the second wire.

In this way, according to the present invention, the difference in rigidity between the first wire and the second wire is selected by selecting a suitable tubular connecting member and forming a desired slit in the connecting member. Thus, it is possible to disperse the stress by converting into a large number of small rigidity differences in the connecting member. That is,
INDUSTRIAL APPLICABILITY The present invention can provide a guide wire that can smoothly transfer mechanical energy from the proximal end portion to the distal end portion and is excellent in operability and kink resistance.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of a guide wire of the present invention.

FIG. 2 is an explanatory view showing an example of a slit provided in a guide wire connecting member of the present invention.

FIG. 3 is an explanatory diagram showing an example of a guide wire connection method of the present invention.

FIG. 4 is an explanatory diagram showing bending stiffness measurement points.

FIG. 5 is a graph showing a bending rigidity measurement result.

FIG. 6 is a schematic diagram for explaining an example of use of the guide wire of the present invention.

FIG. 7 is a schematic diagram for explaining an example of use of the guide wire of the present invention.

[Explanation of symbols]

1 guide wire 111 Tip 112 X-ray contrast material 113 coating 12 Connection member 121 Encapsulation 122 opening 123 opening 124 border 131 Hand part (base) 2 balloon catheter 3 guiding catheter 4 aortic arch 5 Right coronary artery 6 Right coronary artery opening 7 Blood vessel stenosis 10 guide wire 20 adhesive 21 balloon A first wire B Second wire θ angle

Front page continued (58) Fields surveyed (Int.Cl. ⁷ , DB name) A61B 1/00-1/32 A61M 25/01

Claims (6)

(57) [Claims] 1. A flexible first member disposed on the distal end side.
A second wire having a rigidity higher than that of the first wire, the second wire being disposed on the base end side of the first wire, and the second wire having a tubular shape for connecting the first wire and the second wire. A connecting member, wherein the connecting member has a slit formed at a position closer to a tip end than a boundary portion between the first wire and the second wire, the slit having a function of reducing rigidity of the connecting member. A guide wire characterized in that 2. A flexible first member disposed on the distal end side.
A second wire having a rigidity higher than that of the first wire, the second wire being disposed on the base end side of the first wire, and the second wire having a tubular shape for connecting the first wire and the second wire. A connecting member, wherein the connecting member is formed with a slit having a function of reducing rigidity of the connecting member at a position closer to a tip end side than a boundary portion between the first wire and the second wire, A guide wire, wherein the rigidity of the first wire in the vicinity of the proximal end portion is configured to continuously change along the longitudinal direction of the wire. 3. The guide wire according to claim 1, wherein the slits are formed so as to become denser toward the distal end direction of the connection member. 4. The second wire is made of a metal material, and the connecting member is made of the same material as or a material similar to that of the second wire. Guide wire. 5. The guide wire according to claim 4, wherein the first wire is made of a super-elastic metal, and the second wire is made of stainless steel. 6. A connecting end surface between the first wire and the second wire is inclined at a predetermined angle with respect to a surface having a normal line to the axes of the both wires. The guide wire according to any one of 1 to 5.