Catheter device

Abstract

To provide a catheter device which is advantageous in securing breaking resistance related to a structure around an end of an expansion member.SOLUTION: The catheter includes a catheter shaft 12, an expansion member 14 provided at a distal end side portion of the catheter shaft 12, and a crimp tube 30A for crimping an axial end 16A of the expansion member 14 to the catheter shaft 12, wherein a reinforcement part 30A is provided on the end 32A of the expansion member 14. The reinforcing portion side 32A may be provided so as to straddle, in the axial direction, a position side 16A that overlaps, in the radial direction, the edge portion side 16c of the crimping tube side P1 on the inner side of the expansion member 14 in the axial direction.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to catheter devices. [Background technology]

[0002] Patent Document 1 discloses a catheter device including a catheter shaft and an expansion member provided at the distal end portion of the catheter shaft. The axial end of the expansion member may be crimped to the catheter shaft by a crimp tube. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-124264 Summary of the Invention [Problem to be solved by the invention]

[0004] There are cases where it is required to ensure breakage resistance for the structure around the end of the expansion member that is crimped by the crimp tube.

[0005] Therefore, one object of the present disclosure is to provide a catheter device that is advantageous in ensuring breakage resistance for the structure around the end of the expansion member. [Means for solving the problem]

[0006] The catheter device of the present disclosure comprises a catheter shaft, an expansion member provided at the distal end portion of the catheter shaft, and a crimping tube that crimps the axial end of the expansion member to the catheter shaft, and a reinforcing portion is provided at the end of the expansion member. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a side view showing a catheter device of a first embodiment. [Figure 2] FIG. 2 is a side cross-sectional view schematically showing the configuration around an expansion member of the catheter device of the first embodiment. [Figure 3] FIG. 2 is a side cross-sectional view schematically showing the periphery of the proximal end of the expansion member of the catheter device of the first embodiment. [Figure 4] FIG. 10 is a side cross-sectional view schematically showing a state during a crimping step. [Figure 5] FIG. 2 is a side cross-sectional view schematically showing the periphery of the distal end portion of the expansion member of the catheter device of the first embodiment. [Figure 6] FIG. 4 is a side cross-sectional view of a catheter device according to a second embodiment, seen from the same viewpoint as in FIG. 3. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment for implementing the catheter device of the present disclosure will be described. The same or equivalent elements will be given the same reference numerals, and duplicate explanations will be omitted. In each drawing, for the sake of convenience, components will be omitted, enlarged, or reduced in size as appropriate. The drawings should be viewed in accordance with the orientation of the reference numerals.

[0009] Referring to Figure 1, the catheter device 10 is used for treatment, such as medical treatment and examination of a living body. The treatment here is, for example, dilating a narrowed area of ​​the living body (for example, the papilla of the bile duct). The organs to be treated include, for example, (1) digestive organs such as the intestine and bile duct, and (2) circulatory organs such as the heart and blood vessels.

[0010] The catheter device 10 includes a catheter shaft 12, an expansion member 14 provided at the distal end of the catheter shaft 12, crimping tubes 16A and 16B that crimp the axial ends of the expansion member 14 to the catheter shaft 12, and a handle 18 provided at the proximal end of the catheter shaft 12 and held by the surgeon. In this specification, the direction along the center line of the catheter shaft 12 is simply referred to as the "axial direction," and the radial and circumferential directions based on that center line are simply referred to as the "radial direction" and the "circumferential direction." In addition, one axial side (the right side of the paper in Figure 1) is also referred to as the proximal end, and the other axial side (the left side of the paper in Figure 1) is also referred to as the distal end.

[0011] See Figure 2. Hereinafter, the side away from the axial center position C14 of the expansion member 14 in the axial direction will be referred to as the axial outer side of the expansion member 14, and the side approaching the axial center position C14 in the axial direction will be referred to as the axial inner side of the expansion member 14.

[0012] At least the distal end of the catheter shaft 12 is inserted into the body. The catheter shaft 12 is flexible and bendable. The catheter shaft 12 is composed of at least one shaft member 20A, 20B. The catheter shaft 12 of this embodiment includes a first shaft member 20A and a second shaft member 20B, arranged in this order from the proximal end to the distal end of the catheter shaft 12. The multiple shaft members 20A, 20B are joined in series in the axial direction by welding or other methods. The shaft members 20A, 20B are composed of various materials, including known materials for constructing catheter shafts 12. Examples of such materials include synthetic resins such as polyether block amide, polyamide, polyolefin, and polytetrafluoroethylene. The number of shaft members 20A, 20B constituting the catheter shaft 12 is not particularly limited and may be one, three, or more. The catheter shaft 12 may be formed with a device lumen (not shown) through which a medical device such as a guidewire can be passed and then withdrawn from the distal end of the catheter shaft 12. The device lumen may be formed, for example, inside the first shaft member 20A and the second shaft member 20B.

[0013] The catheter device 10 of this embodiment includes a balloon 22 provided at the distal end portion of the catheter shaft 12, separate from the expansion member 14. The balloon 22 is made of various resin materials used for balloons, such as nylon, nylon-based elastomer, polyurethane, and polyethylene terephthalate.

[0014] The balloon 22 defines a fluid chamber 22a therein, to which a fluid is supplied. This fluid is supplied to the fluid chamber 22a from an inlet port (not shown) provided in the handle 18 via a fluid lumen (not shown) in the catheter shaft 12. In this embodiment, the fluid lumen communicates with an opening (not shown) in the distal end 20Aa of the first shaft member 20A.

[0015] The balloon 22 includes an expansion section 22b that can be expanded by fluid supplied to the fluid chamber 22a. Figures 1 and 2 show the expansion section 22b of the balloon 22 in an expanded state. The expansion section 22b can be contracted by discharging the fluid in the fluid chamber 22a to the outside via the fluid lumen. The expansion section 22b in this embodiment includes a cylindrical section 22c that extends in the axial direction, and a pair of cone sections 22d that are provided on the proximal and distal ends of the cylindrical section 22c, respectively, and that decrease in diameter as they move away from the cylindrical section 22c in the axial direction. The specific shape of the expansion section 22b is not particularly limited, and may be, for example, spherical.

[0016] The balloon 22 includes a sleeve portion 22e provided at least on the proximal side relative to the expansion portion 22b. In this embodiment, the sleeve portion 22e is provided separately on the proximal side and the distal side relative to the expansion portion 22b. The sleeve portion 22e is tubular and surrounds the catheter shaft 12. The sleeve portion 22e is airtightly fixed to the catheter shaft 12 by welding, bonding, crimping, or the like. In this embodiment, the proximal sleeve portion 22e is fixed to the first shaft member 20A by welding, and the distal sleeve portion 22e is fixed to the second shaft member 20B by welding. The outer diameter of the sleeve portion 22e is maintained before and after the expansion portion 22b of the balloon 22 is expanded.

[0017] A restraining member 24 is wrapped around the expansion portion 22b of the balloon 22. The restraining member 24 is used to restrain the expansion of a portion of the balloon 22 in the axial direction when the balloon 22 expands. The restraining member 24 is made of an elastic material that can elastically deform in response to the expansion of the balloon 22. When the balloon 22 expands, an adjacent portion of the balloon 22 adjacent to the portion restrained by the restraining member 24 is expanded first, thereby forming a constricted portion in the balloon 22 at the constricted portion. By locating a stenotic portion of biological tissue (e.g., the papilla) inside the recess formed by the constricted portion on the outer periphery of the balloon 22, it becomes easier to position the catheter shaft 12 axially relative to the stenotic portion. After a constricted portion is formed in the balloon 22, the balloon 22 can be further expanded to reduce the difference in outer diameter between the constricted portion and the adjacent portion of the balloon 22. This difference in outer diameter can also be reduced to almost zero. Figures 1 and 2 schematically show a state in which this difference in outer diameter is zero.

[0018] The expansion member 14 in this embodiment is composed of a covering member 26 that covers the balloon 22. Alternatively, the expansion member 14 may be composed of the balloon 22 as described in the second embodiment. In either case, the expansion member 14 is exposed to the external space surrounding the catheter shaft 12. The covering member 26 covers the entire expansion portion 22b of the balloon 22 and at least partially covers the sleeve portion 22e. The covering member 26 in this embodiment also covers the restraining member 24, preventing the restraining member 24 from falling off.

[0019] The expansion member 14 is fixed to the catheter shaft 12 at least at its base end in the axial direction. In this embodiment, the expansion member 14 is fixed to the catheter shaft 12 at both axial ends. To satisfy this condition, in this embodiment, both axial ends of the expansion member 14 are fixed by individual crimped tubes 16A, 16B. Alternatively, one end may be fixed by a crimped tube and the other end may be fixed by adhesive, welding, or the like.

[0020] The expansion member 14 is expandable by fluid supplied to the fluid chamber 22a and is contractable by discharging the fluid to the outside. The covering member 26 that constitutes the expansion member 14 is made of a resin-based material that can elastically deform in response to the expansion of the balloon 22. This resin-based material is, for example, polyurethane. This allows the covering member 26 that constitutes the expansion member 14 to deform to follow the shape of the balloon 22 as the balloon 22 expands and contracts.

[0021] The crimped tubes 16A, 16B in this embodiment include a first crimped tube 16A that crimps the proximal end 30A of the expansion member 14 to the catheter shaft 12, and a second crimped tube 16B that crimps the distal end 30B of the expansion member 14 to the catheter shaft 12. Crimping here refers to fixing by compression, regardless of whether adhesive or welding is used. In this embodiment, it refers to fixing the ends 30A, 30B of the expansion member 14 to the catheter shaft 12 by compressing them with the crimped tubes 16A, 16B. When crimping the expansion member 14 in this manner, other members such as a balloon 22 may be present between the expansion member 14 and the catheter shaft 12.

[0022] In this embodiment, reinforcing portions 32A, 32B are provided at the ends 30A, 30B of the expansion member 14. The reinforcing portions 32A, 32B in this embodiment include a first reinforcing portion 32A provided at the base end 30A of the expansion member 14 and a second reinforcing portion 32B provided at the distal end 30B of the expansion member 14.

[0023] Please refer to Figure 3. Below, we will explain the surrounding structure of the proximal end portion 30A of the expansion member 14. Here, the surrounding structure of the proximal end portion 30A refers to a structure including the first crimped tube 16A, the first reinforcing portion 32A, etc.

[0024] The crimped tube 16A is joined to the catheter shaft 12 at a first portion 16a located axially outward of the expansion member 14. To achieve this, the crimped tube 16A in this embodiment is joined to the catheter shaft 12 by welding, but may also be joined by adhesive or the like. The crimped tube 16A also crimps the end portion 30A of the expansion member 14 to the catheter shaft 12 at a second portion 16b located axially inward of the expansion member 14.

[0025] Please refer to Figure 4. Figure 4 shows an example of a crimping step in which the end 30A of the expansion member 14 is crimped with the crimp tube 16A. The crimping step can be performed, for example, by (1) using a heat-shrinkable tube 36 separate from the crimp tube 16A and heating the heat-shrinkable tube 36 together with the crimp tube 16A, or (2) forming the crimp tube 16A from a heat-shrinkable tube and heating the crimp tube 16A. In either case, the crimping step is performed by heating at least the crimp tube 16A. Here, an example of performing the crimping step in the manner of (1) is shown.

[0026] The heat-shrinkable tube 36 is a tube that shrinks to reduce its diameter when heated. The heat-shrinkable tube 36 is made of various materials, such as resin-based materials, that have such properties. The heat-shrinkable tube 36 used in this example covers the entire crimped tube 16A. The crimping process in this example is performed by heating the heat-shrinkable tube 36 together with the crimped tube 16A using a heating machine such as a hair dryer, and shrinking the heat-shrinkable tube 36.

[0027] In the case of the above-described embodiment (1), the crimped tube 16A also shrinks in diameter due to plastic flow following the shrinkage of the heat-shrinkable tube 36. After this, the heat-shrinkable tube 36 is peeled off from the crimped tube 16A. At this time, the crimped tube 16A is maintained in a contracted state, and the end 30A of the expansion member 14 is maintained in a state of being crimped to the catheter shaft 12 by the second portion 16b of the crimped tube 16A.

[0028] In the case of the aforementioned embodiment (2), the crimped tube 16A that constitutes the heat-shrinkable tube itself is shrunk by heating, and by maintaining it in that state, the end 30A of the expansion member 14 is maintained in a state in which it is crimped to the catheter shaft 12 by the crimped tube 16A.

[0029] In either of the above-described embodiments (1) and (2), at least the crimped tube 16A is heated, whereby the crimped tube 16A shrinks and the first portion 16a of the crimped tube 16A is welded to the catheter shaft 12.

[0030] Referring to Figure 3, the end 30A of the expansion member 14 is provided with a crimped portion 30a that is crimped by the crimped tube 16A and a non-crimped portion 30b that is not crimped by the crimped tube 16A. The crimped portion 30a is provided at a location that radially overlaps with the crimped tube 16A. The non-crimped portion 30b is provided axially inward of the expansion member 14 from the crimped portion 30a at a location that does not radially overlap with the crimped tube 16A.

[0031] The reinforcing portion 32A reinforces the strength (particularly the tensile strength) of the end portion 30A of the expansion member 14. The reinforcing portion 32A reinforces the strength of the end portion 30A by increasing the thickness of the end portion structure, including the end portion 30A of the expansion member 14, by the amount of the reinforcing portion 32A. To satisfy this condition, the reinforcing portion 32A in this embodiment is formed by a reinforcing member 34 that is provided separately from the expansion member 14. Alternatively, to satisfy this condition, the reinforcing portion 32A may be formed integrally with the other portions of the expansion member 14 using the same material. In this case, a thick portion that is thicker than an axially adjacent thin portion is provided at a certain location of the reinforcing portion 32A, and the reinforcing portion 32A is formed by a portion that is thicker than the thin portion.

[0032] In this embodiment, the reinforcing portion 32A is provided so as to straddle a position P1 in the axial direction, which radially overlaps with the edge portion 16c of the crimped tube 16A located axially inside the expansion member 14. The wider the axial range of the reinforcing portion 32A, the more stably the reinforcing portion 32A can be positioned so as to straddle position P1 in the axial direction, even if the crimped tube 16A is misaligned axially with respect to the expansion member 14. The reinforcing portion 32A may be designed to be provided so as to exist at least within an axial range of a predetermined tolerance, centered on the edge portion 16c of the crimped tube 16A. In this embodiment, the reinforcing portion 32A is provided at least in the axial range from position P1 to the edge portion 14a of the expansion member 14 located axially outside the expansion member 14. The reinforcing portion 32A is provided at least in a position from the edge portion 16c of the crimped tube 16A to a position radially overlapping the entire crimped portion 30a of the expansion member 14 located axially outside the expansion member 14.

[0033] The reinforcing member 34 constituting the reinforcing portion 32A described above is disposed at a position radially overlapping the end portion 30A of the expansion member 14. The reinforcing member 34 in this embodiment is disposed radially inward of the expansion member 14. The portion extending from an edge portion 34a of the reinforcing member 34 located axially inward of the expansion member 14 to the axially outward of the expansion member 14 is covered by the expansion member 14. The reinforcing member 34 in this embodiment is cylindrical, but the shape is not limited to this and may be a half-cylindrical shape, for example.

[0034] The reinforcing member 34 is welded to the expansion member 14. To satisfy the condition of "welding," it is sufficient that the expansion member 14 and the reinforcing member 34 are welded to each other over at least a portion of the circumferential range; it is not necessary that the expansion member 14 and the reinforcing member 34 are welded to each other over the entire circumferential range. In order to weld the reinforcing member 34 to the expansion member 14 in this way, a welding process in which the end 30A of the expansion member 14 is welded to the reinforcing member 34 by heating may be performed prior to the aforementioned crimping process. The reinforcing member 34 is made of a material, such as a resin-based material, that can be welded to the expansion member 14. To achieve this, the reinforcing member 34 may be made of the same material as the expansion member 14, or a different material from the expansion member 14.

[0035] The reinforcing member 34 has a welded region 34b that is welded to the expansion member 14 and a non-welded region 34c that is located axially inward of the expansion member 14 relative to the welded region 34b and is not welded to the expansion member 14. For ease of explanation, in FIG. 3 , the welded portion between the reinforcing member 34 and the expansion member 14 is shown surrounded by a two-dot chain line. The reinforcing portion 32A that reinforces the end portion 30A of the expansion member 14 is composed of the welded region 34b of the reinforcing member 34. The thickness of the end portion structure of the expansion member 14 in the welded region 34b is increased by the amount of the reinforcing member 34, thereby reinforcing the strength of the end portion 30A of the expansion member 14.

[0036] The non-welded region 34c of the reinforcing member 34 is provided in an axial range that continues from the edge 34a of the reinforcing member 34, which is on the axially inner side of the expansion member 14, to the axially outer side of the expansion member 14. The boundary between the welded region 34b and the non-welded region 34c is located axially more inward of the expansion member 14 than the edge 16c of the crimped tube 16A. The non-welded region 34c is not provided in a position that radially overlaps with the crimped portion 30a of the expansion member 14, but is provided in a position that radially overlaps with the non-crimped portion 30b.

[0037] The effects of the catheter device 10 described above will now be described.

[0038] The catheter device 10 includes a reinforcing portion 32A provided at the end 30A of the expansion member 14. Therefore, the reinforcing portion 32A can reinforce the tensile strength of the structure around the end 30A of the expansion member 14 (hereinafter referred to as the end structure of the expansion member 14). As a result, when a tensile force is applied to the expansion member 14 during expansion, the reinforcing portion 32A can suppress breakage of the end structure, which is advantageous in ensuring the breakage resistance of the end structure. Here, the end structure of the expansion member 14 refers to a structure consisting of only the expansion member 14 if there is no reinforcing member 34 separate from the expansion member 14, or refers to a structure combining the expansion member 14 and the reinforcing member 34 if there is a reinforcing member 34 separate from the expansion member 14.

[0039] Furthermore, according to this embodiment, the fracture resistance of the end structure of the expansion member 14 can be ensured without increasing the thickness of the expansion member 14 at any location other than the end 30A. This is advantageous in ensuring the fracture resistance of the end structure of the expansion member 14 while suppressing an increase in the outer diameter of the catheter device 10 that would result from an increase in the thickness of the expansion member 14 at any location other than the end 30A. In other words, it can be said that this is advantageous in ensuring the fracture resistance of the end structure of the expansion member 14 while reducing the thickness of the expansion member 14 at any location other than the end 30A.

[0040] A tensile force is applied to the expansion member 14 exposed to the external space not only when the expansion member 14 is expanded but also when the expansion member 14 slides against an external object. Even when such a tensile force is applied, this is advantageous in ensuring the breakage resistance of the end structure of the expansion member 14. An example of an external object here is an endoscope. When an endoscope is used, the catheter device 10 is used by passing it through the lumen of the endoscope that is placed first inside the body.

[0041] When the end 30A of the expansion member 14 is crimped by the crimped tube 16A, the crimped portion 30a of the expansion member 14 is deformed by the crimped tube 16A so that the diameter thereof is slightly smaller than that of the non-crimped portion 30b. As a result, a cross-sectionally changing portion (not shown) whose cross-sectional shape changes in a cut surface along the axial direction of the expansion member 14 is formed around position P1 where the crimped portion 30a radially overlaps with edge portion 16c of the crimped tube 16A. As a result, when a tensile force is applied to the expansion member 14, stress tends to concentrate locally in the cross-sectionally changing portion of the expansion member 14, making the end 30A of the expansion member 14 more likely to break.

[0042] Furthermore, in the crimping process in which the end 30A of the expansion member 14 is crimped with the crimp tube 16A, at least the crimp tube 16A is heated to shrink the crimp tube 16A. When the crimp tube 16A is heated in this manner, the end 30A of the expansion member 14 around the crimp tube 16A is also partially heated, which can lead to a decrease in tensile strength due to thermal degradation, depending on the material of the expansion member 14. Due to this thermal degradation, it is difficult to ensure the tensile strength of the expansion member 14 around position P1 where the expansion member 14 radially overlaps with the edge 16c of the crimp tube 16A, which makes the expansion member 14 more susceptible to breakage.

[0043] To address this issue, the reinforcing portion 32A in this embodiment is provided so as to straddle a position P1 that radially overlaps the edge portion 16c of the crimped tube 16A in the axial direction. This allows the reinforcing portion 32A to reinforce the tensile strength of the end portion 30A of the expansion member 14 around position P1. Consequently, even if a cross-sectionally varying portion that could cause breakage is provided in the expansion member 14 around position P1, breakage can be suppressed. Furthermore, even if the tensile strength of the end portion 30A of the expansion member 14 around position P1 decreases due to thermal degradation during the crimping process of the crimped tube 16A, breakage can be suppressed. This is advantageous in ensuring the breakage resistance of the end portion structure of the expansion member 14.

[0044] When the crimped tube 16A is heated during the crimping process, the expansion member 14 located radially overlapping the crimped tube 16A is heated along with the crimped tube 16A, and the tensile strength of the expansion member 14 may decrease due to thermal degradation. The reinforcing portion 32A of this embodiment is provided at least in the axial range from position P1, where the expansion member 14 radially overlaps with the edge portion 16c of the crimped tube 16A, to the edge portion 14a of the expansion member 14. In other words, the reinforcing portion 32A is provided over the entire expansion member 14 located radially overlapping the crimped tube 16A, where the tensile strength may decrease due to thermal degradation during the crimping process. Therefore, even if the tensile strength of the expansion member 14 in this axial range decreases due to thermal degradation during the crimping process, the reinforcing portion 32A can prevent the expansion member 14 from breaking.

[0045] Consider the case where the reinforcing member 34 is disposed radially outward from the expansion member 14. In this case, depending on the state of welding of the reinforcing member 34 to the expansion member 14, there is a risk that the edges on both the base end and the tip end of the reinforcing member 34 may curl up and interfere with an external object. In this regard, the reinforcing member 34 of this embodiment is disposed radially inward from the expansion member 14. This makes it possible to prevent the edges of the reinforcing member 34 from curling up and interfering with an external object, thereby avoiding an increase in sliding resistance against the external object.

[0046] The reinforcing member 34 has a non-welded region 34c that is located axially inward of the welded region 34b and is not welded to the expansion member 14. As a result, in the welding process in which the reinforcing member 34 is welded to the expansion member 14 by heating, the heating range of the expansion member 14 can be narrowed in the axial direction by using the non-welded region 34c of the reinforcing member 34 as the welded region 34b. As a result, the axial range in which the expansion member 14 is affected by thermal degradation due to heating in the welding process can be narrowed, which is advantageous in ensuring the fracture resistance of the end structure of the expansion member 14.

[0047] See Figure 5. The peripheral structure of the proximal end 30A of the expansion member 14 and the effects of that peripheral structure described so far also apply to the peripheral structure of the distal end 30B. Here, the peripheral structure of the distal end 30B refers to a structure including the second crimped tube 16B, the second reinforcing portion 32B, etc. The peripheral structure of the distal end 30B in this embodiment differs from the peripheral structure of the proximal end 30A mainly in the following two points (1) and (2), but is otherwise common. (1) The peripheral structure of the distal end 30B is axially inverted relative to the peripheral structure of the proximal end 30A. (2) The distal end 30B and other components are fixed to the second shaft member 20B rather than the first shaft member 20A of the catheter shaft 12. For this reason, the peripheral structure of the distal end 30B is merely illustrated here, and a detailed description thereof will be omitted. Furthermore, the features of the peripheral structure of the base end portion 30A described so far may be applied to only one of the peripheral structure of the base end portion 30A and the peripheral structure of the distal end portion 30B. For example, they may be applied only to the peripheral structure of the distal end portion 30B, and not to the peripheral structure of the base end portion 30A. Alternatively, they may be applied only to the peripheral structure of the base end portion 30A.

[0048] As described above, the reinforcing portions 32A, 32B in this embodiment include a first reinforcing portion 32A provided at the base end 30A of the expansion member 14 and a second reinforcing portion 32B provided at the distal end 30B. Therefore, the first reinforcing portion 32A ensures the breakage resistance of the end structure around the base end 30A of the expansion member 14, while the second reinforcing portion 32B ensures the breakage resistance of the end structure around the distal end 30B.

[0049] Another feature of the catheter device 10 will now be described. Refer to FIG. 2. The reinforcing portions 32A and 32B are provided axially outward of the balloon 22 from the axial center portion 22f of the expansion portion 22b of the balloon 22. Here, the axial outside of the balloon 22 refers to the side that is farther away from the axial center position of the balloon 22 in the axial direction. The reinforcing portions 32A and 32B are provided at positions that do not overlap radially with the axial center portion 22f of the balloon 22. Here, the axial center portion 22f refers to the quarter position P, which is a position that divides the expansion portion 22b into four equal parts in the axial direction. 1 / 4 , 2 / 4 position P2 / 4 , 3 / 4 position P 3 / 4 In this case, 1 / 4 position P 1 / 4 From 3 / 4 position P 3 / 4 This refers to the area up to

[0050] This makes it easier to inflate the balloon 22 compared to when the reinforcing portions 32A, 32B are provided in the axial range including the axial central portion 22f of the balloon 22. Also, compared to when the reinforcing portions 32A, 32B are provided in the axial central portion 22f of the balloon 22, an increase in the outer diameter of the catheter device 10 in the axial range where the axial central portion 22f of the balloon 22 is located can be suppressed.

[0051] The reinforcing portions 32A, 32B are provided axially outward of the entire expansion portion 22b of the balloon 22. The reinforcing portions 32A, 32B are provided at positions that do not radially overlap with the entire expansion portion 22b of the balloon 22. This makes it easier to expand the balloon 22 compared to when the reinforcing portions 32A, 32B are provided in an axial range that includes the expansion portion 22b of the balloon 22. Furthermore, compared to when the reinforcing portions 32A, 32B are provided in an axial range that includes the expansion portion 22b of the balloon 22, an increase in the outer diameter of the catheter device 10 in the axial range where the expansion portion 22b of the balloon 22 is located can be suppressed.

[0052] (Second embodiment) See Fig. 6. In the following embodiments, among the components described in the first embodiment, the same content as in the first embodiment may be applied to the components that are not described below.

[0053] The catheter device 10 of this embodiment does not include the restraining member 24 and covering member 26 of the first embodiment. The expansion member 14 of this embodiment is composed of a balloon 22. The end of the balloon 22, which becomes the expansion member 14, is crimped to the catheter shaft 12 by crimping tubes 16A and 16B. To achieve this, the balloon 22 may or may not be welded to the catheter shaft 12. In this embodiment, a sleeve portion 22e at the end of the balloon 22 is airtightly fixed to the catheter shaft 12 by crimping.

[0054] The reinforcing portion 32A in this embodiment reinforces the end portion 30A of the expansion member 14 constituting the balloon 22. In this embodiment as well, the reinforcing portion 32A is composed of a reinforcing member 34. The reinforcing member 34 is welded to the sleeve portion 22e of the balloon 22.

[0055] The above embodiment can also achieve the same effects as in Embodiment 1. Here, only the peripheral structure of the proximal end 30A of the expansion member 14 has been described, but a similar configuration may also be applied to the peripheral structure of the distal end 30B thereof.

[0056] Next, variations of the components described above will be described.

[0057] The reinforcing portions 32A, 32B may be provided only at positions that do not radially overlap with the edge portions 16c of the crimped tubes 16A, 16B. The reinforcing portions 32A, 32B may be provided, for example, only at the crimped portions 30a and the non-crimped portions 30b of the end portions 30A, 30B of the expansion member 14. The reinforcing portions 32A, 32B may not necessarily be provided in the axial range up to the edge portion 14a of the expansion member 14, so long as they are provided so as to straddle the position P1 at which they radially overlap with the edge portions 16c of the crimped tubes 16A, 16B. The reinforcing portions 32A, 32B may be provided at positions that overlap with part of the expansion portion 22b of the balloon 22 when viewed in the radial direction. The catheter device 10 may include only one of the first reinforcing portion 32A and the second reinforcing portion 32B. The reinforcing portions 32A, 32B may be formed by folding back a portion of the end portion 30A, 30B of the expansion member 14 and welding the overlapping portion that overlaps the folded portion radially to the folded portion, thereby forming a welded portion at the folded portion.

[0058] The reinforcing member 34 may be disposed radially outward from the expansion member 14. The reinforcing member 34 may have only the welded region 34b without the non-welded region 34c.

[0059] The content of each component described in the above embodiments is an example. The abstract technical ideas should not be interpreted as being limited to the content of this specification. The content of each component described in the embodiments is subject to many design changes, such as modifications, additions, and deletions. Contents subject to such design changes are emphasized by adding the notation "this embodiment" or "embodiment." However, design changes are also permitted even in content not labeled as such. Any combination of the above components is also valid. Hatching on cross sections in the drawings does not limit the material of the hatched objects. [Explanation of symbols]

[0060] 10...catheter device, 12...catheter shaft, 14...expansion member, 14a...edge portion, 16A...first crimped tube, 16B...second crimped tube, 22...balloon, 22b...expansion portion, 22f...axial central portion, 26...covering member, 30A...base end portion, 30B...distal end portion, 32A...first reinforcing portion, 32B...second reinforcing portion, 34...reinforcing member, 34a...edge portion, 34b...welded region, 34c...non-welded region.

Claims

1. A catheter shaft; an expansion member provided at a distal end portion of the catheter shaft; a crimping tube that crimps an axial end of the expansion member onto the catheter shaft, A catheter device in which a reinforcing portion is provided at the end of the expansion member.

2. The catheter device according to claim 1 , wherein the reinforcing portion is provided so as to straddle in the axial direction a position that radially overlaps an edge portion of the crimped tube that is located axially inside the expansion member.

3. The catheter device according to claim 2 , wherein the reinforcing portion is provided at least in an axial range from a position radially overlapping with the edge portion to an edge portion of the expansion member that is axially outward of the expansion member.

4. A balloon is provided as part of the expansion member or separately from the expansion member, the balloon comprises an expandable extension; The catheter device according to claim 1 , wherein the reinforcing portion is provided axially outward of the balloon relative to the axial center of the expansion portion.

5. A balloon is provided as part of the expansion member or separately from the expansion member, the balloon comprises an expandable extension; The catheter device according to claim 1 , wherein the reinforcing portion is provided axially outward of the balloon relative to the entire expansion portion.

6. The catheter device according to claim 1 , wherein the reinforcing portion is formed by a reinforcing member provided separately from the expansion member.

7. The catheter device according to claim 6 , wherein the reinforcing member is disposed radially inward relative to the expansion member.

8. 8. The catheter device according to claim 7, wherein the reinforcing member comprises a welded region that is welded to the expansion member, and a non-welded region that is located axially inward of the welded region and is not welded to the expansion member.

9. the crimp tube includes a first crimp tube that crimps the proximal end of the expansion member onto the catheter shaft, and a second crimp tube that crimps the distal end of the expansion member onto the catheter shaft, The catheter device according to claim 1 , wherein the reinforcing portion includes a first reinforcing portion provided at the base end portion and a second reinforcing portion provided at the distal end portion.

10. a balloon provided at a distal end portion of the catheter shaft; a covering member that covers the balloon, The catheter device according to claim 1 , wherein the expansion member is the covering member.

11. a balloon provided at a distal end portion of the catheter shaft; The catheter device according to claim 1 , wherein the expansion member is the balloon.

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