JP2011177392A - Guide wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a guide wire which has excellent flexibility at a distal end part, is capable of forming a coating layer with a flat and smooth outer surface, and is excellent in operability and safety. <P>SOLUTION: The guide wire includes a flexible wire body composed by bonding a first wire and a second wire arranged on the proximal end side of the first wire, and a spiral coil 4. The coil 4 has an outer diameter/inner diameter fixed part, a tapered part, and an outer diameter/inner diameter fixed part 41 in the order from the proximal end side to the distal end side. In the outer diameter/inner diameter fixed part 41 of the coil 4, the shape of a part 402 on the outer peripheral side of a wire 40 and the shape of a part 401 on the inner peripheral side are different from each other. Then, in the outer diameter/inner diameter fixed part 41, the average value R2 of the curvature radius of the part 402 on the outer peripheral side of the wire 40 on the cross section of the wire 40 is set to be larger than the average value R1 of the curvature radius of the part 401 on the inner peripheral side. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a guide wire.

  The guide wire can be used for the treatment of a site where surgical operation is difficult, such as PTCA (Percutaneous Transluminal Coronary Angioplasty), or for the purpose of minimally invasive to the human body, or cardiovascular Used to guide catheters used for imaging and other examinations. 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.

  Also, in PTA (Percutaneous Transluminal Angioplasty), in order to open a stenosis (occlusion) formed in a blood vessel such as femoral, iliac, linal, shunt, etc. Similarly, the tip of the balloon catheter is guided to the vicinity of the vascular stenosis using a guide wire.

  Blood vessels that require PTCA, PTCA, etc. are intricately curved, and the guide wire used when inserting the balloon catheter into the blood vessel has flexibility and resilience against moderate bending, and manipulation at the proximal end. For example, pushability and torque transmission properties (collectively referred to as “operability”) for transmission to the side, kink resistance (bending resistance), and the like are required. Among these characteristics, as a structure for obtaining moderate flexibility, there is a structure in which a metal coil that can be flexibly bent is installed around a core material (wire body) at the tip of a guide wire. (For example, refer to Patent Document 1). The coil is formed by spirally winding a wire having a circular cross section.

  However, the conventional guide wire has a drawback that the outer diameter of the distal end portion of the guide wire is increased because the cross-sectional shape of the wire constituting the coil is circular.

  Moreover, since the cross-sectional shape of the wire is circular, the rigidity of the distal end portion of the guide wire becomes insufficient. That is, when the distal end portion of the guide wire passes through the vascular stenosis portion or the vascular bend portion, if the cross-sectional shape of the wire is circular, the movable region (movable range) between adjacent wires at the distal end portion Is wide, the tip is easy to bend and becomes flexible. As a result, the pushability of the guide wire is reduced, and the distal end portion thereof may not easily pass through the vascular stenosis part or the vascular bending part.

  Further, when the outer surface of the coil is covered with a hydrophilic lubricating layer, irregularities due to the shape of the outer surface of the coil are formed on the outer surface of the hydrophilic lubricating layer, whereby the lumen of the blood vessel wall or catheter And the contact area between the hydrophilic lubricating layer and the sliding property of the guide wire are reduced.

  Patent Document 2 discloses a guide wire that includes a coil formed by winding a wire in a spiral shape and a core member that is movably installed in the coil. The guide wire coil includes a proximal segment (first segment) provided on the proximal side, a distal segment (second segment) provided on the distal side, a proximal segment, and a distal segment. And a tapered portion provided between the two. The outer diameter of the coil is smaller in the distal end side segment than in the proximal end side segment, and gradually decreases toward the distal end in the tapered portion. As a result, the transverse hardness of the distal segment is smaller than that of the proximal segment. In addition, adjustment of the outer diameter of the coil is performed by polishing the outer peripheral side of the tapered portion and the distal end side segment. On the other hand, the inner diameter of the coil is the same in all of the distal end side segment, the tapered portion, and the proximal end side segment, and is constant along the axial direction.

  However, the guide wire described in Patent Document 2 has a drawback that the pushability of the tip portion is low because the core member is configured to be movable in the coil. Even if the core member is moved to the tip and operated, the torque transmission force becomes low because the leading edge and the core member are not fixed.

JP 2007-135645 A Japanese Patent No. 4198459

  The present invention has been devised in order to achieve the contradictory purpose of making the tip portion thin and maintaining the tip portion rigidity at an appropriate level.

  An object of the present invention is to provide a guide wire that can form a coating layer having good flexibility and a smooth outer surface at the distal end portion, and is excellent in operability and safety.

Such an object is achieved by the present inventions (1) to (7) below.
(1) a wire body made of a flexible core material;
A guide wire that is installed so as to cover the tip of the wire body and includes a coil formed by winding a wire in a spiral shape;
The coil has a constant inner diameter portion having a constant inner diameter on the distal end side thereof, and a tapered portion in which the inner diameter gradually decreases in the distal direction on the proximal end side of the constant inner diameter portion,
The guide wire characterized in that the constant inner diameter portion has an average value of a radius of curvature of an outer peripheral portion of the wire in a cross section of the wire larger than an average value of a radius of curvature of an inner peripheral portion.

(2) The guide wire according to (1), wherein an outer surface of the coil is covered with a hydrophilic lubricating layer made of a hydrophilic material.

(3) The hydrophilic lubricating layer forms a substantially smooth outer surface on the outer surface of the constant inner diameter portion, and forms wavy irregularities on the outer surface of the tapered portion (1) or (2) Guide wire as described in.

(4) In the tip portion of the wire body, the distance between the outer surface of the wire body and the inner surface of the coil is configured to be substantially constant along the longitudinal direction of the wire body. (1) The guidewire according to any one of (3).

(5) The wire main body has a main body side taper portion whose outer diameter gradually decreases in the front end direction on the front end side thereof,
(1) thru | or (1) thru | or the said taper part of the said coil is located in the said main body side taper part, and the said internal diameter fixed part of the said coil is located in the site | part of the front end side rather than the said main body side taper part of the said wire main body. 4) The guide wire according to any one of the above.

(6) The guide wire according to any one of (1) to (5), wherein the constant inner diameter portion has a smaller deformable region in the circumferential direction than the tapered portion.

(7) The inner diameter constant portion has a constant outer diameter of the coil, and the tapered portion has any one of the above (1) to (6) in which the outer diameter of the coil is gradually reduced in the distal direction. Guide wire as described in.

  In the guide wire of the present invention, it is preferable that, in the constant inner diameter portion, the average value of the radius of curvature of the outer peripheral portion of the wire in the cross section of the wire is not infinite.

  In the guide wire of the present invention, it is preferable that the constant inner diameter portion is arranged such that the wire rod becomes rougher along the axial direction of the coil than the tapered portion.

  In the guide wire of the present invention, in the constant inner diameter portion, the wire may be arranged so as to be rougher along the axial direction of the coil than a portion on the proximal end side with respect to the tapered portion of the coil. preferable.

  In the guide wire of the present invention, it is preferable that the two adjacent wires are separated from each other in the constant inner diameter portion.

  In the guide wire of the present invention, it is preferable that the two adjacent wires are in contact with each other at the constant inner diameter portion.

  In the guide wire of the present invention, it is preferable that two adjacent wires are in contact with each other at the tapered portion.

  In the guide wire of the present invention, it is preferable that two adjacent wires are in contact with each other at a base end side of the tapered portion of the coil.

  In the guide wire of the present invention, in the constant inner diameter portion, the shape of the wire in the cross section is noncircular, and the surface shape of the inner peripheral side portion in the cross section of the wire is arcuate. It is preferable.

  In the guide wire of the present invention, in the constant inner diameter portion, the shape of the wire in the cross section is noncircular, and the surface shape of the outer peripheral side portion in the cross section of the wire is an arc shape. Is preferred.

  In the guide wire of the present invention, it is preferable that the taper portion has a circular shape in a cross section of the wire.

  In the guide wire of the present invention, it is preferable that the cross-sectional shape of the wire material is a circular shape at a position on the proximal end side of the tapered portion of the coil.

  According to the present invention, since the guide wire has the wire body and the coil, the operability is excellent. The coil has a constant inner diameter portion and a tapered portion, and by providing a wire body having an outer shape corresponding to the inner shape of the coil, the guide wire obtains good flexibility at the tip portion, The followability and safety to a biological lumen (body cavity) such as a blood vessel can be improved, and bending and the like can be prevented.

  In particular, in the constant inner diameter portion on the tip side of the coil, in the cross section of the wire constituting the coil, the average value of the radius of curvature of the outer peripheral portion of the wire is larger than the average value of the radius of curvature of the inner peripheral portion. By setting, the outer diameter can be reduced without changing the inner diameter of the coil, and appropriate rigidity can be maintained at the tip.

  In addition, when the distal end portion of the guide wire passes through a constricted portion such as a blood vessel or a curved portion, the adjacent wire rods hardly slip at the distal end portion, and the adjacent wire rods are prevented from shifting. Thereby, the pushability of the guide wire is improved, and the distal end portion can be easily passed through the narrowed portion and the curved portion.

  Also, when the outer surface of the coil is covered with a hydrophilic lubricating layer, the outer surface of the hydrophilic lubricating layer at the constant inner diameter portion can be smoothed, thereby increasing the contact area of the hydrophilic lubricating layer and guiding the guide. The slidability of the wire can be improved.

It is a longitudinal cross-sectional view which shows 1st Embodiment of the guide wire of this invention. It is a cross-sectional view which shows the structural example of the wire which comprises the coil of the guide wire shown in FIG. It is a cross-sectional view which shows the other structural example of the wire which comprises the coil of the guide wire shown in FIG. It is a longitudinal cross-sectional view which shows the coil of the guide wire shown in FIG. 1, and a hydrophilic lubricating layer. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the guide wire of this invention.

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

<First Embodiment>
1 is a longitudinal sectional view showing a first embodiment of the guide wire of the present invention, FIG. 2 is a transverse sectional view showing a configuration example of a wire constituting the coil of the guide wire shown in FIG. 1, and FIG. FIG. 4 is a cross-sectional view showing another configuration example of the wire constituting the coil of the guide wire shown in FIG. 1, and FIG. 4 is a vertical cross-sectional view showing the coil of the guide wire and the hydrophilic lubricating layer shown in FIG.

  In the following description, the left side in FIGS. 1 to 3 is referred to as “tip”, the right side is “base end (rear end)”, the upper side is “upper”, and the lower side is “lower”. Further, in FIG. 1, for easy understanding, the length direction of the guide wire is shortened and the thickness direction of the guide wire is exaggerated and schematically illustrated, and the ratio of the length direction to the thickness direction is illustrated. Is different from the actual.

  A guide wire 1 shown in FIG. 1 is a guide wire for a catheter that is used by being inserted into the lumen of a catheter (including an endoscope), and includes a first wire 2 disposed on the distal end side, and a first wire 2. A flexible wire body 10 formed by joining (connecting) the second wire 3 disposed on the proximal end side of the wire and a spiral coil 4 are provided. The total length of the guide wire 1 is not particularly limited, but is preferably about 200 to 5000 mm. Further, the outer diameter of the guide wire 1 is not particularly limited, but it is usually preferably about 0.2 to 1.2 mm.

  The first wire 2 is composed of a wire material (core material) having flexibility or elasticity. Although the length of the 1st wire 2 is not specifically limited, It is preferable that it is about 20-1000 mm.

  In the present embodiment, the first wire 2 includes a portion having a constant outer diameter (a constant outer diameter portion) and a tapered portion (the outer diameter gradually decreasing portion) in which the outer diameter gradually decreases in the distal direction. Taper portion). In the illustrated configuration, the first wire 2 includes, in order from the proximal end side to the distal end side, a constant outer diameter portion 25, a tapered portion 24, and a constant outer diameter portion 23 having a smaller outer diameter than the constant outer diameter portion 25. The taper portion (main body side taper portion) 22 and the most distal end portion 21 are provided.

  By having the taper portions 22 and 24, the rigidity (bending rigidity and torsional rigidity) of the first wire 2 can be gradually decreased toward the distal end, and as a result, the guide wire 1 is good at the distal end. With such flexibility, followability to a body lumen (body cavity) such as a blood vessel and safety can be improved, and bending and the like can be prevented.

  The taper angle (the reduction rate of the outer diameter) of each of the taper portions 22 and 24 is constant along the longitudinal direction of the wire main body 10 (hereinafter, simply referred to as “longitudinal direction”), but varies along the longitudinal direction. There may be. 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.

  The most advanced portion 21 can be, for example, a constant outer diameter portion having a smaller outer diameter than the constant outer diameter portion 23.

  In addition, the forefront portion 21 may be configured to have a flat plate shape (ribbon shape), for example, and can be used after being deformed (reshaped: shaped) into a desired shape. In general, a guide wire is used by a doctor by bending a distal end portion of a guide wire into a desired shape in advance so that the distal end portion of a guiding catheter or the like corresponds to a blood vessel shape or smoothly guides a blood vessel branch. In some cases, bending the distal end portion of the guide wire into a desired shape is referred to as reshaping. And by providing this forefront part 21, reshaping can be performed easily and reliably, and the operativity at the time of inserting the guide wire 1 in a living body improves markedly.

  Although the length of the most advanced part 21 is not specifically limited, It is preferable that it is about 5-200 mm, and it is more preferable that it is about 10-150 mm. In particular, when the most advanced portion 21 is reshaped and used, if the length of the most advanced portion 21 is too long, the operability of the guide wire 1 may be lowered depending on the constituent material. If the length of 21 is too short, the shape of the distal end portion of the guide wire 1 may not be a desired shape.

  The constituent material (material) of the 1st wire 2 is not specifically limited, For example, various metal materials, such as a Ni-Ti system alloy and stainless steel, can be used, but the alloy (superelastic alloy is shown) which shows pseudoelasticity. Preferably). More preferably, it is a superelastic alloy. Since the superelastic alloy is relatively flexible and has a resilience and is difficult to bend, the guide wire 1 can be sufficiently formed in 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. Even if the first wire 2 repeatedly bends and bends, Since the 1 wire 2 is not bent due to the restoring property, 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 1.

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

  The preferred composition of the superelastic alloy is Ni-Ti alloy such as Ni-Ti alloy of 49-52 atomic% Ni, Cu-Zn alloy of 38.5-41.5 wt% Zn, 1-10 wt% X Cu-Zn-X alloy (X is at least one of Be, Si, Sn, Al, and Ga), 36-38 atomic% Al-Ni-Al alloy, and the like. Of these, the Ni-Ti alloy is particularly preferable. In addition, the superelastic alloy represented by Ni-Ti type alloy is excellent also in adhesiveness, such as the resin coating layer 8 mentioned later.

  The distal end of the second wire 3 is joined (connected) to the proximal end of the first wire 2 (the proximal end of the constant outer diameter portion 25). The second wire 3 is composed of a wire material (core material) having flexibility or elasticity. Although the length of the 2nd wire 3 is not specifically limited, It is preferable that it is about 20-4800 mm, and it is more preferable that it is about 1400-3000 mm.

  The average outer diameter of the second wire 3 is larger than the average outer diameter of the first wire 2. As a result, the guide wire 1 is more flexible on the first wire 2 on the distal end side and more rigid on the second wire 3 on the proximal end side. It is possible to achieve both flexibility and excellent operability (pushability, torque transmission, etc.).

  The method for joining the first wire 2 and the second wire 3 is not particularly limited, and various methods such as welding and brazing can be used. For example, the first wire 2 and the second wire 3 are It is preferable that it is joined by welding.

  Further, the welding method is not particularly limited, and examples thereof include friction welding, butt resistance welding such as spot welding using a laser and upset welding, and the like, because relatively simple and high joint strength can be obtained. Butt resistance welding is particularly preferred.

  The second wire 3 is made of a material different from that of the first wire 2, and in particular, the elastic modulus (Young's modulus (longitudinal elastic modulus), rigidity (transverse elastic modulus), volume elasticity) than the constituent material of the first wire 2. It is preferable that it is made of a material having a high rate. Thereby, moderate rigidity (bending rigidity, torsional rigidity) is obtained for the second wire 3, the guide wire 1 becomes so-called strong and the pushability and torque transmission performance are improved, and more excellent insertion operability. Is obtained.

  The constituent material (material) of the second wire 3 is not particularly limited as long as it is different from the first wire 2, and is stainless steel (for example, SUS304, SUS303, SUS316, SUS316L, SUS316J1, SUS316J1L, SUS405, SUS430, SUS434, Various metal materials such as SUS444, SUS429, SUS430F, SUS302), piano wire, cobalt alloy, pseudoelastic alloy, etc. can be used, but stainless steel or cobalt alloy is preferable, and stainless steel More preferably, it is steel. By configuring the second wire 3 with stainless steel or a cobalt-based alloy, the guide wire 1 can obtain better pushability and torque transmission.

  In the present embodiment, the wire body 10 is obtained by joining the first wire 2 and the second wire 3, but is not limited thereto, and may be configured by, for example, one continuous wire. .

  Further, the coil 4 is installed on the outer periphery of the distal end portion of the wire body 10, that is, on the outer periphery of the most distal end portion 21, the tapered portion 22, and the constant outer diameter portion 23 of the first wire 2. The coil 4 is a member formed by spirally winding (forming) a wire rod (thin wire) 40, and includes a distal end portion of the wire body 10, that is, a distal end portion 21 of the first wire 2, a taper portion 22, and the like. The outer diameter constant portion 23 is installed so as to cover the portion excluding the base end portion (the majority of the outer diameter constant portion 23).

Further, the first wire 2 is inserted through a substantially central portion inside the coil 4.
The coil 4 corresponds to the most distal end portion 21, the taper portion 22 and the constant outer diameter portion 23 of the first wire 2, and has a portion having a constant outer diameter and inner diameter (a constant outer diameter / inner diameter portion), an outer And a tapered portion (outer diameter / inner diameter gradually decreasing portion) (tapered portion) in which the diameter and the inner diameter gradually decrease in the distal direction. In the illustrated configuration, the coil 4 has an outer diameter and an inner diameter that are smaller than the outer diameter / inner diameter constant portion 43, the tapered portion 42, and the outer diameter / inner diameter constant portion 43 in order from the proximal end side to the distal end side. A constant inner diameter portion (constant inner diameter portion) 41 is provided. The outer diameter / inner diameter constant portion 43, the taper portion 42, and the outer diameter / inner diameter constant portion 41 are located at the outer diameter constant portion 23, the taper portion 22 and the most distal end portion 21 of the first wire 2, respectively.

  Further, at the distal end portion of the wire main body 10, the distance between the outer surface of the wire main body (core material) 10 and the inner surface of the coil 4 is configured to be substantially constant along the longitudinal direction. .

  Thus, the 1st wire 2 and the coil 4 are arrange | positioned concentrically, and the front-end | tip part of the guide wire 1 enables a deformation | transformation without a bias | inclination.

  In the illustrated configuration, the two adjacent wire members 40 are in contact with each other without applying an external force to all of the outer diameter / inner diameter constant portion 41, the tapered portion 42, and the outer diameter / inner diameter constant portion 43 of the coil 4. (The wires 40 are arranged densely with no gaps). However, the present invention is not limited to this, and may be configured as follows, for example.

  That is, at the constant outer diameter / inner diameter portion 41 of the coil 4 (at the tip end side of the coil 4), the wire 40 is rougher along the axial direction of the coil 4 than the tapered portion 42 and the outer diameter / inner diameter constant portion 43. It may be arranged. Specifically, in the outer diameter / inner diameter constant portion 41, two adjacent wire rods 40 are separated from each other without applying an external force, and a gap is formed between the wire rods 40. Thereby, the softness | flexibility of the site | part corresponding to the outer diameter and internal diameter fixed part 41 of the guide wire 1 further improves, and followable | trackability and safety | security can be improved. On the other hand, at the tapered portion 42 and the constant outer diameter / inner diameter portion 43 (base end side of the coil 4), it is preferable that two adjacent wire members 40 are in contact with each other in a state where no external force is applied.

  As shown in FIG. 2, in the outer diameter / inner diameter constant portion 41 of the coil 4, the shape of the outer peripheral side portion 402 (shape in the cross section) of the wire 40 and the shape of the inner peripheral side portion 401 are as follows. Different from each other. That is, the shape of the wire 40 in the cross section of the constant outer diameter / inner diameter portion 41 of the coil 4 is noncircular. In the outer diameter / inner diameter constant portion 41, the average value R2 of the radius of curvature of the outer peripheral portion 402 of the wire 40 in the cross section of the wire 40 is larger than the average value R1 of the radius of curvature of the inner peripheral portion 401. It is set large.

  As a result, when the distal end portion of the guide wire 1 tries to bend, the contact area between the adjacent wire members 40 becomes large in the outer diameter / inner diameter constant portion 41, and the distal end portion of the guide wire 1 becomes a vascular stenosis portion or a vascular bend. When passing through the portion, the movable region (the movable range) between the adjacent wire rods 40 at the tip end portion becomes narrow, and the tip portion becomes difficult to bend. That is, the outer diameter / inner diameter constant portion 41 has a smaller deformable region in the circumferential direction than the tapered portion 42, and the distal end portion of the guide wire 1 has appropriate rigidity. As a result, the pushability of the guide wire 1 is improved, and the distal end portion thereof easily passes through the blood vessel stenosis portion or the blood vessel bending portion.

  Further, only the outer diameter can be reduced without changing the inner diameter of the coil 4, whereby the guide wire 1 can be reduced in diameter while ensuring a sufficient space in the coil 4. The shape and size of the wire body 10 can be selectively set.

  Moreover, the unevenness | corrugation of the outer surface of the coil 4 can be made small (for example, the outer surface of the coil 4 can be smooth | blunted), and, thereby, the hydrophilic lubrication layer 7 mentioned later in the outer diameter and internal diameter constant part 41 is mentioned. The outer surface can be smoothed. Thereby, the contact area of the hydrophilic lubricating layer 7 is increased, and the slidability of the guide wire 1 can be improved.

  The inner peripheral portion 401 is a portion having a constant radius of curvature on the inner peripheral side (lower side in FIG. 2) of the wire 40 in the cross section of the wire 40. Further, the outer peripheral portion 402 is a portion that follows the inner peripheral portion 401 of the wire 40 in the cross section of the wire 40.

  In addition, in the outer diameter / inner diameter constant portion 41, the average value R2 of the radius of curvature of the outer peripheral portion 402 of the wire 40 may not be infinite as shown in FIG. As such, it may be infinite.

  First, as shown in FIG. 2, when the average value R2 of the curvature radius of the outer peripheral portion 402 of the wire 40 in the constant outer diameter / inner diameter portion 41 is not infinite, the inner peripheral portion of the cross section of the wire 40 The surface shape of 401 is not particularly limited, but is preferably an arc shape, and the surface shape of the outer peripheral portion 402 is not particularly limited, but is preferably an arc shape.

The R1 is preferably 0.005 mm ≦ R1 ≦ 0.1 mm, and more preferably 0.01 mm ≦ R1 ≦ 0.04 mm.
The R2 is preferably 0.04 mm <R2 <∞.

  As shown in FIG. 3, when the average value R2 of the radius of curvature of the outer peripheral portion 402 of the wire 40 in the outer diameter / inner diameter constant portion 41 is infinite, the inner peripheral side of the cross section of the wire 40 The surface shape of the part 401 is linear, and the surface shape of the part 402 on the outer peripheral side is not particularly limited, but is preferably an arc shape. In this case, the preferred value of R2 is the same as described above.

  Moreover, in the taper part 42 and the constant outer diameter / inner diameter part 43, the shape of the wire 40 is not particularly limited, but the shape of the wire 40 in the cross section is preferably circular. That is, it is preferable that the average value of the radius of curvature of the outer peripheral portion in the cross section of the wire 40 is set equal to the average value of the radius of curvature of the inner peripheral portion in the cross section of the wire 40. By setting the taper portion 42 as described above, the movable region between the adjacent wire members 40 in the taper portion 42 becomes wide, and flexible deformation becomes possible. That is, when the outer diameter / inner diameter constant portion 41 is difficult to bend, the passability of the narrowed portion is improved, and the taper portion 42 has flexibility, thereby improving the followability. As a result, the pushability of the guide wire 1 is improved, and the distal end portion thereof easily passes through the blood vessel stenosis portion or the blood vessel bending portion.

  The wire 40 of the coil 4 is formed by, for example, polishing (grinding) a circular cross-sectional shape. That is, a portion 402 on the outer peripheral side of the wire 40 constituting the constant outer diameter / inner diameter portion 41 of the coil 4 is polished into a predetermined shape. This processing method is not particularly limited, and for example, physical processing (mechanical processing) using a polishing / grinding tool or the like, or chemical processing such as etching or electrolytic polishing (electrolytic processing) can be used.

  In addition, the polishing amount of the wire 40 in the outer diameter / inner diameter constant portion 41 is preferably 50% or less, more preferably about 25 to 40%.

  When the polishing amount of the wire 40 in the constant outer diameter / inner diameter portion 41 exceeds the upper limit value, the contact area between the adjacent wires 40 in the constant outer diameter / inner diameter portion 41 becomes small, and the distal end portion of the guide wire 1 becomes vascular stenosis. When passing through the head part or the blood vessel bending part, the adjacent wire members 40 are easily displaced at the tip part, the tip part is easily bent, the pushability is lowered, and the tip part is not connected to the blood vessel stenosis part or the blood vessel bending part. It becomes difficult to pass. Further, if a strong pushing force is applied from the hand side while the tip is in contact with the blood vessel wall, the coil 4 may be damaged.

  The coil 4 may be formed, for example, by winding a wire 40 having a circular shape in a cross section around the wire body 10 and then polishing the wire 40. It may be formed by winding around the main body 10.

  When polishing after winding the wire 40 around the wire body 10, for example, it is preferable that the coil 4 is pulled and polished along the spiral wire 40 with the coil 4 extended. Thereby, it can grind | polish easily and reliably. Needless to say, the coil 4 may be polished without being pulled.

  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, tungsten, and alloys containing these (for example, platinum-iridium alloy). In particular, when the guide wire 1 is made of an X-ray opaque material such as a noble metal, X-ray contrast can be obtained in the guide wire 1, and the guide wire 1 can be inserted into the living body while confirming the position of the tip under X-ray fluoroscopy. It is possible and preferable. Further, the coil 4 may be composed of different materials on the distal end side and the proximal end side. 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 that relatively transmits X-rays (such as stainless steel). The total length of the coil 4 is not particularly limited, but is preferably about 5 to 500 mm.

  The distal end portion and the proximal end portion of the coil 4 are fixed to the first wire 2 by fixing materials 51 and 53, respectively. The intermediate portion of the coil 4 is fixed to the first wire 2 by a fixing material 52. The fixing materials 51 to 53 are made of solder (brazing material). The fixing materials 51 to 53 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 a body cavity such as a blood vessel, the distal end surface of the fixing material 51 is preferably rounded.

  In the present embodiment, by providing such a coil 4, moderate flexibility is obtained at the distal end portion of the guide wire 1, and the first wire 2 is covered with the coil 4 and has a contact area. Since there are few, a sliding resistance can be reduced and, therefore, the operativity of the guide wire 1 improves more.

  The guide wire 1 also has a resin coating layer 8 that covers all or part of the outer peripheral surface (outer surface) of the wire body 10. In the illustrated configuration, the resin coating layer 8 is provided on the outer periphery of the tapered portion 24 and the constant outer diameter portion 25 of the first wire 2 and the second wire 3, respectively.

  The resin coating layer 8 can be formed for various purposes. As an example, the operability of the guide wire 1 is reduced by reducing the friction (sliding resistance) of the guide wire 1 and improving the slidability. May be improved.

  In order to reduce the friction (sliding resistance) of the guide wire 1, the resin coating layer 8 is preferably made of a material that can reduce friction as described below. Thereby, the frictional resistance (sliding resistance) with the inner wall of the catheter used together with the guide wire 1 is reduced, the slidability is improved, and the operability of the guide wire 1 in the catheter becomes better. Further, since the sliding resistance of the guide wire 1 is lowered, when the guide wire 1 is moved and / or rotated in the catheter, the guide wire 1 is kinked (bent) or twisted, in particular, with the first wire 2 and the second wire. Kinks and twists in the vicinity of the joint portion (joint surface) 6 of the two wires 3 can be more reliably prevented.

  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.) or a composite material thereof.

  In particular, when a fluorine-based resin (or a composite material containing the same) is used, the frictional resistance (sliding resistance) between the guide wire 1 and the inner wall of the catheter is more effectively reduced, and slidability is improved. This can improve the operability of the guide wire 1 in the catheter. In addition, this makes it possible to more reliably prevent kinking (bending) and twisting of the guide wire 1, particularly kinking and twisting in the vicinity of the welded portion, when the guide wire 1 is moved and / or rotated in the catheter.

  In addition, when a fluororesin (or a composite material containing the same) is used, the wire body 10 can be coated with the resin material heated by a method such as baking or spraying. Thereby, the adhesiveness between the wire body 10 and the resin coating layer 8 is particularly excellent.

  Further, when the resin coating layer 8 is composed of a silicone resin (or a composite material containing the same), even when the resin coating layer 8 is formed (covered on the wire body 10) without heating, It is possible to form the resin coating layer 8 that is firmly and firmly adhered to the wire body 10. That is, when the resin coating layer 8 is made of a silicone resin (or a composite material containing the same), a reaction-curing material or the like can be used, and therefore the resin coating layer 8 is formed at room temperature. be able to. Thus, by forming the resin coating layer 8 at room temperature, the coating can be easily performed and the guide wire can be operated in a state in which the bonding strength at the bonding portion 6 is sufficiently maintained.

The thickness of the resin coating layer 8 is not particularly limited, and is appropriately determined in consideration of the purpose of forming the resin coating layer 8, the constituent material, the forming method, and the like. Usually, the thickness (average) of the resin coating layer 8 is used. Is preferably about 1 to 100 μm, and more preferably about 1 to 30 μm. If the thickness of the resin coating layer 8 is too thin, the purpose of forming the resin coating layer 8 may not be sufficiently exhibited, and the resin coating layer 8 may be peeled off. Moreover, when the thickness of the resin coating layer 8 is too thick, the physical characteristics of the wire body 10 may be affected, and the resin coating layer 8 may be peeled off.
The resin coating layer 8 may be a single layer or a laminate of two or more layers.

  In the present invention, the outer peripheral surface (surface) of the wire body 10 is subjected to a treatment (roughening, chemical treatment, heat treatment, etc.) for improving the adhesion of the resin coating layer 8, An intermediate layer that can improve the adhesion can also be provided.

  Further, it is preferable that a hydrophilic material is coated on at least the outer surface of the guide wire 1. In the present embodiment, the outer peripheral surface (outer surface) of the coil 4 of the guide wire 1 is covered with a hydrophilic lubricating layer 7 made of a hydrophilic material. As a result, the hydrophilic material is wetted to produce lubricity, the friction (sliding resistance) of the guide wire 1 is reduced, and the slidability is improved. Therefore, the operability of the guide wire 1 is improved. In particular, as shown in FIG. 4, the portion 402 on the outer peripheral side of the wire 40 in the constant outer diameter / inner diameter portion 41 has a large radius of curvature, so that hydrophilic lubrication in the constant outer diameter / inner diameter portion 41 is achieved. The outer surface of layer 7 forms a substantially smooth outer surface. Therefore, the contact area with the inner wall of a blood vessel wall or a catheter is increased, and lubricity is improved. Furthermore, since the taper portion 42 continuing to the base end side of the outer diameter / inner diameter constant portion 41 is formed of a circular wire 40, the outer surface of the hydrophilic lubricating layer 7 in the taper portion 42 is substantially A wavy (corrugated) outer surface is formed. Thereby, when passing through a comparatively narrow stenosis part, it becomes possible to push in while narrowing the stenosis part safely.

  Examples of the hydrophilic material (the constituent material of the hydrophilic lubricating layer 7) include, for example, a cellulose-based polymer material, a polyethylene oxide-based polymer material, and a maleic anhydride-based polymer material (for example, methyl vinyl ether-maleic anhydride copolymer). Maleic anhydride copolymer), acrylamide polymer materials (for example, polyacrylamide, polyglycidyl methacrylate-dimethylacrylamide (PGMA-DMAA) block copolymer), water-soluble nylon, polyvinyl alcohol, polyvinylpyrrolidone, etc. Is mentioned.

  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 1. Thereby, the slidability of the guide wire 1 is improved, and the operability of the guide wire 1 in the catheter becomes better.

  As described above, according to the guide wire 1, the distal end portion has a good flexibility and is excellent in operability. In particular, the guide wire has excellent pushability when the distal end portion of the guide wire 1 passes through the vascular stenosis portion or the vascular bending portion, and the distal end portion can easily pass through the vascular stenosis portion or the vascular bending portion. .

Second Embodiment
FIG. 5 is a longitudinal sectional view showing a second embodiment of the guide wire of the present invention. In the following description, the left side in FIG. 5 is “tip”, the right side is “base end (rear end)”, the upper side is “upper”, and the lower side is “lower”. Further, in FIG. 5, for ease of understanding, the length direction of the guide wire is shortened, the thickness direction of the guide wire is exaggerated, and the ratio of the length direction to the thickness direction is schematically illustrated. Is different from the actual.

  Hereinafter, the second embodiment will be described with a focus on the differences from the first embodiment described above, and the description of the same matters will be omitted.

  As shown in FIG. 5, the guide wire 1 of 2nd Embodiment has the resin coating layer 9 which covers the outer peripheral surface (outer surface) of a coil.

  The resin coating layer 9 can be formed for various purposes. For example, the resin coating layer 9 can be provided for the purpose of improving safety when the guide wire 1 is inserted into a blood vessel or the like. For this purpose, the resin coating layer 9 is preferably made of a material having a high flexibility (soft material, elastic material).

  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 elastomers such as elastomers, various rubber materials such as latex rubber and silicone rubber, or composite materials in which two or more thereof are combined.

  In particular, when the resin coating layer 8 is made of the above-described thermoplastic elastomer or various rubber materials, the flexibility of the distal end portion of the guide wire 1 is further improved. It is possible to more reliably prevent damage to the inner wall and the like, and the safety is extremely high.

  The thickness of the resin coating layer 9 is not particularly limited, and is appropriately determined in consideration of the purpose of forming the resin coating layer 9, the constituent material, the forming method, and the like. Usually, the thickness (average) of the resin coating layer 9 is used. Is preferably about 1 to 100 μm, and more preferably about 1 to 30 μm. If the thickness of the resin coating layer 9 is too thin, the purpose of forming the resin coating layer 9 may not be sufficiently exhibited, and the resin coating layer 9 may be peeled off. Moreover, when the thickness of the resin coating layer 9 is too thick, the physical characteristics of the wire body 10 may be affected, and the resin coating layer 9 may be peeled off.

The resin coating layer 9 may be a single layer or a laminate of two or more layers.
According to this guide wire 1, the same effect as the first embodiment described above can be obtained.

  In the guide wire 1, for example, in the outer diameter / inner diameter constant portion 41 of the coil 4, the two adjacent wire rods 40 are separated from each other without applying an external force, and a gap is formed between the wire rods 40. In the case where the resin coating layer 9 is formed, the resin coating layer 9 enters the gap, whereby the adhesion between the coil 4 and the resin coating layer 9 is particularly excellent.

  As mentioned above, although the guide wire of this invention was demonstrated based on embodiment of illustration, this invention is not limited to this, The structure of each part is substituted by the thing of the arbitrary structures which have the same function. be able to. In addition, any other component may be added to the present invention.

  Further, the present invention may be a combination of any two or more configurations (features) of the above embodiments.

DESCRIPTION OF SYMBOLS 1 Guide wire 10 Wire main body 2 1st wire 21 The most advanced part 22, 24 Tapered part 23, 25 Constant outer diameter part 3 2nd wire 4 Coil 40 Wire 401 Inner side part 402 Outer side part 41, 43 Outer diameter -Internal diameter constant part 42 Tapered part 5 Intermediate member 51-53 Fixing material 6 Joining part 7 Hydrophilic lubrication layer 8, 9 Resin coating layer

Claims (7)

A wire body made of a flexible core;
A guide wire that is installed so as to cover the tip of the wire body and includes a coil formed by winding a wire in a spiral shape;
The coil has a constant inner diameter portion having a constant inner diameter on the distal end side thereof, and a tapered portion in which the inner diameter gradually decreases in the distal direction on the proximal end side of the constant inner diameter portion,
The guide wire characterized in that the constant inner diameter portion has an average value of a radius of curvature of an outer peripheral portion of the wire in a cross section of the wire larger than an average value of a radius of curvature of an inner peripheral portion.   The guide wire according to claim 1, wherein an outer surface of the coil is covered with a hydrophilic lubricating layer made of a hydrophilic material.   3. The guide wire according to claim 1, wherein the hydrophilic lubricating layer forms a substantially smooth outer surface on the outer surface of the constant inner diameter portion, and forms wavy irregularities on the outer surface of the tapered portion.   The distance between the outer surface of the said wire main body and the inner surface of the said coil is comprised so that it may become substantially constant along the longitudinal direction of the said wire main body in the front-end | tip part of the said wire main body. 4. The guide wire according to any one of 3. The wire main body has a main body side taper portion whose outer diameter gradually decreases in the front end direction on the front end side thereof,
The taper portion of the coil is located in the main body side taper portion, and the constant inner diameter portion of the coil is located in a portion of the wire main body on the tip side of the main body side taper portion. A guide wire according to any one of the above.   The guide wire according to any one of claims 1 to 5, wherein the constant inner diameter portion has a smaller deformable region in the circumferential direction than the tapered portion.   The guide wire according to any one of claims 1 to 6, wherein the constant inner diameter portion has a constant outer diameter of the coil, and the tapered portion gradually decreases the outer diameter of the coil in a distal direction.

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