JP4502294B2 - Medical guidewire - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a medical guide wire used for introducing a catheter into the cardiovascular system.
[0002]
[Prior art]
For the purpose of angiography, when inserting a catheter with a very thin flexible tube into a blood vessel, or when inserting a balloon catheter into a blood vessel for treatment of a coronary artery occlusion site, the catheter must be inserted safely. to, the medical guide wire comprising a flexible wire is used and Kokoku 4-25024 JP-Kokoku 4 - there is a known example shown in 292175 JP.
[0003]
The medical guide wire 1 (hereinafter simply referred to as the guide wire 1) (see FIG. 7) is a blood vessel 9 of a complicated path that is twisted into a linear form made of a main wire 2 of flexible fine wires. Since it is inserted into the branch blood vessel 9A from the distal end portion 3, soft flexibility and vertical loadability (buckling resistance) against the load in the traveling direction are required, and further, while rotating the rear end portion 5 located outside the body Since it is inserted into the blood vessel and advanced, the torsional rigidity corresponding to the rotation and the high mechanical properties that have the steering property that the direction of the distal end portion 3 in the blood vessel can be operated by the operation of the rear end portion 5 are required. The tip portion 3 is required to be flexible enough to function as a leading portion for insertion into a blood vessel and to be restored from bending deformation. have.
[0004]
That is, for example, when inserting into the branch blood vessel 9A, a pre-shaped portion 8 is formed by plastically deforming a part of the distal end portion 3 into a "<" shape with a fingertip or the like, and the pre-shaped portion 8 is inserted into the blood vessel. When the vicinity of the branch point of the branch blood vessel 9A to be inserted is reached, an operation of rotating the guide wire 1 to introduce the pre-ape portion 8 into the branch blood vessel 9A is performed, and the guide wire 1 is inserted into the branch blood vessel 9A by the introduction operation. The insertion will proceed. Therefore, it is desired that the guide wire 1 has a shape in which the distal end portion 3 is highly flexible, the pre-shaped portion 8 is easily formed, and the rigidity is improved in the direction of the rear end portion 5.
[0005]
As described above, most of the conventional guidewires are the main wire 2 made of a Ni (nickel) -Ti (titanium) superelastic alloy wire or a SUS (stainless steel) material of a rigid alloy material, and the main wire 2 is exposed. It is used in the form of a resin coating such as a Teflon (registered trademark) coating. As a known example of improving the mechanical properties of the guide wire 1 by applying the unique characteristics of the Ni—Ti alloy material / SUS material, “Ni—Ti alloy” disclosed in Japanese Patent Laid-Open No. 9-508538 is disclosed. A guide wire made of a main wire 2 of two types of metal wires connected to a wire and a SUS material wire at an intermediate point in the longitudinal direction of the wire body, and a “SUS material core wire as a sheath body as disclosed in Japanese Patent Application Laid-Open No. 8-000734 Of Ni-Ti alloy cylindrical body ".
[0006]
[Problems to be solved by the invention]
However, the main wire 2 made of a SUS material is “although excellent in rigidity but easy to bend (kinks) and has poor recovery from a bent shape (inferior in kink resistance)”. Main wire 2 made of a Ni—Ti alloy material Has the unique characteristics of “excellent shape memory and good resilience from bending deformation, but poor rigidity (torsion / bending rigidity)”. Some of the properties are sparse and deficient.
[0007]
The known example with resin coating has a structure in which resin coating is applied to the outer periphery of the mirrored surface of the drawn wire, so that the adhesion between the core material and the resin coating is poor, and the twist during use・ Peeling and dropping off of resin coating may occur due to bending stress, resulting in poor safety.
[0008]
On the other hand, the Ni-Ti alloy wire and the SUS material wire combined structure connect and connect the two types of metal wires with a connecting tube member, so that the connecting portion becomes a stepped swelled shape and becomes an intravascular vessel. The insertability is impaired, the mechanical strength of the connecting portion is insufficient, and the connecting process is complicated, resulting in poor moldability. The above-mentioned "Ni-Ti alloy material sheath form" is a composite form of Ni-Ti alloy material and SUS material, but naturally there is a clearance between the core material and the sheath body. Therefore, since the sheath body is deformed by being pressed against the core material by bending resistance when inserted into the bent thin tube, the insertion resistance to the thin tube is increased, making the insertion operation difficult, and there is a possibility that the insertion becomes substantially impossible. . Further, it is extremely difficult to form a long cylindrical Ni—Ti cylindrical body, which is generally limited to an outer diameter = 0.3 mm and an inner diameter = 0.2 mm, and lacks practicality.
[0009]
The present invention provides a high-quality guide wire that solves the above-mentioned problems of the prior art.
[0010]
[Means for Solving the Problems]
The guide wire of the present invention that solves the above technical problems includes a core wire made of one of a rigid alloy material and a superelastic alloy material, and a rigid alloy material and a superelastic alloy material formed on the outer periphery of the core wire material. It has a two-layer structure with a porous form formed by a metal spray layer made of the other alloy material, and has a tapered shape with a tapered end, a long flexible main wire, and a rigid alloy that is fitted and attached to the tip of the main wire. 2 of a core wire made of one of the alloy material and the superelastic alloy material, and a porous form formed by a metal spray layer formed on the outer periphery of the core wire material and made of the other alloy material of the rigid alloy material and the superelastic alloy material. A coil spring having a layer structure and a resin coated on the main wire and the porous form of the coil spring are provided.
[0011]
That is, the guide wire according to the present invention having the above-described configuration includes a superelastic alloy material represented by Ni (nickel) -Ti (titanium) alloy, and a rigid alloy material represented by SUS (stainless steel) material / piano wire. 2 layers of a combination of two different metals, and the outer layer of the two-layer structure is constituted by a metal sprayed layer that can be generated by metal spraying means, and the two kinds of heterogeneous superelastic alloy material and rigid alloy material constituting the two layers It consists of the idea of further improving the required mechanical properties as a guide wire by mutually complementing the mechanical properties.
[0012]
The main wire / coil wire of the two-layer structure is formed in advance with a bus bar in which a metal sprayed layer is formed on a large-diameter wire by a known means, and then the bus bar is drawn to form a two-layer structure with a predetermined diameter. A drawn wire formed into a linear body is mainly used. Then, as an aspect of the basic configuration, a metal sprayed layer is regenerated in the form of providing a resin coating such as Teflon on the main wire of the first invention or in the middle of the diameter drawing process of the wire drawing process. In some cases, a multi-layer metal sprayed layer is formed by redrawing.
[0013]
[Action]
The guide wire according to the first aspect of the present invention has two layers of “a superelastic alloy material having excellent shape memory and kink resistance although lacking rigidity” and “a rigid alloy material having excellent rigidity and flexibility despite being inferior in kink resistance”. Because it is composed of the main wire of the structure, the unique characteristics of the heterogeneous two metals can be achieved by combining the two different kinds of alloy materials into “core material or sprayed layer” combination “size adjustment of core material and sprayed layer”. By complementing each other, the required mechanical characteristics can be further improved, and it is possible to provide various quality guide wires in which the mechanical characteristics are finely adjusted and set in accordance with various vascular and therapeutic situations.
[0014]
And since the metal sprayed layer has a porous form in which microscopic voids exist between the fine particles in the form of aggregated metal fine particles, a hydrophilic polymer applied to the outer periphery of the main wire in order to improve the intravascular insertion property, and this Adhesion retention of antithrombotic agents such as heparin used in combination is good, and further improvement of intravascular insertion and anticoagulation effect can be promoted. Furthermore, the two-layer structure main wire subjected to the wire drawing process has improved rigidity as a wire material due to residual stress due to the wire drawing process, and improved adhesion between the core wire material and the metal sprayed layer due to the compressive force due to the wire drawing process. Thus, the core wire material and the metal sprayed layer function as a substantially integral wire, and the above-described complementary action can be achieved smoothly.
[0015]
On the other hand, gas guide wire is a coil spring that fitted to the tip portion, the so constitutes a coil wire of the two-layer structure, excellent insertability, into a blood vessel of the bent shape and functioning the leading portion of the intravascular insertion In addition to further improving the mechanical properties to satisfy the drawability, the metal sprayed layer on the outer periphery of the coil wire improves the hydrophilic polymer adhesion retention, further improving the above-mentioned insertability and pullout stability. To do.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
First, a guide wire 1 according to an embodiment of the first invention will be described with reference to FIG. That is, the distal end portion 3 which is composed of a main wire 2 of a flexible extra-fine wire body, has a slightly small diameter at the distal end portion of the main wire 2 and is fitted with a coil spring 4 to form a highly flexible flexible form. In the provided guide wire 1, the main wire 2 excluding the tip portion 3 is provided with a “metal sprayed layer 7 of SUS material of rigid alloy material” on the outer periphery of the core wire material 6 made of Ni—Ti alloy which is a superelastic alloy material. It has a two-layer structure.
[0017]
Specifically, the main wire 2 of this two-layer structure (see FIG. 1 (C)) is formed on the outer periphery of the large-diameter Ni—Ti alloy bus 12 with a high-speed SUS material droplet melted and refined by gas flame. A main wire 2A having a metal spray layer 7 (hereinafter referred to as a spray layer 7) formed by a known metal spraying means formed by spraying is formed, and the main wire 2A is then drawn. The SUS material having a thickness of 20 to 150 microns (70 microns in this embodiment) is sprayed on the outer periphery of the core wire 6 made of Ni—Ti alloy material and having an outer diameter D = approximately 0.217 mm. A two-layer structure including the layer 7 is formed.
[0018]
The distal end portion 3 of the main wire 2 is processed into a small-diameter portion obtained by polishing and removing the outer periphery including the sprayed layer 7 and the coil spring 4 is fitted and attached, and the rear end portion that goes out of the body in an intravascular insertion state. At the end of 5, the sprayed layer 7 is removed by polishing.
[0019]
In the guide wire 1 of FIG. 1 embodiment described above, the Ni—Ti alloy core wire 6 and the SUS material sprayed layer 7 are integrated to complement the respective mechanical properties. In the base with the characteristics and rigidity, it is excellent in torque transmission force and rotational transmission, and becomes high quality excellent in insertion into a blood vessel and steering. 1 has a form in which the coil spring 4 is fitted to the main wire 2 made of only the Ni—Ti alloy material, so that it can be bent and deformed when inserted into a bent blood vessel. Good recovery from deformation, excellent insertion advancement function of the distal end portion 3 as a leading portion for insertion into the blood vessel, easy insertion to the blood vessel terminal, and the distal end portion 3 is supplemented by a bent blood vessel, making it difficult to pull out There is no risk of becoming.
[0020]
Further, since the sprayed layer 7 forming the outer periphery is in a porous form, the adhesion retention property of the hydrophilic polymer / antithrombotic agent applied to the outer periphery for improving the intravascular insertion property of the guide wire 1 is good, and the lubricity is further improved. It can improve the coagulation prevention effect while improving. Since the main wire 2 is drawn and thinned, the residual stress caused by the drawing can further complement and adjust mechanical properties such as rigidity, and the core wire 6 and the sprayed layer 7 can be adjusted. The adhesiveness is improved and both function as a substantially integral body, and there is no fear that the thermal spray layer 7 is peeled off by bending deformation stress inserted into the blood vessel, and safety can be secured.
[0021]
Next, another embodiment of the guide wire 1 of the first invention will be described with reference to FIG. That is, in the main wire 2 having a two-layer structure in which the thermal spray layer 7 is provided on the outer periphery of the metal core wire 6, the main wire 2 in FIG. 2 is “the core wire 6 is an SUS material and the spray layer 7 is The Ni-Ti alloy material ", the two-layer material of the embodiment shown in FIG. 1 is a reverse combination, and the thermal spray layer 7 is present in the latter half of the tip 3 where the coil spring 4 is fitted. The main wire 2 in the embodiment of FIG. 2 is also provided with a metal sprayed layer of Ni—Ti alloy material on a large-diameter SUS material bus, and then stretched to reduce the diameter.
[0022]
In the embodiment shown in FIG. 2, the portion that forms the pre-shaped portion 8 is made of the main wire 2 made of only SUS material, so that the pre-shaped portion 8 can be easily processed. Since the main wire 2 excluding the exposed portion of the SUS material has a composite structure of the Ni—Ti alloy material and the SUS material, appropriate mechanical properties can be ensured satisfactorily as required by complementing the characteristics of both metals.
[0023]
Next, another embodiment of the first invention will be described with reference to FIG. That is, in the guide wire 1 provided with a resin coating 10 such as Teflon coating, polyamide, polyurethane, and fluorine resin that wraps the main wire 2, the main wire 2 is also made of “Ni—Ti alloy material” as in the embodiment of FIG. It has a two-layer structure in which a SUS material sprayed layer 7 is provided on the outer periphery of the core wire 6 and has a structure in which only the tip 3 is polished and removed. A coating 10 is applied.
[0024]
Since the main wire 2 has the same two-layer structure as that of the embodiment of FIG. 1, the guide wire 1 of the above embodiment of FIG. 3 has the same “Ni—Ti alloy material and SUS material as those of the embodiment of FIG. Good mechanical properties can be secured by “complementing the mechanical properties of”. And since the adhesion of the resin coating 10 to the thermal spray layer 7 in the surface porous form is improved, there is no possibility that the resin coating 10 is peeled off even if complicated bending and unbending are repeated in the blood vessel. Will improve.
[0025]
In addition, the main wire 2 shown in each of the above embodiments is subjected to a heat treatment at the same time as the strainer processing after the wire drawing and subjected to a linear shape memory treatment of the Ni—Ti alloy material, and the tip which has a bent shape in the blood vessel Consideration is given so that the linear portion including the portion 3 can be pulled out in a shape in which the linear portion is restored to a linear shape by itself and no “bend” remains.
[0026]
Next, a guide wire according to an embodiment of the second invention will be described with reference to FIG. That is, in the guide wire 1 including the distal end portion 3 in which the coil spring 4 is fitted and attached to the distal end portion of the main wire 2, the coil spring 4 has two layers in which the Ni—Ti sprayed layer 7 is provided on the outer periphery of the core wire 6 made of SUS material. It is formed by a coil wire 11 having a structure. Specifically, the coil wire 11 has a two-layer structure in which a Ni—Ti sprayed layer 7 is provided on a large-diameter SUS material wire and the diameter of the coil wire 11 is reduced by wire drawing, as with the main wire 2 in FIG. Accordingly, “the core wire material 6 is made of a Ni—Ti alloy wire and the sprayed layer 7 is made of a SUS material layer”.
[0027]
In the guide wire 1 of FIG. 4 embodiment, the coil spring 4 that greatly contributes to the mechanical properties of the tip 3 is composed of a coil wire 11 having a two-layer metal structure. 3 and further improving the mechanical properties, and by adjusting the contents of the two-layer metal, it is possible to form the tip portion 3 of various quality in which the mechanical properties are finely adjusted and set. And since the outer periphery of the coil spring 4 consists of the thermal sprayed layer 7 of a porous form, the adhesion retention property of a hydrophilic polymer is good, and the blood vessel insertion property and extraction property of the front-end | tip part 3 improve and are stabilized. The coil spring 4 is subjected to shape memory processing after coiling.
[0028]
Next, another embodiment of the second invention will be described with reference to FIG. That is, in the case of using the coil wire of the two-layer structure metal wire similar to the embodiment in FIG. 4, the coil spring 4 in FIG. 3 is a single-layer coil wire 11B of SUS material wire (or Ni-Ti material wire) and 1/3 of the rear end side is the same two-layer structure coil wire 11A as in the embodiment of FIG. Coil wires are welded and connected to form a single coil spring 4.
[0029]
In the embodiment shown in FIG. 5, the coil spring 4 has the above-mentioned three-zone configuration, and the front end of the distal end portion 3 functions as a detection point by radiation at the intravascular position, and the intermediate portion is made of a SUS material that is easily bent. Therefore, it is easy to form the precision portion 8, the rear end portion has a two-layer metal structure, and it has resilience and rigidity by bending, and each portion of the coil spring 4 shares the performance to further improve the various performances of the tip portion 3. You can improve.
[0030]
Next, another form of the main wire 2 and coil wire 11 having a two-layer structure according to the first and second inventions will be described with reference to FIG. That is, in the two-layer structure shown in FIG. 6, the metal sprayed layer 7 made of SUS material or Ni—Ti alloy material is laminated in multiple layers, and the metal sprayed layers 7A and 7B in this laminated form and the core of the SUS material or Ni—Ti wire. It has a two-layer structure made of wire 6. According to the two-layer structure in the form of FIG. The laminated metal sprayed layer is formed by providing the primary sprayed layer 7A on the outer periphery of the bus bar and performing the primary wire drawing, and then forming the secondary sprayed layer 7B on the outer periphery thereof and performing the secondary wire drawing.
[0031]
In addition, the guide wire of this invention is not limited to the said Example, Both the main wire 2 and the coil wire 11 of the coil spring 4 may be made into the composite form of the 1st 2nd invention which makes a 2 layer structure. . As the superelastic alloy material, a known superelastic alloy material such as a ternary alloy material obtained by adding Fe · CO to Ni—Ti or a Cu—Zn—Al alloy material may be used.
[0032]
【The invention's effect】
As described above, the guide wire of the present invention is a main wire / coil spring comprising a wire of “two-layer structure of a superelastic alloy material and a rigid alloy material” in which a metal spray layer is provided on the outer periphery of the metal wire by metal spraying means. Since it has a structure, it should complement each other with the characteristics of the two kinds of heterogeneous alloy materials, and it should be provided as a guide wire such as “flexibility, vertical loadability, torsional rigidity, steering performance, and resistance to residual bending at the tip” These mechanical properties can be further improved, and further quality improvement of the guide wire can be promoted.
[0033]
And by the combination of the alloy material of the two-layer structure and “adjustment of core material diameter / sprayed layer thickness”, the various mechanical characteristics are finely adjusted, and “blood vessel size / blood vessel path” which varies depending on the individual human body.・ Various quality guidewires suitable for various conditions, such as lesion stenosis, adults, and children, can be provided, and the therapeutic and therapeutic effects of vascular treatment using guidewires can be further improved. . There are the above useful effects.
[Brief description of the drawings]
1A and 1B show a medical guide wire according to an embodiment of the first invention, FIG. 1A is a front view thereof, FIG. 1B is a sectional view of DD of FIG. 1A, and FIG. FIG. 2 shows a medical guide wire according to another embodiment of the first invention, in which (A) is a front view thereof, (B) is an EE sectional view of (A), and (C) is an FF of (A). Sectional view [Fig. 3] shows a medical guide wire according to another embodiment of the first invention, (A) is a front view thereof, (B) is a CC sectional view of (A). [Fig. The medical guide wire of an example is shown, (A) is the front view, (B) is CC sectional drawing of (A). FIG. 5 shows the medical guide wire of one Example of 2nd invention, (A) is The front view, (B) is the EE cross section of (A), (B) is the FF cross section of (A), (D) is the GG cross section of (A). Of the coil wire of the second invention Shows a cross-sectional view of the embodiment [7] Conventional medical guide wire, (A) is its front view, (B) is a diagram of its use [EXPLANATION OF SYMBOLS]
DESCRIPTION OF SYMBOLS 1 Medical guide wire 2 Main wire 3 Front-end | tip part 4 Coil spring 5 Rear-end part 6 Core wire 7 Metal sprayed layer 8 Pre-sipe part 9 Blood vessel 10 Resin coating 11 Coil wire 12 Bus line

Claims (1)

A core wire made of one alloy material of a rigid alloy material and a superelastic alloy material, and a porous form formed by a metal spray layer formed on the outer periphery of the core wire material and made of the other alloy material of the rigid alloy material and the superelastic alloy material; A two-layer structure, tapered at the tip, and a long flexible main wire,
A core wire made of one of a rigid alloy material and a superelastic alloy material, fitted to the tip of the main wire, and the other alloy of the rigid alloy material and the superelastic alloy material formed on the outer periphery of the core wire material A coil spring having a two-layer structure with a porous form formed of a metal spray layer made of a material;
A resin coated on the porous form of the main wire and the coil spring;
Medical guide wire comprising the.

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