JP5572378B2 - Guide wire - Google Patents

Description

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

  Guidewires are used for guiding catheters in difficult-to-surgical sites or treatment / inspections aimed at minimally invasive human bodies, such as PTCA (Percutaneous Transluminal Coronary Angioplasty) Used. Of these, the guide wire used in PTCA is inserted into the catheter prior to insertion of the catheter into the blood vessel, and the distal end of the guide wire together with the catheter is placed near the target vascular stenosis so that the distal end of the guide wire precedes. Used to guide up to. The distal end portion of this catheter has various shapes depending on the purpose of use and the site of use, and has the flexibility to follow complex bends in blood vessels and the body.

  Therefore, the guide wire used when inserting such a catheter into the blood vessel and the body has moderate flexibility, pushability and torque transmission for transmitting the operation at hand at the proximal end to the distal end (these Are generally referred to as “operability”), and further kink resistance (bending resistance) is required. In order to satisfy such a requirement, a guide wire in which a Ni—Ti alloy wire and a stainless wire are connected is known (for example, see Patent Document 1).

  However, since the Ni—Ti alloy wire and the stainless steel wire have different rigidity, the curvature radius of the Ni—Ti alloy wire and the stainless wire becomes different when the guide wire is entirely curved. For this reason, a phenomenon in which the welded portion of the Ni—Ti alloy wire and the stainless steel wire is bent rarely occurs, and in this case, the portion is likely to come into contact with the inner wall of the blood vessel. Sex is reduced.

JP 2006-325687 A

  An object of the present invention is to provide a guide wire excellent in operability.

Such an object is achieved by the present inventions (1) to (13) below.
(1) A guide wire used by being inserted into a blood vessel,
A linear first wire disposed on the distal end side, and a linear second wire disposed on a proximal end side of the first wire and made of a material having a larger elastic modulus than a constituent material of the first wire; A wire body having a welded portion welded to the first wire and the second wire;
A weld cover layer provided to cover at least the outer periphery of the weld;
A tip side coating layer provided on the tip side of the welded portion coating layer so as to cover at least a part of the first wire ;
A proximal end side coating layer provided to cover at least a part of the second wire on the proximal end side of the welded portion coating layer;
The second wire includes a first outer diameter constant portion having a constant outer diameter along the longitudinal direction from the proximal end side, an outer diameter gradually decreasing portion in which the outer diameter gradually decreases in the distal direction, and an outer diameter. Having a second outer diameter constant portion smaller than the first outer diameter constant portion and constant along the longitudinal direction,
A boundary portion between the base end side coating layer and the welded portion coating layer is located at a boundary between the second outer diameter constant portion and the outer diameter gradually decreasing portion of the second wire;
The outer diameter of the first outer diameter constant portion of the second wire is larger than the outer diameter of the welded portion,
The welding part coating layer is a layer whose surface has a lower sliding resistance than the surface of the tip side coating layer,
When the guide wire is inserted into the blood vessel and moved to the target site by pushing the guide wire, the radius of curvature of the first wire has a higher elastic modulus than the first wire. As a result, when the vicinity of the welded portion is bent, the vicinity of the welded portion becomes a portion that easily comes into contact with the inner wall of the blood vessel, and the welded portion coating layer is formed on the corresponding inner wall. A guide wire characterized in that the sensation of the distal end portion of the guide wire is transmitted to the proximal end side by sliding resistance generated when the distal end side coating layer slides against the inner wall of the blood vessel while sliding smoothly. .
(2) When the movement of the guide wire in the blood vessel is stopped, the distal end side coating layer makes the position of the distal end portion of the guide wire constant by bringing the distal end side coating layer into contact with the inner wall of the blood vessel. The guide wire as set forth in (1), wherein

(3) The guide wire according to (1) or (2) , wherein the weld portion coating layer is made of a material different from that of the tip side coating layer.

(4) The guide wire according to any one of (1) to (3), wherein the welded portion coating layer is mainly composed of a hydrophilic material.

(5) The guide wire according to any one of (1) to (3), wherein the welded portion coating layer is mainly composed of a hydrophobic material.

(6) surface prior Symbol weld coating layer, the guide wire according to any one of low (1) to sliding resistance than the surface of the proximal-side cover layer (5).

(7) The guide wire according to (6) , wherein the surface of the distal end side coating layer has a sliding resistance lower than that of the surface of the proximal end side coating layer.
(8) When the guide wire is inserted into the blood vessel and moved to the target site by pushing in the guide wire, the proximal-side covering layer is the guide at hand of the operator who performs the moving operation. The guide wire according to (7), which prevents slipping with respect to the wire.
(9) The guide wire according to (8), wherein the proximal-side coating layer maintains the guide wire at the stop position when the movement of the guide wire in the blood vessel is stopped.

(10) The welded portion of the first wire and the second wire, to any one of (1) to which a curved convex shape projecting toward the proximal direction of the wire body (9) Guide wire as described.

(11) The guide wire according to any one of (1) to (10) , wherein the first wire is made of a Ni—Ti alloy, and the second wire is made of stainless steel.

(12) The guide wire according to any one of (1) to (11) , wherein the welded portion coating layer has a plurality of convex portions.

(13) The guide wire according to (12) , wherein the convex portion has a hemispherical shape.

  According to the present invention, since the outer periphery of the weld portion of the first wire and the second wire, which is a portion where kinks are relatively likely to occur, is covered with the weld portion coating layer having low slidability, the guide wire is placed inside the blood vessel. Even if the kink is generated near the weld when moved, and the vicinity of the weld contacts the inner wall of the blood vessel, the weld coating layer smoothly slides against the inner wall of the blood vessel. The operability is excellent.

It is a longitudinal cross-sectional view which shows 1st Embodiment of the guide wire of this invention. It is a figure which shows the procedure which connects the 1st wire and 2nd wire in the guide wire shown in FIG. It is a figure of the state which curved the guide wire shown in FIG. It is a figure which shows the use condition at the time of using the guide wire of this invention for PTCA operation. It is a figure which shows the use condition at the time of using the guide wire of this invention for PTCA operation. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the guide wire of this invention. It is a longitudinal cross-sectional view which shows 3rd Embodiment of the guide wire of this invention.

  Hereinafter, a preferred embodiment of the guide wire of the present invention will be described with reference to the accompanying drawings.

<First Embodiment>
First, a first embodiment of the guide wire of the present invention will be described.

  FIG. 1 is a longitudinal sectional view showing a first embodiment of the guide wire of the present invention, FIG. 2 is a diagram showing a procedure for connecting the first wire and the second wire in the guide wire shown in FIG. 1, and FIG. FIG. 4 is a view showing a state in which the guide wire shown in FIG. 1 is bent, and FIGS. 4 and 5 are views showing a use state when the guide wire of the present invention is used in PTCA surgery. For convenience of explanation, the right side in FIGS. 1 and 2 is referred to as “base end”, and the left side is referred to as “tip”. Further, in FIG. 1 and FIG. 2, the length direction of the guide wire is shortened and the thickness direction of the guide wire is exaggerated for the sake of clarity. The ratio is very different from the actual ratio (the same applies to FIGS. 3 to 5 described later).

  A guide wire 1 shown in FIG. 1 includes a first wire 2 disposed on a distal end side, a second wire 3 disposed on a proximal end side of the first wire 2, and welding of the first wire 2 and the second wire 3. A wire main body 10 having a portion 4, a welded portion coating layer 5 formed so as to cover the outer periphery of the welded portion 4 of the first wire 2 and the second wire 3, and a position closer to the tip than the welded portion coating layer 5 And a distal end side covering layer 6 formed so as to cover the outer periphery of the first wire 2, and a base formed so as to cover the outer periphery of the second wire 3, which is located on the base end side with respect to the welded portion covering layer 5. And an end-side coating layer 7.

  The total length of the guide wire 1 is not particularly limited, but is preferably about 200 to 5000 mm. Further, the outer diameter of the thickest part of the wire body 10 (that is, the part where the outer diameter of the second wire 3 is constant) is not particularly limited, but is usually preferably about 0.2 to 1.2 mm. .

  The first wire 2 is an elastic wire. Although the length of the 1st wire 2 is not specifically limited, It is preferable that it is about 20-1000 mm.

  In the present embodiment, the first wire 2 has a first outer diameter constant portion 21 whose outer diameter is constant along the longitudinal direction from the proximal end side, and an outer diameter whose outer diameter gradually decreases in the distal direction. A gradually decreasing portion 22 and a second outer diameter constant portion 23 having an outer diameter smaller than that of the first outer diameter constant portion 21 and constant along the longitudinal direction are provided. By having the outer diameter gradually decreasing portion 22, the rigidity (bending rigidity, torsional rigidity) of the first wire 2 can be gradually decreased toward the distal end direction. Flexibility is obtained, blood vessel followability and safety are improved, and bending and the like can be prevented.

  In the illustrated configuration, the outer diameter gradually decreasing portion 22 is formed on a part of the first wire 2, but the entire first wire 2 may constitute the outer diameter gradually decreasing portion 22. Further, the taper angle of the outer diameter gradually decreasing portion 22 (outer diameter reduction rate) may be constant along the longitudinal direction of the wire, or there may be a portion that varies along the longitudinal direction. For example, a portion in which a taper angle (an outer diameter reduction rate) and a relatively small portion are alternately formed a plurality of times may be used.

  In addition, the first wire 2 has, for example, tapered portions (outer diameter gradually decreasing portions) whose outer diameter gradually decreases in the distal direction, formed at a plurality of locations along the longitudinal direction, and these tapered portions and tapered portions. A portion in which the outer diameter is constant along the longitudinal direction may be used. Even in such a case, the same effect as described above can be obtained.

  Also, unlike the illustrated configuration, the proximal end of the outer diameter gradually decreasing portion 22 is located in the middle of the second wire 3, that is, the outer diameter gradually decreasing portion 22 is a boundary between the first wire 2 and the second wire 3 (welded portion 4 ) May be used.

  The constituent material of the 1st wire 2 is not specifically limited, For example, various metal materials, such as stainless steel, can be used, Among them, the alloy (a superelastic alloy is included) which shows pseudoelasticity especially among these. preferable. More preferably, it is a superelastic alloy. Since the superelastic alloy is relatively flexible, has a resilience, and is difficult to bend, the guide wire 1 can be sufficiently formed at the tip side by configuring the first wire 2 with the superelastic alloy. Flexibility and bendability can be obtained, followability to a complicatedly bent / bent blood vessel can be improved, more excellent operability can be obtained, and even if the first wire 2 repeats bending / bending deformation, Since the first wire 2 is not bent due to the resilience, it is possible to prevent the operability from being deteriorated due to the bending of the first wire 2 during use of the guide wire 1.

  Pseudoelastic alloys include any shape of stress-strain curve due to tension, including those that can measure the transformation point of As, Af, Ms, Mf, etc., and those that cannot be measured. However, everything that returns to its original shape by removing stress is included.

  The preferred composition of the superelastic alloy is Ni-Ti alloy such as Ni-Ti alloy of 49-52 atomic% Ni, Cu-Zn alloy of 38.5-41.5 wt% Zn, 1-10 wt% X Cu-Zn-X alloy (X is at least one of Be, Si, Sn, Al, and Ga), 36-38 atomic% Al-Ni-Al alloy, and the like. Of these, the Ni-Ti alloy is particularly preferable. In addition, the superelastic alloy represented by the Ni-Ti type alloy is excellent also in the adhesiveness of the welding part coating layer 5 and the front end side coating layer 6 mentioned later.

  The distal end of the second wire 3 is connected (connected) to the proximal end of the first wire 2 by welding. The second wire 3 is an elastic wire. Although the length of the 2nd wire 3 is not specifically limited, It is preferable that it is about 20-4800 mm.

  In the present embodiment, the second wire 3 includes a first outer diameter constant portion 31 having a constant outer diameter along the longitudinal direction and an outer diameter in which the outer diameter gradually decreases in the distal direction from the proximal end side. A gradually decreasing portion 32 and a second outer diameter constant portion 33 having an outer diameter smaller than that of the first outer diameter constant portion 31 and constant along the longitudinal direction are provided. By having the outer diameter gradually decreasing portion 32, the rigidity (bending rigidity, torsional rigidity) of the second wire 3 can be gradually decreased toward the distal end direction. As a result, the guide wire 1 has excellent operability. Demonstrate.

  In the illustrated configuration, the second wire 3 has the outer diameter gradually decreasing portion 32, but the outer diameter gradually decreasing portion 32 may be omitted. That is, the outer diameter of the second wire 2 may be substantially constant along the longitudinal direction except for the rounded proximal end portion.

  Such a second wire 3 is made of a material having a higher elastic modulus (Young's modulus (longitudinal elastic modulus), rigidity (transverse elastic modulus), and bulk elastic modulus) than the constituent material of the first wire 2. Thereby, moderate rigidity (bending rigidity, torsional rigidity) is obtained for the second wire 3, the guide wire 1 becomes so-called strong and the pushability and torque transmission performance are improved, and more excellent insertion operability. Is obtained.

  The constituent material (material) of the second wire 3 is not particularly limited, and stainless steel (for example, SUS304, SUS303, SUS316, SUS316L, SUS316J1, SUS316J1L, SUS405, SUS430, SUS434, SUS444, SUS429, SUS430F, SUS302, etc. All types), various metal materials such as piano wire, cobalt-based alloy, and pseudoelastic alloy can be used. Among these, stainless steel is particularly preferable. When stainless steel is used, the guide wire 1 can obtain better pushability and torque transmission.

  Here, in the present invention, the first wire 2 and the second wire 3 are preferably made of different alloys, and the first wire 2 is made of a material having a smaller elastic modulus than the constituent material of the second wire 3. Yes. As a result, the guide wire 1 has excellent flexibility at the distal end portion and abundant rigidity (bending rigidity, torsional rigidity) at the proximal end portion. As a result, the guide wire 1 obtains excellent pushability and torque transmission and secures good operability, while obtaining good flexibility and restoration on the distal end side, followability to blood vessels, and safety. Will improve.

  As a specific combination of the first wire 2 and the second wire 3, it is particularly preferable that the first wire 2 is made of a Ni—Ti alloy and the second wire 3 is made of stainless steel. Thereby, the effect mentioned above becomes further remarkable.

  The first wire 2 and the second wire 3 as described above are connected (fixed) to each other by welding. As a result, the welded portion 4 between the first wire 2 and the second wire 3 has a high bonding strength (joining strength), and thus the guide wire 1 has a reliable torsional torque and pushing force from the second wire 3. Is transmitted to the first wire 2.

  Moreover, it is preferable that the outer peripheral part of the welding part 4 is made substantially smooth, for example by methods, such as the procedure (3) mentioned later.

  In this embodiment, the connection end surface 24 of the first wire 2 with respect to the second wire 3 and the connection end surface 34 of the second wire 3 with respect to the first wire 2 are substantially perpendicular to the axial direction (longitudinal direction) of both wires. It is a flat surface. Thereby, the process for forming the connection end surfaces 24 and 34 is very easy, and the above-described effects can be achieved without complicating the manufacturing process of the guide wire 1.

  Note that, unlike the illustrated configuration, the connection end surfaces 24 and 34 may be inclined with respect to a plane perpendicular to the axial direction (longitudinal direction) of both wires, or may be concave or convex.

  The method for welding the first wire 2 and the second wire 3 is not particularly limited, and examples thereof include butt resistance welding such as spot welding using a laser and butt seam welding. Is preferred. Thereby, as for the welding part 4, higher bond strength is obtained.

  Hereinafter, with reference to FIG. 2, the procedure in the case of joining the 1st wire 2 and the 2nd wire 3 by butt seam welding which is an example of butt resistance welding is demonstrated. In the figure, procedures (1) to (3) in the case where the first wire 2 and the second wire 3 are joined by butt seam welding are shown.

  In the procedure (1), the first wire 2 and the second wire 3 fixed (mounted) to a butt welder (not shown) are shown.

  In step (2), the first wire 2 and the second wire 3 are connected to the proximal end side connection end surface 24 of the first wire 2 and the distal end of the second wire 3 while a predetermined voltage is applied by a butt welder. The contact end surface 34 on the side is brought into pressure contact. By this pressure contact, a molten layer is formed at the contact portion, and the first wire 2 and the second wire 3 are firmly connected.

  In the procedure (3), the protruding portion of the welded portion 4 deformed by the pressure contact is removed (deleted). Thereby, the outer periphery of the welding part 4 is made substantially smooth. In addition, as for the removal method of a protrusion part, chemical treatments, such as grinding, grinding | polishing, and etching, are mentioned, for example.

  In the wire body 10 formed in this way, a welded portion coating layer 5 is formed so as to cover the outer periphery of the welded portion 4. The purpose of forming the weld coating 5 is mainly to improve the operability of the guide wire 1 by reducing the friction (sliding resistance) near the weld 4 of the guide wire 1 and improving the slidability. This is to make it happen. Therefore, it is preferable that the welding part coating layer 5 is comprised with the material which can reduce friction.

  Here, as described above, the elastic modulus is different between the first wire 2 and the second wire 3 (the elastic modulus of the second wire 3 is larger than that of the first wire 2). Therefore, when the vicinity of the welded portion 4 of the guide wire 1 is curved, the radius of curvature of the first wire 2 becomes smaller than the radius of curvature of the second wire 3 as shown in FIG. The guide wire 1 is deformed so as to be bent at the portion 4 and its vicinity (hereinafter simply referred to as “the vicinity of the weld portion 4”) (that is, a kink is generated near the weld portion 4).

  When the guide wire 1 is inserted into the blood vessel and moved to the target site, for example, when the above-described deformation occurs by pushing the guide wire 1, the vicinity of the welded portion 4 contacts the inner wall of the blood vessel. Touch. In other words, when the guide wire 1 is moved to the target site, the vicinity of the welded portion 4 is likely to come into contact with the inner wall of the blood vessel as compared with other sites. Therefore, in the guide wire 1, the welded portion covering layer 5 is formed so as to cover at least the outer periphery of the welded portion 4, which is a portion that easily contacts the inner wall of the blood vessel. Is in contact with the inner wall of the blood vessel, the contact portion (near the welded portion 4) smoothly slides with respect to the inner wall of the blood vessel. Thereby, the guide wire 1 can exhibit excellent operability.

  The constituent material of the weld coating layer 5, that is, the material capable of reducing friction is not particularly limited, but is preferably a hydrophilic material or a hydrophobic material. Of these, hydrophilic materials are particularly preferable.

  Examples of hydrophilic materials include cellulose-based polymer materials, polyethylene oxide-based polymer materials, and maleic anhydride-based polymer materials (for example, maleic anhydride copolymers such as methyl vinyl ether-maleic anhydride copolymer). Acrylamide polymer substances (for example, polyacrylamide, polyglycidyl methacrylate-dimethylacrylamide (PGMA-DMAA) block copolymer), water-soluble nylon, polyvinyl alcohol, polyvinylpyrrolidone and the like.

  Such hydrophilic materials often exhibit lubricity by wetting (water absorption) and reduce frictional resistance (sliding resistance) with the inner wall of the blood vessel. Thereby, the slidability of the guide wire 1 (near the welded portion 4) with respect to the inner wall of the blood vessel is improved, and the operability of the guide wire 1 is further improved.

  On the other hand, examples of the hydrophobic material include polyamide, polyimide, polyurethane, polystyrene, silicone resin, fluorine-based resin (PTFE, ETFE, etc.), or a composite material thereof. Even when such a hydrophobic material is used, the same effect as that of the hydrophilic material described above can be exhibited.

  In the present embodiment, the weld portion coating layer 5 has the same outer diameter along the longitudinal direction of the guide wire 1. Therefore, the slidability of the guide wire 1 is further improved.

  The thickness of the welded portion coating layer 5 is not particularly limited, but usually the thickness (average) is preferably about 1 to 20 μm, and more preferably about 2 to 10 μm. If the thickness of the welded portion coating layer 5 is too thin, the purpose of forming the welded portion coating layer 5 may not be sufficiently exhibited, and the welded portion coating layer 5 may be peeled off. On the contrary, if the thickness of the welded portion coating layer 5 is too thick, the physical properties of the guide wire 1 (wire body 10) may be hindered, and the welded portion coating layer 5 may be peeled off.

  In the present invention, the outer peripheral surface (surface) of the wire body 10 is subjected to a treatment (chemical treatment, heat treatment, etc.) for improving the adhesion of the weld coating layer 5 or the adhesion of the weld coating layer 5. It is also possible to provide an intermediate layer (binder layer) that can improve the above. Moreover, you may form the welding part coating layer 5 from two or more layers.

  A distal end side coating layer 6 is formed on the distal end side of the welded portion coating layer 5. The purpose of forming the distal end side coating layer 6 is, for example, to alleviate a change in outer diameter on the distal end side of the wire body 10. It can also be provided for the purpose of improving safety when the guide wire 1 is inserted into a blood vessel or the like. For such a purpose, it is preferable that the front end side coating layer 6 is made of a flexible material (soft material, elastic material).

  As a constituent material of the front end side coating layer 6, that is, a material rich in flexibility, for example, polyolefin such as polyethylene and polypropylene, polyvinyl chloride, polyester (PET, PBT, etc.), polyamide, polyimide, polyurethane, polystyrene, silicone resin, Examples thereof include thermoplastic elastomers such as polyurethane elastomers, polyester elastomers and polyamide elastomers, various rubber materials such as latex rubber and silicone rubber, or composite materials obtained by combining two or more of these.

  In the present embodiment, the distal end side coating layer 6 is provided so as to cover the entire region on the distal end side with respect to the welded portion coating layer 5 of the wire body 10. Thereby, the safety | security at the time of inserting the guide wire 1 in the blood vessel etc. can be improved more.

  Further, the distal end side coating layer 6 is formed so that the outer diameter thereof is substantially constant along the longitudinal direction of the guide wire 1. Therefore, the outer diameter change on the distal end side of the wire body 10 can be eliminated, and the operability of the guide wire 1 is further improved.

  Further, the distal end side coating layer 6 is in contact with the distal end side of the welded portion coating layer 5 on the proximal end side. That is, there is no portion where the wire body 10 is exposed between the distal end side coating layer 6 and the welded portion coating layer 5. Thereby, the operativity of the guide wire 1 further improves. In particular, since the surface of the front end side coating layer 6 and the surface of the welded portion coating layer 5 are connected without a step, the above-described effect becomes more remarkable.

  Moreover, the contrast agent which consists of metal powder (metal particle) which has X-ray contrast property may be added to the site | part located in the front-end | tip part of the guide wire 1 of the front end side coating layer 6. FIG. The metal material is not particularly limited, and examples thereof include noble metals such as tungsten, gold, and platinum, and tungsten is particularly preferable. Accordingly, when the guide wire 1 is inserted into a target site of a living body lumen such as a blood vessel under fluoroscopy, the position of the distal end portion of the guide wire 1 is surely grasped in the living body lumen. be able to.

  In the present embodiment, the boundary portion between the distal end side coating layer 6 and the welded portion coating layer 5 is located at the first outer diameter constant portion 21 of the first wire 2. The position of the boundary part with the part coating layer 5 is not limited to this, and may be located, for example, in the outer diameter gradually decreasing part 22 or in the second outer diameter constant part 23. Further, it may be located at the boundary between the first outer diameter constant portion 21 and the outer diameter gradually decreasing portion 22, or may be positioned at the boundary between the outer diameter gradually decreasing portion 22 and the second outer diameter constant decreasing portion 23. .

  Moreover, in this embodiment, although the front-end | tip side coating layer 6 is contacting so that the surface may not form a level | step difference with the surface of the welding part coating layer 5, it is not limited to this, The surface is a welding part coating layer. 5 and a step may be formed. Furthermore, in this case, the surface of the front end side coating layer 6 may be located outside the surface of the welded part coating layer 5 or may be located inside.

  Moreover, in this embodiment, although the front end side coating layer 6 and the welding part coating layer 5 are contacting, it is not limited to this, Even if the front end side coating layer 6 and the welding part coating layer 5 are spaced apart, Good. That is, there may be a portion where the wire body 10 (first wire 2) is exposed between the distal end side coating layer 6 and the welded portion coating layer 5.

  Further, the outer peripheral surface (surface) of the wire body 10 can be subjected to a treatment (chemical treatment, heat treatment, etc.) for improving the adhesion of the distal end side coating layer 6 or the adhesion of the distal end side coating layer 6 can be improved. An intermediate layer (binder layer) can also be provided. Moreover, you may form the front end side coating layer 6 from two or more layers.

  On the other hand, a proximal end side covering layer 7 is formed on the proximal end side of the welded portion covering layer 5. The purpose of forming the proximal end side coating layer 7 is the same as the purpose of forming the distal end side coating layer 6. Therefore, as the constituent material of the base end side coating layer 7, the materials mentioned as the constituent material of the distal end side coating layer 6 can be used.

  Such a base end side coating layer 7 is in contact with the base end side of the welded portion coating layer 5 at the tip side. That is, there is no portion where the wire body 10 is exposed between the base end side coating layer 7 and the welded portion coating layer 5. Thereby, the operativity of the guide wire 1 further improves. In particular, since the surface of the base end side coating layer 7 and the surface of the welded portion coating layer 5 are connected without a step, the above-described effect becomes more remarkable.

  In the present embodiment, the boundary portion between the base end side coating layer 7 and the welded portion coating layer 5 is located at the boundary between the second outer diameter constant portion 33 and the outer diameter gradually decreasing portion 32 of the second wire 3. However, the position of the boundary portion between the base end side coating layer 7 and the welded portion coating layer 5 is not limited to this, and may be located, for example, in the second outer diameter constant portion 33, or the outer diameter gradually decreases. It may be located in the part 32 or may be located in the first constant outer diameter part 31. Further, it may be located at the boundary between the first outer diameter constant portion 31 and the outer diameter gradually decreasing portion 32.

  In this embodiment, the base end side coating layer 7 and the welded portion coating layer 5 are in contact with each other. However, the present invention is not limited to this, and the base end side coating layer 7 and the welded portion coating layer 5 are separated from each other. May be. That is, there may be a portion where the wire main body 10 (second wire 3) is exposed between the base end side coating layer 7 and the welded portion coating layer 5.

  Further, the outer peripheral surface (surface) of the wire body 10 is subjected to a treatment (chemical treatment, heat treatment, etc.) for improving the adhesion of the proximal end side coating layer 7 or the adhesion of the proximal end side coating layer 7 is improved. An intermediate layer (binder layer) can be provided. Moreover, you may form the base end side coating layer 7 from two or more layers.

  The three coating layers, that is, the weld coating layer 5, the distal-side coating layer 6, and the proximal-side coating layer 7 have been described above. In the present invention, among these three coating layers, the sliding resistance of the surface of the weld coating layer 5 is that of the other two coating layers (that is, the distal-side coating layer 6 and the proximal-side coating layer 7). Lower than the sliding resistance of the surface. Thereby, the following effects are obtained. In the following, the fact that the sliding resistance is relatively higher than the other layers is simply referred to as “high”, and conversely, the fact that the sliding resistance is relatively lower than the other layers is also simply referred to as “low”.

  First, since the welded portion coating layer 5 having low sliding resistance is formed so as to cover the outer periphery of the welded portion 4 that is a portion that easily contacts the inner wall of the blood vessel, as described above, the welded portion 4 of the guide wire 1 is formed. Even when the vicinity is in contact with the inner wall of the curved portion of the blood vessel and a strong push is received from the hand side, the occurrence of kinks can be reliably prevented. Therefore, both the operability and safety of the guide wire 1 can be improved.

  Secondly, since the distal end side coating layer 6 having a high sliding resistance is formed so as to cover the distal end portion of the wire body 10, the sense of the distal end portion of the guide wire 1 can be accurately transmitted to the surgeon. More specifically, when the sliding resistance of the surface of the distal end side coating layer 6 is equal to or lower than the sliding resistance of the surface of the weld coating layer 5, for example, the distal end portion of the guide wire 1 is a blood vessel. Since it slides smoothly with respect to the inner wall (that is, friction hardly occurs), it is difficult for the operator to feel the sense of the distal end portion of the guide wire 1. On the other hand, in the present invention, since the sliding resistance of the surface of the distal end side coating layer 6 is high, appropriate friction is generated when the distal end portion slides against the inner wall of the blood vessel, and the guide wire is caused by the friction. The sense of the tip of 1 is accurately conveyed to the surgeon. Here, the sliding resistance on the surface of the distal end-side coating layer 6 may be such that there is no possibility of damaging a tissue such as an inner wall of a blood vessel due to sliding (friction generated by sliding). Thereby, said effect can be exhibited, ensuring safety | security.

  Thirdly, the guide wire 1 has a role of guiding the catheter to the target site. Therefore, it is important to keep the position of the distal end portion of the guide wire 1 constant until the catheter is guided to the target site. This is because if the position of the distal end portion of the guide wire 1 is shifted in the insertion direction, the catheter will penetrate too far into the target site, and if the catheter is shifted to the opposite side in the insertion direction, This is because the target part cannot be reached. Therefore, in the present invention, the distal end side coating layer 6 having a high sliding resistance is formed at the distal end portion of the guide wire 1, and the distal end side coating layer 6 is brought into contact with the inner wall of the blood vessel, so that a slight amount therebetween. A frictional force is generated so that it is easy to keep the position of the tip of the guide wire 1 constant. Thereby, the guide wire 1 can exhibit the outstanding operativity (catheter guide property).

  Here, in order to make the sliding resistance of the surface of the welding portion coating layer 5 lower than the sliding resistance of the surfaces of the other two coating layers (that is, the tip side coating layer 6 and the base end side coating layer 7). The constituent material of the weld coating layer 5 is preferably different from the constituent material of the distal end side coating layer 6 (base end side coating layer 7). Thereby, since the sliding resistance of the surface of the welding part coating layer 5 can be made lower than the sliding resistance of the surface of two other coating layers by selecting a constituent material suitably, a welding part coating layer is obtained. 5. Formation of the front end side coating layer 6 and the proximal end side coating layer 7 is facilitated.

  Furthermore, as a specific combination of the constituent materials of the welded portion coating layer 5, the distal end side coating layer 6 and the proximal end side coating layer 7, for example, the welded portion coating layer 5 is made of a hydrophilic material, and the distal end side coating layer is formed. 6 is made of a hydrophilic material having a sliding resistance higher than that of silicone or a weld coating layer, and the base-side coating layer 7 has a higher sliding resistance than the tip-side coating layer 6 (for example, PTFE). , ETFE, etc.).

  Further, by roughening the surfaces of the distal end side covering layer 6 and the proximal end side covering layer 7, the sliding resistance of the surface of the welded portion covering layer 5 is made lower than the sliding resistance of the surfaces of the other two covering layers. May be.

  As described above, it has been described that the sliding resistance of the surface of the welded portion coating layer 5 is lower than the sliding resistance of the surfaces of the other two coating layers (that is, the distal end side coating layer 6 and the proximal end side coating layer 7). However, the relationship of (sliding resistance of the surface of the weld coating layer 5) <(sliding resistance of the surface of the distal end side coating layer 6) <(sliding resistance of the surface of the proximal side coating layer 7) is satisfied. Satisfaction is preferred. That is, among the three coating layers 5, 6, and 7, it is preferable that the sliding resistance of the surface of the welded portion coating layer 5 is the lowest and the sliding resistance of the surface of the base end side coating layer 7 is the highest. Thereby, in addition to the effects described above, the following effects can be exhibited. That is, by making the sliding resistance of the surface of the base end side coating layer 7 the highest, the operator can hold (manipulate) the guide wire 1 firmly without the hand slipping on the base end side. In addition, even if the surgeon releases the guide wire 1, the guide wire 1 does not slide down, and an anchor effect that maintains the state (position) as it is can be exhibited. Thus, by making the sliding resistance of the surface of the base end side coating layer 7 the highest, both safety and operability of the guide wire 1 can be further improved.

  FIG. 4 and FIG. 5 are diagrams each showing a use state when the guide wire 1 of the present invention is used in PTCA surgery.

  4 and 5, reference numeral 40 denotes an aortic arch, reference numeral 50 denotes a right coronary artery of the heart, reference numeral 60 denotes a right coronary artery opening, and reference numeral 70 denotes a vascular stenosis. Reference numeral 30 is a guiding catheter for reliably guiding the guide wire 1 from the femoral artery to the right coronary artery, and reference numeral 20 is a balloon catheter for constriction portion expansion having a balloon 201 that can be expanded and contracted at its distal end. .

  As shown in FIG. 4, the distal end of the guide wire 1 is projected from the distal end of the guiding catheter 30 and inserted into the right coronary artery 50 through the right coronary artery opening 60. Further, the guide wire 1 is advanced and inserted into the right coronary artery from the distal end, and stopped at a position where the distal end exceeds the vascular stenosis 70. Thereby, the passage of the balloon catheter 20 is secured. At this time, the welded portion 4 of the guide wire 1 is located at the aortic arch 40 or in the vicinity thereof (in vivo).

  Next, as shown in FIG. 5, the distal end of the balloon catheter 20 inserted from the proximal end side of the guide wire 1 is protruded from the distal end of the guiding catheter 30 and further advanced along the guide wire 1 to open the right coronary artery opening. It is inserted into the right coronary artery 50 from the part 60 and stops when the balloon reaches the position of the vascular stenosis part 70.

  Next, a balloon expansion fluid is injected from the proximal end side of the balloon catheter 20 to expand the balloon 201 and expand the vascular stenosis part 70. By doing in this way, deposits, such as cholesterol deposited on the blood vessel of the blood vessel stenosis part 70, are physically expanded, and blood flow obstruction can be eliminated.

Second Embodiment
Next, a second embodiment of the guide wire of the present invention will be described.

  FIG. 6 is a longitudinal sectional view showing a second embodiment of the guide wire of the present invention. For convenience of explanation, the right side in FIG. 6 is referred to as “base end”, and the left side is referred to as “tip”.

  Hereinafter, the guide wire 1 </ b> A illustrated in FIG. 6 will be described. However, the difference from the guide wire 1 of the first embodiment will be mainly described, and the description of the same matters will be omitted.

  The guide wire 1A of the present embodiment is the same as the guide wire 1 of the first embodiment except that the shapes of the welded portions of the first wire and the second wire are different.

  The weld 4A of the second wire 3A of the first wire 2A has a curved surface shape. Specifically, it forms a curved convex surface (dish shape) that is convex toward the proximal direction of the wire body 10A. In addition, the curved surface of the welded portion 4A has a substantially symmetric shape with respect to the central axis of the wire body 10A. That is, the curved surface of the welded portion 4A has a rotating body shape centered on the central axis of the wire body 10A. The rotating body shape of the welded portion 4A includes, for example, a spherical shape, a paraboloid shape, or a shape similar to these in addition to a dish shape.

  Since the welded portion 4A has such a shape, the following effects can be obtained. That is, since the welded portion 4A has a curved surface shape, the bonding area becomes larger than that of the flat surface, and the effect of dispersing stress with respect to bending is produced, so that high bonding strength can be obtained. Further, since the curved surface of the welded portion 4A is symmetrical with respect to the central axis of the wire body 10A, when the wire body 10A is twisted, the torque is uniformly distributed from the second wire 3A to the first wire 2A. Can be transmitted (without bias). This contributes to improving the operability of the guide wire 1A.

<Third Embodiment>
Next, a third embodiment of the guide wire of the present invention will be described.
FIG. 7 is a longitudinal sectional view showing a third embodiment of the guide wire of the present invention.

  Hereinafter, the guide wire 1B shown in FIG. 7 will be described, but the description will focus on differences from the guide wire 1 of the first embodiment, and description of similar matters will be omitted.

  The guide wire 1B of this embodiment is the same as the guide wire 1 of the first embodiment except that the configuration of the weld coating layer is different.

  As shown in FIG. 7, the weld portion covering layer 5B has a plurality of convex portions 51B that protrude in the outer peripheral direction of the guide wire 1B. Each convex portion 51B has a substantially hemispherical shape. In other words, the weld portion coating layer 5B is configured by arranging a plurality of substantially hemispherical convex portions 51B without any gaps.

  The plurality of convex portions 51B may be arranged in a matrix (regular) or irregularly. The plurality of convex portions 51B may be the same size or different from each other, but preferably have the same size.

  Further, for example, the welding portion coating layer 5B may be partitioned into a plurality of regions along the longitudinal direction of the guide wire 1B, and the size of the convex portion 51B may be varied for each partitioned region. For example, the first region including the outer periphery of the welded portion 4, the second region located on the proximal end side thereof, and the third region located on the distal end side are partitioned, and the size of the convex portion 51 </ b> B located in the second region. And the convex portion 51B located in the third region are the same, and the size of the convex portion 51B located in the first region is larger than the size of the convex portion 51B located in the second and third regions. Good.

  According to such a welding part coating layer 5B, the following effects can be exhibited. That is, as described above, the vicinity of the welded portion 4 is a portion where kinks are relatively likely to occur. Therefore, relatively large expansion occurs at a position outside the kink direction of the weld coating layer 5B, and relatively large expansion / contraction occurs at a position inside the kink direction. By configuring the welded portion coating layer 5B as in the present embodiment, it is possible to exhibit excellent followability with respect to the deformation of the wire body 10, and prevent damage due to expansion, generation of wrinkles due to expansion and contraction, and the like. Or it can be suppressed. Therefore, the reliability and operability of the guide wire 1 are improved.

  In addition, although this embodiment demonstrated the form in which the welding part coating layer 5B has the some convex part 51B, it replaced with the some convex part 51B, and the some cyclic | annular (ring) whose cross-sectional shape is substantially hemispherical shape. Convex shape may be used. That is, a plurality of annular projections formed along the circumferential direction are continuously provided on the outer periphery of the wire body 10 without gaps along the longitudinal direction of the wire body 10, thereby forming the weld coating layer 5 </ b> B. May be. Even with such a configuration, the same effects as those of the convex portion 51B can be exhibited.

  Moreover, although this embodiment demonstrated the form in which the some convex part 51B was arrange | positioned without gap, it is not limited to this, For example, the adjacent convex parts 51B are spaced apart and the wire main body 10 is exposed from there. You may do it.

  The guide wire of the present invention has been described above with respect to the illustrated embodiments. However, the present invention is not limited to these embodiments, and each part of the guide wire has an arbitrary configuration that can exhibit the same function. Can be substituted for Moreover, arbitrary components may be added. Moreover, each embodiment can also be combined suitably.

1, 1A, 1B Guide wire 10, 10A Wire body 2, 2A First wire 21 First outer diameter constant portion 22 Outer diameter gradually decreasing portion 23 Second outer diameter constant portion 24 Connection end surface 3, 3A Second wire 31 First outer Constant diameter part 32 Outer diameter gradually decreasing part 33 Second outer diameter constant part 34 Connection end surface 4, 4A Welded part 5, 5B Welded part covering layer 51B Convex part 6 Front end side covering layer 7 Base end side covering layer 20 Balloon catheter 201 Balloon 30 Guiding catheter 40 Aortic arch 50 Right coronary artery 60 Right coronary artery opening 70 Vascular stenosis

Claims (13)

A guide wire used by being inserted into a blood vessel,
A linear first wire disposed on the distal end side, and a linear second wire disposed on a proximal end side of the first wire and made of a material having a larger elastic modulus than a constituent material of the first wire; A wire body having a welded portion welded to the first wire and the second wire;
A weld cover layer provided to cover at least the outer periphery of the weld;
A tip side coating layer provided on the tip side of the welded portion coating layer so as to cover at least a part of the first wire ;
A proximal end side coating layer provided to cover at least a part of the second wire on the proximal end side of the welded portion coating layer;
The second wire includes a first outer diameter constant portion having a constant outer diameter along the longitudinal direction from the proximal end side, an outer diameter gradually decreasing portion in which the outer diameter gradually decreases in the distal direction, and an outer diameter. Having a second outer diameter constant portion smaller than the first outer diameter constant portion and constant along the longitudinal direction,
A boundary portion between the base end side coating layer and the welded portion coating layer is located at a boundary between the second outer diameter constant portion and the outer diameter gradually decreasing portion of the second wire;
The outer diameter of the first outer diameter constant portion of the second wire is larger than the outer diameter of the welded portion,
The welding part coating layer is a layer whose surface has a lower sliding resistance than the surface of the tip side coating layer,
When the guide wire is inserted into the blood vessel and moved to the target site by pushing the guide wire, the radius of curvature of the first wire has a higher elastic modulus than the first wire. As a result, when the vicinity of the welded portion is bent, the vicinity of the welded portion becomes a portion that easily comes into contact with the inner wall of the blood vessel, and the welded portion coating layer is formed on the corresponding inner wall. A guide wire characterized in that the sensation of the distal end portion of the guide wire is transmitted to the proximal end side by sliding resistance generated when the distal end side coating layer slides against the inner wall of the blood vessel while sliding smoothly. .   The distal-side coating layer keeps the position of the distal end portion of the guide wire constant by bringing the distal-side coating layer into contact with the inner wall of the blood vessel when the movement of the guide wire in the blood vessel is stopped. Item 2. A guide wire according to item 1.   The guide wire according to claim 1, wherein the welded portion coating layer is made of a material different from that of the distal end side coating layer.   The guide wire according to any one of claims 1 to 3, wherein the welded portion coating layer is mainly composed of a hydrophilic material.   The guide wire according to any one of claims 1 to 3, wherein the weld coating layer is mainly made of a hydrophobic material. Surface prior Symbol weld coating layer, the guide wire according to any one of 5 to no less claim 1 sliding resistance than the surface of the proximal-side cover layer.   The guide wire according to claim 6, wherein the front-side coating layer has a lower sliding resistance than the surface of the proximal-side coating layer.   When the guide wire is inserted into the blood vessel and moved to the target site by pushing in the guide wire, the proximal-side covering layer slides against the guide wire at the hand of the operator who performs the moving operation. 8. The guide wire according to claim 7, wherein the guide wire is prevented.   The guide wire according to claim 8, wherein when the movement of the guide wire is stopped in the blood vessel, the proximal-side coating layer maintains the guide wire at the stop position.   The guide wire according to any one of claims 1 to 9, wherein the welded portion of the first wire and the second wire has a curved convex shape that is convex toward the proximal direction of the wire body.   The guide wire according to any one of claims 1 to 10, wherein the first wire is made of a Ni-Ti alloy, and the second wire is made of stainless steel.   The guide wire according to claim 1, wherein the welded portion coating layer has a plurality of convex portions.   The guide wire according to claim 12, wherein the convex portion has a hemispherical shape.

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