JP2018121944A - Manufacturing method of stent delivery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a stent delivery system which can increase capability of retaining a stent on a balloon and can obtain high passage properties into a lumen of a living body.SOLUTION: A manufacturing method of a stent delivery system 10 including a balloon 30 whose diameter can be enlarged, a shaft part 20 where the balloon 30 is attached, and a stent 70 which is mounted on an outer peripheral surface of the balloon 30 and is equipped with a linear strut 71 that forms a tubular outer periphery where a gap 72 is formed, includes an attaching process for attaching the balloon 30 to the shaft part 20, an arranging process for arranging the stent 70 in a position where the stent 70 is mounted on the balloon 30 in a diameter-reduced state, a transfer process for transferring a groove 35 corresponding to a shape of the stent 70 on an outer surface of the balloon 30 by applying a pressure on the inside of the balloon 30 while limiting the increase in a diameter of the stent 70, a fitting process for fitting the stent 70 in the groove 35 of the balloon 30, and a diameter reduction process for reducing the diameter of the stent 70.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method for manufacturing a stent delivery system.

  In recent years, for example, in the treatment of acute myocardial infarction or angina pectoris, a method of placing a stent in a lesion (stenosis) of a coronary artery has been performed, and other blood vessels, bile ducts, trachea, esophagus, urethra, and other biological ducts A similar method may be used to improve a lesion formed in a cavity. A stent delivery system used for placement of a stent generally includes a long shaft portion, a balloon that is provided on the distal end side of the shaft portion and is radially expandable, and a stent that is attached to the outer peripheral surface of the balloon. When the balloon is expanded after reaching the target site in the body, the stent attached to the balloon expands while being plastically deformed, and the lesioned part is expanded. Thereafter, when the balloon is deflated, the stent is left in an expanded state, and the state where the lesion is pushed and expanded is maintained.

  In a stent delivery system, when a stent is mounted on a balloon, the outer diameter (profile) of the distal portion of the catheter is increased, which may reduce the passage through a living body lumen. Use of a stent delivery system that is difficult to pass through the lesion is undesirable because it increases the operation time and the burden on the patient.

  In addition, when the stent is not mounted on the balloon with sufficient holding force, the stent may fall off the balloon before the stent is delivered to the lesion. For this reason, it is preferable that the stent is mounted on the balloon with a sufficient holding force.

  The balloon catheter described in Patent Document 1 includes a balloon having at least one circumferential groove. A circumferential groove is a circumferentially extending groove adjacent to the transition between the intermediate body of the balloon and the tapered end. The circumferential groove can function as a site for holding the stent on the balloon when the balloon is deflated.

  In addition, the balloon catheter described in Patent Document 2 includes a balloon having at least one hinge point. The hinge point is provided on the main body wall of the balloon so as to surround the longitudinal axis of the balloon. This hinge point can increase the flexibility in the longitudinal direction of the balloon and improve the retention of the stent against the balloon.

JP 2005-525138 A JP-T-2005-502428

  However, in the balloon catheter described in Patent Document 1, the outer diameter of the tapered end portion is larger than the outer diameter of the intermediate body. For this reason, the outer diameter difference between a taper-shaped edge part and an intermediate body will arise, and there exists a possibility of impairing the passage property of a balloon catheter. Moreover, although the groove | channel extended in the circumferential direction can control the movement of the axial direction of a stent, since the movement of the circumferential direction of a stent cannot be controlled, the position of a stent may shift | deviate to the circumferential direction.

  Further, in order to manufacture the balloon catheter described in Patent Document 2, a grinding process and a laser processing process for forming a hinge point on the balloon are newly required. As a result, the manufacturing cost may increase. Furthermore, the stent cannot be securely fitted to the unevenness of the hinge point, and the stent may fall off the balloon.

  The present invention has been made to solve the above-described problems, and provides a stent delivery system capable of improving the ability to hold a stent on a balloon and obtaining high passage through a living body lumen. It aims to provide a method.

  A manufacturing method of a stent delivery system that achieves the above object includes a balloon capable of expanding diameter, a shaft portion to which the balloon is attached, and a wire that is attached to the outer peripheral surface of the balloon and forms a cylindrical outer periphery with a gap formed therein. A stent delivery system comprising a stent having a strut-like strut, an attachment step of attaching the balloon to the shaft portion, and a position of the stent in a reduced diameter state where the stent is attached. Alternatively, the placement step of arranging a cylindrical mold having a shape corresponding to the stent on the inner peripheral surface, and applying pressure to the inside of the balloon while restricting the diameter expansion of the stent or the cylindrical mold, the stent Alternatively, a transfer step of transferring a groove corresponding to the shape of the cylindrical mold to the outer surface of the balloon; and It has a fitting step of fitting to the groove of over emissions, and a reduced diameter step of diameter of the stent.

  In the manufacturing method of the stent delivery system configured as described above, a groove corresponding to the shape of the stent or the cylindrical mold is transferred to the balloon, and the stent is fitted into the groove. To increase. As a result, the ability of the balloon to hold the stent is improved, the outer diameter of the distal portion of the stent delivery system is reduced, and high passage through the living body lumen is obtained.

  In the method of manufacturing the stent delivery system, in the arranging step, the stent is arranged at a position where the stent is mounted on the balloon, and an outer periphery of the stent is covered with a cylinder. A groove corresponding to the shape of the stent may be transferred to the outer surface of the balloon by applying pressure to the inside of the balloon while restricting the diameter expansion of the stent. Thereby, the diameter expansion of a stent can be favorably restrict | limited by the cylinder which covers a stent. For this reason, the protrusion part and groove | channel corresponding to the shape of a stent with high precision can be transcribe | transferred to the outer surface of a balloon using an actual stent.

  In the method of manufacturing the stent delivery system, in the placement step, a position where the stent is to be mounted is covered with the tubular mold, and in the transfer step, the diameter of the tubular mold is limited while the balloon is being expanded. A groove corresponding to the shape of the inner peripheral surface of the cylindrical mold may be transferred to the outer surface of the balloon by applying pressure to the inside of the balloon. As a result, the protruding portion and the groove corresponding to the shape of the stent can be transferred to the outer surface of the balloon without using the actual stent by the cylindrical mold having the inner peripheral surface corresponding to the stent. Therefore, by disposing only the cylindrical mold on the balloon, the protruding portion and the groove can be formed on the outer surface of the balloon, and the workability in manufacturing the stent delivery system is improved.

  In the method of manufacturing the stent delivery system, in the fitting step, the cylindrical mold is removed from the balloon, the stent is disposed on the outer surface of the balloon, and the stent is rotated relative to the balloon. The struts may be fitted in the grooves. Thereby, by rotating the stent, the strut can be easily positioned and fitted in the groove of the balloon.

  The manufacturing method of the stent delivery system may heat the balloon while applying pressure to the inside of the balloon in the transfer step. As a result, the balloon is easily deformed, and it is easy to allow the balloon to enter the gap of the stent or the concave portion of the inner peripheral surface of the cylindrical mold.

  In the method for manufacturing the stent delivery system, the balloon may be heated to a temperature below the crystallization temperature of the balloon in the transfer step. Thereby, while becoming easy to deform | transform a balloon, it suppresses that a balloon deteriorates by heating, and can maintain the intensity | strength of a balloon favorable.

  In the manufacturing method of the stent delivery system, the balloon may be heated to a temperature higher than a glass transition temperature of the balloon in the transfer step. As a result, the balloon is easily deformed, and the balloon can easily enter the gap between the stents.

It is a top view of a stent delivery system. FIG. 6 is a cross-sectional view of the distal portion of the stent delivery system before the balloon is expanded. FIG. 6 is a longitudinal cross-sectional view of the distal portion of the stent delivery system before the balloon is expanded. It is a longitudinal cross-sectional view of the distal part of the stent delivery system which expanded the balloon. 1 is a schematic perspective view showing an apparatus for crimping a stent. FIG. It is a top view for demonstrating the manufacturing method of the stent delivery system which concerns on 1st Embodiment, (A) is the state which has arrange | positioned the stent to a balloon, (B) is the state which covered the balloon and the stent with the cylinder, ( C) shows a state in which the shape of the stent is transferred to the balloon, and (D) shows a state in which the diameter of the stent is reduced. It is sectional drawing which shows the state which formed the protrusion part and the groove | channel on the balloon using the stent and the cylinder. It is sectional drawing which shows the state which formed the protrusion part and the groove | channel on the balloon using the cylindrical type | mold. It is a top view for demonstrating the manufacturing method of the stent delivery system which concerns on 2nd Embodiment, (A) is the state which prepared the cylindrical type | mold, (B) is the state which covered the cylindrical type | mold on the balloon, (C ) Shows a state in which the shape of the cylindrical mold is transferred to the balloon, (D) shows a state in which struts are fitted in the grooves of the balloon, and (E) shows a state in which the diameter of the stent is reduced.

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.
<First Embodiment>

  A stent delivery system 10 manufactured by the method for manufacturing a stent delivery system according to the first embodiment includes a stenosis (or occlusion) generated in a blood vessel, bile duct, trachea, esophagus, urethra, or other living body lumen. A device for expanding and securing a lumen. In this specification, the side to be inserted into the lumen is referred to as “distal side”, and the proximal side to be operated is referred to as “proximal side”.

  As shown in FIGS. 1 to 3, the stent delivery system 10 includes a long shaft portion 20, a balloon 30 provided at a distal portion of the shaft portion 20, a stent 70 attached to the balloon 30, and the shaft portion 20. And a hub 40 fixed to the proximal end of the.

The shaft portion 20 includes an outer tube 50 that is a tubular body and an inner tube 60 that is a tubular body disposed inside the outer tube 50. The outer tube 50 has an expansion lumen 51 in which an expansion fluid for expanding the balloon 30 flows. The inner tube 60 has a guide wire lumen 61 into which a guide wire is inserted. The expansion fluid may be gas or liquid, and examples thereof include gas such as helium gas, CO ₂ gas, and O ₂ gas, and liquid such as physiological saline and contrast medium.

  A flexible tip 64 is connected to the distal portion of the inner tube 60 in order to reduce the burden on the living body due to contact. The inner tube 60 penetrates through the inside of the balloon 30 and opens at a distal opening 62 on the distal side of the balloon 30. The proximal portion of the inner tube 60 penetrates the side wall of the outer tube 50 and opens at the proximal opening 63, and is fixed to the outer tube 50 in a liquid-tight manner by an adhesive or heat fusion. The lumen from the distal opening 62 to the proximal opening 63 is a guide wire lumen 61.

  The hub 40 includes a hub opening 41 that communicates with the expansion lumen 51 of the outer tube 50. The hub opening 41 functions as a port through which the expansion fluid flows in and out. In the hub 40, the proximal portion of the outer tube 50 is fixed in a liquid-tight manner.

  The constituent materials of the outer tube 50, the inner tube 60, and the tip 64 are preferably flexible to some extent. Examples of such a material include resin materials, for example, polyolefins such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more of these, Examples thereof include soft polyvinyl chloride resin, polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, fluororesin and other thermoplastic resins, silicone rubber, latex rubber, and the like.

  Examples of the constituent material of the hub 40 include thermoplastic resins such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer.

  The balloon 30 is a part that expands the living body lumen and the stent 70 by expanding. As shown in FIG. 4 showing the balloon 30 when it is expanded, the balloon 30 has a cylindrical portion 31 having a substantially cylindrical shape and substantially the same diameter at the central portion in the axial direction. The cylindrical part 31 can efficiently expand a predetermined range. In addition, the axis orthogonal cross section of the cylindrical part 31 does not necessarily need to be circular. On the distal side of the tubular portion 31 of the balloon 30, a tip tapered portion 32 whose diameter decreases in a tapered shape toward the distal side is provided. On the proximal side of the cylindrical portion 31 of the balloon 30, a proximal tapered portion 33 whose diameter decreases in a tapered shape toward the proximal side is provided.

The distal side of the tip tapered portion 32 is liquid-tightly fixed to the outer wall surface of the inner tube 60 with an adhesive or heat fusion. The proximal side of the proximal end taper portion 33 is liquid-tightly fixed to the outer wall surface of the proximal portion of the outer tube 50 by an adhesive or heat fusion. Therefore, the inside of the balloon 30 communicates with the expansion lumen 51 formed in the outer tube 50. In the balloon 30, the expansion fluid can flow in from the proximal side via the expansion lumen 51. The balloon 30 is expanded by the inflow of the expansion fluid, and is folded and contracted by the discharge of the inflowing expansion fluid.

  As shown in FIGS. 2 and 3, the balloon 30 is positioned between a protrusion 34 that protrudes radially outward from a gap 72 formed between struts 71 that are wire rods constituting the stent 70, and the protrusion 34. Groove 35 is provided. The balloon 30 is shaped in a state in which the balloon 30 is folded around the outer peripheral surface of the inner tube 60 in a circumferential direction before being expanded. Such a balloon 30 can be formed by blow molding in which a parison portion of a tube as a raw material is heated in a mold, inflated with a gas such as nitrogen from the inside, and pressed against the mold. The balloon may be in a form that is not folded, but is deformed so as to be elastically stretched and the outer diameter is widened.

  The balloon 30 is preferably formed of a material having a certain degree of flexibility. Such materials include engineering plastics, for example, polyolefins such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more of these, Examples thereof include soft polyvinyl chloride resin, polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, fluororesin and other thermoplastic resins, silicone rubber, latex rubber, and the like.

  The stent 70 is a so-called balloon expandable stent that expands by plastic deformation due to the expansion force of the balloon 30. The stent 70 is mounted (mounted) on the cylindrical portion 31 of the balloon 30. The material constituting the stent 70 is preferably a biocompatible metal or resin. Examples of the metal having biocompatibility include iron base alloys such as stainless steel, tantalum (tantalum alloy), platinum (platinum alloy), gold (gold alloy), cobalt chrome alloys such as cobalt chromium alloy, titanium alloys, and niobium alloys. Etc. In addition to this, the biocompatible metal is preferably a biodegradable metal material, and examples thereof include magnesium. The biocompatible resin is preferably a biodegradable polymer material such as polylactic acid, polyglycolic acid, lactic acid-glycolic acid copolymer, polycaprolactone, lactic acid-caprolactone copolymer, and poly-γ-glutamic acid. Examples include degradable synthetic polymer materials, and biodegradable natural polymer materials such as cellulose and collagen.

  The stent 70 is preferably a drug-eluting stent, and a drug layer that contains the drug and elutes the drug in vivo is preferably provided on the outer surface of the stent 70. The stent 70 may not be a drug eluting stent.

  The stent 70 has a linear strut 71. The strut 71 forms a cylindrical outer periphery with a gap 72. As shown in FIG. 4, the stent 70 can be deformed and expanded in diameter so that the gap 72 between the struts 71 is expanded by expanding the balloon 30.

  The strut 71 of the stent 70 in the contracted state is fitted in the groove 35 of the balloon 30 as shown in FIGS. The protruding portion 34 of the balloon 30 enters the gap 72 of each stent 70 in the contracted state from the inner peripheral surface side of the stent 70. The protrusion 34 protrudes from the inner peripheral surface side of the stent 70 to the outer peripheral surface side through the gap 72. Each protrusion 34 preferably protrudes further outward than the outer peripheral surface of the stent 70, but is not limited thereto. Accordingly, there may be both a protrusion 34 that protrudes outward from the outer peripheral surface of the stent 70 and a protrusion 34 that does not protrude outward from the outer peripheral surface of the stent 70. The protrusion 34 has a shape corresponding to the shape of the gap 72.

  Next, a manufacturing apparatus 100 for manufacturing the stent delivery system 10 will be described. As shown in FIG. 5, the manufacturing apparatus 100 includes a fixing unit 110 that attaches the stent 70 to the balloon 30, a gas supply unit 120 that supplies fluid to the balloon 30 via the expansion lumen 51, the balloon 30, and the stent 70. And a heating unit 140 for heating the balloon 30.

  The fixing unit 110 may be a general crimping machine used for mounting the stent 70 on the balloon 30 of the stent delivery system 10. The fixed part 110 includes a plurality of movable members 112 arranged in the circumferential direction so as to form a chamber 111 whose inner diameter can be reduced. The inner diameter of the chamber 111 can be expanded and contracted by relatively moving the plurality of movable members 112.

  The gas supply unit 120 is, for example, a syringe, an indeflator, or a pump. The gas supply unit 120 is connected to the hub opening 41 and supplies gas to the balloon 30 through the expansion lumen 51 or discharges the gas from the balloon 30.

  The cylindrical body 130 can cover the outer side of the stent 70 that covers the deflated balloon 30. The tubular body 130 is a tubular body that restricts the diameter expansion of the stent 70 that receives a force from the expanding balloon 30. Therefore, the cylindrical body 130 has a strength that hardly deforms even when an expansion force is received from the accommodated balloon 30. The inner diameter of the cylinder 130 is larger than the outer diameter of the deflated balloon 30. The inner diameter of the cylindrical body 130 is preferably as small as possible within a range in which the stent 70 before being attached to the balloon 30 can be accommodated. Accordingly, when the balloon 30 is expanded, the diameter of the stent 70 outside the balloon 30 is suppressed by the cylindrical body 130, so that the balloon 30 can be bitten into the gap 72 of the stent 70. Therefore, it is preferable that the inner diameter of the cylindrical body 130 is a size that can suppress expansion of the stent 70 before being attached to the balloon 30 only by elastic deformation without plastic deformation.

  The constituent material of the cylinder 130 preferably has a certain degree of strength, and for example, a resin material or a metal material can be applied. Examples of the resin material include resin materials such as polyolefins such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more of these, and soft poly Examples thereof include thermoplastic resins such as vinyl chloride resin, polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane, and fluorine resin, polycarbonate, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer. Examples of the metal material include stainless steel, cobalt chrome, nickel titanium, and the like.

  The heating unit 140 heats the balloon 30 to a temperature at which it is easy to deform. The heating unit 140 is, for example, a heater including a heating wire. The heating temperature of the heating unit 140 exceeds room temperature, and is preferably near or above the glass transition temperature of the material of the balloon 30. In this case, the balloon 30 is easily deformed, and the balloon 30 is easily placed in the gap 72 of the stent 70. When the glass transition temperature has a temperature range, the temperature above the glass transition temperature includes the entire range of the glass transition temperature. If the heating temperature of the heating unit 140 is close to the glass transition temperature, the balloon 30 can be sufficiently deformed even if it is somewhat lower than the glass transition temperature. The heating temperature of the heating unit 140 is preferably equal to or lower than the crystallization temperature of the material of the balloon 30. Thereby, it can suppress that the balloon 30 deteriorates by heating, and can maintain the intensity | strength of the balloon 30 favorable. The heating unit 140 may heat the gas supplied to the balloon 30. In this case, the heating unit 140 can heat the balloon 30 through the gas. The heating unit may be incorporated in a cylinder that covers the balloon 30 and the stent 70.

  Next, a method for manufacturing the stent delivery system 10 according to the first embodiment will be described.

  First, the balloon 30 and the hub 40 are attached to the shaft portion 20 (attachment process). Next, as shown in FIG. 6A, the stent 70 before being expanded is disposed so as to surround the tubular portion 31 of the deflated balloon 30. Note that the stent 70 in this state can be further reduced in diameter in a later step in order to be attached to the balloon 30. Next, as shown in FIG. 6 (B), the cylindrical body 130 is disposed so as to surround the cylindrical portion 31 and the stent 70 (arrangement step). Thereafter, the balloon 30 is heated by the heating unit 140 (see FIG. 5). The balloon 30 is preferably heated near the glass transition temperature or above the glass transition temperature and below the crystallization temperature. As a result, the balloon 30 can be deformed flexibly and strength deterioration is suppressed. The heating of the balloon 30 may be performed before the stent 70 is disposed on the balloon 30 or may be performed after the stent 70 is disposed on the balloon 30 and before the cylindrical body 130 is disposed. Good.

  Next, gas is supplied to the inside of the balloon 30 through the expansion lumen 51 by the gas supply unit 120 (see FIG. 5). Thereby, the internal pressure in the balloon 30 rises, and as shown in FIG. 7, the stent 70 is elastically deformed and adheres closely to the inner peripheral surface of the cylindrical body 130. Note that the stent 70 may not be deformed. Further, the balloon 30 that has been heated and easily deformed enters the gap 72 of the stent 70 and adheres to the inner peripheral surface of the cylindrical body 130. Thereby, the shape of the strut 71 of the stent 70 is transferred to the outer surface of the balloon 30, and the protrusion 34 and the groove 35 are formed (transfer process). Thereafter, when the temperature of the balloon 30 is lowered, the projecting portion 34 and the groove 35 of the balloon 30 are held in a shaped state. At this time, the stent 70 is fitted in the groove 35 of the balloon 30 (fitting process). The balloon 30 is heated near the glass transition temperature or above the glass transition temperature and below the crystallization temperature, and then falls below the glass transition temperature, so that the shape of the protrusion 34 and the groove 35 is changed to the original shape (protrusion). The shape before the portion 34 and the groove 35 are formed is not completely restored, and the protruding portion 34 and the groove 35 are maintained well.

  Next, the gas is discharged from the balloon 30 by the gas supply unit 120 (see FIG. 5). The stent 70 is maintained on the outer surface of the deflated balloon 30. At this time, the stent 70 is fitted in the groove 35 of the balloon 30. Thereafter, as shown in FIG. 6C, the cylindrical body 130 covering the balloon 30 and the stent 70 is removed. In FIG. 6C, the stent 70 is shown through.

  Next, the balloon 30 and the stent 70 are inserted into the chamber 111 of the manufacturing apparatus 100 (see FIG. 5). Next, the movable member 112 is moved to reduce the inner diameter of the chamber 111. Thereby, the stent 70 is plastically deformed to reduce the diameter, and is firmly attached to the outer surface of the balloon 30 (a diameter reduction process).

  Next, the movable member 112 is moved to expand the inner diameter of the chamber 111. At this time, the protruding portion 34 of the balloon 30 protrudes radially outward from the gap 72 of the stent 70. Thereafter, the stent delivery system 10 is taken out from the fixing portion 110. Thereby, as shown in FIGS. 2, 3, and 6 (D), the manufacture of the stent delivery system 10 is completed.

  As described above, the manufacturing method of the stent delivery system 10 according to the first embodiment includes the balloon 30 that can be expanded in diameter, the shaft portion 20 to which the balloon 30 is attached, the outer peripheral surface of the balloon 30, and the gap 72. A stent 70 having a linear strut 71 that forms a formed cylindrical outer periphery, and a manufacturing method of a stent delivery system 10 comprising: an attachment step of attaching a balloon 30 to a shaft portion 20; The placement step of placing the stent 70 at the position where the stent 70 of the balloon 30 is mounted, and the groove 35 corresponding to the shape of the stent 70 by applying pressure to the inside of the balloon 30 while restricting the diameter expansion of the stent 70 A transfer step for transferring to the outer surface of 30 and a fitting step for fitting the stent 70 into the groove 35 of the balloon 30 Has a reduced diameter step of diameter of the stent 70. In the manufacturing method configured as described above, the groove 35 corresponding to the shape of the stent 70 is transferred to the balloon 30, and the stent 70 is fitted into the groove 35. Therefore, the volume of the balloon 30 entering the gap 72 of the stent 70 is reduced. As the number of the balloons 30 increases, the balloon 30 comes into close contact with the stent 70. For this reason, the ability of the balloon 30 to hold the stent 70 is improved, and the safety of the stent 70 is improved by preventing the stent 70 from falling off the balloon 30 and catching the stent 70 on the living body. Further, the volume of the balloon 30 that enters the gap 72 of the stent 70 increases, so that the volume of the balloon 30 positioned on the radially inner side of the stent 70 decreases. For this reason, the outer diameter of the distal portion of the stent delivery system 10 is reduced, and the permeability to the living body lumen is improved. By improving the passability, the operation time can be shortened, the burden on the patient can be reduced, and dropping of the drug layer on the outer surface of the balloon 30 can be suppressed.

  In addition, in the method of manufacturing the stent delivery system 10, the stent 70 is arranged at a position where the stent 70 of the balloon 30 is mounted in the arrangement step, and the outer periphery of the stent 70 is covered with a cylinder. The groove 35 corresponding to the shape of the stent 70 can be transferred to the outer surface of the balloon 30 by applying pressure to the inside of the balloon 30 while restricting the diameter expansion of the 70. Thereby, the diameter expansion of the stent 70 can be favorably limited by the cylindrical body 130 covering the stent 70. For this reason, the protrusion 34 and the groove 35 corresponding to the shape of the stent 70 with high accuracy can be transferred to the outer surface of the balloon 30 using the actual stent 70.

  Moreover, the manufacturing method of the stent delivery system 10 can heat the balloon 30 while applying pressure to the inside of the balloon 30 in the transfer step. Accordingly, the balloon 30 is easily deformed, and the balloon 30 can be easily inserted into the gap 72 of the stent 70.

  Moreover, the manufacturing method of the stent delivery system 10 can heat the balloon 30 below the crystallization temperature of the said balloon 30 in a transcription | transfer process. Thereby, the balloon 30 is easily deformed, the balloon 30 is prevented from being deteriorated by heating, and the strength of the balloon 30 can be maintained well.

Moreover, the manufacturing method of the stent delivery system 10 can heat the balloon 30 to near the glass transition temperature of the balloon 30 or higher than the glass transition temperature in the transfer step. Accordingly, the balloon 30 is easily deformed, and the balloon 30 can be easily inserted into the gap 72 of the stent 70.
Second Embodiment

  The manufacturing method of the stent delivery system 10 according to the second embodiment is different from the manufacturing method according to the first embodiment in that the stent 70 is not used when forming the protrusion 34 and the groove 35 in the balloon 30. In addition, the same code | symbol is attached | subjected to the site | part which has a function similar to 1st Embodiment, and description is abbreviate | omitted.

  In the second embodiment, as shown in FIGS. 8 and 9 (A), when forming the protrusion 34 and the groove 35 in the balloon 30, the cylindrical mold 150 is used instead of the stent 70 and the cylindrical body 130.

  The cylindrical mold 150 can cover the deflated balloon 30. The cylindrical mold 150 includes a convex portion 151 having a shape corresponding to the strut 71 of the stent 70 attached to the balloon 30 and a concave portion 152 having a shape corresponding to the gap 72 on the inner peripheral surface. The cylindrical mold 150 has a strength that hardly deforms even when an expansion force is received from the accommodated balloon 30. Therefore, as will be described in detail later, when the balloon 30 is expanded, the groove 35 corresponding to the shape of the cylindrical mold 150 is formed by applying pressure to the inside of the balloon 30 while restricting the diameter expansion of the cylindrical mold 150. It can be transferred to the outer surface of the balloon 30. The inner diameter of the cylindrical mold 150 is larger than the outer diameter of the deflated balloon 30. The material applicable to the cylindrical body of the first embodiment can be applied as the constituent material of the cylindrical mold 150.

  Next, a method for manufacturing the stent delivery system 10 according to the second embodiment will be described.

  First, the balloon 30 and the hub 40 are attached to the shaft portion 20 (attachment process). Next, as shown in FIG. 9B, the cylindrical mold 150 is disposed so as to surround the cylindrical portion 31 (arrangement step). Thereafter, the balloon 30 is heated by the heating unit 140 (see FIG. 5). The balloon 30 is preferably heated to near the glass transition temperature and above the glass transition temperature and below the crystallization temperature. As a result, the balloon 30 can be deformed flexibly and strength deterioration is suppressed. The heating of the balloon 30 may be performed before the cylindrical mold 150 is disposed outside the balloon 30. The heating unit may be incorporated in the cylindrical mold 150.

  Next, gas is supplied to the inside of the balloon 30 through the expansion lumen 51 by the gas supply unit 120 (see FIG. 5). As a result, the internal pressure in the balloon 30 increases, and the diameter of the balloon 30 is increased as shown in FIG. Then, the balloon 30 that has been heated and easily deformed enters the concave portion 152 of the cylindrical mold 150 and comes into close contact with the inner peripheral surface of the cylindrical mold 150. Thereby, the shape of the concave part 152 and the convex part 151 of the cylindrical mold 150 is transferred to the outer surface of the balloon 30 to form the protruding part 34 and the groove 35 (transfer process). Thereafter, when the temperature of the balloon 30 is lowered, the projecting portion 34 and the groove 35 are held in a shaped state. The balloon 30 is heated near the glass transition temperature and above the glass transition temperature and below the crystallization temperature, and then falls below the glass transition temperature, so that the shapes of the protrusions 34 and the grooves 35 become the original shapes (protrusions). The shape before the portion 34 and the groove 35 are formed is not completely restored, and the protruding portion 34 and the groove 35 are maintained well.

  Next, gas is discharged from the balloon 30 by the gas supply unit 120. As a result, the balloon 30 is deflated, and the protruding portion 34 of the balloon 30 comes out of the concave portion 152 of the cylindrical mold 150. At this stage, a part of the protrusion 34 may remain in the recess 152. Thereafter, as shown in FIG. 9C, the cylindrical mold 150 covering the balloon 30 is removed from the balloon 30.

  Next, as illustrated in FIG. 9D, the stent 70 before being expanded is disposed so as to surround the tubular portion 31 of the deflated balloon 30. Note that the stent 70 in this state can be further reduced in diameter in a later step in order to be attached to the balloon 30. Thereafter, the balloon 30 or the stent 70 is rotated. When the position of the strut 71 overlaps the position of the groove 35 of the balloon 30, the strut 71 is fitted into the groove 35 (fitting process). By rotating the balloon 30 or the stent 70, it is easy to align and fit the strut 71 to the groove 35 of the balloon 30. Note that the strut 71 may not reach the bottom of the groove 35 in the state of being fitted in the groove 35. The relative rotation direction of the stent 70 with respect to the balloon 30 is preferably the winding direction of the balloon 30 with respect to the shaft portion 20 (the clockwise direction in FIGS. 2 and 8). Thereby, when the stent 70 rotates with respect to the balloon 30, it can suppress that winding of the balloon 30 with respect to the shaft part 20 can be released.

  Next, the balloon 30 and the stent 70 are inserted into the chamber 111 of the manufacturing apparatus 100 (see FIG. 5). Next, the movable member 112 is moved to reduce the inner diameter of the chamber 111. Thereby, the stent 70 is plastically deformed to reduce the diameter, and is firmly attached to the outer surface of the balloon 30 (a diameter reduction process).

  Next, the movable member 112 is moved to expand the inner diameter of the chamber 111. At this time, the protruding portion 34 of the balloon 30 protrudes radially outward from the gap 72 of the stent 70. Thereafter, the stent delivery system 10 is taken out from the fixing portion 110. Thereby, as shown in FIGS. 2, 3, and 9 (E), the manufacture of the stent delivery system 10 is completed.

  As described above, the manufacturing method of the stent delivery system 10 according to the second embodiment includes the balloon 30 that can be expanded in diameter, the shaft portion 20 to which the balloon 30 is attached, the outer peripheral surface of the balloon 30, and the gap 72. A stent 70 having a linear strut 71 that forms a formed cylindrical outer periphery, and a manufacturing method of a stent delivery system 10 comprising: an attachment step of attaching a balloon 30 to a shaft portion 20; An arrangement step of arranging a cylindrical die 150 having a shape corresponding to the stent 70 on the inner peripheral surface at a position where the stent 70 of the balloon 30 is mounted, and the inside of the balloon 30 while restricting the diameter expansion of the cylindrical die 150 A transfer step of transferring the groove 35 corresponding to the shape of the cylindrical mold 150 to the outer surface of the balloon 30 by applying pressure to the stent 70; It has a fitting step of fitting the groove 35 of the balloon 30, the reduced diameter step of diameter of the stent 70. In the manufacturing method configured as described above, the groove 35 corresponding to the shape of the cylindrical mold 150 is transferred to the balloon 30, and the stent 70 is fitted into the groove 35. As the volume increases, the balloon 30 comes into close contact with the stent 70. For this reason, the ability of the balloon 30 to hold the stent 70 is improved, and the safety of the stent 70 is improved by preventing the stent 70 from falling off the balloon 30 and catching the stent 70 on the living body. Further, the volume of the balloon 30 that enters the gap 72 of the stent 70 increases, so that the volume of the balloon 30 positioned on the radially inner side of the stent 70 decreases. For this reason, the outer diameter of the distal portion of the stent delivery system 10 is reduced, and the permeability to the living body lumen is improved. By improving the passability, the operation time can be shortened, the burden on the patient can be reduced, and dropping of the drug layer on the outer surface of the balloon 30 can be suppressed.

  In addition, the manufacturing method of the stent delivery system 10 covers the balloon 30 with the cylindrical mold 150 at the placement step, where the stent 70 is mounted, and limits the diameter expansion of the cylindrical die 150 in the transfer step. The groove 35 corresponding to the shape of the cylindrical mold 150 can be transferred to the outer surface of the balloon 30 by applying pressure to the inside. As a result, the cylindrical die 150 having an inner peripheral surface corresponding to the shape of the stent 70 allows the protrusion 34 and the groove 35 corresponding to the shape of the stent 70 to be formed on the balloon 30 without using the actual stent 70. Can be transferred to the outer surface. Therefore, by disposing only the cylindrical mold 150 on the balloon 30, the protruding portion 34 and the groove 35 can be formed on the outer surface of the balloon 30, and the workability in manufacturing the stent delivery system 10 is improved.

  Further, in the manufacturing method of the stent delivery system 10, in the fitting step, the cylindrical mold 150 is removed from the balloon 30, the stent 70 is disposed on the outer surface of the balloon 30, and the stent 70 is rotated relative to the balloon 30. Thus, the strut 71 can be fitted into the groove 35. Thus, by rotating the stent 70, the strut 71 can be easily aligned and fitted in the groove 35 of the balloon 30.

  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 cylindrical portion of the balloon may not have a constant outer diameter.

  Further, the structure of the stent is not particularly limited as long as a gap is provided in which a part of the balloon can enter while being attached to the balloon.

  A test was conducted to measure the force holding the balloon stent. The test was conducted according to EN ISO 25539-2 and ASTM F2394-07. The test was conducted in water at 37 ° C. using blood vessel models (ASTM F2394-07 FIG. X2.2 and FIG. X2.3). As the stent delivery system, Ultimatemaster (registered trademark) 4028 manufactured by Terumo Corporation was used. The constituent material of the balloon had a nylon layer and a nylon elastomer layer.

  Examples were produced by the manufacturing method shown in the first embodiment described above. That is, in order to transfer the protrusion and the groove to the balloon, a stent and a cylindrical body covering the stent were used. The heating temperature of the balloon when transferring the protrusion and the groove to the balloon was 50 ° C. After removing the cylindrical body from the balloon and the stent, the diameter of the stent fitted into the groove of the balloon was reduced by a crimping machine to produce a stent delivery system.

  The comparative example was tested using a stent delivery system in which a stent was attached to a balloon with a crimping machine without using a cylinder or a cylindrical mold. The dimensions and constituent materials of the balloon and stent in the comparative example were the same as those in the example. As a result, it was confirmed that the holding strength of the example was 20% higher than the holding strength of the comparative example.

DESCRIPTION OF SYMBOLS 10 Stent delivery system 20 Shaft part 30 Balloon 34 Projection part 35 Groove 70 Stent 71 Strut 72 Gap 100 Manufacturing apparatus 130 Cylindrical body 140 Heating part 150 Cylindrical type 151 Convex part 152 Concave part

Claims (7)

A stent delivery comprising: a balloon capable of expanding diameter; a shaft portion to which the balloon is attached; and a stent having a linear strut that is attached to the outer peripheral surface of the balloon and forms a cylindrical outer periphery with a gap formed therein. A method of manufacturing a system,
An attachment step of attaching the balloon to the shaft portion;
An arrangement step of arranging a cylindrical mold having an inner peripheral surface with a shape corresponding to the stent or the stent at a position where the stent of the balloon in a reduced diameter state is mounted;
A transfer step of transferring a groove corresponding to the shape of the stent or the cylindrical mold to the outer surface of the balloon by applying pressure to the inside of the balloon while limiting the diameter expansion of the stent or the cylindrical mold;
A fitting step of fitting the stent into the groove of the balloon;
A method for manufacturing a stent delivery system, comprising: a diameter reducing step for reducing the diameter of the stent. In the arranging step, the stent is arranged at a position where the stent of the balloon is mounted, and the outer periphery of the stent is covered with a cylindrical body,
In the transfer step, a groove corresponding to the shape of the stent is transferred to the outer surface of the balloon by applying pressure to the inside of the balloon while restricting the diameter expansion of the stent by the cylindrical body. The manufacturing method of the stent delivery system of description. In the placing step, the cylindrical mold is put on a position where the stent of the balloon is mounted,
In the transfer step, the groove corresponding to the shape of the cylindrical mold is transferred to the outer surface of the balloon by applying pressure to the inside of the balloon while restricting the diameter expansion of the cylindrical mold. The manufacturing method of the stent delivery system of description.   In the fitting step, the tubular mold is removed from the balloon, the stent is disposed on the outer surface of the balloon, the stent is rotated relative to the balloon, and the strut is fitted into the groove. The manufacturing method of the stent delivery system of Claim 3 combined.   The manufacturing method of the stent delivery system according to any one of claims 1 to 4, wherein in the transfer step, the balloon is heated while applying pressure to the inside of the balloon.   The method for manufacturing a stent delivery system according to claim 5, wherein, in the transfer step, the balloon is heated to a temperature equal to or lower than a crystallization temperature of the balloon.   The stent delivery system manufacturing method according to claim 5 or 6, wherein, in the transfer step, the balloon is heated to a temperature equal to or higher than a glass transition point of the balloon.

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