JP2013056070A - Method of manufacturing balloon catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a balloon catheter which is suitably pulled from the inside of the body.SOLUTION: The balloon catheter includes an outside tube and a balloon 13. The balloon 13 has a proximal side leg area joined to a distal end side of the outside tube and a proximal side cone area which is formed by being diametrically enlarged from the distal end part of the leg area to the distal side. The balloon catheter is manufactured by performing a dilation step of dilating the balloon 13 and a blade formation step of moving a plurality of pressurizing members 33 arranged around a dilated dilation/contraction part of the balloon 13 to a prescribed position in a radial-direction inside of the dilation/contraction part and crushing the dilated dilation/contraction part of the balloon 13 by the respective pressurizing members 33, thereby projecting a part of the dilation/contraction part to the radial-direction outside between the respective pressurizing members 33 and forming a plurality of blades 25. In this case, the prescribed position is set at a position at which the diameter of a virtual inscribed circle inscribed in the non-facing pressurizing surfaces 33c of the respective pressurizing members 33 is smaller than the outer diameter of the proximal side leg area.

Description

  The present invention relates to a method for manufacturing a balloon catheter.

  Conventionally, balloon catheters are sometimes used in treatments such as PTA (percutaneous angioplasty) and PTCA (percutaneous coronary angioplasty) (see, for example, Patent Document 1). The balloon catheter is provided with a balloon that can be inflated and deflated on the distal end side thereof, and the balloon is expanded by introducing and inflating the balloon to a treatment target site that is narrowed or occluded in the body. . In addition, the balloon catheter is introduced to a treatment target site through a lumen of a sheath introducer or a guiding catheter introduced in advance into the body, for example.

  FIG. 10 shows an example of a balloon catheter. A balloon catheter 80 shown in FIG. 10 includes a catheter tube 81 and a balloon 82, and the catheter tube 81 includes an outer tube 83 and an inner tube 84 inserted through the outer tube 83. The inner tube 84 is provided in a state extending to the distal side from the outer tube 83, and a balloon 82 is provided so as to cover the extended region from the outside.

  The balloon 82 has joints at both ends joined to the catheter tube 81, and an expansion / contraction part that is provided between the joints and expands and contracts. Specifically, the balloon 82 includes a proximal leg region 82a joined to the outer tube 83 and a proximal cone region tapered so that the inner diameter and the outer diameter increase toward the distal end side. 82b, the straight tube region 82c having the same inner diameter and outer diameter in the entire length direction and forming the maximum outer diameter region of the balloon 82, and the inner diameter and the outer diameter are reduced toward the distal end side. In this order, the distal cone region 82d and the distal cone region 82e joined to the inner tube 84 are arranged in this order from the proximal side. The tube region 82c and the distal cone region 82d constitute an expansion / contraction part.

  In general, the balloon 82 includes a plurality of wings formed in the contracted state. These wings are formed in the expansion / contraction part of the balloon 82, and when the balloon 82 is in a deflated state, the wings are folded along the circumferential direction of the inner tube 84 and wound around the tube 84. Thereby, the diameter of the balloon 82 is reduced, and after the expansion treatment by the balloon catheter 80 is completed, the balloon 82 can be easily pulled out from the blood vessel.

  As a method for forming this kind of wings in the balloon 82 (specifically, an inflating and contracting portion), a plurality of pressing members arranged around the inflated balloon 82 are moved toward the inside in the radial direction of the balloon 82. In addition, there is known a method of forming a wing by causing a part of the balloon 82 to protrude between the pressing members by being crushed by the pressing surfaces of the pressing members.

JP 2008-237844 A

  By the way, when wings are formed on the balloon 82 by the above-described method, for example, each pressing is performed until the diameter of a virtual inscribed circle inscribed in the pressing surface of each pressing member is the same as the outer diameter of the proximal leg region 82a. The member is moved radially inward of the balloon.

  However, in such a configuration, a part of the proximal end side of the proximal cone region 82b whose outer diameter approximates the outer diameter of the proximal leg region 82a in the expansion / contraction part of the balloon 82 is caused by the pressing member. There is a possibility that the wings are not formed without being sufficiently pressed. In that case, the wings are not sufficiently folded in the proximal cone region 82b, and a part of the wings may be lifted. Then, when the balloon catheter 80 is pulled out from the sheath introducer or guiding catheter, the balloon 82 becomes a great resistance, and there is a possibility that the pulling out operation cannot be performed suitably.

  This invention is made | formed in view of the said situation, and it aims at providing the manufacturing method of the balloon catheter which can perform the extraction | drawer operation | work from a body suitably.

  In order to solve the above-described problem, a balloon catheter manufacturing method according to a first aspect of the present invention includes a fluid tube having a fluid lumen for circulating a fluid, and a proximal side joint joined to a distal end side of the tube. Expansion that expands or contracts when a fluid is circulated through the fluid lumen, including a portion and a proximal-side enlarged portion that is expanded from the distal end of the joint toward the distal side. In a method for manufacturing a balloon catheter comprising a balloon having a contraction part, an inflating step for inflating the balloon, and a plurality of pressing members disposed around the inflating / contraction part inflated in the balloon By moving to the predetermined position toward the inner side in the radial direction of the expansion / contraction part and crushing by the respective pressing members, a part of the expansion / contraction part is directed to the outer side in the radial direction between the respective pressing members. Wing forming step of forming a plurality of wings, and the predetermined position is assumed to be a virtual inscribed circle inscribed in the pressing surface that presses the expansion / contraction portion in the radial direction in each pressing member The imaginary inscribed circle is set at a position where the diameter of the virtual inscribed circle is smaller than the outer diameter of the proximal joint, and the plurality of wings are formed in the inflated and deflated portion in the deflated state of the balloon. It is folded along the circumferential direction of the balloon.

  According to the present invention, in a state where the balloon is inflated, the expansion / contraction portion of the balloon is crushed toward the radially inner side by the plurality of pressing members, whereby a plurality of wings are formed in the expansion / contraction portion. At this time, each pressing member moves to a predetermined position where the diameter of a virtual inscribed circle inscribed in each pressing surface is smaller than the outer diameter of the proximal joint portion of the balloon. A region having a larger outer diameter than the joint portion, for example, the entire region of the proximal-side enlarged portion can be pressed by the pressing member. Thereby, since a wing | blade can be formed over the whole region of a proximal side enlarged diameter part, the folding performance of a wing | blade can be improved in a proximal side enlarged diameter part. Therefore, in this case, when the balloon catheter is pulled out from the body, it is possible to suppress the balloon from becoming resistance, and the pulling out operation from the body can be suitably performed.

  In particular, when the balloon is pulled out from the body, the proximal diameter-expanded portion tends to become a resistance in the balloon. Therefore, the above-described configuration that suppresses resistance of the enlarged diameter portion by increasing the folding performance of the wing of the proximal enlarged diameter portion is effective in reducing the drawing resistance of the balloon.

  In general, the expansion / contraction part of the balloon is provided with an effective expansion part continuously provided on the distal side of the proximal enlarged part and having the largest outer diameter in the balloon, in addition to the proximal enlarged part. ing. Here, the wall thickness of the balloon may be larger in the proximal-side expanded portion than in the expanded effective portion, and in this case, the wings are less likely to be formed in the proximal expanded portion than in the expanded effective portion. It is thought that it has become. In this regard, in the present invention, the configuration is such that the expansion / contraction part is crushed by moving the pressing member to a position where the diameter of the virtual inscribed circle is smaller than the outer diameter of the proximal side joint. Compared to the configuration in which the pressing member is moved to a position where the diameter of the circle is the same as the outer diameter of the proximal joint, there is also an advantage that wings can be suitably formed in the proximal enlarged portion.

  The method for manufacturing a balloon catheter according to a second aspect of the invention is the arrangement step of arranging the balloon in a balloon arrangement region which is an inner region surrounded by the plurality of pressing members before the wing formation step in the first invention. In the placing step, the balloon is placed in the axial direction so that the boundary between the proximal joint and the expansion / contraction part is at the same position as or closer to the end of the pressing surface of the pressing member. It arrange | positions so that it may be located in the position side, and the said wing formation process crushes the expansion-contraction part of the said balloon arrange | positioned by the said arrangement | positioning process with each said pressing member.

  According to the present invention, when the expansion / contraction part is crushed by the pressing member so as to form a wing on the expansion / contraction part, it is possible to avoid the proximal side joint from being pressed by the member. Therefore, the effect of the first invention can be obtained while preventing the proximal side joint from being crushed or damaged.

  The method for manufacturing a balloon catheter according to a third aspect of the present invention further comprises a joining step of joining the proximal side joining portion and the fluid tube before the expansion step in the first or second invention, In the joining step, joining the proximal joint and the fluid tube so that a part of the distal joint of the proximal joint is a non-joined region that is not joined to the fluid tube. Features.

  When the expansion / contraction part is crushed by the pressing member to form a wing on the balloon, the proximal side joint part joined to the fluid tube is pulled to the side of the expansion / contraction part along with the crushing. There is a concern that inconveniences such as disconnection of the joint from the fluid tube may occur. In particular, in the above-described configuration in which each pressing member is moved and the expansion / contraction portion is crushed until the virtual inscribed circle in contact with the pressing surface of each pressing member becomes smaller than the outer diameter of the proximal joint portion, there is a concern about the above-described configuration. Rise. Therefore, in the present invention, in view of this point, for example, the fluid tube is overlapped inside and outside only at a part of the proximal side joint portion, and the proximal side joint portion and the fluid tube are joined in the overlapping state, A non-joining region that is not joined to the fluid tube is provided at the proximal joint. As a result, when the expansion / contraction part is crushed by the pressing member, the non-joining region is deformed such that the non-joining region is stretched, so that the proximal joint portion is pulled to the region joined to the fluid tube (joining region). It is possible to suppress the action of force. Therefore, the above inconvenience can be suppressed.

  According to a fourth aspect of the present invention, there is provided a balloon catheter manufacturing method according to any one of the first to third aspects, wherein the pressing member is provided so as to be rotatable about a rotation axis extending in the same direction as the axial direction of the balloon. The balloon is moved inward in the radial direction by the rotation.

  In the first to third inventions, for example, as the pressing member, a rotating pressing member that moves inward in the radial direction of the balloon by rotating may be used. Here, when the expansion / contraction part is crushed using such a rotary pressing member, it is assumed that a force in the outer peripheral direction acts on the outer peripheral surface of the expansion / contraction part, and in that case, the force acts on the proximal side joint part. It is considered that the tensile force to be increased is likely to cause inconvenience that the joint portion is detached from the fluid tube. In view of this point, it is desirable to apply the third aspect of the invention when using the rotary pressing member, and the above-described disadvantages can be suitably suppressed.

  The balloon catheter manufacturing method according to a fifth aspect of the present invention is the method for manufacturing a balloon catheter according to any one of the first to fourth aspects, wherein the fluid tube is inserted inside the fluid tube in a state where a part of the fluid catheter extends more distally than the tube. An inner shaft, wherein the balloon is applied to a balloon catheter that is joined to the extended extension portion of the inner shaft and includes a distal joint having a smaller outer diameter than the proximal joint; The predetermined position is set to a position where the diameter of the virtual inscribed circle is smaller than the outer diameter of the proximal joint and larger than the outer diameter of the distal joint. .

  According to the present invention, when forming a wing on the balloon, each pressing member is moved to a position where the diameter of a virtual inscribed circle inscribed in the pressing surface of each pressing member is larger than the outer diameter of the distal side joint. Since it is set as the structure to which it moves, it can avoid that each press member bites into a distal side junction part. Thereby, the effect of 1st invention can be acquired, aiming at the damage prevention to a distal side junction part. Further, in the present invention, the tensile force acting on the proximal joint is compared with the case where each pressing member is moved until the diameter of the virtual inscribed circle becomes smaller than the outer diameter of the distal joint when the wing is formed. Can be suppressed. Therefore, inconveniences such as the proximal-side joint portion coming off from the fluid tube can be suppressed.

1 is a schematic overall side view showing the configuration of a balloon catheter. The longitudinal cross-sectional view of a balloon and an outer tube. The cross-sectional view which shows a balloon and its periphery. The front view of a wing forming apparatus. The figure which shows a mode that a wing | wing is formed with a wing | blade formation apparatus. The figure which shows the state which has arrange | positioned the balloon to the wing | blade formation apparatus. The figure which shows a folding apparatus. The figure which shows the measurement result which measured the pulling-out force of a balloon. The front view which shows another form of a wing | blade formation apparatus. Sectional drawing which shows the structure of the balloon periphery of the conventional balloon catheter.

  Hereinafter, an embodiment of a balloon catheter will be described with reference to the drawings. First, a schematic configuration of the balloon catheter 10 will be described with reference to FIG. FIG. 1 is a schematic overall side view showing the configuration of the balloon catheter 10.

  As shown in FIG. 1, the balloon catheter 10 includes a catheter tube 11, a hub 12 attached to a proximal end portion (base end portion) of the catheter tube 11, and a distal end side (tip side) of the catheter tube 11. ) Attached to the balloon 13.

  The catheter tube 11 is composed of a plurality of tubes, and has an inner and outer multi-tube structure from at least an intermediate position in the axial direction (longitudinal direction) to the position of the balloon 13. Specifically, the catheter tube 11 includes an outer tube 15 and an inner tube 16 having an inner diameter and an outer diameter smaller than the outer tube 15, and the inner tube 16 is inserted into the outer tube 15. Thus, it has an inner and outer double pipe structure. Here, the outer tube 15 corresponds to a fluid tube, and the inner tube 16 corresponds to an inner shaft.

  The outer tube 15 is formed in a tubular shape having outer tube holes 21 (see FIG. 2) that are continuous over the entire axial direction and open at both ends. The outer tube 15 includes an outer proximal tube 22 that forms a predetermined range from a position continuous with the hub 12 toward the distal side, and an outer distal tube 23 that forms a distal side. The outer proximal tube 22 is made of a metal such as a Ni—Ti alloy or stainless steel, and the outer distal tube 23 is made of a thermoplastic polyamide so as to be less rigid than the outer proximal tube 22. Yes. The outer proximal tube 22 may be made of a synthetic resin. Further, the material for forming the outer distal tube 23 is not limited to thermoplastic polyamide, and may be other thermoplastic resin.

  The inner tube 16 is formed in a tubular shape having inner tube holes 29 (see FIG. 2) that are continuous over the entire axial direction and open at both ends. The inner tube 16 has a proximal end joined to an intermediate position in the axial direction of the outer tube 15, specifically, a boundary between the outer proximal tube 22 and the outer distal tube 23. Further, the inner tube 16 is provided in a state where a part thereof extends to the distal side of the outer tube 15, and the balloon 13 is provided so as to cover the extended region from the outside. Yes.

  The outer tube hole 21 of the outer tube 15 functions as a fluid lumen through which the compressed fluid flows when the balloon 13 is inflated or deflated. The inner tube hole 29 of the inner tube 16 functions as a guide wire lumen through which the guide wire G is inserted. Further, the proximal end opening 29a of the inner tube hole 29 exists at a midway position in the axial direction of the balloon catheter 10, and therefore the present balloon catheter 10 is configured as a so-called RX type catheter. However, the present invention is not limited to this, and a so-called over-the-wire type catheter in which the proximal end opening 29 a of the inner lumen 29 is present at the proximal end portion of the balloon catheter 10 may be used.

  Next, the structure of the balloon 13 and its periphery will be described with reference to FIGS. 2 is a longitudinal sectional view of the balloon 13 and the outer tube 15, and FIG. 3 is a transverse sectional view showing the balloon 13 and its periphery. 2 shows the inflated state of the balloon 13, and FIG. 3 shows the deflated state of the balloon 13. FIG. 3 is a cross-sectional view of the straight tube region 13 c of the balloon 13.

  As shown in FIG. 2, the balloon 13 covers the region extending from the outer side of the inner tube 16 to the distal side of the outer tube 15 (hereinafter, this region is referred to as the “extending region 18”) from the outside. The proximal end is joined to the distal end of the outer tube 15 (specifically, the outer distal tube 23), and the distal end is connected to the inner tube 16 (specifically, the extension region 18). It is joined to the distal end side.

  The balloon 13 is made of a thermoplastic polyamide elastomer. However, it is not limited to polyamide elastomer as long as it can expand and contract well with fluid supply and discharge, and other thermoplastic resins may be used, such as polyethylene, polyethylene terephthalate, polypropylene, polyurethane, Polyamide, polyimide, polyimide elastomer, silicon rubber, etc. can also be used. Moreover, the compound for exhibiting a desired function and another polymer may be added with respect to the said thermoplastic resin.

  The balloon 13 has joint portions at both ends joined to the catheter tube 11, and an expansion / contraction portion that is provided between the joint portions and expands and contracts. Specifically, the balloon 13 has a proximal leg region 13a joined to a distal end portion of the outer tube 15 (outer distal tube 23), and an inner diameter and an outer diameter continuously toward the distal side. A proximal cone region 13b that is tapered so as to be expanded, a straight tube region 13c that has the same inner diameter and outer diameter in the entire length direction and that forms the maximum outer diameter region of the balloon 13, A distal cone region 13d that is tapered so that the inner diameter and the outer diameter are continuously reduced toward the distal side, and a distal leg region 13e that is joined to the extension region 18 of the inner tube 16; In this order from the proximal side. Here, the proximal leg region 13a corresponds to the proximal joint portion, the proximal cone region 13b corresponds to the proximal enlarged portion, the straight tube region 13c corresponds to the expansion effective portion, The distal leg region 13e corresponds to the distal joint. Further, an expansion / contraction part is configured by the proximal cone region 13b, the straight tube region 13c, and the distal cone region 13d.

  Both the proximal leg region 13a and the distal leg region 13e have a cylindrical shape, and the proximal leg region 13a has an outer diameter larger than that of the distal leg region 13e. In the present embodiment, the outer diameter of the proximal leg region 13a is 1.5 mm, whereas the outer diameter of the distal leg region 13e is 1.2 mm.

  Inside the proximal leg region 13a, an outer tube 15 is inserted and joined. The outer tube 15 is inserted into the proximal leg region 13a so that the distal end thereof is positioned at the intermediate portion in the axial direction of the proximal leg region 13a, more specifically, at the central portion. The region 13a is joined by thermal welding. Thereby, a part of the proximal leg region 13 a is a non-joined region 28 that is not joined to the outer tube 15. However, the non-joining region 28 is not necessarily provided in a part of the proximal leg region 13a, and the outer tube 15 may be joined to the entire region 13a. Further, the inner tube 16 (extension region 18) is joined inside the distal leg region 13e. The inner tube 16 is joined to the distal leg region 13e by thermal welding.

  In addition, the thickness of the balloon 13 (specifically, the expansion / contraction part) is larger in the proximal cone region 13b and the distal cone region 13d than in the straight tube region 13c. Specifically, the thickness of the straight tube region 13c is 0.030 mm, whereas the thicknesses of the proximal cone region 13b and the distal cone region 13d are 0.038 mm in the central portion in the axial direction, It is 0.037 mm. More specifically, the thickness of the proximal cone region 13b increases from the end on the straight tube region 13c side toward the end on the proximal leg region 13a side in the region 13b. It is functionally large. The proximal leg region 13a has a thickness of 0.26 mm. On the other hand, the thickness of the distal cone region 13d increases from the end on the straight tube region 13c side toward the end on the distal leg region 13e side in the region 13d. Is getting bigger. In the distal leg region 13e, the wall thickness is 0.23 mm. In other words, the thickness of each cone region 13b, 13d increases at a stretch toward the boundary in the vicinity of the boundary with the leg regions 13a, 13e.

  The balloon 13 is inflated when a fluid is pressurized and supplied into the balloon 13 through the outer tube hole 21 of the outer tube 15, and a negative pressure is applied to the outer tube hole 21, so that the fluid flows from the balloon 13. When discharged, it is in a contracted state. As shown in FIG. 3, the balloon 13 includes a plurality (three in FIG. 3) of wings 25 formed in the contracted state. These wings 25 are provided in the circumferential direction of the balloon 13 at a predetermined interval (specifically, at equal intervals). Each wing 25 is formed so as to extend in the axial direction in the expansion / contraction portion (proximal cone region 13b, straight tube region 13c, and distal cone region 13d) of the balloon 13, and more specifically in the expansion / contraction portion. It is formed continuously from the proximal end (proximal end of the proximal cone region 13b) to the vicinity of the distal end (distal end of the distal cone region 13d). When the balloon 13 is in a deflated state, the wings 25 are each folded in the circumferential direction of the balloon 13 and wound around the inner tube 16.

  The number of wings 25 formed on the balloon 13 in the contracted state is not limited to three, but may be two, four, five, or six.

  Two contrast rings 27 made of stainless steel are attached to the outer peripheral surface of the extension region 18 of the inner tube 16. The contrast ring 27 is for improving the visibility of the balloon 13 under X-ray projection and easily aligning the balloon 13 with the target treatment site.

  Next, the manufacturing procedure of the balloon catheter 10 will be described. Here, the procedure for forming the wings 25 on the balloon 13 will be mainly described.

  First, a balloon manufacturing process for manufacturing the balloon 13 is performed. In this step, a tubular parison that is the basis of the balloon 13 is first produced by extrusion. Next, the tubular parison is stretched in the length direction, and then blow-molded under predetermined conditions using a mold in which a mold corresponding to the shape of the balloon 13 is formed. Thereby, the tubular parison is in a state of being biaxially stretched. Then, the manufacture of the balloon 13 is completed by cutting both ends of the stretched tubular parison. By manufacturing the balloon 13 in such a procedure, the thickness of each cone region 13b, 13d of the balloon 13 increases from the end on the straight tube region 13c side toward the end on the leg region 13a, 13e side. It becomes.

  Next, a proximal side joining step (corresponding to a joining step) for joining the proximal leg region 13a of the balloon 13 to the distal end portion of the outer tube 15 (specifically, the outer distal tube 23) is performed. In this step, the outer tube 15 is inserted into the proximal leg region 13a so that the distal end of the tube 15 is located at the center of the proximal leg region 13a. The side leg region 13a is joined by thermal welding. Thereby, the non-joining area | region 28 is provided in the proximal side leg area | region 13a. Note that the joining method is not necessarily limited to thermal welding, and other joining methods such as adhesion with an adhesive may be employed.

  Next, a distal side joining step of joining the distal end side of the inner tube 16 (extension region 18) to the distal leg region 13e of the balloon 13 to which the outer tube 15 is joined is performed. In this step, the inner tube 16 is inserted into the outer tube hole 21 of the outer tube 15 and the inside of the balloon 13, and the inner tube 16 and the distal leg region 13e are joined by thermal welding in the inserted state. Note that the joining method is not necessarily limited to thermal welding, and other joining methods such as adhesion with an adhesive may be employed.

  Next, an inflating step for inflating the balloon 13 by applying pressure to the balloon 13 is performed. In this step, the balloon 13 is brought into a predetermined inflated state, that is, an inflated state when the balloon 13 is used (all inflated state). As a pressure applied to the balloon 13, for example, 0.15 to 0.2 MPa is assumed.

  Subsequently, a balloon placement step (corresponding to the placement step) in which the balloon 13 is set (placed) in the wing forming device 30 for forming the wing 25 on the balloon 13, and the wing 25 is placed on the balloon 13 using the wing forming device 30. The wing formation process to form is performed. Hereinafter, each of these steps will be described with reference to FIGS. 4 is a front view of the wing forming apparatus 30, FIG. 5 is a view showing how the wing 25 is formed using the wing forming apparatus 30, and FIG. 6 is a view showing a state in which the balloon 13 is arranged on the wing forming apparatus 30. .

  As shown in FIG. 4, the wing forming device 30 includes a base plate 31 having a circular opening 32 and a plurality (three in FIG. 4) around the central axis of the opening 32 in a front view of the plate 31. And a pressing member 33 provided. These pressing members 33 are formed so as to extend from the opening edge portion of the opening portion 32 in the base plate 31 toward the central axis side of the opening portion 32, and the rotation shaft portion 35 disposed on the opening edge portion. It is pivotally supported via the shaft. The pressing member 33 has a flat plate shape having a plate surface parallel to the plate surface of the base plate 31, and the thickness thereof is larger than the entire length (length in the axial direction) of the balloon 13.

  An inner area surrounded by each pressing member 33 is an arrangement area 37 in which the balloon 13 is arranged. Here, to supplement the pressing members 33, the pressing members 33 are radially arranged at equal intervals around the central axis A <b> 1 of the arrangement region 37, and each of them presses the central axis A <b> 2 of the rotating shaft portion 35. It is pivotable as a center. In this case, the size of the arrangement region 37 is changed by the rotation of each pressing member 33 about the central axis A2. In the present embodiment, the center axis A1 of the arrangement region 37 and the center of the opening 32 are configured to coincide with each other. Further, when the balloon 13 is arranged in the arrangement region 37, the central axis of the balloon 13 (that is, the central axis of the inner tube 16) coincides with the central axis A1 of the arrangement region 37, and in this state, the outer peripheral portion of the balloon Is crushed to form wings.

  The pressing member 33 has a first pressing surface 33a and a second pressing surface that press the outer peripheral surface of the balloon 13 (specifically, the balloon before wing formation) arranged in the arrangement region 37 at the end of the rotating tip. 33b is formed. Each of the pressing surfaces 33a and 33b has an arc shape when viewed from the direction of the central axis A1 of the arrangement region 37 (the front surface of the base plate 31), and the first pressing surface 33a is formed in a concave arc shape. On the other hand, the second pressing surface 33b is formed in a convex arc shape. However, these pressing surfaces 33a and 33b do not necessarily have an arc shape, and some or all of them may be planar. The pressing surfaces 33a and 33b are opposed to different pressing members 33, respectively. That is, in FIG. 4, the first pressing surface 33a faces the second pressing surface 33b of the pressing member 33 located in the counterclockwise direction of the drawing, and the second pressing surface 33b is the pressing member 33 positioned in the clockwise direction of the drawing. It faces the first pressing surface 33a. Each of the pressing surfaces 33a and 33b has a length dimension that is at least larger than the balloon length (the length from the distal end to the proximal end of the balloon 13) in the direction of the central axis A1.

  Each pressing surface 33a, 33b forms a wing 25 by crushing the balloon 13 in a gap between the both pressing surfaces 33a, 33b, and a predetermined interval (of wing formation) is formed on each pressing surface 33a, 33b. The facing portions that are opposed to each other at an interval) are wing forming surfaces. Here, a part of the first pressing surface 33a is a non-facing surface portion that does not face the second pressing surface 33b, and at the time of wing formation, the non-facing surface portion causes the expansion / contraction portion of the balloon 13 (both cone regions). 13b, 13d and straight pipe region 13c) are pressed toward the central axis A1. Hereinafter, the non-facing surface portion of the first pressing surface 33a is referred to as a “non-facing pressing surface 33c”. The non-opposing pressing surface 33c corresponds to “a pressing surface that presses the expansion / contraction portion inward in the radial direction”.

  Each pressing member 33 has an initial position shown in FIG. 5 (a) (and FIG. 4) and a wing formation position shown in FIG. 5 (b) by turning around the central axis A2 of the turning shaft portion 35. It is possible to move between. Each pressing member 33 is rotated in synchronization with the same side by a driving device such as a motor (not shown).

  When each pressing member 33 moves from the initial position to the wing formation position, each non-opposing pressing surface 33c is directed toward the central axis A1 side of the arrangement area 37 (that is, radially inside the balloon 13 arranged in the arrangement area 37). Displace. Specifically, assuming a virtual inscribed circle X (indicated by a one-dot chain line in FIG. 4) inscribed in the non-opposing pressing surface 33 c of each pressing member 33, the diameter of the virtual inscribed circle X is the pressing member 33. Is slightly larger than the outer diameter of the straight tube region 13 c of the balloon 13, and is larger than the outer diameter of the distal leg region 13 e of the balloon 13 and the proximal leg at the wing forming position of the pressing member 33. The outer diameter of the region 13a is smaller. In the following description, the diameter of the virtual inscribed circle X when the pressing member 33 is at the wing formation position is referred to as a balloon crushing diameter D. In this embodiment, the balloon crushing diameter D is set to 1.24 mm. . Further, when each pressing member 33 moves from the initial position to the wing forming position, the adjacent pressing members 33 approach each other and the gaps between the pressing members 33, more specifically, the pressing surfaces 33 a and 33 b facing each other in the pressing members 33. The gap between the wing-forming surfaces (more specifically) is reduced.

  4 is a circular frame provided so as to surround the opening 32 in the base plate 31. The above is the description of the wing forming apparatus 30.

  Returning to the description of the manufacturing procedure, in the balloon placement step, the balloon 13 is placed in the placement region 37 of the wing forming apparatus 30 as shown in FIG. At this time, each pressing member 33 is in the initial position. In this case, as shown in FIG. 6, the boundary portion between the proximal leg region 13 a and the proximal cone region 13 b in the balloon 13 (the boundary portion between the expansion / contraction portion and the proximal non-expansion / contraction portion) is used. The balloon 13 is placed in the placement region 37 in a state of being aligned with the end of the pressing member 33 in the thickness direction. Thereby, in the balloon 13, the proximal cone region 13 b, the straight tube region 13 c, the distal cone region 13 d and the distal leg region 13 e are arranged in the arrangement region 37, and the proximal leg region 13 a is arranged in the arrangement region 37. Placed outside. In addition, you may perform this process before an expansion process.

  Next, a wing formation process is performed to form wings 25 on the expansion / contraction part of the balloon 13 (proximal cone region 13b, straight tube region 13c, and distal cone region 13d). In this step, each pressing member 33 is moved from the initial position to the wing forming position, and the inflating / shrinking portion of the balloon 13 is crushed by the non-opposing pressing surface 33c of each pressing member 33, thereby partially expanding A plurality of wings 25 are formed between the pressing members 33 so as to protrude outward in the radial direction of the expansion / contraction part. Specifically, at this time, a part of the expansion / contraction part enters the gap between the pressing surfaces 33a, 33b (specifically, each wing forming surface) facing each pressing member 33, and the respective surfaces 33a, 33b, Wings 25 are formed by being sandwiched between 33b. More specifically, a part of the expansion / contraction part is sandwiched between these surfaces 33a and 33b for a predetermined time (for example, 30 to 60 seconds), whereby the wing 25 is formed. In this step, the wings 25 may be formed in a state where a mandrel for fixing the inner diameter is inserted into the inner tube hole 29 of the inner tube 16.

  As described above, in the present embodiment, since the balloon crushing diameter D is set to be smaller than the outer diameter of the proximal leg region 13a, the expansion / contraction portion of the balloon 13 is performed by performing the wing formation process. The area | region where the outer diameter is larger than the outer diameter of the proximal side leg area | region 13a will be pressed by each pressing member 33. Therefore, the entire region (the entire region in the axial direction) of the proximal cone region 13b is pressed by the pressing member 33, whereby the wings 25 can be formed over the entire region 13b. Further, since the balloon crushing diameter D is set to be larger than the outer diameter of the distal leg region 13e, it is possible to avoid the pressing member 33 from biting into the region 13e. Further, since the proximal leg region 13a of the balloon 13 is arranged outside the arrangement region 37, it is possible to avoid the pressing member 33 from biting into the region 13a.

  After the wing formation process is completed, a negative pressure is applied to the balloon 13, and in this state, each pressing member 33 is moved to the initial position to remove the balloon 13 from the arrangement region 37. Thereby, the state where the wings 25 are formed on the balloon 13 is maintained.

  Next, a folding step of folding the wings 25 along the circumferential direction of the balloon 13 is performed. Hereinafter, this process will be described with reference to FIG. In this step, the wing 25 is folded using the folding device 40 shown in FIG. The folding device 40 has substantially the same basic configuration as the wing forming device 30 described above, and is set on the center side of the opening 42 in a plan view of the base plate 41 having the opening 42 and the plate 41. And a plurality of folding members 43 surrounding the arrangement region 47 of the balloon 13. Each of these folding members 43 is pivotally supported via a pivot shaft 45 disposed at the opening edge of the opening 42 in the base plate 41.

  In the folding step, first, as shown in FIG. 7 (b), the balloon 13 is placed in the placement region 47 of the folding device 40, and then the folding member 43 is rotated as shown in FIG. 7 (c). The wings 25 are folded while the wings 25 are pushed to the rotating side by the member 43. Thereby, each wing 25 is folded in the radial direction of the balloon 13 and is wound around the axis of the balloon 13.

  Next, a shaping process is performed in which the balloon 13 is heated by covering the outer side of the balloon 13 with the wings 25 folded and the balloon 13 is heated. In this case, for example, the balloon 13 is heated at 70 ° C. for 20 minutes.

  Thereafter, as a post process, a process of attaching the hub 12 to the proximal end portion of the catheter tube 11 is performed, and a series of manufacturing operations is completed.

  Next, a method for using the balloon catheter 10 will be briefly described.

  First, a guide wire G is inserted into the inner tube hole 29 of the balloon catheter 10 (inner tube 16), and the inserted guide wire G is inserted into the blood vessel in advance. It is inserted into the blood vessel through an introducer). At this time, the guide wire G is introduced to the distal side of the stenosis in the blood vessel. Subsequently, the balloon catheter 10 is inserted into the blood vessel while performing a push-pull operation along the guide wire G, and the balloon 13 is placed at the stenosis. At this time, the balloon 13 is kept in a contracted state. Thereafter, a compressed fluid is supplied to the balloon 13 from the hub 12 side through the outer tube hole 21 of the outer tube 15 using a pressurizer, and the balloon 13 is inflated. As a result, the narrowed portion is expanded by the balloon 13.

  After the expansion of the narrowed portion is completed, the balloon 13 is deflated by discharging the compressed fluid in the balloon 13 (applying a negative pressure to the balloon 13). Then, in the contracted state, the balloon 13 is extracted from the blood vessel through a sheath introducer or the like. Here, as described above, when the balloon 13 is in the contracted state, the wings 25 are formed in the entire region of the proximal cone region 13b, so that the folding performance of the wings 25 in the proximal cone region 13b is enhanced. Therefore, the re-wrapping (rewinding) performance of the proximal cone region 13b, which is likely to become resistance when the balloon 13 is pulled out from the sheath introducer or the like, is enhanced, thereby reducing the pull-out resistance when the balloon 13 is pulled out. ing. Therefore, in this case, the operation of pulling out the balloon 13 from the body can be facilitated.

  The balloon catheter 10 is mainly passed through a blood vessel as described above and used for treating blood vessels such as coronary arteries, femoral arteries, and pulmonary arteries. It can also be applied to “tubes” and “body cavities”.

  Next, the magnitude of the pulling force when pulling out the balloon 13 having the above configuration from the sheath introducer will be described in comparison with a balloon manufactured by a conventional manufacturing method (hereinafter referred to as a conventional balloon). Here, a balloon 13 having an axial length (total length) of 40 mm and a straight tube region 13c having an outer diameter of 8 mm is used, and a sheath introducer having an inner diameter of 2.14 to 2.27 mm is used. To do. Further, in the balloon 13 of the present embodiment, the balloon crushing diameter D is set to 1.24 mm and the wings 25 are formed. However, in the conventional balloon, the balloon crushing diameter D is 1.5 mm (that is, the proximal leg region 13a). The wings 25 are formed with the same diameter as the outer diameter.

  In measuring the pulling force, the balloon 13 is first inserted into the sheath introducer in a deflated state. Thereafter, the balloon 13 is inflated by applying a nominal pressure to the balloon 13. Here, 0.8 MPa is assumed as the nominal pressure. Thereafter, the balloon 13 is deflated again, and the balloon 13 is withdrawn proximally from the sheath introducer. Then, the pulling force F (in other words, pulling resistance) at the time of pulling is measured. The pulling force F is measured three times for each of the balloon 13 of the present embodiment and the conventional balloon.

  FIG. 8 shows the measurement results obtained by measuring the pulling force of the balloon 13. As shown in the figure, in the conventional balloon, the measured value of the pulling force F was 5.0, 5.7, and 5.7 N, and the average value was 5.5 N. On the other hand, in the balloon 13 of the present embodiment, the measured values of the pulling force F were 3.6, 5.3, and 4.3N, and the average value was 4.4N. That is, in the balloon 13 of the present embodiment, the pulling force F is smaller than that of the conventional balloon, in other words, the pulling resistance is reduced. This is because, in the balloon 13 of the present embodiment, since the wings 25 are formed over the entire region of the proximal cone region 13b as described above, the wings 25 are sufficiently folded in the region 13b. It can be said that the rewrap performance (rewinding property) is thereby improved.

  As mentioned above, according to the structure of this embodiment explained in full detail, the following outstanding effects are acquired.

  In the proximal joining step, the outer tube 15 is inserted into the proximal leg region 13a so that the distal end thereof is located in the middle of the proximal leg region 13a, and the proximal leg region 13a is inserted in the inserted state. And the outer tube 15 are joined to form a non-joined region 28 that is not joined to the outer tube 15 in a part of the distal side of the proximal leg region 13a. Thereby, in the wing formation process, when the balloon 13 is crushed by the pressing member 33, the non-joining region 28 is deformed such as to be stretched, so that it is joined to the outer tube 15 in the proximal leg region 13 a. It is possible to suppress a tensile force from acting on the region (joining region). Therefore, the inconvenience that the proximal leg region 13a is detached from the outer tube 15 due to the pulling force can be suppressed.

  Further, in the above-described configuration using the rotating type that moves inward in the radial direction of the balloon 13 by rotating as the pressing member 33, when the balloon 13 is crushed by the pressing member 33, It is assumed that a force in the outer peripheral direction is applied to the outer peripheral surface by the member 33. In that case, it is considered that the pulling force acting on the proximal leg region 13a is increased, and the above-described inconvenience is likely to occur. In that respect, in such a configuration, the non-joining region 28 is provided in a part of the proximal leg region 13a, so that the above-described inconvenience can be suitably suppressed.

  Furthermore, since each pressing member 33 is moved to a position where the diameter of the virtual inscribed circle X inscribed in the non-opposing pressing surface 33c of each pressing member 33 is larger than the outer diameter of the distal leg region 13e, Compared with the case where each pressing member 33 is moved to a position where the diameter of the inscribed circle X is smaller than the outer diameter of the distal leg region 13e, the tensile force acting on the proximal leg region 13a can be suppressed. Therefore, the effect which suppresses the said inconvenience also in this point can be expected.

  The present invention is not limited to the above embodiment, and may be implemented as follows, for example.

  (1) The wing forming apparatus 30 used in the wing forming process is not limited to the one in the above embodiment. For example, the pressing member 33 of the device 30 may be capable of linearly moving in the radial direction of the balloon 13 instead of a rotary type. An example is shown in FIG. In FIG. 9, a plurality of (four in FIG. 9) pressing members 51 are arranged so as to surround the periphery of the balloon 13 (expansion / contraction part). These pressing members 51 are movable in the radial direction of the balloon 13, that is, in the direction toward the central axis of the balloon 13, and are configured to crush the balloon 13 by moving inward in the radial direction. The pressing member 51 has a pressing surface 51a that presses the outer peripheral surface of the balloon 13 toward the radially inner side of the balloon 13, and a pair of wing forming surfaces 51b formed on both sides of the pressing surface 51a. The pressing surface 51 a has a concave arc shape, and the wing forming surface 51 b is a facing surface facing the wing forming surface 51 b of the other pressing member 51. That is, the adjacent pressing members 51 are arranged in a state where the respective wing forming surfaces 51b face each other with a predetermined interval (interval for wing formation). Therefore, in the above embodiment, the “pressing surface (non-opposing pressing surface 33c) for pressing the expansion / contraction portion radially inward” and the “wing forming surface” on the same surface (specifically, the first pressing surface 33a). Whereas both are formed, in the present example, these surfaces are individually formed as different surfaces.

  In such a configuration, when each pressing member 51 is moved from the initial position shown in FIG. 9A to the wing formation position shown in FIG. 9B, the expansion and contraction portion of the balloon 13 is brought radially inward by the pressing surface 51a. As a result of being crushed, a part of the expansion / contraction part protrudes between the wing forming surfaces 51b of the pressing members 51 and is sandwiched between the surfaces 51b. Thereby, the wings 25 can be formed on the balloon 13 even in such a configuration.

  (2) In the above embodiment, the balloon crushing diameter D of the pressing member 33 is larger than the outer diameter of the distal leg region 13e, but this is changed to be smaller than the outer diameter of the distal leg region 13e. May be. If it does so, the wing | blade 25 can be formed over the whole region in the distal side cone area | region 13d of the balloon 13, and the wing | blade 25 can be formed over the whole region of an expansion-contraction part by extension. Therefore, the folding performance of the wing 25 can be improved not only in the proximal cone region 13b but also in the distal cone region 13d, and the pulling resistance when the balloon 13 is pulled out from the body can be further reduced.

  Further, in such a configuration, the length dimension of the pressing member 33 (specifically, the non-opposing pressing surface 33 c) in the central axis A <b> 1 direction of the arrangement region 37 is the same as the axial length of the expansion / contraction part of the balloon 13. In addition, in the balloon placement step, it is desirable to place the balloon 13 in the placement region 37 in a state where both ends of the expansion / contraction part are aligned with both ends of the pressing member 33, respectively. Then, it is possible to avoid the pressing member 33 from biting into the distal leg region 13e in the wing formation step, and thus the wing 25 is spread over the entire expansion / contraction part while preventing damage to the distal leg region 13e. Can be formed.

  (3) In the above embodiment, in the balloon placement step, the boundary between the proximal leg region 13a and the proximal cone region 13b (hereinafter referred to as the proximal cone / leg boundary) is a pressing member 33 (non-opposing). The balloon 13 is arranged in the arrangement region 37 so as to be in the same position as the end of the pressing surface 33c), but this is changed so that the proximal cone-leg boundary is closer to the end of the pressing member 33. The balloon 13 may be arranged so as to be positioned on the distal side. Even in this case, it is possible to avoid the pressing member 33 from biting into the proximal leg region 13a, so that the region 13a can be prevented from being crushed or damaged as in the above embodiment. Further, in this case, the balloon 13 is disposed so that the end of the pressing member 33 (non-opposing pressing surface 33c) is located in the range from the center in the axial direction to the proximal end in the proximal cone region 13b. Is preferred. Then, the wings 25 can be formed in the above-mentioned range where the wall thickness is relatively large at the expansion / contraction part of the balloon 13, which is effective in reducing the pull-out resistance of the balloon 13.

  Further, the balloon 13 may be arranged such that the proximal cone-leg boundary portion is located on the distal side of the end portion of the pressing member 33 (in other words, located within the range of the pressing member 33). In this case, since the proximal cone region 13b can be reliably pressed by the pressing member 33 until reaching the proximal cone / leg boundary, the formation of the wings 25 in the region 13b can be performed more suitably. . However, from the viewpoint of preventing the pressing member 33 from biting into the proximal leg region 13a, the balloon 13 is placed at the proximal cone leg boundary portion with the end of the pressing member 33 or close to it. It is desirable to arrange so that it is located on the side of the back.

  (4) In the above embodiment, the outer tube 15 is inserted into the proximal leg region 13 a of the balloon 13, and both the members 13 a and 15 are joined. You may join both these 13a and 15 in the state which inserted the area | region 13a. In this case, if both 13a and 15 are joined in a state where only a part of the proximal leg region 13a on the proximal side is inserted into the outer tube 15, the outer tube 15 is joined to a part of the proximal leg region 13a. A non-bonded region can be provided.

  DESCRIPTION OF SYMBOLS 10 ... Balloon catheter, 13 ... Balloon, 13a ... Proximal leg area | region, 13b ... Proximal cone area | region, 15 ... Outer tube, 16 ... Inner tube, 25 ... Wing, 28 ... Non-joining area | region, 33 ... Pressing member.

Claims (5)

A fluid tube having a fluid lumen for circulating the fluid;
The fluid lumen includes a proximal joint joined to the distal end side of the tube, and a proximal enlarged portion expanded from the distal end of the joint toward the distal side. A balloon having an expansion / contraction portion that expands or contracts by fluid flowing through
In a method for producing a balloon catheter comprising:
An inflating step of inflating the balloon;
The inflating / shrinking portion inflated in the balloon is moved by moving a plurality of pressing members arranged around the inflating / shrinking portion radially inward of the inflating / shrinking portion to a predetermined position and crushed by each of the pressing members. A wing forming step of forming a plurality of wings by projecting a part of the contraction portion toward the radially outer side between the pressing members,
When the predetermined position is assumed to be a virtual inscribed circle that is inscribed in a pressing surface that presses the expansion / contraction portion inward in the radial direction in each pressing member, the diameter of the virtual inscribed circle is the proximal side joint portion Is set to a position smaller than the outer diameter of
The method for producing a balloon catheter, wherein the plurality of wings are formed in the inflating and deflating portion in a deflated state of the balloon and folded along a circumferential direction of the balloon. Prior to the wing formation step, comprising a placement step of placing the balloon in a balloon placement region which is an inner region surrounded by the plurality of pressing members,
In the arrangement step, the balloon is placed in the axial direction so that the boundary between the proximal joint and the expansion / contraction part is placed at the same position as the end of the pressing surface of the pressing member or closer to the proximal side. Placed so that
The balloon catheter manufacturing method according to claim 1, wherein in the wing formation step, the expansion / contraction portion of the balloon arranged in the arrangement step is crushed by the pressing members. Before the expansion step, further comprising a joining step of joining the proximal joint and the fluid tube;
In the joining step, the proximal joint and the fluid tube are joined so that a part of the distal side of the proximal joint is a non-joined region that is not joined to the fluid tube. The method for producing a balloon catheter according to claim 1 or 2.   2. The pressing member according to claim 1, wherein the pressing member is provided so as to be rotatable about a rotation shaft extending in the same direction as the axial direction of the balloon, and moves inward in the radial direction of the balloon by the rotation. 4. The method for producing a balloon catheter according to any one of 3 above. An inner shaft that is inserted inside the fluid tube in a state in which a part extends to the distal side of the tube;
The balloon is applied to a balloon catheter including a distal side joint portion that is joined to the extended extension portion of the inner shaft and has a smaller outer diameter than the proximal side joint portion,
The predetermined position is set to a position where the diameter of the virtual inscribed circle is smaller than the outer diameter of the proximal joint and larger than the outer diameter of the distal joint. The manufacturing method of the balloon catheter as described in any one of Claims 1 thru | or 4.

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