Balloon catheter

Abstract

This balloon catheter comprises: a balloon 13 that can expand and contract; and a linear protrusion 20 that protrudes from the surface of the balloon 13 and extends in the axial direction of the balloon 13 along the surface thereof. A plurality of the protrusions 20 are arranged at intervals in the circumferential direction of the balloon 13. The balloon 13 is formed in a contracted state and has vanes 22 extending to the outside in the radial direction of the balloon 13. The vanes 22 extend in the axial direction of the balloon 13, and each vane is arranged so that the entirety thereof is positioned between adjacent protrusions 20 in the circumferential direction of the balloon 13 when viewed in a cross-section orthogonal to the axial direction.

Description

Cross-reference to Related Applications

[0001] This application is based on Japanese Application No. 2023-082515 filed on May 18, 2023, the contents of which are incorporated herein by reference.

Technical Field

[0002] The present disclosure relates to a balloon catheter.

Background Art

[0003] A balloon catheter has a balloon that can be inflated and deflated on its tip side. The balloon catheter introduces the balloon in a contracted state into a location narrowed or blocked by a lesion or the like that has occurred in a blood vessel, and then expands the balloon to expand the location.

[0004] Some balloon catheters have a linear element provided on the outer surface of the balloon that extends in the axial direction. The element is provided in a state of protruding from the outer surface of the balloon. In a balloon catheter with an element, the element is pressed against the lesion by inflating the balloon to treat the lesion. For example, by inflating the balloon, the element can be made to bite into the lesion to make a cut in the lesion, and based on this cut, it becomes possible to make it easier to expand the lesion.

[0005] In a balloon catheter, when the balloon is in a contracted state, blade portions that protrude radially outward are formed on the balloon. For example, Patent Document 1 discloses a configuration in which blade portions are formed on a balloon in a contracted state in a balloon catheter with an element. In the balloon catheter of this Patent Document 1, the blade portions are arranged so as to cover the entire element.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] International Publication No. 2020 / 012851 [Overview of the project] [Problems that the invention aims to solve]

[0007] Incidentally, in the balloon catheter described in Patent Document 1, the fin portion is positioned to cover the entire element when the balloon is deflated. As a result, the outer diameter of the balloon when it is deflated becomes larger than the top of the protrusion by the thickness of the fin portion. Therefore, this may lead to a decrease in the ease of insertion when inserting the balloon into the body.

[0008] This disclosure has been made in view of the above circumstances, and its primary purpose is to provide a balloon catheter that can suppress the decrease in insertability when inserting the balloon into the body. [Means for solving the problem]

[0009] To solve the above problems, the balloon catheter of the first disclosure comprises an inflatable and deflated balloon, and linear projections protruding from the surface of the balloon and extending along the surface in the axial direction of the balloon, wherein a plurality of projections are arranged at intervals in the circumferential direction of the balloon, and the balloon has fin portions formed in its deflated state and extending radially outward from the balloon, the fin portions extending in the axial direction and arranged such that when viewed in a cross section perpendicular to the axial direction, the entire fin portion is located between adjacent projections in the circumferential direction.

[0010] According to the first disclosure, the balloon has fins that are formed when it is deflated, and these fins extend in the axial direction of the balloon. The fins are positioned such that, when viewed in a cross-section perpendicular to the axial direction, they are entirely located between adjacent protrusions. In this case, the fins are positioned without covering the tops of the protrusions. Therefore, it is possible to avoid the outer diameter of the balloon increasing due to the fins covering the tops of the protrusions. This makes it possible to suppress a decrease in the ease of insertion when inserting the balloon into the body.

[0011] The balloon catheter of the second disclosure, in the first disclosure, has a wing portion that is bent so as to be convex in the circumferential direction, and the wing portion is elastically deformable in the radial direction.

[0012] According to the second disclosure, the fin portion has a bent portion that is bent so as to be convex in the circumferential direction of the balloon, and this bent portion allows the fin portion to be elastically deformed in the radial direction of the balloon. In this configuration, when the fin portion comes into contact with the wall of a tube such as a blood vessel when the balloon is inserted into the tube, the fin portion elastically deforms radially inward of the balloon. Therefore, the decrease in the ease of inserting the balloon can be further suppressed.

[0013] The balloon catheter of the third disclosure, in the second disclosure, has a portion of the wing that is located radially outward from the tops of the adjacent projections.

[0014] According to the third disclosure, the fin portion has a part that is located radially outward of the balloon than the tops of adjacent protrusions. In this case, when introducing the balloon into a tube inside the body, the fin portion is more likely to contact the tube wall before the tops of the protrusions. Therefore, it is possible to prevent the tops of the protrusions from getting caught on the tube wall. In addition, since the fin portion elastically deforms radially inward of the balloon when it contacts the tube wall, it is possible to prevent a decrease in the balloon's insertability even with the above configuration.

[0015] The balloon catheter of the fourth disclosure, in any of the first to third disclosures, is bent such that the wing portion is curved such that the extending tip portion in the extending direction is covered from the radially outward by the portion that is more proximal to the tip portion in the extending direction.

[0016] According to the fourth disclosure, the tip of the fin portion is covered from the radially outer side of the balloon by the portion of the fin portion closer to the base end than the tip. This prevents the tip of the fin portion from getting caught on the tube wall when inserting the balloon into the tube.

[0017] The balloon catheter of the fifth disclosure comprises an inner tube inserted inside the balloon in any of the first to third disclosures, the balloon having a tube-facing portion formed in the deflated state and facing the outer circumferential surface of the inner tube, and when the adjacent protrusions are designated as a first protrusion and a second protrusion, the wing portion has a first portion extending radially outward from the tube-facing portion along the side surface of the first protrusion, a second portion extending circumferentially toward the second protrusion from the radially outward end of the first portion, and a third portion extending radially inward from the end of the second portion toward the second protrusion along the side surface of the second protrusion.

[0018] According to the fifth disclosure, the balloon has a tube-facing portion that is formed in its deflated state and faces the outer circumferential surface of the inner tube. The fin portion has a first portion that extends radially outward from the tube-facing portion along the side surface of the first projection, a second portion that extends circumferentially from the radially outward end of the first portion toward the second projection, and a third portion that extends radially inward from the end of the second portion toward the second projection along the side surface of the second projection. In this case, the amount by which the tops of adjacent projections (first projection and second projection) protrude radially outward from the balloon can be reduced compared to the fin portion. This makes it possible to prevent the tops of each projection from catching on the tube wall when inserting the balloon into the tube.

[0019] In the balloon catheter of the sixth disclosure, in any of the first to third disclosures, when the balloon is in the contracted state, the protrusion is disposed inclined toward the side of the blade portion.

[0020] According to the sixth disclosure, when the balloon is in the contracted state, the protrusion is disposed inclined toward the side of the blade portion, so that the amount of protrusion of the top of the protrusion protruding radially outside the balloon more than the blade portion can be suppressed. Thereby, when inserting the balloon into the tube, it is possible to prevent the top of the protrusion from being caught by the tube wall.

Brief Description of the Drawings

[0021] The above objects, other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings. [Figure 1] Schematic overall side view showing the configuration of the balloon catheter. [Figure 2] (a) is a side view showing the configuration of the balloon and its surroundings in the inflated state, and (b) is a cross-sectional view taken along the line A-A of (a). [Figure 3] It is a side view showing the configuration of the balloon and its surroundings in the inflated state, showing the balloon and the outer tube in a longitudinal section state. [Figure 4] Side view showing the configuration of the balloon and its surroundings in the contracted state. [Figure 5] Cross-sectional view taken along the line B-B of FIG. 4. [Figure 6] Cross-sectional view showing another form of the blade portion. [Figure 7] Cross-sectional view showing the state where the protrusion is tilted toward the blade portion side. [Figure 8] Diagram showing a configuration in which a notch is provided in the protrusion.

Mode for Carrying Out the Invention

[0022] Hereinafter, an embodiment embodying the present disclosure will be described with reference to the drawings. FIG. 1 is a schematic overall side view showing the configuration of the balloon catheter.

[0023] As shown in Figure 1, the balloon catheter 10 comprises a catheter body 11, a hub 12 attached to the proximal end of the catheter body 11, and a balloon 13 attached to the distal end of the catheter body 11.

[0024] The catheter body 11 comprises an outer tube 15 and an inner tube 16 inserted inside the outer tube 15. The outer tube 15 is formed in a tubular shape from a resin material and has a lumen 15a (see Figure 3) that extends throughout its entire axial direction. The proximal end of the outer tube 15 is joined to the hub 12, and the tip of the outer tube 15 is joined to the balloon 13. The lumen 15a of the outer tube 15 is connected to both the inside of the hub 12 and the inside of the balloon 13. The lumen 15a of the outer tube 15 serves as a fluid lumen through which compressed fluid flows when the balloon 13 is inflated or deflated.

[0025] The outer tube 15 may be formed by joining together a plurality of tubes aligned in the axial direction. In this case, the tubes on the base end may be made of a metal material, and the tubes on the tip end may be made of a resin material.

[0026] The inner tube 16 is formed in a tubular shape from a resin material and has a lumen 16a (see Figure 3) that extends along its entire axial direction. The proximal end of the inner tube 16 is joined to the outer tube 15 at an intermediate position along its axial direction. A portion of the tip of the inner tube 16 extends further forward than the outer tube 15, and this extended portion is inserted into the balloon 13. The area near the tip of the inner tube 16 is joined to the tip of the balloon 13.

[0027] The lumen 16a of the inner tube 16 is a guidewire lumen through which the guidewire G is inserted. The proximal opening 18 of the lumen 16a is located midway along the axial direction of the balloon catheter 10. Therefore, this balloon catheter 10 is considered an RX-type catheter. Alternatively, the proximal opening 18 of the lumen 16a may be located at the proximal end of the balloon catheter 10. In that case, the balloon catheter 10 would be considered an over-the-wire type catheter.

[0028] Next, the structure of the balloon 13 and its surroundings will be explained based on Figures 2 and 3. Figure 2 shows (a) a side view of the balloon 13 and its surroundings in the inflated state, and (b) a cross-sectional view of (a) along line AA. Figure 3 is a side view of the balloon 13 and its surroundings in the inflated state, showing the balloon 13 and the outer tube 15 in a longitudinal cross-sectional view.

[0029] The balloon 13 is formed from a thermoplastic resin material, for example, from a polyamide elastomer. As shown in Figures 2(a) and 3, the balloon 13 is formed in a cylindrical (tubular) shape with a circular cross-section overall. Specifically, the balloon 13 has a base leg portion 13a, a base tapered portion 13b, a straight tube portion 13c, a tip tapered portion 13d, and a tip leg portion 13e, and these portions 13a to 13e are arranged in the order described above from the base to the tip.

[0030] The proximal leg portion 13a is joined to the tip of the outer tube 15. The proximal tapered portion 13b is tapered, expanding in diameter from the tip of the proximal leg portion 13a towards the tip. The straight tube portion 13c extends from the tip of the proximal tapered portion 13b towards the tip with a constant diameter, forming a circular tube (cylindrical) shape. The straight tube portion 13c is the part of the balloon 13 that has the largest diameter when it is inflated. The tip tapered portion 13d is tapered, contracting in diameter from the tip of the straight tube portion 13c towards the tip. The tip leg portion 13e is joined to the tip of the inner tube 16.

[0031] When compressed fluid is supplied to the inside of the balloon 13 through the lumen 15a of the outer tube 15, the balloon 13 expands. On the other hand, when negative pressure is applied to the lumen 15a of the outer tube 15 and compressed fluid is discharged from inside the balloon 13, the balloon 13 deflates (see Figures 4 and 5).

[0032] Furthermore, a pair of contrast rings 19 are attached to the inside of the balloon 13 in the inner tube 16. The contrast rings 19 are intended to improve the visibility of the balloon 13 under X-ray projection and to facilitate the positioning of the balloon 13 to the target treatment site.

[0033] In this balloon catheter 10, a linear projection 20 is provided on the surface of the balloon 13. The projection 20 is intended to make an incision in the lesion when the lesion is expanded by inflating the balloon 13. In this balloon catheter 10, the projection 20 makes an incision in the lesion, which facilitates the expansion of the lesion. Therefore, this balloon catheter 10 is a balloon catheter with a scoring function.

[0034] The protrusions 20 are provided so as to protrude from the surface of the balloon 13. The protrusions 20 extend linearly along the surface of the balloon 13 in the axial direction of the balloon 13. Multiple protrusions 20 are arranged at predetermined intervals (more specifically, at equal intervals) in the circumferential direction of the balloon 13, and in this embodiment, three protrusions 20 are provided. Each protrusion 20 is provided on the straight tube section 13c of the balloon 13, and more specifically, it is provided over the entire axial area of ​​the straight tube section 13c. Furthermore, each protrusion 20 is integrally formed with the balloon 13, and the protrusion height from the surface of the balloon 13 is the same for all of them.

[0035] The protruding portion 20 may be provided on the base-side tapered portion 13b or the tip-side tapered portion 13d of the balloon 13, instead of or in addition to the straight-tube portion 13c. Furthermore, if the protruding portion 20 is provided on the tapered portions 13b and 13d in addition to the straight-tube portion 13c, it is conceivable that the protruding height of the protruding portion 20 on the tapered portions 13b and 13d be the same as the protruding height of the protruding portion 20 on the straight-tube portion 13c. However, the protruding height of the protruding portion 20 on the tapered portions 13b and 13d may be higher or lower than the protruding height of the protruding portion 20 on the straight-tube portion 13c.

[0036] Each projection 20 has a cross-sectional shape (more specifically, a cross-section perpendicular to the longitudinal direction of the projection 20) that protrudes radially outward from the balloon 13, and more specifically, it is triangular in shape. In the projection 20, the end on the tip side of the projection is a apex 20a. The projection 20 has two adjacent sides 20b connected by the apex 20a.

[0037] Next, the structure of the balloon 13 in its deflated state will be explained based on Figures 4 and 5. Figure 4 is a side view showing the structure of the balloon 13 and its surroundings in its deflated state. Figure 5 is a cross-sectional view of Figure 4 along line BB.

[0038] As shown in Figures 4 and 5, the balloon 13 comprises a tube-facing portion 21 and a wing portion 22 that are formed in its deflated state. The tube-facing portion 21 is the portion that faces the outer circumferential surface of the inner tube 16, which is inserted inside the balloon 13. The tube-facing portion 21 extends along the outer circumferential surface of the inner tube 16 in the circumferential direction of the inner tube 16 (in other words, the circumferential direction of the balloon 13).

[0039] The fin portions 22 extend outward from the tube-facing portion 21 in the radial direction of the balloon 13 (hereinafter also referred to as the balloon radial direction). Multiple fin portions 22 are provided at predetermined intervals (specifically, at equal intervals) in the circumferential direction of the balloon 13, and in this embodiment, three fin portions 22 are provided. Therefore, the number of fin portions 22 is the same as the number of protruding portions 20. Each fin portion 22 extends axially across the tapered portions 13b, 13d and the straight tube portion 13c of the balloon 13. Furthermore, each fin portion 22 is formed to have the same shape and size.

[0040] The wing portion 22 is formed by folding a part of the balloon 13. The wing portion 22 has a fold 24 extending in the axial direction of the balloon 13 at the tip portion 23 in the extending direction that extends from the tube-facing portion 21. The wing portion 22 is folded along the fold 24.

[0041] The tube opposing sections 21, like the fin sections 22, are provided in multiple locations around the balloon 13, specifically three in number. Therefore, the number of tube opposing sections 21 is the same as the number of fin sections 22. Each tube opposing section 21 is provided for each adjacent fin section 22. Each tube opposing section 21 extends across adjacent fin sections 22, connecting those adjacent fin sections 22.

[0042] Herein, the balloon catheter 10 has a distinctive feature in the configuration of its wing portion 22. Therefore, its distinctive configuration will be described below.

[0043] As shown in Figure 5, each wing portion 22 is positioned between adjacent protrusions 20 in the circumferential direction of the balloon 13 (hereinafter also referred to as the balloon circumferential direction). Specifically, each wing portion 22 is positioned such that, when viewed in a cross-section (i.e., a transverse plane) perpendicular to the axial direction of the balloon 13, the entire wing portion 22 is located between adjacent protrusions 20. In this case, each wing portion 22 is positioned so as not to cover the top portion 20a of the protrusion 20 from the outside in the radial direction of the balloon. Furthermore, because each wing portion 22 is positioned as described above, each wing portion 22 and each protrusion 20 are arranged alternately in the circumferential direction of the balloon 13.

[0044] Each wing portion 22 is positioned to straddle adjacent protrusions 20 in the circumferential direction of the balloon, with the wing portion 22 in between. Hereinafter, adjacent protrusions 20 will be referred to as one protrusion 20 and the other protrusion 20, respectively. Each wing portion 22 has a first portion 22a extending outward in the radial direction of the balloon from the tube-facing portion 21 along the side surface 20b of one protrusion 20 (corresponding to the first protrusion), a second portion 22b extending from the outer end of the first portion 22a in the radial direction of the balloon toward the other protrusion 20 (corresponding to the second protrusion) in the circumferential direction of the balloon, and a third portion 22c extending inward in the radial direction of the balloon from the end of the second portion 22b toward the other protrusion 20 along the side surface 20b of the said protrusion 20. The first portion 22a abuts against the side surface 20b of one protrusion 20, and the third portion 22c abuts against the side surface 20b of the other protrusion 20. Furthermore, the end of the third portion 22c opposite to the second portion 22b is the tip portion 23 of the wing portion 22.

[0045] The second part 22b is located at approximately the same position as the top 20a of each projection 20 in the radial direction of the balloon. In a cross-section (i.e., transverse plane) perpendicular to the axial direction of the balloon 13, if we consider a virtual circle E (see the dashed line in Figure 5) centered on the axis J (central axis) of the balloon 13 and passing through the top 20a of each projection 20, then the second part 22b extends in an arc shape along this virtual circle E. More specifically, a portion of the second part 22b protrudes outward from the virtual circle E in the radial direction of the balloon, forming an overhang 26. This overhang 26 is the portion of the second part 22b that is located outward from the top 20a of each projection 20 in the radial direction of the balloon. The amount of the protruding portion 26 (in other words, the length in the radial direction of the balloon) is smaller than the thickness of the fin portion 22, and in this embodiment, the amount of the protruding portion is approximately the same as the thickness of the balloon 13 (i.e., half the thickness of the fin portion 22).

[0046] In the wing portion 22, bent portions 27 and 28 are provided at both ends of the second portion 22b in the circumferential direction of the balloon. Of the bent portions 27 and 28, bent portion 27 is provided at the boundary between the second portion 22b and the first portion 22a, and bent portion 28 is provided at the boundary between the second portion 22b and the third portion 22c. Each bent portion 27 and 28 is bent so as to be convex toward opposite sides in the circumferential direction of the balloon, or more specifically, curved so as to be convex toward opposite sides. These bent portions 27 and 28 allow the wing portion 22 to be elastically deformable in the radial direction of the balloon. Furthermore, because the wing portion 22 is provided with bent portions 28, the tip portion 23 of the wing portion 22 is covered from the outside in the radial direction of the balloon by the second portion 22b. In this case, the second portion 22b corresponds to "the portion of the wing portion 22 that is closer to the base end than the tip portion 23 in the extension direction of the wing portion 22."

[0047] Because the blade portion 22 is provided with bent portions 27 and 28, the blade portion 22 is arranged in an annular shape. In this case, a predetermined space portion 25 is formed inside the blade portion 22. This space portion 25 is the space enclosed by the first portion 22a, the second portion 22b, and the third portion 22c of the blade portion 22.

[0048] Next, we will explain how to use the balloon catheter 10. Here, we will describe the procedure for dilating a lesion that has occurred in a blood vessel using the balloon catheter 10.

[0049] First, a guiding catheter is inserted through a sheath introducer that has been inserted into the blood vessel, and the tip of the guiding catheter is introduced to the coronary artery ostium. Next, a guidewire G is inserted through the guiding catheter, and the inserted guidewire G is introduced from the coronary artery ostium through the lesion to the peripheral site.

[0050] Next, the balloon catheter 10 is introduced into the guiding catheter along the guidewire G. After introduction, the balloon 13 is introduced (positioned) toward the lesion site while applying pushing and pulling operations. During this introduction, the balloon 13 is kept in a deflated state. When the balloon 13 is deflated, as described above, each wing portion 22 is formed on the balloon 13. These wing portions 22 are positioned so that, when viewed in cross-section, they are all located between adjacent protrusions 20 (see Figure 5). In this case, each wing portion 22 is positioned without covering the top 20a of the protrusion 20. Therefore, it is possible to avoid the outer diameter of the balloon 13 increasing due to the wing portions 22 covering the top 20a of the protrusion 20. This helps to suppress a decrease in the insertability of the balloon 13 within the blood vessel.

[0051] Once the balloon 13 reaches the lesion, it is inflated. This causes the protrusion 20 to press against the lesion, creating a crack in the lesion. This crack then allows the lesion to be destroyed or otherwise expanded outwards.

[0052] After the expansion of the lesion by balloon 13 is complete, balloon 13 is deflated. Then, in this deflated state, the balloon catheter 10 is withdrawn from the body. This completes the series of procedures.

[0053] As mentioned above, the balloon catheter 10 is primarily used to treat blood vessels such as the coronary arteries, femoral arteries, and pulmonary arteries, but it can also be applied to other "tubes" and "body cavities" within the body, such as the ureters and digestive tract.

[0054] As described in detail above, the configuration of this embodiment provides the following excellent effects.

[0055] The wing portion 22 has bent portions 27 and 28 that are bent so as to be convex in the circumferential direction of the balloon 13, and these bent portions 27 and 28 allow for elastic deformation in the radial direction of the balloon 13. In this configuration, when the wing portion 22 comes into contact with the blood vessel wall when the balloon 13 is inserted into a blood vessel, the wing portion 22 (specifically the second portion 22b) is pressed against the blood vessel wall and elastically deforms radially inward of the balloon 13. Therefore, the decrease in the insertability of the balloon 13 can be further suppressed.

[0056] The wing portion 22 has a portion (specifically, an overhang 26) that is located radially outward from the tops 20a of the adjacent protrusions 20 in the circumferential direction of the balloon, flanking the wing portion 22. In this case, when inserting the balloon 13 into a blood vessel, the wing portion 22 is more likely to contact the blood vessel wall before the tops 20a of the protrusions 20. Therefore, it is possible to prevent the tops 20a of the protrusions 20 from getting caught on the blood vessel wall. In addition, since the wing portion 22 elastically deforms radially inward from the balloon 13 when it comes into contact with the blood vessel wall, it is possible to prevent a decrease in the insertability of the balloon 13 even with the above configuration.

[0057] The wing portion 22 is bent so that its tip portion 23 is covered from the radially outer side of the balloon 13 by the portion closer to the proximal end (specifically, the second portion 22b). This prevents the tip portion 23 of the wing portion 22 from catching on the blood vessel wall when inserting the balloon 13 into the blood vessel.

[0058] The balloon 13 is formed in its deflated state and has a tube-facing portion 21 that faces the outer circumferential surface of the inner tube 16. When adjacent protrusions 20 on either side of the wing portion 22 are referred to as one protrusion 20 and the other protrusion 20, the wing portion 22 has a first portion 22a extending outward in the balloon radial direction along the side surface 20b of one protrusion 20 from the tube-facing portion 21, a second portion 22b extending from the outer end of the first portion 22a in the balloon radial direction toward the other protrusion 20 in the balloon circumferential direction, and a third portion 22c extending inward in the balloon radial direction along the side surface 20b of the protrusion 20 from the end of the second portion 22b toward the other protrusion 20. In this case, the amount of protrusion of the tops of adjacent protrusions 20 that protrude outward in the balloon radial direction than the wing portion 22 can be reduced. This prevents the tops 20a of each protrusion 20 from getting caught on the blood vessel wall when inserting the balloon 13 into the blood vessel.

[0059] This disclosure is not limited to the embodiments described above, and may be implemented, for example, as follows.

[0060] (1) In the above embodiment, the wing portion 22 had a portion located outside the balloon radial direction of each of the tops 20a of the adjacent protrusions 20 in the balloon circumferential direction, sandwiching the wing portion 22 (specifically, an overhang portion 26). However, the wing portion 22 may be configured not to have an overhang portion 26. For example, the outer end of the wing portion 22 may be in the same position as the tops 20a of the adjacent protrusions 20 in the balloon radial direction. In other words, the wing portion 22 may be arranged so as to be in contact with the virtual circle E.

[0061] (2) Figures 6(a) to 6(c) show alternative configurations of the wing portion. The wing portion 31 shown in Figure 6(a) extends in a wavy shape along the circumferential direction of the balloon 13. In this case, the wing portion 31 is provided with a plurality of bent portions 33 that are bent so as to be convex radially outward of the balloon 13. With this configuration, when the balloon 13 is inserted into a blood vessel, each bent portion 33 of the wing portion 31 comes into contact with the blood vessel wall. This reduces the contact area between the wing portion 31 and the blood vessel wall. Therefore, when inserting the balloon 13 into a narrowed area in a blood vessel, the passability of the balloon 13 can be improved.

[0062] (3) The wing portion 41 shown in Figure 6(b) extends in a wavy shape along the radial direction of the balloon 13. In this case, the wing portion 41 is provided with a bent portion 42 that is bent so as to be convex on one side in the circumferential direction of the balloon 13, and a bent portion 43 that is bent so as to be convex on the other side in the circumferential direction of the balloon 13. These bent portions 42 and 43 allow the wing portion 41 to be elastically deformable in the radial direction of the balloon 13. Therefore, when the wing portion 41 hits the blood vessel wall when inserting the balloon 13 into a blood vessel, the wing portion 41 will elastically deform inward in the radial direction of the balloon 13. As a result, the decrease in the ease of inserting the balloon 13 into the blood vessel can be further suppressed.

[0063] (4) The wing portion 51 shown in Figure 6(c) is formed by bending it into a spiral shape when viewed in a cross-section (i.e., transverse plane) perpendicular to the axial direction of the balloon 13. In this case, the tip portion 53 of the wing portion 51 is located in the center of the spiral. This prevents the tip portion 53 of the wing portion 51 from getting caught on the blood vessel wall when inserting the balloon 13 into the blood vessel.

[0064] Furthermore, because the wing portion 51 is spiral-shaped, it includes a bent portion 55 that is bent so as to be convex in the circumferential direction of the balloon 13. This bent portion 55 allows the wing portion 51 to be elastically deformable in the radial direction of the balloon 13. Therefore, when the wing portion 51 comes into contact with the blood vessel wall, the wing portion 51 will elastically deform inward in the radial direction. This further suppresses the decrease in the insertability of the balloon 13 when it is inserted into a blood vessel.

[0065] Furthermore, the spiral shape of the wing portion 51 reduces the contact area between the wing portion 51 and the blood vessel wall. This reduces the sliding resistance between the wing portion 51 and the blood vessel wall when inserting the balloon 13 into a narrowed area in the blood vessel. As a result, the passage of the balloon 13 through the narrowed area can be improved.

[0066] (5) In the above embodiment, the second portion 22b of the wing portion 22 was located at approximately the same position as the top portion 20a of the projection portion 20 in the radial direction of the balloon. However, the second portion 22b of the wing portion 22 may be located further inward in the radial direction of the balloon than the top portion 20a of the projection portion 20. In this case, however, the top portion 20a of the projection portion 20 will be located further outward in the radial direction of the balloon than the wing portion 22. In such a case, as shown in Figure 7, the projection portion 20 may be positioned to tilt toward the wing portion 22 when the balloon 13 is in a deflated state. In the example in Figure 7, the projection portion 20 is tilted toward the wing portion 22 and overlapped with the wing portion 22. In this case, the amount of protrusion of the top portion 20a of the projection portion 20 that protrudes radially outward from the wing portion 22 of the balloon 13 can be suppressed. Therefore, when inserting the balloon 13 into a blood vessel, it is possible to suppress the top portion 20a of the projection portion 20 from getting caught on the blood vessel wall.

[0067] (6) As shown in Figure 8, notches 58 may be provided in each protruding portion 20 of the balloon 13. The notches 58 are formed in the middle of the longitudinal direction of the protruding portion 20, more specifically in the center of the longitudinal direction. In this case, the protruding portion 20 can be made easier to bend starting from the notches 58. Therefore, when inserting the balloon 13 into a curved blood vessel in the body, it is possible to make the balloon 13 follow the curve of the blood vessel.

[0068] In the conventional configuration where the top 20a of the protrusion 20 is covered by the wing portion 22 when the balloon 13 is deflated, there is a risk that the bending of the protrusion 20, starting from the notch 58, will be hindered by the wing portion 22. Therefore, when inserting the balloon 13 into a curved vessel, it may be difficult to make the balloon 13 follow the curve of the vessel. In contrast, in the configuration of the present disclosure, where the wing portion 22 is positioned between adjacent protrusions 20, the bending of the protrusion 20 is not hindered by the wing portion 22, making it easier to make the balloon 13 follow the curve of the vessel.

[0069] (7) In the above embodiment, the protrusion 20 was used to make an incision in the lesion, but the protrusion 20 may be used for other purposes. For example, by inflating the balloon 13 inside the blood vessel, the protrusion 20 may be made to bite into the blood vessel wall, thereby being used as an anti-slip device to prevent the balloon 13 from slipping.

[0070] This disclosure is described in accordance with embodiments, but it is understood that this disclosure is not limited to such embodiments or structures. This disclosure also includes various modifications and variations within the scope of equivalents. In addition, various combinations and forms, as well as other combinations and forms that include only one, more, or fewer of those elements, fall within the scope and idea of ​​this disclosure. [Explanation of Symbols]

[0071] 10...Balloon catheter, 13...Balloon, 16...Inner tube, 20...Protruding part, 20a...Top, 21...Opposite part of tube, 22...Wing part, 27...Bend part, 28...Bend part.

Claims

1. An inflatable and deflated balloon, The balloon comprises a linear projection that protrudes from the surface of the balloon and extends along the surface in the axial direction of the balloon, The aforementioned protrusions are arranged in a plurality at intervals in the circumferential direction of the balloon catheter, The balloon has a fin portion that is formed in its contracted state and extends radially outward from the balloon. The wing portion extends in the axial direction and is arranged such that, when viewed in a cross-section perpendicular to the axial direction, the entire portion is positioned between adjacent protrusions in the circumferential direction. A balloon catheter in which the wing portion is bent such that the tip portion in the extending direction is covered from the outside in the radial direction by a portion closer to the base end than the tip portion in the extending direction.

2. An inflatable and deflated balloon, The balloon comprises a linear projection that protrudes from the surface of the balloon and extends along the surface in the axial direction of the balloon, The aforementioned protrusions are arranged in a plurality at intervals in the circumferential direction of the balloon catheter, The balloon has a fin portion that is formed in its contracted state and extends radially outward from the balloon. The wing portion extends in the axial direction and is arranged such that, when viewed in a cross-section perpendicular to the axial direction, the entire portion is positioned between adjacent protrusions in the circumferential direction. The balloon is equipped with an inner tube inserted inside it, The balloon is formed in the contracted state and has a tube-facing portion that faces the outer circumferential surface of the inner tube. When the adjacent protrusions are designated as the first protrusion and the second protrusion, The aforementioned wing portion is, A first portion extending radially outward from the tube-facing portion along the side surface of the first protrusion, A second portion extending from the radially outer end of the first portion toward the second protruding portion in the circumferential direction, A balloon catheter having a third portion extending radially inward from the end of the second portion on the side of the second projection along the side of the second projection.

3. An inflatable and deflated balloon, The balloon comprises a linear projection that protrudes from the surface of the balloon and extends along the surface in the axial direction of the balloon, The aforementioned protrusions are arranged in a plurality at intervals in the circumferential direction of the balloon catheter, The balloon has a fin portion that is formed in its contracted state and extends radially outward from the balloon. The wing portion extends in the axial direction and is arranged such that, when viewed in a cross-section perpendicular to the axial direction, the entire portion is positioned between adjacent protrusions in the circumferential direction. The aforementioned protrusion is positioned at an angle toward the wing portion when the balloon is in the deflated state, in a balloon catheter.

4. The balloon catheter according to any one of claims 1 to 3, wherein the wing portion has a bent portion that is bent so as to be convex in the circumferential direction, and the bent portion is elastically deformable in the radial direction.

5. The balloon catheter according to claim 4, wherein the wing portion has a portion located radially outward from the tops of the adjacent protrusions.

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