JP3488351B2 - Vasodilator - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vasodilator for dilating a stenosis and improving blood flow on the peripheral side of the stenosis in order to treat an intravascular stenosis, in other words, a vasodilator.
The present invention relates to a vasodilator catheter.

[0002]

2. Description of the Related Art With the rise of microcatheters, it has become possible to perform treatment and diagnosis in microvessels or blood vessels, which has been impossible with conventional catheters. Examples of the microcatheter include a percutaneous transluminal coronary angioplasty catheter used for myocardial infarction or angina (hereinafter referred to as PTCA dilatation catheter). The general structure of this PTCA dilatation catheter is
It is composed of an outer tube having an expansion lumen, an inner tube having a guide wire lumen, an expansion body attached near the tips of the inner tube and the outer tube, and a hub attached to the proximal ends of the inner tube and the outer tube. Since the catheter tube that constitutes the PTCA dilatation catheter requires at least two lumens as described above, a plastic tube having an axial cross-section with a different axis, such as a double lumen, or a coaxial structure using a coaxial catheter tube is used. It is common to use the plastic tube of. A feature of the PTCA dilatation catheter composed of the hetero-axial catheter tube is that it has good vascular pushability. However, the operability of the guide wire is poor, and it is not suitable for reducing the diameter of the catheter tube. Therefore, the mainstream of the PTCA dilatation catheter in recent years has a coaxial structure with a coaxial catheter tube. Then, as one having improved running property and pushing property in the blood vessel, for example, E
P0405831B1, JP-A-5-137793 and JP-A-3-51059.

[0003]

[Problems to be Solved by the Invention] EP0405831B
1 or the one disclosed in JP-A-5-137793,
The inner tube and the outer tube are adhered over a considerable length from the position far away from the balloon to the base end of the balloon to narrow the flow path for balloon expansion. You have to go through a narrowed channel from the front. Therefore, there is a problem that the flow path of the expansion liquid necessary for expanding the expansion body is obstructed and the expansion / contraction time of the expansion body is delayed. In addition, Japanese Patent Laid-Open No. 3-
No. 51059 has a structure in which an inner tube and an outer tube are joined inside a balloon by a ring-shaped spacer, and an opening is formed in a wall of the outer tube in a direction perpendicular to the long axis of the shaft. There is. For this reason, the liquid for inflating the balloon is injected and discharged through this narrow opening, and it is difficult for the liquid to flow smoothly, and there is a problem that the inflation and deflation time of the balloon is long.

[0004] Therefore, an object of the present invention is to have very little interruption of the flow path of the expansion liquid or obstruction of the liquid flow into the expansion body, and the expansion and contraction time of the expansion body is short (expansion / contraction time response is good). In addition, by fixing the inner tube and the outer tube, a vasodilator is provided which has a good pushability in the blood vessel (running property in the blood vessel).

[0005]

[Means for Solving the Problems] What achieves the above object is to provide an inner tube having a first lumen and a tip provided coaxially with the inner tube and retracted by a predetermined length from the tip of the inner tube. An outer tube forming a second lumen between the outer tube and the outer surface of the inner tube, and a distal end portion and a proximal end portion, the proximal end portion being attached to the outer pipe, and the distal end portion being A foldable expansion body attached to the inner pipe, in which the second lumen communicates with the inside, and a first opening provided in a proximal end portion of the inner pipe communicating with the first lumen. A second opening communicating with the second lumen, the second opening being provided at a base end of the outer tube, the outer tube having a projecting section projecting into the expandable body. Is a cutout portion that extends a predetermined distance from the distal end to the proximal end side, and the outer tube and the inner portion that are provided in the portion where the cutout portion is formed. Has a fixed portion and, at the rear end portion of the cutout portion of the projecting portion, the internal of the extension body second
It is a vasodilator that communicates with the lumen.

The fixing portion between the outer tube and the inner tube is heat-shrinkable so that, for example, a part of the cutout portion of the protruding portion of the outer tube is encapsulated together with the inner pipe portion located inside the cutout portion. It is formed by a tube. The fixed portion between the outer pipe and the inner pipe is formed, for example, by welding or adhering the cutout portion of the protruding portion of the outer pipe and the inner pipe portion located inside the cutout portion. Further, it is preferable to have a linear rigidity imparting body extending in the axial direction provided in the second lumen. Furthermore, the outer tube includes a main body side outer tube and a tip side outer tube, the main body side outer tube includes an intruding portion that has entered the proximal end portion of the distal end side outer tube, the intruding portion, It is preferable that slits or a large number of pores are provided. The cutout portion extends from the tip of the protruding portion to the rear end side for a predetermined length, and is 1/5 to 4/5 of the arc.
It is preferably formed by excising.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION A vasodilator according to the present invention will be described below with reference to the drawings. FIG. 1 is an external view of an embodiment of the vasodilator according to the present invention, FIG. 2 is an enlarged cross-sectional view of a distal end portion of the vasodilator shown in FIG. 1, and FIG.
FIG. 4 is an enlarged partial cutaway cross-sectional view of the vicinity of the joint between the distal outer tube and the proximal outer tube of the vasodilator shown in FIG. 1, and FIG.
FIG. 6 is a perspective view of a fixing portion between an inner tube and an outer tube in the vasodilator shown in FIG. 5, FIG. 5 is an enlarged partial cutaway sectional view of a main body of the vasodilator shown in FIG. 1, and FIG. A- in FIG.
It is an A line sectional view.

The vasodilator (vasodilator catheter) 1 of the present invention comprises an inner tube 2 having a first lumen 5 and an inner tube 2.
An outer tube 3 which is provided coaxially with the outer tube 3 having a tip at a position retracted from the tip of the inner tube 2 by a predetermined length and which forms a second lumen 6 between the outer tube 3 and the outer surface of the inner tube 2, a tip portion 41, and Proximal end 42
And a proximal end 42 is attached to the outer tube 3 and a distal end 4
1 is attached to the inner tube 2, the second lumen 6 and the inner 4
a collapsible expansion body 4 communicating with a, a first opening 9 provided at the base end of the inner tube 2 communicating with the first lumen 5, and an outer tube communicating with the second lumen 6. And a second opening portion 11 provided at the base end portion of No. 3. Furthermore, the outer tube 3 has a protrusion 30 that protrudes into the expansion body 4, and the protrusion 30 has a notch 31 that extends a predetermined distance from the distal end toward the proximal side.
And a fixing portion for fixing the outer tube 3 and the inner tube 2 provided in a portion where the cutout portion 31 is formed, and at the rear end portion (communication portion 33) of the cutout portion 31 of the projecting portion 30, the expansion body 4 is provided. The interior 4a of the and the second lumen 6 communicate with each other.

A description will be given below with reference to the drawings. As shown in FIG. 1, the vasodilator 1 of the present invention includes a vasodilator body 10 having an inner tube 2, an outer tube 3 and an expander 4, and a branch hub 12. Further, the vasodilator main body 10 includes a tip portion 10a and a body portion 10b each having a small diameter. The vasodilator 1 is provided with a fixing portion 32 that fixes the inner tube 2 and the outer tube 3 to the tip of the outer tube 3.

The inner tube 2 is a tube body having a first lumen 5 for inserting a guide wire therein.
The inner tube 2 has a length of 300 to 2000 mm, more preferably 300 to 1500 mm, and an outer diameter of 0.1 to
1.0 mm, more preferably 0.3 to 0.7 mm, wall thickness 10 to 150 μm, more preferably 20 to 100 μm
m. As the material forming the inner tube 2, a material having flexibility to some extent is used. For example, polyolefin (for example, polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more thereof), or a crosslinked product thereof, polyvinyl chloride, polyamide, Polymer materials such as polyamide elastomer, polyester, polyester elastomer, polyurethane, polyurethane elastomer, polyimide and fluororesin, or a mixture thereof can be used.

The inner tube 2 is inserted into the outer tube 3, and the tip of the inner tube 2 projects from the outer tube 3. As shown in FIG. 2, the outer surface of the inner tube 2 and the inner surface of the outer tube 3 form a second lumen 6, which has a sufficient volume. In this embodiment, as shown in FIG. 5, the inner tube 2 has a small diameter on the tip side and a larger diameter on the body side than the tip side. Specifically, as shown in FIG. 5, a taper portion that expands in diameter is provided at a position slightly closer to the base end side than the joint portion between the main body outer tube and the tip outer tube, which will be described later. The inner pipe 2 has an outer diameter of 0.30 on the tip side of the inner pipe.
It is 2.00 mm, preferably 0.40 to 1.80 mm, and the outer diameter of the inner tube body side is 0.40 to 2.50 mm, preferably 0.55 to 2.40 mm. As such different-diameter inner pipes, the inner pipe tip side and the inner pipe base end side are individually created and joined, those that have been subjected to secondary processing such as withdrawal, and the diameter of the tip side by extrusion molding. Any one formed by making it smaller than the main body side diameter may be used.

The outer tube 3 is a tube body in which the inner tube 2 is inserted and the tip of which is located slightly behind the tip of the inner tube 2. As shown in FIGS. 2, 3, 5, and 13, the inner surface of the outer tube 3 and the outer surface of the inner tube 2 form a second lumen 6. Further, the tip portion of the outer tube 3 forms a fixing portion 32 with the inner tube 2 and a communication portion 33 between the expansion body 4 and the second lumen, so as to be described later, a protrusion protruding into the expansion body 4. It is part 30. The outer tube 3 has a length of 300 to 2000 mm, more preferably
300 to 1500 mm, outer diameter is 0.5 to 1.5 mm,
More preferably, 0.7 to 1.1 mm, wall thickness 25 to 20
The thickness is 0 μm, more preferably 50 to 100 μm.

As the material forming the outer tube 3, a material having flexibility to some extent is used. For example, polyolefin (for example, polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer, or a mixture of two or more thereof), or a crosslinked product thereof, polyvinyl chloride, polyamide, Polymeric materials such as polyamide elastomers, polyesters, polyester elastomers, polyurethanes, polyurethane elastomers, fluororesins and polyimides, or mixtures thereof can be used.

In the vasodilator 1 of this embodiment, the outer tube 3
As shown in FIG. 3, the front end side outer pipe 3a and the main body side outer pipe 3 are
It is formed by b, and both are joined. The tip-side outer pipe 3a is tapered at a portion closer to the tip than the joint portion with the main body-side outer pipe 3b, and the tip side is thinner than the tapered portion.

In this way, when the joined body of the main body side outer tube 3b and the tip side outer tube 3a is used as the outer tube 3, the forming materials may be different. For example, a highly rigid material (for example, a polyimide resin) is used for the main body side outer tube 3b, and a material that is more flexible than the material for forming the main body side outer tube 3b (for example, a polyamide resin) as the tip side outer tube 3a. Is preferably used. The outer diameter of the tip side outer tube 3a at the small diameter portion is 0.50 to 1.5 mm, preferably 0.60 to 1.1 mm. Further, the outer diameters of the base end portion of the distal end side outer tube 3a and the main body side outer tube 3b are 0.75 to 1.
It is 5 mm, preferably 0.9 to 1.1 mm. Then, as shown in FIG. 3, the tip end portion of the main body side outer pipe 3b has an outer diameter substantially equal to the inner diameter of the tip end side outer pipe 3a, and the intrusion portion 34 that has entered the base end portion of the tip end outer pipe 3a. (In other words, the insertion part). Then, in the intrusion part 34,
A slit 35 is provided. Note that a large number of pores may be formed instead of the slits 35.

In this embodiment, the slit 35 has a spiral shape. Further, the slit 35 has a start end at the tip of the intrusion part 34 or at a position slightly proximal to the tip, and has an end at a position slightly distal to the base end of the intrusion part 34. In other words, the base end portion of the intrusion portion 34 has a slit 35 and a portion 36 in which no pore is formed,
In the slit or the pore-free portion 36, the tip-side outer tube 3a and the body-side outer tube 3b are fixed. On the contrary, in the slit or the pore forming portion, the outer tube 3a on the tip side is formed.
The main body side outer tube 3b is not fixed.

The length of the intrusion part 34 is 10 to 250.
It is preferably about mm, and particularly preferably about 10 to 50 mm. The length of the slit 35 or the pore forming portion is preferably about 5 to 245 mm, and particularly 5 to 245 mm.
It is preferably about 45 mm. Further, the length of the slit 35 or the non-pore forming portion 36 is preferably about 3 to 20 mm, and particularly preferably about 3 to 10 mm.

Since the width of the slit 35 is determined in consideration of the diameter of the outer tube 3 and the like, it is not uniform. The width of the slit 35 is 1.0 mm to 2.0 mm at the tip.
The degree is preferably 0.1 mm to 0.5 mm at the base end.
Is preferred. The width of the slit 35 is preferably about 1/2 to 2 times the outer diameter of the outer tube 3. Within the above range, the outer tube 3 is sufficiently flexible and the outer tube 3 does not break during use.

Further, the pitch of the slits 35 may be the same throughout, or may be partially or stepwise changed. When changing the pitch, it is preferable that the pitch at the base end is longer than that at the tip. And, in the middle portion between the tip end portion and the base end portion, it is preferable that the width of the slit 35 is the middle of the two or the width is gradually narrowed. Further, the shape of the slit 35 may be such that the width of the slit 35 is wide at the distal end portion and narrow at the proximal end portion. By doing so, the tip portion of the main body side outer tube 3b becomes more natural because the tip portion of the main body side outer tube 3b becomes more flexible, and the operability of the vasodilator is further improved.

The size of the pores provided in place of the slits 35 is not uniform because it is determined in consideration of the number of pores, the outer diameter of the outer tube 3 and the like. As the pore size,
It is preferably about 0.1 mm to 0.4 mm, more preferably 0.2 mm to 0.3 mm. The hole diameter is preferably about 1/10 to 1/3 of the outer diameter of the outer tube 3. Within the above range, the outer tube 3 is sufficiently flexible and is in use.
Does not break. The distance between the pores is
It is preferably about 0.1 mm to 0.5 mm. Within the above range, the outer tube 3 is sufficiently flexible and the outer tube 3 does not break during use.

It is preferable that the number of pores on the side of the leading end of the intrusion portion 34 is larger than that on the side of the base end portion. By doing so, since it becomes flexible toward the distal end portion, there is no abrupt change in physical properties, the entry portion 34 of the outer tube of the main body portion is naturally curved, and the operability of the vasodilator is further improved. To do.
Further, it is preferable that the number of pores gradually increases from the base end side of the intrusion portion 34 toward the tip end side. By doing so, since it gradually becomes softer toward the distal end portion, the bending of the intrusion portion 34 becomes more natural, and the operability of the vasodilator is further improved. In this way, when the pore distribution changes, the distance between the pores at the tip of the intrusion part 34 is about 0.1 to 0.2 mm, and at the base end is 0.
3 mm to 0.5 mm is preferable, and in particular, in the middle portion between the tip end portion and the base end portion, it is preferable that the distance between the pores is about the middle of the two or gradually changes. Further, instead of changing the pore size distribution, the pore size of the pore itself may be larger on the front end side of the inner tube 2 than on the base end side.

The shape of the pores does not have to be a perfect circle, but may be an ellipse, for example, an ellipse elongated in the circumferential direction or the axial direction of the inner tube 2 and a polygon (for example, a quadrangle or a pentagon). The area of one pore is 0.007 mm ² ~
It is preferably about 0.13 mm ² , and the distance between the pores is preferably about 0.1 to 0.5 mm.

As shown in FIGS. 2 and 4, the outer tube 3 has a projecting portion 30 which projects into the expansion body 4, and the projecting portion 30 has a notch extending from the distal end toward the base end side by a predetermined distance. Part 3
1 is provided with a fixing portion 32 of the outer tube 3 and the inner tube 2 in the portion where the cutout portion 31 is formed, and at the rear end portion of the cutout portion 31 of the outer pipe 3, the inside 4a of the expansion body 4 and Second lumen 6
And are in communication. Thus, the tip of the outer tube 3 is the inner tube 2
Since it is fixed to the vasodilator, the vasodilator has good pushability in blood vessels (running property in blood vessels), and
At the rear end portion of the cutout portion 31 of the outer tube 3, since the interior 4a of the expansion body 4 and the second lumen 6 communicate with each other, the opening area of the communication portion 33 between the expansion body 4 and the second lumen 6 Is
There is no great difference from the cross-sectional area of the second lumen 6, and therefore, the inflow and outflow of the liquid into the expansion body 4 are also good.

As shown in FIGS. 4 and 6, the cutout portion 31 is a cutout portion having a predetermined length from the front end of the protruding portion 30 to the rear end side and having a ring shape with a half section. As described above, even when the outer tube 3 projects into the expansion body 4, since the distal end portion is cut out, it is less likely to cause an obstacle when the outer tube 3 is inserted into the narrowed portion. Specifically, the notch 31 is the protrusion 3
From the tip of 0 to the axial direction for a predetermined length and 5/10 of the arc
It is formed by excising 0 to 95/100. Preferably, 1/5 to 4/5 of the arc is excised, particularly preferably about half to about 2/3. By forming such a cutout portion 31, the cutout portion forming portion has a gutter shape with an upper opening.

Degree of fixation (area) between the outer pipe 3 and the inner pipe 2
It is preferable that 5% or more of the outer tube 3 in the circumferential direction is fixed to the outer tube 3 in the portion where the notch 31 is formed. In order to achieve such fixation, the length of the arc inside the notch forming portion of the outer tube 3 needs to be 5% or more of the outer circumference of the inner tube 2. Even if the length of the arc inside the cutout forming portion of the outer tube 3 is 5% or more of the outer circumference of the inner tube 2, it is possible to fix about 5% by fixing part of it. it can. More preferably, the outer tube 3
The degree of fixation between the inner tube 2 and the inner tube 2 is that 20% to 80% of the inner tube 2 in the circumferential direction is fixed to the outer tube 3 in the portion where the notch 31 of the outer tube is formed. For this purpose, the length of the arc inside the cutout forming portion of the outer tube 3 needs to be 20% to 80% of the outer circumference of the inner tube 2. Particularly preferably, 40% to 68% of the inner tube 2 in the circumferential direction is fixed to the outer tube 3. The length of the protrusion 30 of the outer tube 3 into the expansion body 4 is preferably about 1 to 20 mm.

In the embodiment shown in FIGS. 2 and 4, the outer tube 3
The inner tube 2 and the inner tube 2 are fixed to each other by the cutout 31 of the protrusion 30 of the outer tube 3.
A part (specifically, a tip end) of the inner tube 2 is covered with a heat-shrinkable tube 37 together with a portion of the inner tube 2 located in the cutout 31, and the tube 37 is heat-shrinked and fixed. Particularly, in this embodiment, the fixing portion 32 is formed at the tip of the outer tube 3, and the fixing portion 32 does not reach the rear end of the cutout portion 31. That is, the non-fixed portion 38 is formed between the rear end of the fixed portion 32 and the rear end of the cutout portion 31. By forming such a non-fixed portion 38, the cutout portion 31
Communication part 3 between expansion body 4 and second lumen formed by the rear end of
3 becomes wider and the inflow and outflow of the expansion liquid becomes better. In this embodiment, as shown in FIGS. 2 and 4, the heat-shrinkable tube 37 has a distal end encapsulating only the inner tube 2 and a rear end near the center of the notch 31 (to the rear end of the notch 31). There is no position). The fixing portion 32 of the inner pipe 2 and the outer pipe 3 is only a portion where the inner pipe 2, the outer pipe 3 and the tube 37 overlap each other, and is not fixed between the rear end of the tube 37 and the rear end of the cutout portion 31. The part 38 is formed.

The heat shrinkable tube 37 is made of a stretchable material and has an inner diameter slightly smaller than the outer diameter of the inner tube 2.
It can be created by expanding this in the radial direction. As the forming material, polyolefin such as polyethylene and polypropylene, EAA (ethylene-acrylic acid copolymer),
EVA (ethylene-vinyl acetate copolymer) or the like can be used. The heat-shrinkable tube 37 is coated so that the tip of the outer tube 3 is near the center in the axial direction, and is heated by applying hot air to shrink the outer tube 3 and the tip of the outer tube 3 and its vicinity. The outer tube 3 is in close contact with the outer surface of the inner tube 2, and the tip of the outer tube 3 is fixed to the inner tube 2. The length of the heat-shrinkable tube 37 with the outer tube 3 fixed is preferably about 1 to 20 mm. Further, as shown in FIG. 7, the cutout portion 31 may be cut out obliquely so that the cross-sectional area decreases toward the tip of the outer tube 3.

Further, the fixing of the outer tube 3 to the inner tube 2 is not limited to the one using the heat-shrinkable tube 37 as described above, and the adhesive member 39 is used to connect the tip of the outer tube 3 to the inner tube. Two
Interspersed with the adhesive material and welding (fusing) this adhesive material,
It can also be performed by so-called adhesion. Adhesive member 39
As an example, there is a method of using a tube-shaped one having an inner diameter substantially equal to the outer diameter of the inner tube 2, inserting this tube between the tip of the outer tube 3 and the inner tube 2, and heating and welding. A perspective view of this case is shown in FIG. Further, FIG. 9 is a sectional view of the fixing portion 32 in this case.

As the adhesive member 39, for example, a gutter-shaped member may be used. The cross section of the fixing portion 32 when this trough-shaped member is inserted between the tip of the outer tube 3 and the inner tube 2 and heated and welded is as shown in FIG. Examples of the material for forming the adhesive member include modified polyolefins (for example, ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene- Ethyl acrylate-maleic anhydride copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ionomer, MAH-g
-Polyolefin etc. can be used.

Further, the fixing of the outer tube 3 to the inner tube 2 is not limited to the above-mentioned method, and may be performed by a method such as an adhesive or fusion. As such a fixing method, when the outer tube 3 and the inner tube 2 are made of compatible materials, they can be fixed by solvent bonding or fusion bonding. In this case or when fixed with an adhesive, the cross-sectional shape of the fixing portion 32 is as shown in FIG. As the adhesive, cyanoacrylate-based, acrylic-based, epoxy-based, urethane-based, hot-melt-based, elastomer-based, thermoplastic resin-based, etc. can be used.

The expansion body 4 is a foldable body,
In a state where it is not expanded, it can be folded into the outer periphery of the inner tube 2. And the extension body 4
Has a substantially cylindrical portion having substantially the same diameter, at least a part of which has a substantially cylindrical shape in the expanded state so that the narrowed portion of the blood vessel can be easily expanded. The above-mentioned substantially cylindrical portion does not have to be a perfect cylinder, and may be a polygonal prism.
In the expansion body 4, the tip end portion 41 is fixed to the tip end of the inner tube 2, and the base end portion 42 of the expansion body 4 is located at a position slightly proximal to the tip end of the outer tube 3 (specifically, the protruding portion 30). Is fixed to the rear end of the notch 31 or a portion of the vicinity thereof to a predetermined length). Further, the inside 4 a of the expansion body 4 is in communication with the second lumen 6 formed between the outer pipe 3 and the inner pipe 2 by the communication portion 33 formed by the rear end of the cutout portion 31. As the size of the expansion body 4, the outer diameter of the cylindrical portion when expanded is 1.0 to 10 mm, preferably 1.0 to 5.0 m.
m, the length is 5 to 50 mm, preferably 10 to 40
The length of the entire expansion body 4 is 10 to 70 mm, preferably 15 to 60 mm.

The material of the expander 4 is preferably one that can expand the stenosis of the blood vessel and has a certain degree of plasticity, such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer. Polymers such as coalesces, polyolefins such as ionomers, and cross-linked or partially cross-linked products thereof, polyesters such as polyethylene terephthalate, polyester elastomers, polyvinyl chloride, polyurethane, polyurethane elastomers, polyphenylene sulfides, polyamides, polyamide elastomers and fluororesins. , Silicone rubber, latex rubber, etc. can be used. Also, a laminated film in which these polymer materials are appropriately laminated can be used.

Then, as shown in FIG. 2, it is preferable to provide a marker 15 on the outer surface of the inner tube 2 in the central portion of the cylindrical portion of the expansion body 4. Further, the second marker 1 is provided on the outer surface of the inner tube 2 located at the base end of the cylindrical portion.
6 may be provided. Furthermore, without providing in the central part,
Two may be provided on the outer surface of the inner tube 2 at the portions located at both ends of the cylindrical portion of the expansion body 4. The marker is preferably formed by a coil spring or a ring. As a material for forming the marker, a material having a high X-ray contrast property, for example, Pt, Pt alloy, W, W alloy, Au, Au alloy, I
It is preferable to use r, Ir alloy, Ag, Ag alloy or the like.

Between the inner pipe 2 and the outer pipe 3 (inside the second lumen 6), a linear rigidity imparting body 13 is provided as shown in FIGS. 2, 3, 5 and 13. Has been inserted. The rigidity imparting body 13 prevents extreme bending of the vasodilator main body 10 at a bent portion without reducing the flexibility of the vasodilator, and facilitates pushing of the distal end of the vasodilator. . The linear body is preferably a metal wire, and an elastic metal such as stainless steel having a wire diameter of 0.05 to 1.50 mm, preferably 0.10 to 1.00 mm, a superelastic alloy, and the like are particularly preferable. Is a high-strength stainless steel for spring, Ni / Ti alloy wire with superelasticity.

As shown in FIGS. 2, 3 and 12, the tip of the rigidity imparting body 13 has a smaller diameter than the other portions by a method such as polishing. In this embodiment, the tip of the small-diameter portion extends to the vicinity of the tip portion 3b of the main body outer tube 3. The tip of the small diameter portion may extend to the vicinity of the tip of the outer tube 3. The tip of the rigidity imparting body 13 is not fixed to either the outer tube 3 or the inner tube 2. The outer diameter of the small diameter portion of the rigidity imparting body 13 is preferably about 1/5 to 1/10 of the outer diameter on the base end side. Furthermore, the rigidity imparting body 13 preferably has a higher rigidity on the base side than on the tip side. This can be achieved, for example, by using the rigidity imparting body 13 having a larger cross-sectional area on the base side than on the tip side. Further, since the tip end portion of the rigidity imparting body 13 is more flexible and the main body portion has high rigidity,
After cold working the metal wire used for the rigidity imparting body 13,
It may be annealed with a temperature gradient that is high on the tip side and low on the body side. Further, the rigidity imparting body 13 may be formed by a twisted wire in which several thin metal wires are twisted together.

The base end of the rigidity imparting body 13 is fixed to the base end of the inner tube 2, as shown in FIG. In addition, you may fix to the base end of the outer tube 3. Since the rigidity imparting body 13 is not fixed except the base end, the rigidity imparting body 13 can move within the lumen. Such a rigidity imparting body 1
By providing 3, the vasodilator main body 10 is prevented from meandering in the blood vessel. For this reason, the pushing force applied at the base end of the vasodilator body 10 is not buffered at the meandering portion, and the pushing force applied at the base end of the vasodilator body 10 is expanded. It can be reliably transmitted to the tip of the device. Therefore, the operability of the vasodilator, in particular, the work of pushing the distal end portion (the portion to which the expansion body 4 is attached) of the vasodilator into the intravascular stenosis is facilitated, and the vascular stenosis of a high degree (Complete block)
Also, it becomes possible to insert the tip portion of the vasodilator.

Next, the base end portion of the vasodilator 1 of the present invention will be described with reference to FIG. In the vasodilator 1 of this embodiment, the branch hub 12 is fixed to the base end.
The branch hub 12 has a first opening 9 communicating with the first lumen 5 and forming a guide wire port, and communicating with the inner tube hub 22 fixed to the inner tube 2 and the second lumen 6. It has a second opening 11 that forms an injection port, and is composed of an outer tube hub 23 fixed to the outer tube 3. The outer pipe hub 23 and the inner pipe hub 22 are fixed to each other. As a material for forming the branch hub 12, thermoplastic resins such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer can be preferably used.

In this embodiment, a bend preventing tube 50 is provided at the end of the outer tube 3. The bending prevention tube 50 has heat shrinkability, and is formed such that the inner diameter after heat shrinkage is slightly smaller than the outer diameter of the outer tube 3, and the tube 50 thus formed is used as the outer tube 3 It is attached by being fitted to the end portion of and being heated (for example, hot air is blown) and contracted. Then, the bending prevention tube 50 is attached to the outer tube hub 23 by a stopper pin 52.
It is fixed by. In this fixing method, a retaining pin 52 having an enlarged rear end portion is inserted into the rear end of the outer pipe 3 such that the outer diameter of the portion other than the rear end portion is substantially equal to the inner diameter of the outer pipe 3, and the outer pipe 3 is fixed to the rear end. It is carried out by inserting from the tip into the outer tube hub 23 and pushing the projection 54 provided on the inner surface of the outer tube hub 23 until the rear end portion of the stop pin 52 is crossed. Further, the outer tube hub 23 and the bending prevention tube 5
An adhesive may be applied to the contact surface with 0 to fix it. Materials for forming the outer tube hub include polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-
Thermoplastic resins such as butylene-styrene copolymer can be preferably used.

A bend preventing tube 60 is provided at the end of the inner tube 2. The tube 60 is heat-shrinkable and is formed so that the inner diameter after heat shrinking is slightly smaller than the outer diameter of the inner tube 2. It can be easily attached by fitting it on the substrate and heating (for example, applying hot air) to shrink it. Then, the rigidity imparting body 1
The base end portion of 3 is fixed to the outer surface of the inner tube 2 by the contraction tube 60. The inner tube 2 to which the bending prevention tube 60 is attached is fixed to the inner tube hub 22. In this fixing method, the outer diameter of the portion other than the rear end portion is substantially equal to the inner diameter of the inner pipe 2 at the rear end of the inner pipe 2, and a retaining pin 62 having an enlarged rear end portion is inserted to fix the inner pipe 2 to the rear end. It is carried out by inserting from the tip into the inner pipe hub 22 and pushing the protrusion 64 provided on the inner surface of the inner pipe hub 22 until the rear end portion of the stop pin 62 is crossed. Further, an adhesive may be applied to the contact surface between the inner tube hub 22 and the bending preventing tube 60 to fix the same. As a material for forming the inner tube hub, thermoplastic resins such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer can be preferably used. And
As shown in FIG. 6, the inner pipe hub 22 and the outer pipe hub 23 are fixed. This fixing is performed by inserting the inner tube 2 from the rear end of the outer tube hub 23 attached to the base end of the outer tube 3 and joining it. Further, at this time, by applying an adhesive to the joint portion between the inner pipe hub 22 and the outer pipe hub 23, it is possible to securely fix the both.

The structure of the proximal end of the vasodilator 1 of the present invention is not limited to the above-described one, and the branch hub 12 is not provided, and the first lumen 5 and the second lumen 6 are provided. For example, a tube having a port member forming an opening at the rear end may be liquid-tightly attached to each of them.

The vasodilator of the present invention is not limited to the above-mentioned over-the-wire type, and the first opening is provided in the middle of the vasodilator (on the distal side of the hub). It may be a so-called rapid exchange type. Further, in order to facilitate the insertion of the vasodilator 1 into the blood vessel or the guide catheter, it is desirable to perform a treatment for making the outer surface of the outer tube 3 and the outer surface of the expandable body 4 have lubricity. . Examples of such treatment include poly-2-hydroxyethyl methacrylate, polyhydroxyethyl acrylate,
Hydrophilic coating such as hydroxypropyl cellulose, methyl vinyl ether maleic anhydride copolymer, polyethylene glycol, polyacrylamide, polyvinylpyrrolidone, etc., or coating with a substance exhibiting lubricity such as reactive silicone resin having polydimethylsiloxane in the main chain, or It can be done by fixing.

[0042]

The vasodilator according to the present invention has an inner tube having a first lumen, a coaxially provided inner tube, and a tip at a position retracted by a predetermined length from the tip of the inner tube. An outer tube forming a second lumen between the inner tube and an outer surface of the inner tube, a distal end portion and a proximal end portion, the proximal end portion being attached to the outer pipe, and the distal end portion being attached to the inner pipe. A foldable expander that is attached and that communicates with the second lumen and the interior; a first opening provided at the proximal end of the inner tube that communicates with the first lumen; A second opening provided at a base end portion of the outer tube communicating with the lumen of the outer tube, the outer tube having a projecting section projecting into the expansion body, and the projecting section from the distal end. It has a notch extending toward the base end for a predetermined distance, and a fixing portion for the outer pipe and the inner pipe provided in a portion where the notch is formed. , At the rear end portion of the cutout portion of the projecting portion, and the interior of the expandable member and said second lumen is in communication. In this way, since the tip of the outer tube is fixed to the inner tube, the vasodilator has a good pushability in the blood vessel (running property in the blood vessel), and the rear portion of the cutout portion of the outer tube. Since the inside of the expansion body and the second lumen communicate with each other at the end portion, the opening area of the communication portion between the expansion body and the second lumen does not differ greatly from the cross-sectional area of the second lumen. Liquid inflow and outflow to the expander are also good, expansion and contraction time of the expander is short, and diastolic contraction time responsiveness is good.

[Brief description of drawings]

FIG. 1 is an external view of an embodiment of a vasodilator according to the present invention.

2 is a partially enlarged cross-sectional view of the distal end portion of the blood vessel dilating device shown in FIG.

3 is an enlarged partial cutaway cross-sectional view of a vicinity of a joint between a distal outer tube and a proximal outer tube of the vasodilator shown in FIG.

4 is a perspective view of a fixing portion between an inner tube and an outer tube in the vasodilator shown in FIG.

5 is an enlarged partial cutaway sectional view of a main body of the blood vessel dilating device shown in FIG.

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

FIG. 7 is a perspective view of a fixing portion between an inner tube and an outer tube in a vasodilator according to another embodiment of the present invention.

FIG. 8 is a perspective view of a fixing portion between an inner tube and an outer tube in a vasodilator according to another embodiment of the present invention.

FIG. 9 is a cross-sectional view of a fixing portion between an inner tube and an outer tube of a vasodilator that has the form of fixing the inner tube and the outer tube shown in FIG.

FIG. 10 is a cross-sectional view of a fixing portion between an inner tube and an outer tube in a vasodilator according to another embodiment of the present invention.

FIG. 11 is a cross-sectional view of a fixing portion between an inner tube and an outer tube in a vasodilator according to another embodiment of the present invention.

FIG. 12 is an external view showing an example of a linear rigidity imparting body used in the vasodilator of the present invention.

FIG. 13 is an enlarged cross-sectional view of a proximal end portion of the blood vessel dilating device shown in FIG.

[Explanation of symbols]

1 Vasodilator 5 First lumen 2 inner tube 6 Second lumen 3 outer tube 4 extension 30 protrusion 31 Notch 32 Fixed part 33 Communication part

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A 4-2363 (JP, A) JP-A 3-51059 (JP, A) JP-A 8-733 (JP, A) JP-A 2- 13464 (JP, A) International publication 95/096667 (WO, A1) (58) Fields investigated (Int.Cl. ⁷ , DB name) A61M 25/00-29/04

Claims (6)

(57) [Claims] 1. An inner tube having a first lumen, and an inner tube coaxially provided with the inner tube, having a tip at a position retracted by a predetermined length from the tip of the inner tube, and having an outer surface of the inner tube. An outer tube forming a second lumen, a distal end portion and a proximal end portion, the proximal end portion being attached to the outer pipe, the leading end portion being attached to the inner pipe, and the second lumen. A foldable expansion body that communicates with the inside, a first opening provided at a proximal end of the inner tube that communicates with the first lumen, and the outer tube that communicates with the second lumen. A second opening provided at a base end portion of the outer tube, and the outer tube has a protrusion protruding into the expandable body, and the protrusion has a notch extending from the distal end toward the base end by a predetermined distance. Portion and a fixing portion for fixing the outer pipe and the inner pipe provided in a portion where the cutout portion is formed, the rear portion of the cutout portion of the protrusion At the end portion, the inside of the expandable body and the second lumen communicate with each other, the vasodilator. 2. The fixing portion between the outer pipe and the inner pipe is formed by a heat-shrinkable tube that encloses a part of the cutout portion of the protruding portion of the outer pipe together with the inner pipe portion located inside the cutout portion. The vasodilator according to claim 1, which is formed. 3. The fixing portion between the outer pipe and the inner pipe is formed by welding or adhering a cutout portion of a protruding portion of the outer pipe and an inner pipe portion located inside the cutout portion. Item 1. The vasodilator according to item 1 or 2. 4. The linear rigidity imparting body extending in the axial direction, which is provided in the second lumen.
The vasodilator according to any one of 1. 5. The outer tube includes a body-side outer tube and a tip-side outer tube, and the body-side outer tube includes an intruding portion that has intruded into a base end portion of the tip-side outer tube. The vasodilator according to any one of claims 1 to 4, wherein slits or a large number of pores are provided in the. 6. The cutout portion is formed by cutting a portion from a tip of the protrusion to a rear end side of a predetermined length by cutting 1/5 to 4/5 of an arc. A vasodilator according to claim 1.