WO2018008516A1

WO2018008516A1 - Balloon catheter

Info

Publication number: WO2018008516A1
Application number: PCT/JP2017/023962
Authority: WO
Inventors: 匡生佐藤; 荘一郎北; 仁田原; 良二中野; 渡邊　基一; 西出　拓司
Original assignee: 株式会社カネカ
Priority date: 2016-07-04
Filing date: 2017-06-29
Publication date: 2018-01-11

Abstract

A balloon catheter 1 having a shaft 2 and a balloon 10 provided on the outside of the shaft 2. The balloon 10 has a base balloon and a reinforced section 12 arranged linearly or in a mesh-like shape on the outside surface of the base balloon. The reinforced section 12 is formed protruding from the outside surface of the balloon 10 and a drug is held in a section on the outside surface of the balloon 10 that is not the reinforced section 12.

Description

Balloon catheter

The present invention relates to a balloon catheter, and more particularly to a balloon catheter holding a drug.

It is known that stenosis occurs in a blood vessel that is a flow path for blood to circulate in the body, and various diseases occur when blood circulation is delayed. In particular, when a stenosis occurs in a coronary artery that supplies blood to the heart, there is a risk of causing serious diseases such as angina pectoris and myocardial infarction. One method for treating such a stenosis of a blood vessel is an angioplasty (PTA, PTCA, etc.) that expands the stenosis using a balloon catheter. Angioplasty is widely performed because it is a minimally invasive therapy that does not require thoracotomy such as bypass surgery.

By the way, in the case of angioplasty, restenosis may occur in an expanded stenosis, and drug elution with a drug layer on the surface is a treatment method that reduces the frequency of such restenosis (restenosis rate). Treatment using a stent is performed. In addition, drug-eluting balloon catheters in which a drug is held in the balloon portion of the balloon catheter have been proposed (for example, Patent Documents 1 to 4). If a drug-eluting balloon catheter is used, the drug can be transferred to the blood vessel wall by expanding the balloon at the stenosis or lesion, and the occurrence of restenosis can be expected to be suppressed. Advantages of a treatment method using a drug-eluting balloon catheter include that no foreign matter is left in the body, and that small blood vessels into which a stent cannot be inserted can be treated.

However, since the drug held on the balloon surface is in direct contact with blood, blood vessels, etc., the drug elutes or falls off during delivery to the stenosis or lesion (hereinafter sometimes referred to as delivery). By doing so, there is a possibility that a drug necessary for treatment cannot be delivered to a stenosis or a lesion.

US Pat. No. 5,304,121 Japanese National Patent Publication No. 5-505132 Special table 2008-529740 Japanese Patent Laid-Open No. 2015-217260

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a balloon catheter in which a drug is held on the outer surface of the balloon, and the balloon catheter that can suppress the dissolution and dropping of the drug during delivery. It is to provide.

The balloon catheter of the present invention that has solved the above-mentioned problems is a balloon catheter having a shaft and a balloon provided on the outer side of the shaft, and the balloon is formed on the outer surface of the base balloon and the base balloon. And a reinforcing portion arranged in a line or net shape, the reinforcing portion is formed to protrude from the outer surface of the balloon, and the drug is held in a portion other than the reinforcing portion on the outer surface of the balloon .

The reinforcing part preferably has a height of 0.1 mm or more and 0.5 mm or less. It is preferable that a portion other than the reinforcing portion is formed on the outer surface of the balloon in a size that does not include a circle having a diameter of 1.5 mm. In addition, the circle described here is a figure temporarily drawn so that the diameter of the inscribed circle in contact with the reinforcing portion is maximized, and is for expressing the size of a portion other than the reinforcing portion. It is preferable that the reinforcement part is arrange | positioned at the mesh shape containing the polygon more than a pentagon.

It is preferable that portions other than the reinforcing portion on the outer surface of the balloon are formed so as to rise outward in the radial direction of the balloon when a pressure of 0.51 MPa (5 atm) is applied. The portions other than the reinforcing portion on the outer surface of the balloon may be formed so as to rise outward in the radial direction of the balloon from the reinforcing portion when a pressure of 0.51 MPa (5 atm) is applied.

The portion other than the reinforcing portion on the outer surface of the balloon may be formed so as to rise outward in the balloon radial direction when a pressure of 2.03 MPa (20 atm) is applied. The portion other than the reinforcing portion on the outer surface of the balloon may be formed so as to rise outward in the radial direction of the balloon from the reinforcing portion when a pressure of 2.03 MPa (20 atm) is applied.

It is preferable that at least a part of the reinforcing portion is provided so as to extend in the axial direction of the balloon. A part of the reinforcing part may be provided so as to extend in the axial direction of the balloon, and the other part may be provided so as to extend spirally in the circumferential direction of the balloon.

The balloon has an axial length L2 and an outer diameter D2 when 0.20 MPa (2 atm) is applied, and the axial length of the straight tube when 0.51 MPa (5 atm) is applied. When L is L5 and the outer diameter is D5, the axial length change rate (L5-L2) / L2 is larger than the outer diameter change rate (D5-D2) / D2. Is also preferable. The balloon has an axial length L2 and an outer diameter D2 at 0.20 MPa (2 atm) pressurization, and an axial length of the straight pipe portion at 2.03 MPa (20 atm) pressurization. When the length is L20 and the outer diameter is D20, the axial length change rate (L20-L2) / L2 is larger than the outer diameter change rate (D20-D2) / D2. May be.

The reinforcing part is preferably formed by bonding a fiber material to the outer surface of the base balloon.

The drug is preferably an antiproliferative agent or an immunosuppressive agent.

According to the balloon catheter of the present invention, it is possible to suppress elution and dropout of the drug during delivery by holding the drug in a portion other than the reinforcing portion formed to protrude from the outer surface of the balloon.

1 represents a plan view of a balloon catheter. 2A is a cross-sectional view taken along the line AA of the balloon catheter shown in FIG. 1, and FIG. 2B is a cross-sectional view taken along the line BB of the balloon catheter shown in FIG. The top view of a balloon is represented as an example of the balloon with which the balloon catheter shown in FIG. 1 is equipped. The top view of the other example of a balloon is represented. The top view of the other example of a balloon is represented. The top view of the other example of a balloon is represented. The top view of the other example of a balloon is represented. The example of sectional drawing of the balloon of a non-pressurization state and a pressurization state is represented. The example of the balloon sectional drawing of the state which expanded the balloon in the axial direction and the state shrunk | reduced is represented.

The present invention relates to a balloon catheter in which a drug is held on the balloon surface. Specifically, a reinforcing portion is provided in a linear or net shape on the outer surface of the base balloon, and the reinforcing portion protrudes from the outer surface of the balloon. The present invention relates to a balloon catheter having a provided balloon and having a drug held in a portion other than the reinforcing portion on the outer surface of the balloon. According to the balloon catheter of the present invention, the drug can be prevented from being eluted or dropped during delivery by holding the drug in a portion other than the reinforcing portion on the outer surface of the balloon.

Hereinafter, the balloon catheter of the present invention will be described in detail based on the following embodiment, but the present invention is not limited by the following embodiment as a matter of course, and is appropriately within a range that can meet the purpose described above and below. Of course, it is possible to carry out with modifications, and these are all included in the technical scope of the present invention. In addition, in each drawing, although hatching, a member code | symbol, etc. may be abbreviate | omitted for convenience, in this case, a description and another drawing shall be referred. In addition, the dimensions of the various members in the drawings are given priority to contribute to the understanding of the characteristics of the present invention, and may be different from the actual dimensions.

The overall configuration of the balloon catheter will be described with reference to FIG. 1 and FIG. FIG. 1 shows a plan view of a balloon catheter, and FIGS. 2 (a) and 2 (b) show an AA sectional view and a BB sectional view of the balloon catheter shown in FIG. 1, respectively. Yes. FIG. 1 shows a configuration example of an over-the-wire type balloon catheter in which a wire is inserted from the distal side to the proximal side of the shaft.

The balloon catheter 1 has a shaft 2 and a balloon 10 provided outside the shaft 2. The balloon catheter 1 has a proximal side and a distal side, a balloon 10 is provided on the distal side of the shaft 2, and a hub 5 is provided on the proximal side of the shaft 2. In the present invention, the proximal side of the balloon catheter refers to the direction of the proximal side of the user (operator) with respect to the extending direction of the balloon catheter (particularly the shaft), and the distal side is opposite to the proximal side. The direction (that is, the direction on the treatment target side) is indicated. A direction from the proximal side to the distal side of the balloon is referred to as an axial direction.

The balloon catheter 1 is configured such that a pressure fluid is supplied from the hub 5 to the inside of the balloon 10 through the shaft 2, and the expansion and contraction of the balloon 10 can be controlled using an indeflator.

The shaft 2 is usually provided with a flow path for pressure fluid and a wire insertion path for guiding the progress of the shaft 2 inside. For example, the shaft 2 includes an inner tube 3 and an outer tube 4, and the inner tube 3 functions as a wire insertion path, and a space between the inner tube 3 and the outer tube 4 functions as a flow path for pressure fluid. In this case, on the distal side of the shaft 2, the inner tube 3 extends from the distal end of the outer tube 4 and penetrates the balloon 10 in the axial direction, and the distal side of the balloon 10 is joined to the inner tube 3. The proximal side is configured to be joined to the outer tube 4.

The hub 5 has a fluid injection part 6 that communicates with the flow path of the pressure fluid, and a treatment part 7 that communicates with the wire insertion path. In addition to inserting the wire, the treatment unit 7 can function as an injection port for a medicine or the like, or a suction port for a fluid or the like in a body cavity.

The bonding of the balloon 10, the shaft 2 (the inner tube 3, the outer tube 4) and the hub 5 can be performed using a conventionally known bonding means such as an adhesive or heat welding. In addition, an X-ray opaque marker may be arranged at the portion of the shaft 2 where the balloon 10 is located in order to make it possible to confirm the position of the balloon 10 under X-ray fluoroscopy.

The present invention can also be applied to a rapid exchange type balloon catheter in which a wire is inserted halfway from the distal side to the proximal side of the shaft. In this case, the wire insertion path may be provided in a part of the shaft including the distal side of the shaft, and the treatment portion may not be provided in the hub. FIGS. 1 and 2 show a general balloon catheter in which blood does not pass through the shaft. However, the present invention does not expand the balloon for a long time so that the medicine held in the balloon is transferred to the inner wall of the blood vessel. Can be applied to a perfusion-type balloon catheter having a perfusion lumen that can pass through a balloon and move blood between a proximal side and a distal side of the balloon.

FIG. 3 shows an enlarged view of the balloon provided in the balloon catheter shown in FIG. The balloon provided in the balloon catheter is not limited to the balloon shown in FIG.

The balloon 10 has a base balloon 11 and a reinforcing portion 12 arranged in a linear or net shape on the outer surface of the base balloon 11, and the reinforcing portion 12 is formed to protrude from the outer surface of the base balloon 11. The base balloon 11 defines the basic shape of the balloon 10 and is formed in a bag shape having openings on the proximal side and the distal side. The reinforcing portion 12 is provided on the outer surface of the base balloon 11 in a linear or net pattern, and the reinforcing portion 12 is fixed to the outer surface of the base balloon 11 in this pattern. By providing the reinforcing portion 12 on the outer surface of the base balloon 11, it is possible to increase the strength of the balloon 10 and to suppress overexpansion during pressurization. It is also possible to give the reinforcing part 12 a scoring function and to expand the stenosis part calcified in angioplasty by cracking.

As shown in FIG. 3, the balloon 10 has a cylindrical straight tube portion 14, a proximal taper portion 15 connected to the proximal side thereof, and a distal taper portion 16 connected to the distal side. Preferably, the proximal taper portion 15 and the distal taper portion 16 are formed so as to be reduced in diameter as they move away from the straight tube portion 14. A cylindrical proximal sleeve 17 is connected to the proximal side of the proximal tapered portion 15, and a cylindrical distal sleeve 18 is connected to the distal side of the distal tapered portion 16. In the catheter shown in FIG. 1, the proximal sleeve 17 is joined to the outer tube 4 of the shaft 2, and the distal sleeve 18 is joined to the inner tube 3 of the shaft 2. What is necessary is just to set suitably the outer diameter of the straight tube | pipe part 14, the length of an axial direction, the taper angle of the

taper parts

15 and 16, and the length of an axial direction according to the desired function of the balloon 10. FIG. In addition, the balloon 10 can be formed in a substantially cylindrical shape by setting the taper angle of the tapered

portions

15 and 16 to 90 ° with respect to the axial direction. The balloon 10 is configured such that the distal tapered portion 16 swells from the proximal tapered portion 15 through the straight tube portion 14 when a pressure fluid is supplied, and in the present invention, the inflatable portion. Is considered a balloon.

The base balloon can be manufactured, for example, by molding a resin. For example, the base balloon can be manufactured by placing a resin tube extruded by extrusion molding in a mold and biaxially stretching blow molding. The base balloon can be formed in an arbitrary shape depending on the shape of the mold. In addition, the base balloon can be manufactured by a known molding method such as dip molding, injection molding, and compression molding. The base balloon may be composed of a plurality of resin layers, or may have a layer other than the resin layer.

Examples of the resin constituting the base balloon include polyamide resins, polyester resins, polyurethane resins, polyolefin resins, vinyl chloride resins, silicone resins, and natural rubber. These may use only 1 type and may use 2 or more types together. Among these, polyamide resins, polyester resins, and polyurethane resins are preferably used. For these resins, it is preferable to use an elastomer resin from the viewpoint of thinning the balloon and flexibility. For example, nylon 12 and nylon 11 and the like are suitable materials for the base balloon among polyamide resins, and nylon 12 is preferably used because it can be molded relatively easily when blow molding. Further, polyamide elastomers such as polyether ester amide elastomers and polyamide ether elastomers are preferably used from the viewpoint of thinning the balloon and flexibility. Of these, polyether ester amide elastomers are preferably used because they have high yield strength and good dimensional stability of the balloon.

The dimensions of the base balloon may be appropriately set according to the size of the treatment site. For example, when the treatment site is a blood vessel, the axial length is preferably 5 mm to 300 mm and the outer diameter is preferably 1 mm to 12 mm. When the treatment site is a digestive tract such as a duodenal papilla, the axial length is preferred. Is preferably 10 mm to 100 mm, and the outer diameter is preferably 3 mm to 30 mm.

The reinforcing portion 12 is provided on the outer surface of the base balloon 11 in a linear or net pattern. The reinforcing portion 12 is formed so as to protrude on the outer surface of the balloon 10, that is, provided on the outer surface of the balloon 10 so as to protrude outward in the balloon radial direction. The reinforcing portion 12 is provided as a layer partially disposed on the outer surface of the base balloon 11. A non-reinforcing portion 13 is formed in a portion other than the reinforcing portion 12 on the outer surface of the balloon 10. Accordingly, the reinforcing portion 12 is formed so as to protrude from the non-reinforcing portion 13 on the outer surface of the balloon 10, and the non-reinforcing portion 13 is formed to be recessed with respect to the reinforcing portion 12. In the balloon 10, the reinforcing portion 12 is formed thicker than the non-reinforcing portion 13.

As the reinforcing part 12 provided in a linear pattern, a mode in which the linear reinforcing part 12 is arranged so as to extend in the axial direction of the balloon (see FIG. 4A), the linear reinforcing part 12 includes A mode (see FIG. 4B) extending in the circumferential direction of the balloon and arranged in a ring shape, and a mode in which a linear reinforcing portion is arranged in a spiral shape (coil shape) on the outer surface of the balloon (FIG. 4 ( see c)). In this case, a plurality of linear reinforcing portions may be provided, but the reinforcing portions are arranged so as not to cross each other.

The reinforcing part provided in the net-like pattern is not particularly limited as long as the linear reinforcing parts are arranged so as to cross each other, for example, formed by combining each aspect of the linear pattern described above can do. In the portion where the linear reinforcing portions intersect, the linear reinforcing portions may simply intersect each other (overlapping structure) or may form a knitted structure (braided structure). FIG. 3 shows a mode in which the reinforcing portions are arranged in a net pattern in which a pattern extending linearly in the axial direction and a right-handed and left-handed spiral pattern are combined. FIG. 5A shows a mode in which the reinforcing portions are arranged in a net-like pattern in which right-handed and left-handed spiral patterns are combined. Moreover, you may provide a reinforcement part with lattice-like patterns, such as a triangular lattice and a hexagonal lattice, as a net-like pattern. FIG. 5B shows a mode in which the reinforcing portions are arranged in a hexagonal lattice pattern.

The height and line width of the reinforcing part may be appropriately set according to the desired performance of the balloon. The reinforcing portions may all be provided at the same height, or may be provided so as to have different height portions. Moreover, all the reinforcement parts may be provided with the same line width, and may be provided so that it may have a part with a different line width. For example, the height of the reinforcing portion is preferably 0.01 mm or more, more preferably 0.1 mm or more, and preferably 0.5 mm or less. The height of the reinforcing part means a height protruding from the outer surface of the balloon, and can be obtained by measuring the height from the non-reinforcing part. Moreover, when forming a reinforcement part from a fiber material so that it may mention later, the thickness of a fiber material may be made into the height of a reinforcement part. The line width of the reinforcing portion is, for example, preferably 0.02 mm or more, more preferably 0.1 mm or more, and preferably 0.3 mm or less. The line width of the reinforcing portion is obtained by measuring, for example, the half-value width of the height of the reinforcing portion (the width of the portion where the height of the reinforcing portion is half), or the reinforcing portion is formed from a fiber material as described later. When doing, it is good also considering the width | variety (thickness) of a fiber material as the line | wire width of a reinforcement part. The height and line width of the reinforcing part can be obtained by measuring the cut section of the balloon.

The proportion of the reinforcing portion on the outer surface of the balloon (the proportion of the area occupied by the reinforcing portion on the outer surface of the balloon) may be appropriately set according to the desired performance of the balloon. For example, the area ratio of the reinforcing portion on the outer surface of the straight tube portion of the balloon is preferably 20% or more, more preferably 30% or more, and preferably 80% or less, more preferably 60% or less. The area ratio of the reinforced part on the outer surface of the balloon is defined as the area where the height of the reinforced part is halved as the boundary between the reinforced part and the non-reinforced part, and the higher part is regarded as the reinforced part. Can be requested. Moreover, when forming a reinforcement part from a fiber material so that it may mention later, you may obtain | require the installation area (projection area to the base balloon surface) of a fiber material as an area of a reinforcement part.

The height and line width of the reinforcing portion and the area ratio of the reinforcing portion described above can be obtained by cutting or expanding the balloon and measuring the balloon in a non-pressurized state. Various values to be described later also mean values in a non-pressurized state of the balloon unless otherwise specified.

補強 The reinforcing part may be made of the same material as the base balloon or may be made of a different material. The reinforcing part is preferably made of a material that is stronger and harder to stretch than the base balloon. By configuring the reinforcing part in this way, the reinforcing part can have a scoring function, or the dimensional stability of the balloon. Can be increased.

The reinforcing portion can be formed, for example, by bonding a fiber material to the outer surface of the base balloon. The fiber material may be monofilament or multifilament. From the viewpoint of increasing the strength of the balloon, the fiber material preferably has a higher strength and is less likely to stretch (has a higher elastic modulus) than the base balloon, and preferably has a higher tensile strength. Examples of such a fiber material include polyarylate fiber, aramid fiber, ultrahigh molecular weight polyethylene fiber, PBO fiber, and carbon fiber.

For example, in the case of the balloon shown in FIG. 3, a plurality of fiber materials 21 parallel to the axial direction of the base balloon and arranged at intervals in the circumferential direction, and a plurality of spirally

wound fiber materials

22, 23 are knitted. The reinforcing portion can be formed by superimposing or knitting them as they are without knitting. When the fiber materials are overlapped without being knitted, the fiber material 21, the fiber material 22 (23), and the fiber material 23 (22) may be overlapped sequentially from the surface over the entire length of the base balloon 11 in the axial direction. The fiber material 22 (23), the fiber material 21, and the fiber material 23 (22) may be overlapped, or the fiber material 22 (23), the fiber material 23 (22), and the fiber material 21 may be overlapped. In the case of knitting each fiber material, the

fiber materials

21, 22, and 23 may be structured so as to be knitted by regularly replacing the outer side and the inner side in the balloon radial direction. The winding direction of the spirally wound fiber material 22 is opposite to that of the spirally wound fiber material 23. The

fiber materials

21, 22, and 23 may be wound uniformly or may be wound non-uniformly. For example, by forming a plurality of fibers together to form the

fiber materials

21, 22, and 23, when a large number of fibers are arranged in the circumferential direction, they can be easily manufactured without using a complicated device. Is possible.

As a method of joining the fiber material to the base balloon, a method in which an adhesive is applied from the outside of the fiber material in a state where the fiber material is disposed on the outer surface of the base balloon, and an adhesive is applied to the base balloon and / or the fiber material. Thereafter, a method of arranging a fiber material on the outer surface of the base balloon, a method of joining the fiber material to the base balloon by heat welding, and the like can be mentioned. A resin can also be used as the adhesive.

The number of fiber materials may be set as appropriate in consideration of the size of the base balloon, the thickness of the fiber material (height and line width of the reinforcing portion), the strength of the balloon, the amount of drug retained, and the like. For example, a plurality of fiber materials extending in the axial direction (reinforcing portions extending linearly in the axial direction) are preferably arranged at intervals in the circumferential direction, and the number of fibers arranged in the circumferential direction at this time is 3 to 30 It is preferable that In addition, the number of spirally wound fiber materials (reinforcing portions extending in a spiral shape) is preferably 3 to 30, and the winding angle at this time ranges from 50 ° to 80 ° with respect to the axial direction. It is preferable to set by.

The drug is held in the balloon other than the reinforcement part on the outer surface of the balloon, that is, at least the non-reinforcement part. Since the non-reinforcing part of the balloon is formed to be recessed with respect to the reinforced part, the elution and dropping of the drug during delivery can be suppressed by holding the drug here. When expanding a balloon by pressurizing it, the reinforcing part bites into the inner wall of the stenosis or the lesioned part so that the drug of the non-reinforcing part is pressed against the inner wall or the like, or the interval between adjacent reinforcing parts is widened. Alternatively, the non-reinforcing part is pressed from the inside of the balloon, so that the medicine held in the non-reinforcing part can be efficiently transferred to the stenosis part or the lesion part. If the reinforced part has a scoring function, the reinforced part can also be expanded by cracking the stenosis or lesion, so the drug is usually delivered to the back of the stenosis or lesion where it is difficult to deliver the drug. It can also be delivered.

The drug retained in the balloon is not particularly limited as long as it is a pharmacologically active substance, and examples thereof include pharmaceutically acceptable drugs such as gene therapy drugs, non-gene therapy drugs, small molecules, and cells. In particular, when a balloon catheter is used for the purpose of suppressing vascular restenosis after treatment in angioplasty, an anti-restenosis agent such as an antiproliferative agent or an immunosuppressive agent can be preferably used as the drug. For example, drugs such as paclitaxel, sirolimus (rapamycin), everolimus, and zotarolimus can be used. These drugs may be used alone or in combination of two or more.

The drug may be held in the non-reinforced portion as a drug layer, or may be held in the non-reinforced portion in the form of a microcapsule or the like. The drug may contain, together with the pharmacologically active substance, an auxiliary agent for improving the dispersibility, solubility, migration to the blood vessel wall, and storage stability of the drug. As auxiliary agents, stabilizers, binders, disintegrants, moisture-proofing agents, preservatives, dissolution aids and the like are used. Specifically, lactose, sucrose, maltose, dextrin, xylitol, erythritol, mannitol, ethylenediamine, Examples thereof include potassium iodide, urea, polysorbate, dibutylhydroxytoluene, sodium pyrosulfite, ascorbic acid, tocopherol, benzoic acid, and paraoxybenzoic acid esters.

The drug may be held on the balloon in a state protected by the coating layer, which further suppresses the dissolution and dropping of the drug during delivery. The coating layer is preferably a water-soluble polymer from the viewpoint of preventing the initial burst of the drug, for example, carboxymethyl cellulose, hydroxypropyl cellulose, methyl cellulose, hydroxyethyl cellulose, polyvinyl alcohol, alginic acid, pectin, gum arabic, gellan gum, gua gum Xanthan gum, carrageenan, gelatin and the like.

In order to enhance the adhesion of the drug or coating layer to the balloon surface, the outer surface of the balloon may be subjected to a surface treatment. Examples of the surface treatment include plasma treatment, laser treatment, ion treatment, ozone treatment, discharge treatment, and primer treatment.

The height of the reinforcing part is preferably 0.1 mm or more, and more preferably 0.2 mm or more, from the viewpoint of suppressing elution and dropping of the drug during delivery. In addition, by forming the reinforcing part in this way, a scoring function by the reinforcing part can also be expected. Can be delivered. On the other hand, if the height of the reinforcing portion is too high, the drug tends to remain on the outer surface of the balloon when the balloon is expanded, or the blood vessel or the like may be damaged more than necessary. The thickness is preferably 0.5 mm or less. The height of the reinforcing part means the maximum height of the reinforcing part, and the balloon may be provided with a reinforcing part having a lower height.

On the outer surface of the balloon, a portion other than the reinforcing portion has a diameter of 1.5 mm (the diameter is more preferably 1.3 mm, and more preferably 1.1 mm) from the viewpoint of suppressing elution and dropping of the drug during delivery. It is preferable that it is formed in a size that does not include a circle. On the other hand, from the viewpoint of securing the amount of drug retained, the outer surface of the balloon has a circular shape with a diameter of 0.5 mm (the diameter is more preferably 0.8 mm, more preferably 1.0 mm) on the outer surface. It is preferable that it is formed in the size to include. By forming the balloon in this manner, when the balloon is pressurized and expanded, the interval between adjacent reinforcing portions is widened, or the non-reinforcing portion is easily pressed from the inside of the balloon, and the drug is easily released. . For example, in the balloons shown in FIGS. 4 (a) to 4 (c) and FIGS. 5 (a) to 5 (b), the diameter of the inscribed circle 19 in contact with a plurality of adjacent reinforcing portions 12 is less than 1.5 mm. Is preferably 0.5 mm or more. The inscribed circle 19 is defined so as to have the largest diameter at a portion surrounded by the reinforcing portion 12 or a portion sandwiched therebetween.

Although the specific arrangement mode of the reinforcing portion is not particularly limited, it is preferable that the reinforcing portion has a portion extending in the circumferential direction in order to suppress elution and dropping of the drug due to rubbing in the axial direction of the balloon during delivery. . This is because when the balloon catheter is delivered to a stenosis or a lesion, rubbing between the balloon surface and the inner wall of the guiding catheter, blood vessel or the like is likely to occur in the axial direction of the balloon surface. On the other hand, when a balloon catheter is delivered to a stenosis or lesion, when passing through a highly bent portion, the balloon often passes while rotating. In that case, the balloon surface, guiding catheter, blood vessel, etc. Rubbing with the inner wall tends to occur in the circumferential direction of the balloon surface. From such a viewpoint, it is preferable that the reinforcing portion has a portion extending in the axial direction in order to suppress elution and dropping of the drug due to rubbing in the circumferential direction. Furthermore, in blood vessels such as coronary arteries, after passing through the inside of a long guiding catheter bent at the tip, it is delivered to a stenosis or lesion through a thin and highly bent blood vessel. Both axial and radial rubbing between the surface and the inner wall of the guiding catheter, blood vessel or the like is likely to occur. Therefore, in order to suppress elution and dropping of the drug due to such rubbing, it is preferable that the reinforcing portion is provided in a net-like pattern. That is, the drug is held on the outer surface of the balloon surrounded by the reinforcing portion, so that elution and dropping of the drug under various situations can be suppressed. In this case, portions other than the reinforcing portion (corresponding to FIG. 3 and FIG. 5 (a) ~ unreinforced section 13, (b)) is preferably provided in an area of 8.0 mm ² or less, 7.5 mm ² following More preferably, it is provided in an area. On the other hand, from the viewpoint of securing the drug holding amount, a portion other than the reinforcing portion is preferably provided in 0.1 mm ² or more areas, 0.4 mm ² or more is more preferable. By forming the balloon in this way, when the balloon is pressurized and expanded, the medicine held in the portion other than the reinforcing portion is easily released. In addition, the area of parts other than the reinforcement part demonstrated here means the area of one part other than a reinforcement part.

When the reinforcing portion is provided in a net pattern, the reinforcing portion is preferably arranged in a net shape including a pentagon or more polygon. For example, in the balloon shown in FIG. 5 (b), the reinforcing portions are arranged in a hexagonal lattice network, and in the balloon shown in FIG. 3, the reinforcing portions are arranged in a mesh shape including a hexagon in part. . If the reinforcing portion is provided in this way, when the balloon is expanded while suppressing the elution and dropping of the drug due to axial and radial rubbing between the balloon surface and the inner wall of the guiding catheter or blood vessel during delivery, Further, the drug held near the mesh-like intersection (nodal point) on the outer surface of the balloon is less likely to remain in the balloon, and more drug can be easily transferred to the stenosis or lesion.

The size and shape of the portion other than the reinforcing portion on the outer surface of the balloon described above are preferably determined with respect to the reinforcing portion having a height of 0.1 mm to 0.5 mm. That is, it is preferable that a portion other than the reinforcing portion having a height of 0.1 mm or more and 0.5 mm or less is formed on the outer surface of the balloon in a size that does not include a circle having a diameter of 1.5 mm. It is preferable to be formed in a size including a 0.5 mm circle. When the reinforcing part having a height of 0.1 mm or more and 0.5 mm or less is provided in a net-like pattern, the part other than the reinforcing part is preferably provided with an area of 8.0 mm ² or less, and 0.1 mm ² It is preferable to provide with the above area. Moreover, it is also preferable that the reinforcement part whose height is 0.1 mm or more and 0.5 mm or less is arranged in a net shape including a pentagon or more polygon. The preferred range of the height of the reinforcing portion and the preferred range of the size of the portion other than the reinforcing portion are as described above.

The balloon may be provided with a main reinforcing portion having a height of 0.1 mm to 0.5 mm and an auxiliary reinforcing portion having a height of 0.01 mm to less than 0.1 mm as the reinforcing portion. In this case, the drug is preferably held in a portion other than the main reinforcing portion on the outer surface of the balloon, and the drug may be held in the auxiliary reinforcing portion. The main reinforcing portion functions to suppress the elution and dropout of the drug during delivery, and the pressure resistance and shape retention of the balloon can be enhanced by the auxiliary reinforcing portion. For this reason, it becomes easier to suppress overexpansion during balloon pressurization, and for example, even for a calcified stenosis, the stenosis is expanded and the drug held in the balloon is easily delivered to the back of the stenosis. The height of the auxiliary reinforcing portion is more preferably 0.02 mm or more, and more preferably 0.08 mm or less.

6 and 7 show examples of balloons provided with a main reinforcing portion and an auxiliary reinforcing portion as reinforcing portions. The balloon shown in FIG. 6 is the same as the balloon shown in FIG. 3 except that the reinforcing portion 12 extending in the axial direction of the balloon is provided as the main reinforcing portion 12A, and the reinforcing portion 12 extending spirally in the circumferential direction of the balloon. Is provided as an auxiliary reinforcing portion 12B. The balloon shown in FIG. 7 is provided with a reinforcing portion 12 extending in a spiral shape in one direction as a main reinforcing portion 12A among the reinforcing portions 12 extending spirally in one direction and the other direction in the balloon circumferential direction. The reinforcing portion 12 extending in a spiral shape in the other direction is provided as the auxiliary reinforcing portion 12B.

When the main reinforcing portion and the auxiliary reinforcing portion are provided on the outer surface of the balloon, the outer surface of the balloon has a diameter of 1.5 mm (the diameter is more preferably 1.3 mm, more preferably 1.1 mm). It is preferable that it is formed in a size that does not include a circle of (more preferably). Further, the portion other than the main reinforcing portion is preferably formed in a size including a circle having a diameter of 0.5 mm (the diameter is more preferably 0.8 mm, and further preferably 1.0 mm). In the balloon shown in FIGS. 6 and 7, in the straight tube portion of the balloon, the distance between adjacent main reinforcing portions 12A is preferably less than 1.5 mm, and more preferably 0.5 mm or more. By providing the main reinforcing portion 12A as described above, the portion other than the main reinforcing portion does not include a circle having a diameter of 1.5 mm, and is formed to have a size including a circle having a diameter of 0.5 mm.

When the main reinforcing portion is provided in a net-like pattern, the portion other than the main reinforcing portion is preferably provided with an area of 8.0 mm ² or less, and an area of 0.1 mm ² or more (the area is 0.4 mm ^2). The above is more preferable). Moreover, it is also preferable that the main reinforcement part is arrange | positioned at the mesh shape containing the polygon more than a pentagon.

On the other hand, the installation mode of the auxiliary reinforcing portion is not particularly limited, and may be provided at a higher density than the main reinforcing portion, may be provided at a lower density, or may be provided at a similar density. From the viewpoint of securing the amount of drug retained in the balloon and improving the shape retention of the balloon, the auxiliary reinforcing portion is preferably provided in a larger area ratio than the main reinforcing portion.

From the viewpoint of suppressing overexpansion during balloon pressurization and improving shape retention, the reinforcing portion is preferably provided at an area ratio of 20% or more in the straight tube portion of the balloon, and at an area ratio of 30% or more. More preferably, it is provided. When the reinforcing part is composed of the main reinforcing part and the auxiliary reinforcing part, the area ratio of the main reinforcing part and the auxiliary reinforcing part is preferably within such a range. On the other hand, from the viewpoint of securing the amount of drug retained in the balloon, a relatively high reinforcing portion having a height of 0.1 mm or more and 0.5 mm or less is provided at an area ratio of 80% or less in the straight tube portion of the balloon. It is preferably 60% or less.

Regarding the size of the portion other than the reinforcing portion described above, the portion other than the reinforcing portion having a specific height, and the size of the portion other than the main reinforcing portion, it is not necessary that all of these portions are provided in the sizes described above. However, among these portions provided in the straight pipe portion, the portion provided in the size described above is 50% or more (more preferably 60% or more, and further preferably 70% or more It is provided to occupy an area of In the balloon, the drug may be held in the reinforcing portion. However, from the viewpoint of suppressing the dissolution and dropping of the drug during delivery, it is preferable that the amount of the drug held in the reinforcing portion is small. It is preferable that the amount of drug held by the reinforcing portion or the main reinforcing portion of 1 mm or more and 0.5 mm or less is small. For example, it is preferable that the thickness of the drug layer provided in the reinforcing part or the main reinforcing part having a height of 0.1 mm or more and 0.5 mm or less is half or less than the thickness of the drug layer provided in the other part. .

It is preferable that the portions other than the reinforcing portion on the outer surface of the balloon are formed so as to rise outward in the radial direction of the balloon when the balloon is pressurized. By forming the balloon in this manner, the reinforcing part bites into the blood vessel wall in the initial stage of expansion, and the scoring function is exerted. In the latter half of the expansion, the drug held in the part other than the reinforcing part on the outer surface of the balloon is easily released. The drug can be effectively transferred to a stenosis part or a lesion part. This will be described with reference to FIG.

FIG. 8 shows a schematic sectional view of a balloon. 8A shows a balloon cross-sectional view in a non-pressurized state, and FIGS. 8B and 8C show a balloon cross-sectional view in a pressurized state. 8A to 8C, the lower side of the drawing represents the inner side in the balloon radial direction, and the upper side represents the outer side in the balloon radial direction. A reinforcing portion 12 is provided on the outer surface of the base balloon 11, and in a non-pressurized state as shown in FIG. 8A, the reinforcing portion 12 is formed so as to protrude from the outer surface of the balloon. The non-reinforcing portion 13 in FIG. 8 is formed to be recessed with respect to the reinforcing portion 12. And as shown in FIG.8 (b) and FIG.8 (c), when pressurizing a balloon, when the non-reinforcement part 13 is formed so that it may swell outward in a balloon radial direction, a non-reinforcement part The drug layer cannot follow the rising movement of 13, and it is possible to intentionally crack or crack the drug layer, and the drug held in the non-reinforcing part 13 is transferred to the stenosis or lesion. It becomes easy. In particular, as shown in FIG. 8C, when the non-reinforcing portion 13 is formed so as to swell outward in the radial direction of the balloon from the reinforcing portion 12 when the balloon is pressurized, the balloon is expanded. Since the crack generated at the time can be increased and the area where the non-reinforcing part 13 touches the blood vessel wall can be increased, the drug can be more easily transferred to the stenosis part or the lesion part. In the balloon catheter of the present invention, the drug is held in a portion other than the balloon reinforcement, but the drug is not shown in FIG.

It may be set as appropriate according to the use of the balloon catheter as to how much pressure other than the reinforcing portion on the outer surface of the balloon is formed so as to swell outward in the radial direction of the balloon. In the case of a semi-compliant type balloon in which the balloon diameter expands following the expansion pressure of the balloon, since it is used at a relatively low expansion pressure, the outer surface of the balloon is pressurized at 0.51 MPa (5 atm), for example. It is preferable that portions other than the reinforcing portion are formed so as to rise outward in the balloon radial direction. In the case of a semi-compliant balloon, the base balloon can be a flexible and thin balloon, and can exhibit excellent followability to blood vessels and the like, and the ability to pass through stenosis and lesions. On the other hand, in the case of a non-compliant type balloon in which the balloon diameter hardly increases even when the balloon is pressurized above a certain pressure, since it is used at a relatively high expansion pressure, for example, at a pressure of 2.03 MPa (20 atm), It is preferable that a portion other than the reinforcing portion on the outer surface of the balloon is formed so as to rise outward in the balloon radial direction. In the case of a non-compliant balloon, the stenosis or lesion can be expanded with a high expansion pressure, effectively expanding the hard stenosis or lesion, and usually difficult to deliver the drug. It will be possible to deliver drugs to the back. The pressure at the time of pressurization corresponds to the value of a pressure gauge provided in an indeflator which is a device used at the time of balloon expansion.

The extent of protrusion of the portion other than the reinforced portion of the outer surface of the balloon, as shown in FIG. 8 (b), the height H _b of the height H _a and the portion other than the reinforced portion of the reinforcement portion of the outer surface of the balloon Can be expressed as an index. Basically, the height H _a of the reinforcing portion on the outer surface of the balloon is maintained at a substantially constant height regardless of the expansion pressure, and the height H _b of the portion other than the reinforcing portion increases as the expansion pressure increases. .

For example, in the case of a semi-compliant type balloon, the degree of bulging of the portion other than the reinforcing portion is the difference between the height H _a of the reinforcing portion and the height H _b of the portion other than the reinforcing portion (ΔH = H _a −H _b ). It may be set as an index, and it is preferable that ΔH ₅ when 0.51 MPa ( ₅ atm) is applied is smaller than ΔH ₂ when 0.20 MPa (2 atm) is applied. The portion other than the reinforcing portion may be formed so as to rise to the height of the reinforcing portion when 0.51 MPa (5 atm) is applied, and 0.51 MPa (5 atm) is applied as shown in FIG. The portion other than the reinforcing portion may be formed so as to rise outward in the radial direction of the balloon with respect to the reinforcing portion when the pressure is applied.

In the case of a non-compliant type balloon, the degree of bulging of the portion other than the reinforcing portion is the difference between the height H _a of the reinforcing portion and the height H _b of the portion other than the reinforcing portion (ΔH = H _a −H _b ). It may be set as an index, and it is preferable that ΔH _{20 at the time of} pressurization of 2.03 MPa (20 atm) is smaller than ΔH _{2 at the time of} pressurization of 0.20 MPa (2 atm). The portion other than the reinforcing portion may be formed so as to rise to the height of the reinforcing portion when 2.03 MPa (20 atm) is applied. As shown in FIG. 8 (c), 2.03 MPa (20 atm) is applied. The portion other than the reinforcing portion may be formed so as to rise outward in the radial direction of the balloon with respect to the reinforcing portion when the pressure is applied.

The height H _b of the height H _a and the portion other than the reinforced portion of the reinforcement portion of the balloon under pressure, can be measured using a surface roughness meter. Obtain a three-dimensional image of the outer surface of the balloon using a surface roughness meter, and determine the height of the highest part of the reinforced part as the reinforced part and the height with reference to the lowest part of the non-reinforced part. The height is obtained as the raised height of the portion other than the reinforcing portion. The highest part of the non-reinforced part is located farther from the reinforced part than the lowest part of the non-reinforced part.

It is also preferable that the balloon is formed so that the area of the portion other than the reinforcing portion is expanded when pressurized. If the balloon is formed in this way, when the balloon is pressurized, a gap is easily formed between the medicine held in the portion other than the reinforcing portion and the reinforcing portion, and the medicine held in the balloon is It becomes easy to be released. For example, in the case of a semi-compliant type balloon, the area of the portion other than the reinforcing portion in the straight tube portion of the balloon is wider when the pressure is 0.51 MPa (5 atm) than when the pressure is 0.20 MPa (2 atm). It is preferable to be formed as described above. In the case of a non-compliant type balloon, the area of the portion other than the reinforcing portion in the straight tube portion of the balloon is wider when the pressure is 2.03 MPa (20 atm) than when the pressure is 0.20 MPa (2 atm). It is preferable to be formed as described above.

The degree of swelling, stretchability, and responsiveness to expansion pressure of parts other than the reinforcement on the outer surface of the balloon can be adjusted by appropriately selecting the material and thickness of the base balloon, the material and thickness of the reinforcement, and the installation mode. can do.

It is preferable that at least a part of the reinforcing portion is provided so as to extend in the axial direction of the balloon. In order to reliably transfer the drug held in the portion other than the reinforcing portion to the blood vessel wall or the like, it is desirable to expand the balloon for a certain period of time in the blood vessel, but if the balloon is expanded, blood flow is hindered. Therefore, in reality, the time for expanding the balloon is limited. However, if at least a part of the reinforcing portion extends in the axial direction of the balloon, a gap extending in the axial direction of the balloon is easily formed between the balloon and the blood vessel wall when the balloon is expanded. That is, when a gap is formed between the balloon and the blood vessel wall between the axially extending portions adjacent to the reinforcing portion, or a portion other than the reinforcing portion swells outward in the radial direction of the balloon from the reinforcing portion. Further, a gap is easily formed between the balloon and the blood vessel wall in the axially extending portion of the reinforcing portion. Therefore, even when the balloon is expanded, it is possible to prevent the blood flow from being completely stopped, and the balloon expansion time can be increased. For example, as shown in FIG. 8C, when the non-reinforcing part 13 is formed so as to rise outward in the radial direction of the balloon from the reinforcing part 12, the non-reinforcing part 13 raised during expansion is the inner wall of the blood vessel or the like. It is possible to form a blood flow path (perfusion part) between the reinforcing part 12 and the inner wall of the blood vessel. By forming this perfusion portion so as to extend along the axial direction of the outer surface of the balloon, it is possible to prevent the blood flow from being completely stopped even if the balloon is expanded, and to extend the balloon expansion time. Will be able to.

It is also preferable that a part of the reinforcing part is provided extending in the axial direction of the balloon and the other part is provided extending spirally in the circumferential direction of the balloon. In this case, in addition to the effects described above, when the balloon is pressurized, expansion of the entire balloon in the radial direction can be suppressed, and a non-compliant balloon can be easily formed. Therefore, it is possible to expand and push the balloon to the stenosis part hardened by calcification or the like, and it is possible to deliver the medicine to the back of the hardened stenosis part.

When the main reinforcing portion and the auxiliary reinforcing portion are provided on the balloon, as shown in FIG. 6, the main reinforcing portion 12A extends in the axial direction of the balloon, and the auxiliary reinforcing portion 12B extends in the circumferential direction of the balloon. It is preferably provided. The portion extending in the circumferential direction may extend in a spiral shape in the circumferential direction, or may extend in a ring shape in the circumferential direction. In this case, assuming that the portion extending in the balloon axial direction of the reinforcing portion is an axially extending portion and the portion extending in the balloon circumferential direction of the reinforcing portion is the circumferentially extending portion, the main reinforcing portion extends in the axial direction. It is preferable to be provided only in the portion. A part of the axially extending portion may be composed of an auxiliary reinforcing portion. It is preferable that the circumferentially extending portion is composed only of the auxiliary reinforcing portion. If the main reinforcing portion and the auxiliary reinforcing portion are provided in this way, a gap is easily formed between the balloon and the blood vessel wall between adjacent axially extending portions of the reinforcing portion, or the reinforcing portion is extended in the axial direction. A gap is likely to be formed between the balloon and the blood vessel wall in the existing portion, and the blood flow when the balloon is expanded can be maintained, so that the time required for balloon expansion can be increased.

When the main reinforcing portion and the auxiliary reinforcing portion are provided on the balloon, as shown in FIG. 7, the main reinforcing portion 12A is provided so as to extend spirally in the circumferential direction of the balloon, and the auxiliary reinforcing portion 12B is provided around the balloon. It is also preferable to extend in a spiral direction opposite to the main reinforcing portion in the direction. In this case, if a portion extending in a spiral shape in one direction is a first spiral extending portion and a portion extending in a spiral shape in the other direction is a second spiral extending portion in the reinforcing portion, The reinforcing portion is preferably provided only in the first spiral extending portion, and a part of the first spiral extending portion may be constituted by an auxiliary reinforcing portion. It is preferable that the second spirally extending portion is composed only of the auxiliary reinforcing portion. The balloon thus configured may further have an axially extending portion as a reinforcing portion, but in this case, the axially extending portion is preferably composed only of an auxiliary reinforcing portion. . If the main reinforcement part and the auxiliary reinforcement part are provided in this way, the main reinforcement part bites into the stenosis part and the lesion part so that it is oblique to the extending direction of the blood vessel, and the blood vessel is expanded in the entire circumferential direction. It becomes easy to let you. Therefore, it becomes easier to exert the scoring function by the reinforcing part, and when the balloon is expanded, the stenotic part and the lesioned part are expanded and the medicine held in the balloon is easily delivered to the back of the stenotic part and the lesioned part. .

When the reinforcing portion has an axially extending portion, the balloon is preferably folded and folded at the axially extending portion of the reinforcing portion before expansion. By folding the balloon in this manner, it is possible to suppress the drug held in the portion other than the reinforcing portion from being eluted into the blood or falling off during the delivery of the balloon.

From the viewpoint of enhancing the drug release when the balloon is pressurized, it is also preferable that the balloon is formed to extend in the axial direction rather than the radial direction when pressurized. In conventional drug-eluting balloon catheters, expansion in the radial direction cannot be suppressed, and the balloon diameter is set to a predetermined outer diameter because it is pressurized with a high expansion pressure to expand a stenosis or lesion. In some cases, the blood vessel would be adversely affected by becoming larger. However, by forming the balloon as described above, the outer surface of the balloon is easily spread in the plane direction while suppressing expansion in the radial direction, and is held in a portion other than the reinforcing portion when the balloon is pressurized. This makes it easier to release drugs. In order to obtain such a balloon, for example, in the balloon shown in FIG. 3, the elastic modulus of the fiber material 21 extending in the axial direction is lower than the elastic modulus of the

fiber materials

22 and 23 extending in the circumferential direction. Alternatively, it is preferable to make the line width of the fiber material 21 extending in the axial direction thinner than the line width of the

fiber materials

22 and 23 extending in the circumferential direction.

For example, in the case of a semi-compliant type balloon, the length of the straight tube portion when the pressure is 0.20 MPa (2 atm) is L2, the outer diameter is D2, and the straight tube portion is 0.51 MPa (5 atm). When the axial length is L5 and the outer diameter is D5, the axial length change rate (L5-L2) / L2 should be greater than the outer diameter change rate (D5-D2) / D2. Is preferred. The rate of change in length in the axial direction (L5-L2) / L2 is preferably 2% or more, more preferably 5% or more, and even more preferably 10% or more. The upper limit of the axial length change rate (L5-L2) / L2 is preferably 20% or less, more preferably 15% or less, from the viewpoint of easy application of the drug to a desired site such as a blood vessel wall.

In the case of a non-compliant type balloon, the straight tube portion when the pressure is 0.20 MPa (2 atm) is L2 and the outer diameter is D2, and the straight tube portion is 2.03 MPa (20 atm). When the length in the axial direction is L20 and the outer diameter is D20, the rate of change in axial length (L20-L2) / L2 must be greater than the rate of change in outer diameter (D20-D2) / D2. Is preferred. The rate of change in length in the axial direction (L20-L2) / L2 is preferably 2% or more, more preferably 5% or more, and even more preferably 10% or more. The upper limit of the axial length change rate (L20-L2) / L2 is preferably 20% or less, and more preferably 15% or less, from the viewpoint of easy application of the drug to a desired location on the blood vessel wall.

The balloon may be formed to shrink in the axial direction before expansion. FIG. 9 shows a schematic cross-sectional view of the balloon in the axial direction. When the reinforcing portion has a circumferentially extending portion, the balloon is moved from the state of FIG. 9A to the state of FIG. By making it the state shrunk into, the depth with respect to the reinforcement part 12 of parts other than the reinforcement part 12 (FIG. 9 non-reinforcement part 13) can be formed deeply. That is, when viewed from the inner surface of the balloon, the portion other than the reinforcing portion 12 can be formed so as to bulge inward in the radial direction. By forming the balloon in this way, it is possible to increase the amount of drug that can be held in a portion other than the reinforcing portion 12. The circumferentially extending portion of the reinforcing portion may extend in a spiral shape in the circumferential direction, or may extend in a ring shape in the circumferential direction.

Although the method for producing the balloon catheter of the present invention is not particularly defined, for example, the following method is shown as a method for holding the drug only in the portion other than the reinforcing portion. That is, a manufacturing method including a step of preparing a base balloon, a step of holding a drug on the base balloon, and a step of forming a reinforcing layer on the base balloon holding the drug; a step of forming a reinforcing layer on the base balloon; A manufacturing method including a step of holding a drug on a base balloon having a layer and a step of removing the drug on the reinforcing layer; a step of forming a reinforcing layer having a material or surface that does not hold the drug on the base balloon, and reinforcement thereof Examples thereof include a production method including a step of holding a drug in a base balloon having a layer.

This application claims the benefit of priority based on Japanese Patent Application No. 2016-132846 filed on July 4, 2016. The entire contents of the specification of Japanese Patent Application No. 2016-132846 filed on July 4, 2016 are incorporated herein by reference.

1: Balloon catheter 2: Shaft 3: Inner tube 4: Outer tube 5: Hub 10: Balloon 11:

Base balloon

12, 12A, 12B: Reinforced portion 13: Non-reinforced portion 14: Straight tube portion 15: Proximal side taper portion 16: Distal taper

Claims

A balloon catheter having a shaft and a balloon provided outside the shaft,
The balloon has a base balloon and a reinforcing portion arranged in a linear or net shape on the outer surface of the base balloon, and the reinforcing portion is formed to protrude from the outer surface of the balloon,
A balloon catheter, wherein a drug is held in a portion other than the reinforcing portion on the outer surface of the balloon.
The balloon catheter according to claim 1, wherein the reinforcing portion has a height of 0.1 mm to 0.5 mm.
The balloon catheter according to claim 1 or 2, wherein a portion other than the reinforcing portion is formed on the outer surface of the balloon in a size not including a circle having a diameter of 1.5 mm.
The balloon catheter according to any one of claims 1 to 3, wherein the reinforcing portion is arranged in a mesh shape including a pentagon or more polygon.
The portion other than the reinforcing portion on the outer surface of the balloon is formed so as to rise outward in the radial direction of the balloon when a pressure of 0.51 MPa (5 atm) is applied. Balloon catheter.
The portion other than the reinforcing portion on the outer surface of the balloon is formed so as to rise outward in the radial direction of the balloon when a pressure of 2.03 MPa (20 atm) is applied. Balloon catheter.
The portion other than the reinforcing portion on the outer side surface of the balloon is formed so as to swell outward in the radial direction of the balloon from the reinforcing portion when a pressure of 0.51 MPa (5 atm) is applied. The balloon catheter according to claim 1.
The portion other than the reinforcing portion on the outer surface of the balloon is formed so as to swell outward in the radial direction of the balloon from the reinforcing portion when a pressure of 2.03 MPa (20 atm) is applied. The balloon catheter according to claim 1.
The balloon catheter according to any one of claims 1 to 8, wherein at least a part of the reinforcing portion extends in the axial direction of the balloon.
The part of the reinforcing part is provided to extend in the axial direction of the balloon, and the other part is provided to extend spirally in the circumferential direction of the balloon. Balloon catheter.
The balloon has an axial length L2 and an outer diameter D2 at a pressure of 0.20 MPa (2 atm), and an axial length of the straight pipe at a pressure of 0.51 MPa (5 atm). 11. The length change rate (L5-L2) / L2 in the axial direction is greater than the change rate (D5-D2) / D2 of the outer diameter, where L5 is the outer diameter and D5 is the outer diameter. The balloon catheter according to claim 1.
The balloon has an axial length L2 and an outer diameter D2 when the pressure is 0.20 MPa (2 atm), and the axial length of the straight pipe when the pressure is 2.03 MPa (20 atm). The axial length change rate (L20-L2) / L2 is greater than the outer diameter change rate (D20-D2) / D2, where L20 is the outer diameter and D20 is the outer diameter. The balloon catheter according to claim 1.
The balloon catheter according to any one of claims 1 to 12, wherein the reinforcing portion is formed by bonding a fiber material to an outer surface of the base balloon.
The balloon catheter according to any one of claims 1 to 13, wherein the drug is an antiproliferative agent or an immunosuppressive agent.