Balloon for balloon catheter

Abstract

To provide a balloon for a balloon catheter which can be smoothly inserted into a body cavity and has improved trackability and pushability while increasing the strength of the balloon to prevent stretching in undesired directions and breakage of the balloon. [Solution] The balloon has protruding portions (60) that protrude radially outward beyond the outer surface of the balloon body (20) and extend in the longitudinal direction of the balloon body (20). In a radial cross section, the protruding portions (60) provided on the straight tube portion have a base end (61) that connects with the outer surface of the balloon body (20) and a tip end (62) that is located radially outward from the base end (61) and is the radially outer end of the protruding portion (60). The protruding portions (60) provided on the proximal tapered portion and / or the distal tapered portion are inclined in a first direction (d1) or a second direction (d2) in the circumferential direction of the balloon body (20). A straight line L connecting the midpoint of the width direction of the base end (61) and the tip end (62) is formed. p and the perpendicular line L of the base end 61 v The angle θ between the convex portions is 30° or more.

Description

Technical Field

[0001] The present invention relates to a balloon for a balloon catheter.

Background Art

[0002] When a stenosis hardened by calcification or the like is formed on the inner wall of a blood vessel, diseases such as angina pectoris and myocardial infarction are caused. As one of the treatments for these, there is an angioplasty in which a stenosis is expanded using a balloon catheter. Angioplasty is a minimally invasive treatment that does not require an open-chest operation such as bypass surgery and is widely performed.

[0003] A balloon catheter is inserted into a body cavity in a contracted state of the balloon and delivered through the body cavity to a treatment site. At the time of delivery, the conveyance of the balloon is controlled by transmitting an operation from the proximal side to the distal side where the balloon is disposed. At this time, it is required that the insertion through the body cavity is easy and that the transmission of the operation from the proximal side to the distal side is easy (high pushability). Further, when a fluid is introduced into the lumen of the balloon to expand the balloon, there are problems that the balloon extends in an undesired direction due to the pressure of the fluid or the balloon is damaged. In response to such problems, for example, Patent Document 1 discloses a balloon catheter in which the fixing strength between the balloon and the outer shaft is improved without increasing the outer diameter at the fixing portion between the balloon and the outer shaft.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Balloon catheters are required not only to have high pushability and balloon strength, but also the ability to smoothly insert into the body cavity and the ability to flexibly advance following the tortuous body cavity (trackability). However, conventional balloon catheters have been insufficient to achieve both improved strength and smooth insertion and improved trackability. Therefore, an object of the present invention is to provide a balloon for a balloon catheter that has increased balloon strength to prevent elongation and breakage of the balloon in an undesired direction, and that can smoothly insert into the body cavity and has improved trackability and pushability.

Means for Solving the Problems

[0006] The balloon for a balloon catheter according to an embodiment of the present invention is as follows. [1] A balloon for a balloon catheter having a straight tube portion, a proximal tapered portion located proximal to the straight tube portion, a proximal sleeve portion located proximal to the proximal tapered portion, a distal tapered portion located distal to the straight tube portion, and a distal sleeve portion located distal to the distal tapered portion, the balloon having a balloon body having an outer surface and an inner surface, and a protruding portion protruding radially outward from the outer surface of the balloon body and extending in the longitudinal axis direction of the balloon body, wherein in the radial cross-section, the protruding portion provided in the straight tube portion has a proximal end connected to the outer surface of the balloon body, and a distal end located radially outward of the proximal end and being the radially outer end of the protruding portion, and satisfying at least one of the following (1) and (2). (1) In the radial cross-section, the protruding portion of the proximal tapered portion is tilted in a first direction or a second direction in the circumferential direction of the balloon body, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 30° or more. (2) In the radial cross-section, the protruding portion of the distal tapered portion is inclined in the first direction or the second direction in the circumferential direction of the balloon body, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the tip end and the perpendicular line to the proximal end is 30° or more.

[0007] The balloon for a balloon catheter according to an embodiment of the present invention is preferably any one of the following [2] to [4]. [2] The balloon for a balloon catheter according to [1], satisfying at least one of the following (3) and (4). (3) In the radial cross-section, the protruding portion of the proximal tapered portion is inclined in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the tip end and the perpendicular line to the proximal end is 30° or more, the proximal sleeve portion and the proximal tapered portion have an inner protruding portion that protrudes inward in the radial direction from the inner surface of the balloon body and extends in the longitudinal axis direction. (4) In the radial cross-section, the protruding portion of the distal tapered portion is inclined in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the tip end and the perpendicular line to the proximal end is 30° or more, the distal sleeve portion and the distal tapered portion have an inner protruding portion that protrudes inward in the radial direction from the inner surface of the balloon body and extends in the longitudinal axis direction. [3] The balloon for a balloon catheter according to [1] or [2], satisfying at least one of the following (5) and (6). (5) In the radial cross-section, the protruding portion of the proximal tapered portion is inclined in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the tip end and the perpendicular line to the proximal end is 30° or more, the protruding portion is inclined in the first direction or the second direction throughout the longitudinal axis direction of the proximal tapered portion. (6) In the radial cross-section, the protruding portion of the distal tapered portion is tilted in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the tip and the perpendicular line to the proximal end is 30° or more. The protruding portion is tilted in the first direction or the second direction throughout the entire length in the longitudinal axis direction of the distal tapered portion. [4] The balloon for a balloon catheter according to [1] or [2], satisfying at least one of the following (7) and (8). (7) In the radial cross-section, the protruding portion of the proximal tapered portion is tilted in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the tip and the perpendicular line to the proximal end is 30° or more. The protruding portion is tilted in the first direction or the second direction in at least a part of the longitudinal axis direction of the proximal tapered portion. (8) In the radial cross-section, the protruding portion of the distal tapered portion is tilted in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the tip and the perpendicular line to the proximal end is 30° or more. The protruding portion is tilted in the first direction or the second direction in at least a part of the longitudinal axis direction of the distal tapered portion.

[0008] The present invention also provides the following. [5] A catheter provided with the balloon for a balloon catheter according to any one of [1] to [4] above.

Effects of the Invention

[0009] According to the balloon for the balloon catheter described above, by having the protrusions, the strength of the balloon is increased to prevent the balloon from stretching or breaking in an undesired direction, and when the balloon is moved forward or backward, the distal tapered portion and / or the proximal tapered portion that serve as the leading ends are provided with protrusions that fall in the first direction or the second direction in the circumferential direction of the balloon body. As a result, the fallen protrusions act like a cushion, enabling smooth insertion into the body cavity and improving the trackability of the balloon catheter. In addition, since the protrusions provided on the distal tapered portion and / or the proximal tapered portion fall in the first direction or the second direction in the circumferential direction of the balloon body, the outer diameter of the balloon can be suppressed without reducing the protrusions themselves. Therefore, both the strength of the balloon and the ease of insertion into the body cavity can be achieved.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Best Mode for Carrying Out the Invention

[0011] Hereinafter, the present invention will be specifically described based on embodiments. However, the present invention is not limited by the following embodiments, and it is of course possible to appropriately modify and implement within the range that can conform to the gist of the foregoing and following descriptions, and all of them are included in the technical scope of the present invention. In each drawing, for the sake of convenience, hatching, member codes, etc. may be omitted, but in such cases, reference shall be made to the specification and other drawings. Also, the dimensions of various members in the drawings may differ from the actual dimensions because priority is given to facilitating the understanding of the features of the present invention.

[0012] The balloon for a balloon catheter according to an embodiment of the present invention is a balloon for a balloon catheter having a straight tube portion, a proximal tapered portion located proximal to the straight tube portion, a proximal sleeve portion located proximal to the proximal tapered portion, a distal tapered portion located distal to the straight tube portion, and a distal sleeve portion located distal to the distal tapered portion, and includes a balloon body having an outer surface and an inner surface, and a protruding portion that protrudes radially outward from the outer surface of the balloon body and extends in the longitudinal axis direction of the balloon body. In a radial cross-section, the protruding portion provided in the straight tube portion has a proximal end connected to the outer surface of the balloon body, and a distal end located radially outward of the proximal end, which is the distal end of the protruding portion in the radial direction. and satisfies at least one of the following (1) and (2). (1) In a radial cross-section, the protruding portion provided in the proximal sleeve portion is inclined in the first direction or the second direction in the circumferential direction of the balloon body, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 45° or more. (2) In a radial cross-section, the protruding portion provided in the distal sleeve portion is inclined in the first direction or the second direction in the circumferential direction of the balloon body, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 45° or more.

[0013] As described above, the balloon for a balloon catheter according to an embodiment of the present invention has a protrusion, which enhances the strength of the balloon to prevent the balloon from stretching or breaking in an undesired direction. When the balloon is moved forward or backward, the protrusion provided on the distal sleeve portion and / or the proximal sleeve portion at the leading end causes the protrusion to fall in the first direction or the second direction in the circumferential direction of the balloon body. Thus, the fallen protrusion acts like a cushion, enabling smooth insertion through the body cavity and improving the trackability of the balloon catheter. Further, since the protrusion provided on the distal sleeve portion and / or the proximal sleeve portion falls in the first direction or the second direction in the circumferential direction of the balloon body, the outer diameter of the balloon can be suppressed without reducing the protrusion itself. Therefore, both the strength of the balloon and the ease of insertion into the body cavity can be achieved simultaneously.

[0014] With reference to FIGS. 1 to 10, the balloon for a balloon catheter according to an embodiment of the present invention will be described. FIG. 1 shows a side view of a balloon catheter according to an embodiment of the present invention. FIG. 2 shows a cross-sectional view taken along line II-II of FIG. 1, and represents a cross-sectional view of the straight tube portion of the balloon of the balloon catheter shown in FIG. 1 in an expanded state. FIG. 3 shows a cross-sectional view of the expanded portion shown in FIG. 2 in a contracted state. FIG. 4 shows a cross-sectional view taken along line IV-IV of FIG. 1, and represents a cross-sectional view of the distal tapered portion of the balloon of the balloon catheter shown in FIG. 1 in an expanded state. FIG. 5 shows a cross-sectional view of the distal tapered portion shown in FIG. 4 in a contracted state. FIG. 6 shows a cross-sectional view taken along line VI-VI of FIG. 1, and represents a cross-sectional view of the distal sleeve portion of the balloon of the balloon catheter shown in FIG. 1. FIG. 7 shows a modified example of FIG. 6. FIGS. 8 to 10 show cross-sectional views of balloons for balloon catheters according to different embodiments of the present invention. FIG. 8 shows a cross-sectional view of the distal sleeve portion. FIGS. 9 and 10 show cross-sectional views of the distal tapered portion in a contracted state. FIG. 9 shows a cross-sectional view of the more distal distal tapered portion, and FIG. 10 shows a cross-sectional view of the more proximal distal tapered portion. In this specification, the balloon for a balloon catheter may be simply referred to as a "balloon".

[0015] In the present invention, the proximal side refers to the direction toward the user's hand side with respect to the extending direction of the balloon catheter 1 or the longitudinal axis direction of the shaft 3, and the distal side refers to the opposite direction of the proximal side, that is, the direction toward the subject side to be treated. It is preferable that the longitudinal axis direction of the balloon catheter 1 is the same as the longitudinal axis direction x of the balloon body 20. Also, in this specification, even for members other than the long-shaped members, it will be described as having the same longitudinal axis direction x. The radial direction y of the balloon body 20 is a direction perpendicular to the longitudinal axis direction x and is a direction connecting the center of the balloon body 20 and a point on the outer edge of the balloon body 20 in the expanded state in a cross section perpendicular to the longitudinal axis direction x. The circumferential direction z of the balloon body 20 is a direction along the outer edge of the balloon body 20 in the expanded state in a cross section in the radial direction y.

[0016] As shown in FIG. 1, the balloon catheter 1 has a shaft 3 and a balloon 2 provided at the distal end of the shaft 3. The balloon catheter 1 is configured such that fluid is supplied into the balloon 2 through the shaft 3, and the expansion and contraction of the balloon 2 can be controlled using an inflator (balloon pressurizer). The fluid may be a pressurized fluid pressurized by a pump or the like.

[0017] The shaft 3 preferably has a fluid flow path inside and further has an insertion passage for a guide wire. In order for the shaft 3 to have a fluid flow path and a guide wire insertion passage inside, for example, the shaft 3 has an outer tube 31 and an inner tube 32, the inner tube 32 functions as an insertion passage for the guide wire, and the space between the inner tube 32 and the outer tube 31 functions as a fluid flow path. In the case where the shaft 3 has such a configuration of having the outer tube 31 and the inner tube 32, it is preferable that the inner tube 32 extends from the distal end of the outer tube 31 and penetrates distally of the balloon 2, the distal side of the balloon 2 is joined to the inner tube 32, and the proximal side of the balloon 2 is joined to the outer tube 31.

[0018] As shown in FIG. 1, the balloon 2 for a balloon catheter has a straight tube portion 23, a proximal tapered portion 22 located closer to the proximal side than the straight tube portion 23, a proximal sleeve portion 21 located closer to the proximal side than the proximal tapered portion 22, a distal tapered portion 24 located farther from the proximal side than the straight tube portion 23, and a distal sleeve portion 25 located farther from the proximal side than the distal tapered portion 24. It also has a balloon body 20 having an outer surface and an inner surface, and a protruding portion 60 that protrudes outward in the radial direction y from the outer surface of the balloon body 20 and extends in the longitudinal axis direction x of the balloon body 20. In the cross-section in the radial direction y, the protruding portion 60 provided on the straight tube portion 23 has a base end 61 connected to the outer surface of the balloon body 20, and a tip end 62 located outward in the radial direction y from the base end 61 and being the outer end of the protruding portion 60 in the radial direction y, and satisfies at least one of the following (1) and (2). and satisfies at least one of the following (1) and (2). (1) In the cross-section in the radial direction y, the protruding portion 60 provided on the proximal sleeve portion 21 is inclined in the first direction d1 or the second direction d2 in the circumferential direction z of the balloon body 20, and the straight line L p connecting the midpoint in the width direction of the base end 61 and the tip end 62 v and the perpendicular line L of the base end 61 form an angle θ of 45° or more. p and the perpendicular line L v of the base end 61 form an angle θ of 45° or more. Since the balloon 2 has the protrusion 60, the strength of the balloon 2 can be increased to prevent the balloon 2 from extending or breaking in an undesired direction. Further, when the balloon 2 is inserted into the body cavity and delivered to the lesion in the body cavity, the protrusion 60 provided on the distal sleeve portion 25 and / or the proximal sleeve portion 21 that becomes the leading end during the forward or backward movement of the balloon 2 falls in the first direction d1 or the second direction d2 in the circumferential direction z of the balloon body 20. Thus, the fallen protrusion 60 acts like a cushion, enabling smooth insertion through the body cavity and making the balloon 2 for a balloon catheter with improved trackability. Furthermore, since the protrusion 60 provided on the distal sleeve portion 25 and / or the proximal sleeve portion 21 falls in the first direction d1 or the second direction d2 in the circumferential direction z of the balloon body 20, the outer diameter of the balloon 2 can be suppressed without reducing the protrusion 60 itself. Therefore, both the strength of the balloon 2 and the ease of insertion into the body cavity can be achieved.

[0019] As shown in FIG. 1, the balloon 2 has a straight tube portion 23, a proximal tapered portion 22 located proximal to the straight tube portion 23, a proximal sleeve portion 21 located proximal to the proximal tapered portion 22, a distal tapered portion 24 located distal to the straight tube portion 23, and a distal sleeve portion 25 located distal to the distal tapered portion 24. At least a part of the proximal sleeve portion 21 and the distal sleeve portion 25 can be configured to be fixed to the shaft 3. In the case where the shaft 3 has an outer tube 31 and an inner tube 32, at least a part of the proximal sleeve portion 21 can be fixed to the outer tube 31, and at least a part of the distal sleeve portion 25 can be fixed to the inner tube 32.

[0020] The proximal tapered portion 22, the straight tube portion 23, and the distal tapered portion 24 are portions that are expanded by supplying fluid into the balloon 2 through the shaft 3. It is preferable that the proximal sleeve portion 21 and the distal sleeve portion 25 do not expand even when fluid is supplied into the balloon 2. Thereby, the fixation between the balloon 2 and the shaft 3 can be stabilized even in the expanded state of the balloon 2.

[0021] The straight tube portion 23 preferably has the same diameter in the longitudinal axis direction x, and the proximal tapered portion 22 and the distal tapered portion 24 are preferably formed so as to have a reduced diameter as they are separated from the straight tube portion 23. Since the proximal tapered portion 22 and the distal tapered portion 24 have a reduced diameter, when the balloon 2 is contracted, the outer diameters of the proximal end portion and the distal end portion of the balloon 2 can be reduced to reduce the step between the shaft 3 and the balloon 2, making it easier to insert the balloon 2 into the body cavity.

[0022] As shown in FIG. 2, the balloon 2 has a balloon body 20 having an outer surface and an inner surface, and a protruding portion 60 that protrudes outward in the radial direction y from the outer surface of the balloon body 20 and extends in the longitudinal axis direction x of the balloon body 20. When the balloon 2 is delivered to the lesion, as shown in FIG. 2, the balloon body 20 can be expanded, and treatment such as incising the stenosis of the lesion can be performed by the protruding portion 60.

[0023] The protruding portion 60 provided in the straight tube portion 23 has a proximal end 61 connected to the outer surface of the balloon body 20 and a distal end 62 located outward in the radial direction y from the proximal end 61. Regardless of the shape of the cross-section of the protruding portion 60 in the radial direction y, the outer end in the radial direction y can be uniquely determined, and the distal end 62 of the protruding portion 60 can be defined. It is preferable to fix the balloon 2 to the lesion at the distal end 62, make an incision in the lesion, and further penetrate the protruding portion 60 into the lesion up to the proximal end 61 side to incise the lesion and expand the stenosis. The distal end 62 of the protruding portion 60 may have a sharp shape with an acute angle or a shape having a curved surface or a flat surface, but from the above viewpoint, the distal end 62 preferably has a sharp shape.

[0024] The proximal end 61 has a predetermined width in the circumferential direction z of the balloon body 20. The width of the proximal end 61 in the circumferential direction z is preferably 1 / 100 or more of the circumferential length of the balloon body 20, more preferably 1 / 80 or more, still more preferably 1 / 70 or more. Also, it is preferably 1 / 4 or less, more preferably 1 / 8 or less, and still more preferably 1 / 10 or less.

[0025] As shown in FIG. 2, a plurality of protruding portions 60 may be provided in the circumferential direction z, or although not shown, one protruding portion 60 may be provided in the circumferential direction z. The number of the protruding portions 60 in the circumferential direction z when a plurality of protruding portions 60 are provided in the circumferential direction z is not particularly limited. For example, 2 or more is preferable, 3 or more is more preferable, and 4 or more may be sufficient. Also, 10 or less is preferable, 8 or less is preferable, and 6 or less may be sufficient. In this case, the protruding portions 60 are preferably arranged at intervals in the circumferential direction z, and more preferably arranged at equal intervals in the circumferential direction z. Thereby, it becomes easier to fix the balloon 2 and incise the stenosis.

[0026] The protrusion 60 may be provided continuously or intermittently from the proximal end to the distal end of the balloon body 20. Further, the protrusion 60 may be arranged parallel to the longitudinal axis direction x of the balloon body 20, or may be arranged in a spiral shape so as to go around the outer surface of the balloon body 20 in the circumferential direction z. If the protrusion 60 is arranged parallel to the longitudinal axis direction x, the stenosis can be incised straight by the protrusion 60. If the protrusion 60 is arranged in a spiral shape, the stenosis can be incised obliquely by the protrusion 60.

[0027] The shape of the cross section perpendicular to the longitudinal axis direction x of the protrusion 60 may be any shape, may be a substantially triangular shape as shown in FIG. 2, or may be a polygon, a fan shape, a wedge shape, a convex shape, a spindle shape, etc.

[0028] It is preferable that the protrusion 60 provided on the straight tube portion 23 does not fall in either the first direction d1 or the second direction d2 in the circumferential direction z. Thereby, the fixation of the balloon 2 to the lesion portion by the protrusion 60 and the incision of the stenosis can be performed efficiently. When the protrusion 60 does not fall in either the first direction d1 or the second direction d22 in the circumferential direction z, a straight line L connecting the midpoint in the width direction of the proximal end 61 and the distal end 62 p and the perpendicular line L of the proximal end 61 v coincide, that is, a straight line L connecting the midpoint in the width direction of the proximal end 61 and the distal end 62 p and the perpendicular line L of the proximal end 61 v The angle formed therewith is preferably 0°. It is also acceptable that the absolute value of the angle is 3° or less, 5° or less, 10° or less. At this time, the above straight line L p and the perpendicular line L of the proximal end 61 v The angle formed therewith is measured from the midpoint in the width direction of the proximal end 61 as the starting point, and the straight line L p is the angle formed in the direction in which the protrusion 60 falls with respect to the perpendicular line L of the proximal end 61 v Here, the perpendicular line L v is a perpendicular line to the line segment connecting one end and the other end in the circumferential direction z of the proximal end 61 in the cross section in the radial direction y.

[0029] The maximum value of the height of the protrusion 60 in the straight tube portion 23 is preferably at least 1 times the film thickness of the balloon body 20, more preferably at least 1.5 times, still more preferably at least 2 times, and is also allowed to be 50 times or less, 30 times or less, or 10 times or less. When the height of the protrusion 60 is within the above range, the incision of the stenosis by the protrusion 60 becomes easy, the elongation of the balloon 2 in the longitudinal axis direction x can be easily prevented, and the pushability of the balloon 2 can also be improved. The height of the protrusion 60 is obtained by subtracting the length from the center of the balloon body 20 to the point where the line segment connecting the center of the balloon body 20 and the tip 62 intersects the outer edge of the balloon body 20 in the cross section in the radial direction y. and the length up to the intersection point of the balloon body 20.

[0030] As shown in FIG. 3, in the contracted state of the balloon 2, it is preferable that the balloon body 20 in the straight tube portion 23 forms vanes 29 and the vanes 29 are folded. At this time, the protrusion 60 is formed in a portion other than the vanes 29, and it is preferable that the vanes 29 are folded so as to cover the protrusion 60. The balloon 2 is conveyed to the lesion part in the body cavity in the contracted state. Since the protrusion 60 is covered by the vanes 29, it is possible to prevent the protrusion 60 from unnecessarily damaging the body cavity wall or the protrusion 60 from being damaged during conveyance. Even in the contracted state, it is preferable that the protrusion 60 provided in the straight tube portion 23 does not fall in either the first direction d1 or the second direction d2 in the circumferential direction z. Thereby, it is possible to maintain a state where the protrusion 60 does not fall when the balloon 2 is expanded.

[0031] The number of the vanes 29 in the contracted state of the balloon 2 is not particularly limited. For example, 2 or more are preferable, 3 or more are more preferable, 4 or more may be sufficient, and 10 or less are preferable, 8 or less are more preferable, and 6 or less are still more preferable. If the number of the vanes 29 is within the above range, the balloon 2 can be easily contracted.

[0032] As shown in FIG. 4, the protruding portion 60 provided on the distal tapered portion 24 may not fall in either the first direction d1 or the second direction d2 in the circumferential direction z. Although not shown for the proximal tapered portion 22, similar to the distal tapered portion 24, the protruding portion 60 provided on the proximal tapered portion 22 may not fall in either the first direction d1 or the second direction d2 in the circumferential direction z. Since the protruding portion 60 of the tapered portion does not fall in the expanded state of the balloon 2, the balloon 2 can be fixed to the lesion or the stenosis can be incised by the protruding portion 60 disposed on the tapered portion. In the contracted state of the balloon 2 as shown in FIG. 5, since the tapered portion is easily folded so that the outer diameter is smaller than that of the straight tube portion 23, the balloon 2 can be delivered to the lesion without significantly impairing the insertability of the balloon 2 even if the protruding portion 60 does not fall.

[0033] The balloon 2 satisfies at least one of the following (1) and (2). (1) In the cross-section in the radial direction y, the protruding portion 60 provided on the proximal sleeve portion 21 falls in the first direction d1 or the second direction d2 in the circumferential direction z of the balloon body 20, and the straight line L connecting the midpoint in the width direction of the proximal end 61 and the distal end 62 p and the perpendicular line L of the proximal end 61 v form an angle θ of 45° or more. (2) In the cross-section in the radial direction y, the protruding portion 60 provided on the distal sleeve portion 25 falls in the first direction d1 or the second direction d2 in the circumferential direction z of the balloon body 20, and the straight line L connecting the midpoint in the width direction of the proximal end 61 and the distal end 62 p and the perpendicular line L of the proximal end 61 v form an angle θ of 45° or more.

[0034] Here, the perpendicular line L v is a perpendicular line to the line segment connecting one end and the other end in the circumferential direction z of the proximal end 61 in the cross-section in the radial direction y.

[0035] FIG. 6 shows a cross-sectional view of the distal sleeve portion 25. Since the proximal sleeve portion 21 can be described in the same manner, it will be described with reference to FIG. 6. As shown in FIG. 6, the protruding portion 60 provided on the proximal sleeve portion 21 and / or the distal sleeve portion 25 is inclined in the first direction d1 or the second direction d2 in the circumferential direction z, and a straight line L connecting the midpoint in the width direction of the proximal end 61 and the distal end 62 p and the perpendicular line L of the proximal end 61 v The angle θ formed therewith is 45° or more. With such a configuration, when the balloon 2 is conveyed in the body cavity to the lesion portion, the inclined protruding portion 60 acts like a cushion between the balloon body 20 and the body cavity wall, so that the balloon 2 can smoothly move in the body cavity and can be inserted, and the balloon 2 with improved trackability can be obtained. Further, since the protruding portion 60 is only inclined in the circumferential direction z and the protruding portion 60 itself is not reduced, the effect of preventing the balloon 2 from stretching and improving the pushability by the protruding portion 60 is maintained while suppressing the outer diameter of the balloon 2, and the insertion of the balloon 2 can be facilitated. The angle θ is preferably 50° or more, more preferably 60° or more, and even more preferably 65° or more. The upper limit of the angle θ is naturally limited because the proximal end 61 is connected to the outer surface of the balloon body 20 and the distal end 62 can only be inclined until it contacts the outer surface of the balloon body 20. For example, the angle θ may be 100° or less, 95° or less, or 90° or less. At this time, the angle θ formed by the straight line L p and the perpendicular line L of the proximal end 61 v is defined as the angle formed by the midpoint in the width direction of the proximal end 61 as the starting point and the straight line L p with respect to the perpendicular line L of the proximal end 61 v in the direction in which the protruding portion 60 is inclined.

[0036] Here, when the protruding portion 60 is inclined in the first direction d1 or the second direction d2 in the circumferential direction z, the outer end in the radial direction y of the protruding portion 60 in that state is different from the outer end when the protruding portion 60 is not inclined. However, in this specification, the distal end 62 when the protruding portion 60 is inclined refers to the same portion as the distal end 62 when the protruding portion 60 is not inclined.

[0037] In both the proximal sleeve portion 21 and the distal sleeve portion 25, it is preferable that the protruding portion 60 is tilted in the first direction d1 or the second direction d2 in the circumferential direction z. Thereby, when the balloon 2 is advanced and retracted in the body cavity, the protruding portions 60 provided on both the distal sleeve portion 25 and the proximal sleeve portion 21, which are at the leading end, act like cushions, and the balloon 2 can smoothly penetrate the body cavity in both the forward and backward directions, and the balloon 2 with improved trackability can be obtained.

[0038] Alternatively, only in the distal sleeve portion 25, the protruding portion 60 may be tilted in the first direction d1 or the second direction d2 in the circumferential direction z, and in the proximal sleeve portion 21, the protruding portion 60 may not be tilted. Thereby, the protruding portion 60 provided on the distal sleeve portion 25, which is at the leading end when the balloon 2 is advanced in the body cavity, acts like a cushion, and the balloon 2 can be easily advanced. At this time, since the proximal portion of the balloon 2 can be supported against the body cavity wall by the protruding portion 60 arranged in the proximal sleeve portion 21 during transportation, the trackability of the balloon 2 can be improved.

[0039] Or alternatively, only in the proximal sleeve portion 21, the protruding portion 60 may be tilted in the first direction d1 or the second direction d2 in the circumferential direction z, and in the distal sleeve portion 25, the protruding portion 60 may not be tilted. Thereby, it becomes possible to perform a treatment in which the balloon 2 gently advances while scraping the body cavity wall by the protruding portion 60 arranged in the distal sleeve portion 25, which is the leading end side of the balloon 2, and when the balloon 2 is retracted, it can be easily retracted by the cushioning action of the protruding portion 60 arranged and tilted in the proximal sleeve portion 21.

[0040] As shown in FIG. 7, when a plurality of protruding portions 60 are provided in the circumferential direction z, one protruding portion 60 may be tilted in the first direction d1 in the circumferential direction z, and the other protruding portions 60 may be tilted in the second direction d2 in the circumferential direction z.

[0041] As shown in FIG. 6, it is preferable that a space is formed between the tip 62 of the fallen protrusion 60 and the outer surface of the balloon body 20, and the distance h from the outer surface of the balloon body 20 to the tip 62, which can be an index representing the size of this space, is preferably a predetermined value or more. The distance h can be defined as the distance between the tangent line of the outer surface of the balloon body 20 perpendicular to the line segment connecting the center of the balloon body 20 and the tip 62, and a straight line parallel to the tangent line and passing through the tip 62. The distance h is preferably 1 / 5 or more of the film thickness of the balloon body 20, more preferably 1 / 4 or more, still more preferably 1 / 2 or more, and is also allowed to be 10 times or less, 5 times or less, or 3 times or less. If the distance h is within the above range, the size of the space formed between the tip 62 of the fallen protrusion 60 and the outer surface of the balloon body 20 can be made a predetermined value or more, and the tracking performance of the balloon 2 can be improved by the cushioning action of the fallen protrusion 60. The tip 62 of the end and the outer surface of the balloon body 20 can have a space of a predetermined size or more, and the tracking performance of the balloon 2 can be improved by the cushioning action of the fallen protrusion 60.

[0042] In any case, the protrusion 60 disposed in the sleeve portion may fall in all ranges in the longitudinal axis direction x, or may fall in a part of the longitudinal axis direction x. The range in which the protrusion 60 is fallen can be determined according to how much cushioning property is to be imparted.

[0043] The balloon 2 preferably satisfies at least one of the following (3) and (4). (3) In the cross-section in the radial direction y, the protrusion 60 of the proximal sleeve portion 21 falls in the first direction d1 or the second direction d2, and the straight line L connecting the midpoint in the width direction of the base end 61 and the tip 62 p and the perpendicular line L of the base end 61 v The angle formed is 45° or more, The proximal sleeve portion 21 has an inner protrusion 70 that protrudes inward in the radial direction y from the inner surface of the balloon body 20 and extends in the longitudinal axis direction x. (4) In the cross-section in the radial direction y, the protrusion 60 of the distal sleeve portion 25 falls in the first direction d1 or the second direction d2, and the straight line L connecting the midpoint in the width direction of the base end 61 and the tip 62 p and the perpendicular line L of the base end 61v The angle formed is 45° or more, The distal sleeve portion 25 has an inner protruding portion 70 that protrudes inward in the radial direction y from the inner surface of the balloon body 20 and extends in the longitudinal axis direction x.

[0044] As shown in FIG. 8, it is preferable that the proximal sleeve portion 21 and / or the distal sleeve portion 25 have an inner protruding portion 70 that protrudes inward in the radial direction y from the inner surface of the balloon 20 and extends in the longitudinal axis direction x at the portion where the protruding portion 60 is collapsed. Thereby, even at the portion where the protruding portion 60 is collapsed, the strength of the proximal end portion and / or the distal end portion of the balloon 2 can be improved by the inner protruding portion 70. The inner protruding portion 70 is preferably arranged at the same position as the protruding portion 60 in the circumferential direction z. Thereby, the strength of the proximal end portion and / or the distal end portion of the balloon 2 can be further improved.

[0045] The balloon 2 preferably satisfies at least one of the following (5) and (6). (5) In the cross-section in the radial direction y, the protruding portion 60 of the proximal sleeve portion 21 is collapsed in the first direction d1 or the second direction d2, and the straight line L connecting the midpoint in the width direction of the base end 61 and the tip end 62 p and the perpendicular line L of the base end 61 v The angle θ formed therewith is 45° or more, In the cross-section in the radial direction y, the protruding portion 60 of the proximal tapered portion 22 is collapsed in the first direction d1 or the second direction d2, and the straight line L connecting the midpoint in the width direction of the base end 61 and the tip end 62 p and the perpendicular line L of the base end 61 v The angle formed therewith is 30° or more. (6) In the cross-section in the radial direction y, the protruding portion 60 of the distal sleeve portion 25 is collapsed in the first direction d1 or the second direction d2, and the straight line L connecting the midpoint in the width direction of the base end 61 and the tip end 62 p and the perpendicular line L of the base end 61 v The angle θ formed therewith is 45° or more, In the cross-section in the radial direction y, the protruding portion 60 of the distal tapered portion 24 is collapsed in the first direction d1 or the second direction d2, and the straight line L connecting the midpoint in the width direction of the base end 61 and the tip end 62p and the perpendicular line L to the proximal end 61 v forms an angle of 30° or more.

[0046] As shown in FIGS. 9 and 10, in the tapered portion, the protruding portion 60 may also fall in the first direction d1 or the second direction d2. FIG. 9 shows a cross-sectional view of the distal tapered portion 24 on the more distal side in the contracted state, and FIG. 10 shows a cross-sectional view of the distal tapered portion 24 on the more proximal side in the contracted state. Thus, on the more distal side, that is, the end side of the balloon 2 far from the straight tube portion 23, in the portion where the length of the blade 29 in the contracted state is short, the protruding portion 60 falls deeply, and on the more proximal side, that is, the straight tube portion 23 side of the balloon 2, in the portion where the length of the blade 29 in the contracted state is long, a mode in which the fall of the protruding portion 60 is shallow is also preferable. Thereby, the closer to the straight tube portion 23, the shallower the fall of the protruding portion 60, and when delivered to the lesion, the protruding portion 60 disposed in the distal tapered portion 24 facilitates fixing the balloon 2 to the lesion or incising the stenosis. This explanation can be similarly made for the proximal tapered portion 22. That is, on the more proximal side of the proximal tapered portion 22, that is, the end of the balloon 2 far from the straight tube portion 23, in the portion where the length of the blade 29 in the contracted state is short, the protruding portion 60 falls deeply, and on the more distal side, that is, the straight tube portion 23 side of the balloon 2, in the portion where the length of the blade 29 in the contracted state is long, a mode in which the fall of the protruding portion 60 is shallow is also preferable. That the protruding portion 60 falls deeply means that the distance h is short, and that the protruding portion 60 falls shallowly means that the distance h is long. By determining how to determine the distance h, the magnitude of the cushioning property by falling the protruding portion 60 can be controlled.

[0047] Alternatively, the protruding portion 60 in the tapered portion may fall to the same extent in the longitudinal axis direction x. Further, the protruding portion 60 may have a portion that falls and a portion that does not fall in the longitudinal axis direction x.

[0048] Since the protrusion 60 in the tapered portion is fallen, the protrusion 60 in the tapered portion can also function as a cushion, and the trackability of the balloon 2 can be improved. Regarding the effect of whether the protrusion 60 disposed in either the proximal tapered portion 22 and / or the distal tapered portion 24 is fallen, reference can be made to the effect of whether the protrusion 60 disposed in either the proximal sleeve portion 21 and / or the distal sleeve portion 25 is fallen.

[0049] The angle θ at which the protrusion 60 in the tapered portion falls is preferably 30° or more, more preferably 45° or more, still more preferably 50° or more, and may be, for example, 95° or less, 90° or less, or 80° or less.

[0050] The balloon 2 preferably satisfies at least one of (7) and (8). (7) In the cross-section in the radial direction y, the protrusion 60 of the proximal sleeve portion 21 falls in the first direction d1 or the second direction d2, and the straight line L p connecting the midpoint in the width direction of the proximal end 61 and the distal end 62 v and the perpendicular line L of the proximal end 61 form an angle of 45° or more, p In the cross-section in the radial direction y, the protrusion 60 of the proximal tapered portion 22 falls in the first direction d1 or the second direction d2, and the straight line L v connecting the midpoint in the width direction of the proximal end 61 and the distal end 62 form an angle of 30° or more, (8) In the cross-section in the radial direction y, the protrusion 60 of the distal sleeve portion 25 falls in the first direction d1 or the second direction d2, and the straight line L p connecting the midpoint in the width direction of the proximal end 61 and the distal end 62 v and the perpendicular line L of the proximal end 61 In the cross-section in the radial direction y, the protruding portion 60 of the distal tapered portion 24 is tilted in the first direction d1 or the second direction d2, and a straight line L connecting the midpoint in the width direction of the proximal end 61 and the tip 62 p and the perpendicular line L of the proximal end 61 v form an angle of 30° or more, The distal sleeve portion 25 and the distal tapered portion 24 have an inner protruding portion 70 that protrudes inward in the radial direction y from the inner surface of the balloon body 20 and extends in the longitudinal axis direction x.

[0051] In the portion where the protruding portion 60 arranged in the tapered portion and the sleeve portion is tilted, it preferably has an inner protruding portion 70 that protrudes inward in the radial direction y from the inner surface of the balloon 20 and extends in the longitudinal axis direction x. Thereby, even in the portion where the protruding portion 60 is tilted, the strength of the proximal end portion and / or the distal end portion of the balloon 2 can be improved by the inner protruding portion 70. The inner protruding portion 70 is preferably arranged at the same position as the protruding portion 60 in the circumferential direction z. Thereby, the strength of the proximal end portion and / or the distal end portion of the balloon 2 can be further improved. Although the inner protruding portion arranged in the tapered portion is not shown, reference can be made to the inner protruding portion 70 in FIG. 8.

[0052] Examples of the material constituting the balloon body 20 include polyolefin resins such as polyethylene, polypropylene, and ethylene-propylene copolymer, polyester resins such as polyethylene terephthalate and polyester elastomer, polyurethane resins such as polyurethane and polyurethane elastomer, polyphenylene sulfide resins, polyamide resins such as polyamide and polyamide elastomer, fluorine resins, silicone resins, and natural rubbers such as latex rubber. These may be used alone or in combination of two or more. Among them, polyamide resins, polyester resins, and polyurethane resins are preferably used. In particular, it is preferable to use an elastomer resin from the viewpoint of thinning the balloon body 20 and flexibility. For example, among polyamide resins, nylon 12, nylon 11, etc. are suitable as the resin constituting the balloon body 20, and nylon 12 is more suitable because it can be formed relatively easily during blow molding. Also, from the viewpoint of thinning the balloon body 20 and flexibility, polyamide elastomers such as polyether ester amide elastomer and polyamide ether elastomer are preferably used. Among them, polyether ester amide elastomer is preferably used because of its high yield strength and good dimensional stability of the balloon body 20.

[0053] The protruding portion 60 and the inner protruding portion 70 are preferably made of the same material as the balloon body 20. If the protruding portion 60 and the inner protruding portion 70 are made of the same material as the balloon body 20, it is possible to prevent the protruding portion 60 and the inner protruding portion 70 from easily damaging the outer surface of the balloon body 20 while maintaining the flexibility of the balloon 2. The balloon body 20, the protruding portion 60, and the inner protruding portion 70 are preferably integrally formed. Thereby, it is possible to prevent the protruding portion 60 and the inner protruding portion 70 from falling off from the balloon body 20.

[0054] The balloon 2 can be manufactured by placing a tubular parison 200 made of resin, such as shown in FIG. 11, in a mold having grooves in its inner cavity and performing biaxial stretch blow molding. The protrusion 60 can be formed, for example, by inserting the parison 200 into the inner cavity of the mold, causing the thick-walled portion 220 of the parison to enter the grooves of the mold, and introducing a fluid into the inner cavity 210 of the parison 200 to expand the parison 200. When forming the inner protrusion 70, for example, the thick-walled portion 220 of the parison 200 is pressed against a portion of the mold without grooves, and a fluid is introduced into the inner cavity 210 of the parison 200 to expand the parison 200, thereby forming the inner protrusion 70. As the material constituting the parison 200, reference can be made to the description of the material constituting the balloon body 20 above.

[0055] Examples of the material constituting the shaft 3 include polyamide-based resins, polyester-based resins, polyurethane-based resins, polyolefin-based resins, fluorine-based resins, vinyl chloride-based resins, silicone-based resins, natural rubber, and the like. These may be used alone or in combination of two or more. Among them, the material constituting the shaft 3 is preferably at least one of a polyamide-based resin, a polyolefin-based resin, and a fluorine-based resin. Thereby, the slipperiness of the surface of the shaft 3 can be enhanced, and the insertability of the balloon catheter 1 in the body cavity can be improved.

[0056] Examples of the joining of the balloon 2 and the shaft 3 include adhesion with an adhesive, welding, and caulking by attaching a ring-shaped member to a portion where the end of the balloon 2 and the shaft 3 overlap. Among them, it is preferable that the balloon 2 and the shaft 3 are joined by welding. Since the balloon 2 and the shaft 3 are welded, the joining of the balloon 2 and the shaft 3 is less likely to be released even when the balloon 2 is repeatedly expanded and contracted, and the joining strength of the balloon 2 and the shaft 3 can be easily increased.

[0057] As shown in Fig. 1, a hub 4 may be provided on the proximal side of the shaft 3, and the hub 4 may be provided with a fluid injection portion 7 communicating with a flow path of the fluid supplied into the balloon 2. Further, the hub 4 preferably has a guide wire insertion portion 5 communicating with an insertion path of the guide wire. Since the balloon catheter 1 has the hub 4 including the fluid injection portion 7 and the guide wire insertion portion 5, operations such as supplying fluid into the balloon 2 to expand and contract the balloon 2, and delivering the balloon catheter 1 along the guide wire to the treatment site can be easily performed. Thus, not only in the so-called over-the-wire type balloon catheter in which the guide wire is inserted from the distal side to the proximal side of the shaft, but also the balloon 2 according to the embodiment of the present invention can be applied to a so-called rapid exchange type balloon catheter in which the guide wire is inserted up to the middle of the way from the distal side to the proximal side of the shaft.

[0058] The joining of the shaft 3 and the hub 4 includes, for example, adhesion with an adhesive, welding, and the like. Among these, it is preferable that the shaft 3 and the hub 4 are joined by adhesion. When the shaft 3 and the hub 4 are adhered, for example, when the shaft 3 is made of a highly flexible material and the hub 4 is made of a highly rigid material, and the materials constituting the shaft 3 and the hub 4 are different, the joining strength between the shaft 3 and the hub 4 can be increased to enhance the durability of the balloon catheter 1.

Explanation of Reference Numerals

[0059] 1: Balloon catheter 2: Balloon 3: Shaft 4: Hub 5: Guide wire insertion portion 7: Fluid injection portion 20: Balloon body 21: Proximal sleeve portion 22: Proximal tapered portion 23: Straight tube portion 24: Distal tapered portion 25: Distal sleeve portion 29: Blade 31: Outer tube 32: Inner tube 60: Protrusion 61: Base end 62: Tip 70: Inner protrusion 200: Parison 210: Inner cavity of parison 220: Wall thickness part of parison x: Longitudinal axis direction of balloon body y: Radial direction of balloon body z: Circumferential direction of balloon body d1: First direction d2: Second direction L v : Perpendicular line at the base end L p : Straight line connecting the midpoint in the width direction at the base end and the tip θ: The angle formed by L v and L p and h: From the outer surface of the balloon body in the space formed between the outer surface of the balloon body and the tip Distance to the tip

Claims

1. A balloon for a balloon catheter, comprising a straight tube portion, a proximal tapered portion located proximal to the straight tube portion, a proximal sleeve portion located proximal to the proximal tapered portion, a distal tapered portion located distal to the straight tube portion, and a distal sleeve portion located distal to the distal tapered portion, a balloon body having an outer surface and an inner surface, and a protruding portion protruding radially outward from the outer surface of the balloon body and extending in the longitudinal axis direction of the balloon body, in the radial cross-section, the protruding portion provided on the straight tube portion has a proximal end connected to the outer surface of the balloon body, and a distal end located radially outward of the proximal end and being the radially outer end of the protruding portion, in the radial cross-section, for the protruding portion provided on the straight tube portion, the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 10° or less, A balloon for a balloon catheter satisfying at least one of the following (1) and (2). (1) In the radial cross-section, the protruding portion of the proximal tapered portion is tilted in the first direction or the second direction in the circumferential direction of the balloon body, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 30° or more. (2) In the radial cross-section, the protruding portion of the distal tapered portion is tilted in the first direction or the second direction in the circumferential direction of the balloon body, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 30° or more.

2. The balloon for a balloon catheter according to Claim 1, satisfying at least one of the following (3) and (4). (3) In the radial cross-section, the protruding portion of the proximal tapered portion is tilted in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 30° or more, and the proximal tapered portion has an inner protruding portion protruding radially inward from the inner surface of the balloon body and extending in the longitudinal axis direction. (4) In the radial cross-section, the protruding portion of the distal tapered portion is tilted in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 30° or more, The distal tapered portion has an inner protruding portion that protrudes radially inward of the inner surface of the balloon body and extends in the longitudinal axis direction.

3. The balloon for a balloon catheter according to claim 1 or 2, satisfying at least one of the following (5) and (6). (5) In the cross-section in the radial direction, the protruding portion of the proximal tapered portion falls in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 30° or more. The protruding portion falls in the first direction or the second direction throughout the longitudinal axis direction of the proximal tapered portion. (6) In the cross-section in the radial direction, the protruding portion of the distal tapered portion falls in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 30° or more. The protruding portion falls in the first direction or the second direction throughout the longitudinal axis direction of the distal tapered portion.

4. The balloon for a balloon catheter according to claim 1 or 2, satisfying at least one of the following (7) and (8). (7) In the cross-section in the radial direction, the protruding portion of the proximal tapered portion falls in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 30° or more. The protruding portion falls in the first direction or the second direction in at least a part of the longitudinal axis direction of the proximal tapered portion. (8) In the cross-section in the radial direction, the protruding portion of the distal tapered portion falls in the first direction or the second direction, and the angle formed by the straight line connecting the midpoint in the width direction of the proximal end and the distal end and the perpendicular line to the proximal end is 30° or more. The protruding portion falls in the first direction or the second direction in at least a part of the longitudinal axis direction of the distal tapered portion.

5. A catheter comprising the balloon for a balloon catheter according to claim 1 or 2.

Images