JP2008043547A - Medical balloon catheter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medical balloon catheter which shows an excellent crossability or the ability to pass through a stenotic site, trackability or the ability to follow tortuous blood vessels, pushability or the ability to transmit a force when the medical balloon catheter is inserted into the blood vessel, and kink-resistance. <P>SOLUTION: The medical balloon catheter includes a proximal end portion tube 9 constituting a balloon dilating lumen 18, an intermediate portion tube 10, a distal end portion tube 12 having the distal end to which a balloon part 10 is fixed, and a guide wire passing tube 6 which has an end opening part at the end, has the distal end to which the balloon part fixed, and is covered by the distal end portion tube and the balloon part. The intermediate portion tube and the distal end portion have the balloon dilating lumen and a core wire 14, and the guide wire passing tube is equipped with an inner layer tube, a reinforcing layer formed by winding a linear body in either a left-handed manner or a right-handed manner in a coiled-shape at least at a part of the inner layer tube, and a resin outer layer for covering the inner layer tube and the reinforcing layer. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a medical balloon catheter used for medical purposes, and more specifically, percutaneous angioplasty (PTA: Percutaneous Transluminal Angioplasty, PTCA: Percutaneous Transluminal Coronary Angioplasty, etc.).

  Conventionally, percutaneous angioplasty using a medical balloon catheter is widely used for the purpose of expanding or treating stenosis or occlusion in the lumen of the blood vessel and restoring or improving blood flow in coronary arteries and peripheral blood vessels. It has been. A typical medical balloon catheter is formed by joining a balloon that can be inflated and deflated by adjusting the internal pressure to the distal end portion of a catheter shaft. Inside the catheter shaft, a lumen through which a guide wire is inserted ( A guide wire lumen) and a lumen for supplying a pressure fluid for adjusting the internal pressure of the balloon (balloon expansion lumen) are provided along the longitudinal direction of the catheter shaft.

  A general operation example of PTCA using such a medical balloon catheter is as follows. First, a guide catheter is inserted from a puncture site such as the femoral artery, brachial artery, and radial artery, and the distal end is placed at the entrance of the coronary artery via the aorta. Next, the guide wire inserted through the guide wire lumen is advanced beyond the stenotic site of the coronary artery, and a medical balloon catheter is inserted along the guide wire to match the balloon with the stenosis. Next, a pressure fluid is supplied to the balloon via a balloon dilatation lumen using an indeflator or the like, and the balloon is inflated to dilate the stenosis. After dilatation treatment of the stenosis, PTCA is terminated by retracting the balloon under reduced pressure and removing it from the body. In this operation example, the use example of the medical balloon catheter by PTCA in the coronary artery stenosis is described. However, the medical balloon catheter is widely applied to the expansion treatment in other blood vessel lumens and body cavities such as the periphery. Yes.

  In such a medical balloon catheter, as shown in FIG. 1 or FIG. 2, the balloon 2 is joined to the tip of the catheter shaft 1, and the hub 3 for supplying pressure fluid for adjusting the internal pressure of the balloon is joined to the catheter shaft 1. It has a structure and is roughly classified into two according to the structure of the catheter shaft 1.

  One is that the guide wire lumen 4 is provided from the proximal end side to the distal end side of the medical balloon catheter, that is, over the entire length of the medical balloon catheter, and the guide wire port 5 is provided in the hub 3. It is an over-the-wire type (OTW type) (FIG. 1). The other is a high-speed exchange type (RX type) in which the guide wire lumen is provided only on the distal end side of the medical balloon catheter and the guide wire port 5 is provided in the middle of the catheter shaft 1 (FIG. 2). .

  The performance required for medical balloon catheters varies widely, but the main performance is the crossability of the stenosis site, the trackability to the bent blood vessel, and the force when inserting the medical balloon catheter into the blood vessel. There are three main categories of pushability. Moreover, kink-resistance is also mentioned as a performance related to pushability.

  Crossability improves by reducing the catheter shaft profile (thickness), but pushability and kink-resistance tend to decrease. In addition, increasing the rigidity of the catheter shaft improves pushability and kink-resistance, but tends to decrease trackability. That is, the above performances are closely related to each other, and it is not easy to improve all the performances. Accordingly, various techniques for improving crossability, pushability, and trackability and improving kink-resistance are disclosed.

  In Patent Document 1, there is provided a medical tube having a flexible inner layer, a reinforcing layer attached to the outside of the inner layer, and a flexible outer layer attached to the outside of the reinforcing layer, The reinforcing layer is a coil layer, at least part of which is composed of a first coil and a second coil that is provided substantially coaxially with the first coil and is wound in a direction opposite to the first coil. Each of the first coil and the second coil is wound in close winding with a gap width between pitches of 0.02 mm or less, and the coil layer extends from the distal end to the proximal end. Adhesive or resin is not bonded to the inner layer and the outer layer for a predetermined length toward the gap between the pitches on the base side of the coil layer in a portion extending from the base end of the medical tube to the predetermined length. Medical treatment characterized by inflow of materials A tube is presented. In addition, a vasodilator catheter using the medical tube is also presented.

  However, this configuration provides pushability and kink-resistance, but the first coil constituting the reinforcing layer and the first coil are provided substantially on the same axis and wound in the opposite direction to the first coil. Since the first coil and the second coil are overlapped with each other, the tube layer can be obtained with only a large thickness. You can't get something expensive. The guide wire passage tube of the vasodilator catheter is required to have a large inner diameter and a small outer diameter, that is, a thin tube. In addition, although an adhesive or a resin material is allowed to flow into the gap between the pitches on the proximal end side of the coil layer, this process is technically cumbersome and difficult. In addition, winding the coil around a tightly wound coil with a gap between the pitches of 0.02 mm or less gives sufficient flexibility to the tip as a vasodilator catheter even if the coil material is selected. That is, it is difficult to obtain trackability.

  Patent Document 2 discloses a balloon catheter assembly including an elongated tubular member having a balloon portion located on the distal side and a shaft portion located on the proximal side, and extends through the balloon portion and the shaft portion. A balloon catheter assembly is presented that includes a central lumen and an alternating braid member extending from the shaft portion distal to the balloon portion.

  Even in this configuration, pushability and kink-resistance can be obtained, but the reinforcing layer is composed of alternately braided members, that is, braided. In this case, since the strands constituting the reinforcing material overlap, the thickness of the tube is reduced. Only thick ones can be obtained. For this reason, a product with high crossability cannot be obtained.

Furthermore, in this document, a so-called OTW type vascular dilatation catheter is presented, but the gap in the braided tubular member functions as a fluid passage from between the inner lumen of the catheter to the balloon itself, or just distal to the balloon. It is complicated as an OTW type vasodilator catheter, such as inflating the balloon by injecting fluid after the part of the valve fits with the valve seat in the lumen and cooperates with the valve seat seen on the core wire or guide wire A core wire or a guide wire having a configuration and a unique valve seat is required, and there is a possibility that a sufficient vasodilator effect cannot be obtained in terms of the complexity of the procedure and the certainty.
Japanese Patent No. 3659664 Japanese Patent No. 3170210

  The main object of the present invention is to provide a medical balloon tube having, as main performances, good passability of a stenosis site, followability to a bent blood vessel, transferability of force when inserting a medical balloon catheter into the blood vessel, and kink resistance Is to provide. In particular, the object of the present invention is to improve the drawbacks of the prior art, such that the guide wire passes but the balloon body is difficult to pass by adding a device to the guide wire passing tube while maintaining their performance. An object of the present invention is to provide a medical balloon tube having improved lesion passage ability. In addition, the present invention provides reachability to the lesioned part and dilatation treatment by giving a stiffness to the distal part of the balloon catheter by combining the entire structure, such as using a reinforcing material for the core wire or the guide wire passing tube. An object of the present invention is to provide a medical balloon tube with high reliability.

The present invention has one or more of the following features.
(1) The present invention includes a proximal end tube (a) and an intermediate tube (b) constituting a lumen for balloon expansion from the proximal end side to the distal end side, and a distal end tube having a balloon portion fixed to the distal end. (C), and a guide wire passing tube (d) having a tip opening at the tip, the balloon being fixed at the distal end, and being covered with the tip tube (c) and the balloon, A balloon balloon lumen and a core wire in the intermediate tube (b) and the distal tube (c), and a proximal portion of the distal tube (c) Has a guide wire port which is a proximal end side opening of the guide wire passage tube (d), and the guide wire passage tube (d) includes an inner layer tube and a small number of the inner layer tube. A medical balloon catheter characterized by comprising a reinforcing layer in which a linear body is wound in a coil shape in only one of the left and right directions and a resin outer layer covering the inner layer tube and the reinforcing layer. .
(2) In a preferred embodiment of the present invention, the inner layer tube of the guide wire passing tube (d) is made of a fluororesin.
(3) In a preferred embodiment of the present invention, the linear body of the guide wire passage tube (d) is a metal strand or a synthetic resin strand.
(4) In a preferred embodiment of the present invention, the resin outer layer of the guide wire passing tube (d) comprises a polyamide elastomer, nylon, polyester, polyester elastomer, polyurethane elastomer, polyolefin, polyimide, polyimide amide, and It consists of any resin material of polyetherimide.

  Other features of the present invention and their advantages will become apparent from the following embodiments and drawings.

  In the medical balloon catheter of the present invention, the guide wire passage tube (d) is reinforced by winding an inner layer tube and a linear body around at least a part of the inner layer tube in only one of the left and right directions. By using a composite tube comprising a layer and a resin outer layer covering the inner layer tube and the reinforcing layer, the distal end portion of the medical balloon catheter has a low profile due to its large inner diameter and smaller outer diameter. In addition, a medical balloon catheter having a particularly improved ability to pass through a narrow lesion can be obtained by coordinating the elasticity of the reinforcing material and the elasticity of the core wire.

  Furthermore, in a preferred embodiment of the present invention, by using a fluororesin for the inner layer tube of the guide wire passage tube, the guide wire passage property is improved, and the outer resin layer of the guide wire passage tube, the vasodilation balloon, However, since it is made of a material having high affinity, the two can be bonded or welded well, and there is an effect that a medical balloon catheter capable of performing a reliable procedure can be obtained.

  Embodiments of a medical balloon catheter according to the present invention will be described below.

1. Overall Structure of Medical Balloon Catheter The medical balloon catheter as an embodiment is a high-speed exchange type (RX type) in which a guide wire passing tube 6 is disposed only at the distal end side of the medical balloon catheter as shown in FIG. It relates to a catheter. FIG. 3 shows the entire medical balloon catheter of the present invention, but the hub 7, the strain relief 8, the proximal tube 9, and the balloon 10 are present.

  Further, FIG. 4 shows a detailed view from the distal portion of the medical balloon catheter, that is, from the balloon to a portion of the proximal tube. In the distal portion, there are a proximal end tube 9, an intermediate tube 11, a distal end tube 12, and a balloon 10 in order from the proximal portion. A guide wire passing tube 6 exists inside the distal end tube 12 and inside the balloon 10. These are bonded by thermal fusion or an adhesive.

  The proximal end tube 9 forms a balloon expansion lumen 18 as seen in the A-A ′ cross section (see FIG. 4), and the position marker 13 may be disposed. You may have a hub provided with the port which supplies a pressure fluid to a balloon in the base end of a base end part (base end side) tube.

  A core wire 14 is disposed in the intermediate tube 11 and the tip tube 12 for the purpose of increasing the rigidity of the distal side of the medical balloon catheter, and a position corresponding to a joint between the intermediate tube and the tip tube. It is fixed with the core wire fixing part 15 which is. B-B 'sectional view (refer to Drawing 4) has balloon expansion lumen 18 by this core wire 14 and middle section tube 11. FIG.

  A guide wire passing tube 6 exists from the inside of the distal end tube 12 to the inside of the balloon 10. In the CC cross-sectional view (see FIG. 4), there is a balloon expansion lumen 18 formed by the guide wire passing tube 6, the core wire 14, and the distal end tube 12. A position marker 16 exists in the balloon 10. A proximal portion of the distal tube 12 has a guide wire port 17 which is a proximal end opening of the guide wire passage tube.

2. Balloon Balloon 10 is fixed to the distal end of tip tube 12 and the distal end of guide wire passing tube 6. A tip opening is provided at the tip of the guide wire passing tube 6.

  The balloon 10 can be inflated and deflated by adjusting the internal pressure. As a manufacturing method of the balloon 10, there are dipping molding, blow molding and the like, and an appropriate method can be selected according to the use application of the medical balloon catheter. In particular, in the case of a medical balloon catheter for the purpose of expanding and treating a stenosis of a blood vessel or a body cavity, blow molding is preferable in order to obtain sufficient pressure resistance. For example, a tubular parison having an arbitrary size is first formed by extrusion molding or the like.

  The tubular parison is placed in a mold having a mold that matches the balloon shape, and stretched in the axial direction and the radial direction by a biaxial stretching process, thereby forming a balloon having the same shape as the mold. In addition, the said biaxial stretching process may be performed on heating conditions, and may be performed in multiple times. Further, the stretching in the axial direction may be performed simultaneously with or before or after the stretching in the radial direction. Furthermore, in order to stabilize the shape and dimensions of the balloon, the balloon may be annealed.

  As shown in FIG. 1 or FIG. 2, the balloon 10 has a straight pipe portion 2a and a joining portion 2b for liquid-tight joining to the distal end side and the proximal end side thereof, and is tapered between the straight pipe portion and the joining portion. It has a part 2c. The dimensions of the balloon 2 are determined by the intended use of the medical balloon catheter. The outer diameter of the straight tube portion 2a when expanded by adjusting the internal pressure is 1.50 to 35.00 mm, preferably 1.50. And the length of the straight pipe portion 2a is 10.00 to 80.00 mm, preferably 10.00 to 60.00 mm.

3. Material The resin material of the tubular parison is not particularly limited. For example, polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane and polyurethane elastomer can be used. You may have the multilayer material by the blend material which mixed the seed | species or more, and the lamination | stacking of 2 or more types.

  The material of the base end tube 9, the intermediate tube 11, and the distal end tube 12 is not particularly limited. That is, polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, polyurethane elastomer and the like can be used.

  The material of the core wire 14 is stainless steel, C—Mn—Si—PS—Cr—Mo—Ni—Fe—X (X = Au, Os, Pd, Re, Ta, Ir, Ru) alloy, C—Mn. -Si-PS-Cr-Mo-Ni-X (X = Au, Os, Pd, Re, Ta, Ir, Ru) alloy, copper, nickel, titanium, piano wire, Co-Cr alloy, Ni-Ti Various alloys such as alloys, Ni—Ti—Co alloys, Ni—Al alloys, Cu—Zn alloys, Cu—Zn—X alloys (for example, X = Be, Si, Sn, Al, Ga), amorphous alloys, etc. Metal wires are used, and among these materials, stainless steel is preferable because it has an appropriate rigidity and is not workable, economical, or toxic. The core wire is preferably tapered so that it gradually becomes thinner in the intermediate tube region and has a constant diameter in the distal tube region.

  As the material of the position marker 16, it is preferable to use a metal having high radiopacity such as platinum or gold.

4). Structure and Manufacturing Process of Guide Wire Passing Tube 6 One of the characteristic configurations of the present invention is that the guide wire passing tube 6 includes an inner layer tube, and a linear body as a reinforcing material in at least a part of the inner layer tube. A reinforcing layer in which the element wire is wound in a coil shape in only one of the left and right directions, and a resin outer layer covering the inner layer tube and the reinforcing layer.

  Here, in order to show the structure of the guide wire passing tube 6 in more detail, the manufacturing process will be shown.

  First, a metal core wire 19 is prepared as shown in FIG. The metal core wire is wound around a reel 20, and the outer diameter thereof is substantially the same as the inner diameter of the guide wire passing tube to be manufactured. The material is preferably a metal-plated copper wire or a stainless steel wire.

  Subsequently, as shown in FIG. 6, the inner layer tube 21 is formed by extrusion coating on the metal core wire by the extruder 22.

(Inner layer pipe)
As a constituent material of the inner layer tube, for example, fluorine-based polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, ethylene-tetrafluoroethylene copolymer, etc. Examples thereof include resins, polyolefins such as polypropylene, polyethylene, and ethylene-vinyl acetate copolymer, polyesters such as polyamide, polyethylene terephthalate, and polybutylene terephthalate, resins such as polyurethane, polyvinyl chloride, polystyrene resins, and polyimides, and mixtures thereof. However, from the viewpoint of obtaining excellent position-adjustability with a guide wire following property, the finished product exhibits excellent lubricity with respect to the guide wire or the like passing through the inner layer tube, or polytetrafluoroethylene or It is preferably made of a perfluoroalkyl vinyl ether copolymer - tetrafluoroethylene. When polytetrafluoroethylene is used, it is fired after treatment such as drying of the additive.

  It is preferable that the inner layer tube covered with the metal core wire has a sufficient adherence to the metal core wire. Further, in the process of coating the outer tube, the mechanical method (such as rubbing the inner tube surface with sandpaper) and / or the like for the purpose of increasing the adhesion between the inner tube and the outer tube, and / or Concavities and convexities may be formed or surface modified by a chemical method (use of a defluorinating agent such as sodium naphthalene + dimethyl ether) and / or an electric method such as plasma.

  The metal core wire covering the inner layer tube is cut to an appropriate length, and the coating on both ends is peeled off, and then set on the coiling machine 23 as shown in FIG. The coiling machine is a device for winding a wire forming a reinforcing layer on an inner layer tube in a coil shape by holding both ends of a metal core wire covering the inner layer tube and applying a rotational force.

  The end of the wire 24 is fixed by a shrink tube 25 or an adhesive as shown in FIG. 8, and winding is started. The strands are supplied from the strand supply unit 26.

  For the strands, synthetic resin strands or metal strands with high X-ray transmittance are used. It is preferable to use a synthetic resin strand or metal strand having a circular cross section.

(Synthetic resin wire)
As a synthetic resin strand, a sheath made of a molten liquid crystal polymer core 27 and a molten liquid crystal polymer island 28 and a flexible polymer sea 29 as shown in the conceptual cross-sectional view of FIG. It has a structure covering the core. FIG. 9B shows a scanning micrograph of this portion. The molten liquid crystal polymer is made of polyarylate, and the flexible polymer is made of polyethylene naphthalate. Since such a synthetic resin strand has a structure in which the core of the molten liquid crystal polymer is covered with a sheath, the core of the molten liquid crystal polymer does not fibrillate during processing and become fuzzy. A synthetic resin strand having such a structure comprises a die that melts and extrudes the molten liquid crystal polymer corresponding to the core portion, and a mixture of the molten liquid crystal polymer and the flexible polymer that is disposed coaxially and corresponds to the sheath portion. It can be obtained by performing spinning while extruding each polymer from a base that is melted and extruded. The diameter of the synthetic resin strand preferably used is preferably 5 to 50 μm.

  Other synthetic resin strands used in the present invention include, for example, polyethylene terephthalate, polybutylene terephthalate, polyester such as polymethylene terephthalate, polyolefin such as polyethylene and polypropylene, rigid polyvinyl chloride, polyamide, polyimide, polystyrene, Thermoplastic polyurethane, polycarbonate, ABS resin, acrylic resin, polymethyl methacrylate, polyacetal, polyarylate, polyoxymethylene, high tension polyvinyl alcohol, fluororesin, polyvinylidene fluoride, polytetrafluoroethylene, ethylene-vinyl acetate saponified product, polysulfone, Aromatic polymers such as polyethersulfone, polyetherketone, polyphenylene oxide, polyphenylene sulfide, and Kevlar. Such as aramid, a polymer alloy containing any of these, carbon fibers, glass fibers and the like.

(Metal wire)
Examples of the metal strand include stainless steel, C—Mn—Si—PS—Cr—Mo—Ni—Fe—X (X═Au, Os, Pd, Re, Ta, Ir, Ru) alloy, C—Mn—. Si-PS-Cr-Mo-Ni-X (X = Au, Os, Pd, Re, Ta, Ir, Ru) alloy, copper, nickel, titanium, piano wire, Co-Cr alloy, Ni-Ti alloy , Ni—Ti—Co alloy, Ni—Al alloy, Cu—Zn alloy, Cu—Zn—X alloy (for example, X = Be, Si, Sn, Al, Ga), various metals such as amorphous alloys Of these materials, the use of stainless steel is preferred for reasons such as workability, economy, and lack of toxicity. The metal strand is preferably about 5 to 50 μm in diameter.

  These strands may be used alone, or an assembly of strands (for example, a bundle of synthetic resin strands, a bundle of metal strands, a synthetic resin strand and a metal strand) Any of the bundles may be used.

(Winding pitch)
The winding pitch of the strands may be constant as shown in FIG. 10 or may be different. When the intervals are different, it is preferable that the pitch is smaller at the position corresponding to the distal portion of the guide wire passing tube. The winding pitch of the strand is preferably 0.1 to 2.0 mm because it has both flexibility and a reinforcing effect.

  If the wire has been wound, the end of the wire is fixed with an adhesive or the like, and then the wire is cut.

  Subsequently, as shown in FIG. 11, the inner tube and the reinforcing layer are covered with the resin outer layer 30. The resin outer layer 30 is a resin tube having an inner diameter slightly larger than the outer diameter of the inner layer tube around which the reinforcing layer is wound.

  The medical balloon tube of the present invention with improved narrow lesion passing ability is integrated with the guide wire passing tube having the reinforcing material layer and the core wire, and the structure is integrated into the distal portion of the balloon catheter. By providing this, it is possible to obtain a medical balloon tube with high reachability to a lesioned part and high certainty of expansion treatment.

(Resin outer layer)
As the material of the resin tube forming the outer tube, various elastomers such as polyamide elastomer, polyester elastomer, polyurethane elastomer, polystyrene elastomer, fluorine elastomer, silicone rubber, latex rubber, or a combination of two or more of these are used. Is possible.

  Here, the polyamide elastomer is, for example, nylon 6, nylon 64, nylon 66, nylon 610, nylon 612, nylon 46, nylon 9, nylon 11, nylon 12, N-alkoxymethyl modified nylon, hexamethylenediamine-isophthalic acid. Typical block copolymers include polycondensates, various aliphatic or aromatic polyamides such as metaxyloxydiamine-adipic acid polycondensate as hard segments, and polymers such as polyester and polyether as soft segments. In addition, a polymer alloy (polymer blend, graft polymerization, random polymerization, etc.) of the polyamide and a flexible resin, a softened polyamide with a plasticizer or the like, and a concept including a mixture thereof It is.

  The polyester elastomer is typically a block copolymer of a saturated polyester such as polyethylene terephthalate or polybutylene terephthalate and a polyether or polyester. In addition, the polymer alloy or the saturated polyester may be used as a plasticizer. It is a concept that includes a softened material and a mixture thereof.

  As a material suitably used, a polyamide elastomer is preferable from the viewpoint of processability and flexibility. For example, PEBAX manufactured by elf atochem is representative. If the guide wire passing tube and the balloon are made of the same material, they can be strongly and liquid-tightly integrated when they are heat-sealed.

  The resin outer layer may have the same hardness, or the position corresponding to the distal portion of the guide wire passing tube may be more flexible.

  The whole covered with the resin outer layer is further covered with a shrink tube 31 having the property of reducing its diameter by heating. The shrink tube is preferably made of polytetrafluoroethylene or perfluoroethylene-propene copolymer.

  Thereafter, the shrink tube is heated with a heater to a temperature at which the tube contracts, or is heated by applying high-frequency electromagnetic waves, and the inner tube, the reinforcing layer, and the resin outer layer are integrated. After that, the shrink tube is peeled off and the metal core wire is pulled out to obtain a guide wire passing tube.

5. Effect by Embodiment The guide wire passing tube thus obtained is a reinforcing material obtained by winding a wire in a coil shape when it is delivered to a narrow lesion when a medical balloon catheter is configured using the tube. Due to this effect, the force for pushing the balloon catheter is transmitted without causing buckling or kinking easily, and the reachability to the lesioned part and the certainty of the expansion treatment are increased.

6). Hydrophilic coating The outer surface of the medical balloon catheter can be provided with a hydrophilic coating in order to facilitate insertion into a blood vessel or a guide catheter. That is, it is preferable to apply a hydrophilic coating that exhibits lubricity when in contact with blood, such as a base end tube, an intermediate tube, a distal end tube, and an outer surface of a balloon, in contact with blood. The kind of hydrophilic coating is not particularly limited, and hydrophilic polymers such as poly (2-hydroxyethyl methacrylate), polyacrylamide, and polyvinylpyrrolidone can be suitably used, and the coating method is not limited.

FIG. 1 is a schematic perspective view of an over-the-wire type of a general PTCA balloon catheter. FIG. 2 is a schematic perspective view of a high-speed exchange type among general PTCA balloon catheters. FIG. 3 shows an overall configuration diagram of an embodiment of the present invention. FIG. 4 shows a distal portion of a medical balloon catheter as an embodiment of the present invention. FIG. 5 shows a process of winding a metal core wire around a reel. FIG. 6 shows a process of extrusion coating the inner layer tube on the metal core wire. FIG. 7 shows a process of winding a wire in a coil shape by a coiling machine. FIG. 8 shows a process of starting winding of the wire. FIG. 9 shows an outline of the structure of a strand that can be particularly suitably used as a synthetic resin strand. FIG. 10 shows the winding state of the strand. FIG. 11 shows a state in which the inner layer tube and the reinforcing layer are covered with a resin outer layer and further a shrink tube is covered.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Catheter shaft 2 Balloon 3 Hub 4 Guide wire lumen 5 Guide wire port 6 Guide wire passage tube 7 Hub 8 Strain relief 9 Base end tube 10 Balloon 11 Intermediate tube 12 End tube 13 Position marker 14 Core wire 15 Core wire Fixed portion 16 Position marker 17 Guide wire port 18 Balloon expansion lumen 19 Metal core wire 20 Reel 21 Inner layer tube 22 Extruder 23 Coiling machine 24 Wire 25 Shrink tube 26 Wire supply portion 27 Molten liquid crystal polymer core 28 Molten liquid crystal polymer island (sheath)
29 Sea of flexible polymer (sheath)
30 Resin outer layer 31 Shrink tube

Claims (4)

From the base side to the tip side,
A proximal tube (a) constituting a lumen for balloon expansion,
Middle tube (b),
A tip tube (c) having a balloon portion fixed to the distal end; and
A medical balloon catheter having a tip opening at the tip, the balloon portion fixed at the distal end, and a guide wire passage tube (d) covered with the tip tube (c) and the balloon portion. Because
The intermediate tube (b) and the tip tube (c) have a balloon expansion lumen and a core wire,
In the proximal portion of the distal end tube (c), there is a guide wire port that is a proximal end side opening of the guide wire passing tube (d),
The guide wire passing tube (d) includes an inner layer tube, a reinforcing layer in which a linear body is wound around at least a part of the inner layer tube in only one of the left and right directions, and the inner layer tube and the reinforcing layer. A resin outer layer covering
A medical balloon catheter.   The medical balloon catheter according to claim 1, wherein the inner layer tube of the guide wire passage tube (d) is made of a fluororesin.   The medical balloon catheter according to claim 1 or 2, wherein the linear body of the guide wire passing tube (d) is a metal strand or a synthetic resin strand. The resin outer layer of the guide wire passing tube (d) is made of any resin material of polyamide elastomer, nylon, polyester, polyester elastomer, polyurethane elastomer, polyolefin, polyimide, polyimide amide, and polyether imide. Item 4. The medical balloon catheter according to any one of Items 1 to 3.