JP2016182312A - Balloon catheter and manufacturing method of balloon catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a balloon catheter that achieves both high expansion force and high passage property, and a manufacturing method of the balloon catheter.SOLUTION: A balloon catheter includes a catheter shaft 11 having a hollow outer tube 20 and an inner tube 21 disposed in the hollow interior of the outer tube 20, and a balloon 12 fixed to the tip of the catheter shaft 11. The balloon 12 is formed of a proximal end side balloon member 30 and a distal end side balloon member 31. The base end side of the proximal end side balloon member 30 is fixed to the tip of the outer tube 20. The tip side of the distal end side balloon member 31 is fixed to the tip of the inner tube 21, and a base end side thereof is fixed to the proximal end side balloon member 30. The distal end side balloon member 31 is formed of a material having higher compliance property than the proximal end side balloon member 30.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a balloon catheter having a balloon at a distal end portion of a catheter shaft and a method for manufacturing the same.

  Treatment of vascular lesions using a catheter is widely performed because of less surgical invasion. For example, in percutaneous transluminal coronary angioplasty, a balloon catheter is used to expand the coronary lesion and improve blood flow. The balloon catheter generally has a long hollow catheter shaft, a balloon provided on the distal end side of the catheter shaft, and a hub provided on the proximal end side of the catheter shaft.

  The balloon of the balloon catheter needs to have high flexibility in order to be inserted into a bent biological lumen. Also, it is desirable that the flexibility is high in order to improve the passage through the narrowed portion. However, a material having high flexibility generally has high compliance. Compliance refers to the rate of elongation in the radial direction with respect to the expansion pressure applied to the balloon. A balloon having a relatively high compliance is called a semi-compliance balloon. Since such a balloon is made of a highly flexible material, when the expansion pressure is increased, the soft portion of the stenosis may be overexpanded and the expected therapeutic effect may not be obtained. is there.

  On the other hand, a balloon formed of a material having high rigidity has low compliance. Therefore, such a balloon is difficult to cause overexpansion when the expansion pressure is increased. However, balloons with low compliance are less flexible. A balloon having relatively low compliance is called a low compliance balloon.

  On the other hand, for example, Patent Document 1 discloses a balloon having moderate compliance and flexibility.

JP 2001-29450 A

  As in Patent Document 1, by adjusting the blending ratio of the polymer material forming the balloon, a balance between the compliance and flexibility of the balloon can be obtained to some extent. However, even a balloon such as Patent Document 1 has high permeability to a stenosis (flexibility based on a material with high compliance), and high expansion force (low compliance) that is difficult to cause overexpansion above a predetermined expansion pressure. Since the rigidity based on the material is a contradictory property, it is difficult to achieve two properties with one material.

  The present invention has been made in order to solve the above-described problems, and has a balloon catheter that achieves both high permeability to a stenosis and the like and high expansion force that is difficult to cause overexpansion at a predetermined expansion pressure or higher, and its manufacture. It aims to provide a method.

  A balloon catheter according to the present invention that achieves the above object includes a catheter shaft having a hollow outer tube, an inner tube disposed inside the hollow of the outer tube, and a balloon fixed to a distal end portion of the catheter shaft. The balloon is formed by a proximal balloon member and a distal balloon member, and the proximal balloon member is fixed at the distal end of the outer tube at the proximal end, and the distal balloon The member has a distal end side fixed to the distal end portion of the inner tube and a proximal end side fixed to the proximal end side balloon member, and the distal end side balloon member has higher compliance than the proximal end side balloon member. Formed by the material.

  The balloon catheter manufacturing method according to the present invention also includes a catheter shaft having a hollow outer tube and an inner tube disposed inside the hollow of the outer tube, and a balloon fixed to the distal end portion of the catheter shaft. A balloon catheter manufacturing method comprising: a proximal balloon member that forms a proximal end side of the balloon; and a distal end side of the balloon that has higher compliance than the proximal balloon member. A step of preparing a distal end side balloon member formed of a material having, a step of forming the balloon by joining a proximal end side of the distal end side balloon member to the proximal end side balloon member, and the proximal end Fixing the proximal end side of the side balloon member to the distal end portion of the outer tube, and fixing the distal end side of the distal end side balloon member to the distal end portion of the inner tube.

  In the balloon catheter configured as described above, the balloon is formed by the proximal balloon member and the distal balloon member. Since the distal side balloon member has higher compliance than the proximal side balloon member, the distal side balloon member has high flexibility on the distal end side and can improve the passage of the balloon. Further, since the proximal balloon member has lower compliance than the distal balloon member, the balloon proximal end side has high rigidity, can suppress overexpansion, and can secure expansion force. That is, according to the present invention, the balloon catheter can have both a high expansion force and a high passability.

  The proximal balloon member has an inner overlapping portion fixed to the inner surface of the distal balloon member on the distal end side, and the distal balloon member is fixed to the outer surface of the proximal balloon member on the proximal end side. If the outer overlapping portion is provided, the proximal balloon member and the distal balloon member can be easily overlapped and joined together.

  In the expanded state, the balloon continues to the expansion effective portion, the proximal end tapered portion that is continuous with the proximal end of the expansion effective portion and decreases in diameter toward the proximal end, and the distal end of the expansion effective portion. If it has a tip side taper portion whose diameter decreases toward the tip side, and the inner overlap portion and the outer overlap portion are overlapped and joined only within the range of the expansion effective portion, distortion or the like occurs. The balloon can be expanded without any problem, and the lesion can be reliably expanded.

  If both the inner overlapping portion and the outer overlapping portion have substantially the same length as the expansion effective portion in the axial direction and overlap each other, the entire expansion effective portion, The distal end side balloon member is overlapped, and a step or the like is not generated in the dilation effective portion, so that it is possible to eliminate the influence on treatment due to the balloon being formed of two members.

  Of the distal balloon member and the proximal balloon member, if a lubricant is provided on the surface of only the distal balloon, the friction of the portion on the distal end side of the balloon during insertion into the living body lumen The force can be reduced and the passage of the balloon can be further improved.

  According to the above-described balloon catheter manufacturing method, it is possible to manufacture a balloon catheter having a balloon that achieves both high expansion force and high passability.

  In the step of forming the balloon, the outer overlapping portion of the distal balloon member is overlapped from the outer surface of the inner overlapping portion of the proximal balloon member, and the two are joined to form the balloon. In this way, the proximal balloon member and the distal balloon member can be easily overlapped and joined together.

  If a step of providing a lubricant on the surface of the tip side balloon member is formed before forming the balloon, a balloon having higher passability can be manufactured.

  After providing a lubricant on the surface of the tip side balloon member, a step of applying crosslinking heat to the tip side balloon member is performed, and a step of forming the balloon is performed after the step of applying the crosslinking heat. For example, since the crosslinking heat is applied only to the distal balloon member, and the crosslinking heat is not applied to the proximal balloon member formed of the low compliance material, the expansion force of the balloon is not reduced. Further, since the lubricant is thermally cross-linked on the surface of the distal end side balloon member, durability on the surface of the distal end side balloon member is improved. Therefore, the tip side balloon member can maintain high lubricity, so that a balloon with higher passability can be manufactured.

  If the distal balloon member and the proximal balloon member are formed by blowing a parison into a balloon shape and then cutting a part of the balloon shape, the distal balloon member and the proximal balloon member are formed. The balloon member can be easily formed.

It is a front view of the balloon catheter in this embodiment. It is sectional drawing of tip part vicinity of a balloon catheter. It is sectional drawing showing the process of providing a lubrication agent in a front end side balloon member. It is sectional drawing showing the process of joining a base end side balloon member and a front end side balloon member. It is sectional drawing showing the process of joining a balloon to a catheter shaft.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio. Further, in this specification, the side of the balloon catheter 10 that is inserted into the living body lumen is referred to as “tip” or “tip side”, and the proximal side for operation is referred to as “base end” or “base end side”.

  First, the configuration of the balloon catheter 10 will be described. As shown in FIG. 1, the balloon catheter 10 is fixed to a long and hollow catheter shaft 11, a balloon 12 provided at the distal end of the catheter shaft 11, and a proximal end of the catheter shaft 11. And a hub 13.

  This balloon catheter 10 allows a long catheter shaft 11 to be inserted into a living organ and a balloon 12 provided on the distal side of the balloon catheter 10 is expanded at the lesioned part to expand and spread the lesioned part. it can. The catheter shaft 11 is provided with an opening 11a into which the guide wire 14 is introduced near the distal end side. That is, the balloon catheter 10 is a so-called rapid exchange type catheter.

  Next, the structure of the distal end portion of the catheter shaft 11 and the balloon 12 will be described. As shown in FIG. 2, the catheter shaft 11 has a hollow outer tube 20 and an inner tube 21 that is a hollow inner support. The inner tube 21 is housed in the hollow interior of the outer tube 20, and the catheter shaft 11 has a double tube structure at the tip. The hollow interior of the inner tube 21 forms a guide wire lumen 23 through which the guide wire 14 is inserted. Further, an expansion lumen 22 through which the expansion fluid of the balloon 12 is circulated is formed inside the hollow of the outer tube 20 and outside the inner tube 21.

The inner tube 21 protrudes further to the distal end side than the distal end of the outer tube 20. The balloon 12 has a proximal end portion fixed to the distal end portion of the outer tube 20 and a distal end portion fixed to the distal end portion of the inner tube 21. Thereby, the inside of the balloon 12 communicates with the expansion lumen 22. The balloon 12 can be expanded by injecting an expansion fluid into the balloon 12 via the expansion lumen 22. The expansion fluid may be a gas or a liquid. For example, a gas such as helium gas, CO ₂ gas, or O ₂ gas, or a liquid such as physiological saline or contrast medium can be used. In FIG. 2, the balloon 12 is in an expanded state.

  The outer tube 20 and the inner tube 21 are preferably formed of a material having a certain degree of flexibility. Examples of such a material include polyolefins such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more thereof, soft polyvinyl chloride resin, Examples thereof include fluororesins such as polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, polytetrafluoroethylene, silicone rubber, and latex rubber.

  In the expanded state, the balloon 12 has an expansion effective portion 12b that pushes a lesioned portion such as a stenosis portion, and a proximal-side tapered portion that is continuous with the proximal end of the expansion effective portion 12b and decreases in diameter toward the proximal end. 12a and a distal end side taper portion 12c which is continuous with the distal end of the expansion effective portion and decreases in diameter toward the distal end side. In addition, it is preferable that the expansion effective part 12b has the substantially same outer diameter along an axial direction in the state which the balloon 12 expanded. The balloon 12 is formed by joining and integrating the proximal balloon member 30 and the distal balloon member 31 with each other.

  The proximal-side balloon member 30 includes an outer tube fixing portion 30a that is fixed to the distal end portion of the outer tube 20, and a proximal-side taper portion forming portion 30b that is formed on the distal side from the outer tube fixing portion 30a. And an inner overlapping portion 30c formed on the distal end side with respect to the proximal side taper portion forming portion 30c. The distal side balloon member 31 includes an inner tube fixing portion 31a fixed to the distal end side end portion of the inner tube 21, and a distal end side taper portion forming portion 31b formed proximal to the inner tube fixing portion 31a. And an outer overlapping portion 31c formed on the base end side from the distal end side taper portion forming portion 31b.

  The inner overlapping portion 30 c of the proximal balloon member 30 is fixed and integrated with the inner surface of the outer overlapping portion 31 c of the distal balloon member 31. Further, the inner overlapping portion 30c of the proximal balloon member 30 and the outer overlapping portion 31c of the distal balloon member 31 both have the axial length of the expansion effective portion 12b of the balloon 12, and the balloon 12 is effectively expanded. It overlaps only in the range of the part 12b.

  For this reason, on the outer surface of the balloon 12, the proximal-side tapered portion 12 a is formed by the proximal-side balloon member 30, and the expansion effective portion 12 b and the distal-side tapered portion 12 c are formed by the distal-side balloon member 31. The Further, on the inner surface of the balloon 12, the proximal end side tapered portion 12 a and the expansion effective portion 12 b are formed by the proximal end side balloon member 30, and the distal end side tapered portion 12 c is formed by the distal end side balloon member 31. .

  Note that X-ray contrast markers indicating both end portions of the expansion effective portion 12b may be provided in portions located at both ends of the expansion effective portion 12b in the inner tube 21. Thereby, when delivering the balloon 12 to a lesioned part, the surgeon can accurately grasp the position of the effective expansion part 12b having the maximum outer diameter when the balloon 12 is expanded.

  The distal end side balloon member 31 is formed of a material having higher compliance than the proximal end side balloon member 30. The compliance is defined by the rate of change of the balloon diameter in a predetermined internal pressure range applied to the balloon 12. Here, the characteristic that the change rate of the balloon diameter is 2 to 7% when the internal pressure is in the range of 6 to 12 atmospheres is low compliant, and the change rate of the balloon diameter is 7 to 16% in the same internal pressure range. Is semi-compliant. The proximal balloon member 30 is made of a low-compliant material, and the distal balloon member 31 is made of a semi-compliant material.

  The compliance can be adjusted by the blending ratio of each material when using a material blended with materials having different flexibility. Moreover, when using the material which laminated | stacked the material which has a different softness | flexibility, compliance can be adjusted with the ratio of the thickness of each material.

  The material of the proximal balloon member 30 and the distal balloon member 31 is a polyolefin such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more of these. Alternatively, soft polyvinyl chloride resin, polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, polytetrafluoroethylene, or other fluororesin can be used.

  Further, a lubricant is provided on the outer surface of the distal end side balloon member 31. The lubricant is provided to improve the passage of the balloon 12 by reducing friction in the living body lumen. As the lubricant, the following wet lubricating polymers can be used. The wet lubricating polymer is a high molecular weight material having wettability in vivo, such as polyvinyl pyrrolidone, maleic anhydride-based polymers such as maleic anhydride methyl vinyl ether copolymer, N, N-dimethylacrylamide polymer, N , N-dimethylacrylamide and other copolymerizable monomers such as acrylamide polymers, (meth) acrylate polymers containing amide group-containing monomers such as N, N-dimethylaminoethyl acrylate in the main chain, polyvinyl Polymers having polyethylene glycol chains such as alcohol and polyethylene glycol, water-soluble polyamides such as nylon P-70, and modification containing a monomer having a phospholipid such as methacryloyloxyethyl phosphorylcholine (MPC) in the side chain (meta ) Modification of acrylic polymers Polymers, sulfonic acid-modified polymers, polysaccharides such as chitosan, cellulose derivatives such as hydroxypropyl cellulose, glycogen derivatives, alginic acid, mucin, natural product derived chondroitin etc., and the like. Note that the proximal balloon member 30 is not provided with a lubricant.

  As described above, the balloon 12 is inserted into the living body lumen by joining the low-compliance proximal balloon member 30 and the highly-compliant distal balloon member 31 and integrating them to form the balloon 12. In this case, the flexibility of the distal end side is high, so that the passage of the balloon 12 can be improved. In addition, since the balloon 12 has higher rigidity on the proximal end side than at least a part of the effective expansion portion 12b and the effective expansion portion 12b, it is possible to suppress overexpansion and secure expansion force. In particular, the proximal end side balloon member 30 and the distal end side balloon member 31 are overlapped over the entire length of the effective expansion portion 12b, and the both are expanded only by overlapping the effective expansion portion 12b. It is possible to prevent the balloon 12 from being distorted. Further, since the distal side balloon member 31 forms the outer surface side of the expansion effective portion 12b, the distal end side tapered portion 12c that forms the distal end side of the balloon 12 by providing a lubricant to the distal end side balloon member 31. From the expansion effective portion 12b, the lubricant can be present on the outer surface.

  Next, a method for manufacturing the balloon 12 will be described. Since the balloon 12 is formed by the proximal balloon member 30 and the distal balloon member 31 as described above, first, these are prepared. The proximal balloon member 30 and the distal balloon member 31 are each molded into a normal balloon shape having a proximal tapered portion, an expansion effective portion, and a distal tapered portion using a mold or the like, By cutting in the direction orthogonal to the axial direction at the portion of the extended effective portion, it can be manufactured into a predetermined shape.

  Specifically, by inserting a pipe (parison) formed of a thermoplastic resin made of the material of the proximal end side balloon member 30 into a mold and blow molding, the proximal end side tapered portion, the expansion effective portion, and the distal end Let it be a molded balloon having a side taper. This balloon has the shape of a normal balloon. And it can manufacture in the predetermined shape of the base end side balloon member 30 by cut | disconnecting in the direction orthogonal to an axial direction with a cutting tool in the part of an expansion effective part.

  Similarly, the distal end side balloon member 31 is formed by inserting a pipe (parison) formed of a thermoplastic resin made of the material of the distal end side balloon member 31 into a die or the like and blow-molding the proximal end side tapered member. A normal balloon shape having a portion, an expansion effective portion, and a distal end side tapered portion is formed. And it can manufacture in a predetermined shape by cut | disconnecting in the direction orthogonal to an axial direction in the part of an expansion effective part.

  Next, as shown in FIG. 3, a lubricant layer is provided on the outer surface of the distal end side balloon member 31. For this, a method such as immersion can be used. Further, after providing the lubricant layer, crosslinking heat is applied to the distal end side balloon member 31. Thereby, the durability of the lubricant can be improved. On the other hand, the distal end side balloon member 31 contracts by applying crosslinking heat, and the expansion force decreases by being thermally cured.

  Subsequently, as illustrated in FIG. 4, the inner overlapping portion 30 c of the proximal balloon member 30 and the outer overlapping portion 31 c of the distal balloon member 31 are joined and integrated. By bringing the outer surface of the inner overlapping portion 30c and the inner surface of the outer overlapping portion 31c into contact with each other and joining them, the outer surface of the expansion effective portion 12b can be formed on the distal end side balloon member 31. It is desirable that the bonding be performed with an adhesive. However, if fusion can be performed at a temperature that does not affect the flexibility and the like of each balloon member, they may be joined by heat fusion.

  When the balloon 12 is integrated, as shown in FIG. 5, the outer tube fixing portion 30a of the proximal balloon member 30 is fixed to the distal end portion of the outer tube 20, and the inner tube fixing portion 31a of the distal balloon member 31 is fixed. Is fixed to the end of the inner tube 21 on the distal end side. The balloon 12 is fixed by heat fusion. Thereby, the balloon 12 is fixed to the catheter shaft 11.

  According to the method having such a process, the balloon catheter 10 having the balloon 12 having higher flexibility on the distal end side than the distal side taper portion 12c and higher expansion force on the proximal end side than the expansion effective portion 12b is manufactured. be able to. Also, a lubricant is provided only on the distal end side balloon member 31 that forms the outer surfaces of the distal end side tapered portion 12c and the expansion effective portion 12b, and after the application of bridging heat, it is integrated with the proximal end side balloon member 30. Thus, it is possible to prevent crosslinking heat from being applied to the proximal balloon member 30 having low compliance. Although the expansion force of the distal end side balloon member 31 to which crosslinking heat is applied is reduced by contraction and thermosetting, the expansion force of the balloon 12 as a whole is sufficiently ensured by being integrated with the proximal end side balloon member 30. it can. That is, according to this manufacturing method, it is possible to sufficiently ensure the expansion force of the balloon 12 while providing the balloon 12 with a highly durable lubricant.

  As described above, the balloon catheter 10 according to this embodiment includes the catheter shaft 11 having the hollow outer tube 20 and the inner tube 21 disposed inside the hollow of the outer tube 20, and the distal end portion of the catheter shaft 11. The balloon 12 is formed by a proximal balloon member 30 and a distal balloon member 31, and the proximal balloon member 30 has a proximal end on the distal end of the outer tube 20. The distal end side balloon member 31 has a distal end side fixed to the distal end portion of the inner tube 21 and a proximal end side fixed to the proximal end side balloon member 30. The distal end side balloon member 31 is a proximal end side balloon member. It is formed of a material having a compliance higher than 30. Thereby, the balloon 12 is formed by the proximal balloon member 30 and the distal balloon member 31, and the distal balloon member 31 has higher compliance than the proximal balloon member 30. The flexibility is high and the passage of the balloon 12 can be improved. Moreover, since the balloon 12 has high rigidity on the base end side and can suppress overexpansion, an expansion force can be secured. That is, according to the present invention, it is possible to make the balloon catheter 10 compatible with both high expansion force and high passability.

  The proximal balloon member 30 has an inner overlapping portion 30c fixed to the inner surface of the distal balloon member 31 on the distal end side, and the distal balloon member 31 is located on the proximal end side of the proximal balloon member 30. If the outer overlapping portion 31c fixed to the outer surface is provided, the proximal balloon member 30 and the distal balloon member 31 can be easily overlapped and joined together.

  In the expanded state, the balloon 12 has an expanded effective portion, a proximal-side tapered portion that is continuous with the proximal end of the expanded effective portion and decreases in diameter toward the proximal end, and a distal end of the expanded effective portion. If it has a tip side taper portion that is continuous and has a diameter that decreases toward the tip side, and the inner overlapping portion 30c and the outer overlapping portion 31c are overlapped and joined only within the range of the expansion effective portion 12b, distortion, etc. The balloon 12 can be expanded without causing it to occur, and the lesion can be reliably expanded.

  In addition, if both the inner overlapping portion 30c and the outer overlapping portion 31c have substantially the same length as the extension effective portion 12b in the axial direction and overlap each other, the entire extension effective portion 12b can be The balloon member 30 and the front-end side balloon member 31 overlap each other, so that no step or the like is generated in the dilation effective portion 12b, and the influence on the treatment due to the balloon 12 being formed of two members can be eliminated. it can.

  In addition, if a lubricant is provided on only the distal side balloon 31 of the distal side balloon member 31 and the proximal side balloon member 30, the distal side of the balloon 12 is inserted into the living body lumen. The frictional force of the portion can be reduced and the passage of the balloon 12 can be further improved.

  The balloon catheter manufacturing method according to the present embodiment is fixed to a catheter shaft 11 having a hollow outer tube 20 and an inner tube 21 arranged inside the hollow of the outer tube 20, and a distal end portion of the catheter shaft 11. A balloon catheter 10 having a balloon 12, which is a base end side balloon member 30 that forms the base end side of the balloon 12, and a tip end side of the balloon 12 that is higher than the base end side balloon member 30. A step of preparing a distal end side balloon member 31 formed of a material having compliance, and a step of forming the balloon 12 by joining the proximal end side of the distal end side balloon member 31 to the proximal end side balloon member 30; The proximal end side of the proximal end side balloon member 30 is fixed to the distal end portion of the outer tube 20, and the distal end side of the distal end side balloon member 31 is fixed to the distal end portion of the inner tube 21. And a step of, a. Thereby, the balloon catheter 10 which has the balloon 12 which made high expansion force and high passage property compatible can be manufactured.

  Further, in the step of forming the balloon 12, the outer overlapping portion 31c included in the distal end side balloon member 31 is overlapped from the outer surface of the inner overlapping portion 30c included in the proximal end side balloon member 30, and the two are joined to each other. 12, the proximal balloon member 30 and the distal balloon member 31 can be easily overlapped and joined together.

  Further, if a step of providing a lubricant on the surface of the tip side balloon member 31 is formed before the balloon 12 is formed, the balloon 12 having higher passability can be manufactured.

  Further, after providing the lubricant on the surface of the distal end side balloon member 31, there is a step of applying crosslinking heat to the distal end side balloon member 31, and a step of forming the balloon 12 is performed after the step of applying crosslinking heat. In this case, crosslinking heat is applied only to the distal balloon member 31 and no crosslinking heat is applied to the proximal balloon member 30 formed of a low-compliance material. Therefore, the balloon 12 can have a sufficient expansion force even if the distal side balloon member 31 is thermally cured by heat treatment. Further, since the coating with the lubricant causes thermal crosslinking on the surface of the distal end side balloon member 31, the durability is improved. Therefore, sufficient lubricity can be maintained during delivery of the balloon 12.

  Further, if the distal side balloon member 31 and the proximal side balloon member 30 are formed by blowing a parison 40 into a balloon shape and then cutting a part of the balloon shape, The proximal balloon member 30 can be easily formed.

  Note that the present invention is not limited to the above-described embodiments, and various modifications can be made by those skilled in the art within the technical idea of the present invention. For example, the catheter according to the above-described embodiment is a rapid exchange type, but may be an over-the-wire type.

  In the above-described embodiment, the balloon 12 is formed by superimposing and joining the inner overlapping portion 30c of the proximal balloon member 30 and the outer overlapping portion 31c of the distal balloon member 31. It is only necessary that the distal end side of 30 and the proximal end side of the distal side balloon member 31 are fixed and integrated with each other, and the fixing structure is not limited to the above.

10 balloon catheter,
11 catheter shaft,
12 Balloon,
12a Base side taper part,
12b Extended effective part,
12c tip side taper part,
13 hub,
14 guide wire,
20 outer tube,
21 Inner pipe,
22 expansion lumen,
23 Guidewire lumen,
30 proximal balloon member,
30a outer tube fixing part,
30b Base end side taper portion forming portion,
30c inner overlapping part,
31 distal end side balloon member,
31a Inner pipe fixing part,
31b Tip side tapered portion forming portion,
31c Outer superposition part.

Claims (10)

A catheter shaft having a hollow outer tube and an inner tube disposed inside the hollow of the outer tube;
A balloon fixed to the distal end portion of the catheter shaft,
The balloon is formed by a proximal balloon member and a distal balloon member,
The proximal balloon member has a proximal end fixed to the distal end of the outer tube,
The distal end side balloon member has a distal end side fixed to the distal end portion of the inner tube, and a proximal end side is fixed to the proximal end side balloon member,
The distal balloon member is a balloon catheter formed of a material having higher compliance than the proximal balloon member. The proximal balloon member has an inner overlapping portion fixed to the inner surface of the distal balloon member on the distal side,
The balloon catheter according to claim 1, wherein the distal balloon member has an outer overlapping portion fixed to an outer surface of the proximal balloon member on a proximal end side. In the expanded state, the balloon continues to the expansion effective portion, the proximal end tapered portion that is continuous with the proximal end of the expansion effective portion and decreases in diameter toward the proximal end, and the distal end of the expansion effective portion. Having a tip side taper portion whose diameter decreases toward the tip side,
The balloon catheter according to claim 2, wherein the inner overlapping portion and the outer overlapping portion are overlapped and joined only in the range of the expansion effective portion.   The balloon catheter according to claim 3, wherein the inner overlapping portion and the outer overlapping portion both have substantially the same length as the dilation effective portion in the axial direction and overlap each other.   The balloon catheter according to any one of claims 1 to 4, wherein a lubricant is provided on a surface of only the distal end side balloon of the distal end side balloon member and the proximal end side balloon member. A catheter shaft having a hollow outer tube and an inner tube disposed inside the hollow of the outer tube;
A balloon fixed to the distal end portion of the catheter shaft, and a balloon catheter manufacturing method comprising:
A proximal balloon member that forms the proximal side of the balloon and a distal balloon member that is formed of a material that forms the distal side of the balloon and has higher compliance than the proximal balloon member are prepared. And a process of
Bonding the proximal end side of the distal end side balloon member to the proximal end side balloon member, thereby forming the balloon;
Fixing the proximal end side of the proximal end side balloon member to the distal end portion of the outer tube, and fixing the distal end side of the distal end side balloon member to the distal end portion of the inner tube;
A method for manufacturing a balloon catheter.   In the step of forming the balloon, the outer overlapping portion of the distal balloon member is overlapped from the outer surface of the inner overlapping portion of the proximal balloon member, and the two are joined to form the balloon. The manufacturing method of the balloon catheter of Claim 6.   The method for manufacturing a balloon catheter according to claim 6 or 7, further comprising a step of providing a lubricant on the surface of the distal-end balloon member before forming the balloon. After providing a lubricant on the surface of the tip side balloon member, the step of applying crosslinking heat to the tip side balloon member,
The method for manufacturing a balloon catheter according to claim 8, wherein a step of forming the balloon is performed after the step of applying the crosslinking heat.   The distal end side balloon member and the proximal end side balloon member are formed by cutting a part of the balloon shape after blow molding a parison into a balloon shape. A method for manufacturing a balloon catheter.

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