JP5296143B2 - Guide wire - Google Patents

Description

  The present invention relates to a guide wire, and particularly to a guide wire used when a catheter is introduced into a body cavity such as a blood vessel.

  The guide wire can be used for the treatment of a site where surgery is difficult, such as PTCA (Percutaneous Transluminal Coronary Angioplasty), or for the purpose of minimally invasive to the human body, Used to guide catheters used for examinations such as angiography. A guide wire used for PTCA surgery is inserted to the vicinity of the target vascular stenosis portion together with the balloon catheter with the tip of the guide wire protruding from the tip of the balloon catheter. Guide to near.

  The blood vessel is intricately curved, and the guide wire used to insert the balloon catheter into the blood vessel has flexibility and resilience to moderate bending, and pushability to transmit the operation at the proximal end to the distal side. In addition, torque transmission properties (collectively referred to as “operability”) and kink resistance (bending resistance) are required. Among these characteristics, as a structure for obtaining moderate flexibility, a structure having a metal coil having flexibility for bending around a thin tip core material of a guide wire, and for providing flexibility and resilience There is a guide wire using a super elastic wire such as Ni-Ti as a core material.

  In the conventional guide wire, the core material is substantially composed of one material, and a material having a relatively high elastic modulus is used in order to improve the operability of the guide wire. The flexibility is lost. Further, if a material having a relatively low elastic modulus is used in order to obtain the flexibility of the distal end portion of the guide wire, the operability on the proximal end side 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 heat treatment is performed on the distal end side and the proximal end side under different conditions to increase the flexibility of the distal end portion. A guide wire with increased rigidity has been proposed (see, for example, Patent Document 1). However, there is a limit to the control of flexibility by such heat treatment, and even if sufficient flexibility is obtained at the distal end portion, there is a case where satisfactory rigidity is not always obtained at the proximal end side.

JP-A-63-171570

  An object of the present invention is to provide a guide wire excellent in strength and operability by preventing or alleviating stress concentration on the connecting portion between the first wire on the distal end side and the second wire on the proximal end side.

Such an object is achieved by the present inventions (1) to (3) below.
(1) a linear first wire disposed on the distal end side and made of a metal material;
A linear second wire that is arranged on the base end side of the first wire and is made of a metal material having a larger elastic modulus than the constituent material of the first wire;
The first wire and the second wire are connected by welding,
In the welded portion between the first wire and the second wire, a protruding portion protruding in the outer peripheral direction is formed,
The protruding portion has a shape in which the proximal end side and the distal end side are asymmetrical with respect to the welding surface of the welded portion,
The guide wire, wherein the welding surface is located at a position deviated from a maximum outer diameter portion of the protruding portion.

(2) a linear first wire arranged on the tip side and made of a metal material;
A linear second wire that is arranged on the base end side of the first wire and is made of a metal material having a larger elastic modulus than the constituent material of the first wire;
The first wire and the second wire are connected by welding,
In the welded portion between the first wire and the second wire, a protruding portion protruding in the outer peripheral direction is formed,
The protruding portion has a shape in which the proximal end side and the distal end side are asymmetrical with respect to the welding surface of the welded portion,
The guide wire according to claim 1, wherein the welding surface is in a position biased toward a distal end side or a proximal end side in the protruding portion.

(3) The first wire is made of a Ni-Ti alloy,
The guide wire according to (1) or (2), wherein the second wire is made of stainless steel or a cobalt-based alloy.

  According to the present invention, it is possible to provide a guide wire with excellent operability by providing the first wire disposed on the distal end side and the second wire disposed on the proximal end side of the first wire. it can. In particular, by providing a first wire made of a metal material and a second wire made of a metal material made of a material having a higher elastic modulus than that of the first wire, the tip portion excellent in flexibility and rich in rigidity are provided. A guide wire having a proximal end portion and excellent in pushability, torque transmission performance and followability can be configured.

  In addition, since the first wire and the second wire are connected by welding and the protruding portion is formed in the welded portion, the coupling strength of the connecting portion (welded portion) is high, and the torsional torque from the second wire to the first wire And the pushing force can be transmitted reliably.

  Moreover, stress concentration on the welded portion can be prevented or alleviated by positioning the weld surface of the welded portion at a position deviated from the maximum outer diameter portion of the protruding portion. Therefore, when torsional torque or pushing force is applied from the second wire to the first wire, damage to the welded part due to stress concentration on the welded part can be prevented more reliably.

  As described above, the present invention achieves both prevention of breakage of the weld due to stress concentration on the weld and smooth movement.

It is a longitudinal cross-sectional view which shows the structural example of a guide wire. 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 schematic diagram for demonstrating the usage example of the guide wire shown in FIG. It is a schematic diagram for demonstrating the usage example of the guide wire shown in FIG. It is a longitudinal cross-sectional view which shows the other structural example of a guide wire. It is a longitudinal cross-sectional view which shows the other structural example of a guide wire. It is a longitudinal cross-sectional view which shows the other structural example of a guide wire. It is a longitudinal cross-sectional view which shows the other structural example of a guide wire. It is a longitudinal cross-sectional view which shows the other structural example of a guide wire. It is a longitudinal cross-sectional view which shows the example of the shape of the protrusion part in a guide wire. It is a longitudinal cross-sectional view which shows the example of the shape of the protrusion part in a guide wire. It is a longitudinal cross-sectional view which shows the example of the shape of the protrusion part in a guide wire. It is a longitudinal cross-sectional view which shows suitable embodiment of the guide wire of this invention. It is a longitudinal cross-sectional view which shows the other structural example of a guide wire.

  Hereinafter, the guide wire of the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

  FIG. 1 is a longitudinal sectional view showing a configuration example of a guide wire, and FIG. 2 is a diagram showing a procedure for connecting a first wire and a second wire in the guide wire shown in FIG. For convenience of explanation, the right side in FIG. 1 is referred to as “base end” and the left side is referred to as “tip”. 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 significantly different from the actual ratio (the same applies to FIGS. 5 to 14 described later).

  A guide wire 1A shown in FIG. 1 is a catheter guide wire used by being inserted into a catheter, and includes a first wire 2 disposed on the distal end side and a second wire disposed on the proximal end side of the first wire 2. It has a wire 3 and a spiral coil 4. The total length of the guide wire 1A is not particularly limited, but is preferably about 200 to 5000 mm. Further, the outer diameter of the guide wire 1A is not particularly limited, but it 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 illustrated configuration, the first wire 2 has an outer diameter gradually decreasing portion 16 whose outer diameter gradually decreases toward the distal end direction. As a result, the rigidity (bending rigidity, torsional rigidity) of the first wire 2 can be gradually reduced toward the distal direction, and as a result, the guide wire 1A obtains good flexibility at the distal end portion, and the blood vessel Follow-up performance and safety can be improved, and bending can also be prevented.

The length of the outer diameter gradually reducing unit 16 (the length indicated by _{L 1} in FIG. 1) is not particularly limited and is preferably about 10 to 1000 mm, more preferably about 20 to 300 mm. When L ₁ is in the above range, it is possible to the change in stiffness along the longitudinal direction more gradual (smoother).

  In the illustrated configuration, the outer diameter gradually decreasing portion 16 has a tapered shape in which the outer diameter continuously decreases at a substantially constant decrease rate in the distal direction. In other words, the taper angle of the outer diameter gradually decreasing portion 16 is substantially constant along the longitudinal direction. Thereby, in the guide wire 1A having the illustrated configuration, the change in rigidity along the longitudinal direction can be made more gradual (smooth). In addition, unlike such a configuration, the rate of decrease of the outer diameter toward the distal direction of the outer diameter gradually decreasing portion 16 (taper angle of the outer diameter gradually decreasing portion 16) may change along the longitudinal direction, For example, a portion where the reduction rate of the outer diameter is relatively large and a portion where the outer diameter is relatively small may be alternately formed a plurality of times. In this case, there may be a portion where the decrease rate of the outer diameter toward the distal end of the outer diameter gradually decreasing portion 16 becomes zero.

  The constituent material of the 1st wire 2 is not specifically limited, For example, stainless steel (For example, SUS304, SUS303, SUS316, SUS316L, SUS316J1, SUS316J1L, SUS405, SUS430, SUS434, SUS444, SUS429, SUS430F, SUS302 etc.), pseudo Various metal materials such as alloys exhibiting elasticity (including superelastic alloys) can be used, but superelastic alloys are preferred. Since the superelastic alloy is relatively flexible and has a resilience and is difficult to bend, the guide wire 1 </ b> A is sufficient for the tip side portion by configuring the first wire 2 with the superelastic alloy. Flexibility and resilience to bending can be obtained, follow-up to complicatedly curved and bent blood vessels can be improved, and more excellent operability can be obtained, and even if the first wire 2 repeatedly bends and bends, Since the 1 wire 2 is not bent due to the resilience, it is possible to prevent the operability from being deteriorated due to the bent wire being attached to the first wire 2 during use of the guide wire 1A.

  Pseudoelastic alloys include those in which the stress-strain curve by tension is any shape, including those in which transformation points such as As, Af, Ms, and Mf can be measured remarkably, and those that cannot be deformed. Anything that is distorted) and returns almost to its original shape upon removal of 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.

  The distal end portion of the second wire 3 is connected (connected) to the proximal end portion of the first wire 2. 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.

  The second wire 3 is usually made of a material having a different elastic modulus (Young's modulus (longitudinal elastic modulus), rigidity (lateral elastic modulus), and bulk elastic modulus) from the first wire 2. Thus, by joining and using wires having different elastic moduli, the guide wire 1A is excellent in operability.

  Further, the first wire and / or the second wire can be made of a so-called composite material, such as forming inner and outer layers of different materials. Even in such a case, it is preferable that the rigidity of the second wire is higher than that of the first wire.

  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, the cobalt-based alloy has a high elastic modulus when used as a wire and has an appropriate elastic limit. For this reason, the 2nd wire 3 comprised by the cobalt type alloy has the outstanding outstanding torque transmission, and it is hard to produce problems, such as buckling. Any cobalt-based alloy may be used as long as it contains Co as a constituent element, but it contains Co as a main component (Co-based alloy: Co content in the elements constituting the alloy) Is preferable, and a Co—Ni—Cr alloy is more preferably used. By using an alloy having such a composition as a constituent material of the second wire 3, the above-described effects become more remarkable. In addition, since an alloy having such a composition has plasticity even when deformed at room temperature, it can be easily deformed into a desired shape, for example, at the time of use. In addition, an alloy having such a composition has a high elastic modulus and can be cold-formed even as a high elastic limit, and by reducing the diameter while sufficiently preventing buckling from occurring due to the high elastic limit. And can have sufficient flexibility and rigidity to be inserted into a predetermined portion.

  Examples of the Co—Ni—Cr alloy include alloys having a composition of 28 to 50 wt% Co-10 to 30 wt% Ni-10 to 30 wt% Cr—remainder Fe, and a part of the other elements (substitution elements). Alloys substituted with are preferred. The inclusion of a substitution element exhibits a unique effect depending on the type. For example, the strength of the second wire 3 can be further improved by including at least one selected from Ti, Nb, Ta, Be, and Mo as the substitution element. In addition, when an element other than Co, Ni, and Cr is included, the content (of the entire substituted element) is preferably 30 wt% or less.

  Further, a part of Co, Ni, and Cr may be substituted with other elements. For example, a part of Ni may be substituted with Mn. Thereby, the further improvement of workability etc. can be aimed at, for example. Further, a part of Cr may be replaced with Mo and / or W. Thereby, the further improvement of an elastic limit, etc. can be aimed at. Among Co—Ni—Cr alloys, Co—Ni—Cr—Mo alloys containing Mo are particularly preferable.

  As a specific composition of the Co-Ni-Cr alloy, for example, <1> 40 wt% Co-22 wt% Ni-25 wt% Cr-2 wt% Mn-0.17 wt% C-0.03 wt% Be-balance Fe <2> 40 wt% Co-15 wt% Ni-20 wt% Cr-2 wt% Mn-7 wt% Mo-0.15 wt% C-0.03 wt% Be-balance Fe, <3> 42 wt% Co-13 wt% Ni- 20 wt% Cr-1.6 wt% Mn-2 wt% Mo-2.8 wt% W-0.2 wt% C-0.04 wt% Be-balance Fe, <4> 45 wt% Co-21 wt% Ni-18 wt% Cr- 1 wt% Mn-4 wt% Mo-1 wt% Ti-0.02 wt% C-0.3 wt% Be-balance Fe, <5> 34 wt% Co-21 wt% Ni-14 wt% Cr-0.5 wt% Mn-6w % Mo-2.5wt% Nb-0.5wt% Ta- balance being Fe, and the like. The Co—Ni—Cr alloy referred to in the present invention is a concept that includes these alloys.

  Moreover, when stainless steel is used as the constituent material of the second wire 3, the guide wire 1A can obtain better pushability and torque transmission.

  In the present invention, it is preferable that the first wire 2 and the second wire 3 are made of different kinds of alloys, and the first wire 2 is made of a material having a smaller elastic modulus than that of the constituent material of the second wire 3. It is preferred that As a result, the guide wire 1A 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 1A 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, the first wire 2 is made of a superelastic alloy, and the second wire 3 is made of a Co—Ni—Cr alloy or stainless steel. It is particularly preferable to do this. Thereby, the effect mentioned above becomes further remarkable.

  In the illustrated configuration, the second wire has a substantially constant outer diameter over substantially the entire length, but may have a portion where the outer diameter changes in the longitudinal direction.

  In addition, it is preferable to use a Ni—Ti-based alloy as the superelastic alloy constituting the first wire 2 in terms of flexibility and resilience on the tip side.

  The coil 4 is a member formed by spirally winding a wire (thin wire), and is installed so as to cover a portion on the distal end side of the first wire 2. In the configuration shown in the drawing, the portion on the distal end side of the first wire 2 is inserted through a substantially central portion inside the coil 4. Further, the distal end portion of the first wire 2 is inserted in a non-contact manner with the inner surface of the coil 4. In the configuration shown in the figure, the coil 4 has a slight gap between the spirally wound wires in a state where no external force is applied, but unlike the illustration, the coil 4 is spiraled in a state where no external force is applied. Wires wound in a shape may be densely arranged without a gap.

  The coil 4 is preferably made of a metal material. Examples of the metal material constituting the coil 4 include stainless steel, superelastic alloy, cobalt-based alloy, noble metals such as gold, platinum, and tungsten, or alloys containing these. In particular, when it is made of an X-ray opaque material such as a noble metal, X-ray contrast can be obtained in the guide wire 1A, and it can be inserted into the living body while confirming the position of the tip under X-ray fluoroscopy. It is possible and preferable. Moreover, you may comprise the coil 4 with the material from which the front end side and base end side differ. For example, the distal end side may be constituted by a coil made of an X-ray opaque material, and the proximal end side may be constituted by a coil made of a material (such as stainless steel) that relatively transmits X-rays. The total length of the coil 4 is not particularly limited, but is preferably about 5 to 500 mm.

  The proximal end portion and the distal end portion of the coil 4 are fixed to the first wire 2 by fixing materials 11 and 12, respectively. Further, an intermediate portion (position near the tip) of the coil 4 is fixed to the first wire 2 by a fixing material 13. The fixing materials 11, 12 and 13 are made of solder (brazing material). The fixing materials 11, 12 and 13 are not limited to solder, and may be adhesives. Moreover, the fixing method of the coil 4 is not limited to a fixing material, and for example, welding may be used. In order to prevent damage to the inner wall of the blood vessel, the distal end surface of the fixing material 12 is preferably rounded.

  In the illustrated configuration, since the coil 4 is installed, the first wire 2 is covered with the coil 4 and has a small contact area, so that the sliding resistance can be reduced. The operability of 1A is further improved.

  In the case of the illustrated configuration, the coil 4 has a circular cross section of the wire. However, the present invention is not limited to this, and the cross section of the wire is, for example, an ellipse or a quadrangle (particularly a rectangle). Also good.

  In such a guide wire 1A, the first wire 2 and the second wire 3 are connected (fixed) to each other by welding. As a result, the welded portion (connecting portion) 14 between the first wire 2 and the second wire 3 has a high bond strength (joining strength).

  In particular, in the configuration shown in the drawing, a protruding portion 15 protruding in the outer peripheral direction is formed on the welded portion 14. By forming such a protrusion 15, the bonding area between the first wire 2 and the second wire 3 is increased, and the bonding strength thereof is particularly high. As a result, the guide wire 1 </ b> A reliably transmits torsional torque and pushing force from the second wire 3 to the first wire 2.

  In addition, by forming the protruding portion 15, for example, the welded portion 14 between the first wire 2 and the second wire 3 can be easily visually recognized under X-ray fluoroscopy. As a result, by confirming the X-ray fluoroscopic image, it is possible to easily and reliably grasp the progress of the guide wire 1A and the catheter in the blood vessel and the like, which contributes to shortening of the operation time and improving safety. it can.

  In the configuration shown in the figure, the projecting portion 15 has a substantially arc-shaped contour on one side (upper side in FIG. 1) and the opposite side (lower side in FIG. 1) in the longitudinal section thereof. The welded portion 14 is located at the maximum outer diameter portion. Thereby, the area of the welding surface of the welding part 14 can be taken large, and there exists an advantage that higher bond strength (welding strength) is obtained. In addition, when the guide wire 1A is bent, the stress is dispersed in a portion having a small outer diameter near the protruding portion 15 and concentrated on the welded portion 14 because the welding surface of the welded portion 14 is present at the maximum outer diameter portion. There is nothing to do. In the present invention, it goes without saying that the shape of the protruding portion 15 and the position of the welded portion 14 with respect to the protruding portion 15 are not limited to this.

  Further, as described above, the first wire 2 and the second wire 3 are usually made of materials having different elastic moduli. For this reason, by providing the protrusion 15, the operator can easily and reliably recognize a site where the elastic modulus of the guide wire 1 </ b> A changes relatively greatly. As a result, the guide wire 1A is excellent in operability, and can contribute to shortening the treatment time and improving safety.

  Moreover, if such a protrusion part 15 is formed, a contact area with the inner wall of the catheter used with 1 A of guide wires can be made small. Thereby, the frictional resistance at the time of relatively moving the guide wire 1A and the catheter is reduced, and the slidability is improved. As a result, the operability of the guide wire 1A within the catheter is improved.

  Although the height of the protrusion part 15 is not specifically limited, It is preferable that it is 0.001-0.3 mm, and it is more preferable that it is 0.01-0.05 mm. If the height of the projecting portion 15 is less than the lower limit value, the above-described effects may not be sufficiently exhibited depending on the constituent materials of the first wire 2 and the second wire 3. On the other hand, when the height of the protruding portion 15 exceeds the upper limit, the inner diameter of the lumen to be inserted into the balloon catheter is determined, so that the outside of the second wire 3 on the proximal end side is compared with the height of the protruding portion 15. In some cases, the diameter of the second wire 3 must be reduced, and it may be difficult to fully exhibit the physical properties of the second wire 3.

  In the illustrated configuration, the connection end surface 21 of the first wire 2 to the second wire 3 and the connection end surface 31 of the second wire 3 to the first wire 2 are substantially perpendicular to the axial direction (longitudinal direction) of both wires. It is flat. Thereby, the process for forming the connection end surfaces 21 and 31 is very easy, and the above-described effects can be achieved without complicating the manufacturing process of the guide wire 1A.

  Note that, unlike the illustrated configuration, the connection end faces 21 and 31 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 14, 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 (attached) to a butt welder (not shown) are shown.

  In the procedure <2>, the first wire 2 and the second wire 3 are connected to the proximal end side connection end surface 21 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 31 on the side is brought into pressure contact. By this pressure contact, a molten layer (welded surface) is formed at the contact portion, and the first wire 2 and the second wire 3 are firmly connected. At this time, a protruding portion 15 protruding in the outer peripheral direction is formed on the welded portion 14. The size (height) of the protrusion 15 can be controlled by adjusting the applied voltage, the pressing pressure between the first wire 2 and the second wire 3, for example. Further, the size (height) of the protrusion 15 may be adjusted by polishing or the like.

  Next, in step <3>, the distal end side of the first wire 2 is polished to form the outer diameter gradually decreasing portion 16 in which the outer diameter gradually decreases in the distal direction.

  FIG. 3 and FIG. 4 are diagrams each showing a use state when the guide wire 1A is used for PTCA.

  3 and 4, 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 1A 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. 3, the distal end of the guide wire 1 </ b> A protrudes from the distal end of the guiding catheter 30 and is inserted into the right coronary artery 50 through the right coronary artery opening 60. Further, the guide wire 1A 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 part 70. Thereby, the passage of the balloon catheter 20 is secured. At this time, the welded portion 14 of the guide wire 1A is located near the base of the aortic arch 40 (in vivo).

  Next, as shown in FIG. 4, the distal end of the balloon catheter 20 inserted from the proximal end side of the guide wire 1A is projected from the distal end of the guiding catheter 30, and further advanced along the guide wire 1A 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.

  FIG. 5 is a longitudinal sectional view showing another configuration example of the guide wire. Hereinafter, other examples of the configuration of the guide wire according to the present invention will be described with reference to this figure. However, differences from the above-described guide wire will be mainly described, and description of similar matters will be omitted.

  In the illustrated guide wire 1B, the outer diameter gradually decreasing portion 16 is formed on the second wire 3, and the first wire 2 has a substantially constant outer diameter over substantially the entire length except for the protruding portion 15. ing. That is, in the guide wire 1 </ b> B, the outer diameter gradually decreasing portion 16 is provided on the proximal end side from the weld portion 14.

  Further, in the guide wire 1B having the illustrated configuration, the coil 4 is disposed so as to contact the protruding portion 15 on the proximal end side.

  FIG. 6 is a longitudinal sectional view showing still another configuration example of the guide wire. Hereinafter, a configuration example of the guide wire will be described with reference to this figure, but the description will focus on differences from the above-described guide wire, and description of similar matters will be omitted.

  In the guide wire 1 </ b> F having the illustrated configuration, the first wire 2 includes an outer diameter gradually decreasing portion 16 and an outer diameter gradually decreasing portion 18 provided on the proximal end side from the outer diameter gradually decreasing portion 16. As described above, the first wire 2 (second wire 3) may have outer diameter gradually decreasing portions at a plurality of portions.

  Further, in the guide wire 1F having the illustrated configuration, the second wire 3 has an outer diameter gradually decreasing portion 16 'near the tip thereof. That is, the second wire 3 includes a first part provided in the vicinity of the distal end portion thereof and a second part provided on the proximal side from the first part and having higher rigidity than the first part. Have. In the guide wire 1F, the outer diameter gradually decreasing portion 16 'constitutes a first portion. Thereby, the effect that the elastic transition of the 1st wire 2 and the 2nd wire 3 changes smoothly is acquired. Further, as the first portion, a constant outer diameter portion may be provided on the distal end side of the outer diameter gradually decreasing portion 16 ′, and the outer diameter gradually decreasing portion 16 ′ and the outer diameter constant portion may be combined to form the first portion. The constant outer diameter portion preferably has substantially the same rigidity as the first wire 2.

  Further, the guide wire 1F having the illustrated configuration has a coating layer 7 on the outer surface (outer peripheral surface) side thereof. Thus, the guide wire of the present invention may have a coating layer that covers all or part of its outer surface (outer peripheral surface). Such a covering layer 7 can be formed for various purposes. As an example, the operability of the guide wire 1F is reduced by reducing the friction (sliding friction) of the guide wire 1F and improving the slidability. May be improved.

  For this purpose, the coating layer 7 is preferably made of a material that can reduce friction. Thereby, the frictional resistance (sliding resistance) with the inner wall of the catheter used together with the guide wire 1F is reduced, the slidability is improved, and the operability of the guide wire 1F in the catheter becomes better. Further, since the sliding resistance of the guide wire 1F is reduced, when the guide wire 1F is moved and / or rotated in the catheter, the guide wire 1F is kinked (bent) or twisted, particularly in the vicinity of the welded portion. Can be prevented more reliably.

  Examples of materials that can reduce such friction include polyolefins such as polyethylene and polypropylene, polyvinyl chloride, polyesters (PET, PBT, etc.), polyamides, polyimides, polyurethanes, polystyrenes, polycarbonates, silicone resins, fluorine resins ( PTFE, ETFE, etc.), silicone rubber, other various elastomers (for example, polyamide elastomers, polyester elastomers, etc.) or composite materials thereof, among which fluorine resins (or including them) are particularly mentioned. Composite material) is preferred, and PTFE is more preferred.

  Other preferable examples of the material that can reduce friction include a hydrophilic material or a hydrophobic material. Of these, hydrophilic materials are particularly preferable.

  Examples of the hydrophilic material 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 materials (for example, polyacrylamide, block copolymer of polyglycidyl methacrylate-dimethylacrylamide (PGMA-DMAA)), water-soluble nylon, polyvinyl alcohol, polyvinylpyrrolidone and the like.

  In many cases, such a hydrophilic material exhibits lubricity by wetting (water absorption) and reduces frictional resistance (sliding resistance) with the inner wall of the catheter used together with the guide wire 1F. Thereby, the slidability of the guide wire 1F is improved, and the operability of the guide wire 1F in the catheter becomes better.

  The location where the coating layer 7 is formed may be the entire length of the guide wire 1F or a part in the longitudinal direction, but is preferably formed so as to cover the welded portion 14, that is, the location including the welded portion 14. .

  The covering layer 7 covers the outer diameter gradually decreasing portion 16 ′ and the protruding portion 15 and has a substantially uniform outer diameter. It should be noted that the “substantially uniform outer diameter” includes changes in the outer diameter that do not hinder use.

  The thickness of the coating layer 7 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 coating layer 7 is too thin, the purpose of forming the coating layer 7 may not be sufficiently exhibited, the peeling of the coating layer 7 may occur, and the thickness of the coating layer 7 is too thick. Then, the physical properties of the wire may be hindered, and the coating layer 7 may be peeled off.

  In the configuration shown in the figure, treatment (chemical treatment, heat treatment) for improving the adhesion of the coating layer 7 to the outer peripheral surface (surface) of the guide wire body (first wire 2, second wire 3, coil 4, etc.). Etc.) or an intermediate layer capable of improving the adhesion of the coating layer 7 can be provided.

  Moreover, the coating layer 7 may have a substantially constant composition in each part, or may have a different composition. For example, the constituent material of the coating layer 7 may be different between at least a region (first coating layer) covering the coil 4 and a region (second coating layer) closer to the base end than the region. Specifically, the first coating layer may be made of a hydrophilic material and the second coating layer may be made of a hydrophobic material. Further, as shown in the figure, the first coating layer and the second coating layer may be formed in a continuous manner in the longitudinal direction, but the base end of the first coating layer and the second coating layer The tip may be separated, or the first coating layer and the second coating layer may partially overlap.

  Such a coating layer (including a coating made of a hydrophilic material or a hydrophobic material) may be provided on, for example, a guide wire having the above-described configuration.

  As described above, the illustrated configuration example of the guide wire has been described. However, the present invention is not limited to this, and each part configuring the guide wire is replaced with an arbitrary configuration that can exhibit the same function. be able to. Moreover, arbitrary components may be added.

  For example, like the guide wires (guide wires 1C and 1D) shown in FIG. 7 and FIG. 8, other protrusions (protrusions other than the protrusions 15) 17 protruding in the outer peripheral direction are provided on parts other than the welded part 14. You may have. By forming such a protrusion 17, for example, the contact area with the inner wall of the catheter used with the guide wire can be further reduced. Thereby, the frictional resistance at the time of moving a guide wire and a catheter relatively is reduced, and slidability improves further. As a result, the operability of the guide wire in the catheter is particularly good.

  In the above-described configuration example, the configuration in which the joint portion of the two wires (the first wire 2 and the second wire 3) is provided at only one location has been described. However, the joint portion is formed at two or more locations. It may be. That is, the guide wire may have a wire other than the first wire and the second wire. For example, like the guide wire 1E shown in FIG. 9, you may have the 3rd wire 5 in the base end side of the 2nd wire 3. FIG. Thereby, characteristics such as elasticity can be set in more detail in each portion in the longitudinal direction of the guide wire, and the operability of the entire guide wire can be further improved.

  In this guide wire 1E, the second wire 3 and the third wire 5 are joined via a welded portion 14 similar to that described above, and the welded portion 14 preferably has the same protrusion as the protruding portion 15 described above. A portion 17 is formed.

  Moreover, in each structural example mentioned above, although the welding part 14 was demonstrated as what is located in the base end side rather than the base end of the coil 4, the welding part 14 is located in the front end side rather than the base end of the coil 4. FIG. You may do it.

  In the guide wires of the respective configuration examples described above, the protrusions 15 formed on the welded portion 14 may have various shapes. Hereinafter, an example of the shape of the protruding portion 15 (or 17) will be described with reference to FIGS.

  The protrusion 15 shown in FIG. 10 has a trapezoidal outline shape on one side (upper side in the figure) and the opposite side (lower side in the figure) in the longitudinal section. That is, in each structural example mentioned above, although the protrusion part 15 makes the substantially circular arc shape in which the outline shape of the one side in a longitudinal cross section and the other side curved each convexly, these shapes are, for example, A non-circular shape (non-arc shape) such as a trapezoid or a triangle may be used.

In the shape shown in FIG. 10, the vicinity of the welded portion 14 of the projecting portion 15, that is, the vicinity of the proximal end side and the vicinity of the distal end side of the welded portion 14 (the portion corresponding to the upper base of the trapezoid) has an outer diameter. Is almost constant. And the welding part 14 is located in the approximate center of the area | region where this outer diameter is substantially constant. The welded portion 14 is located at a portion of the protruding portion 15 having the largest outer diameter. By adopting such a configuration, stress concentration on the welded portion 14 can be prevented or alleviated, and when torsional torque or pushing force is applied from the second wire 3 to the first wire 2, the welded portion 14 is moved to. It is possible to more reliably prevent the weld 14 from being damaged due to the stress concentration.
In addition, instead of the above-described region having a substantially constant outer diameter, a gentle arc shape may be used.

  11 to 13 has an asymmetric shape between the proximal end side and the distal end side with respect to the welding surface (connection end surfaces 21, 31) of the welded portion 14 as a boundary.

  The protrusion 15 shown in FIG. 11 is substantially the same as that of each of the above embodiments in that the distal end side (the first wire 2 side) of the welded portion 14 has a profile shape on one side and the opposite side in the longitudinal section. An arc shape is formed, and on the base end side (second wire 3 side) from the welding surface of the welded portion 14, the contour shapes on one side and the opposite side thereof in the longitudinal section are gentle from the welded portion 14 toward the base end direction, respectively. It has a curved shape that is curved in a concave shape. Further, the welded portion 14 is located at a portion of the protruding portion 15 having the largest outer diameter.

  By adopting such a configuration, the transition of rigidity becomes gentle, and stress concentration on the proximal end side portion of the welded portion 14 can be prevented or alleviated, and the second wire 3 is twisted from the first wire 2. When torque or a pushing force is applied, damage or deformation of the portion due to stress concentration can be prevented more reliably.

  The protruding portion 15 shown in FIG. 12 is opposite to that in FIG. 11, and the base end side (second wire 3 side) from the welded surface of the welded portion 14 is the contour shape on one side and the opposite side in the longitudinal section. Are substantially arc-shaped in the same manner as in the above-described embodiments, and the distal end side (the first wire 2 side) of the weld surface of the weld portion 14 has a contour shape on one side and the opposite side in the longitudinal section thereof, respectively. A curved shape is formed that gently and concavely curves from 14 toward the tip. Further, the welded portion 14 is located at a portion of the protruding portion 15 having the largest outer diameter.

  By adopting such a configuration, it is possible to prevent or alleviate stress concentration on the distal end side portion of the welded portion 14, and when torsional torque or pushing force is applied from the second wire 3 to the first wire 2, Breakage, deformation, etc. of the part due to stress concentration can be prevented more reliably.

  Of course, as for the protrusion part 15, both the front end side and the base end side from the welding surface of the welding part 14 are toward the direction in which the outline shape of the one side in the longitudinal cross section and the other side is spaced apart from the welding part 14, respectively. It may have a curved shape that is gently and concavely curved.

Next, a preferred embodiment of the guide wire of the present invention will be described.
FIG. 13 is a longitudinal sectional view showing a preferred embodiment of the guide wire of the present invention. Hereinafter, a preferred embodiment of the guide wire will be described with reference to this figure, but the description will focus on the differences from the above-described guide wire, and the description of the same matters will be omitted.

  The overall shape of the protruding portion 15 shown in FIG. 13 is substantially the same as that of each of the structural examples described above, but in this protruding portion 15, the welded surface of the welded portion 14 is the base end side (second wire 3 The position is biased to the side. On the contrary, in the projecting portion 15, the welding surface of the welded portion 14 may be in a position that is biased toward the distal end side (first wire 2 side).

  By adopting such a configuration, the welding surface of the welded portion 14 does not become the central portion in the axial direction of the protruding portion 15, that is, the position where the welded surface of the welded portion 14 deviates from the maximum outer diameter portion of the protruding portion 15. Therefore, the stress concentration on the welded portion 14 can be prevented or alleviated. Therefore, when a torsional torque or a pushing force is applied from the second wire 3 to the first wire 2, the stress concentration on the welded portion 14 is caused. Damage to the welded portion 14 can be more reliably prevented.

  In addition, the structure in which the welding surface of the welding part 14 as mentioned above is in the position biased to the proximal end side or the distal end side in the projecting part 15 is, for example, one side in the longitudinal section of the projecting part 15 as shown in FIG. It can also be applied to the case where the contour shape on the opposite side is non-circular (non-arc-shaped).

  As described above, the protrusion 15 has a shape in which the proximal end side and the distal end side are asymmetrical with respect to the weld surface of the welded portion 14, thereby preventing or reducing stress concentration on the welded portion 14. When the torsional torque or the pushing force is applied from the second wire 3 to the first wire 2, the excellent effect that the welded portion 14 can be more reliably prevented from being damaged due to the stress concentration on the welded portion 14. Is done.

Next, another configuration example of the guide wire will be described.
FIG. 14 is a diagram illustrating another configuration example of the guide wire. Hereinafter, other examples of the configuration of the guide wire will be described with reference to this figure, but the description will focus on the differences from the above-described guide wire, and description of similar matters will be omitted.

  As shown in FIG. 14, the vicinity of the connecting portion (welded portion 14) between the first wire 2 and the second wire 3 is made thinner than the other portions, and welding is performed in the longitudinal direction of the small diameter portion 19. A portion 14 and a protruding portion 15 are formed. Further, as shown in FIG. 14, the small diameter portion 19 is formed on the first wire thin diameter portion 191 formed on the proximal end side of the first wire 2 and on the distal end side of the second wire 3. And a second wire narrow diameter portion 192.

  By adopting such a configuration, stress concentration on the welded portion 14 can be prevented or alleviated, and when torsional torque or pushing force is applied from the second wire 3 to the first wire 2, the welded portion 14 is moved to. It is possible to more reliably prevent the weld 14 from being damaged due to the stress concentration.

  Here, the maximum outer diameter of the protruding portion 15 is substantially equal to or less than the outer diameter of each portion on the distal end side from the first wire thin diameter portion 191 and the proximal end side from the second wire thin diameter portion 192. Preferably there is. Thereby, the guide wire can be moved more smoothly with respect to the catheter.

  As shown in FIG. 14, the first wire narrow diameter portion 191 is provided on the distal end side, and is provided on the proximal end side with an outer diameter gradually increasing portion 191a whose outer diameter gradually increases in the distal end direction. The outer diameter gradually decreasing portion 191b whose outer diameter gradually decreases in the distal direction, and the outer diameter constant portion provided between the outer diameter gradually increasing portion 191a and the outer diameter gradually decreasing portion 191b, the outer diameters being substantially equal along the longitudinal direction. 191c.

  Similarly, the second wire narrow diameter portion 192 is provided on the distal end side, and is provided on the proximal end side with an outer diameter gradually increasing portion 192a in which the outer diameter gradually increases in the distal end direction, and the outer diameter increases in the distal end direction. The outer diameter gradually decreasing portion 192b gradually decreases, and is provided between the outer diameter gradually increasing portion 192a and the outer diameter gradually decreasing portion 192b. The outer diameter constant portion 192c has a substantially constant outer diameter along the longitudinal direction.

  The first wire small diameter portion 191 and the second wire small diameter portion 192 are formed symmetrically with respect to the welded portion 14 (that is, the weld surface).

  In the configuration shown in FIG. 14, the shape of the protruding portion 15 is substantially the same as that shown in FIG. 10, but is not limited to this, and for example, the shape shown in FIG. 1 or any one of FIGS. Also good.

  Further, the configuration shown in FIGS. 11 to 14 as described above may be applied to any of the configuration examples described above. In particular, in the configuration example shown in FIG. 6, the configuration shown in FIGS. 11 to 14 can be applied to the protrusion 17.

1A to 1F Guide wire 2 First wire 21 Connection end surface 3 Second wire 31 Connection end surface 4 Coil 5 Third wire 7 Covering layer 11, 12, 13 Fixing material 14 Welding portion 15 Protruding portion 16, 16 'Outer diameter gradually decreasing portion 17 Protruding portion 18 Outer diameter gradually decreasing portion 19 Thin diameter portion 191 First wire thin diameter portion 192 Second wire thin diameter portion 191a, 192a Outer diameter gradually increasing portion 191b, 192b Outer diameter gradually decreasing portion 191c, 192c Constant outer diameter portion 20 Balloon catheter 201 Balloon 30 Guiding catheter 40 Aortic arch 50 Right coronary artery 60 Right coronary artery opening 70 Blood vessel stenosis

Claims (3)

A linear first wire disposed on the distal end side and made of a metal material;
A linear second wire that is arranged on the base end side of the first wire and is made of a metal material having a larger elastic modulus than the constituent material of the first wire;
The first wire and the second wire are connected by welding,
In the welded portion between the first wire and the second wire, a protruding portion protruding in the outer peripheral direction is formed,
The protruding portion has a shape in which the proximal end side and the distal end side are asymmetrical with respect to the welding surface of the welded portion,
The guide wire, wherein the welding surface is located at a position deviated from a maximum outer diameter portion of the protruding portion. A linear first wire disposed on the distal end side and made of a metal material;
A linear second wire that is arranged on the base end side of the first wire and is made of a metal material having a larger elastic modulus than the constituent material of the first wire;
The first wire and the second wire are connected by welding,
In the welded portion between the first wire and the second wire, a protruding portion protruding in the outer peripheral direction is formed,
The protruding portion has a shape in which the proximal end side and the distal end side are asymmetrical with respect to the welding surface of the welded portion,
The guide wire according to claim 1, wherein the welding surface is in a position biased toward a distal end side or a proximal end side in the protruding portion. The first wire is made of a Ni-Ti alloy,
The guide wire according to claim 1 or 2, wherein the second wire is made of stainless steel or a cobalt-based alloy.

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