WO2025150255A1 - Balloon catheter - Google Patents

Abstract

This balloon catheter (100) has a group of balloon members, which includes a plurality of balloon members that are arranged, and a proximal shaft member (3) disposed proximally to the balloon members. The group of balloon members includes an inner balloon member and an outer balloon member. The proximal shaft member (3) has a guide wire lumen (30), a first lumen (31), and second lumens (32). In a cross section perpendicular to the longitudinal direction of the proximal shaft member (3), the distance between the centroid (30c) of the guide wire lumen (30) and the centroid (32c) of each second lumen (32) is larger than the distance between the centroid (30c) of the guide wire lumen (30) and the centroid (31c) of the first lumen (31).

Description

Balloon catheter

The present invention relates to a balloon catheter.

When narrowed areas hardened by calcification form in the walls of blood vessels, it can lead to diseases such as angina and myocardial infarction. One treatment for this is angioplasty, which uses a balloon catheter to expand the narrowed area. Angioplasty is a minimally invasive therapy that does not require open chest surgery like bypass surgery, and is a widely used treatment.

Aortic valve stenosis is a condition in which the aortic valve becomes hardened due to calcification, making it difficult to open, and thus impeding blood flow. Treatments for aortic valve stenosis include aortic valve replacement, which involves opening the chest, and transcatheter aortic valve replacement, in which a biological valve (artificial valve) is placed via catheter to replace the hardened aortic valve.

Patent Document 1 discloses a balloon catheter used for dilating hardened stenotic areas and placing biological valves, in which multiple outer balloon members are arranged to surround the outer surface of an inner balloon member.

US Patent Application Publication No. 2012/0209375

However, with the balloon catheter described in Patent Document 1, as the number of balloons increases, it becomes difficult to ensure the thickness of the portion of the shaft between the lumens in which the inflation lumen and the guidewire lumen are formed. This can result in fluid leaking from the inflation lumen into the guidewire lumen.

The present invention was made in consideration of the above circumstances, and its purpose is to provide a balloon catheter that can easily prevent fluid from leaking into the guidewire lumen.

One embodiment of the balloon catheter of the present invention that can solve the above problems is as follows.
[1] A balloon portion group including a plurality of balloon portions arranged in parallel;
a proximal shaft portion located proximal to the balloon portion,
The balloon portion group includes an inner balloon portion having a guidewire tube into which a guidewire is inserted, and an outer balloon portion located radially outward of the inner balloon portion,
the proximal shaft portion has a guidewire lumen into which the guidewire is inserted, a first lumen through which a fluid supplied to the inner balloon portion can pass, and a second lumen through which a fluid supplied to the outer balloon portion can pass,
A balloon catheter, in which, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion, the distance between the centroid of the guidewire lumen and the centroid of the second lumen is longer than the distance between the centroid of the guidewire lumen and the centroid of the first lumen.

By making the distance between the centroid of the guidewire lumen and the centroid of the second lumen longer than the distance between the centroid of the guidewire lumen and the centroid of the first lumen, it is possible to prevent the portion between the second lumen and the guidewire lumen from becoming too thin due to the second lumen coming too close to the guidewire lumen. This makes it easier to prevent fluid from leaking from the second lumen into the guidewire lumen.

The balloon catheter according to the embodiment of the present invention is preferably any one of the following [2] to [12].
[2] The balloon catheter described in [1], wherein, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion, the first lumen is located on a line segment connecting the centroid of the guidewire lumen and the centroid of the second lumen.
[3] The balloon catheter described in [1], wherein, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion, the first lumen is not located on the line segment connecting the centroid of the guidewire lumen and the centroid of the second lumen.
[4] The balloon catheter according to any one of [1] to [3], wherein in a cross section perpendicular to the longitudinal direction of the proximal shaft portion, the centroid of the guidewire lumen is offset from the centroid of the proximal shaft portion.
[5] The balloon catheter according to any one of [1] to [4], wherein in a cross section perpendicular to the longitudinal direction of the proximal shaft portion, the outer shape of the first lumen is different from the outer shape of the second lumen.
[6] The balloon catheter according to any one of [1] to [5], wherein in a cross section perpendicular to the longitudinal direction of the proximal shaft portion, the outer shape of the first lumen is irregular.
[7] The balloon catheter according to any one of [1] to [6], wherein in a cross section perpendicular to the longitudinal direction of the proximal shaft portion, the cross-sectional area of the first lumen is larger than the cross-sectional area of the second lumen.
[8] The balloon catheter according to any one of [1] to [6], wherein in a cross-section perpendicular to the longitudinal direction of the proximal shaft portion, the cross-sectional area of the second lumen is larger than the cross-sectional area of the first lumen.
[9] The balloon catheter has a proximal sleeve portion connecting the balloon portion and the proximal shaft portion,
The balloon catheter according to any one of claims [1] to [8], wherein the proximal sleeve portion has a flow path through which a fluid can pass.
[10] A distal shaft portion located distal to the balloon portion;
The balloon catheter according to any one of [1] to [9], further comprising a distal sleeve portion connecting the balloon portion and the distal shaft portion.
[11] The balloon catheter according to [10], wherein the distal sleeve portion has a flow path through which a fluid can pass.
[12] The balloon catheter according to [10], wherein the distal sleeve portion does not have a flow path through which a fluid can pass.

The balloon catheter according to the embodiment of the present invention can easily prevent fluid from leaking from the second lumen into the guidewire lumen.

FIG. 1 is a side view of a balloon catheter according to an embodiment of the present invention. FIG. 2 is an enlarged side view of the balloon portions of the balloon catheter shown in FIG. FIG. 3 is a cross-sectional end view taken along line III-III shown in FIG. FIG. 4 is a cross-sectional end view taken along line IV-IV shown in FIG. FIG. 5 is a cutaway end view showing a modification of the balloon catheter shown in FIG. FIG. 6 is a cutaway end view showing a modification of the balloon catheter shown in FIG. FIG. 7 is a side view showing a modification of the balloon portion group shown in FIG. FIG. 8 is an enlarged cross-sectional view of the balloon portion, the distal sleeve portion, and the proximal sleeve portion of the balloon catheter shown in FIG. FIG. 9 is a cross-sectional view showing a modification of the balloon portion, the distal sleeve portion, and the proximal sleeve portion shown in FIG. FIG. 10 is a cross-sectional end view taken along line XX shown in FIG. FIG. 11 is a cutaway end view showing a modification of the balloon catheter shown in FIG. FIG. 12 is a cutaway end view showing a modification of the balloon catheter shown in FIG. FIG. 13 is a cutaway end view showing a modification of the balloon catheter shown in FIG.

The present invention will be described in detail below with reference to the drawings, but the present invention is of course not limited to the illustrated examples, and can be implemented with appropriate modifications within the scope of the intent described above and below, all of which are included in the technical scope of the present invention. Hatching and symbols may be omitted in each figure for convenience, but in such cases, reference should be made to the specification or other figures. Furthermore, the dimensions of various parts in the drawings may differ from the actual dimensions, as priority is given to aiding understanding of the features of the present invention.

One embodiment of the balloon catheter of the present invention has a balloon group including a plurality of balloon parts arranged in parallel, and a proximal shaft part located proximal to the balloon parts, the balloon group including an inner balloon part equipped with a guidewire tube into which a guidewire is inserted, and an outer balloon part located radially outward of the inner balloon part, the proximal shaft part has a guidewire lumen into which the guidewire is inserted, a first lumen through which a fluid supplied to the inner balloon part can pass, and a second lumen through which a fluid supplied to the outer balloon part can pass, and the gist is that in a cross section perpendicular to the longitudinal direction of the proximal shaft part, the distance between the centroid of the guidewire lumen and the centroid of the second lumen is longer than the distance between the centroid of the guidewire lumen and the centroid of the first lumen.

The overall configuration of a balloon catheter according to an embodiment of the present invention will be described with reference to Figures 1 to 13. These figures show a balloon catheter 100 that includes a balloon portion group 1 and a proximal shaft portion 3. In these figures, the longitudinal direction of the balloon catheter is indicated by x, the radial direction by y, and the circumferential direction by c.

The members and parts of the balloon catheter 100 each have a longitudinal direction, a radial direction, and a circumferential direction. The longitudinal direction, radial direction, and circumferential direction of the members and parts of the balloon catheter 100 may coincide with the longitudinal direction x, radial direction y, and circumferential direction c of the balloon catheter 100, or they may differ from each other. For ease of understanding, this specification shows an embodiment in which the longitudinal direction, radial direction, and circumferential direction of all members and parts other than the distal sleeve portion 4 and the proximal sleeve portion 5 coincide with the longitudinal direction x, radial direction y, and circumferential direction c of the balloon catheter 100, respectively.

In this specification, the proximal side refers to the direction toward the user's hand in the longitudinal direction x of the balloon catheter 100, and the distal side refers to the opposite side of the proximal side, i.e., the direction toward the treatment target. In addition, when each member or part is divided into two equal parts in the longitudinal direction x of the balloon catheter 100, the part located on the distal side of each member or part is referred to as the distal part of each member or part, and the part located on the proximal side of each member or part is referred to as the proximal part of each member or part. The distal end of each member or part is the end located on the most distal side of each member or part. The proximal end of each member or part is the end located on the most proximal side of each member or part. The end includes the peripheral part of the end. In other words, the distal end refers to the distal end and the peripheral part of the distal end, and the proximal end refers to the proximal end and the peripheral part of the proximal end.

FIG. 1 shows a side view of a balloon catheter according to an embodiment of the present invention. More specifically, FIG. 1 shows a state in which the balloon portion of the balloon catheter is expanded. FIG. 2 shows an enlarged side view of the balloon portions of the balloon catheter shown in FIG. 1. FIG. 3 shows an end view of a cut portion taken along line III-III in FIG. 2. FIG. 4 shows an end view of a cut portion taken along line IV-IV in FIG. 2. FIGS. 5 and 6 show end views of a cut portion showing a modified example of the balloon catheter shown in FIG. 4. FIG. 7 shows a side view showing a modified example of the balloon portions of the group shown in FIG. 2. FIG. 8 shows an enlarged cross-sectional view of the balloon portion, distal sleeve portion, and proximal sleeve portion of the balloon catheter shown in FIG. 1. FIG. 9 shows a cross-sectional view showing a modified example of the balloon portion, distal sleeve portion, and proximal sleeve portion shown in FIG. 8. More specifically, FIGS. 8 and 9 are cross-sectional views in a section passing through the central axis of the balloon portion and parallel to the longitudinal direction of the balloon catheter. Figure 10 shows a cross-sectional end view taken along line X-X in Figure 2. Figures 11 to 13 show cross-sectional end views illustrating modified examples of the balloon catheter shown in Figure 10.

As shown in Figures 1 and 2, the balloon catheter 100 has a balloon portion group 1 and a proximal shaft portion 3.

As shown in Figures 1 to 3 and 7, the balloon portion group 1 includes multiple balloon portions 10 arranged in parallel. It is preferable that the multiple balloon portions 10 are lined up in a direction perpendicular to the longitudinal direction x of the balloon catheter 100.

The balloon portion 10 is a portion that expands when a fluid is supplied thereto and contracts when the fluid is discharged therefrom. FIG. 3 shows a cut end surface of the balloon portion 10 in a direction perpendicular to the longitudinal direction x of the balloon catheter 100. FIGS. 8 and 9 show a cross section of the balloon portion 10 in a direction parallel to the longitudinal direction x of the balloon catheter 100. In order to control the expansion and contraction of the balloon portion 10, a configuration can be used in which a fluid is introduced or discharged using an indeflator (balloon pressurizer). For example, the fluid can be a gas such as nitrogen or air, or a liquid such as saline or a mixture of a contrast agent and saline. The fluid may be a pressurized fluid pressurized by a pump or the like.

As shown in FIG. 2, the balloon portion group 1 includes an inner balloon portion 11 equipped with a guidewire tube 13 into which a guidewire is inserted, and an outer balloon portion 12 located radially outward of the inner balloon portion 11. The inner balloon portion 11 refers to a balloon portion 10 among the multiple balloon portions 10 in which a guidewire tube 13 into which a guidewire is inserted is disposed. The outer balloon portion 12 refers to a balloon portion 10 among the multiple balloon portions 10 in which a guidewire tube 13 into which a guidewire is inserted is not disposed, and which is located radially outward of the inner balloon portion 11.

As shown in FIG. 1, the proximal shaft portion 3 is located proximally of the balloon portion 10.

As shown in Figures 4 to 6, the proximal shaft portion 3 has a guidewire lumen 30 into which a guidewire is inserted, a first lumen 31 through which fluid supplied to the inner balloon portion 11 can pass, and a second lumen 32 through which fluid supplied to the outer balloon portion 12 can pass. In a cross section perpendicular to the longitudinal direction x of the balloon catheter 100, the guidewire lumen 30, the first lumen 31, and the second lumen 32 are preferably formed in different regions. The guidewire lumen 30, the first lumen 31, and the second lumen 32 preferably extend in the longitudinal direction x of the balloon catheter 100.

As shown in Figures 4 to 6, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the distance between the centroid 30c of the guidewire lumen 30 and the centroid 32c of the second lumen 32 is configured to be longer than the distance between the centroid 30c of the guidewire lumen 30 and the centroid 31c of the first lumen 31.

By making the distance between the centroid 30c of the guidewire lumen 30 and the centroid 32c of the second lumen 32 longer than the distance between the centroid 30c of the guidewire lumen 30 and the centroid 31c of the first lumen 31, it is possible to prevent the portion between the second lumen 32 and the guidewire lumen 30 from becoming too thin due to the second lumen 32 coming too close to the guidewire lumen 30. This makes it easier to prevent fluid from leaking from the second lumen 32 into the guidewire lumen 30.

The balloon catheter 100 according to the embodiment of the present invention is preferably used to expand an aortic valve, deform a biological valve placed in the heart, or destroy a biological valve. Specifically, the balloon catheter 100 according to the embodiment of the present invention is preferably used for the purpose of expanding an aortic valve that has hardened due to calcification or the like, or for the purpose of deforming or destroying an artificial valve ring of a biological valve that is placed in the heart and is intended to replace a biological valve that has deteriorated over time.

The balloon catheter 100 has a distal end and a proximal end in its longitudinal direction x.

The number of balloon portions 10 included in balloon portion group 1 can be, for example, 2 or more, 3 or more, 4 or more, etc. The number of balloon portions 10 included in balloon portion group 1 can be, for example, 15 or less, 13 or less, 10 or less, etc. Figures 1 to 3 and 7 show an embodiment in which balloon portion group 1 includes 7 balloon portions 10.

As shown in Figures 2 and 7, the balloon portion 10 has a distal end 10d and a proximal end 10p in the longitudinal direction x of the balloon catheter 100. The distal end of the balloon portion group 1 coincides with the distal end 10d located most distally among the distal ends 10d owned by each of the multiple balloon portions 10. The proximal end of the balloon portion group 1 coincides with the proximal end 10p located most proximally among the proximal ends 10p owned by each of the multiple balloon portions 10.

Examples of materials that can be used to form the balloon portion 10 include polyamide resins such as nylon 11 and nylon 12, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polyurethane resins, thermoplastic elastomers such as polyether block amide copolymers, and combinations of these.

2, the balloon section 10 may have a straight tube section 10a, a distal tapered section 10b located distal to the straight tube section 10a and having a smaller outer diameter toward the distal side, and a proximal tapered section 10c located proximal to the straight tube section 10a and having a smaller outer diameter toward the proximal side. Only a portion of the multiple balloon sections 10 provided on the balloon catheter 100 may have the straight tube section 10a, the distal tapered section 10b, and the proximal tapered section 10c. All of the multiple balloon sections 10 provided on the balloon catheter 100 may have the straight tube section 10a, the distal tapered section 10b, and the proximal tapered section 10c.

The straight tube portion 10a may be a hollow cylinder having approximately the same diameter in the longitudinal direction x of the balloon catheter 100, or may have different diameters in the longitudinal direction x of the balloon catheter 100.

The distal tapered portion 10b and the proximal tapered portion 10c are preferably formed in a hollow cone shape or hollow truncated cone shape that tapers away from the straight tube portion 10a.

As shown in Figures 2 and 7, one inner balloon portion 11 has a distal end 11d and a proximal end 11p.

As shown in Figures 2 and 7, one outer balloon portion 12 has a distal end 12d and a proximal end 12p.

The number of inner balloon portions 11 can be, for example, 1 or more, 2 or more, 3 or more, etc. The number of inner balloon portions 11 can be, for example, 6 or less, 5 or less, 4 or less, etc. Figures 2, 3, and 7 show an embodiment in which only one inner balloon portion 11 is provided.

The number of outer balloon portions 12 can be, for example, 1 or more, 2 or more, 3 or more, etc. The number of outer balloon portions 12 can be, for example, 14 or less, 12 or less, 10 or less, etc. Figures 2, 3, and 7 show an embodiment in which six outer balloon portions 12 are provided.

When multiple outer balloon portions 12 are provided, it is preferable that all of the outer balloon portions 12 abut against the inner balloon portion 11. Note that it is also acceptable that some of the multiple outer balloon portions 12 abut against the inner balloon portion 11, and the remaining outer balloon portions 12 do not abut against the inner balloon portion 11. In other words, it is also acceptable that some of the multiple outer balloon portions 12 abut against the inner balloon portion 11, and the remaining outer balloon portions 12 do not abut against the inner balloon portion 11, but abut against other outer balloon portions 12.

The material constituting the inner balloon portion 11 and the material constituting the outer balloon portion 12 may be the same or different.

A plurality of outer balloon portions 12 may be arranged around the inner balloon portion 11. The inner balloon portion 11 may be located at a position where the central axis of the balloon portion group 1 passes through. The plurality of outer balloon portions 12 may be arranged in the circumferential direction c of the balloon catheter 100.

The guidewire tube 13 is inserted into the guidewire. The guidewire tube 13 has an inner cavity into which the guidewire is inserted. It is preferable that the inner cavity of the guidewire tube 13 extends in the longitudinal direction x of the balloon catheter 100.

The materials that can be used to construct the guidewire tube 13 include the materials exemplified for constructing the proximal shaft portion 3 described below.

The shape of the guidewire tube 13 can be cylindrical, hollow cylindrical, hollow polygonal prism, etc.

A radiopaque marker may be placed on the outer surface of the guidewire tube 13 at a position where the inner balloon portion 11 is located in the longitudinal direction x of the balloon catheter 100. The radiopaque marker is preferably placed on the outer surface of the guidewire tube 13 at a position where the distal end of the straight tube portion of the inner balloon portion 11 is located and at a position where the proximal end of the straight tube portion of the inner balloon portion 11 is located in the longitudinal direction x of the balloon catheter 100. The radiopaque marker may also be placed at a position where the center of the straight tube portion of the inner balloon portion 11 is located in the longitudinal direction x of the balloon catheter 100.

As shown in FIG. 2, the proximal end 11p of the inner balloon portion 11 may be located at the same position as the proximal end 12p of the outer balloon portion 12 in the longitudinal direction x of the balloon catheter 100. As shown in FIG. 7, the proximal end 11p of the inner balloon portion 11 may be located distal to the proximal end 12p of the outer balloon portion 12. Although not shown, a configuration in which the proximal end 11p of the inner balloon portion 11 is located proximal to the proximal end 12p of the outer balloon portion 12 is also acceptable.

As shown in FIG. 2, the distal end 11d of the inner balloon portion 11 may be located at the same position as the distal end 12d of the outer balloon portion 12 in the longitudinal direction x of the balloon catheter 100. As shown in FIG. 7, the distal end 11d of the inner balloon portion 11 may be located proximal to the distal end 12d of the outer balloon portion 12. Although not shown, the distal end 11d of the inner balloon portion 11 may be located distal to the distal end 12d of the outer balloon portion 12.

The proximal shaft portion 3 preferably extends in the longitudinal direction x of the balloon catheter 100.

The shape of the proximal shaft portion 3 can be cylindrical, hollow cylindrical, hollow polygonal prism, etc.

The proximal shaft section 3 may be, for example, a hollow body formed by arranging one or more wires in a predetermined pattern; a hollow body having at least one of the inner and outer surfaces coated with resin; a resin tube; or a combination of these, for example, a combination of these connected in the longitudinal direction. Examples of hollow bodies in which wires are arranged in a predetermined pattern include a tubular body having a mesh structure formed by crossing or weaving wires, and a coil in which wires are wound. The wires may be one or more solid wires, or one or more twisted wires. The resin tube may be manufactured by extrusion molding, for example. When the proximal shaft section 3 is a resin tube, the proximal shaft section 3 may be composed of a single layer or multiple layers. The proximal shaft section 3 may be composed of a single layer in a portion in the longitudinal direction x or circumferential direction c of the balloon catheter 100, and the other portion may be composed of multiple layers.

The proximal shaft portion 3 can be made of synthetic resins such as polyolefin resins (e.g., polyethylene and polypropylene), polyamide resins (e.g., nylon), polyester resins (e.g., PET), aromatic polyether ketone resins (e.g., PEEK), polyether polyamide resins, polyurethane resins, polyimide resins, and fluororesins (e.g., PTFE, PFA, and ETFE), or metals such as stainless steel, carbon steel, and nickel-titanium alloys. These may be used alone or in combination of two or more types.

The proximal shaft portion 3 may be made up of only one cylindrical member, or may be made up of multiple cylindrical members.

The guidewire lumen 30 is preferably connected to the inner cavity of the guidewire tube 13 disposed inside the inner balloon portion 11.

The first lumen 31 is preferably connected to the inside of the inner balloon portion 11. The inner balloon portion 11 is preferably expanded by fluid supplied through the first lumen 31. The inner balloon portion 11 is preferably contracted by discharging fluid through the first lumen 31.

There may be multiple first lumens 31, but it is preferable to have only one. It is preferable to have the same number of first lumens 31 as the number of inner balloon portions 11.

The second lumen 32 is preferably connected to the inside of the outer balloon portion 12. The outer balloon portion 12 is preferably expanded by fluid supplied through the second lumen 32. The outer balloon portion 12 is preferably contracted by discharging fluid through the second lumen 32.

Although only one second lumen 32 may be provided, it is preferable that multiple second lumens 32 are provided. It is preferable that the same number of second lumens 32 are provided as the outer balloon portion 12. In a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the distance between the centroid 30c of the guidewire lumen 30 and the centroid 32c of the second lumen 32 is longer than the distance between the centroid 30c of the guidewire lumen 30 and the centroid 31c of the first lumen 31, which makes it easier to arrange multiple second lumens 32 concentrically and at equal intervals.

In a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the second lumen 32 is preferably located radially outward of the proximal shaft portion 3 than the first lumen 31.

The outer shapes of the guidewire lumen 30, the first lumen 31, and the second lumen 32 in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3 may each be circular, polygonal including triangular and rectangular, semicircular, sector-shaped, wedge-shaped, convex, crescent-shaped, or a combination of these.

As shown in Figures 5 and 6, the outer shape of the first lumen 31 in a cross section perpendicular to the longitudinal direction of the proximal shaft section 3 may have a different shape from the outer shape of the second lumen 32. In a cross section perpendicular to the longitudinal direction of the proximal shaft section 3, the outer shape of the first lumen 31 may have a different shape from the outer shape of the guidewire lumen 30. In a cross section perpendicular to the longitudinal direction of the proximal shaft section 3, the outer shape of the second lumen 32 may have a different shape from the outer shape of the guidewire lumen 30. In a cross section perpendicular to the longitudinal direction of the proximal shaft section 3, the outer shape of the first lumen 31, the outer shape of the second lumen 32, and the outer diameter of the guidewire lumen 30 may each have a different shape. This configuration makes it easier to reduce the diameter of the proximal shaft section 3.

As shown in Figures 5 and 6, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, it is preferable that the outer shape of the first lumen 31 is irregular. Irregular shape means a shape other than a perfect circle, and shapes such as an ellipse or egg shape are not included in the perfect circle. Note that although the term "circular shape" may be used in this specification, the circular shape includes shapes such as a perfect circle, an ellipse, and an egg shape.

As shown in FIG. 5, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the cross-sectional area of the first lumen 31 may be larger than the cross-sectional area of the second lumen 32. This makes it easier to expand the inner balloon portion 11 at an earlier timing than the outer balloon portion 12.

As shown in FIG. 4, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the cross-sectional area of the second lumen 32 may be larger than the cross-sectional area of the first lumen 31. This makes it easier to expand the outer balloon portion 12 at an earlier timing than the inner balloon portion 11.

Although not shown, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the cross-sectional area of the first lumen 31 and the cross-sectional area of the second lumen 32 may be the same. This makes it easier to expand the inner balloon portion 11 and the outer balloon portion 12 simultaneously.

As shown in Figures 2, 4, and 6, the proximal shaft portion 3 may have an outer tube 33 having an inner lumen 331 extending in the longitudinal direction x of the balloon catheter 100, a first tube 34 disposed in the inner lumen 331 of the outer tube 33, and a second tube 35 disposed in the inner lumen 331 of the outer tube 33. The second tube 35 is preferably located radially outward of the first tube 34. In a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the second tube 35 is preferably located radially outward of the proximal shaft portion 3 than the first tube 34.

The material constituting the outer tube 33, the material constituting the first tube 34, and the material constituting the second tube 35 may be the same or different.

It is preferable that the first tube 34 has a guidewire lumen 30 and a first lumen 31 formed therein, and the second tube 35 has a second lumen 32 formed therein.

Although multiple first tubes 34 may be provided, it is preferable that there is only one. It is preferable that the same number of first tubes 34 as the number of inner balloon portions 11 are provided. It is also preferable that the distal end of the first tube 34 is connected to the proximal end of the proximal sleeve portion 5 connected to the inner balloon portion 11. This allows fluid to be supplied to the inside of the inner balloon portion 11 via the first lumen 31 of the first tube 34 and the flow path 6 of the proximal sleeve portion 5 described below.

Although only one second tube 35 may be provided, it is preferable that multiple second tubes 35 are provided. It is preferable that the same number of second tubes 35 as the outer balloon portion 12 are provided. It is also preferable that the distal end of the second tube 35 is connected to the proximal end of the proximal sleeve portion 5 connected to the outer balloon portion 12. This allows fluid to be supplied to the inside of the outer balloon portion 12 via the second lumen 32 of the second tube 35 and the flow path 6 of the proximal sleeve portion 5.

As shown in FIG. 6, a filler 36 may be disposed in the space surrounded by the inner surface of the outer tube 33, the outer surface of the first tube 34, and the outer surface of the second tube 35.

The filler 36 can be any of the materials exemplified as the materials constituting the balloon portion 10 and the proximal shaft portion 3.

As shown in FIG. 4, a gap may exist in the space surrounded by the inner surface of the outer tube 33, the outer surface of the first tube 34, and the outer surface of the second tube 35. The inner surface of the outer tube 33, the outer surface of the first tube 34, and the outer surface of the second tube 35 may be exposed to the gap.

As shown in FIG. 5, the proximal shaft portion 3 may be formed of a tubular member 37 having a guidewire lumen 30 through which a guidewire is inserted, a first lumen 31 through which the fluid supplied to the inner balloon portion 11 can pass, and a second lumen 32 through which the fluid supplied to the outer balloon portion 12 can pass. In this case, it is preferable that the proximal end of the proximal sleeve portion 5 connected to the inner balloon portion 11 is connected to the distal end of the proximal shaft portion 3 so that the flow path 6 of the proximal sleeve portion 5 connected to the inner balloon portion 11 is connected to the first lumen 31. It is also preferable that the proximal end of the proximal sleeve portion 5 connected to the outer balloon portion 12 is connected to the distal end of the proximal shaft portion 3 so that the flow path 6 of the proximal sleeve portion 5 connected to the outer balloon portion 12 is connected to the second lumen 32. With the above configuration, a fluid can be supplied to the inside of the inner balloon portion 11 through the first lumen 31 and the flow path 6 of the proximal sleeve portion 5. In addition, fluid can be supplied to the inside of the outer balloon portion 12 via the second lumen 32 and the flow path 6 of the proximal sleeve portion 5.

As shown in Figures 5 and 6, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the first lumen 31 may be present on a line segment connecting the centroid 30c of the guidewire lumen 30 and the centroid 32c of the second lumen 32. In Figures 5 and 6, the line segment connecting the centroid 30c of the guidewire lumen 30 and the centroid 32c of the second lumen 32 is depicted by a dashed line. This allows the cross-sectional area of the first lumen 31 in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3 to be relatively large, making it easier to expand the inner balloon portion 11 at an earlier timing than the outer balloon portion 12.

As shown in FIG. 4, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the first lumen 31 may not be present on the line segment connecting the centroid 30c of the guidewire lumen 30 and the centroid 32c of the second lumen 32. More specifically, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the first lumen 31 may be present between two line segments connecting the centroid 30c of the guidewire lumen 30 and the centroid 32c of the second lumen 32, which are adjacent to each other in the circumferential direction c of the balloon catheter 100. In FIG. 4, the line segment connecting the centroid 30c of the guidewire lumen 30 and the centroid 32c of the second lumen 32 is depicted by a dashed line. This allows the cross-sectional area of the first lumen 31 in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3 to be relatively small, making it easier to expand the outer balloon portion 12 at an earlier timing than the inner balloon portion 11.

As shown in Figures 4 to 6, in a cross section perpendicular to the longitudinal direction of the proximal shaft section 3, the centroid 30c of the guidewire lumen 30 may be offset from the centroid 3c of the proximal shaft section 3. Although not shown, a configuration in which the centroid 30c of the guidewire lumen 30 coincides with the centroid 3c of the proximal shaft section 3 in a cross section perpendicular to the longitudinal direction of the proximal shaft section 3 is also acceptable. In a cross section perpendicular to the longitudinal direction of the proximal shaft section 3, it is preferable that the guidewire lumen 30 is formed in a region including the centroid 3c of the proximal shaft section 3.

As shown in Figures 1, 2, and 7, the balloon catheter 100 may have a proximal sleeve portion 5 that connects the balloon portion 10 and the proximal shaft portion 3.

Although multiple proximal sleeve portions 5 may be connected to one balloon portion 10, it is preferable that only one proximal sleeve portion 5 is connected to one balloon portion 10.

It is preferable that multiple proximal sleeve portions 5 are connected to one proximal shaft portion 3.

It is preferable that one proximal sleeve portion 5 is connected to one balloon portion 10, and it is more preferable that the distal end portion of one proximal sleeve portion 5 is connected to the proximal end portion of one balloon portion 10. It is also preferable that one proximal shaft portion 3 is connected to multiple proximal sleeve portions 5, and it is more preferable that the distal end portion of one proximal shaft portion 3 is connected to the proximal end portions of multiple proximal sleeve portions 5.

As shown in Figures 8 and 9, the proximal sleeve portion 5 preferably has a flow path 6 through which a fluid can pass. Although not shown in detail, the flow path 6 preferably connects from the distal end to the proximal end of the proximal sleeve portion 5. This allows fluid to be supplied to the inside of the balloon portion 10 via the flow path 6 of the proximal sleeve portion 5.

The shape of the proximal sleeve portion 5 can be cylindrical, hollow cylindrical, hollow polygonal prism, etc.

The materials used to form the proximal sleeve portion 5 can be the same as those exemplified as the materials used to form the balloon portion 10 and the proximal shaft portion 3.

As shown in Figures 1, 2, and 7, the balloon catheter 100 may have a distal shaft portion 2 located distal to the balloon portion 10.

As shown in FIG. 1, the distal shaft portion 2 is located distal to the balloon portion 10.

The distal shaft portion 2 preferably extends in the longitudinal direction x of the balloon catheter 100. The distal shaft portion 2 may have a lumen through which the fluid can pass after being supplied to the balloon portion 10, or may not have a lumen through which the fluid can pass after being supplied to the balloon portion 10.

The shape of the distal shaft portion 2 can be cylindrical, hollow cylindrical, hollow polygonal cylindrical, conical, truncated conical, tapered, etc.

As shown in FIG. 1, in the longitudinal direction x of the balloon catheter 100, it is preferable that the length of the distal shaft portion 2 is shorter than the length of the proximal shaft portion 3.

The materials exemplified as materials for constructing the proximal shaft portion 3 can be used as materials for constructing the distal shaft portion 2.

10 to 13, the distal shaft section 2 may have a guidewire lumen 20 into which the guidewire is inserted. As shown in FIGS. 10 to 12, the distal shaft section 2 may have a guidewire lumen 20 into which the guidewire is inserted, a first lumen 21 through which the fluid can pass after being supplied to the inner balloon section 11, and a second lumen 22 through which the fluid can pass after being supplied to the outer balloon section 12. In this case, in a cross section perpendicular to the longitudinal direction x of the balloon catheter 100, the guidewire lumen 20, the first lumen 21, and the second lumen 22 are preferably formed in different regions. From the viewpoint of ease of diameter reduction, it is preferable that the distal shaft section 2 has only the guidewire lumen 20 into which the guidewire is inserted, as shown in FIG. 13. It is preferable that the guidewire lumen 20, the first lumen 21, and the second lumen 22 extend in the longitudinal direction x of the balloon catheter 100.

It is preferable that the guidewire lumen 20 is connected to the inner cavity of the guidewire tube 13 disposed inside the inner balloon portion 11.

The first lumen 21 may be connected to the inside of the inner balloon portion 11.

There may be multiple first lumens 21, or there may be only one. The number of first lumens 21 may be the same as the number of inner balloon portions 11.

The second lumen 22 may be connected to the inside of the outer balloon portion 12.

There may be only one second lumen 22, but multiple second lumens 22 may also be provided. The number of second lumens 22 may be the same as the number of outer balloon portions 12.

In a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, the second lumen 22 is preferably located radially outward of the proximal shaft portion 3 than the first lumen 21.

The outer shapes of the guidewire lumen 20, the first lumen 21, and the second lumen 22 in a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3 may each be circular, polygonal including triangular and rectangular, semicircular, sectoral, wedge-shaped, convex, crescent, or a combination of these.

As shown in Figures 2, 10, and 12, the distal shaft portion 2 may have an outer tube 23 having a lumen 231 extending in the longitudinal direction x of the balloon catheter 100, a first tube 24 disposed in the lumen 231 of the outer tube 23, and a second tube 25 disposed in the lumen 231 of the outer tube 23. In a cross section perpendicular to the longitudinal direction of the proximal shaft portion 3, it is preferable that the second tube 25 is located radially outward of the proximal shaft portion 3 relative to the first tube 24.

The material constituting the outer tube 23, the material constituting the first tube 24, and the material constituting the second tube 25 may be the same or different.

The first tube 24 may have a guidewire lumen 20 and a first lumen 21 formed therein, and the second tube 25 may have a second lumen 22 formed therein.

There may be multiple first tubes 24, or only one. The number of first tubes 24 may be the same as the number of inner balloon portions 11. The proximal end of the first tube 24 may be connected to the distal end of the distal sleeve portion 4 connected to the inner balloon portion 11. This allows fluid to be supplied from the inner balloon portion 11 to the first lumen 21 of the first tube 24 via the flow path 6 of the distal sleeve portion 4, which will be described later.

There may be only one second tube 25, or multiple second tubes 25. The number of second tubes 25 may be the same as the number of outer balloon portions 12. The proximal end of the second tube 25 may be connected to the distal end of the distal sleeve portion 4 connected to the outer balloon portion 12. This allows fluid to be supplied from the outer balloon portion 12 to the second lumen 22 of the second tube 25 via the flow path 6 of the distal sleeve portion 4.

As shown in FIG. 12, a filler 26 may be disposed in the space surrounded by the inner surface of the outer tube 23, the outer surface of the first tube 24, and the outer surface of the second tube 25.

The filler 26 can be any of the materials exemplified as the materials constituting the balloon portion 10 and the proximal shaft portion 3.

As shown in FIG. 10, a gap may exist in the space surrounded by the inner surface of the outer tube 23, the outer surface of the first tube 24, and the outer surface of the second tube 25. The inner surface of the outer tube 23, the outer surface of the first tube 24, and the outer surface of the second tube 25 may be exposed to the gap.

As shown in FIG. 11, the distal shaft portion 2 may be formed of a tubular member 27 having a guidewire lumen 20 into which a guidewire is inserted, a first lumen 21 through which the fluid supplied to the inner balloon portion 11 can pass, and a second lumen 22 through which the fluid supplied to the outer balloon portion 12 can pass. In this case, the distal end of the distal sleeve portion 4 connected to the inner balloon portion 11 may be connected to the proximal end of the distal shaft portion 2 so that the flow path 6 of the distal sleeve portion 4 connected to the inner balloon portion 11 communicates with the first lumen 21. It is preferable that the distal end of the distal sleeve portion 4 connected to the outer balloon portion 12 is connected to the proximal end of the distal shaft portion 2 so that the flow path 6 of the distal sleeve portion 4 connected to the outer balloon portion 12 communicates with the second lumen 22. With the above configuration, the fluid supplied to the inner balloon portion 11 is supplied to the first lumen 21 through the flow path 6 of the distal sleeve portion 4. In addition, the fluid supplied to the outer balloon portion 12 is supplied to the second lumen 22 via the flow path 6 of the distal sleeve portion 4.

The guidewire lumen 20 preferably penetrates the balloon catheter 100 in the longitudinal direction x.

The first lumen 21 and the second lumen 22 are preferably open at the proximal end and closed at the distal end. In other words, it is preferable that no fluid is supplied distal to the distal shaft portion 2. This makes it easier for fluid to accumulate inside the balloon portion 10, making it easier for the balloon portion 10 to expand.

As shown in Figures 1, 2, and 7, the balloon catheter 100 may have a distal sleeve portion 4 that connects the balloon portion 10 and the distal shaft portion 2.

Although multiple distal sleeve portions 4 may be connected to one balloon portion 10, it is preferable that only one distal sleeve portion 4 is connected to one balloon portion 10.

It is preferable that multiple distal sleeve portions 4 are connected to one distal shaft portion 2.

It is preferable that one distal sleeve portion 4 is connected to one balloon portion 10, and it is more preferable that the proximal end portion of one distal sleeve portion 4 is connected to the distal end portion of one balloon portion 10. It is preferable that one distal shaft portion 2 is connected to multiple distal sleeve portions 4, and it is more preferable that the proximal end portion of one distal shaft portion 2 is connected to the distal ends of multiple distal sleeve portions 4.

As shown in FIG. 8, the distal sleeve portion 4 may have a flow path 6 through which a fluid can pass. Although not shown in detail, the flow path 6 may be connected from the distal end to the proximal end of the distal sleeve portion 4. The flow path 6 may be present only in a portion of the distal end to the proximal end of the distal sleeve portion 4.

As shown in FIG. 9, the distal sleeve portion 4 does not have to have a flow path 6 through which a fluid can pass. This makes it easier to make the distal sleeve portion 4 thinner.

The shape of the distal sleeve portion 4 can be cylindrical, polygonal, tubular, hollow cylindrical, hollow polygonal, etc.

The materials used to form the distal sleeve portion 4 can be the same as those exemplified as the materials used to form the balloon portion 10 and the proximal shaft portion 3.

As shown in FIG. 1, a hub 7 may be connected to the proximal portion of the proximal shaft portion 3. Although not shown, the hub 7 may have a bifurcated structure. The hub 7 may also be provided with a fluid injection portion 8 capable of injecting a fluid to be supplied to the inside of the balloon portion 10. The fluid injection portion 8 is preferably connected to the indeflator described above.

The proximal shaft portion 3 and the hub 7 may be fixed to each other. For example, the proximal shaft portion 3 and the hub 7 can be fixed to each other by adhesive bonding, welding, screws, or the like. In particular, it is preferable that the proximal shaft portion 3 and the hub 7 are fixed to each other by adhesive bonding. By fixing the proximal shaft portion 3 and the hub 7 to each other by adhesive bonding, the strength of the connection between the proximal shaft portion 3 and the hub 7 can be increased when the proximal shaft portion 3 and the hub 7 are made of different materials, for example, when the proximal shaft portion 3 is made of a highly flexible material and the hub 7 is made of a highly rigid material, and the like, this makes it easier to improve the durability of the balloon catheter 100.

FIG. 1 shows an embodiment in which a guidewire port 9 is formed on the way from the distal end to the proximal end of the proximal shaft portion 3. The guidewire port 9 is connected to the guidewire lumen 30 of the proximal shaft portion 3. FIG. 1 shows a so-called rapid exchange type balloon catheter 100. The proximal shaft portion 3 may have a first proximal shaft portion 3a and a second proximal shaft portion 3b located distal to the first proximal shaft portion 3a. The first proximal shaft portion 3a and the second proximal shaft portion 3b may be separate members, and the distal end of the member constituting the first proximal shaft portion 3a may be connected to the proximal end of the member constituting the second proximal shaft portion 3b. Alternatively, the first proximal shaft portion 3a and the second proximal shaft portion 3b may be formed by a single member.

As shown in FIG. 2, the proximal end of the guidewire tube 13 is preferably connected to the distal end of the proximal shaft portion 3. The proximal end of the guidewire tube 13 and the distal end of the proximal shaft portion 3 may be directly connected without any other member, or may be indirectly connected via another member. When the proximal shaft portion 3 has a first proximal shaft portion 3a and a second proximal shaft portion 3b, the proximal end of the guidewire tube 13 is preferably connected to the distal end of the second proximal shaft portion 3b.

As shown in FIG. 2, the distal end of the guidewire tube 13 is preferably connected to the proximal end of the distal shaft portion 2. The distal end of the guidewire tube 13 and the proximal end of the distal shaft portion 2 may be connected directly without using any other member, or indirectly via another member.

Although not shown, the balloon catheter 100 can be of the so-called over-the-wire type in which the guidewire lumen 30 is formed from the distal end to the proximal end of the proximal shaft portion 3. When the balloon catheter 100 is of the over-the-wire type, it is preferable that the guidewire lumen 30 of the proximal shaft portion 3 extends to the position where the hub 7 is located in the longitudinal direction x of the balloon catheter 100. It is preferable that the first lumen 31 and the second lumen 32 of the proximal shaft portion 3 extend halfway from the distal end to the proximal end of the proximal shaft portion 3. It is preferable that the proximal end of the first lumen 31 and the proximal end of the second lumen 32 of the proximal shaft portion 3 are located distal to the distal end of the hub 7. It is also preferable that the first lumen 31 and the second lumen 32 of the proximal shaft portion 3 extend to the position where the hub 7 is located in the longitudinal direction x of the balloon catheter 100.

The outer surface of the proximal shaft portion 3 and the outer surface of the distal shaft portion 2 may be coated. As shown in FIG. 1, when the balloon catheter 100 is of a rapid exchange type, the outer surface of at least one of the first proximal shaft portion 3a and the second proximal shaft portion 3b may be coated, or the outer surfaces of both the first proximal shaft portion 3a and the second proximal shaft portion 3b may be coated. When the balloon catheter 100 is of an over-the-wire type, only a part or the entire outer surface of the proximal shaft portion 3 may be coated. Only a part or the entire outer surface of the distal shaft portion 2 may be coated.

The coating applied to the outer surface of the proximal shaft portion 3 and the outer surface of the distal shaft portion 2 can be a hydrophilic coating or a hydrophobic coating depending on the purpose. The coating can be applied by immersing the proximal shaft portion 3 and the distal shaft portion 2 in a hydrophilic coating agent or a hydrophobic coating agent, by applying a hydrophilic coating agent or a hydrophobic coating agent to the outer surface of the proximal shaft portion 3 and the outer surface of the distal shaft portion 2, or by covering the outer surface of the proximal shaft portion 3 and the outer surface of the distal shaft portion 2 with a hydrophilic coating agent or a hydrophobic coating agent. Drugs and additives may be added to the coating agent.

Hydrophilic coating agents include hydrophilic polymers such as polyvinyl alcohol, polyethylene glycol, polyacrylamide, polyvinylpyrrolidone, methyl vinyl ether maleic anhydride copolymer, and hydrophilic coating agents composed of combinations of these.

Hydrophobic coating agents include polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), perfluoroalkoxyalkane (PFA), silicone oil, hydrophobic urethane resin, carbon coat, diamond coat, diamond-like carbon (DLC) coat, ceramic coat, and substances with low surface free energy terminated with alkyl groups or perfluoroalkyl groups.

This application claims the benefit of priority based on Japanese Patent Application No. 2024-003248, filed on January 12, 2024. The entire contents of the specification of Japanese Patent Application No. 2024-003248, filed on January 12, 2024, are incorporated by reference into this application.

1: Balloon section group 10: Balloon section 10a: Straight tube section 10b: Distal taper section 10c: Proximal taper section 10d: Distal end 10p: Proximal end 11: Inner balloon section 11d: Distal end 11p: Proximal end 12: Outer balloon section 12d: Distal end 12p: Proximal end 13: Guidewire tube 2: Distal shaft section 20: Guidewire lumen 21: First lumen 22: Second lumen 23: Outer tube 231: Inner cavity 24: First tube 25: Second tube 26: Filler 27: Cylindrical member 3: Proximal shaft section 3a: First proximal shaft section 3b: Second proximal shaft section Lift portion 3c: centroid 30 of proximal shaft portion: Guidewire lumen 30c: centroid 31 of guidewire lumen: First lumen 31c: centroid 32 of first lumen: Second lumen 32c: centroid 33 of second lumen: Outer tube 331: Inner cavity 34: First tube 35: Second tube 36: Filler 37: Cylindrical member 4: Distal sleeve portion 5: Proximal sleeve portion 6: Flow path 7: Hub 8: Fluid injection portion 9: Guidewire port 100: Balloon catheter x: Longitudinal direction of balloon catheter y: Radial direction of balloon catheter c: Circumferential direction of balloon catheter

Claims (12)

A balloon group including a plurality of balloon portions arranged side by side;
a proximal shaft portion located proximal to the balloon portion,
The balloon portion group includes an inner balloon portion having a guidewire tube into which a guidewire is inserted, and an outer balloon portion located radially outward of the inner balloon portion,
the proximal shaft portion has a guidewire lumen into which the guidewire is inserted, a first lumen through which a fluid supplied to the inner balloon portion can pass, and a second lumen through which a fluid supplied to the outer balloon portion can pass,
A balloon catheter, in which, in a cross section perpendicular to the longitudinal direction of the proximal shaft portion, the distance between the centroid of the guidewire lumen and the centroid of the second lumen is longer than the distance between the centroid of the guidewire lumen and the centroid of the first lumen. The balloon catheter according to claim 1, wherein the first lumen is located on a line segment connecting the centroid of the guidewire lumen and the centroid of the second lumen in a cross section perpendicular to the longitudinal direction of the proximal shaft portion. The balloon catheter according to claim 1, wherein in a cross section perpendicular to the longitudinal direction of the proximal shaft portion, the first lumen is not located on a line segment connecting the centroid of the guidewire lumen and the centroid of the second lumen. The balloon catheter according to claim 1, wherein in a cross section perpendicular to the longitudinal direction of the proximal shaft portion, the centroid of the guidewire lumen is offset from the centroid of the proximal shaft portion. The balloon catheter according to claim 1, wherein the outer shape of the first lumen is different from the outer shape of the second lumen in a cross section perpendicular to the longitudinal direction of the proximal shaft portion. The balloon catheter according to claim 1, wherein the outer shape of the first lumen is irregular in a cross section perpendicular to the longitudinal direction of the proximal shaft portion. The balloon catheter of claim 1, wherein the cross-sectional area of the first lumen is greater than the cross-sectional area of the second lumen in a cross section perpendicular to the longitudinal direction of the proximal shaft portion. The balloon catheter of claim 1, wherein the cross-sectional area of the second lumen is greater than the cross-sectional area of the first lumen in a cross section perpendicular to the longitudinal direction of the proximal shaft portion. the balloon catheter has a proximal sleeve portion connecting the balloon portion and the proximal shaft portion;
The balloon catheter according to claim 1 , wherein the proximal sleeve portion has a flow path through which a fluid can pass. a distal shaft portion located distal to the balloon portion;
The balloon catheter according to any one of claims 1 to 9, further comprising a distal sleeve portion connecting the balloon portion and the distal shaft portion. The balloon catheter according to claim 10, wherein the distal sleeve portion has a flow path through which a fluid can pass. The balloon catheter according to claim 10, wherein the distal sleeve portion does not have a flow path through which a fluid can pass.