Balloon for balloon catheter and balloon catheter

Abstract

In a balloon (10) for a balloon catheter, a straight tube section (13) of the balloon (10) is provided with a bead (17) extending in the longitudinal direction, the bead (17) is provided with a plurality of cutouts (19) disposed in the longitudinal direction, and when the bead (17) is divided into a proximal section (21), an intermediate section (22), and a distal section (23) in the longitudinal direction, the cutouts (19) are provided at least in the distal section (23) and the intermediate section (22). The deepest depth of the cutouts (19) provided in the distal sections (23) is formed to be deeper than the deepest depth of the cutouts (19) provided in the intermediate sections (22).

Description

Technical Field

[0001] The present invention relates to a balloon for a balloon catheter and a balloon catheter equipped with the balloon. Background Art

[0002] As is well known, narrowing of blood vessels, the pathways through which blood circulates in the body, impairs blood circulation and can lead to various diseases. In particular, narrowing of the coronary arteries that supply blood to the heart can lead to serious illnesses such as angina pectoris and myocardial infarction. One method for treating such vascular narrowing is angioplasty (PTA, PTCA, etc.), which uses a balloon catheter to dilate the narrowed area.

[0003] Balloon catheters are known to have structures with ridges on the surface of the balloon (e.g., Patent Documents 1 to 3). If such a balloon catheter is used, when the balloon is expanded, the ridges of the balloon can bite into the stenosis to effectively expand the stenosis. On the other hand, balloons provided with ridges tend to have higher rigidity in the portion provided with the ridges, and the bendability in the longitudinal direction tends to decrease. In contrast, balloon catheters are known to have incisions formed in the ridges on the surface of the balloon (e.g., Patent Documents 4 and 5). If such a balloon catheter is used, even a balloon provided with ridges can ensure bendability in the longitudinal direction.

[0004] Patent Document 1: International Publication No. 2020 / 250611

[0005] Patent Document 2: Japanese Patent Application Laid-Open No. 2009-112361

[0006] Patent Document 3: Japanese Patent Application Laid-Open No. 2013-176507

[0007] Patent Document 4: International Publication No. 2012 / 099950

[0008] Patent Document 5: International Publication No. 2020 / 255923

[0009] A balloon having ridges on its surface and notches formed in the ridges allows the ridges to function as scoring elements, while also ensuring the balloon's flexibility in the longitudinal direction through the notches formed in the ridges. On the other hand, since blood vessels often have large bends, it is desirable to ensure smooth insertion of a balloon with ridges even in such bends. Summary of the Invention

[0010] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a balloon for a balloon catheter having ridges provided on its surface and capable of improving insertability into a curved portion such as a blood vessel, and a balloon catheter including the balloon.

[0011] The balloon for a balloon catheter of the present invention, which can solve the above-mentioned problems, and the balloon catheter including the balloon are as follows.

[0012] [1] A balloon for a balloon catheter, having a long axis extending from a proximal side to a distal side, a radial direction perpendicular to the long axis, and a circumferential direction, wherein:

[0013] The balloon comprises a straight tube portion, a proximal tapered portion located closer to the proximal side than the straight tube portion, and a distal tapered portion located farther from the distal side than the straight tube portion.

[0014] The straight tube portion comprises: a cylindrical balloon body portion; and a convex strip protruding radially outward from the outer surface of the balloon body portion and extending in the longitudinal direction.

[0015] The ridges are provided with a plurality of cutouts arranged along the longitudinal direction.

[0016] When the convex strip is divided into three equal parts along the longitudinal direction into a proximal section, a middle section, and a distal section, the cutout is provided at least in the distal section and the middle section.

[0017] The deepest depth of the incision provided in the distal section is deeper than the deepest depth of the incision provided in the intermediate section.

[0018] [2] The balloon according to [1], wherein:

[0019] The above-mentioned incisions are respectively provided in the above-mentioned proximal section, the above-mentioned middle section and the above-mentioned distal section, and the deepest depth of the above-mentioned incision provided in the above-mentioned distal section and the deepest depth of the above-mentioned incision provided in the above-mentioned proximal section are deeper than the deepest depth of the above-mentioned incision provided in the above-mentioned middle section.

[0020] [3] The balloon according to [1] or [2], wherein:

[0021] The number of the incisions provided in the distal section is greater than the number of the incisions provided in the intermediate section.

[0022] [4] The balloon according to any one of [1] to [3], wherein:

[0023] The number of the incisions provided in the distal section and the number of the incisions provided in the proximal section are greater than the number of the incisions provided in the intermediate section.

[0024] [5] The balloon according to any one of [1] to [4], wherein

[0025] The distal section is provided with a plurality of the incisions having different depths.

[0026] [6] The balloon according to any one of [1] to [5], wherein:

[0027] A plurality of the incisions having different depths are provided in the proximal section and the distal section, respectively.

[0028] [7] The balloon according to any one of [1] to [6], wherein:

[0029] The ridges are made of resin, metal or a combination thereof.

[0030] [8] The balloon according to any one of [1] to [7], wherein:

[0031] The length of the straight tube portion in the longitudinal direction is 50 mm or more.

[0032] [9] A balloon catheter comprising the balloon according to any one of [1] to [8].

[0033] The balloon catheter balloon of the present invention has ridges on the outer surface of its straight tube. Therefore, when the balloon is inflated at a stenotic site in a blood vessel using a balloon catheter equipped with this balloon, the ridges bite into the stenosis, effectively dilating the area. Furthermore, the ridges are notched, with deeper notches formed in the distal section of the ridges, thereby enhancing the bendability of the distal portion of the balloon. This makes it easier to insert the balloon into a curved area. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A configuration example of a balloon catheter according to an embodiment of the present invention is shown, and a side view of the balloon catheter is shown.

[0035] Figure 2 express Figure 1 A II-II cross-sectional view of the balloon catheter is shown.

[0036] Figure 3 express Figure 1 The balloon catheter is shown in cross-sectional view III-III.

[0037] Figure 4 An example of a perspective view showing a balloon included in a balloon catheter.

[0038] Figure 5 express Figure 4 A vertical cross-sectional view of the straight tube portion of the balloon in the longitudinal direction is shown.

[0039] Figure 6 express Figure 5 A vertical cross-sectional view of the long axis direction of the ridge of the balloon shown.

[0040] Figure 7An example of a cross-sectional view along the longitudinal direction of ridges and cutouts provided on a balloon is shown.

[0041] Figure 8 Another example of a cross-sectional view along the longitudinal direction of ridges and cutouts provided on the balloon is shown.

[0042] Figure 9 Another example of a cross-sectional view along the longitudinal direction of ridges and cutouts provided on the balloon is shown.

[0043] Figure 10 Another example of a cross-sectional view along the longitudinal direction of ridges and cutouts provided on the balloon is shown.

[0044] Figure 11 Another example of a perspective view showing a balloon included in a balloon catheter.

[0045] Figure 12 Another example of a vertical cross-sectional view showing the longitudinal direction of a ridge of a balloon. DETAILED DESCRIPTION

[0046] The present invention will be described in detail below based on the following embodiments. However, the present invention is not limited to the following embodiments and can be implemented with appropriate modifications within the scope of the preceding and following descriptions, all of which are included within the technical scope of the present invention. In addition, for convenience, hatching and component reference numerals may be omitted in the drawings. In such cases, please refer to the specification and other drawings. Furthermore, the dimensions of various components in the drawings are primarily intended to facilitate understanding of the features of the present invention and may differ from actual dimensions.

[0047] A balloon for a balloon catheter and a configuration example of a balloon catheter including the balloon according to an embodiment of the present invention will be described with reference to the drawings. Figures 1 to 4 A configuration example of a balloon catheter is shown. Figure 1 A side view of a balloon catheter is shown. Figure 2 express Figure 1 The II-II cross-sectional view of the balloon catheter shown, Figure 3 express Figure 1 The III-III cross-sectional view of the balloon catheter shown, Figure 4 An example of a perspective view showing a balloon included in a balloon catheter. Figure 1 A configuration example of a rapid-exchange balloon catheter is shown.

[0048] A balloon catheter 1 includes a shaft 2 and a balloon 10 disposed outside the shaft 2. The balloon catheter 1 has a proximal side and a distal side, with the balloon 10 disposed on the distal portion of the shaft 2. The proximal side of the balloon catheter 1 refers to the direction of the user's (the person performing the surgery) hand relative to the direction of extension of the balloon catheter 1, while the distal side refers to the direction opposite to the proximal side, i.e., toward the treatment target. The direction from the proximal side to the distal side of the balloon catheter 1 is referred to as the long axis.

[0049] The balloon catheter 1 is configured to supply fluid to the interior of the balloon 10 via the shaft 2, enabling the use of a balloon pressure regulator to control the expansion and contraction of the balloon 10. The fluid may also be a pressurized fluid pressurized by a pump or the like. Hereinafter, the fluid supplied to the interior of the balloon 10 will be referred to as the "balloon inflation fluid."

[0050] The shaft 2 is composed of, for example, an inner shaft 3 and an outer shaft 4. The inner shaft 3 is disposed within the lumen of the outer shaft 4. The inner shaft 3 can function as an insertion passage for a guidewire that guides the movement of the shaft 2. When the balloon catheter 1 is used, the guidewire is inserted through the lumen of the inner shaft 3. The space between the inner shaft 3 and the outer shaft 4 can function as a flow path for a balloon inflation fluid.

[0051] In the rapid exchange balloon catheter 1, a guidewire port 7 is provided midway from the distal side to the proximal side of the shaft 2, the proximal end of the inner shaft 3 is connected to the guidewire port 7, and the distal end of the inner shaft 3 extends to the distal part of the shaft 2, thereby forming a guidewire insertion path extending from the guidewire port 7 to the distal part of the shaft 2.

[0052] The outer shaft 4 may also include a proximal outer shaft 4A and a distal outer shaft 4B. In this case, the inner shaft 3 is preferably arranged in the inner cavity of the distal outer shaft 4B. The proximal outer shaft 4A and the distal outer shaft 4B may be made of the same material or different materials. For example, the proximal outer shaft 4A is preferably made of resin or metal, and the distal outer shaft 4B is preferably made of resin. In addition, the outer shaft 4 may not be divided into the proximal outer shaft 4A and the distal outer shaft 4B, but may be made of only one component. Alternatively, the proximal outer shaft 4A and the distal outer shaft 4B may be made of multiple tubular components.

[0053] A hub 5 is preferably provided on the proximal side of the shaft 2. The hub 5 preferably has a fluid injection portion 6 that communicates with the flow path of the balloon inflation fluid of the shaft 2. The balloon 10, the shaft 2 (inner shaft 3, outer shaft 4), and the hub 5 can be joined using conventionally known joining means such as adhesives and heat welding.

[0054] Furthermore, although not shown in the accompanying drawings, the balloon catheter may also be an integrally interchangeable balloon catheter in which the inner shaft extends from the distal portion of the shaft to the proximal portion, and a guidewire insertion passage is formed from the distal side to the proximal side of the shaft. In this case, the flow path for the balloon inflation fluid and the guidewire insertion passage provided in the shaft preferably extend to a hub portion, and the hub portion is configured to include: a fluid injection portion connected to the flow path for the balloon inflation fluid; and a treatment portion connected to the guidewire insertion passage. The hub portion preferably has a bifurcated structure, with the fluid injection portion provided on one side of the bifurcated shaft and the treatment portion provided on the other side.

[0055] The outer surface of the shaft 2 is preferably coated. In a rapid-exchange balloon catheter 1, the outer surface of one or both of the proximal outer shaft 4A and the distal outer shaft 4B is preferably coated, and more preferably, the outer surfaces of both the proximal outer shaft 4A and the distal outer shaft 4B are coated. In a fully exchangeable balloon catheter, the outer surface of the outer shaft is preferably appropriately coated.

[0056] The coating can be either a hydrophilic coating or a hydrophobic coating, depending on the intended purpose. The outer surface of the shaft 2 can be coated by immersing the shaft 2 in a hydrophilic or hydrophobic coating agent, applying a hydrophilic or hydrophobic coating agent to the outer surface of the shaft 2, or covering the outer surface of the shaft 2 with a hydrophilic or hydrophobic coating agent. The coating agent may also contain a chemical or additive.

[0057] Examples of the hydrophilic coating agent include hydrophilic polymers such as polyvinyl alcohol, polyethylene glycol, polyacrylamide, polyvinyl pyrrolidone, and methyl vinyl ether maleic anhydride copolymer, and hydrophilic coating agents prepared by any combination thereof.

[0058] Examples of hydrophobic coating agents include polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), perfluoroalkoxyalkanes (PFA), silicone oils, hydrophobic polyurethane resins, carbon coatings, diamond coatings, diamond-like carbon (DLC) coatings, ceramic coatings, and substances with low surface free energy terminated with alkyl groups or perfluoroalkyl groups.

[0059] The distal end of the balloon catheter 1 is preferably provided with a tip 8. The tip 8 may be provided as a separate component from the inner shaft 3 and further distal to the distal end of the inner shaft 3, or the inner shaft 3 may be extended to further distal to the distal end of the balloon 10 so that the distal end of the inner shaft 3 functions as the tip 8.

[0060] In order to confirm the position of the balloon 10 under X-ray fluoroscopy, an X-ray opaque marker 9 may be arranged on the shaft 2 at the portion where the balloon 10 is located in the longitudinal direction. The X-ray opaque marker 9 can be arranged, for example, on the inner shaft 3 arranged inside the balloon 10, preferably at positions corresponding to both ends of the straight tube portion of the balloon 10, or at a position corresponding to the center of the straight tube portion of the balloon 10.

[0061] The balloon 10 has a long axis and a radial direction and is formed into a cylindrical shape with openings on the proximal side and the distal side (see Figure 4 The radial direction of the balloon 10 is a direction perpendicular to the longitudinal axis and extending radially from the center of the balloon 10. The balloon 10 also has a circumferential direction as a direction along the outer periphery of the balloon 10 in the expanded state in a vertical cross section of the balloon 10 in the longitudinal axis direction.

[0062] The balloon 10 has, in the longitudinal direction, a straight tube portion 13; a proximal tapered portion 12 located closer to the longitudinal side than the straight tube portion 13; and a distal tapered portion 14 located more distally than the straight tube portion 13. The straight tube portion 13 is formed into a roughly cylindrical shape extending in the longitudinal direction, and its radial length (outer diameter) is formed to be the largest in the balloon 10. The proximal tapered portion 12 is located on the proximal side of the straight tube portion 13 and is connected to the proximal end of the straight tube portion 13. The proximal tapered portion 12 is formed so that its outer diameter becomes smaller as it moves away from the straight tube portion 13. The distal tapered portion 14 is located on the distal side of the straight tube portion 13 and is connected to the distal end of the straight tube portion 13. The distal tapered portion 14 is formed so that its outer diameter becomes smaller as it moves away from the straight tube portion 13. The balloon 10 further preferably includes a proximal sleeve portion 11 located proximal to the proximal tapered portion 12, and a distal sleeve portion 15 located distal to the distal tapered portion 14. The proximal sleeve portion 11 is located proximal to the proximal tapered portion 12 and connected to the proximal end of the proximal tapered portion 12. The proximal sleeve portion 11 is formed into a generally cylindrical shape. The distal sleeve portion 15 is located distal to the distal tapered portion 14 and connected to the distal end of the distal tapered portion 14. The distal sleeve portion 15 is formed into a generally cylindrical shape.

[0063] By configuring the balloon 10 as described above, when the balloon 10 is expanded at a stenosis, the straight tube portion 13 is in full contact with the stenosis, facilitating treatment such as dilation of the stenosis. Furthermore, the balloon 10 includes the proximal tapered portion 12 and the distal tapered portion 14. This allows the outer diameters of the proximal and distal ends of the balloon 10 to be reduced when the balloon 10 is deflated, thereby reducing the height difference between the shaft 2 and the balloon 10. This facilitates insertion of the balloon 10 into body cavities, into the forceps channel of an endoscope, and into delivery catheters such as guide catheters.

[0064] Preferably, at the distal portion of the shaft 2, the inner shaft 3 extends distally beyond the distal end of the outer shaft 4, and the inner shaft 3 extends from the proximal sleeve portion 11 to the distal sleeve portion 15 within the interior space of the balloon 10. Furthermore, preferably, the outer surface of the inner shaft 3 is bonded to the inner surface of the distal sleeve portion 15 of the balloon 10, and the outer surface of the outer shaft 4 is bonded to the inner surface of the proximal sleeve portion 11 of the balloon 10. By configuring the distal portion of the shaft 2 in this manner, a balloon inflation fluid can be supplied to the interior space of the balloon 10 through the space between the inner shaft 3 and the outer shaft 4.

[0065] The size of the balloon 10 is not particularly limited and can be appropriately set within the range of, for example, a length of the straight tube portion 13 in the longitudinal direction of 4 mm to 400 mm and an outer diameter of the straight tube portion 13 of 1 mm to 30 mm.

[0066] The balloon 10 (particularly the balloon body 16) is preferably made of a resin, more preferably a thermoplastic resin. This makes it easy to manufacture the balloon 10 by molding. Examples of the resin that constitutes the balloon 10 include polyolefin resins such as polyethylene, polypropylene, and ethylene-propylene copolymers, polyester resins such as polyethylene terephthalate and polyester elastomers, polyurethane resins such as polyurethane and polyurethane elastomers, polyamide resins such as polyphenylene sulfide resins, polyamide and polyamide elastomers, fluorine-based resins, silicone resins, and natural rubbers such as latex rubber. One or more of these resins may be used alone, or two or more may be used in combination. Among these, polyamide resins, polyester resins, and polyurethane resins are preferably used. In particular, from the perspective of the filmization and flexibility of the balloon 10, elastomeric resins are preferably used. For example, among polyamide resins, materials suitable for the balloon 10 include nylon 12 and nylon 11. Nylon 12 is preferably used because it is relatively easy to form when blow-molded. In addition, polyamide elastomers such as polyetheresteramide elastomer and polyamideether elastomer are preferably used from the viewpoints of thin film and flexibility of the balloon 10. Among them, polyetheresteramide elastomer is preferably used from the viewpoints of high yield strength and good dimensional stability of the balloon 10.

[0067] The balloon 10 has ridges 17 on the outer surface of the straight tube portion 13. Providing ridges 17 on the outer surface of the straight tube portion 13 provides the balloon 10 with a scoring function. When the balloon 10 is expanded in a stenotic region of a blood vessel, the ridges 17 can penetrate into the calcified stenosis, creating cracks therein. This prevents dissociation of the blood vessel and dilates the stenosis. Furthermore, the balloon 10 can achieve a higher pressure resistance and prevent excessive expansion during pressurization. Furthermore, the balloon 10 can also be used to treat stenosis and lesions in body cavities other than blood vessels. However, the following description focuses on the application of the balloon 10 in vascular treatment.

[0068] Reference Figure 5 and Figure 6The ridges 17 of the balloon 10 will be described in detail. Figure 5 A vertical cross-sectional view of the straight tube portion 13 of the balloon 10 in the longitudinal direction is shown. Figure 6 An enlarged cross-sectional view of the rib 17 of the balloon 10 is shown. Figure 5 Shown Figure 4 In the illustrated structural example of a vertical cross section of the straight tube portion 13 of the balloon 10 in the longitudinal direction, the ridges 17 are provided at three locations in the circumferential direction of the straight tube portion 13 .

[0069] The straight tube portion 13 of the balloon 10 includes a cylindrical main body 16, with ridges 17 provided on the outer surface of the main body 16. The ridges 17 are provided to protrude radially outward from the outer surface of the main body 16. The provision of the ridges 17 creates a ridge-containing region 24 and a ridge-free region 25 on the outer surface of the straight tube portion 13. As described later, the ridge-containing region 24 also includes portions of the ridges 17 where notches 19 are formed. The outer surface of the straight tube portion 13 is preferably flat in the ridge-free region 25. For example, the outer surface of the straight tube portion 13 is preferably not concave in the ridge-free region 25. This facilitates uniform expansion of the balloon 10 and facilitates the desired scoring function of the ridges 17. Furthermore, the flat outer surface of the straight tube portion 13 in the ridge-free region 25 means that the ridge-free region 25 is a flat surface curved into an arch shape, with no concavities or convexities formed on the curved surface. This unevenness does not include surface roughness inevitably formed during manufacturing.

[0070] The ridge 17 has a top 17A and a base 17B. The top 17A refers to the front end of the ridge 17, that is, the radially outermost portion of the ridge 17, and the base 17B refers to the boundary with the balloon body 16, that is, the radially innermost portion of the ridge 17.

[0071] The ridges 17 can be made of, for example, a resin. If the ridges 17 are made of a resin, the balloon 10 having the ridges 17 can be manufactured by resin molding, making manufacturing easier. In this case, the ridges 17 and the balloon main body 16 are preferably made of the same resin, and the ridges 17 and the balloon main body 16 are preferably molded integrally. The balloon main body 16 may also have an inner layer and an outer layer. In this case, the ridges 17 are preferably made of the same resin as the outer layer of the balloon main body 16. As a result, it is less likely that the ridges 17 will accidentally fall off the balloon main body 16. Alternatively, as long as the resin constituting the ridges 17 and the resin constituting the balloon main body 16 have a certain degree of compatibility, the ridges 17 and the balloon main body 16 may be made of different resins.

[0072] The ridges 17 can be made of metal or a combination of metal and resin. In this case, the portion including the top 17A of the ridges 17 is preferably made of metal. This facilitates the formation of cracks in or incision of the stenosis by the ridges 17 when the balloon 10 is expanded. For example, the entire ridge 17 can be made of metal, or the portion including the base 17B of the ridge 17 can be made of resin, while the portion including the top 17A of the ridge 17 is made of metal. Therefore, the ridges 17 are preferably made of resin, metal, or a combination thereof.

[0073] In the straight tube portion 13, the balloon main body 16 is defined as a cylindrical portion. The portion of the straight tube portion 13, excluding the radially outwardly projecting ridges 17, constitutes the balloon main body 16. The balloon main body 16 can be considered to have a cylindrical outer surface. Therefore, in a vertical cross-section taken along the longitudinal axis of the straight tube portion 13, the balloon main body 16 has a substantially circular outer shape, making it possible to distinguish between the balloon main body 16 and the ridges 17. The ridge-existing region 24 is comprised of the balloon main body 16 and the ridges 17, while the ridge-free region 25 is comprised of the balloon main body 16.

[0074] The ridges 17 are arranged to extend in a ridge-like manner on the outer surface of the straight tube portion 13. The ridges 17 extend approximately parallel to the longitudinal axis of the balloon 10. In the straight tube portion 13 of the balloon 10, a plurality of ridges 17 are provided at different circumferential positions. That is, the ridges 17 are provided at multiple locations along the circumference of the balloon 10. In this case, the ridges 17 are preferably arranged at approximately equal intervals along the circumference of the straight tube portion 13 of the balloon 10. Thus, when the balloon 10 is expanded, cracks can be formed at multiple locations in the narrow portion. The ridges 17 are preferably provided at two or more locations, more preferably at three or more locations, more preferably at 12 or fewer locations, more preferably at 10 or fewer locations, and even more preferably at 8 or fewer locations, relative to the circumference of the balloon 10. In addition, the circumferential spacing of the ridges 17 in this case is preferably longer than the circumferential length of one ridge 17.

[0075] The plurality of ridges 17 are preferably provided at substantially the same position in the longitudinal direction. That is, the proximal ends of the plurality of ridges 17 are preferably located at substantially the same position in the longitudinal direction, and the distal ends of the plurality of ridges 17 are preferably located at substantially the same position in the longitudinal direction.

[0076] The cross-sectional shape of the ridges 17 is not particularly limited. For example, the shape of the ridges 17 in a cross-section perpendicular to the longitudinal axis of the straight tube portion 13 may include a triangle, a polygon such as a quadrilateral, a partial circular shape such as a semicircle or a fan, a wedge, a convex shape, a spindle, or an irregular shape. Polygonal shapes include shapes with clearly defined corners and straight sides, as well as shapes with rounded corners and at least partially curved sides. Furthermore, the ridges 17 are preferably formed so that their width gradually decreases toward their apex 17A.

[0077] In a vertical cross-section of the straight tube portion 13 taken along the longitudinal axis, the height of the ridge 17 is preferably at least 0.2 times the width (maximum width) of the ridge 17. Forming the ridge 17 in this manner allows the ridge 17 to easily dig into the narrowed portion when the balloon 10 is expanded, thereby enhancing the scoring function of the ridge 17. The width of the ridge 17 described herein refers to the circumferential length of the ridge 17. The ridge 17 is preferably formed so as to have its maximum width at the base 17B, thereby stably positioning the ridge 17 on the outer surface of the balloon body 16. The height of the ridge 17 is more preferably at least 0.4 times the width of the ridge 17, and further preferably at least 0.7 times. On the other hand, the height of the ridge 17 is preferably at most 2.0 times the width of the ridge 17, more preferably at most 1.8 times, and further preferably at most 1.5 times. This makes it easier to ensure the flexibility of the balloon 10 in the portion where the ridge 17 is present.

[0078] In the straight tube portion 13, the wall thickness of the portion provided with the ridges 17, that is, the wall thickness of the ridge-existing region 24, is preferably greater than the wall thickness of the portion not provided with the ridges 17, that is, the wall thickness of the ridge-free region 25. This improves the scoring function of the ridges 17. The wall thickness (maximum wall thickness) of the ridge-existing region 24 is preferably 1.5 times or greater, more preferably 2.0 times or greater, and even more preferably 2.5 times or greater, of the wall thickness (maximum wall thickness) of the ridge-free region 25. The upper limit of the wall thickness of the ridge-existing region 24 is not particularly limited; for example, it can be 30 times or less, 20 times or less, or 10 times or less of the wall thickness of the ridge-free region 25.

[0079] In balloon 10, ridges 17 are preferably provided over 60% or more of the longitudinal axis of straight tube portion 13, more preferably over 70% or more, and even more preferably over 80% or more. This allows cracks to form over a wide area of the stenosis when balloon 10 is expanded. Ridges 17 can be provided over 90% or more of the longitudinal axis of straight tube portion 13, or over substantially the entire longitudinal axis of straight tube portion 13. Furthermore, ridges 17 can be provided on the outer surfaces of proximal tapered portion 12 and / or distal tapered portion 14.

[0080] The balloon 10 may also have inner ridges (not shown) protruding radially inward from the inner surface of the balloon 10. The ridges 17 and the inner ridges may also be arranged at the same position in the longitudinal direction and circumferential direction of the balloon 10, and preferably they may be integrally formed, thereby forming a portion of the balloon 10 with a thick wall.

[0081] The balloon 10 provided with the ribs 17 tends to have higher rigidity in the portion provided with the ribs 17. Therefore, the bendability of the balloon 10 provided with the ribs 17 in the longitudinal direction tends to be reduced compared to the balloon 10 not provided with the ribs 17. For example, in the shunt formed during hemodialysis, the blood vessel is greatly bent at the arteriovenous anastomosis, but when the balloon is passed through such a portion, it may be difficult to pass the balloon provided with the ribs through the arteriovenous anastomosis. Alternatively, in a balloon for lower limbs, the balloon is inserted into the iliac artery during treatment, but the blood vessel is greatly bent in the branch portion where the left and right iliac arteries branch from the abdominal aorta. Therefore, when the balloon for lower limbs is provided with ribs, it may be difficult to pass the balloon from one of the left and right iliac arteries to the other. In particular, the length of the balloon for lower limbs is long, and therefore the possibility that the balloon cannot pass through the portion where the blood vessel is greatly bent becomes higher. Therefore, as Figure 4 As shown in FIG. 1 , in the balloon 10, the ridges 17 are provided with cutouts 19. By forming the cutouts 19 in the ridges 17, the flexibility of the balloon 10 in the longitudinal direction can be improved.

[0082] It is preferable that the cutouts 19 are formed in the respective ridges 17. Thus, the bendability of the balloon 10 can be improved regardless of the direction in which the balloon 10 bends.

[0083] The number of cutouts 19 formed in each ridge 17 is not particularly limited as long as it is one or more. However, from the perspective of improving the flexibility of the balloon 10, the number of cutouts 19 formed in each ridge 17 is preferably two or more, more preferably three or more. On the other hand, from the perspective of ensuring the scoring function of the balloon 10, the number of cutouts 19 formed in each ridge 17 is preferably 20 or less, more preferably 16 or less, even more preferably 12 or less, and even more preferably 8 or less.

[0084] The cutout 19 may be formed by cutting away a portion of the top portion 17A of the ridge 17 extending in the longitudinal direction. Figures 7 to 10 Various examples of forming the cutout 19 are shown. Regarding the ridge 17 and the cutout 19, a cross-sectional view along the long axis direction passing through the top 17A of the ridge 17 is shown (specifically, a cross-sectional view along the long axis direction and the radial direction passing through the top 17A of the ridge 17). Figure 8 As shown, the cutout 19 may be formed to extend from the top 17A of the ridge 17 to the base 17B, as shown in FIG. Figure 7 、 Figure 9 and Figure 10 As shown, the cutout 19 may be formed to extend from the top 17A of the ridge 17 to the middle of the base 17B. In the former case, the depth of the cutout 19 is the same as the height of the ridge 17. In the latter case, the depth of the cutout 19 is formed to be shorter than the height of the ridge 17.

[0085] The cutout 19 has a bottom 19B and a top 19A. The bottom 19B is the radially innermost portion of the cutout 19, and the top 19A is the radially outermost portion of the cutout 19. The top 19A of the cutout 19 corresponds to the proximal end 19P and the distal end 19D of the cutout 19, and coincides with the top 17A of the ridge 17. The radial length from the top 19A to the bottom 19B of the cutout 19 is the depth of the cutout 19.

[0086] The ridge 17 is divided into a plurality of ridge segments 18 by the cutouts 19. Figure 8 As shown, when the cutout 19 is formed to extend from the top 17A of the ridge 17 to the base 17B, the cutout 19 forms a discontinuity 20 of the ridge 17, with ridge segments 18 arranged proximally and distally of the discontinuity 20. The discontinuity 20 has a predetermined length in the longitudinal direction, and the ridge 17 is formed by alternating the ridge segments 18 and the discontinuity 20 in the longitudinal direction. When the cutout 19 is formed to extend from the top 17A of the ridge 17 to midway through the base 17B, the cutout 19 is divided into proximal and distal ridge segments 18, with the bottom 19B of the cutout 19 serving as the boundary.

[0087] The shape of the cutout 19 is not particularly limited. For example, the cutout 19 may be shaped as follows in a cross section along the longitudinal direction passing through the top 17A of the ridge 17. Figure 7 As shown, it is formed into a V shape, or as Figure 9 As shown, it is formed into a U shape, or as Figure 8 and Figure 10 As shown, the shape is formed in a rectangular shape with one side removed. Furthermore, the outer edge of the cutout 19 preferably has, in a cross-section along the major axis through the top 17A of the ridge 17, a portion extending radially outward and obliquely toward the proximal side, and a portion extending radially outward and obliquely toward the distal side closer to the distal side than the portion. The portion of the outer edge of the cutout 19 extending radially outward or distally can extend in a straight line, a curved line, or a combination thereof. More preferably, the outer edge of the proximal side of the cutout 19 is formed as a whole so as to extend radially outward and obliquely toward the proximal side, while the outer edge of the distal side of the cutout 19 is formed as a whole so as to extend radially outward and obliquely toward the distal side, from the bottom 19B of the cutout 19. The length and shape of the cutout 19 will be described in detail below, but these are determined based on the length and shape of the cutout 19 in a cross-section along the major axis through the top 17A of the ridge 17. In addition, a cross section along the major axis direction passing through the top 17A of the ridge 17 means a cross section along the major axis direction and the radial direction passing through the top 17A of the ridge 17 .

[0088] The length of the notch 19 in the longitudinal direction is preferably shorter than the length of the ridge segments 18 in the longitudinal direction. Specifically, in each ridge 17, the length of the notch 19 in the longitudinal direction (if multiple notches 19 are provided, the length of each notch 19 in the longitudinal direction) is preferably shorter than the length of any ridge segment 18 in the longitudinal direction. Furthermore, in each ridge 17, the length of the notch 19 in the longitudinal direction (if multiple notches 19 are provided, the length of each notch 19 in the longitudinal direction) is preferably no greater than 0.5 times the average length of the ridge segments 18 in the longitudinal direction, more preferably no greater than 0.3 times, and even more preferably no greater than 0.2 times. This facilitates ensuring the scoring function of the ridges 17. In addition, the length of the long axis direction of the incision 19 refers to the distance between the tops of the convex segments 18 located on the proximal side and the distal side across the incision 19, that is, the distance between the distal end of the top of the convex segment 18 located on the proximal side and the proximal end of the top of the convex segment 18 located on the distal side across the incision 19.

[0089] In each ridge 17, the total length of the notches 19 in the longitudinal direction is preferably 20% or less, more preferably 15% or less, and even more preferably 10% or less of the longitudinal length of the ridge 17. This facilitates ensuring the scoring function of the ridge 17. The longitudinal length of the ridge 17 is determined as follows: the proximal end of the ridge segment 18 located closest to the proximal side of the plurality of ridge segments 18 constituting each ridge 17 constitutes the proximal end of the ridge 17, the distal end of the ridge segment 18 located furthest from the proximal side constitutes the distal end of the ridge 17, and the longitudinal length from the proximal end to the distal end of the ridge 17 constitutes the longitudinal length of the ridge 17.

[0090] In each incision 19, the length of the incision 19 in the longitudinal direction is preferably at least 0.2 times the depth of the incision 19, more preferably at least 0.3 times, and even more preferably at least 0.5 times. This facilitates improving the bendability of the straight tube portion 13 of the balloon 10 in the longitudinal direction. In each incision 19, the length of the incision 19 in the longitudinal direction is preferably at most 5 times the depth of the incision 19, more preferably at most 3 times, and even more preferably at most 2 times. This facilitates ensuring the scoring function of the balloon 10.

[0091] It is preferable that the length of the portion of the bottom 19B of the cutout 19 extending in parallel with the longitudinal direction is not longer than the longitudinal length of the cutout 19 (the distance between the tops of the ridge segments 18 located on the proximal and distal sides across the cutout 19) (see Figure 8 and Figure 10). In each incision 19, the length of the portion of the bottom 19B of the incision 19 extending parallel to the long axis direction is preferably less than 0.5 times the length of the incision 19 in the long axis direction, more preferably less than 0.3 times, and further preferably less than 0.2 times. As a result, the balloon 10 can be easily bent smoothly at the incision 19, and it is easy to ensure the scoring function based on the ridge 17. The bottom 19B of the incision 19 may also not include a portion extending parallel to the long axis direction. In addition, when the incision 19 is formed to extend from the top 17A of the ridge 17 to the base 17B, the length of the discontinuity 20 of the ridge 17 in the long axis direction (the length of the discontinuity 20 on the outer surface of the balloon body 16 in the long axis direction) is equivalent to the length of the bottom 19B of the incision 19 in the long axis direction.

[0092] like Figure 4 As shown, ridge 17 has a deeper notch 19 formed in the distal portion of ridge 17. Specifically, when ridge 17 is divided into three equal parts along the longitudinal direction, namely, a proximal section 21, an intermediate section 22, and a distal section 23, notches 19 are provided in at least distal section 23 and intermediate section 22. The deepest depth of notch 19 provided in distal section 23 is deeper than the deepest depth of notch 19 provided in intermediate section 22. Forming notches 19 in ridge 17 in this manner improves the flexibility of the distal portion of balloon 10 (specifically, the portion of balloon 10 corresponding to distal section 23 of ridge 17 in the longitudinal direction).

[0093] When inserting the balloon 10 through a curved portion of a blood vessel, the bendability of the distal portion of the balloon 10 is particularly important. If the distal portion of the balloon 10 cannot be inserted through the curved portion of the blood vessel, the proximal portion of the balloon 10 cannot be inserted through the curved portion, and the treatment itself using the balloon 10 cannot be performed. In this case, if the distal portion of the balloon 10 is forced through the curved portion of the blood vessel to push the balloon 10, the possibility of damaging the blood vessel increases. On the other hand, once the distal portion of the balloon 10 can be passed through the curved portion, even if the proximal portion of the distal portion of the balloon 10 has slightly less bendability than the distal portion of the balloon 10, the balloon 10 can be inserted through the curved portion while suppressing the risk of damaging the blood vessel.

[0094] The proximal section 21, intermediate section 22, and distal section 23 of the ridge 17 are determined as follows. In each ridge 17, assuming the length in the longitudinal direction from the proximal end to the distal end of the ridge 17 is L, the ridge 17 is divided into three sections with a length of L / 3: the proximal section 21, the distal section 23, and the section between the proximal and distal sections 21 and 23 as the intermediate section 22. The longitudinal position of the cutout 19 in the ridge 17, that is, whether the cutout 19 is located in the proximal section 21, intermediate section 22, or distal section 23 of the ridge 17, is determined based on the position of the bottom 19B of the cutout 19 in a cross-section along the longitudinal direction passing through the top 17A of the ridge 17. When the bottom 19B of the cutout 19 is formed to a predetermined length in the longitudinal direction, the midpoint of the bottom 19B of the cutout 19 in the longitudinal direction is defined as the position of the cutout 19 in the longitudinal direction of the ridge 17. If the bottom 19B of the cutout 19 is located exactly at the boundary between the proximal section 21 and the intermediate section 22 or the boundary between the intermediate section 22 and the distal section 23, it is determined not to belong to either section, even though it exists in both sections.

[0095] Multiple incisions 19 of varying depths may be provided in the distal section 23. Multiple incisions 19 of varying depths may also be provided in the intermediate section 22. It is sufficient that the deepest incision 19 of the incisions 19 provided in the distal section 23 of the ridge 17 is formed deeper than the deepest incision 19 of the incisions 19 provided in the intermediate section 22. In the balloon 10, it is sufficient that the incisions 19 of at least one ridge 17 are formed such that the deepest incision 19 provided in the distal section 23 is deeper than the deepest incision 19 provided in the intermediate section 22. It is preferable that incisions 19 be formed in this manner in each ridge 17. In the following description of the incisions 19, it is also preferable that incisions 19 be formed as described in at least one ridge 17, and it is more preferable that incisions 19 be formed as described in the description in each ridge 17.

[0096] When notches 19 are provided in rib 17 as described above, they must be provided in distal section 23 and intermediate section 22 of rib 17. Notches 19 may or may not be provided in proximal section 21 of rib 17. When balloon 10 is pulled back through a bend after treatment with the balloon 10, the shaft 2 of catheter 1 has already passed through the bend, making it easier to pass the balloon 10 through the bend than when the balloon 10 is pushed through the bend. Therefore, even without notches 19 in proximal section 21 of rib 17, the balloon 10 can be pulled back through the bend. However, to improve the ease of insertion into the bend even when the balloon 10 is pulled back, it is preferable to also provide notches 19 in proximal section 21 of rib 17.

[0097] Figure 11 Another example of a perspective view of the balloon 10 provided in the balloon catheter 1 is shown. Figure 11 As shown, it is also preferable to provide the incisions 19 in each section so that the deepest depth of the incision 19 provided in the distal section 23 and the deepest depth of the incision 19 provided in the proximal section 21 are deeper than the deepest depth of the incision 19 provided in the intermediate section 22. By providing the incisions 19 in the ridges 17 in this manner, it is easy to insert the balloon 10 into the curved section, whether the balloon 10 is pushed in to be inserted into the curved section or the balloon 10 is pulled back to be inserted into the curved section.

[0098] As one embodiment, multiple cutouts 19 of varying depths may be provided in the distal section 23. Providing these cutouts 19 improves the flexibility of the distal section 23 of the ridge 17, while maintaining a certain degree of rigidity in the ridge 17 even with the relatively shallow cutouts 19. This facilitates insertion of the balloon 10 into the curved portion, while maintaining the scoring function of the ridge 17 in the distal section 23.

[0099] The deepest depth of the incision 19 provided in the distal section 23 is preferably at least 1.5 times the deepest depth of the incision 19 provided in the intermediate section 22, more preferably at least 1.8 times, and even more preferably at least 2 times. This improves the flexibility of the distal section 23 of the ridge 17, and when the balloon 10 is pushed through the curved portion, the ability of the balloon 10 to follow the distal portion can be improved. On the other hand, the deepest depth of the incision 19 provided in the distal section 23 is preferably at most 10 times the deepest depth of the incision 19 provided in the intermediate section 22, more preferably at most 8 times, and even more preferably at most 5 times. This improves the flexibility of the intermediate section 22 of the ridge 17.

[0100] The distal section 23 may also be provided with the incision 19 as follows. Specifically, when the distal section 23 is bisected longitudinally and divided into a first distal section 23A and a second distal section 23B from the distal side, it is preferable to provide the incision 19 at least in the second distal section 23B. When multiple incisions 19 are provided in the distal section 23, it is preferable to provide the deepest incision 19 in the distal section 23 in the second distal section 23B. This arrangement of incisions 19 facilitates ensuring overall flexibility of the balloon 10, even for a balloon 10 that is long in the longitudinal direction. For example, the deepest incision 19 in the distal section 23 may be provided in the second distal section 23B, while a shallower incision 19 may be provided in the first distal section 23A. This ensures overall flexibility of the balloon 10, facilitating insertion of the balloon 10 into the curved portion, while also ensuring the scoring function of the ridges 17 in the distal section 23 of the ridges 17.

[0101] When the proximal section 21 of the ridge 17 is also provided with the notch 19, a plurality of notches 19 of varying depths may be provided in the proximal section 21. Providing the notches 19 in this manner improves the bendability of the proximal section 21 of the ridge 17, while ensuring the rigidity of the ridge 17 with the relatively shallow notches 19. This facilitates pulling the balloon 10 back and inserting it through the curved portion, while maintaining the scoring function of the ridge 17 in the proximal section 21 of the ridge 17.

[0102] The deepest depth of the incision 19 provided in the proximal section 21 is preferably 1.5 times or more, more preferably 1.8 times or more, and even more preferably 2 times or more of the deepest depth of the incision 19 provided in the middle section 22. Thus, the bendability of the proximal section 21 of the ridge 17 can be improved, and when the balloon 10 is pulled back and inserted into the curved portion, the tracking performance of the balloon 10 in the proximal portion can be improved. On the other hand, the deepest depth of the incision 19 provided in the proximal section 21 is preferably 10 times or less, more preferably 8 times or less, and even more preferably 5 times or less of the deepest depth of the incision 19 provided in the middle section 22. Thus, the bendability of the middle section 22 of the ridge 17 can be improved.

[0103] The proximal section 21 may also be provided with the incision 19 as follows. That is, when the proximal section 21 is divided into two equal parts in the longitudinal direction and formed from the proximal side into a first proximal section 21A and a second proximal section 21B, it is preferable to provide the incision 19 at least in the second proximal section 21B. When multiple incisions 19 are provided in the proximal section 21, it is preferable to provide the deepest incision 19 in the proximal section 21 in the second proximal section 21B. By providing the incisions 19 in this manner, it is easier to ensure the overall flexibility of the balloon 10 even for a balloon 10 that is long in the longitudinal direction. For example, the deepest incision 19 in the proximal section 21 may be provided in the second proximal section 21B, while a shallower incision 19 may be provided in the first proximal section 21A. This ensures the overall flexibility of the balloon 10, making it easier to pull the balloon 10 back and insert it into the curved portion, while also ensuring the scoring function of the ridges 17 in the proximal section 21 of the ridges 17.

[0104] The ridges 17 preferably have more cutouts 19 in the distal section 23 than in the intermediate section 22. This improves the flexibility of the distal portion of the balloon 10, making it easier to push the balloon 10 through the curved portion. Furthermore, by providing fewer cutouts 19 in the intermediate section 22 of the ridges 17, the scoring function of the intermediate section 22 of the ridges 17 can be enhanced.

[0105] When notches 19 are also provided in the proximal section 21 of the ridge 17, the notches 19 can be provided so that the number of notches 19 provided in the distal section 23 and the number of notches 19 provided in the proximal section 21 is greater than the number of notches 19 provided in the intermediate section 22. This facilitates insertion of the balloon 10 into the curved portion, whether by pushing or pulling the balloon 10. Furthermore, the scoring function of the intermediate section 22 of the ridge 17 can be enhanced.

[0106] The ridges 17 may also be provided with cutouts 19 at approximately equal intervals in the longitudinal direction. Even with such a configuration, the deep cutouts 19 provided in the distal section 23 facilitate pushing the balloon 10 in and inserting it through the curved portion. Furthermore, the deep cutouts 19 provided in the proximal section 21 facilitate pulling the balloon 10 back and inserting it through the curved portion.

[0107] Although the ridge 17 includes multiple cutouts 19, the lengths of the multiple cutouts 19 in the longitudinal direction of the ridge 17 may be the same or different. For example, the maximum longitudinal length of the cutout 19 provided in the distal section 23 may be longer than the maximum longitudinal length of the cutout 19 provided in the intermediate section 22. Alternatively, the longitudinal length of the deepest cutout 19 provided in the distal section 23 may be longer than the longitudinal length of the deepest cutout 19 provided in the intermediate section 22. Forming the cutouts 19 in this manner in the ridge 17 allows the balloon 10 to bend more significantly in the distal section 23 of the ridge 17. Furthermore, the scoring function of the ridge 17 is enhanced in the intermediate section 22.

[0108] In the above case, the maximum length of the long axis direction of the incision 19 provided in the distal section 23 is preferably 1.5 times or more, more preferably 1.8 times or more, even more preferably 2 times or more, and further preferably 10 times or less, more preferably 8 times or less, and further preferably 5 times or less of the maximum length of the long axis direction of the incision 19 provided in the intermediate section 22. Alternatively, the length of the long axis direction of the deepest incision 19 provided in the distal section 23 is preferably 1.5 times or more, more preferably 1.8 times or more, even more preferably 2 times or more, and further preferably 10 times or less, more preferably 8 times or less, and further preferably 5 times or less of the length of the deepest incision 19 provided in the intermediate section 22.

[0109] When the notches 19 are also provided in the proximal section 21 of the ridge 17, the maximum length of the notches 19 provided in the proximal section 21 in the longitudinal direction may be formed to be longer than the maximum length of the notches 19 provided in the intermediate section 22 in the longitudinal direction. Alternatively, the length of the deepest notches 19 provided in the proximal section 21 in the longitudinal direction may be formed to be longer than the length of the deepest notches 19 provided in the intermediate section 22 in the longitudinal direction. By forming the notches 19 in the ridge 17 in this manner, the balloon 10 can be bent more greatly in the proximal section 21 of the ridge 17.

[0110] In the above case, the maximum length of the long axis direction of the incision 19 provided in the proximal section 21 is preferably 1.5 times or more, more preferably 1.8 times or more, further preferably 2 times or more, and further preferably 10 times or less, more preferably 8 times or less, and further preferably 5 times or less of the maximum length of the long axis direction of the incision 19 provided in the intermediate section 22. Alternatively, the length of the long axis direction of the deepest incision 19 provided in the proximal section 21 is preferably 1.5 times or more, more preferably 1.8 times or more, further preferably 2 times or more, and further preferably 10 times or less, more preferably 8 times or less, and further preferably 5 times or less of the length of the long axis direction of the deepest incision 19 provided in the intermediate section 22.

[0111] The length of the straight tube portion 13 of the balloon 10 in the longitudinal direction may be, for example, 4 mm or more, 10 mm or more, 20 mm or more, or 30 mm or more. However, for a balloon 10 provided with ridges 17, a longer longitudinal length makes it more difficult to insert the balloon through the curved portion. Therefore, to more effectively utilize the effect of providing the notches 19 in the ridges 17, the length of the straight tube portion 13 of the balloon 10 in the longitudinal direction is preferably 50 mm or more, more preferably 60 mm or more, and even more preferably 80 mm or more.

[0112] like Figure 12As shown, in a vertical cross-section of the straight tube portion 13 along the longitudinal axis, the ridge 17 may be formed so that its width gradually narrows from the base 17B toward the top 17A, with the cutout 19 formed only in the portion of the stepped ridge 17 on the top 17A side. For example, the ridge 17 may include a first-stage portion 26 adjacent to the outer surface of the balloon body 16 and a second-stage portion 27 closer to the top 17A, with the cutout 19 formed in the second-stage portion 27 and not in the first-stage portion 26. Alternatively, a deep cutout 19 may extend from the second-stage portion 27 to the first-stage portion 26, while a shallow cutout 19 may be formed in the second-stage portion 27 and not in the first-stage portion 26. The first-stage portion 26 and the second-stage portion 27 may be made of the same material or different materials. For example, both the first-stage portion 26 and the second-stage portion 27 may be made of resin, or the first-stage portion 26 may be made of metal and the second-stage portion 27 may be made of resin.

[0113] The outer surface of the straight tube portion 13 of the balloon 10 may also be provided with a drug. The drug is not particularly limited as long as it is a pharmacologically active substance. For example, gene therapy drugs, non-gene therapy drugs, small molecules, cells, and other drugs that are permitted as medicines may be mentioned. In particular, when a catheter is used for the purpose of inhibiting restenosis of a blood vessel after treatment during angioplasty, it is preferred to use an anti-restenosis agent such as an antiproliferative agent or an immunosuppressant as the drug. Examples of such drugs include paclitaxel, sirolimus (rapamycin), everolimus, and zotarolimus.

[0114] This application claims the benefit of priority based on Japanese Patent Application No. 2023-065587, filed on April 13, 2023. The entire contents of the specification of Japanese Patent Application No. 2023-065587, filed on April 13, 2023, are incorporated herein by reference.

[0115] Description of Reference Numerals

[0116] 1…Balloon catheter; 2…Shaft; 3…Inner shaft; 4…Outer shaft; 4A…Proximal outer shaft; 4B…Distal outer shaft; 5…Hub; 6…Fluid injection port; 7…Guidewire port; 8…Tip; 9…Radiopaque marker; 10…Balloon; 11…Proximal sleeve; 12…Proximal tapered portion; 13…Straight tube; 14…Distal tapered portion; 15…Distal sleeve; 16…Balloon body; 17…Ribbon; 17A…Top; 17B…Base; 18… rib segment; 19… incision; 19A… top; 19B… bottom; 19P… proximal end; 19D… distal end; 20… discontinuity; 21… proximal interval; 21A… first proximal interval; 21B… second proximal interval; 22… middle interval; 23… distal interval; 23A… first distal interval; 23B… second distal interval; 24… rib presence region; 25… rib non-presence region; 26… first-level portion; 27… second-level portion.

Claims

1. A balloon for a balloon catheter, having a long axis extending from a proximal side to a distal side, a radial direction perpendicular to the long axis, and a circumferential direction, characterized in that: The balloon comprises: a straight tube portion; a proximal tapered portion located closer to the proximal side than the straight tube portion; and a distal tapered portion located farther from the proximal side than the straight tube portion. The straight tube portion comprises: a cylindrical balloon body portion; and a convex strip protruding radially outward from the outer surface of the balloon body portion and extending in the longitudinal direction. The convex strip is formed with a plurality of cutouts arranged along the long axis direction. When the convex strip is divided into three equal parts along the long axis direction into a proximal section, a middle section, and a distal section, at least the distal section and the middle section are provided with the cutout. The deepest depth of the incision provided in the distal section is deeper than the deepest depth of the incision provided in the intermediate section.

2. The balloon according to claim 1, wherein The incisions are respectively provided in the proximal section, the middle section and the distal section. The deepest depth of the incision provided in the distal section and the deepest depth of the incision provided in the proximal section are deeper than the deepest depth of the incision provided in the intermediate section.

3. The balloon according to claim 1, wherein The number of the incisions provided in the distal section is greater than the number of the incisions provided in the intermediate section.

4. The balloon according to claim 2, characterized in that The number of the incisions provided in the distal section and the number of the incisions provided in the proximal section are greater than the number of the incisions provided in the intermediate section.

5. The balloon according to claim 1, wherein A plurality of the incisions having different depths are provided in the distal section.

6. The balloon according to claim 2, characterized in that A plurality of the incisions having different depths are respectively provided in the proximal section and the distal section.

7. The balloon according to claim 1, characterized in that The ridges are made of resin, metal, or a combination thereof.

8. The balloon according to claim 2, characterized in that The ridges are made of resin, metal, or a combination thereof.

9. The balloon according to claim 1, wherein The length of the straight tube portion in the longitudinal direction is 50 mm or more.

10. The balloon according to claim 2, characterized in that The length of the straight tube portion in the longitudinal direction is 50 mm or more.

11. A balloon catheter, characterized in that: A balloon according to any one of claims 1 to 10 is provided.

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