JP4405252B2 - Medical wire - Google Patents

Description

  The present invention relates to a medical wire, and more particularly to a balloon fixing wire used for dilating a stenosis of a blood vessel.

  Conventionally, a less invasive treatment such as PTCA (Percutaneous Transluminal Coronary Angioplasty) has been performed for dilatation treatment of a coronary artery stenosis as compared with surgical operation. In this PTCA operation, first, a guide wire for guiding a balloon catheter is passed through a stenosis (hereinafter simply referred to as “stenosis”) of a blood vessel (such as a coronary artery), the balloon catheter is advanced along the guide wire, and the balloon Is positioned at the stenosis, and the balloon is expanded to push the stenosis.

  As such a guide wire, it has been proposed to provide a hydrophilic lubricating layer that exhibits lubricity by wetting on the outer surface of the guide wire in order to make the progression in the blood vessel smoother and easier. (For example, refer to Patent Document 1). According to this guide wire, there is an advantage that the narrowed portion can be easily and safely passed.

  By the way, when the balloon is expanded in the stenosis part, the balloon may slip from the stenosis part and come out of the stenosis part, or the whole stenosis part may not be uniformly spread. In view of this, it is conceivable to prepare another wire in addition to the guide wire for guiding the balloon catheter, and sandwich this wire between the balloon and the narrowed portion to prevent the balloon from slipping.

  However, when the guide wire having the hydrophilic lubrication layer described above is used as it is as the wire for fixing the balloon, it is excellent in the passage through the constricted portion, but the frictional force with the outer surface of the balloon due to the lubricity of the surface. There is a problem that the balloon is not sufficiently fixed (prevents slipping) when the balloon is expanded.

JP-A-10-146390

  An object of the present invention is to provide a medical wire that can easily and reliably prevent balloon sliding when the balloon of the balloon catheter is expanded.

Such an object is achieved by the present inventions (1) to (3) below. Further, the following (4) and (8) are preferable.
(1) a wire body having a linear first wire portion disposed on the distal end side and a linear second wire portion disposed on the proximal end side of the first wire portion;
A coating layer covering at least the outer periphery of the first wire portion;
A medical wire having a slipping layer formed on the outer surface of the covering layer,
The slipping layer has a deficient part in which a part of the slipping layer is lost in the middle of the longitudinal direction,
The medical wire according to claim 1, wherein the defect portion is in contact with an outer surface of a balloon of a balloon catheter inserted into a blood vessel .

(2) a wire body having a linear first wire portion disposed on the distal end side and a linear second wire portion disposed on the proximal end side of the first wire portion;
A coating layer covering at least the outer periphery of the first wire portion;
A medical wire having a slipping layer formed on the outer surface of the covering layer,
The slippery layer has a deactivation part in the middle of its longitudinal direction, the slippery function being inferior to other parts of the slippery layer,
The medical wire according to claim 1, wherein the inactive portion is in contact with an outer surface of a balloon of a balloon catheter inserted into a blood vessel .

(3) a wire body having a linear first wire portion disposed on the distal end side and a linear second wire portion disposed on the proximal end side of the first wire portion;
A medical wire having a coating layer covering at least the outer periphery of the first wire portion,
The covering layer has a sliding resistance increasing portion in the middle of its longitudinal direction, in which the sliding resistance of the balloon catheter with respect to the balloon is larger than other portions of the covering layer,
The medical wire, wherein the sliding resistance increasing portion is in contact with an outer surface of a balloon of the balloon catheter inserted in a blood vessel .

( 4 ) The medical wire according to any one of (1) to ( 3 ), wherein at least the distal end portion has X-ray contrast properties.

( 5 ) The medical wire according to (1) above, which has a contrast marker capable of grasping a position of the defect portion.

( 6 ) The medical wire according to (2), wherein the medical wire has a contrast marker capable of grasping a position of the inactivated part.

( 7 ) The medical wire according to (3), wherein the medical wire has a contrast marker capable of grasping a position of the sliding resistance increasing portion.

( 8 ) The medical wire according to any one of (1) to ( 7 ), wherein the second wire portion is made of a material having a larger elastic modulus than a constituent material of the first wire portion.

The coating layer is preferably composed of a thermoplastic elastomer, a silicone resin or a fluorine resin.
The average thickness of the coating layer is preferably 1 to 20 μm.

  It is preferable that the wire body has an outer diameter gradually decreasing portion whose outer diameter gradually decreases in the distal direction.

  It is preferable to have a spiral coil that covers at least the distal end portion of the first wire portion.

The first wire portion is preferably made of a superelastic alloy.
The second wire part is preferably made of stainless steel or a Co-based alloy.

  The Co-based alloy is preferably a Co—Ni—Cr alloy.

  By using the medical wire of the present invention, the balloon can be easily and reliably prevented from slipping when the balloon of the balloon catheter inserted into the blood vessel is expanded. Thereby, a lesioned part (stenosis part) can be reliably expanded with a balloon.

  In addition, by providing X-ray contrast properties, it is possible to easily grasp the parts (defects, inactivated parts, sliding resistance increasing parts) in contact with the balloon of the medical wire from outside the body under X-ray fluoroscopy. The position of the part can be easily and accurately aligned.

  Hereinafter, the medical wire of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

  FIG. 1 is a longitudinal sectional view showing a first embodiment of the medical wire of the present invention. 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”. Further, in FIG. 1, for the sake of easy understanding, the length direction of the medical wire is shortened and the thickness direction of the medical wire is exaggerated and schematically illustrated, and the ratio of the length direction to the thickness direction is illustrated. Is different from the actual (the same applies to FIGS. 2 to 4 described later).

  A medical wire 1 shown in FIG. 1 is used by being inserted into a blood vessel together with a balloon catheter, and is a balloon fixing wire for fixing a balloon of the balloon catheter to a stenosis (lesion) of a blood vessel, It has a wire body 10 formed by connecting a first wire portion 2 disposed on the distal end side and a second wire portion 3 disposed on the proximal end side of the first wire portion 2. The wire body 10 constitutes a core wire of the medical wire 1.

  Although the full length of the medical wire 1 is not specifically limited, About 150-7000 mm is preferable and it is more preferable that it is about 200-5000 mm.

  The 1st wire part 2 is comprised with the wire which has flexibility, especially elasticity. Although the length of the 1st wire part 2 is not specifically limited, It is preferable that it is about 20-1000 mm.

  In the present embodiment, the first wire portion 2 has at least one outer diameter gradually decreasing portion 25 whose outer diameter gradually decreases from the proximal end toward the distal end in at least a part of the longitudinal direction. . By having such an outer diameter gradually decreasing part 25, the rigidity (bending rigidity, torsional rigidity) of the first wire part 2 can be gradually decreased toward the distal end direction. Good flexibility can be obtained at the distal end portion, the followability to blood vessels and safety can be improved, and bending and the like can also be prevented.

  In the illustrated configuration, the outer diameter gradually decreasing portion 25 is formed on a part of the first wire portion 2, but the entire first wire portion 2 may constitute the outer diameter gradually decreasing portion. Further, the taper angle (decrease rate of the outer diameter) of each outer diameter gradually decreasing portion 25 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.

  Moreover, the 1st wire part 2 may have a part with a constant outer diameter along the longitudinal direction in the front end side or base end side of the outer diameter gradually decreasing part 25. That is, as shown in the drawing, the first wire portion 2 has a plurality of outer diameter gradually decreasing portions 25 whose outer diameter gradually decreases toward the distal end direction, and the outer diameter extends in the longitudinal direction between them (or front and rear). In other words, a certain part may be formed. Even in such a case, the same effect as described above can be obtained.

  In addition, although not shown in figure, such an outer diameter gradually decreasing part 25 may be formed in the 2nd wire part 3 mentioned later.

  The constituent material of the 1st wire part 2 is not specifically limited, For example, various metal materials, such as stainless steel, can be used, Especially, the alloy (a superelastic alloy is included) which shows pseudoelasticity among them is especially used. preferable. More preferably, it is a superelastic alloy. Since the superelastic alloy is relatively flexible, has a resilience, and is difficult to bend, the medical wire 1 can be obtained by forming the first wire portion 2 with a superelastic alloy. Sufficient flexibility and resilience to bending, improved followability to complicatedly curved and bent blood vessels, improved operability, and the first wire portion 2 repeatedly bent and bent However, since the first wire portion 2 is not bent due to the resilience, it is possible to prevent the operability from being deteriorated due to the first wire portion 2 being bent during the use of the medical 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. Thereby, the front-end | tip part of the medical wire 1 becomes a thing especially excellent in a softness | flexibility and a recoverability. In addition, the superelastic alloy represented by the Ni-Ti type alloy is excellent also in the adhesiveness of the coating layer 5 mentioned later.

  The distal end of the second wire portion 3 is preferably connected (connected) to the proximal end of the first wire portion 2 by welding. The 2nd wire part 3 is comprised with the wire which has flexibility, especially elasticity.

  Although the length of the 2nd wire part 3 is not specifically limited, It is preferable that it is about 20-4800 mm. Further, the outer diameter of the second wire portion 3 (the outer diameter of the portion where the outer diameter is constant) is not particularly limited, but it is usually preferably about 0.15 to 1.4 mm, and 0.2 to 1 More preferably, it is about 0.2 mm.

  The second wire portion 3 may be made of a material having the same physical characteristics (for example, elastic modulus) as the first wire portion 2, but the elastic modulus (Young's modulus (longitudinal) (Elastic modulus), rigidity (transverse elastic modulus), and bulk modulus) are preferably made of a material having a large value. Thereby, moderate rigidity (bending rigidity, torsional rigidity) is obtained for the second wire portion 3, the medical wire 1 becomes so-called firm and the pushability and torque transmission performance are improved, and more excellent insertion is achieved. Operability is obtained.

  The constituent material (material) of the second wire portion 3 is not particularly limited, and for example, stainless steel (for example, SUS304, SUS303, SUS316, SUS316L, SUS316J1, SUS316J1L, SUS405, SUS430, SUS434, SUS444, SUS429, SUS430F, SUS302). All kinds of SUS, etc.), various metal materials such as piano wire, cobalt alloy, and pseudoelastic alloy can be used.

  Among these, the cobalt-based alloy has a high elastic modulus when used as a wire (thin wire) and has an appropriate elastic limit. For this reason, the 2nd wire part 3 comprised by the cobalt type alloy has the outstanding outstanding torque transmission, and it is hard to produce problems, such as buckling, very much. 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 portion 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, by including at least one selected from Ti, Nb, Ta, Be, and Mo as a substitution element, the strength of the second wire portion 3 can be further improved. 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.

  In addition, when stainless steel is used as the constituent material of the second wire portion 3, the medical wire 1 can obtain better pushability and torque transmission.

  Moreover, in this invention, it is preferable to comprise the 1st wire part 2 and the 2nd wire part 3 with a dissimilar metal, and the 1st wire part 2 has a smaller elastic modulus than the constituent material of the 2nd wire part 3. It is preferably made of a material. Thereby, the medical wire 1 has excellent flexibility at the distal end portion and rich rigidity (bending rigidity, torsional rigidity) at the proximal end portion. As a result, the medical 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, safety Improves.

  Further, as a specific combination of the first wire portion 2 and the second wire portion 3, the first wire portion 2 is made of a superelastic alloy, and the second wire portion 3 is made of a Co—Ni—Cr alloy or It is particularly preferable to use stainless steel. Thereby, the effect mentioned above becomes further remarkable.

  In the configuration shown in the figure, the second wire portion 3 has a substantially constant outer diameter over almost the entire length. However, a portion where the outer diameter changes in the longitudinal direction, for example, the outer diameter gradually decreasing portion as described above. You may have.

  The first wire portion 2 and the second wire portion 3 are preferably welded. As a result, the bonding portion (bonding surface) 14 between the first wire portion 2 and the second wire portion 3 has a high bonding strength (bonding strength). Therefore, the medical wire 1 is separated from the second wire portion 3. Torsional torque and pushing force are reliably transmitted to the first wire portion 2.

Moreover, it is preferable that the outer peripheral part of the junction part 14 is substantially smooth.
In the present embodiment, the joint surface of the joint portion 14 is a plane that is substantially perpendicular to the axial direction (longitudinal direction) of the wire body 10. Thereby, the process for forming the joint surface of the 1st wire part 2 and the 2nd wire part 3 is very easy, and the said effect can be achieved, without complicating the manufacturing process of the medical wire 1. FIG. it can.

  Note that, unlike the illustrated configuration, the joint surface between the first wire portion 2 and the second wire portion 3 may be inclined with respect to a plane perpendicular to the axial direction (longitudinal direction) of both wires, and may be a concave surface. Or it may be convex.

  The method for welding the first wire portion 2 and the second wire portion 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, the joint part 14 can obtain higher bond strength.

  Such a medical wire 1 has an X-ray contrast property at least at its distal end. That is, in the present embodiment, the contrast marker 4 having a coil shape is provided at the distal end portion of the first wire portion 2. The contrast marker 4 is composed of a linear body wound spirally.

  As a constituent material of the contrast marker 4, various materials having X-ray contrast properties (X-ray opaque material) are used. Examples of such a material include noble metals such as gold, platinum, and tungsten, or alloys containing them (for example, platinum-iridium alloys).

  The contrast marker 4 is provided at a position that generally indicates a position of a defect portion 71 of the slipping layer 7 described later. That is, as shown in FIG. 1, the contrast marker 4 is placed at a position where the base end thereof substantially coincides with the tip of the defect portion 71.

  The outer periphery of the first wire portion 2 is covered with a covering layer 5. In this case, the contrast marker 4 is also covered with the coating layer 5. The covering layer 5 can be formed for various purposes, and an example thereof is a layer for the purpose of improving safety when the medical wire 1 is inserted into a blood vessel. For this purpose, the covering layer 5 is preferably made of a material (soft material) rich in flexibility.

  Examples of such flexible materials include polyolefins such as polyethylene and polypropylene, polyvinyl chloride, polyester (PET, PBT, etc.), polyamide, polyimide, polyurethane, polystyrene, silicone resin, polyurethane elastomer, polyester elastomer, polyamide Examples thereof include thermoplastic resins such as elastomers, various rubber materials such as latex rubber and silicone rubber, or composite materials in which two or more of these are combined.

  In particular, when the coating layer 5 is made of a thermoplastic resin such as polyurethane elastomer or various rubber materials, the flexibility of the distal end portion of the medical wire 1 is further improved. It is possible to more reliably prevent damage to the inner wall of the blood vessel, and the safety is extremely high.

  Another purpose of forming the coating layer 5 is to enable more reliable fixation (prevention of slipping) of a balloon, which will be described later. As will be described later, the slippery layer 7 formed on the covering layer 5 has a defect portion 71, and the covering layer 5 is exposed on the surface of the defect portion 71. Since the defect portion 71 is a portion where the surface of the balloon comes into contact, the balloon can be more reliably fixed by using a material having a large frictional resistance with the balloon as the covering layer 5.

  Examples of the constituent material of the coating layer 5 that is advantageous for fixing the balloon include thermoplastic elastomers such as polyurethane elastomer, polyester elastomer, and polyamide elastomer, and various rubber materials such as latex rubber and silicone rubber.

  In the constituent material of the coating layer 5, powder of a material having contrast properties, filler, or the like may be added. Thereby, X-ray contrast property can be obtained at least at the tip of the medical wire 1. Examples of the contrast-enhancing material constituting such powders and fillers include noble metals such as gold, platinum, and tungsten, or alloys containing them (for example, platinum-iridium alloys), other various metals, barium carbonate, barium sulfate, and the like. Is mentioned.

  Moreover, in this embodiment, the coating layer 6 similar to the coating layer 5 is provided in the outer periphery of all or one part of the 2nd wire part 3 (refer FIG. 1).

  The covering layer 6 can be provided for the purpose of improving the slidability of the medical wire 1. For this purpose, the covering layer 6 is preferably made of a material capable of reducing friction. Thereby, the frictional resistance (sliding resistance) with the inner wall of the catheter (not shown) for inserting the medical wire 1 and guiding it to the target site is reduced, and the slidability is improved. The operability of the wire 1 becomes better. In addition, since the sliding resistance of the medical wire 1 is lowered, when the medical wire 1 is moved and / or rotated in the catheter, the medical wire 1 is kinked or twisted, particularly in the vicinity of the joint 14. It is possible to more reliably prevent kinks and twists.

  Examples of the material capable of reducing such friction include polycarbonate, polyester (PET, PBT, etc.), fluorine-based resin (PTFE, ETFE, etc.), silicone resin, and polyolefin (PP, PE, etc.).

  The locations where the coating layers 5 and 6 are formed may be the entire length of the wire body 10 or a part in the longitudinal direction. In particular, it is preferable that the coating layer 5 covers at least the first wire portion 2 to the middle or the base end of the first wire portion 2. Moreover, the coating layer 5 and the coating layer 6 may partially overlap.

  The thicknesses of the coating layers 5 and 6 are not particularly limited, but usually, the thickness (average) is preferably about 2 to 400 μm, more preferably about 5 to 300 μm. If the thickness of the coating layers 5 and 6 is too thin, the purpose of forming them may not be sufficiently exhibited, the layers may be peeled off, and the thickness of the coating layers 5 and 6 is too thick. And, the physical properties (rigidity, flexibility, elasticity, etc.) of the wire may be hindered, and the layer may be peeled off.

  In the present invention, the outer peripheral surface (surface) of the wire main body 10 (particularly the first wire portion 2) is subjected to treatment (chemical treatment, heat treatment, etc.) for improving the adhesion of the coating layers 5 and 6, An intermediate layer that can improve the adhesion of the coating layers 5 and 6 can also be provided.

On the outer surface of the covering layer 5, a slipping layer (lubricating layer) 7 that generates slipping is provided.
Examples of the slipping layer 7 include those made of a hydrophilic material or a hydrophobic material. 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, polyglycidyl methacrylate-dimethylacrylamide (PGMA-DMAA) block copolymer), water-soluble nylon, polyvinyl alcohol, polyvinylpyrrolidone, and the like.

  Such hydrophilic materials often exhibit lubricity (lubricity) by wetting (water absorption) and reduce friction resistance (sliding resistance) with the inner wall of the catheter that guides the medical wire 1. Can do. Further, the frictional resistance with the inner surface of the blood vessel can be reduced. Thereby, the slidability of the medical wire 1 is improved, and the operability of the medical wire 1 becomes better.

  On the other hand, examples of the hydrophobic material that can form the slipping layer 7 include fluorine resins such as polytetrafluoroethylene (PTFE) and silicone.

  Although the thickness of the slippery layer 7 is not specifically limited, About 2-100 micrometers is preferable and about 5-50 micrometers is more preferable. If the thickness of the slippery layer 7 is too thick, there is a risk that the flexibility of the wire may be impaired depending on its constituent materials, etc. (or the physical properties of the wire may be impaired). Alternatively, the slipping layer 7 may be peeled off.

  The slippery layer 7 has a defect portion 71 in which a part of the slippery layer 7 is missing in the middle of the longitudinal direction. In the defect portion 71, the lower coating layer 5 is exposed. As shown in FIG. 5, the medical wire 1 is used such that the defect portion 71 contacts (contacts) the outer surface of the balloon 21 of the balloon catheter 20 inserted into the blood vessel. At this time, since the outer surface of the balloon 21 is in contact with the surface of the coating layer 5 exposed in the defect portion 71, the balloon 21 is prevented from slipping (mainly moving in the axial direction), and the balloon 21 is securely fixed. The

  For this reason, the covering layer 5 has a sliding resistance increasing portion in the middle of its longitudinal direction that has a sliding resistance larger than the other part of the covering layer 5 (the part where the slipping layer 7 is present). In other words, the missing portion 71 corresponds to this sliding resistance increasing portion.

The length _{L 1} of the defect 71 is not particularly limited, well being and enough to sufficiently cover the length of the balloon 21, specifically, _{L 1} is about 10~50mm preferably, 15 About ~ 45 mm is more preferable.

The length _{L 2} to the tip of the defect portion 71 from the distal end of the medical wire 1 is preferably about 5 to 50 mm, about 10~40mm is more preferable.

Examples of a method for forming such a defect portion 71 include the following method.
First, when the slippery layer 7 is formed on the coating layer 5, masking is performed on a portion that should become the defective portion 71, and after the slippery layer 7 is formed by, for example, a coating method, the mask is removed. A defect portion 71 is formed at a portion where the mask is removed.

  Secondly, after the slipping layer 7 is formed on the entire surface of the covering layer 5, the slipping layer at that portion is removed from the portion where the defect portion 71 is to be formed using, for example, a solvent. Thereby, the defect | deletion part 71 is formed.

  FIG. 2 is a longitudinal sectional view showing a second embodiment of the medical wire of the present invention. Hereinafter, the second embodiment will be described with a focus on differences from the first embodiment described above, and description of similar matters will be omitted.

  In the medical wire 1 of the second embodiment, a slipping layer 7 is provided with a deactivated portion 72 whose slipping function is inferior to other portions of the slipping layer 7 in place of the defect portion 71. Other configurations are the same as those in the first embodiment.

  In the inactive portion 72, the frictional resistance (sliding resistance) of the balloon catheter 20 with respect to the outer surface of the balloon 21 is larger than that in other portions of the slipping layer 7. Therefore, the balloon 21 that has come into contact with the deactivated portion 72 is prevented from sliding (mainly moving in the axial direction), and the balloon 21 is securely fixed.

  For this reason, the coating layer 5 has an increase in sliding resistance in the middle of its longitudinal direction, where the sliding resistance is greater than that of other parts of the coating layer 5 (parts other than the deactivation portion 72 of the slipping layer 7). The deactivation part 72 corresponds to this sliding resistance increasing part.

The length L ₁ and L ₂ of the deactivation unit 72 is the same as the first embodiment.
As a method for forming such a deactivation portion 72, for example, after forming the hydrophilic slipping layer 7 on the entire coating layer 5, the deactivation portion 72 is formed on the portion where the deactivation portion 72 is to be formed. By using a method of treating with (acetone, THF, etc.) or a method of irradiating with ultraviolet rays, the lubricity of the part is lost (reduced). Thereby, the deactivation part 72 is formed.

  FIG. 3 is a longitudinal sectional view showing a third embodiment of the medical wire of the present invention. Hereinafter, the third embodiment will be described with a focus on differences from the first embodiment described above, and description of similar matters will be omitted.

  The medical wire 1 according to the third embodiment is different from the first embodiment in the structure of the distal end portion. The medical wire 1 includes a first coil 8 and a second coil 9 that are installed so as to cover at least the distal end portion of the first wire portion 2. The first coil 8 and the second coil 9 are members formed by spirally winding a wire (thin wire), and are arranged in the order of the first coil 8 and the second coil 9 from the base end side.

  In the configuration shown in the drawing, the portion on the distal end side of the first wire portion 2 is inserted through a substantially central portion inside the first coil 8 and the second coil 9. Further, the distal end portion of the first wire portion 2 is inserted in a non-contact manner with the inner surfaces of the coils 8 and 9. The joint portion 14 is located on the base end side from the base end of the first coil 8.

  In the configuration shown in the figure, the first coil 8 and the second coil 9 have a slight gap between the spirally wound wires in a state where no external force is applied. The wire wound spirally may be densely arranged without a gap in a state where no is applied.

  Each of the first coil 8 and the second coil 9 is preferably made of a metal material. In this case, the second coil 9 is made of a material (X-ray opaque material) having an X-ray contrast property such as a noble metal such as gold, platinum, tungsten, or an alloy containing these metals (for example, a platinum-iridium alloy). Preferably, the first coil 8 is made of a material having a lower X-ray contrast than the second coil 9, in particular, a material having little X-ray contrast, such as stainless steel. Is preferred.

  Although the sum of the length of the 1st coil 8 and the 2nd coil 9 is not specifically limited, It is preferable that it is about 10-500 mm, and it is more preferable that it is about 50-450 mm.

  The proximal end portion of the first coil 8, the distal end portion of the first coil, the proximal end portion of the second coil, and the distal end portion of the second coil are fixed to the first wire portion 2 by fixing materials 11 and 12, respectively. .

  The fixing materials 11, 12 and 13 are made of, for example, 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 1st coil 8 and the 2nd coil 9 is not restricted to a fixing material, For example, welding may be sufficient. In order to prevent damage to the inner wall of the blood vessel, the distal end surface of the fixing material 13 located at the distal end is preferably rounded.

  By providing the first coil 8 and the second coil 9 as described above, the flexibility or elasticity of the first wire portion 2 can be improved.

  In the case of the present embodiment, the first coil 8 and the second coil 9 have a circular cross section of the wire, but the cross section of the wire is not limited to this. ) Etc.

  A covering layer 16 is formed so as to cover the outer circumferences of the first coil 8 and the second coil 9. As this coating layer 16, the thing similar to the coating layer 5 mentioned above can be used. In the present invention, the slipping layer 7 may be provided directly on the outer surfaces of the first coil 8 and the second coil 9 without providing such a coating layer 16.

On the outer surface of the covering layer 16, the slipping layer 7 similar to the above is provided. This slipping layer 7 has the same defective portion 71 as described above. The length L ₁ and L ₂ of the defective portion _{71, with} respect to such method of forming the defect 71 is the same as the first embodiment.

  A ring-shaped contrast marker 15 is provided at a position near the base end of the defect portion 71 and inside the first coil 8. As a constituent material of the contrast marker 15, a material having X-ray contrast properties (X-ray opaque material) is used. Examples of such a material include noble metals such as gold, platinum, and tungsten, or alloys containing them (for example, platinum-iridium alloys). The contrast marker 15 may be provided on the surface of the first coil 8 by plating or the like.

  Further, the tip of the defect portion 71 is located near the boundary between the second coil 9 having contrast properties and the first coil 8 having low contrast properties (near the fixing material 12). Under X-ray fluoroscopy, the contrast-enhanced second coil and the contrast marker 15 are mainly contrasted, so the position of the defect portion 71 between them, particularly the longitudinal region of the defect portion 71 is specified. can do.

  Further, instead of the second coil 9 and the contrast marker 15, the balloon is fixed by covering the surface of the portion corresponding to the region of the defect portion 71 of the first coil 8 with a high contrast material such as gold. Can be grasped by an X-ray contrast image.

  FIG. 4 is a longitudinal sectional view showing a fourth embodiment of the medical wire of the present invention. Hereinafter, the fourth embodiment will be described with a focus on differences from the third embodiment described above, and description of similar matters will be omitted.

  The medical wire 1 according to the fourth embodiment is such that a slipping layer 7 is provided with an inactive portion 72 whose slipping function is inferior to other portions of the slipping layer 7 in place of the defect portion 71. The rest of the configuration is the same as in the third embodiment.

  In the inactive portion 72, the frictional resistance (sliding resistance) of the balloon catheter 20 with respect to the outer surface of the balloon 21 is larger than that in other portions of the slipping layer 7. Therefore, the balloon 21 that has come into contact with the deactivated portion 72 is prevented from sliding (mainly moving in the axial direction), and the balloon 21 is securely fixed.

  For this reason, the coating layer 16 has an increase in sliding resistance in the middle of its longitudinal direction, in which the sliding resistance is greater than other parts of the coating layer 16 (parts other than the deactivation portion 72 of the sliding layer 7). The deactivation part 72 corresponds to this sliding resistance increasing part.

The lengths L ₁ and L _{2 of} the deactivated part 72, the formation method of the deactivated part 72, and the like are the same as in the first embodiment.

  Next, an example of a method for using the medical wire 1 of the present invention will be described. 5-8 is a figure which shows the use condition in the case of using the medical wire 1 of this invention with a balloon catheter in PTCA operation, respectively.

  5 to 8, 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 (lesion). Reference numeral 30 is a guiding catheter for reliably guiding the balloon catheter guiding guide wire 35 and the medical wire 1 of the present invention from the femoral artery to the right coronary artery, and reference numeral 20 is a balloon that can be expanded and contracted at its distal end. The balloon catheter for dilatation of a stenosis part having 21.

  First, an X-ray contrast medium is discharged from the distal opening of the guiding catheter 30 and injected into the right coronary artery 50 to confirm the position of the vascular stenosis 70.

  In this state, as shown in FIG. 5, the tip of the balloon catheter guiding guide wire 35 is projected from the tip of the guiding catheter 30 and inserted into the right coronary artery 50 through the right coronary artery opening 60. Further, the guide wire 35 for guiding the balloon catheter is advanced and inserted into the right coronary artery 50 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.

  Next, as shown in FIG. 6, the distal end of the medical wire 1 of the present invention 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 medical wire 1 is advanced and inserted into the right coronary artery 50 from the distal end, and stopped at a position where the distal end slightly exceeds the vascular stenosis 70. Under X-ray fluoroscopy, while confirming the defect portion 71 (or inactivated portion 72) of the medical wire 1, the medical wire 1 is slightly advanced and retracted so that the defect portion 71 (or inactivated portion 72) becomes a vascular stenosis portion. Alignment is performed so as to match (overlap) 70.

  As described above, the slippery layer 7 is formed on the outer surface of the medical wire 1 and exhibits slipperiness when wet. Therefore, insertion of the medical wire 1 into the right coronary artery 50, advance / retreat operation, etc. can be performed smoothly, quickly and safely. Moreover, since the position of the defect | deletion part 71 (or deactivation part 72) can be grasped | ascertained by the contrast markers 4 and 15, the 2nd coil 9, etc., the said position alignment can be performed easily and reliably.

  Next, as shown in FIG. 7, the tip of the balloon catheter 20 inserted from the proximal end side of the guide wire 35 for guiding the balloon catheter is protruded from the tip of the guiding catheter 30, and further, the guide wire 35 for guiding the balloon catheter is provided. And then inserted into the right coronary artery 50 through the right coronary artery opening 60, and stops when the balloon 21 reaches the position of the vascular stenosis 70. At this time, the balloon 21 is in a deflated state.

  Next, as shown in FIG. 8, a balloon dilating fluid is injected from the proximal end side of the balloon catheter 20 to dilate the balloon 21 and dilate the blood vessel stenosis part 70. By this operation, the deposit such as cholesterol deposited on the blood vessel of the blood vessel stenosis portion 70 is physically pushed and spread, and blood flow inhibition can be solved.

  When the balloon 21 is expanded, the defect portion 71 (or the deactivation portion 72) having a higher frictional resistance is in contact with the outer surface of the balloon 21, and the defect portion 71 ( Alternatively, the deactivation portion 72) is sandwiched. Thereby, the movement in the longitudinal direction due to the sliding of the balloon 21 is prevented, and the balloon 21 is securely fixed at an appropriate position, so that the vascular stenosis portion 70 can be reliably expanded.

  As mentioned above, although illustrated each embodiment of the medical wire of this invention, this invention is not limited to these, Each part which comprises a medical wire is arbitrary which can exhibit the same function. It can be replaced with that of the configuration. Moreover, arbitrary components may be added. Further, the use of the medical wire of the present invention is not limited to the case where it is used in the PTCA operation described above.

It is a longitudinal section showing a 1st embodiment of a medical wire of the present invention. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the medical wire of this invention. It is a longitudinal cross-sectional view which shows 3rd Embodiment of the medical wire of this invention. It is a longitudinal cross-sectional view which shows 4th Embodiment of the medical wire of this invention. It is a figure for demonstrating the use condition of the medical wire of this invention. It is a figure for demonstrating the use condition of the medical wire of this invention. It is a figure for demonstrating the use condition of the medical wire of this invention. It is a figure for demonstrating the use condition of the medical wire of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Medical wire 10 Wire main body 2 1st wire part 25 Outer diameter taper part 3 2nd wire part 4 Contrast marker 5 Covering layer 6 Covering layer 7 Lubricating layer 71 Deletion | deletion part 72 Deactivation part 8 1st coil 9 2nd coil 11, 12, 13 Fixing material 14 Junction 15 Contrast marker 16 Covering layer 20 Balloon catheter 21 Balloon 30 Guiding catheter 35 Guide wire for guiding the balloon catheter 40 Aortic arch 50 Right coronary artery 60 Right coronary artery opening 70 Vascular constriction

Claims (3)

A wire body having a linear first wire portion disposed on a distal end side and a linear second wire portion disposed on a proximal end side of the first wire portion;
A coating layer covering at least the outer periphery of the first wire portion;
A medical wire having a slipping layer formed on the outer surface of the covering layer,
The slipping layer has a deficient part in which a part of the slipping layer is lost in the middle of the longitudinal direction,
The medical wire according to claim 1, wherein the defect portion is in contact with an outer surface of a balloon of a balloon catheter inserted into a blood vessel . A wire body having a linear first wire portion disposed on a distal end side and a linear second wire portion disposed on a proximal end side of the first wire portion;
A coating layer covering at least the outer periphery of the first wire portion;
A medical wire having a slipping layer formed on the outer surface of the covering layer,
The slippery layer has a deactivation part in the middle of its longitudinal direction, the slippery function being inferior to other parts of the slippery layer,
The medical wire according to claim 1, wherein the inactive portion is in contact with an outer surface of a balloon of a balloon catheter inserted into a blood vessel . A wire body having a linear first wire portion disposed on a distal end side and a linear second wire portion disposed on a proximal end side of the first wire portion;
A medical wire having a coating layer covering at least the outer periphery of the first wire portion,
The covering layer has a sliding resistance increasing portion in the middle of its longitudinal direction, in which the sliding resistance of the balloon catheter with respect to the balloon is larger than other portions of the covering layer,
The medical wire, wherein the sliding resistance increasing portion is in contact with an outer surface of a balloon of the balloon catheter inserted in a blood vessel .

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