Balloon body for catheter and balloon catheter

Abstract

The balloon (3) has rigid portions (30A) including at least a joint portion where the hard member (6) is provided, and flexible portions (30B) disposed between the rigid portions (30A) in the circumferential direction and softer than the rigid portions (30A). The balloon (3) deforms in such a manner that the hard member (6) moves in a direction away from the reference axis (C1) when switching from the contracted state to the expanded state, and the hard member (6) moves in a direction approaching the reference axis (C1) when switching from the expanded state to the contracted state. At least a portion of the hard member (6) is disposed in an imaginary closed region (S1) formed by joining the circumferential end of each of the rigid portions (30A) and the circumferential end of the other rigid portion (30A), and the reference axis (C1) is disposed at the center of the imaginary closed region (S1).

Description

TECHNICAL FIELD

[0001] The present application relates to a balloon body for a catheter and a balloon catheter. BACKGROUND

[0002] In order to make the passage of a balloon catheter in a blood vessel good, it is desirable that the diameter of the balloon in a contracted state be small. Therefore, a technique for reducing the diameter of a balloon in a contracted state has been proposed (for example, refer to Patent Literature 1).

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent No. 5466008 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] There is a balloon catheter in which a hard member for acting on a lesion portion in a blood vessel is provided to a balloon. In such a balloon catheter, there is a case where the hard member is stretched outward at the time of contraction of the balloon, thereby becoming an obstacle to miniaturization of the diameter.

[0008] An object of the present application is to provide a balloon body for a catheter and a balloon catheter provided with the same, which can miniaturize the diameter at the time of contraction even in the case where a hard member is provided.

[0009] SOLUTION TO THE PROBLEM

[0010] The catheter balloon body of the first aspect of the present application has: a balloon that can be deformed into a contracted state and an inflated state; and a plurality of rigid members that are located on the side of the balloon and project outward, the catheter balloon body being characterized in that the balloon has: a plurality of rigid portions that include at least a connection portion for each of the plurality of rigid members; and a plurality of flexible portions that are arranged between the plurality of rigid portions in the circumferential direction and are softer than the plurality of rigid portions, the balloon being deformed in such a manner that each of the plurality of rigid members moves in a direction away from a prescribed reference axis when switching from the contracted state to the inflated state, and the balloon being deformed in such a manner that each of the plurality of rigid members moves in a direction approaching the reference axis when switching from the inflated state to the contracted state, the plurality of rigid members being harder than the plurality of flexible portions of the balloon, at least a portion of each of the portions of the plurality of rigid members of the balloon in the contracted state that project outward from the balloon is arranged in an imaginary closed region in a cross section orthogonal to the reference axis, the imaginary closed region is a region formed when connecting an end portion of the circumferential direction of each of the plurality of rigid portions and an end portion of the circumferential direction of another rigid portion adjacent in the circumferential direction, and the reference axis is arranged at the center of the imaginary closed region.

[0011] In the catheter balloon body of the first aspect, the diameter in the contracted state can be made smaller than the diameter in a state in which the plurality of rigid members are arranged along the imaginary closed region. Therefore, the catheter balloon body can be downsized in the contracted state even when the balloon is provided with the plurality of rigid members.

[0012] In the first aspect, the reference axis can be arranged at any one of the center of gravity, the incenter, the circumcenter, and the orthocenter of the imaginary closed region. In this case, the catheter balloon body can be downsized uniformly in the circumferential direction.

[0013] In the first aspect, the shape of the cross section of the balloon in the inflated state that is orthogonal to the reference axis can be substantially circular, and the reference axis can be arranged at a position at which the distance from each portion of the balloon in the inflated state is equal. In this case, the catheter balloon body can minimize the diameter by uniformly contracting the balloon in the circumferential direction when deforming from the inflated state to the contracted state.

[0014] In the first aspect, the end portion of each of the plurality of rigid portions can contact a portion other than the end portion of the other rigid portion adjacent in the circumferential direction when the balloon is in the contracted state. In this case, the catheter balloon body can easily form a state in which at least a portion of each of the plurality of rigid members is arranged in the imaginary closed region when the balloon is set to the contracted state.

[0015] In the first aspect, it can also be that, when the balloon is in the contracted state, the ends of each of the plurality of rigid portions contact the link portions included by the other rigid portion adjacent in the circumferential direction. In this case, the catheter balloon body can further easily form a state in which at least a portion of each of the plurality of rigid members is disposed within the imaginary closed region when the balloon is in the contracted state.

[0016] In the first aspect, it can also be that, when the balloon is in the contracted state, each of the plurality of flexible portions covers the plurality of rigid members from a side opposite to a side close to the reference axis. In this case, the catheter balloon body can suppress the plurality of rigid members from being hooked in the blood vessel in the contracted state by the plurality of flexible portions. Thus, the catheter balloon body can improve the passability in the blood vessel.

[0017] In the first aspect, it can also be that, in a cross section orthogonal to the reference axis, all of the plurality of rigid members are disposed within the imaginary closed region. In this case, the catheter balloon body can minimize the diameter in the contracted state.

[0018] In the first aspect, it can also be that, when the balloon is in the contracted state, the shortest distance between the plurality of rigid members and the reference axis is shorter than the shortest distance between the midpoint of the circumferential direction of the plurality of link portions and the reference axis. In this case, the catheter balloon body can easily form a state in which at least a portion of each of the plurality of rigid members is disposed within the imaginary closed region when the balloon is in the contracted state.

[0019] In the first aspect, it can also be that the length of the circumferential direction of the rigid portion and the link portion is equal, and the rigid member, the rigid portion, and the link portion are the same material. In this case, the catheter balloon body having the rigid member, the rigid portion, and the flexible portion can be easily manufactured.

[0020] The balloon catheter of the second aspect of the present application is characterized by including: the catheter balloon body of the first aspect; and an elongated member extending along the reference axis and inserted through the balloon, each of the plurality of rigid portions being in contact with the elongated member when the balloon is in the contracted state. According to the second aspect, the balloon catheter can minimize the diameter of the catheter balloon body in the contracted state. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a view showing a balloon catheter 1A including a balloon 3 in an inflated state.

[0022] Figure 2 is a partially enlarged view of a boundary portion between a rigid portion 30A and a flexible portion 30B.

[0023] Figure 3 is a view showing a balloon catheter 1A including a balloon 3 in a contracted state.

[0024] Figure 4 is a view showing a balloon body 10A including a balloon 3 in a contracted state.

[0025] Figure 5 is a view showing a balloon body 10A including a balloon 3 provided with a rigid portion 30A along an imaginary closed region SI.

[0026] Figure 6 is a view showing a case where the balloon body 10A changes to an expanded state and a contracted state.

[0027] Figure 7 is a view showing a balloon catheter IB including a balloon 4 in an expanded state.

[0028] Figure 8 is a view showing a balloon catheter IB including a balloon 4 in a contracted state.

[0029] Figure 9 is a view showing a balloon body 10B including a balloon 4 in a contracted state.

[0030] Figure 10 is a view showing a balloon body 10B including a balloon 4 provided with a rigid portion 40A along an imaginary closed region S2.

[0031] Figure 11 is a view showing a case where the balloon body 10B changes to an expanded state and a contracted state.

[0032] Figure 12 is a view showing centers K3 to K6 of the imaginary closed regions S3.

[0033] Figure 13 is a view showing a modification of the balloon catheter 1A including a balloon 3 in a contracted state.

[0034] Figure 14 is a view showing various embodiments of the balloon 3 in a contracted state. DETAILED DESCRIPTION

[0035] An embodiment of a balloon catheter 1 (1A, IB) of the present application will be described with reference to the drawings. The drawings referred to are used for explaining the technical features employed in the present application. The structure and the like of the device described are not intended to limit the present application to them alone, but are mere illustrative examples. The balloon catheter 1 can dilate a stenotic lesion formed in a blood vessel, or cause the hard member 6 (first embodiment), 7 (second embodiment) described later to act on the lesion to crush or cut it.

[0036] <First Embodiment (Balloon Catheter 1A)>

[0037] Reference Figures 1-6 The balloon catheter 1A of the first embodiment will be described. The balloon catheter 1A has a catheter shaft 2 and a balloon body 10A.

[0038] <Catheter axis 2>

[0039] like Figure 1 , Figure 3 As shown, the balloon body 10A is connected to one end of the tubular catheter shaft 2. The balloon catheter 1A is used with a catheter hub (not shown) connected to the other end of the catheter shaft 2. The catheter hub can supply compressed fluid to the balloon 3 (described later) of the balloon body 10A via the catheter shaft 2.

[0040] One of the two ends of catheter shaft 2 is called the "front end side". The other end of catheter shaft 2 is called the "base end side". The direction extending along catheter shaft 2 is called the "extension direction". The axis that passes through the center of catheter shaft 2 and extends along the extension direction is called the reference axis C1. In the cross section (simply referred to as the "section") in the case of cutting in a plane orthogonal to the reference axis C1, the side closer to the reference axis C1 in the radial direction centered on the reference axis C1 is called the "inner side", and the side away from the reference axis C1 in the radial direction centered on the reference axis C1 is called the "outer side".

[0041] The conduit shaft 2 has an outer tube 21 and an inner tube 22. Both the outer tube 21 and the inner tube 22 are flexible. The inner diameter of the outer tube 21 is larger than the outer diameter of the inner tube 22. The inner tube 22, except for a predetermined portion on its front end, is disposed within the lumen of the outer tube 21. A predetermined portion on the front end of the inner tube 22 protrudes from the end of the outer tube 21 on its front end (referred to as "front end 211") toward the front end. The end of the inner tube 22 on its front end (referred to as "front end 221") is positioned further forward than the front end 211 of the outer tube 21. The predetermined portion on the front end of the inner tube 22 is referred to as "protrusion 225". The materials of the outer tube 21 and the inner tube 22 are not particularly limited. As an example of the materials for the outer tube 21 and the inner tube 22, a polyamide resin is used.

[0042] Compressed fluid supplied from the catheter tip flows through the space outside the inner cavity of the inner tube 22, which is located within the inner cavity of the outer tube 21. A guidewire (not shown) is inserted into the inner cavity of the inner tube 22.

[0043] <Bag 10A>

[0044] The balloon body 10A has a balloon 3 and a rigid member 6. The balloon 3 is deformable between a contracted state and an expanded state according to the presence or absence of supply of compressed fluid by a catheter head not shown. Figure 1 The balloon 3 is shown in the expanded state, Figure 3 The balloon 3 is shown in the contracted state. The rigid member 6 is fixed to the balloon 3.

[0045] <balloon 3>

[0046] The end portion on the front end side of the balloon 3 (referred to as "front end 3D") is connected to the vicinity of the front end 221 in the protruding portion 225 of the inner side tube 22 by heat fusion. In addition, the end portion on the base end side of the balloon 3 (referred to as "base end 3P") is connected to the vicinity of the front end 211 of the outer side tube 21 by heat fusion. The balloon 3 covers the protruding portion 225 of the inner side tube 22 from the outside. The material of the balloon 3 is not particularly limited. As an example of the material of the balloon 3, a polyamide-based resin is used. As shown in Figure 1 The cross-sectional shape of the balloon 3 in the expanded state is substantially circular with the reference axis Cl as the center. That is, the reference axis Cl is disposed at a position at which the distance from each portion of the balloon 3 is equal. Note that, in Figure 1 , for ease of explanation, it is shown in a manner that the distance between each of the rigid portion 30A and the flexible portion 30B and the reference axis Cl is slightly different. However, the difference amount between the distance between the reference axis Cl and the rigid portion 30A and the distance between the reference axis Cl and the flexible portion 30B is very small compared to each distance. Therefore, in essence, the reference axis Cl is disposed at a position at which the distance from each portion of the balloon 3 including the rigid portion 30A and the flexible portion 30B is equal.

[0047] As shown in Figure 1 In the balloon 3, a front end side tapered region 3A, an expanded region 3B, and a base end side tapered region 3C are defined. The front end side tapered region 3A is a region in the balloon 3 in the expanded state that extends while expanding in diameter from the front end 3D toward the base end 3P. The base end side tapered region 3C is a region in the balloon 3 in the expanded state that extends while expanding in diameter from the base end 3P toward the front end 3D. The expanded region 3B is a region in the balloon 3 in the expanded state that is sandwiched between the front end side tapered region 3A and the base end side tapered region 3C and has substantially the same diameter in the extending direction. The side surface of the expanded region 3B of the balloon 3 is referred to as "side surface 30".

[0048] The expansion region 3B of the balloon 3 has rigid portions 31A, 32A, 33A, and 34A (collectively referred to as "rigid portion 30A") and flexible portions 31B, 32B, 33B, and 34B (collectively referred to as "flexible portion 30B"). The rigid portions 30A and flexible portions 30B are arranged sequentially along the circumferential direction E1 in the order of rigid portion 31A, flexible portion 31B, rigid portion 32A, flexible portion 32B, rigid portion 33A, flexible portion 33B, rigid portion 34A, and flexible portion 34B. The rigid portions 30A and flexible portions 30B are arranged alternately along the circumferential direction E1. The rigid portions 31A, 32A, 33A, and 34A are equally spaced along the circumferential direction E1. The circumferential direction E1 corresponds to a direction orthogonal to the reference axis C1 in the direction extending along the expansion region 3B of the balloon 3.

[0049] The rigid portion 30A and the flexible portion 30B have different thicknesses. Correspondingly, their hardness also differs. The flexible portion 30B is thinner than the rigid portion 30A, therefore the flexible portion 30B is softer than the rigid portion 30A. It should be noted that the difference in hardness between the rigid portion 30A and the flexible portion 30B can be determined by the results of at least one of various known hardness tests.

[0050] The rigid portion 30A is formed by applying an adhesive to bond the rigid component 6, which will be described later. That is, the rigid portion 30A and the flexible portion 30B are made of different materials. Furthermore, the thickness of the rigid portion 30A is greater than the thickness of the adhesive than the thickness of the flexible portion 30B. Additionally, due to the application of adhesive, the rigid portion 30A is harder than the flexible portion 30B.

[0051] The hardness of the rigid portion 30A gradually softens towards the two ends in the circumferential direction. The hardness of the flexible portion 30B gradually hardens towards the two ends in the circumferential direction. The circumferential change in the hardness of the balloon 3 is gradual between the rigid portion 30A and the flexible portion 30B. No abrupt change in hardness occurs at the boundary between the rigid portion 30A and the flexible portion 30B. Therefore, as... Figure 2 As shown, when the balloon 3 is inflated, the two ends of the rigid part 30A bend circumferentially, and no step is formed at the boundary between the rigid part 30A and the flexible part 30B. It should be noted that, for the sake of simplicity, in... Figure 2 In the accompanying drawings, the rigid part 30A is not depicted as curved but as planar.

[0052] like Figure 1As shown, the flexible portion 30B is curved along an arc centered on the reference axis C1 when the balloon 3 is in the inflated state. The lengths of the circumferential direction E1 of the rigid portions 31A to 34A are the same. The lengths of the circumferential direction E1 of the flexible portions 31B to 34B are the same. The length of the circumferential direction E1 of the rigid portion 30A is shorter than the length of the circumferential direction E1 of the flexible portion 30B. In addition, the length of the circumferential direction E1 of the rigid portion 30A is greater than the diameter of the inner tube 22.

[0053] <Hard member 6>

[0054] The hard members 61A, 62A, 63A, 64A (collectively referred to as "hard members 6") are provided on the side surface 30 of the balloon 3. The hard members 6 each have a shape of a triangular prism and extend in the extending direction. The hard members 61A, 62A, 63A, 64A are fixed to the rigid portions 31A, 32A, 33A, 34A of the balloon 3, respectively. The hard members 6 protrude outward with respect to the balloon 3. A side surface of the hard members 6 that is close to the reference axis C1 in the inflated state is referred to as "side surface 601". A portion of the rigid portion 30A of the balloon 3 that is in contact with the side surface 601 of the hard member 6 is referred to as "joint portion 301".

[0055] The length of the circumferential direction E1 of the side surface 601 of the hard member 6 is shorter than the length of the circumferential direction E1 of the rigid portion 30A to which the hard member 6 is joined. The both end portions of the circumferential direction E1 of the rigid portion 30A protrude to both sides of the circumferential direction E1 with respect to the hard member 6 fixed to the rigid portion 30A. Portions of the rigid portion 30A corresponding to the end portion on one side of the circumferential direction E1 and the end portion on the other side of the circumferential direction E1 in the case where the balloon 3 is in the inflated state are referred to as "end portion 311", "end portion 312", respectively. The end portions 311, 312 are collectively referred to as "end portion 310". For example, the end portion 311 of the rigid portion 31A and the end portion 312 of the rigid portion 32A are each joined to the flexible portion 31B. The end portion 311 of the rigid portion 32A and the end portion 312 of the rigid portion 33A are each joined to the flexible portion 32B. The end portion 311 of the rigid portion 33A and the end portion 312 of the rigid portion 34A are each joined to the flexible portion 33B. The end portion 311 of the rigid portion 34A and the end portion 312 of the rigid portion 31A are each joined to the flexible portion 34B.

[0056] A vertex at which the two side surfaces 602 other than the side surface 601 of the hard member 6 intersect is referred to as "vertex 600". A direction that extends orthogonally to the side surface 601 and extends from the side surface 601 through the vertex 600 is referred to as "protruding direction Y1". In the inflated state, the protruding direction Y1 is directed outward in the radial direction.

[0057] The rigid member 6 is harder than the flexible portion 30B of the balloon 3. It should be noted that the difference in hardness between the rigid member 6 and the flexible portion 30B can be determined by the results of at least one of various known hardness tests. There is no limitation on the relative hardness of the rigid member 6 and the rigid portion 30A of the balloon 3. The hardness of the rigid member 6 can be harder or softer than the hardness of the rigid portion 30A. The hardness of the rigid member 6 and the rigid portion 30A can also be the same. The material of the rigid member 6 is not particularly limited. Metal is used as an example of the material of the rigid member 6. That is, in the balloon body 10A, the rigid member 6, made of a material different from that of the balloon 3, is formed by fixing it to the side 30 of the rigid portion 30A. The rigid member 6 can also be made of the same material as the balloon 3.

[0058] <Balloon 3 contraction / inflation>

[0059] like Figure 3 As shown, the retracted balloon 3 has blades 31C, 32C, 33C, and 34C (collectively referred to as "blades 30C"). Blades 31C, 32C, 33C, and 34C are formed by folding the flexible portions 31B, 32B, 33B, and 34B of the balloon 3 and wrapping them around the rigid members 61A, 62A, 63A, and 64A from the outside, respectively. The outer portion of the rigid member 6, opposite to the side closest to the reference axis C1, is covered by blades 30C. Blades 30C are also referred to as "wings" or "wings".

[0060] In the balloon 3 in the contracted state, the rigid portions 30A are in contact with the inner side tube 22 of the catheter shaft 2. In addition, the end portion 311 of the rigid portion 31A of the balloon 3 is proximate to a portion other than the end portion 310 of the face on the side opposite the face of the fixed rigid member 62A in the rigid portion 32A. More specifically, the end portion 311 of the rigid portion 31A is proximate to the linking portion 301 of the fixed rigid member 62A in the rigid portion 32A from the side opposite the side of the fixed rigid member 62A. Note that, although detailed description is omitted, the positional relationship of the end portion 311 of the rigid portion 32A of the balloon 3 and the rigid portion 33A, the positional relationship of the end portion 311 of the rigid portion 33A of the balloon 3 and the rigid portion 34A, and the positional relationship of the end portion 311 of the rigid portion 34A of the balloon 3 and the rigid portion 31A are also the same. That is, the end portion 311 of each of the rigid portions 30A is proximate to a portion other than the end portion 311, 312 of the other rigid portion 30A adjacent on one side in the circumferential direction E1, more specifically, the linking portion 301 of the other rigid portion 30A adjacent on one side in the circumferential direction E1. Note that, the end portion 311 of the rigid portion 31A of the balloon 3 can also be in contact with a portion other than the end portion 310 of the face on the side opposite the face of the fixed rigid member 62A in the rigid portion 32A. More specifically, the end portion 311 of the rigid portion 31A can also be in contact with the linking portion 301 of the fixed rigid member 62A in the rigid portion 32A from the side opposite the side of the fixed rigid member 62A. The same applies to the rigid portions 32A to 34A of the balloon 3.

[0061] As shown in Figure 4 , in the cross section of the balloon 3 in the contracted state, the balloon body 10A, a virtual closed region S1 is defined. The virtual closed region S1 is a region surrounded by the cross sections of the rigid portions 30A (rigid portions 31A to 34A) in a case where the end portion 311 of the rigid portion 30A and the end portion 312 of the other rigid portion 30A adjacent on one side in the circumferential direction E1 when the balloon 3 is in the expanded state are linked (see Figure 5 ).

[0062] Note that, the angle formed by the rigid portion 30A and the other rigid portion 30A in the linking portion T1 in which the end portions 311, 312 are linked is the same in all of the linking portions T1 included in the virtual closed region S1. For example, in the case of the balloon body 10A, four rigid portions 30A (rigid portions 31A to 34A) are included, and thus the shape of the virtual closed region S1 becomes a square with the line segments represented by the cross sections of the rigid portions 31A to 34A as the respective sides. In addition, the angle formed by the rigid portion 30A and the other rigid portion 30A in each of the four corners (four linking portions T1) of the virtual closed region S1 is 90°.

[0063] Furthermore, the imaginary closed region S1 is defined such that its center K1 is aligned with the reference axis C1. It should be noted that the center K1 of the imaginary closed region S1 corresponds to its centroid. Moreover, the imaginary closed region S1 is defined such that all its edges are parallel to any one of the rigid parts 30A.

[0064] With the hypothetical closed region S1 defined as described above, in the cross-section of the balloon body 10A, a portion of each of the rigid members 61A to 64A is disposed within the hypothetical closed region S1. In the cross-section, a circumcircle U11 is defined that is in contact with the blade 30C of the balloon 3 in the contracted state and centered on the reference axis C1. The radius of the circumcircle U11 is denoted as R11.

[0065] Figure 5 Example of the actual contraction state of balloon 3 (refer to) Figure 4 Different contraction states. Figure 5 In this configuration, end 312 of rigid portion 32A contacts end 311 of rigid portion 31A, end 312 of rigid portion 33A contacts end 311 of rigid portion 32A, end 312 of rigid portion 34A contacts end 311 of rigid portion 33A, and end 312 of rigid portion 31A contacts end 311 of rigid portion 34A. That is, in Figure 5 In the middle, line segments represented by the cross sections of the rigid parts 31A to 34A are arranged at the positions of each side of the imaginary closed region S1.

[0066] In such Figure 5 With the rigid part 30A arranged as shown, in the cross-section of the balloon body 10A, rigid members 61A to 64A are respectively arranged outside the imaginary closed region S1. In the cross-section, a circumcircle U12 is defined that is connected to the blade 30C of the balloon 3 and centered on the reference axis C1. The radius of the circumcircle U12 is denoted as R12. The radius R12 is greater than... Figure 4 The radius R11 in the middle is large. That is, by using the rigid part 30A of the balloon 3 in the contracted state as... Figure 4 As shown, the balloon 3 is configured such that its diameter is greater than that of the balloon itself. Figure 5 The situation shown is small.

[0067] Figure 6 This shows the deformation of balloon 3 of balloon body 10A between the contracted and inflated states. The catheter tip (not shown) is also depicted. Figure 6 The balloon 3, in its contracted state as shown in (A), is supplied with compressed fluid. In this case, as... Figure 6 As shown in (B), the flexible parts 31B to 34B of the sac 3 are elongated, and the blades 31C to 34C (refer to) Figure 6The rigid members 61A to 64A are moved in the radial direction toward the outside, respectively. The rigid members 61A to 64A are moved away from the reference axis C1, respectively.

[0068] In a case where the compressed fluid is further supplied to the balloon 3, the rigid members 61A to 64A are further moved in directions away from the reference axis C1 while rotating to change the direction Y1 of protrusion (refer to Figure 1 ) toward the outside. As a result, as shown in (C) of Figure 6 , the balloon 3 becomes in the inflated state.

[0069] On the other hand, the compressed fluid is removed from the balloon 3 in the inflated state shown in (C) of Figure 6 . In this case, as shown in (B) of Figure 6 , the flexible portions 31B to 34B of the balloon 3 are folded. In addition, the rigid members 61A to 64A are moved in the radial direction toward the inside with respect to the positions in the inflated state (refer to Figure 6 (C)). At this time, the rigid members 61A to 64A are moved in directions approaching the reference axis C1, respectively.

[0070] In a case where the compressed fluid is further removed from the balloon 3, the rigid members 61A, 62A, 63A, and 64A are further moved in directions approaching the reference axis C1, respectively. In addition, the flexible portions 31B to 34B of the balloon 3 are wound around the rigid members 61A to 64A in the folded state, and the vanes 31C to 34C are formed. As a result, as shown in (A) of Figure 6 , the balloon 3 becomes in the contracted state.

[0071] Note that the balloon 3 has a tendency to become in the configuration shown in (A) of Figure 6 when changing from the inflated state to the contracted state.

[0072] <Effects of the First Embodiment>

[0073] In the balloon catheter 1A, the radius R11 of the balloon body 10A in a case where the balloon 3 is set to the contracted state (refer to Figure 4 ) can be made smaller than the radius R12 of the balloon body 10A in a state where the rigid portion 30A is arranged along the imaginary closed region S1 (refer to Figures 7-11 ). Therefore, the balloon catheter 1A can miniaturize the diameter in the contracted state even in a case where the balloon 3 is provided with the rigid members 6.

[0074] The center K1 corresponding to the center of gravity of the imaginary closed region S1 is arranged at a position coinciding with the reference axis C1. In this case, the balloon catheter 1A can miniaturize the diameter of the balloon body 10A uniformly in the circumferential direction E1.

[0075] In the balloon 3 in the inflated state, the shape of the cross section orthogonal to the reference axis CI is substantially circular, and the reference axis CI is disposed at a position at which the distance from each portion of the balloon 3 is equal. In this case, the balloon catheter 1A can minimize the diameter of the balloon body 10A by uniformly contracting the balloon 3 in the circumferential direction El when the balloon 3 in the inflated state is set to the contracted state in which the cross section is substantially circular.

[0076] When the balloon 3 is in the contracted state, the end portion 311 of each of the rigid portions 30A approaches a portion other than the end portions 311 and 312 of the other rigid portion 30A adjacent on one side in the circumferential direction El, more specifically, the joint portion 301 of the other rigid portion 30A. In this case, the balloon catheter 1A can easily form a state in which a portion of the rigid member 6 is disposed within the virtual closed region SI when the balloon 3 is set to the contracted state.

[0077] When the balloon 3 is in the contracted state, the flexible portion 30B covers the side of the rigid member 6 opposite to the side approaching the reference axis CI. In this case, the balloon catheter 1A can suppress the case where the rigid member 6 in the contracted state is hooked in the blood vessel using the flexible portion 30B. Therefore, the balloon catheter 1A can make the passability of the balloon body 10A in the blood vessel good.

[0078] [Second Embodiment (Balloon Catheter 1B)]

[0079] Reference Figure 1 The balloon catheter 1B of the second embodiment will be described. The balloon catheter 1B has a catheter shaft 2 and a balloon body 10B. The structure of the catheter shaft 2 is the same as that of the catheter shaft 2 of the balloon catheter 1A of the first embodiment (see Figure 3 , Figure 7 ), and thus the description is omitted. As for other structures common to the first embodiment, the description is simplified.

[0080] [Balloon Body 10B]

[0081] The balloon body 10B has a balloon 4 and a rigid member 7. The balloon 4 corresponds to the balloon 3 of the first embodiment. Figure 8 The balloon 4 in the inflated state is shown, Figure 7 The balloon 4 in the contracted state is shown.

[0082] [Balloon 4]

[0083] Figure 8The leading end 4D, the base end 4P, the leading end side tapered region 4A, the inflation region 4B, the base end side tapered region 4C, and the side surface 40 of the balloon 4 correspond to the leading end 3D, the base end 3P, the leading end side tapered region 3A, the inflation region 3B, the base end side tapered region 3C, and the side surface 30 of the balloon 3 of the first embodiment, respectively. The cross-sectional shape of the balloon 4 in the inflated state is a substantially circular shape with the reference axis C2 as the center. That is, the reference axis C2 is disposed at a position at which the distance from each portion of the balloon 4 is equal.

[0084] The inflation region 4B of the balloon 4 has rigid portions 41A, 42A, 43A, 44A, 45A, 46A (collectively referred to as "rigid portions 40A") and flexible portions 41B, 42B, 43B, 44B, 45B, 46B (collectively referred to as "flexible portions 40B"). The rigid portions 40A and the flexible portions 40B are arranged in order of the rigid portion 41A, the flexible portion 41B, the rigid portion 42A, the flexible portion 42B, the rigid portion 43A, the flexible portion 43B, the rigid portion 44A, the flexible portion 44B, the rigid portion 45A, the flexible portion 45B, the rigid portion 46A, and the flexible portion 46B along the circumferential direction E2. The rigid portions 40A and the flexible portions 40B are alternately arranged along the circumferential direction E2. The rigid portions 41A, 42A, 43A, 44A, 45A, 46A are disposed at equal intervals in the circumferential direction E2.

[0085] In the rigid portions 40A and the flexible portions 40B, the thicknesses are different. In the rigid portions 40A and the flexible portions 40B, the hardnesses also differ in correspondence with the differences in the thicknesses. The flexible portions 40B are thinner than the rigid portions 40A, and thus the flexible portions 40B are softer than the rigid portions 40A. The flexible portions 40B bend along a circular arc with the reference axis C2 as the center when the balloon 4 is in the inflated state. The length of the circumferential direction E2 of the rigid portion 40A is shorter than the length of the circumferential direction E2 of the flexible portion 40B. The length of the circumferential direction E2 of the rigid portion 40A is greater than the diameter of the inner side tube 22. The characteristics of the other rigid portions 40A and the flexible portions 40B are in accordance with the rigid portions 30A and the flexible portions 30B of the first embodiment.

[0086] <Hard member 7>

[0087] The hard members 71A, 72A, 73A, 74A, 75A, 76A (collectively referred to as "hard members 7") are fixed to the side surface 40 of the balloon 4. The shape of the hard members 7 is the same as that of the hard members 6 of the first embodiment. The hard members 71A, 72A, 73A, 74A, 75A, 76A are fixed to the rigid portions 41A, 42A, 43A, 44A, 45A, 46A of the balloon 4, respectively. The hard members 7 protrude outward with respect to the balloon 4. A portion of the rigid portion 40A of the balloon 4 that is in contact with the side surface 701 of the hard member 7 is referred to as a "connection portion 401".

[0088] The circumferential length E2 of the side surface 701 of the rigid member 7 is shorter than the circumferential length E2 of the rigid portion 40A to which the rigid member 7 is connected. The two ends of the circumferential length E2 of each rigid portion 40A protrude to both sides of the rigid member 7 fixed to the rigid portion 40A in the circumferential direction E2. The ends 411 and 412 of the rigid portion 40A correspond to the ends 311 and 312 of the rigid portion 30A in the first embodiment, respectively. The ends 411 and 412 are collectively referred to as "end 410". The vertex where the two sides 702 of the rigid member 7 intersect (excluding the side surface 701) is called "vertex 700". The direction extending orthogonally to the side surface 701 and passing through vertex 700 is called the protrusion direction Y2. The protrusion direction Y2 points outward in the radial direction.

[0089] <Balloon 4's contraction / inflation>

[0090] like Figure 9 As shown, the contracted balloon 4 has blades 41C, 42C, 43C, 44C, 45C, and 46C (collectively referred to as "blades 40C"). Blades 40C are formed by folding together rigid portions 41A and 46B (blades 41C), rigid portions 42A and 41B (blades 42C), rigid portions 43A and 42B (blades 43C), rigid portions 44A and 43B (blades 44C), rigid portions 45A and 44B (blades 45C), and rigid portions 46A and 45B (blades 46C). In the cross-section of the balloon body 10B, blades 40C are positioned corresponding to the sides of a regular hexagon.

[0091] In the contracted state of the balloon 4, the end 412 of the rigid part 41A is close to the end 411 of the rigid part 42A. The end 412 of the rigid part 42A is close to the end 411 of the rigid part 43A. The positional relationship of the rigid parts 43A, 44A, 45A, and 46A is also the same. The outer portion of the rigid member 7, opposite to the side close to the reference axis C2, is covered by the blade 40C.

[0092] In the balloon 4 in its contracted state, unlike the balloon 3 of the first embodiment, the rigid portion 40A does not contact the inner tube 22 of the catheter shaft 2, but is separated from it. A rigid member 7 is sandwiched between the rigid portion 40A and the inner tube 22. A protruding direction Y2 extending from the side 701 of the rigid member 7 through the vertex 700 extends radially and toward the reference axis C2 on the inside.

[0093] The shortest distance between the rigid member 7 and the reference axis C2 is denoted as Dl. The distance Dl corresponds to the radial distance between the apex 700 of the rigid member 7 and the reference axis C2. The shortest distance between the linking portion 401 of the rigid portion 40A and the reference axis C2 is denoted as D2. The distance Dl is smaller than the distance D2.

[0094] As shown in Figure 10 , in the cross section of the balloon body 10B in which the balloon 4 is in the contracted state, an imaginary closed region S2 is defined. The imaginary closed region S2 is a region surrounded by the cross sections of the respective rigid portions 40A (the rigid portions 41A to 46A) in the case where the end portion 411 of the rigid portion 40A is linked with the end portion 412 of the other rigid portion 40A adjacent on one side in the circumferential direction E2 when the balloon 4 is in the expanded state (see Figure 10 ).

[0095] In the case of the balloon body 10B, for example, the six rigid portions 40A (the rigid portions 41A to 46A) are included, and thus the shape of the imaginary closed region S2 becomes a regular hexagon having the line segments represented by the cross sections of the respective rigid portions 41A to 46A as the respective sides. In addition, the angle between the rigid portion 40A and the other rigid portion 40A in the six corners (the linking portions T2 at which the end portion 411 of the rigid portion 40A is linked with the end portion 412 of the other rigid portion 40A) of the imaginary closed region S2 each becomes 120°.

[0096] In addition, the imaginary closed region S2 is defined in such a manner that the center K2 of the imaginary closed region S2 coincides with the position of the reference axis C2. Note that the center K2 of the imaginary closed region S2 corresponds to the center of gravity of the imaginary closed region S2. Also, the imaginary closed region S2 is defined in such a manner that all the sides of the imaginary closed region S2 are parallel to any one of the rigid portions 40A.

[0097] In the case where the imaginary closed region S2 is defined as described above, in the cross section of the balloon body 10B, a part of each of the rigid members 71A to 76A is disposed inside the imaginary closed region S2. In the cross section, an inscribed circle U21 is defined which is tangent to the leaf 40C of the balloon 4 in the contracted state and which has the reference axis C2 as the center. The radius of the inscribed circle U21 is denoted as R21.

[0098] Figure 9 A contracted state different from the actual contracted state of the balloon 4 (see Figure 10 ) is exemplified. In Figure 9In the state shown in FIG. 17, the line segments indicated by the cross sections of the rigid portions 41A to 46A are arranged at positions of the respective sides of the imaginary closed region S2. In this case, in the cross section of the balloon body 10B, the rigid members 71A to 76A are respectively arranged outside the imaginary closed region S2. In the cross section, an inscribed circle U22 is defined which is tangent to the blades respectively folded by the flexible portions 41B to 46B of the balloon 4 and which has the reference axis C2 as a center. The radius of the inscribed circle U22 is denoted by R22. The radius R22 is larger than the radius R21 in the state shown in FIG. 16. That is, by arranging the rigid portions 40A of the balloon 4 in the contracted state as shown in FIG. 17, the diameter of the balloon 4 is made smaller. Figure 9 In the state shown in FIG. 17, the line segments indicated by the cross sections of the rigid portions 41A to 46A are arranged at positions of the respective sides of the imaginary closed region S2. In this case, in the cross section of the balloon body 10B, the rigid members 71A to 76A are respectively arranged outside the imaginary closed region S2. In the cross section, an inscribed circle U22 is defined which is tangent to the blades respectively folded by the flexible portions 41B to 46B of the balloon 4 and which has the reference axis C2 as a center. The radius of the inscribed circle U22 is denoted by R22. The radius R22 is larger than the radius R21 in the state shown in FIG. 16. That is, by arranging the rigid portions 40A of the balloon 4 in the contracted state as shown in FIG. 17, the diameter of the balloon 4 is made smaller. Figure 11

[0099] Figure 11 The case where the balloon 4 of the balloon body 10B is deformed between the contracted state and the expanded state is shown. The balloon 4 in the contracted state shown in (A) of FIG. 18 is supplied with the compressed fluid from the catheter head not shown. In this case, as shown in (B) of FIG. 18, the flexible portions 41B to 46B of the balloon 4 are elongated, and the blades 41C to 46C (refer to (A) of FIG. 18) are eliminated. In addition, the rigid members 71A to 76A are respectively moved along the radial direction toward the outside while rotating to direct the protruding directions Y2 toward the outside. At this time, the rigid members 71A to 76A are respectively apart from the reference axis C2. Figure 11 Figure 11 Figure 11

[0100] In the case where the balloon 4 is further supplied with the compressed fluid, the rigid members 71A to 76A are respectively further moved in the direction apart from the reference axis C2. As a result, as shown in (C) of FIG. 19, the balloon 4 becomes the expanded state. At this time, the protruding directions Y2 of the rigid members 71A to 76A are directed toward the outside. Figure 11

[0101] On the other hand, the compressed fluid is removed from the balloon 4 in the expanded state shown in (C) of FIG. 20. In this case, as shown in (B) of FIG. 20, the flexible portions 41B to 46B of the balloon 4 are folded. In addition, the rigid members 71A to 76A are respectively moved along the radial direction toward the inside with respect to the positions in the expanded state (refer to (C) of FIG. 19). At this time, the rigid members 71A to 76A are respectively moved in the direction approaching the reference axis C2 while rotating to direct the protruding directions Y2 (refer to (A) of FIG. 20) toward the inside. Figure 11 Figure 11 Figure 7 Figure 11

[0102] ​​​​​​​​​As the compressed fluid is further removed from the balloon 4, the rigid members 71A to 76A rotate inwards in the protruding direction Y2, and move further towards the reference axis C2. Meanwhile, the flexible portions 41B to 46B of the balloon 4 fold over the rigid members 71A to 76A from the outside. Blades 41C to 46C are formed from the rigid portions 41A to 46A and the flexible portions 41B to 46B. Thus, as... Figure 11 As shown in (A), the balloon 4 is in a contracted state. At this time, the protruding direction Y2 of each of the rigid members 71A to 76A is directed toward the inward reference axis C2.

[0103] It should be noted that the balloon 4 has the following tendency: when changing from an inflated state to a contracted state, the rigid part 40A becomes... Figure 9 The configuration shown in (A).

[0104] <Function and Effects of the Second Embodiment>

[0105] In balloon catheter 1B, it is possible to set balloon 4 to a contracted state (see reference). Figure 10 The radius R21 of the balloon body 10B below is different from the state in which the rigid part 40A is arranged along the imaginary closed region S2 (refer to the state in which the rigid part 40A is arranged). Figure 12 The radius R22 of the balloon body 10B under the balloon 4 is small. Therefore, even when the balloon 4 is provided with a rigid member 7, the diameter of the balloon catheter 1B in the contracted state can be minimized.

[0106] The center K2 of the hypothetical closed region S2, corresponding to the center of gravity, is positioned aligned with the reference axis C2. In this case, the balloon catheter 1B enables the balloon body 10B to be uniformly miniaturized in the circumferential direction E2.

[0107] In the inflated balloon 4, the cross-section orthogonal to the reference axis C2 is approximately circular, and the reference axis C2 is positioned at equidistant points from all parts of the balloon 4. In this case, when the balloon catheter 1B sets the balloon 4, which has an approximately circular cross-section in the inflated state, to the contracted state, the diameter of the balloon body 10B can be minimized by uniformly contracting the balloon 4 in the circumferential direction E2.

[0108] When the balloon 4 is in the contracted state, the distance D1 between the rigid member 7 and the reference axis C2 is smaller than the distance D2 between the connecting part 401 of the rigid part 40A and the reference axis C2. In this case, when the balloon 4 is in the contracted state, the balloon body 10B can easily form a state in which each part of the rigid member 7 is arranged within the imaginary closed region S2.

[0109] <Variation Example>

[0110] The present application is not limited to the first embodiment and the second embodiment, and various modifications can be made. Hereinafter, the modifications will be specifically described with the first embodiment as an example, unless otherwise specified. However, the contents of the following modifications can also be appropriately applied to the second embodiment.

[0111] The inner tube 22 of the balloon catheter 1A can also not have the protruding portion 225. In this case, no tube is provided inside the balloon 3, and the tip 3D of the balloon 3 can also be plugged. Instead of the inner tube 22, a shaft having flexibility can also be provided.

[0112] The rigid member 6 can also be formed integrally with the balloon 3. That is, a part of the balloon 3 can also function as the rigid member 6. Note that in this case, the rigidity of the balloon 3 and the rigid member 6 can also be made different depending on the difference in the degree of orientation (degree of crystallization) of the resin constituting the balloon 3. The shape of the rigid member 6 is not limited to a triangular prism, and can be any other shape. For example, the end portion of the rigid member 6 on the side opposite to the joint portion that is joined to the rigid portion 30A of the balloon 3 can also not be sharp, but can be curved. The rigid member 6 can also not extend in the entire region of the extending direction in the inflated region 3B of the balloon 3. For example, the rigid member 6 can also be divided into a plurality of pieces in the extending direction. The rigid portion 30A, the flexible portion 30B, and the rigid member 6 can also be provided on the tip-side tapered region 3A and the base-end-side tapered region 3C of the balloon 3.

[0113] The rigid portion 30A and the flexible portion 30B can also be formed of the same material. Note that in this case, the rigidity of the rigid portion 30A and the flexible portion 30B can also be made different depending on the difference in the degree of orientation (degree of crystallization) of the resin constituting the balloon 3.

[0114] The boundary between the rigid portion 30A and the flexible portion 30B can also be defined based on a threshold value of rigidity. The rigid member 6 can also protrude further inward with respect to the rigid portion 30A.

[0115] The lengths of the circumferences E1 of the respective rigid portions 31A to 34A can each be different. In this case, the shape of the imaginary closed region S1 is not limited to a square, but becomes a polygon having the cross sections of the rigid portions 31A to 34A having different lengths as the respective sides. In addition, the shape of the rigid portion 30A is not limited to a planar shape, but can be curved. In this case, the shape of the imaginary closed region S1 is not limited to a square, but becomes a closed region surrounded by the cross sections of the curved rigid portions 31A to 34A.

[0116] The length of the circumference E1 of the rigid portion 30A can also be substantially the same as the length of the circumference E1 of the side surface 601 of the hard member 6. In this case, the both end portions on the circumference E1 of the rigid portion 30A can also not protrude from both sides of the circumference E1 of the hard member 6. Also, in this case, the hard member 6, the rigid portion 30A, and the connecting portion 301 can also be formed of the same material. By being configured as this structure, the balloon 3 can be easily manufactured.

[0117] The number of each of the rigid portion 30A, the flexible portion 30B, and the hard member 6 is not limited to four, and can also be any number of two or more.

[0118] The center K1 of the imaginary closed region S1 is not limited to the barycenter of the imaginary closed region S1. With reference to Figure 12 , a case in which the number of each of the rigid portion 30A, the flexible portion 30B, and the hard member 6 is three is exemplified and specifically described. A case in which the three rigid portions 30A are respectively denoted as rigid portions 35A, 36A, 37A and the imaginary closed region S3 is defined in this case is exemplified.

[0119] As shown in (A) of Figure 12 , the center K3 of the imaginary closed region S3 is not limited to the intersection point of the three medians L1 of the triangle representing the imaginary closed region S3, that is, the barycenter. For example, as shown in (B) of Figure 12 , the center K4 of the imaginary closed region S3 can also coincide with the intersection point of the perpendicular bisectors L2 of each side of the triangle representing the imaginary closed region S3, that is, the circumcenter. For example, as shown in (C) of Figure 12 , the center K5 of the imaginary closed region S3 can also coincide with the intersection point of the bisectors L3 of each vertex angle of the triangle representing the imaginary closed region S3, that is, the incenter. For example, as shown in (D) of Figure 13 , the center K6 of the imaginary closed region S3 can also coincide with the intersection point of the perpendiculars L4 from each vertex angle to the opposite side of the triangle representing the imaginary closed region S3, that is, the orthocenter. In these cases, the balloon catheter 1A can also uniformly downsize the diameter of the balloon body 10A in the circumference E1.

[0120] The shape of the cross section of the balloon 3 in the inflated state orthogonal to the reference axis C1 becomes a substantially circular shape with different curvatures at the rigid portion 30A and the flexible portion 30B. The radial distance from the reference axis C1 to the rigid portion 30A is slightly smaller than the radial distance from the reference axis C1 to the flexible portion 30B. Note that the shape of the cross section of the balloon 3 in the inflated state orthogonal to the reference axis C1 is not limited to a substantially circular shape, and can also be an elliptical shape, a polygonal shape, or the like.

[0121] When the balloon 3 is in the contracted state, the end portions 311 of the rigid portions 30A can also approach positions of the other rigid portion 30A other than the end portions 311, 312 and other than the joint portion 301 of the other rigid portion 30A.

[0122] The vane 31C can also cover the rigid member 64A from the outside. The vane 32C can also cover the rigid member 61A from the outside. The vane 33C can also cover the rigid member 62A from the outside. The vane 34C can also cover the rigid member 63A from the outside. The vane 30C can also not cover the rigid member 6 from the outside.

[0123] When the balloon 3 is in the contracted state, the rigid member 6, the rigid portions 30A, and the flexible portions 30B can also be configured as shown in Figure 13 In this case, the protruding direction Y1 of the rigid member 6 extends toward a direction orthogonal to the reference axis C1. In Figure 14 In this case, the protruding direction Y1 of the rigid member 6 extends toward a direction orthogonal to the reference axis C1. In

[0124] In the cross section of the balloon body 10B of the second embodiment, the rigid members 71A to 76A can also each configure all portions inside the imaginary closed region S2. In this case, the end portion 412 of the rigid portion 41A can also abut against the end portion 411 of the rigid portion 42A with the flexible portion 41B interposed therebetween. The end portion 412 of the rigid portion 42A can also abut against the end portion 411 of the rigid portion 43A with the flexible portion 42B interposed therebetween. The end portion 412 of the rigid portion 43A can also abut against the end portion 411 of the rigid portion 43A with the flexible portion 43B interposed therebetween. The end portion 412 of the rigid portion 44A can also abut against the end portion 411 of the rigid portion 44A with the flexible portion 44B interposed therebetween. In this case, the balloon catheter IB can minimize the diameter of the balloon body 10B in the case where the balloon 4 is in the contracted state.

[0125] The shape of the rigid member 6 and the configuration of the rigid portions 30A, the flexible portions 30B, the vanes 30C, and the rigid member 6 in the case where the balloon 3 is in the contracted state are not limited to the above. For example, various shapes and configurations shown in ​ may be provided.

[0126] <Other>

[0127] The inner tube 22 is an example of the "elongated member" of the present application.

Claims

1. A catheter balloon body comprising: A balloon that can deform into a contracted state and an inflated state; and Multiple rigid components are located on the sides of the balloon and protrude outwards. The balloon body for the catheter is characterized in that... The balloon has: a plurality of rigid portions, each including at least a connecting portion for each of the plurality of rigid components; and a plurality of flexible portions disposed circumferentially among the plurality of rigid portions and being softer than the plurality of rigid portions. When the balloon switches from the contracted state to the inflated state, each of the plurality of rigid members deforms in a direction away from a predetermined reference axis; and when the balloon switches from the inflated state to the contracted state, each of the plurality of rigid members deforms in a direction approaching the reference axis. The plurality of rigid components are rigider than the plurality of flexible parts of the balloon. In a cross section orthogonal to the reference axis, at least a portion of each of the plurality of rigid members of the balloon in the contracted state that protrude outward relative to the balloon is disposed in an imaginary closed region, which is a region formed when the circumferential end of each of the plurality of rigid members is connected to the circumferential end of another rigid member adjacent in the circumferential direction, and the reference axis is disposed at the center of the imaginary closed region.

2. The balloon body for catheters according to claim 1, characterized in that, The reference axis is located at any one of the centroid, incenter, circumcenter, or orthocenter of the imaginary closed region.

3. The balloon body for catheters according to claim 1 or 2, characterized in that, The shape of the cross-section of the inflated balloon orthogonal to the reference axis is approximately circular. The reference axis is positioned at an equidistant distance from each part of the balloon in its inflated state.

4. The balloon body for catheters according to claim 1 or 2, characterized in that, When the balloon is in the contracted state, the circumferential end of each of the plurality of rigid parts approaches the portion of the other rigid part that is adjacent in the circumferential direction, excluding the end.

5. The balloon body for catheters according to claim 4, characterized in that, When the balloon is in the contracted state, the circumferential end of each of the plurality of rigid parts approaches the connecting portion included in the other rigid part that is adjacent in the circumferential direction.

6. The balloon body for catheters according to claim 1 or 2, characterized in that, When the balloon is in the contracted state, each of the plurality of flexible portions covers the plurality of rigid members from the side opposite to the side of the plurality of rigid members that is close to the reference axis.

7. The balloon body for catheters according to claim 1 or 2, characterized in that, In a cross section orthogonal to the reference axis, all of the plurality of rigid members are arranged in the imaginary closed region.

8. The balloon body for catheters according to claim 1 or 2, wherein, When the balloon is in the contracted state, the shortest distance between the plurality of rigid members and the reference axis is smaller than the shortest distance between the midpoint of the circumferential direction of the plurality of connecting portions and the reference axis.

9. The balloon body for catheters according to claim 1 or 2, characterized in that, The rigid part and the connecting part have the same circumferential length, and the rigid member, the rigid part, and the connecting part are made of the same material.

10. A balloon catheter, characterized in that, The balloon catheter has the following features: The catheter balloon body according to any one of claims 1 to 6; and A long strip member extending along the reference axis and inserted through the balloon. When the balloon is in the contracted state, each of the plurality of rigid parts is connected to the elongated member.

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