JP6528463B2 - CATHETER AND METHOD OF MANUFACTURING THE SAME - Google Patents

Description

  The present invention relates to a catheter used as, for example, a balloon catheter for dilating blood vessels and a method of manufacturing the same.

  In order to treat a stenosis in a blood vessel, it is inserted into a blood vessel, and the balloon is dilated to dilate the stenosis so as to improve the blood flow on the peripheral side of the stenosis, as a balloon catheter for dilation, There are an over-the-wire type balloon catheter and a monorail type balloon catheter.

  In each of these types of balloon catheters, a guide wire is first passed to the intravascular stenosis, and then the balloon catheter is fed to the stenosis along the guidewire to squeeze the balloon by expanding the balloon. Expand the department. At that time, dilation of the constriction part needs to be performed stepwise so as not to damage the blood vessel, and a balloon catheter having a balloon part with a small outer diameter at first is inserted along the guide wire, and the large outer diameter is successively increased. Replace with a balloon catheter with a balloon section.

  In the over-the-wire type balloon catheter, a lumen for a guide wire is formed along the entire length of the catheter tube, and a guide wire is inserted along the lumen, and the balloon portion is narrowed along the guide wire. To guide. Then, after blood vessel dilation with a balloon catheter having a small outer diameter balloon portion is performed, the balloon catheter is replaced with a balloon catheter having an even larger outer diameter balloon portion.

  At that time, since the balloon catheter is withdrawn along the guide wire, the proximal end of the guide wire needs to extend outside the body over the entire length of the catheter tube. Otherwise, the balloon catheter can not be exchanged while leaving the distal end of the guide wire at the stenosis.

  On the other hand, in the monorail type balloon catheter, an opening as a guide wire insertion port is formed in the middle of the catheter tube, and the balloon from the opening through the guide wire insertion lumen (wire lumen) I'm leading to the end. Therefore, in this type of balloon catheter, the length of the guide wire extending outside of the body for exchanging the balloon catheter may be slightly longer than the length corresponding to the length from the opening to the balloon distal end. Compared to the over-the-wire type, it can be shortened and has excellent operability.

  As a monorail type balloon catheter, what is indicated by patent documents 1 or patent documents 2 grade is known, for example.

  In order to manufacture this type of balloon catheter, for example, the proximal end of the inner tube is heat-sealed between the proximal end of the distal outer tube and the distal end of the proximal outer tube A method has been proposed.

  However, in the balloon catheter manufactured by the conventional method, the thin side wall formed only of the material constituting the inner tube is made longitudinally in the fusion-bonded portion for forming the opening of the wire lumen in the middle of the catheter tube. Formed along. As a result, the thin side wall may be torn apart by, for example, the guide wire being rubbed against the thin side wall, and the guidewire may be stuck (stacked) in the torn portion. In that case, the operation of the catheter along the guide wire may be difficult.

JP 2000-217923 A JP 2004-350901

  The present invention has been made in view of such circumstances, and an object thereof is a monorail type catheter, which is a catheter having a small possibility of the guide wire being stuck near the opening of a wire lumen formed in the middle of the catheter tube and its manufacture It is to provide a method.

In order to achieve the above purpose
The method for producing a catheter according to the present invention is
Providing a distal outer tube and a proximal outer tube, each having a main lumen axially formed therein;
Providing an inner tube in which the wire lumen is formed along the axial direction;
Placing the inner tube inside the main lumen of the distal outer tube;
The proximal end of the inner tube is ejected from the proximal end of the distal outer tube and positioned around the distal end of the proximal outer tube such that the respective main lumens communicate The distal end of the proximal outer tube partially overlaps the proximal end of the distal outer tube, and the proximal end of the inner tube and the proximal end of the distal outer tube Fusion bonding with the distal end of the lateral outer tube;
A predetermined ablation length in a distal direction from a predetermined position of the wire lumen proximal opening after fusion in communication with the wire lumen of the inner tube located on the outer periphery of the distal end of the proximal outer tube Cutting a portion of the outer periphery of the inner tube after fusion so that a portion of the wire lumen is exposed to the outside.

  According to the method of manufacturing a catheter of the present invention, from the predetermined position of the wire lumen proximal opening after fusion which communicates with the wire lumen of the inner tube located on the outer periphery of the distal end of the proximal outer tube At a predetermined ablation length in the distal direction, a portion of the outer circumference of the fused inner tube is cut out so that a portion of the wire lumen is exposed to the outside.

  That is, in the present invention, at the fusion-bonded portion for forming the proximal opening of the wire lumen, the thin side wall formed only of the material constituting the inner tube is cut along the axial direction. . Therefore, when using the catheter, the side wall is less likely to be torn and the guide wire is prevented from being stuck (stacked) on the torn side wall. As a result, the operation of the catheter along the guide wire becomes smooth and easy.

  Preferably, a proximal cutting end, which is a start position for cutting out a part of the outer periphery of the inner tube after fusion, is located most distally among the edges of the wire lumen proximal side opening after fusion. It is located between the most distal opening edge position and the most proximal opening edge position located most proximal among the edges of the wire lumen proximal opening after fusion. Preferably, the proximal excision end is closer to the most distal opening edge position than the most recent opening edge position. If the proximal excision end is too proximal to the position described above, there is a risk of cutting off the part where the fusion is incomplete and creating a gap, and as a result, the main lumen is outside through the gap. And there is a risk of leaks in the main lumen.

  Preferably, the distal end of the distal end of the inner tube is fused to the inner circumferential surface of the distal outer tube. Located proximal to the most distal fusion position. Locating the distal resecting end distal to the most distal fusion position may cause a leak in the main lumen.

  The catheter according to the present invention is manufactured by any of the methods described above.

More specifically, the catheter according to the present invention is
An outer tube whose main lumen is formed along the axial direction;
A wire lumen formed internally along the axial direction, and an inner tube extending axially inside the main lumen of the outer tube,
The proximal end of the inner tube is fused to the inner wall of the outer tube midway in the axial direction of the outer tube to form an inner tube fusion portion along the axial direction,
One of the outer peripheries of the inner tube after fusion so that a part of the wire lumen is exposed to the outside at a predetermined cutting length in the distal direction from the wire lumen proximal opening of the inner tube fusion part The department has been cut off.

  In the catheter according to the present invention, the thin side wall formed only of the material constituting the inner tube is cut away along the axial direction. Therefore, when using the catheter, the side wall is less likely to be torn and the guide wire is prevented from being stuck (stacked) on the torn side wall. As a result, the operation of the catheter along the guide wire becomes smooth and easy.

FIG. 1A is a schematic side view of a balloon catheter according to an embodiment of the present invention. FIG. 1B is an enlarged sectional view of an essential part in the vicinity of IB shown in FIG. 1A. FIG. 1C is a partial perspective view of the vicinity of the proximal wire insertion hole of the balloon catheter shown in FIG. 1B. FIG. 1D is a plan view of the vicinity of the proximal wire insertion hole of the balloon catheter shown in FIG. 1C but shows a state before the excision step. FIG. 2A is a cross-sectional view taken along the line IIA-IIA shown in FIG. 1D. FIG. 2B is a cross-sectional view taken along the line IIB-IIB shown in FIG. 1D. FIG. 2C is a cross-sectional view taken along the line IIC-IIC shown in FIG. 1D. FIG. 2D is a cross-sectional view taken along the line IID-IID shown in FIG. 1D. FIG. 2E is a cross-sectional view taken along the line IIE-IIE shown in FIG. 1D. FIG. 2F is a cross-sectional view taken along the line IIF-IIF shown in FIG. 1D. FIG. 2G is a cross-sectional view taken along the line IIG-IIG shown in FIG. 1D. FIG. 2H is a cross-sectional view taken along the line IIH-IIH shown in FIG. 1D. FIG. 2I is a cross-sectional view taken along the line III-III shown in FIG. 1D. FIG. 2J is a cross-sectional view taken along the line IIJ-IIJ shown in FIG. 1D. FIG. 2K is a cross-sectional view taken along the line IIK-IIK shown in FIG. 1D. FIG. 3A is a schematic view showing how to form a fusion bond in the vicinity of the proximal wire insertion hole shown in FIG. 1D. FIG. 3B is a schematic view showing a step that follows the step shown in FIG. 3A. FIG. 3C is a schematic view showing a step that follows the step shown in FIG. 3B. FIG. 4 is an enlarged sectional view of an essential part of the structure before the cutting process obtained through the process shown in FIG. 3C.

  Hereinafter, the present invention will be described based on embodiments shown in the drawings.

  In the present embodiment, a PTCA balloon catheter (hereinafter referred to simply as a balloon catheter) used to dilate a stenosis in a coronary artery in percutaneous coronary angioplasty (PTCA), which is a type of balloon catheter for blood vessel dilation. The invention will be described by way of example.

  As shown in FIG. 1A, the balloon catheter 1 of the present embodiment is a so-called monorail catheter, and includes a balloon portion 10, an outer tube (outer shaft) 20 as a catheter tube, an inner tube (guide wire shaft) 40 and a connector. Have 60.

  The balloon portion 10 is a tubular membrane whose both ends are reduced in diameter. The balloon portion 10 is guided to the narrowing portion of the coronary artery in a state where it is folded and the outer diameter is reduced, and the balloon portion 10 dilates the narrowing portion of the coronary artery by being expanded at the narrowing portion.

  The proximal end 11 of the balloon portion 10 is joined to the outer periphery of the distal end 22 of the outer tube 20 by means such as fusion or adhesion, and the balloon expansion lumen (main lumen) 23 of the outer tube 20 is It is in communication with the internal expansion space 13 of the balloon portion 10. The distal end 12 of the balloon portion 10 is joined to the outer periphery of the distal end 42 of the inner tube 40 by means such as fusion or adhesion. With such a configuration, the internal expansion space 13 of the balloon portion 10 is configured to be liquid-tight to the outside other than the balloon expansion lumen 23. The balloon unit 10 is not particularly limited as long as it has a cylindrical shape, and may have a cylindrical shape or a polygonal cylindrical shape.

  Although the film thickness of the cylindrical film body which comprises the balloon part 10 is not specifically limited, Usually, it is about 15-300 micrometers, Preferably it is about 30-150 micrometers. The outer diameter of the balloon portion 10 at the time of expansion is determined by conditions such as the inner diameter of the coronary artery, but is usually about 1.25 to 10.0 mm, preferably about 1.25 to 7 mm. The axial length of the balloon portion 10 is also determined by conditions such as the size of the intra-coronary stenosis, and is usually about 5 to 50 mm, preferably about 6 to 40 mm. In addition, the balloon part 10 before expanding is folded and wound around the inner tube 40, and the outer diameter is as small as possible.

  The material constituting the balloon portion 10 is preferably a material having a certain degree of flexibility, for example, a copolymer of ethylene and other α-olefin such as polyethylene, polyethylene terephthalate, polypropylene, ethylene-propylene copolymer, etc. Copolymer, ethylene-vinyl acetate copolymer, polyvinyl chloride (PVC), cross-linked ethylene-vinyl acetate copolymer, polyurethane, polyamide, polyamide elastomer, polyimide, polyimide elastomer, silicone rubber, natural rubber, etc. can be used, preferably Are polyethylene, polyethylene terephthalate, polyamide, and polyamide elastomers.

  The outer tube 20 is a tubular body in which a balloon expansion lumen (main lumen) 23 is formed along the axial direction. The balloon expansion lumen 23 is for sending fluid to the internal expansion space 13 of the balloon portion 10 to expand the balloon portion 10 or extracting fluid from the internal expansion space 13 of the balloon portion 10 to contract the balloon portion 10. The lumen of The proximal end 21 of the outer tube 20 is joined to the connector 60, and the distal end 22 of the outer tube 20 is joined to the proximal end 11 of the balloon portion 10. Thereby, the inside of the connector 60, the balloon expansion lumen 23 and the internal expansion space 13 of the balloon portion 10 communicate with each other.

  As shown in FIGS. 2A to 2K, the outer tube 20 is substantially the same outside in the substantially circular cross section over the entire length except for the fusion portion between the inner tube 40 and the outer tube 20 (FIGS. 2B to 2I). It consists of a tube member of diameter and inner diameter.

  The length of the outer tube 20 may be any length, for example, about 500 to 2000 mm, preferably about 1000 to 1500 mm. The outer diameter of the outer tube 20 is not particularly limited, but in the balloon catheter 1 of the present embodiment, the outer diameter is as thin as 0.86 mm or less, preferably 0.80 to 0.86 mm. The inner diameter of the outer tube 20 is not particularly limited, but is, for example, 0.73 mm or less, preferably 0.68 to 0.71 mm. The thickness of the outer tube 20 is not particularly limited, but is, for example, 0.06 to 0.09 mm, preferably 0.065 to 0.085 mm.

  The material constituting the outer tube 20 is preferably made of a fusible, flexible polymer material, for example, polyethylene, polyethylene terephthalate, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer Polymers, polyvinyl chloride (PVC), cross-linked ethylene-vinyl acetate copolymers, polyurethanes, polyamides, polyamide elastomers, polyimides, polyimide elastomers, etc. can be used, and are preferably made of polyethylene, polyamides, polyimides.

  The inner tube 40 is a tubular body in which a wire lumen 43 is formed along the axial direction, through which a guide wire 70 for guiding the balloon catheter 1 into a body cavity is inserted (see FIGS. 1A and 1B) It extends inside the balloon expansion lumen 23 on the side of the inner expansion space 13 of the balloon portion 10 and the distal end 22 of the outer tube 20. The distal end portion 42 of the inner tube 40 is located further to the distal side than the distal end portion 22 of the outer tube 20, is opened distal to the distal end portion 12 of the balloon portion 10, The position-side wire insertion hole 45 is configured.

  The proximal end 41 of the inner tube 40 is opened on the outer surface of the outer tube 20 as a proximal wire insertion hole 44 at the inner tube fusion portion 50 in the middle of the outer tube 20 in the axial direction. The proximal end 41 of the inner tube 40 and the outer tube 20 are joined in a fluid tight manner by the method described later.

  As shown in FIG. 1A, a contrast ring 61 is attached to the outer periphery of a portion of the inner tube 40 located in the internal expansion space 13 of the balloon portion 10, and when the balloon catheter 1 is inserted into a living body, It is possible to confirm the position of the balloon unit 10 by confirming the position of the imaging ring 61 from the outside of the living body by X-ray imaging or the like. Examples of the material of the imaging ring 61 include metals such as gold, platinum and tungsten.

  The length of the inner tube 40 may be any length, for example, about 100 to 500 mm, preferably about 250 to 350 mm. Also, although the proximal wire insertion hole 44 may be at any position of the outer tube 20, it is preferably formed in a range of 50 to 450 mm from the distal end of the outer tube 20, for example, More preferably, it is in the range of 300 mm.

  The outer diameter of the inner tube 40 is determined such that a gap is formed between the inner tube 40 and the outer tube 20, and is not particularly limited, and is, for example, 0.48 to 0.53 mm, preferably 0.49 to 0.51 mm. is there. Further, the inner diameter of the inner tube 12 is not particularly limited as long as the inner diameter of the inner tube 12 can be passed through the used guide wire 70, and is 0.26 to 0.44 mm, preferably 0.30 to 0.42 mm.

  The material constituting the inner tube 40 is preferably made of a fusible, flexible polymer material similar to the outer tube 20, for example, polyethylene, polyethylene terephthalate, polypropylene, ethylene-propylene copolymer A combination of ethylene-vinyl acetate copolymer, polyvinyl chloride (PVC), cross-linked ethylene-vinyl acetate copolymer, polyurethane, polyamide, polyamide elastomer, polyimide, polyimide elastomer, etc. can be used, preferably polyethylene, polyamide, It is a polyimide.

  The connector 60 shown in FIG. 1A is a tubular body having a port provided therein, and the distal end of the connector 60 is the proximal end 21 of the outer tube 20 so that the port communicates with the balloon expansion lumen 23. Are bonded by means such as adhesion or fusion. The proximal end side of the connector 60 is formed in a shape connectable to another medical device such as a PTCA inflator by screwing or the like. A fluid such as saline is fed from the port of the connector 60 to the internal expansion space 13 of the balloon portion 10 through the balloon expansion lumen 23 of the outer tube 20.

  Although the material of the connector 60 is not particularly limited, for example, it is preferable to use a thermoplastic resin such as polypropylene resin, ABS resin, polycarbonate resin, polyamide resin, polyacrylate resin and the like.

  The pressure fluid introduced into the balloon expansion lumen 23 of the outer tube 20 and the internal expansion space 13 of the balloon portion 10 through the port of the connector 60 is not particularly limited. A 50/50 mixed aqueous solution of a permeable medium and saline is used. The radiopaque medium is included in order to confirm the positions of the balloon unit 10 and the outer tube 20 by radiography when the balloon catheter 1 is used. The pressure of the pressure fluid for inflating the balloon portion 20 is not particularly limited, but is about 3 to 25 atm, preferably about 4 to 22 atm in absolute pressure.

  Further, the guide wire 70 is a wire that is inserted into the wire lumen 43 of the inner tube 40 in order to guide the balloon catheter 1 into the body cavity. The guide wire 70 is made of, for example, a single wire or a stranded wire of stainless steel, copper, copper alloy, titanium, titanium alloy or the like, and if necessary, a resin or a hydrophilic polymer substance having lubricity in a wet state Etc. is provided. The outer diameter of the guide wire 70 is not particularly limited, but is preferably 0.25 to 0.38 mm, more preferably. It is 0.25 to 0.36 mm.

  Moreover, it is preferable that the outer tube 20 be coated with a coating material made of a hydrophilic polymer substance having lubricity in a wet state. By covering the outer periphery of the outer tube 20 with such a covering material, it is possible to reduce the insertion resistance when inserting the balloon catheter 1 into a coronary artery or the like. Also, the outer periphery of the balloon portion 10 may be coated with a covering material. By covering the outer periphery of the balloon portion 10 with a covering material, it is possible to reduce the insertion resistance when the balloon portion 10 is inserted into the narrowed portion in the coronary artery.

  The hydrophilic polymer substances include those of natural polymers and those of synthetic polymers. Examples of natural polymers include starch-based polymers, cellulose-based polymers, tannin-nygnin-based polymers, polysaccharide-based polymers, protein-based polymers and the like. Examples of synthetic polymer include PVA resin, polyethylene oxide resin, acrylic acid resin, maleic anhydride resin, phthalic acid resin, water-soluble polyester, ketonaldehyde resin, (meth) acrylamide resin, vinyl Examples thereof include heterocyclic resin, polyamine resin, polyelectrolyte, water-soluble nylon resin, and glycidyl acrylate resin.

  Among these, as a hydrophilic polymer substance that can be suitably used as a coating material for the outer tube 20, particularly, cellulose polymers (for example, hydroxypropyl cellulose), polyethylene oxide resins (for example, polyethylene glycol), and maleic anhydride Acid-based resin (eg, maleic anhydride copolymer such as methyl vinyl ether-maleic anhydride copolymer), acrylamide resin (eg, polydimethyl acrylamide), water-soluble nylon (eg, Toray's “AQ-nylon P-70” “) Or their derivatives. These substances are preferable because they can stably obtain a low coefficient of friction in the wet state.

  When using such a monorail type balloon catheter 1 for dilation of a narrowed portion of a coronary artery, first, the balloon portion 10 is made by bringing the wire lumen 43 of the inner tube 40 along the guide wire 70 inserted to the narrowed portion of the coronary artery. Is guided to the narrowing portion of the coronary artery, and a fluid such as saline is fed into the internal expansion space 13 of the balloon portion 10 through the connector 60 and the balloon expansion lumen 23 of the outer tube 20 to expand the balloon portion 10 To dilate the stenosis in the coronary artery.

  Next, the manufacturing method of the balloon catheter 1 of such a structure is demonstrated.

  First, as shown in FIG. 3A, the distal outer tube 20a and the proximal outer tube 20b to be the outer tube 20 of the balloon catheter 1 and the inner tube 40 of the balloon catheter 1 are prepared.

  The distal outer tube 20a, the proximal outer tube 20b and the inner tube 40 all have a lumen along the central axial direction, and each is a tubular body having an outer diameter, an inner diameter and a wall thickness as described above. is there. Among these, the distal outer tube 20a and the proximal outer tube 20b preferably have substantially the same outer diameter and thickness. Further, although the material of each tube is a fusion-bondable, flexible polymer material as described above, it is preferable that they be formed of the same material so as to be easily fused to each other.

  In this embodiment, the distal outer tube 20a and the proximal outer tube 20b are obtained by cutting one tube at an angle to the central axis and dividing it.

  In the distal outer tube 20a and the proximal outer tube 20b, at least one of the proximal end 20a1 of the distal outer tube 20a and the distal end 20b1 of the proximal outer tube 20b is with respect to the central axis It is preferable to have an obliquely cut shape, and it is more preferable that both of them have a shape cut obliquely to the central axis. With such a shape, it is possible to easily superimpose them. In this embodiment, the end cut at an angle to the central axis is the proximal end 20a1 of the distal outer tube 20a and the distal end 20b1 of the proximal outer tube 20b.

  In addition, at least one of the proximal end 20a1 of the distal outer tube 20a and the distal end 20b1 of the proximal outer tube 20b may have a slit along the central axial direction from the distal peripheral edge. If such a slit is formed, the overlapping area can be widened when overlapping the proximal end 20a1 of the distal outer tube 20a and the distal end 20b1 of the proximal outer tube 20b. Therefore, the strength of the periphery of the proximal wire insertion hole 44 after fusion can be greatly improved.

  It is preferable that the proximal end 11 of the balloon 10 shown in FIG. 1A is previously joined to the distal end of the distal outer tube 20a by means such as fusion or adhesion. However, this bonding can also be performed during formation of the proximal wire insertion hole 44 or after formation of the proximal wire insertion hole 44.

  Once such a distal outer tube 20a and a proximal outer tube 20b are prepared, the inner tube 40 is inserted into the lumen of the distal outer tube 20a. However, before inserting the inner tube 40 into the lumen of the distal outer tube 20a, the lumen (wire lumen 43) of the inner tube 40 is provided with a wire-like mandrel 71 for preventing occlusion of the lumen at the time of fusion. It is preferable to insert it. The wire-like mandrel 71 is a linear body having a substantially circular cross section having an outer diameter substantially equal to the lumen diameter of the inner tube 40, and is made of, for example, a material such as stainless steel. The length of the wire-like mandrel 71 is not particularly limited as long as it can prevent occlusion of the lumen, but is preferably 10 to 50 mm longer than the inner tube 40.

  Next, the inner tube 40 into which the wire-like mandrel 71 is inserted is inserted into the lumen (balloon expansion lumen 23) of the distal outer tube 20a and placed inside the lumen of the distal outer tube 20a. At this time, it is preferable to position the proximal end 41 of the inner tube 40 so as to project 1 to 5 mm from the proximal end 20a1 of the distal outer tube 20a. Also, the proximal end 72 of the wire-like mandrel 71 is preferably positioned so as to protrude 10 to 20 mm from the proximal end 41 of the inner tube 40.

  Next, as shown in FIG. 3B, with the proximal end 41 of the inner tube 40 protruding from the proximal end 20a1 of the distal outer tube 20a, the distal end of the proximal outer tube 20b The distal end 20b1 of the proximal outer tube 20b and the distal end of the proximal outer tube 20b are located on the outer periphery of 20b1 so that the balloon expansion lumens 23 of the distal outer tube 20a and the proximal outer tube 20b communicate with each other. The proximal end 20a1 of the outer tube 20a is partially overlapped.

  Thereafter, as shown in FIG. 3C, the proximal end 41 of the inner tube 40 and the proximal end of the distal outer tube 20a using a heat shrink tube 78 and a hot air jet 80, or by other means. 20a1 and the distal end 20b1 of the proximal outer tube 20b are fused. At this time, before the proximal end 20a1 of the distal outer tube 20a and the distal end 20b1 of the proximal outer tube 20b overlap, the balloon expansion lumen 23 of the proximal outer tube 20b is notched. Preferably, the mandrel 73 is inserted.

  The notched mandrel 73 is formed by cutting out one end side of a round bar having an outer diameter substantially equal to the lumen diameter of the outer tubes 20a and 20b with the notched portion 74, and in the present embodiment, the notched portion is formed. The cross-sectional shape of the broken portion is substantially crescent-shaped, which is the same as the cross-sectional shape of the balloon expansion lumen 23 as shown in FIGS. 2B to 2K. The material of the notched mandrel 73 is not particularly limited, but stainless steel or the like is preferable. Further, the length of the cutout mandrel 73 is preferably about 100 to 150 mm longer than the proximal outer tube 20b, and it is preferable that the cutout be formed with a length of 5 to 20 mm.

  The method of fusion bonding is not particularly limited, and various fusion methods such as heat fusion by hot air or light beam or fusion by ultrasonic waves can be adopted. When the heat-shrinkable tube 78 is used, the material of the heat-shrinkable tube 78 is not particularly limited, but one having relatively excellent heat resistance is preferable. For example, it is preferable to use a heat-shrinkable tube made of fluorocarbon resin. The length of the heat shrinkable tube 78 is usually 10 to 30 mm, and the inner diameter of the heat shrinkable tube 78 is preferably 0.1 to 0.5 mm larger than the outer diameter of the outer tube members 10 and 13. Moreover, the thickness of the heat-shrinkable tube 78 is usually 0.1 to 1.0 mm.

  A heat shrinkable tube 78 is put on a portion to be fused, and then the portion is covered with a hot air blowout mold 80 provided with a hot air blowout port for blowing out hot air to the inner peripheral surface, and heat shrinks by applying hot air. The tube 78 is heated. The heating softens the inner tube 40 and the outer tubes 20a and 20b, and the heat-shrinkable tube 78 contracts to abut the inner tube 40 and the outer tubes 20a and 20b and the distal outer tube 20a and the proximal outer side. An external force is applied to the overlapping portion with the tube 20b. The heating temperature and the heating time vary depending on the materials of the inner tube 40 and the outer tubes 20a and 20b and the kind of the heat shrinkable tube 78, but usually the temperature is 150 to 250 ° C. and the heating time is 10 to 60 seconds .

  After heating, the heat-shrinkable tube 78 is cooled, the heat-shrinkable tube 78 is cut and removed, and the wire-like mandrel 71 and the notch mandrel 73 are removed. The state is shown in FIG.

  As shown in FIG. 4, the proximal end 41 of the inner tube 40 and the proximal end 20 a 1 of the distal outer tube 20 a are fused together, and the proximal end 41 of the inner tube 40 is in close proximity The distal end 20b1 of the extra-lateral tube 20b is fused. Further, the proximal end 20a1 of the distal outer tube 20a and the distal end 20b1 of the proximal outer tube 20b are fused. Then, between the proximal end portion 41 of the inner tube 40 and the distal end portion 20b1 of the proximal outer tube 20b, the wire lumen proximally exposed so that the wire lumen 43 of the inner tube 40 is exposed to the outside of the outer tube 20. Side openings 52 are formed.

  In the fusion-bonded portion 50 in the fusion-bonded state, a thin-walled portion 41 a made of the material constituting the proximal end 41 of the inner tube 40 is formed. In addition, by fusing the proximal end 20a1 of the distal outer tube 20a and the distal end 20b1 of the proximal outer tube 20b, the circumferential edge of the wire lumen proximal opening 52 is obtained. Each raised portion 54 is also formed (see FIGS. 4 and 2G). Although it depends on the fusion conditions and the like, it is rare that the unfused portion 56 which is a gap is left inside the swelled portion 54.

  The fused part 50 in the fused state has a cross-sectional shape as shown in FIG. 1D and FIGS. 2A to 2K. In this embodiment, a portion of the wire lumen 43 is exposed to the outside with a predetermined cutting length L1 in the distal direction from a predetermined position (proximal cutting end C1) of the proximal opening 52 of the wire lumen 43 Then, a thin-walled portion 41a (see FIG. 4) including a part of the outer periphery of the inner tube 40 after fusion bonding is cut with a razor or the like to a predetermined depth D1 (see FIGS. 1B and 2D to 2F). The depth D1 is preferably about 1/10 to 1/5 of the inner diameter of the inner tube 40.

  As shown in FIG. 1D, the proximal cut end C1, which is a cutting start position at a cutting length L1 for cutting a part of the outer periphery of the inner tube 40 after fusion, has a wire lumen proximal opening 52 after fusion. The most distal opening edge position 52a located at the most distal side among the edges of the wire and the most proximal opening edge position 52b located at the most proximal side among the edges of the wire lumen proximal opening 52 after fusion Located between Preferably, the proximal cut end C1 is closer to the most distal opening edge position 52a than the most recent opening edge position 52b. If the proximal excision end C1 is too proximal to the above-described position, there is a risk of cutting off the unfused portion 56 having a gap as shown in FIG. 2G. There is a possibility that the balloon dilation lumen 23 may leak because the balloon dilation lumen 23 communicates with the outside.

  The farthest opening edge position 52a is the most distal part of the portion where the wire lumen 43 is exposed to the outside of the outer tube 20 in a state before cutting off a part of the outer periphery of the inner tube 40 It is a position. Also, the most proximal opening edge position 52b is the most proximal position of the recessed portions of the outer tube 20 formed to communicate with the wire lumen 43, and usually, the proximal outer side melted at the time of fusion It corresponds to the most proximal portion of the portion corresponding to the tube 20b.

  The distal end 41 of the inner tube 40 is the distal end of the outer tube 20a. It is located on the proximal side of the most distal fusion position 50b, which is the most distal position of the portion fusion-bonded to the inner circumferential surface. If the distal excision end C2 is positioned distal to the most distal fusion position 50b, the balloon dilation lumen 23 may leak.

  As shown in FIG. 1D, the distance L2 between the most distal fusion position 50b and the distal resected end C2 is preferably 5 to 11 mm. The distance L3 between the proximal excision end C1 and the most recent opening edge position 52b is approximately the same as the distance L2, but is not necessarily the same. The distance L4 between the most distal opening edge position 52a and the proximal excision end C1 is preferably smaller than the distance L3, and more preferably, L3 / L4 is 2.5 to 8.

  As shown in FIG. 1B and FIG. 1C, by cutting off a part of the outer periphery of the inner tube 40 in the fusion bonded part 50 at a predetermined depth D1 along the axial direction with a cut length L1 shown in FIG. 1D. A distal wire insertion hole 44 communicating with the wire lumen 43 is formed at the distal cut end C2. Further, in a portion corresponding to the cut length L1, a hook-shaped passage 55 for guiding the withdrawal or introduction of the guide wire 70 is formed.

  After the formation of the proximal wire insertion hole 44 in this manner, as shown in FIG. 1A, the distal end 12 of the balloon portion 10 is fused or adhered to the distal end 42 of the inner tube 40, etc. The monorail type balloon catheter 1 can be manufactured by bonding the connector 60 to the proximal end of the outer tube 20 by means such as fusion bonding or adhesion.

  According to the method of manufacturing the balloon catheter 1 of the present embodiment, as shown in FIG. 4, after fusion in communication with the wire lumen 43 of the inner tube 40 located on the outer periphery of the distal end of the proximal outer tube 20 b After fusion, the wire lumen 43 is partially exposed to the outside at a predetermined ablation length L1 (see FIG. 1B) in the distal direction from the predetermined ablation position C1 of the wire lumen proximal opening 52 of A part (thin portion 41 a) of the outer periphery of the inner tube 40 is cut out.

  That is, in the present embodiment, in the fusion-bonded portion 50 of the wire lumen 43, the thin side wall (thin portion 41a) formed only of the material constituting the inner tube 40 is cut away along the axial direction. . Therefore, in the balloon catheter 1 according to the present embodiment, the thin side wall (thin portion 41a) is less likely to be torn at the time of use, and the guide wire 70 is prevented from being caught (stacked) in the torn side wall. As a result, the operation of the catheter 1 along the guide wire 70 becomes smooth and easy.

  The embodiment described above is described to facilitate understanding of the present invention, and does not limit the present invention at all. Each element disclosed in the present embodiment also includes all design changes and equivalents that fall within the technical scope of the present invention, and various suitable modifications are possible.

  For example, the catheter according to the present invention may be a balloon catheter for dilatation of blood which is used other than percutaneous coronary angioplasty (PTCA). As an example of such a balloon dilatation balloon catheter, there can be mentioned a balloon dilatation balloon catheter used for dilation of blood vessels such as limbs and the like. In addition, the catheter according to the present invention may be a balloon catheter other than a balloon catheter for blood vessel dilation, and as an example of such a balloon catheter, a balloon catheter used for dilation of the upper ureter can be mentioned. Furthermore, if the catheter according to the present invention is a so-called monorail catheter, it may be a catheter having no balloon portion. When the catheter according to the present invention is a catheter having no balloon portion, the main lumen can be used for other purposes than balloon dilation.

DESCRIPTION OF SYMBOLS 1 ... PTCA balloon catheter 10 ... Balloon part 11 ... Proximal end 12 ... Distal end 13 ... Space for internal expansion 20 ... Outer tube (outer shaft)
21 ... proximal end 22 ... distal end 23 ... lumen for balloon expansion (main lumen)
40 ... Inner tube (guide wire shaft)
DESCRIPTION OF SYMBOLS 41 ... Proximal end 42 ... Distal end 43 ... Wire lumen 44 ... Proximal wire penetration hole 45 ... Distal wire penetration hole 50 ... Inner tube fusion part 60 ... Connector 61 ... Contrast ring 70 ... Guide wire 71 Wire-like mandrel 72 Proximal end 73 Notched mandrel 74 Notched portion 78 Heat-shrinkable tube 80 Hot-air jet type

Claims (5)

Providing a distal outer tube and a proximal outer tube, each having a main lumen axially formed therein;
Providing an inner tube in which the wire lumen is formed along the axial direction;
Placing the inner tube inside the main lumen of the distal outer tube;
The proximal end of the inner tube is ejected from the proximal end of the distal outer tube and positioned around the distal end of the proximal outer tube such that the respective main lumens communicate The distal end of the proximal outer tube partially overlaps the proximal end of the distal outer tube, and the proximal end of the inner tube and the proximal end of the distal outer tube Fusion bonding with the distal end of the lateral outer tube;
A predetermined ablation length in a distal direction from a predetermined position of the wire lumen proximal opening after fusion in communication with the wire lumen of the inner tube located on the outer periphery of the distal end of the proximal outer tube Cutting a portion of the outer periphery of the inner tube after fusion so that a portion of the wire lumen is exposed to the outside;
I have a,
The proximal excision end, which is the start position of the trimming step, is the most distal open end position located most distally among the edges of the proximal end of the wire lumen after fusion, and the wire after fusion A method of manufacturing a catheter located between the most proximal opening edge position located at the most proximal side of the rim of the lumen proximal opening . The method according to claim 1 , wherein the proximal resected end is closer to the most distal opening edge position than the closest opening edge position. The distal end of the distal end of the inner tube is fused to the inner peripheral surface of the distal outer tube. method for producing a catheter according to claim 1 or 2 located at the proximal side of the distal-most fusion position. The catheter manufactured by the method in any one of Claims 1-3 . An outer tube whose main lumen is formed along the axial direction;
A wire lumen formed internally along the axial direction, and an inner tube extending axially inside the main lumen of the outer tube,
The proximal end of the inner tube is fused to the inner wall of the outer tube midway in the axial direction of the outer tube to form an inner tube fusion portion along the axial direction,
The fusion is performed so that a part of the wire lumen is exposed to the outside at a predetermined cutting length in a distal direction from a predetermined position of the proximal end of the wire lumen after fusion in communication with the wire lumen of the inner tube. part of the outer periphery of the front Kenai tubes after wearing have been cut away, proximal resection margin located at the starting position, the distal-most among the edges of the wire lumen proximal opening after fusing A catheter located between the most distal opening edge position located and the most proximal opening edge position located most proximal among the edges of the wire lumen proximal opening after fusion .

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