JP2021097853A - Balloon catheter - Google Patents

Abstract

To provide a balloon catheter in which a narrow section is easily expanded.SOLUTION: A balloon catheter according to the present invention comprises: a shaft which extends in the far-near direction; and a balloon which is provided on the distal side of the shaft. The proximal end of the balloon is fastened to the shaft with a proximal side fastening section. The distal end of the balloon is fastened to the shaft with a distal side fastening section. The balloon comprises: a fixation section in which the balloon is directly or indirectly fixed to the shaft in a middle section on the distal side with respect to the distal end of the proximal side fastening section and on the proximal side with respect to the proximal end of the distal side fastening section; and a non-fixation section in which the balloon is not fixed to the shaft. The non-fixation section includes a reinforcement section. The fixation section and the reinforcement section are apart from each other by 1/4 or greater of the circumferential length in the circumferential direction of the balloon.SELECTED DRAWING: Figure 1

Description

The present invention relates to a balloon catheter.

It has been known that various diseases occur due to stenosis of blood vessels in the body. For example, stenosis of the coronary arteries that supply blood to the heart may lead to serious diseases such as angina pectoris and myocardial infarction. As one of the methods for treating such a narrowed portion of a blood vessel, a procedure for dilating the narrowed portion using a balloon catheter has been performed, and various balloon catheters have been known so far.

For example, Patent Document 1 describes an inner tube that is inserted into the lumen of an outer shaft and the inside of a balloon to form a guide wire lumen, and the radius of the inner tube that is fixed to or integrally formed with the inner tube on the outer peripheral surface of the inner tube. A balloon catheter is disclosed that comprises an anti-slip element that projects outward in the direction and presses the inner surface of the balloon when the balloon is expanded.

Further, in Patent Document 2, with respect to a balloon arranged so as to extend in the axial direction while contacting the outer periphery of the guide wire insertion tube extending from the tip of the outer shaft, and a position on the outer periphery in which the balloon is in contact. A balloon that is fixed to the outer periphery of the guide wire insertion tube or integrally formed with the guide wire insertion tube at a position opposite to the circumferential direction, and has an anti-slip element that projects radially outward of the guide wire insertion tube. The catheter is disclosed.

Japanese Unexamined Patent Publication No. 2016-096869 Japanese Unexamined Patent Publication No. 2016-220861

In a balloon catheter as disclosed in Patent Documents 1 and 2, when the balloon is inflated, one side of the balloon that is in direct or indirect contact with the tube provided with the anti-slip element is difficult to inflate, while the balloon catheter is directly or The other side of the balloon, which was not indirect contact, had a structure that easily expanded. With such a structure, the balloon may be curved when inflated, and the tube may also be curved, which may make it difficult to expand the narrowed portion.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a balloon catheter that easily dilates a stenotic portion.

The balloon catheter according to the present invention, which has been able to solve the above problems, has the following configuration.
[1] A balloon catheter including a shaft extending in the perspective direction and a balloon provided on the distal side of the shaft.
The proximal end of the balloon is anchored to the shaft by a proximal anchoring portion.
The distal end of the balloon is fixed to the shaft by the distal sticking portion.
The balloon is on the distal side of the distal end of the proximal sticking portion, in the middle of the proximal side of the proximal end of the distal sticking portion, and the balloon is directly on the shaft. Alternatively, it has a fixed portion that is indirectly fixed and a non-fixed portion in which the balloon is not fixed to the shaft.
The non-fixed portion has a reinforcing portion and
A balloon catheter characterized in that the fixing portion and the reinforcing portion are separated from each other by 1/4 or more of the peripheral length in the circumferential direction of the balloon.

As described above, the balloon has a fixed portion fixed to the shaft and a non-fixed portion not fixed to the shaft, and the non-fixed portion is separated from the fixed portion in the circumferential direction of the balloon by 1/4 or more of the peripheral length. By providing the reinforcing portion at the position, the bending of the shaft is suppressed, so that the narrowed portion can be easily expanded.

Further, the balloon catheter according to the present invention preferably includes the following configurations [2] to [16].
[2] The balloon catheter according to [1], wherein the shaft is located outside the balloon.
[3] The balloon catheter according to [2], wherein the shaft is provided with a protruding portion protruding toward the side opposite to the balloon in the middle portion.
[4] The balloon catheter according to [1], wherein the shaft is located inside the balloon.
[5] The balloon catheter according to [4], wherein the shaft includes a protruding portion that projects toward the fixed portion side.
[6] The balloon catheter according to [4] or [5], wherein the central axis of the shaft is located closer to the fixed portion side than the central axis of the balloon.
[7] The balloon catheter according to any one of [1] to [6], wherein the reinforcing portion is formed by a thick portion of the balloon.
[8] The balloon catheter according to any one of [1] to [7], wherein the reinforcing portion includes a reinforcing member.
[9] The balloon catheter according to any one of [1] to [8], wherein the maximum thickness of the reinforcing portion in the radial cross section of the balloon is equal to or larger than the maximum thickness of the shaft.
[10] The balloon catheter according to any one of [1] to [8], wherein the maximum thickness of the reinforcing portion in the radial cross section of the balloon is smaller than the maximum outer diameter of the shaft.
[11] The balloon catheter according to any one of [1] to [10], wherein the balloon includes a straight tube portion extending in the axial direction of the shaft, and the fixing portion is located in the straight tube portion.
[12] The balloon has a proximal taper portion that expands in diameter toward the distal side, a straight tube portion, and a distal taper portion that contracts in diameter toward the distal side, and the reinforcing portion. Is a balloon catheter according to any one of [1] to [11], which is located at least in the proximal taper portion, the straight tube portion, and the distal taper portion.
[13] The balloon catheter according to any one of [1] to [12], wherein the reinforcing portion has a long shape.
[14] The balloon catheter according to any one of [1] to [13], wherein the reinforcing portion has a hole extending in the perspective direction.
[15] The reinforcing portion according to [14], wherein the reinforcing portion is distal to the proximal end of the reinforcing portion and has an opening communicating with the hole on the proximal side of the distal end of the reinforcing portion. Balloon catheter.
[16] The balloon catheter according to [14] or [15], wherein a long body is slidably arranged in the hole.

According to the present invention, it is possible to provide a balloon catheter that can easily dilate a stenotic portion by the above configuration.

FIG. 1 is a side view of a balloon catheter according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a cross section of the region R in FIG. 1 in the axial direction. FIG. 3 is a cross-sectional view showing the AA cross section of the balloon catheter of FIG. FIG. 4 is a side view of a conventional balloon catheter. FIG. 5 is a cross-sectional view showing another example of the AA cross section of the balloon catheter of FIG. FIG. 6 is a cross-sectional view showing another example of the AA cross section of the balloon catheter of FIG. FIG. 7 is a cross-sectional view showing another example of the AA cross section of the balloon catheter of FIG. FIG. 8 is a cross-sectional view showing another example of the AA cross section of the balloon catheter of FIG. FIG. 9 is a cross-sectional view showing another example of the AA cross section of the balloon catheter of FIG. FIG. 10 is a cross-sectional view showing another example of the axial cross section of the region R of FIG. FIG. 11 is a side view of the balloon catheter according to another embodiment of the present invention. FIG. 12 is a cross-sectional view showing a BB cross section of the balloon catheter of FIG. FIG. 13 is a perspective view of a long body.

Hereinafter, the present invention will be described in more detail based on the following embodiments, but the present invention is not limited by the following embodiments as well as the present invention, and is appropriately modified to the extent that it can be adapted to the purpose of the above and the following. Of course, it is also possible to carry out the above, and all of them are included in the technical scope of the present invention. In each drawing, the member code and the like may be omitted for convenience, but in such a case, the specification and other drawings shall be referred to. In addition, the dimensions of various members in the drawings may differ from the actual dimensions because priority is given to contributing to the understanding of the features of the present invention.

The balloon catheter of the present invention is a balloon catheter including a shaft extending in the perspective direction and a balloon provided on the distal side of the shaft, and the proximal end of the balloon is a proximal side fixing portion. The distal end of the balloon is anchored to the shaft by the distal anchor, and the balloon is distal and farther than the distal end of the proximal anchor. A fixed portion in which the balloon is directly or indirectly fixed to the shaft and a non-fixed portion in which the balloon is not fixed to the shaft are provided in the middle portion on the proximal side of the proximal end of the fixed portion on the position side. The non-fixed portion has a reinforcing portion, and the fixed portion and the reinforcing portion are separated from each other by 1/4 or more of the circumferential length in the circumferential direction of the balloon.

As described above, in a balloon catheter having a fixed portion in which the balloon is directly or indirectly fixed to the shaft, a position where the non-fixed portion of the balloon is separated from the fixed portion in the circumferential direction of the balloon by 1/4 or more of the peripheral length. By providing the reinforcing portion in the balloon, the curvature of the balloon is suppressed, so that the narrowed portion can be easily expanded.

Hereinafter, the balloon catheter according to the embodiment of the present invention will be described with reference to FIGS. 1 to 13. FIG. 1 is a side view of a balloon catheter according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a cross section of the region R in FIG. 1 in the axial direction. FIG. 3 is a cross-sectional view showing the AA cross section of the balloon catheter of FIG. FIG. 4 is a side view of a conventional balloon catheter. 5-9 are cross-sectional views showing another example of the AA cross section of the balloon catheter of FIG. FIG. 10 is a cross-sectional view showing another example of the axial cross section of the region R of FIG. FIG. 11 is a side view of the balloon catheter according to another embodiment of the present invention. FIG. 12 is a cross-sectional view showing a BB cross section of the balloon catheter of FIG. FIG. 13 is a perspective view of a long body.

As shown in FIGS. 1 and 2, the balloon catheter 1 includes a shaft 10 extending in the perspective direction X and a balloon 20 provided on the distal side of the shaft 10. Further, the proximal end 20A of the balloon 20 is fixed to the shaft 10 by the proximal side fixing portion 20a, and the distal end 20B of the balloon 20 is fixed to the shaft 10 by the distal side fixing part 20b.

The proximal side fixing portion 20a and the distal side fixing portion 20b are portions where the balloon 20 and the shaft 10 are firmly bonded by welding or the like. In FIGS. 1 and 2, the shaft 10 has an inner tube 11 and an outer tube 12, and the distal side fixing portion 20b of the balloon 20 is fixed to the outer surface of the inner tube 11, and the balloon 20 The proximal side fixing portion 20a is fixed to the outer surface of the inner tube 11 and the outer surface of the outer tube 12. The proximal side fixing portion 20a and the distal side fixing portion 20b may each exist over a part of the circumferential direction of the shaft 10, or may exist over the entire circumferential direction. The inner pipe 11 can be used as an insertion passage for a guide wire or the like. Further, the space between the inner tube 11 and the outer tube 12 can be a flow path of the fluid, and the balloon 20 can be inflated by injecting the fluid into the pressurized lumen 20I of the balloon 20 through the flow path. it can. Examples of the fluid include liquids, and examples of the liquids include physiological saline and contrast media.

As shown in FIGS. 1 to 3, the balloon 20 is distal to the distal end 20X of the proximal anchoring portion 20a and proximal to the proximal end 20Y of the distal anchoring portion 20b. The intermediate portion 20c has a fixing portion 20F in which the balloon 20 is directly fixed to the shaft 10. Specifically, in the fixing portion 20F existing in the intermediate portion 20c, the balloon 20 is fixed by directly contacting the outer surface of the shaft 10 (inner pipe 11) along the axial direction of the shaft 10 (inner pipe 11). Has been done. The fixed portion 20F is difficult to stretch due to the rigidity of the shaft 10 (inner tube 11) even when the pressurized lumen 20I is pressurized. Further, the fixed portion 20F is a portion in which the balloon 20 is indirectly in contact with the shaft 10 (inner pipe 11) via an inclusion such as a protruding portion 13 as shown in FIGS. 11 and 12 described later. May be good. Further, in the fixing portion 20F, the balloon 20 may be fixed by being adhered to the shaft 10 (inner tube 11) or the like.

As shown in FIGS. 1 to 3, the balloon 20 has a non-fixed portion 20N in which the balloon 20 is not fixed to the shaft 10 in the middle portion 20c, and the non-fixed portion 20N has a reinforcing portion 22. Further, the fixed portion 20F and the reinforcing portion 22 are separated from each other by 1/4 or more of the circumferential length in the circumferential direction of the balloon 20. For example, in the conventional balloon catheter 100 shown in FIG. 4, the fixed portion 20F and the non-fixed portion 20N on the opposite side of the fixed portion 20F (hereinafter, may be referred to as the opposite non-fixed portion 20N) are fixed. There was a difference in rigidity due to the presence or absence. Further, the conventional balloon catheter 100 is provided with an anti-slip element (protruding portion 13) that projects toward the side opposite to the balloon 20, so that the difference in rigidity is large and the balloon 20 is curved when expanded. It was easy. On the other hand, in the balloon catheter 1 according to the embodiment of the present invention, as shown in FIG. 3, the reinforcing portion 22 is provided at a position separated from the fixing portion 20F in the circumferential direction of the balloon 20 by 1/4 or more of the peripheral length. Since the difference in rigidity between the fixed portion 20F of the balloon 20 and the non-fixed portion 20N on the opposite side can be reduced, the curvature at the time of expansion of the balloon and the curvature of the shaft 10 can also be reduced, and the lesion portion can be easily expanded. can do. Further, this makes it possible to easily expand the shaft 10 by cracking the highly stenotic lesion or the calcified lesion when the shaft 10 has the protruding portion 13. Further, this also makes it easier for the protruding portion 13 to exert a non-slip function or the like. In FIG. 3, the alternate long and short dash line is a line passing through the central axis 20C of the balloon 20, and the portion below the alternate long and short dash line is a portion separated from the fixed portion 20F in the circumferential direction of the balloon 20 by 1/4 or more of the peripheral length. Corresponds to and corresponds to the opposite side non-fixed portion 20N. The reinforcing portion 22 is preferably separated from the fixed portion 20F in the circumferential direction of the balloon 20 by 5/16 or more of the peripheral length, and more preferably 6/16 or more of the peripheral length.

Although not shown, the fixing portion 20F may be provided at two or more locations. In that case, the adjacent fixing portion 20F and the reinforcing portion 22 may be separated from each other by 1/4 or more of the peripheral length in the circumferential direction of the balloon 20.

As shown in FIGS. 5 and 6, the reinforcing portions 22 may be provided at two or more locations in the circumferential direction of the balloon 20. On the other hand, although the upper limit is not particularly limited, the reinforcing portions 22 may be provided at 10 or less locations in the circumferential direction of the balloon 20 or may be provided at 5 or less locations. When three or more reinforcing portions 22 are provided in the circumferential direction, it is preferable that the reinforcing portions 22 are provided at regular intervals in the circumferential direction of the balloon 20 as shown in FIG.

As shown in FIGS. 1 and 2, the reinforcing portion 22 is preferably elongated. This makes it easier to prevent the balloon 20 from bending. When the reinforcing portion 22 has a long shape, it is preferable that the reinforcing portion 22 extends in the axial direction of the shaft 10. When the reinforcing portion 22 has a long shape, it is not limited to the linear shape as shown in FIGS. 1 and 2, but may have a wavy line shape, a zigzag shape, or the like. These are not limited to one type, and two or more types may be provided in combination. Further, the reinforcing portion 22 is not limited to a long shape but may be a net shape or the like.

Examples of the shape of the reinforcing portion 22 in the circumferential cross section of the balloon 20 include a polygonal shape such as a triangular shape, a rectangular shape, and a trapezoidal shape, a hemispherical shape, and a spherical shape. Further, as will be described in detail later, as shown in FIGS. 9 and 10, the reinforcing portion 22 may have a hole 22H extending in the perspective direction X. The cross-sectional shape of the hole 22H in the circumferential cross section of the balloon 20 is not particularly limited, and examples thereof include polygons such as triangles, rectangles, and trapezoids, hemispheres, and spheres.

The reinforcing portion 22 may be provided with a reinforcing member as shown in FIGS. 3, 5 and 6, or is formed by a part of the balloon 20 as shown in FIGS. 7, 8 and 9. It may have been done.

Examples of the reinforcing member include metal wire and resin wire. Examples of the material constituting the metal wire include stainless steel, titanium, nickel-titanium alloy, cobalt-chromium alloy, tungsten alloy and the like. The metal wire may be a single wire or a stranded wire. Examples of the material constituting the resin wire include polyarylate fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, PBO fiber, carbon fiber and the like. These fibrous materials may be monofilaments or multifilaments. In addition, as the material constituting the resin wire, the resin constituting the balloon 20 described later may be used. The reinforcing member may be adhered to the balloon 20 with an adhesive or the like, or may be fixed to the balloon 20 by welding or the like.

As a mode in which the reinforcing portion 22 is formed by a part of the balloon 20, as shown in FIG. 7, a mode in which the reinforcing portion 22 is formed by a protruding thick portion 20P of the balloon 20, as shown in FIG. A mode in which the reinforcing portion 22 is formed by a hill-shaped thick portion 20T of the balloon 20, a mode in which the reinforcing portion 22 is formed by a rail-shaped thick portion 20R of the balloon 20, and the like, as shown in FIG. Can be mentioned. For the shape of the thick portion, the description of the shape of the reinforcing portion 22 can be referred to. Although not shown, the reinforcing portion 22 may be formed by a thick portion of the balloon 20 and a reinforcing member.

Examples of the resin constituting the balloon 20 include at least one selected from the group consisting of polyamide-based resin, polyester-based resin, polyurethane-based resin, polyolefin-based resin, vinyl chloride-based resin, silicone-based resin, and natural rubber. .. Of these, at least one selected from the group consisting of polyamide-based resins, polyester-based resins, and polyurethane-based resins is preferable. Moreover, you may use an elastomer resin as these resins.

The balloon 20 can be manufactured by molding a resin. For example, the balloon 20 can be manufactured by arranging a resin tube extruded by extrusion molding in a mold and performing biaxial stretching blow molding. The balloon 20 can also be manufactured by a known molding method such as dip molding, injection molding, or compression molding.

The dimensions of the balloon 20 are preferably 5 mm to 300 mm in the axial direction and 1 mm to 12 mm in the outer diameter when the treatment site is a blood vessel, and the shaft when the treatment site is the gastrointestinal tract such as the duodenal papilla. It is preferable that the length in the direction is 10 mm to 100 mm and the outer diameter is 3 mm to 30 mm.

As shown in FIG. 1, the balloon 20 preferably includes a straight pipe portion 21c extending in the axial direction of the shaft 10, and the fixing portion 20F is preferably located at the straight pipe portion 21c. When the shaft 10 includes the straight tube portion 21c, the lesion portion can be easily expanded. Further, since the fixed portion 20F is located at the straight tube portion 21c, the diastolic pressure of the straight tube portion 21c can be easily applied to the lesion portion. Further, the balloon 20 has a proximal side tapered portion 21a whose diameter increases toward the distal side, a straight tube portion 21c, and a distal side tapered portion 21b whose diameter decreases toward the distal side, and is a fixed portion. It is also preferable that the 20F is located at least at the proximal side tapered portion 21a, the straight pipe portion 21c, and the distal side tapered portion 21b.

The balloon 20 has a proximal taper portion 21a that expands in diameter toward the distal side, a straight tube portion 21c, and a distal taper portion 21b that contracts in diameter toward the distal side, and has a reinforcing portion 22. Is preferably located at least at the proximal side tapered portion 21a, the straight pipe portion 21c, and the distal side tapered portion 21b. When the balloon 20 has the proximal side tapered portion 21a, the straight pipe portion 21c, and the distal side tapered portion 21b in this way, it is easy to prevent the balloon 20 from bending by providing the reinforcing portion 22 in each portion. can do. Further, the reinforcing portion 22 may be provided in at least one portion selected from the group consisting of the proximal side tapered portion 21a, the straight pipe portion 21c, and the distal side tapered portion 21b. Further, the reinforcing portion 22 is also provided in a place other than the proximal side tapered portion 21a, the straight pipe portion 21c, and the distal side tapered portion 21b, for example, the proximal side fixing portion 20a, the distal side fixing portion 20b, and the like. You may. For example, the reinforcing portion 22 may be provided on the proximal side fixing portion 20a, the proximal side taper portion 21a, the straight pipe portion 21c, the distal side taper portion 21b, and the distal side fixing portion 20b. Further, the reinforcing portions 22 of each portion may be integrated and continuously provided, or may be provided separately. Further, the balloon 20 may have other shapes, and may include, for example, a spherical portion, a long spherical portion, or the like.

The balloon 20 may include a linear thin-walled portion along the axial direction of the shaft 10. As a result, the balloon 20 before expansion can be easily folded.

As shown in FIGS. 1 to 3 and the like, it is preferable that the shaft 10 is provided with a protruding portion 13 projecting toward the side opposite to the balloon 20 in the intermediate portion 20c. The protrusion 13 can crack and facilitate dilation of highly stenotic or calcified lesions. Further, the protruding portion 13 may exert a non-slip function or the like. Even when the shaft 10 does not have the protruding portion 13, the reinforcing portion 22 can crack the shaft 10 or exert a non-slip function as described later.

The shaft 10 (inner tube 11) is preferably located outside the balloon 20. As a result, the protruding portion 13 or the like can be provided on the portion of the shaft 10 (inner tube 11) opposite to the balloon 20.

On the other hand, the shaft 10 (inner tube 11) may be located inside the balloon 20 as shown in FIGS. 11 and 12. Further, the shaft 10 may include a protruding portion 13 projecting toward the fixed portion 20F side. Also in such an aspect, the calcified lesion can be easily cracked and expanded by the fixed portion 20F which is convex by the protruding portion 13. Further, it is possible to prevent the balloon 20 from being displaced when expanded. Further, according to such an aspect, it is possible to prevent the protruding portion 13 from falling apart from the shaft 10. The balloon catheter 1 of FIG. 11 has the same configuration as the balloon catheter 1 of FIG. 1 except that a part of the inner tube 11 is located inside the balloon 20.

As shown in FIG. 12, the central axis 10C of the shaft 10 is preferably located closer to the fixed portion 20F than the central axis 20C of the balloon 20. As a result, even when the protrusion 13 is small, it is possible to easily crack and expand a highly stenotic lesion or a calcified lesion. In addition, this makes it easier for the protruding portion 13 to exert a non-slip function or the like.

The shape of the protruding portion 13 in the circumferential cross section of the balloon 20 is not particularly limited, and examples thereof include a polygonal shape such as a triangular shape, a rectangular shape, and a trapezoidal shape, a hemispherical shape, and a spherical shape. In the case of a triangular shape, the apex angle (θ) is preferably 30 ° or more and 100 ° or less, and more preferably 40 ° or more and 60 ° or less.

The protruding portion 13 may be provided with a protruding member, or may be formed by a part of the shaft 10. Examples of the material constituting the projecting member include metal and resin. Examples of the metal include stainless steel, titanium, nickel-titanium alloy, cobalt-chromium alloy, tungsten alloy and the like. Further, for the resin, the description of the resin constituting the balloon 20 can be referred to. The projecting member may be adhered to the shaft 10 with an adhesive or the like, or may be fixed to the shaft 10 by welding or the like. Further, as an embodiment in which the protrusion 13 is formed by a part of the shaft 10, for example, the protrusion 13 is formed by the protrusion of the shaft 10, and the protrusion 13 is formed by the thick portion of the shaft 10. And so on.

As a combination of the protruding portion 13 and the reinforcing portion 22, the protruding portion 13 is formed by a part of the shaft 10, and the reinforcing portion 22 is formed by a part of the balloon 20; the protruding portion 13 protrudes. A combination in which a member is provided and the reinforcing portion 22 is formed by a part of the balloon 20; a combination in which the protruding portion 13 is formed by a part of the shaft 10 and the reinforcing portion 22 is provided with the reinforcing member. ; Or a combination in which the protruding portion 13 includes a protruding member and the reinforcing portion 22 includes a reinforcing member; As the curvature of the balloon 20 is reduced, the protrusion 13 can be easily cracked and expanded for highly stenotic lesions and calcified lesions. In addition, this makes it easier for the protruding portion 13 to exert a non-slip function or the like. On the other hand, not only the curvature of the balloon 20 may be prevented, but also the curvature of the balloon 20 at the time of expansion may be left to some extent and the curvature may be used. For example, by providing a certain degree of rigidity difference between the protruding portion 13 and the shaft 10 and the reinforcing portion 22, the reinforcing portion 22 of the balloon 20 is located outside the curve and tends to be convex toward the outside, so that the reinforcing portion 22 tends to be convex. This makes it possible to crack and easily expand highly stenotic lesions and calcified lesions. In addition, this makes it easier for the protruding portion 13 to exert a non-slip function or the like.

The number of protrusions 13 is not limited to one, and two or more protrusions 13 may be provided on the shaft 10. In this case, it is preferable that the plurality of projecting portions 13 are arranged linearly along the axial direction of the shaft 10. The flexural modulus that can be measured based on JIS K 7171 (2016) of the material constituting the protrusion 13 is preferably 50 MPa or more. This makes it easier to crack stenotic lesions and calcified lesions. Therefore, the flexural modulus is more preferably 100 MPa or more, and even more preferably 150 MPa or more. On the other hand, if the flexural modulus is 10,000 MPa or less, the difference in rigidity between the protruding portion 13 and the reinforcing portion 22 can be reduced to facilitate bending. Therefore, the flexural modulus is more preferably 5,000 MPa or less, and further preferably 2,000 MPa or less. The difference between the flexural modulus of the protruding portion 13 and the shaft 10 and the flexural modulus of the reinforcing portion 22 is preferably 10,000 MPa or less. This makes it easier to prevent bending due to the difference in rigidity. Therefore, the difference in flexural modulus is more preferably 1,500 MPa or less, and even more preferably 100 MPa or less. Further, when the curvature of the balloon 20 at the time of expansion is left to some extent and the curvature is used, the difference in flexural modulus may be 50 MPa or more, or 150 MPa or more.

As shown in FIGS. 3 and 12, in the radial cross section of the balloon 20, the maximum thickness 22T of the reinforcing portion 22 is preferably 10T or more of the maximum thickness of the shaft 10. As a result, it is possible to easily suppress the bending of the shaft 10 due to the difference in rigidity between the non-fixed portion 20N and the fixed portion 20F. Therefore, the maximum thickness 22T is more preferably 1.1 times or more, more preferably 1.5 times or more the maximum thickness of the shaft 10. The maximum thickness 22T of the reinforcing portion 22 is the total maximum thickness of the thickness of the reinforcing member and the thickness of the balloon 20 when the reinforcing portion 22 is provided with the reinforcing member. Further, the maximum thickness 10T of the shaft 10 is the total maximum thickness of the thickness of the shaft 10 and the thickness of the protruding portion 13 when the shaft 10 includes the protruding portion 13.

In the radial cross section of the balloon 20, the maximum thickness 22T of the reinforcing portion 22 is preferably smaller than the maximum outer diameter 10D of the shaft 10. This improves the handleability of the balloon catheter 1. Further, this makes it easier to bend the shaft 10 to some extent so that the reinforcing portion 22 is on the outside, so that the reinforcing portion 22 can be hooked on the lesion portion or the calcified lesion can be cracked by the reinforcing portion 22. It can be made easier. As described above, in the balloon catheter 1, the reinforcing portion 22 not only suppresses the curvature of the balloon 20 at the time of expansion, but also leaves the curvature of the balloon 20 at the time of expansion to some extent, and utilizes the curvature to the reinforcing portion. The 22 may be used to crack a highly stenotic lesion or a calcified lesion, or the reinforcing portion 22 may exhibit an anti-slip function or the like. The maximum outer diameter 10D of the shaft 10 corresponds to the total maximum length of the outer diameter of the shaft 10 and the thickness of the protruding portion 13 when the shaft 10 includes the protruding portion 13.

As shown in FIGS. 9 and 10, the reinforcing portion 22 may have a hole 22H extending in the perspective direction X. Further, the reinforcing portion 22 may have an opening 22O which is distal to the proximal end 22A of the reinforcing portion 22 and communicates with the hole 22H on the proximal side of the distal end 22B of the reinforcing portion 22. .. With these configurations, the linear portion 31 of the elongated body 30 as shown in FIG. 13 is on the proximal side, the blade portion 32 is on the distal side, and the elongated body 30 is inserted into the hole 22H to open the opening 22O. The blade portion 32 can be exposed from the above. As a result, the blade portion 32 can be easily brought into contact with the lesion portion, so that the reinforcing portion 22 can easily make a crack in a highly stenotic lesion or a calcified lesion. Further, as a result, it is possible to make it easier for the reinforcing portion 22 to exert a non-slip function or the like. Further, the drug may be injected into the body through the opening 22O via the hole 22H. The drug is not particularly limited as long as it is a pharmacologically active substance, and examples thereof include drugs that are acceptable as pharmaceuticals such as non-gene therapy drugs, biomolecules, small molecules, and cells. More specifically, anti-restenotic agents such as antiproliferative agents and immunosuppressive agents can be mentioned. As the drug, only one kind may be used, or two or more kinds may be used.

It is preferable that the long body 30 is slidably arranged in the hole 22H. Thereby, the strength of the rigidity of the reinforcing portion 22 can be adjusted, and the curvature of the balloon 20 can be easily controlled.

The elongated body 30 preferably includes a linear portion 31 and a blade portion 32. For the material constituting the long body 30, the description of the material of the reinforcing portion 22 can be referred to.

Examples of the shape of the blade portion 32 in the cross section in the thickness direction include a polygonal shape such as a triangle shape, a rectangular shape, and a trapezoidal shape, a hemispherical shape, and a spherical shape. Of these, a polygonal shape is preferable, and a triangular shape is more preferable. Further, the blade portion 32 may be notched in the thickness direction.

Examples of the shape of the linear portion 31 in the cross section in the thickness direction include a polygonal shape such as a triangle shape, a rectangular shape, and a trapezoidal shape, a hemispherical shape, and a spherical shape. Of these, a polygonal shape is preferable, and a rectangular shape is more preferable.

The inner tube 11 of the shaft 10 is at least one selected from the group consisting of, for example, a polyamide resin, a polyester resin, a polyurethane resin, a polyolefin resin, a fluorine resin, a vinyl chloride resin, a silicone resin, and a natural rubber. It may contain seeds. Moreover, you may use an elastomer resin as these resins.

The outer tube 12 of the shaft 10 is at least one selected from the group consisting of polyamide-based resin, polyester-based resin, polyurethane-based resin, polyolefin-based resin, fluorine-based resin, vinyl chloride-based resin, silicone-based resin, and natural rubber. May include. Moreover, you may use an elastomer resin as these resins. The outer pipe 12 is not limited to one, and two or more outer pipes 12 may be connected and used. When connecting two or more, it is preferable to connect them in the axial direction. The outer pipe 12 may include a lumen extending in the perspective direction X communicating with the hole 22H of the reinforcing portion 22 as shown in FIG.

Further, the inner pipe 11 and the outer pipe 12 may have a braided body in which the wire rod is braided, a coil body in which the wire rod is spirally wound, or the like. As a result, the strength of the inner pipe 11 and the outer pipe 12 can be easily improved. Examples of the wire include metal wire and fiber. As the material constituting the metal wire, for example, stainless steel, titanium, nickel-titanium alloy, cobalt-chromium alloy, tungsten alloy and the like are preferable. The metal wire may be a single wire or a stranded wire. Examples of the fiber include polyarylate fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, PBO fiber, carbon fiber and the like. The fibers may be monofilaments or multifilaments.

The inner tube 11 and the outer tube 12 may include an X-ray impermeable portion containing an X-ray impermeable substance. As the X-ray impermeable substance, at least one selected from the group consisting of, for example, lead, barium, iodine, tungsten, gold, platinum, iridium, platinum iridium alloy, stainless steel, titanium, cobalt-chromium alloy, palladium, and tantalum is selected. Can be mentioned.

As shown in FIGS. 1, 11 and the like, it is preferable to have the balloon catheter 1 and the handle portion 40 on the proximal side. The handle portion 40 preferably has a space communicating with the space between the inner tube 11 and the outer tube 12, which is a flow path for injecting a fluid into the pressurized inner tube 20I of the balloon 20. .. The balloon catheter 1 is a rapid exchange type (RX type) in which a guide wire can be inserted from the proximal end 11A of the inner tube 11 provided on the distal side of the handle portion 40. However, the balloon catheter 1 is an over-the-wire type (OTW type) in which the proximal end 11A of the inner tube 11 is located in the handle portion 40 and the guide wire can be inserted from the proximal end to the distal end. There may be.

1 Balloon catheter 10 Shaft 10T Shaft maximum thickness 10C Shaft central axis 10D Shaft maximum outer diameter 11 Inner tube 12 Outer tube 13 Protruding part 20 Balloon 20A Proximal end of balloon 20B Distal end of balloon 20C Central axis of balloon 20F Fixed part 20I Pressurized lumen 20N Non-fixed part 20P Balloon protruding thick part 20T Balloon hill-shaped thick part 20R Balloon rail-shaped thick part 20a Proximal side sticking part 20b Distal sticking Part 20X Proximal end of proximal fixation 20Y Proximal end of distal fixation 20c Midway 21a Proximal taper 21c Straight tube 21b Distal taper 22 Reinforcement 22A Proximal end of reinforcement 22B Distal end of reinforcement 22H Hole extending in perspective 22O Opening communicating with hole 22T Maximum thickness of reinforcement 30 Long body 31 Linear part 32 Blade part 40 Handle part 100 Conventional balloon catheter

Claims (16)

A balloon catheter including a shaft extending in the perspective direction and a balloon provided on the distal side of the shaft.
The proximal end of the balloon is anchored to the shaft by a proximal anchoring portion.
The distal end of the balloon is anchored to the shaft by a distal anchoring portion.
The balloon is distal to the distal end of the proximal fixation, and the balloon is directly to the shaft in the middle of the proximal end of the distal fixation. Alternatively, it has a fixed portion that is indirectly fixed and a non-fixed portion in which the balloon is not fixed to the shaft.
The non-fixed portion has a reinforcing portion and
A balloon catheter characterized in that the fixed portion and the reinforcing portion are separated from each other by 1/4 or more of the peripheral length in the circumferential direction of the balloon. The balloon catheter according to claim 1, wherein the shaft is located outside the balloon. The balloon catheter according to claim 2, wherein the shaft is provided with a protruding portion protruding toward the side opposite to the balloon in the middle portion. The balloon catheter according to claim 1, wherein the shaft is located inside the balloon. The balloon catheter according to claim 4, wherein the shaft includes a protruding portion that projects toward the fixed portion side. The balloon catheter according to claim 4 or 5, wherein the central axis of the shaft is located closer to the fixed portion side than the central axis of the balloon. The balloon catheter according to any one of claims 1 to 6, wherein the reinforcing portion is formed by a thick portion of the balloon. The balloon catheter according to any one of claims 1 to 7, wherein the reinforcing portion includes a reinforcing member. The balloon catheter according to any one of claims 1 to 8, wherein the maximum thickness of the reinforcing portion in the radial cross section of the balloon is equal to or larger than the maximum thickness of the shaft. The balloon catheter according to any one of claims 1 to 8, wherein the maximum thickness of the reinforcing portion in the radial cross section of the balloon is smaller than the maximum outer diameter of the shaft. The balloon catheter according to any one of claims 1 to 10, wherein the balloon includes a straight tube portion extending in the axial direction of the shaft, and the fixing portion is located in the straight tube portion. The balloon has a proximal taper portion that expands in diameter toward the distal side, a straight tube portion, and a distal taper portion that contracts in diameter toward the distal side, and the reinforcing portion is at least The balloon catheter according to any one of claims 1 to 11, which is located in the proximal taper portion, the straight tube portion, and the distal taper portion. The balloon cutter according to any one of claims 1 to 12, wherein the reinforcing portion has a long shape. The balloon catheter according to any one of claims 1 to 13, wherein the reinforcing portion has a hole extending in the perspective direction. The balloon catheter according to claim 14, wherein the reinforcing portion is distal to the proximal end of the reinforcing portion and has an opening communicating with the hole on the proximal side of the distal end of the reinforcing portion. The balloon catheter according to claim 14 or 15, wherein a long body is slidably arranged in the hole.

Images