JP2003102844A - Stent delivery catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stent delivery catheter in which a stent can be disposed with good operability even at a curved narrowing part and the drop or the movement of the stent does not occur. SOLUTION: The stent delivery catheter delivers the stent for treating the narrowed part in an organism to the narrowed part. The stent delivery catheter comprises a foldable balloon having a truncated conical shape tapered part and a cylindrical straight tube part at the distal end in such a manner that the stent is arranged in a contracted state on the outer surface of the folded balloon. The catheter further comprises an inner tube for forming a guide wire lumen extended in the balloon, and a movement preventing mechanism for preventing the catheter of the stent fixed only to the inner surface of the balloon from moving in a lengthwise direction.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to blood vessels, esophagus, trachea,
The present invention relates to a delivery catheter for introducing and placing a stent used for dilatation treatment of a stenosis formed in a urethra, a bile duct, etc., and particularly to a delivery catheter for introducing and placing a stent in a stenosis of a coronary artery. is there.

[0002]

2. Description of the Related Art A stent is widely used as a device for effectively securing a lumen by being left in a stenosis formed in a blood vessel, an esophagus, a trachea, a urethra, a bile duct or the like. The stent is introduced into the vessel in the folded state,
After being placed in the desired constriction, it is expanded to a predetermined size and placed.

Stents are roughly classified into the following two types according to the mechanism when expanded to a predetermined size. One is a stent made of shape memory alloy or the like, which is a self-expandable stent that can be expanded without mechanical expansion of the stent. The other is a stent that requires mechanical expansion of a stent, and is generally a balloon expansion type expanded by a known balloon catheter used for expanding a vessel, particularly an artery and a vein. Stent
on-expandable sentence).

The balloon-expandable stent does not have an expanding function in itself, and in order to leave the stent in a desired stenosis, after the stent mounted on the balloon portion of the balloon catheter is placed up to the desired stenosis, A method in which a balloon is expanded and the stent is plastically deformed by the expansion force of the balloon so as to be in close contact with the inner surface of the stenosis is generally performed.

When the balloon-expandable stent is placed by the above method, it is necessary to insert the balloon catheter with the stent attached to the balloon portion up to the stenosis, and the stent moves on the balloon and drops off from the balloon catheter during insertion. There is a risk. Further, a balloon generally used for a balloon catheter has a shape in which a truncated cone-shaped tapered portion is formed in front of and behind a straight tubular portion that expands into a cylindrical shape, and a balloon-expandable stent is formed on the outer surface of the straight tubular portion. Is installed. Even if the stent moves on the balloon during insertion and does not fall off the balloon catheter, if the stent moves before and after the straight tube, one end of the stent will be located on the outer surface of the tapered portion of the balloon. . Since the balloon in this portion expands only in a tapered shape, insufficient expansion of the stent occurs and restenosis (R
The risk of causing estenosis is extremely high.

From the above viewpoints, a prior art for preventing the stent from falling out or moving is disclosed in a balloon catheter used for placing a balloon-expandable stent.

Japanese Unexamined Patent Publication No. 8-164210 discloses an intravascular support device having means for encapsulating a stent. In the prior art, encapsulation is achieved by heating, pressurizing, and cooling the balloon so that it expands around the collapsed stent.

However, heating and pressurizing such a balloon,
In addition, the balloon is mechanically or thermally damaged due to the cooling process, and there is concern that the compressive strength may be reduced and pinholes may be generated.

Japanese Unexamined Patent Publication (Kokai) No. 9-276414 discloses a technique for forming a layer having a large friction coefficient on the outer surface of a balloon as a stent delivery system having a stent holding means for preventing the stent from moving from the balloon, and the inside of the balloon. There is disclosed a technique in which a portion having a small diameter (saddle or sheet) is provided in the inner tube existing in the above, and the stent is arranged on the outer surface of the balloon on the sheet portion.

When a layer having a large friction coefficient is formed on the outer surface of the balloon, the manufacturing process of the balloon becomes complicated, which causes a problem in cost. Further, when the inner tube is provided with a portion having a small diameter and the stent is arranged on the outer surface of the balloon on the seat portion, since the guide wire is inserted inside the inner tube, a certain inner diameter or more is required. However, it is obvious that the wall thickness of the inner tube is thinner than the others, and there is a risk that the inner tube of the seat part will kink when the stent is inserted into the stenosis and the operability will be extremely reduced. is there.

Further, in Japanese Patent Laid-Open No. 11-128366, two collars are arranged on the outer periphery of a portion located inside the balloon so as to face the other and are spaced in parallel, and a tubular adapter is provided on the outer periphery of the portion between the two collars. Disclosed is a catheter structure in which a balloon is wrapped around a collar and a tubular adapter to form a mechanism to prevent axial migration of a stent disposed around the balloon.

In this prior art, there is little risk that the catheter operability will be deteriorated due to the kink of the inner tube which can occur in the prior art of Japanese Patent Application Laid-Open No. 9-276414, but there are two parts located inside the balloon. Since the collar is fixed, the flexibility of the balloon portion is extremely reduced, and it becomes a problem that the stent cannot be placed in the bent stenosis.

[0013]

SUMMARY OF THE INVENTION In view of the above problems, the problem to be solved by the present invention is to provide a balloon in which a stent can be placed with good operability even in a bent stenosis and the stent is mounted. It is an object of the present invention to provide a stent delivery catheter in which the stent does not drop out or move when the catheter is inserted into a stenosis.

[0014]

In order to solve the above problems, there is provided a stent delivery catheter for delivering a stent for treating a stenosis in a living body to the stenosis, wherein the stent delivery catheter has a distal end portion. It has a rear end portion, a hub having a port for supplying pressure fluid at the rear end portion, and a conical truncated taper portion and a cylindrical straight pipe portion at the front end portion, which are foldable. The balloon has a flexible balloon, and the stent is disposed in a contracted state on the outer surface of the folded balloon, and an inner tube defining a guide wire lumen extends inside the balloon, and only the inner surface of the balloon is provided. A stent for preventing movement of the stent fixed to the longitudinal direction of the stent delivery catheter is provided. You configure the delivery catheter.

It is preferable that the movement prevention mechanism is provided on a front end side and a rear end side of the balloon, and the movement prevention mechanism is a tubular member.

It is preferable that the movement preventing mechanism extends only to the taper portion of the balloon and does not extend to the straight tube portion of the balloon. The movement preventing mechanism and the movement preventing at the fixing portion of the balloon are preferable. When the outer diameter of the mechanism is D1, and the outer diameter of the movement preventing mechanism of the portion extending inside the balloon is D2, 1 ≦ (D2 / D1) is more preferable, and 1 ≦ (D2 / D1 ) ≦ 2 is more preferable.

The movement preventing mechanism is preferably made of a material that can be fused with the balloon, the movement preventing mechanism is made of polyamide or polyamide elastomer, and the balloon is made of polyamide elastomer or a blend material of polyamide elastomers. More preferably, the movement prevention mechanism is made of polyester or polyester elastomer, and the balloon is made of polyester elastomer or a blend material of polyester elastomers.

Further, it is preferable that an X-ray opaque marker is attached to the movement preventing mechanism.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Various embodiments of a stent delivery catheter according to the present invention will be described in detail below with reference to the drawings.

The stent delivery catheter according to the present invention is a high-speed exchange type catheter having a guide wire lumen 5 only on the distal side of the catheter as shown in FIG.
Alternatively, any structure of an over-the-wire type catheter having a guidewire lumen 5 over the entire length of the catheter as shown in FIG. 1 can be adopted.

The structure of the stent delivery catheter is not limited as long as the guide wire lumen 5 and the inflation lumen 6 are provided. That is, the outer tube 2 and the inner tube 3 are arranged in a coaxial double tube, and the inner tube has the guide wire lumen 5 and the inflation lumen 6 defined by the inner surface of the outer tube and the outer surface of the inner tube. A coaxial (co-axial) type structure may be used, or a bi-axial type structure using a dual lumen tube 7 in which the guide wire lumen 5 and the inflation lumen 6 are arranged in parallel may be used. Further, even if the structure is other than those exemplified above, the effect of the present invention is not limited at all.

The balloon 1 in the present invention preferably has a cylindrical straight pipe portion 1A and a truncated cone-shaped tapered portion 1B in front of and behind the straight pipe portion, but the taper angle in the tapered portion 1B is limited. However, any angle can be selected according to the purpose.

The present invention will be described in detail below by exemplifying the case where the structure of the stent delivery catheter is a coaxial type.

The balloon 1 is foldable, and the balloon 1 is wound along the inner tube 3 while depressurizing the inside of the balloon 1 so that it can be folded into a long shape. By disposing the stent in a contracted state on the outer surface of the folded balloon 1, preferably the outer surface of the straight tube portion 1A, the stent can be inserted into the body using a balloon catheter.
However, when the balloon 1 of the stent delivery catheter (FIG. 1) without the movement prevention mechanism 8 is folded and the stent 11 in the contracted state is arranged (FIG. 12),
The outer diameter of the stent 11 in the contracted state is larger than the outer diameters of the straight tube portion 1A and the tapered portion 1B of the folded balloon 1, and due to friction with the hemostack valve and the guide catheter that occur when the stent 11 is inserted into the body. , The stent 11 is not only able to move on the surface of the balloon 1 but there is a risk of falling out of the catheter.

On the other hand, the balloon 1 of the stent delivery catheter (FIG. 7) according to the present invention provided with the movement preventing mechanism 8.
When the stent 11 in a contracted state is placed by folding the tape (FIG. 13), the tapered portion 1 of the folded balloon 1
The outer diameter of B is the stent 1 in a contracted state by the movement preventing mechanism 8.
1 is larger than the outer diameter of the balloon 1 of the stent 11
It is possible to suppress the movement on the surface and the dropout from the catheter.

The movement preventing mechanism 8 is preferably provided on the front end side and the rear end side of the balloon 1 as illustrated in FIG. By providing the movement prevention mechanism 8 on the front end side and the rear end side of the balloon 1, when the stent is inserted into the stenosis, the stent is effectively prevented from moving in the front end direction and the rear end direction of the stent delivery catheter. Therefore, the most dangerous stent can be prevented from falling off.

The movement prevention mechanism 8 is preferably fixed only to the inner surface of the balloon 1. Since the movement preventing mechanism 8 is fixed only to the inner surface of the balloon 1 and not to the outer surface of the inner tube 3, the flexibility and rigidity of the inner tube 3 are not affected. Therefore, the guide wire operability when inserting the stent into the stenosis is not different from the operability when inserting a general balloon catheter into the stenosis, and good operability can be realized.

Here, the movement preventing mechanism 8 is preferably a tubular member because it can be easily and inexpensively manufactured by utilizing a known extrusion molding technique. The tubular member is preferable as a movement preventing mechanism because various processes (expansion, diameter reduction, etc.) described later can be easily performed. In addition, since the thickness of the tubular member can be easily controlled during extrusion molding, the rigidity of the part where the movement prevention mechanism is present can be easily optimized, and the rigidity of the balloon part can be made more continuous. It is possible to make a distribution. That is, when the stent 11 is delivered to the stenosis part in the living body, the stent 1
It is possible to easily provide a stent delivery catheter with a low risk of kinks or the like that may occur at the boundary between 1 and the movement prevention mechanism 8. Japanese Patent Laid-Open No. 11-12, which is a prior art
In view of the shape of the collar disclosed in Japanese Patent No. 8366, it is apparent that there are major problems in terms of time and manufacturing cost in optimizing rigidity by changing the thickness of the collar, that is, the shape of the collar. .

As described above, it is preferable that the movement preventing mechanism 8 is provided on each of the front end side and the rear end side of the balloon 1, but a tubular member is provided on the front end side and the rear end side of the balloon 1. Not only the embodiment (FIG. 7) to be provided, the outer tube 2 can be extended inside the balloon 1 to form the movement preventing mechanism 8. (FIG. 8) When the outer tube 2 is extended inside the balloon 1,
Since the step of fixing the rear end side movement prevention mechanism 8 to the balloon 1 can be omitted, the efficiency of the manufacturing process can be improved.

In order to prevent the stent 11 from moving more efficiently, it is preferable that the movement preventing mechanism 8 extends only in the tapered portion 1B of the balloon 1 and not in the straight pipe portion 1A. Regarding the outer diameter D2 of the movement preventing mechanism 8 of the portion extending inside the balloon 1 and the outer diameter D1 of the movement preventing mechanism 8 at the fixed portion of the balloon 1, it is more preferable that the relation 1 ≦ (D2 / D1) is established. preferable.

In this case, when the balloon 1 is folded, the outer diameter D2 of the movement preventing mechanism 8 existing inside the taper portion 1B.
However, since the outer diameter of the taper portion 1B of the folded balloon 1 is larger than the outer diameter D1 of the movement preventing mechanism 8 at the portion fixed to the balloon 1, the outer diameter of the taper portion 1B of the folded balloon 1 is outside the contracted stent 11 by the movement preventing mechanism 8. The diameter becomes larger than the diameter, and it becomes possible to suppress the movement of the stent 11 on the surface of the balloon 1 and the dropout from the catheter.

However, in the case of (D2 / D1)> 2, the outer diameter of the folded tapered portion 1B becomes much larger than the outer diameter of the stent 11 in the contracted state, and the outer diameter of the folded tapered portion 1B itself. Becomes resistance and the stent 11
The risk of hindering the placement of the stenosis in the desired stenosis increases.
Therefore, it is more preferable that the relationship of 1 ≦ (D2 / D1) ≦ 2 holds.

Regarding the movement preventing mechanism 8, there is no particular limitation on the means for making the outer diameter D2 of the portion extending inside the balloon 1 different from the outer diameter D1 at the portion fixed to the balloon 1. That is, a method of expanding one end of a tubular member having an outer diameter of D1 to have an outer diameter D2 and a method of reducing one end of a tubular member having an outer diameter of D2 to have an outer diameter D1 (FIG. 9). ,
A method (FIG. 10) or the like in which another tubular member is joined to one end of a tubular member having an outer diameter of D1 to form the outer diameter D2 can be implemented.

By fixing the movement preventing mechanism 8 to the inside of the balloon 1, the cross-sectional area of the inflation lumen 6 on the rear end side of the balloon 1 is reduced, which may delay the inflation time of the balloon. On the other hand, if an attempt is made to secure the cross-sectional area of the inflation lumen 6, the movement preventing mechanism 8 is fixed to increase the outer diameter of the fixed portion, which may cause resistance when the catheter is inserted.
Therefore, it is preferable that the movement preventing mechanism 8 is made of a material that can be fused with the balloon 1 to reduce the diameter of the fixed portion.

The material of the movement preventing mechanism 8 and the balloon 1 is not particularly limited as long as they can be fused to each other. For example, polyolefin, polyolefin elastomer,
It is possible to select and use a fusible combination from polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, polyurethane elastomer and the like. As long as it is a fusion-bondable combination, a blended material of two or more kinds of these resin materials or a material having a multilayer structure by laminating two or more kinds of materials may be used. However, general characteristics required for balloons for stent expansion (compression strength sufficient to expand the stent, flexibility capable of following the bent portion, re-entryability into the stenosis generally called reclosability, compliance characteristics) Etc., the balloon 1 is a polyamide elastomer or a blended material of polyamide elastomers and the movement preventing mechanism 8 is a polyamide or a polyamide elastomer, or the balloon 1 is a polyester elastomer or a blended material of polyester elastomers and a movement prevention. The mechanism 8 is preferably polyester or polyester elastomer.

The method of joining the balloon 1 to the outer tube 2 and the inner tube 3 is not particularly limited, and a known technique, that is, bonding with an adhesive, fusion bonding or the like can be used. Further, the composition, chemical structure, and curing type of the adhesive used are not limited. From the point of view of composition and chemical structure, urethane type, silicone type, epoxy type, cyanoacrylate type adhesives can be used, and from the aspect of curing type, two-liquid mixing type, UV curing type, water absorption curing type An adhesive such as a heat-curable adhesive or a radiation-curable adhesive can be used. However, when an adhesive is used, the hardness of the joints of the balloon 1 and the outer tube 2 and the balloon 1 and the inner tube 3 after curing to the extent that the rigidity of the joints does not change discontinuously before and after the joints. It is preferable to use an adhesive having the following properties, and it is possible to select the adhesive in consideration of the rigidity of the balloon 1, the outer tube 2, and the inner tube 3.

As a method for manufacturing the balloon 1, there are dipping molding, blow molding and the like, and a suitable method can be selected. However, in order to realize a sufficient compressive strength required for a balloon for stent expansion. Blow molding is preferred. For example, first, a tubular parison of arbitrary size is formed by extrusion molding or the like. By arranging the tubular parison in a mold having a shape corresponding to the shape of the balloon and stretching in the axial direction and the radial direction by a biaxial stretching process, a balloon having the same shape as the mold can be molded. . The biaxial stretching step may be performed under heating conditions or may be performed multiple times. The axial stretching may be performed simultaneously with or before and after the radial stretching. Further, an annealing treatment may be performed to stabilize the shape and size of the balloon.

The material of the inner tube 3 has no influence on the effect of the present invention and is not particularly limited.
In the case of the coaxial structure shown in FIG. 3, polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, polyurethane elastomer or the like can be used as the inner tube 3. Since the lumen 5 is defined, polyethylene is preferable, and high density polyethylene is particularly preferable in view of slidability of the guide wire. It is also possible that the inner tube 3 has a multi-layer structure and the innermost layer is made of high-density polyethylene and the outermost layer is made of a material capable of being bonded or fused to the balloon 1 in order to secure the slidability of the guide wire. Further, in order to further enhance the slidability of the guide wire, it is possible to apply a lubricous coating such as silicon or polytetrafluoroethylene to the inner surface of the inner tube 3. In the case of the biaxial structure and other cases, it is possible to select a suitable material in consideration of the above contents.

The material of the outer tube 2 is not particularly limited, like the inner tube 3, and polyolefin, polyolefin elastomer, polyester, polyester elastomer, polyamide, polyamide elastomer, polyurethane, polyurethane elastomer, etc. can be used.

The material forming the hub 9 includes polycarbonate, polyamide, polyurethane, polysulfone,
Polyarylate, styrene-butadiene copolymer, polyolefin and the like can be preferably used.

It is also possible to attach the radiopaque marker 4 to the end of the portion of the movement preventing mechanism 8 that extends inside the balloon 1. In this case, the inner tube 3
The radiopaque marker 4 that is usually present on the outer surface of the inner tube 3 is unnecessary, and the rigidity of the inner tube 3 becomes discontinuous when the radiopaque marker 4 is fixed, and the inner tube 3 is inserted during catheter insertion due to the discontinuity of rigidity. A kink of the tube 3 can be suppressed, and higher operability can be realized.

The X-ray opaque marker 4 may be made of any material having X-ray opacity, and the type of material such as metal or resin is not limited. Further, the method for fixing the radiopaque marker 4 is not limited.

The outer surface of the stent delivery catheter can be coated with a hydrophilic coating to facilitate insertion. That is, it is preferable to apply a hydrophilic coating to the portion that comes into contact with blood, which exhibits lubricity when coming into contact with blood. The type of hydrophilic coating is not particularly limited, and hydrophilic polymers such as poly (2-hydroxyethylmethacrylate), polyacrylamide, polyvinylpyrrolidone and the like, or blends thereof can be preferably used, and the coating method is also not particularly limited.

Further, a hydrophobic coating is applied to the outer surface of the balloon 1 for the purpose of preventing the balloon 1 from slipping during post-dilatation after stent expansion and making positioning difficult on the surface of the balloon 1. be able to. The type of hydrophobic coating is not particularly limited, hydrophobic polymers such as silicon can be preferably used, and the coating method is also not particularly limited.

The stent 11 according to the present invention may be any balloon expandable stent, and the material is not particularly limited,
Stainless steel such as SUS316 can be preferably used. Further, the design of the stent 11 is not limited at all.

[0046]

EXAMPLES Specific examples and comparative examples according to the present invention will be described in detail below, but it is obvious that the present invention is not limited to the following examples. (Example 1) Polyamide elastomer (trade name: PEB
AX7033SA01; manufactured by elf atomchem)
To produce a tubular parison (inner diameter 0.51 mm, outer diameter 1.02 mm) by extrusion molding, and then
Using this parison, the outer diameter of the straight pipe part was 3.0 mm and the inner diameter of the joint of the movement prevention mechanism was 0.9 mm by the biaxial stretch blow molding method.
A 5 mm balloon was made. The inner tube (inner diameter 0.42 mm, outer diameter 0.56 mm) and the outer tube (inner diameter 0.71 mm, outer diameter 0.88 mm) are made of polyamide elastomer (trade name: PEBAX7233SA01;
It was produced by extrusion molding using elf atomchem). The movement prevention mechanism on the balloon tip side is a tubular member (inner diameter 0.65 mm, outer diameter 0.79 mm),
Polyamide elastomer (trade name: PEBAX7033
SA01; manufactured by elf atomchem) was used for extrusion molding. The movement prevention mechanism on the rear end side of the balloon is a tubular member (inner diameter 0.71 mm, outer diameter 0.88 m).
m) and polyamide elastomer (trade name: PEBA
X7033SA01; manufactured by elf atomchem) was used for extrusion molding. The stent is SUS31
6L tube (inner diameter 1.80mm, outer diameter 2.05m
m) was cut into a desired pattern by laser processing and then electrolytically polished.

After the movement preventing mechanism on the front end side and the movement preventing mechanism on the rear end side were joined to the balloon by heat welding, the outer tube and the balloon were joined by heat welding. Approximately 180 mm in the circumferential direction on the outer peripheral surface of the outer tube, which is about 200 mm from the joint of the outer tube and the balloon to the rear end side.
The cut portion was produced by cutting. The inner tube was inserted from the cut portion, and the inner tube and the outer tube were arranged in a coaxial double tube shape. At this time, one end of the inner tube is aligned with the cut portion, and the other end is positioned closer to the tip side than the balloon by penetrating the inside of the balloon, and then the outer tube and the inner tube are joined by heat welding at the cut portion, The balloon and the inner tube were joined by heat welding on the balloon tip side. At the time of joining, a core material having an arbitrary size coated with a highly lubricating material such as polytetrafluoroethylene was appropriately used to secure an inflation lumen or a guide wire lumen.

While decompressing the inside of the balloon, the balloon was folded into a triset shape (the number of folded wings was 3), and the deflated stent was placed in the straight tube portion of the balloon.
The heat-shrinkable tube placed on the outer surface of the stent was contracted to bring the stent in the contracted state into close contact with the outer surface of the balloon. Finally, the heat-shrinkable tube removed was used as a sample of the tip portion of the high-speed exchange-type stent delivery catheter.

Example 2 The same procedure as in Example 1 was carried out except that the outer tube was used as the movement preventing mechanism on the rear end side of the balloon.

(Embodiment 3) The movement preventing mechanism on the balloon tip side uses the same tubular member as in Embodiment 1, the outer diameter of one end is expanded to 1.20 mm, and the expanded portion is tapered on the balloon tip side. Extended to the department. The movement preventing mechanism on the balloon rear end side uses the same tube member as in Example 1, expands the outer diameter of one end to 1.20 mm, and extends the expanded portion to the taper portion on the balloon rear end side, and Example 1 except that the inner diameter of the joint portion of the movement prevention mechanism of the balloon was set to 1.25 mm.
Was prepared in the same manner as in.

(Embodiment 4) An X-ray opaque marker (inner diameter: 0.83 mm;
An outer diameter of 0.90 mm, made of platinum) is adhered and fixed using a two-liquid mixed urethane adhesive (UR0531; made by HB Fuller), and the radiopaque marker is tapered on the balloon tip side. It is located at the boundary between the straight pipe and the pipe. In addition, an X-ray opaque marker (inner diameter 0.92 mm, outer diameter 1.00 mm, made of platinum) is attached to the end of the movement prevention mechanism on the rear end side of the balloon by a two-component urethane adhesive (UR0531;
H. B. (Made by Fuller Inc.)
It was prepared in the same manner as in Example 1 except that the line opaque marker was positioned at the boundary between the taper portion on the trailing end side of the balloon and the straight pipe portion, and the inner diameter of the movement prevention mechanism joint portion of the balloon was 1.25 mm. .

(Comparative Example 1) A comparative example 1 was prepared in the same manner as in Example 1 except that no movement preventing mechanism was provided on the front end side and the rear end side of the balloon.

(Embodiment 5) For the movement preventing mechanism on the front and rear ends of the balloon, the same tube member as that in Embodiment 1 is used, and each has a polyamide elastomer (trade name: PEBAX7033SA01; elf at) on one end.
A tube-shaped member (inner diameter 0.95 mm, outer diameter 2.00 mm) produced by extrusion molding using Ochem)
Was joined by heat welding, the joints were positioned so as to extend to the taper portions on the front end side and the rear end side of the balloon, and the inner diameter of the movement prevention mechanism joint portion of the balloon was set to 2.05 mm. It was prepared in the same manner as in Example 1.

Example 6 A tubular parison (inner diameter 0.4) was prepared by an extrusion molding method using a polyester elastomer (trade name: Perprene S-6001; manufactured by Toyobo Co., Ltd.).
3 mm, outer diameter 0.89 mm), and then using this parison by a biaxial stretch blow molding method, the outer diameter of the straight pipe portion is 3.0 mm, and the inner diameter of the movement prevention mechanism joint portion is 0.95 mm.
A balloon was prepared. Inner tube (inner diameter 0.4
2 mm, outer diameter 0.56 mm) uses high density polyethylene (trade name: HY540; manufactured by Mitsubishi Chemical Corporation), and outer tube (inner diameter 0.71 mm, outer diameter 0.88 mm) uses polyester elastomer (trade name: Perprene S) -60
01; manufactured by Toyobo Co., Ltd.).
The movement preventing mechanism on the balloon tip side was a tubular member (inner diameter: 0.65 mm, outer diameter: 0.79 mm) and was produced by extrusion molding using a polyester elastomer (trade name: Perprene S-3001; manufactured by Toyobo Co., Ltd.). The movement prevention mechanism on the rear end side of the balloon has a tubular member (inner diameter 0.7
It was made by extrusion molding using a polyester elastomer (trade name: Perprene S-3001; manufactured by Toyobo Co., Ltd.) with a diameter of 1 mm and an outer diameter of 0.88 mm.

The stent was produced by cutting a SUS316L tube (inner diameter 1.80 mm, outer diameter 2.05 mm) into a desired pattern by laser processing and then electrolytically polishing it.

After the movement preventing mechanism on the front end side and the movement preventing mechanism on the rear end side were joined to the balloon by heat welding, the outer tube and the balloon were joined by heat welding. Approximately 180 mm in the circumferential direction on the outer peripheral surface of the outer tube, which is about 200 mm from the joint of the outer tube and the balloon to the rear end side.
The cut portion was produced by cutting. The inner tube was inserted from the cut portion, and the inner tube and the outer tube were arranged in a coaxial double tube shape. At this time, one end of the inner tube is aligned with the cut portion, and the other end is penetrated through the inside of the balloon so that the inner tube is positioned closer to the tip side than the balloon. Adhesive (UR0531, H.B. Full
(manufactured by R Co., Ltd.), and the balloon and the inner tube were joined on the balloon tip side with the same adhesive. At the time of joining, a core material of an arbitrary size coated with a highly lubricious material such as polytetrafluoroethylene was appropriately used in order to secure an inflation lumen. The inner tube was subjected to oxygen plasma treatment as a pretreatment before joining.

While decompressing the inside of the balloon, the balloon was folded into a triset shape (the number of folded wings was 3), and the stent in the deflated state was placed in the straight portion of the balloon.
The heat-shrinkable tube placed on the outer surface of the stent was contracted to bring the stent in the contracted state into close contact with the outer surface of the balloon. Finally, the heat-shrinkable tube removed was used as a sample of the tip portion of the high-speed exchange-type stent delivery catheter.

(Example 7) The procedure of Example 6 was repeated except that the outer tube was used as the movement preventing mechanism on the rear end side of the balloon.

(Embodiment 8) The movement preventing mechanism on the balloon tip side uses the same tubular member as in Embodiment 5, the outer diameter of one end is expanded to 1.20 mm, and the expanded portion is tapered on the balloon tip side. Extended to the department. The movement preventing mechanism on the balloon rear end side uses the same tube member as in Example 5, expands the outer diameter of one end to 1.20 mm, and extends the expanded portion to the taper portion on the balloon rear end side, and Example 6 except that the inner diameter of the joint for preventing movement of the balloon was set to 1.25 mm.
Was prepared in the same manner as in.

(Embodiment 9) An X-ray opaque marker (inner diameter: 0.83 mm;
An outer diameter of 0.90 mm, made of platinum) is adhered and fixed using a two-liquid mixed urethane adhesive (UR0531; made by HB Fuller), and the radiopaque marker is tapered on the balloon tip side. It is located at the boundary between the straight pipe and the pipe. In addition, an X-ray opaque marker (inner diameter 0.92 mm, outer diameter 1.00 mm, made of platinum) is attached to the end of the movement prevention mechanism on the rear end side of the balloon by a two-component urethane adhesive (UR0531;
H. B. (Made by Fuller Inc.)
It was prepared in the same manner as in Example 6 except that the line opaque marker was located at the boundary between the taper portion on the rear end side of the balloon and the straight pipe portion, and the inner diameter of the movement prevention mechanism joint portion of the balloon was 1.25 mm. .

(Comparative Example 2) A comparative example 2 was prepared in the same manner as in Example 6 except that no movement preventing mechanism was provided on the front end side and the rear end side of the balloon.

(Embodiment 10) For the movement preventing mechanism on the front and rear ends of the balloon, the same tube member as in Embodiment 5 is used, and each has a polyester elastomer (trade name: Perprene S-3001; Toyobo) on one end. A tube-shaped member (inner diameter 0.95 mm, outer diameter 2.00 mm) produced by extrusion molding using the same is joined by heat welding, and the joined portions are formed on the taper portions of the front end side and the rear end side of the balloon. Example 6 except that the balloon was positioned so as to extend and the inner diameter of the movement prevention mechanism joint portion of the balloon was 2.05 mm.
Was prepared in the same manner as in.

(Evaluation of Stent Transfer Prevention Property) The sample was moved back and forth while gripping the stent portion of the prepared sample, and qualitatively evaluated whether or not the stent could be easily moved or dropped. .

(Evaluation of Insertion Property into Body) The operability of inserting the prepared sample into the body was evaluated. For evaluation, a system in which a guide catheter 12, a hemostack valve 13, and a guide wire 14 were arranged as shown in FIG. 14 and water was circulated inside the guide catheter 12 and the hemostack valve 13 was used. The sample was inserted from the inlet of the hemostack valve 13 and the operability during insertion was evaluated. In this evaluation, ZumaI is used as the guide catheter 12.
I (7Fr, JL4.0, manufactured by Medtronic AVE) was used as a guide wire 14 for BMW (0.01).
4 ", manufactured by Guidant) was used.

(Evaluation result)

[0066]

[Table 1]

In Examples 1 to 10 according to the present invention, the stent was not moved or dropped, and the object of the present invention could be achieved. In Comparative Examples 1 and 2, it was revealed that the stent was apt to move or fall off, and was unsuitable as a stent delivery catheter. Also,
In Examples 5 and 10, since the folded outer diameter of the taper portion of the balloon is slightly large, resistance is generated in the guide catheter during insertion into the body and the operability is slightly reduced, but the movement or removal of the stent is effective. It can be suppressed.

[0068]

As described above, according to the stent delivery catheter of the present invention, the stent delivery catheter has a hub having a front end portion and a rear end portion, and the rear end portion having a port for supplying a pressure fluid. The distal end portion includes a tapered portion having a truncated cone shape and a straight tubular portion having a cylindrical shape, has a collapsible balloon, and the stent is disposed in a contracted state on the outer surface of the folded balloon. And an inner tube that defines a guide wire lumen extends inside the balloon, and a mechanism for preventing movement of the stent fixed to only the inner surface of the balloon in the length direction of the stent delivery catheter is provided. Therefore, the stent can be placed with good operability even if it is a bent stenosis, and the stent does not drop or move. It is possible to provide a stent delivery catheter which does not.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of an over-the-wire type of a general balloon catheter.

FIG. 2 is a schematic perspective view of a rapid exchange type of a general balloon catheter.

FIG. 3 is a schematic side view showing a cross section of a coaxial structure of a general balloon catheter.

FIG. 4 is a cross-sectional view taken along the line A-A ′ of FIG.

FIG. 5 is a schematic side view showing a cross section of a biaxial structure of a general balloon catheter.

6 is a cross-sectional view taken along the line B-B ′ of FIG.

FIG. 7 is a schematic side view of the stent delivery catheter according to the present invention in which a movement prevention mechanism is provided on the front end side and the rear end side of the balloon.

FIG. 8 is a schematic side view of the stent delivery catheter according to the present invention when the movement preventing mechanism on the rear end side of the balloon is an outer tube.

FIG. 9 is a stent delivery catheter according to the present invention, in which a movement prevention mechanism is provided on the front end side and the rear end side of the balloon, and the outer diameter of the movement prevention mechanism of the portion extending inside the balloon is larger than the outer diameter of the fixed portion. It is a schematic side view at the time of also being large.

FIG. 10 is a schematic side view showing another embodiment of FIG.

FIG. 11 is a schematic side view of the stent delivery catheter according to the present invention in which a movement preventing mechanism is provided on the front end side and the rear end side of the balloon, and a radiopaque marker is provided on a portion extending inside the balloon. It is a figure.

FIG. 12 is a schematic perspective view of a case where the balloon shown in FIG. 3 is folded and a stent is arranged.

13 is a schematic perspective view when the balloon shown in FIG. 7 is folded and a stent is arranged.

FIG. 14 is a schematic diagram of an evaluation system for evaluating insertion characteristics into the body.

[Explanation of symbols]

1 Balloon 1A Straight pipe part 1B Tapered part 2 Outer tube 3 Inner tube 4 X-ray impermeable marker 5 Guide wire lumen 6 Inflation lumen 7 Dual lumen tube 8 Movement prevention means 8A Outer diameter of movement prevention means extending inside the balloon (D
2) 8B Outer diameter (D1) of the movement preventing means at the fixed portion with the balloon 9 Hub 10 Guide wire inlet portion 11 Stent 12 Guide catheter 13 Hemostack valve 14 Guide wire 15 Stent delivery catheter tip sample

Claims (10)

[Claims] 1. A stent delivery catheter for delivering a stent for treating a stenosis part in a living body to the stenosis part, wherein the stent delivery catheter has a front end portion and a rear end portion, and the rear end portion has Has a hub having a port for supplying pressure fluid, and has a truncated cone-shaped taper portion and a cylindrical straight tube portion at the tip end thereof, and has a foldable balloon and the outer surface of the folded balloon. The stent is disposed in a contracted state, and an inner tube that defines a guide wire lumen extends inside the balloon, and the stent delivery catheter of the stent fixed only to the inner surface of the balloon. A stent delivery catheter comprising a mechanism for preventing movement in the length direction. 2. The stent delivery catheter according to claim 1, wherein the movement preventing mechanism is provided on a front end side and a rear end side of the balloon. 3. The stent delivery catheter according to claim 1, wherein the movement preventing mechanism is a tubular member. 4. The movement prevention mechanism extends only to a taper portion of the balloon, and does not extend to a straight pipe portion of the balloon. Stent delivery catheter. 5. When the outer diameter of the movement prevention mechanism in the fixing portion of the movement prevention mechanism and the balloon is D1 and the outer diameter of the movement prevention mechanism of the portion extending inside the balloon is D2, 1 The stent delivery catheter according to claim 4, wherein ≦ (D2 / D1). 6. When the outer diameter of the movement preventing mechanism in the fixed portion of the movement preventing mechanism and the balloon is D1 and the outer diameter of the movement preventing mechanism of the portion extending inside the balloon is D2, 1 The stent delivery catheter according to claim 4, wherein ≦ (D2 / D1) ≦ 2. 7. The stent delivery catheter according to claim 1, wherein the movement prevention mechanism is made of a material that can be fused with the balloon. 8. The stent delivery catheter according to claim 7, wherein the migration preventing mechanism is made of polyamide or polyamide elastomer, and the balloon is made of polyamide elastomer or a blend material of polyamide elastomers. 9. The stent delivery catheter according to claim 7, wherein the migration preventing mechanism is made of polyester or polyester elastomer, and the balloon is made of polyester elastomer or a blend material of polyester elastomers. 10. The stent delivery catheter according to claim 1, wherein a marker having radiopacity is attached to the movement prevention mechanism.