JPH08317969A - Catheter with expansion unit - Google Patents

Abstract

PURPOSE: To eliminate possibility of leak or the like in a fused part by providing a catheter with an expansion unit, whose base end is fused and connected with the tip end of the outer tube, whose tip end is attached to the inner tube, and whose base end or the proximity communicates with the lumen, and thereby surely connecting the expansion unit with the outer tube. CONSTITUTION: The inner tube 1 is provided with a base end part, tip end part 12, first lumen 14 with an open end 13, and X-ray contrast marker 15 for showing the position of the expansion unit 3. The outer tube 2 is formed coaxially to the inner tube 1, equipped with a main body 21 and a tip end part 22, and arranged at a prescribed position 23, forming a second lumen 24. In addition, the tip end part 22 is composed of a noncross-linked olefin resin, the main body 21 is composed of a cross-linked olefin resin and both are fused. Further, the expansion unit 3 is fused at the base end part 32 with the tip end part 22 of the outer tube 2, with the tip end part 31 fused with the tip end 13 of the inner tube 1; the expansion unit is composed of a cross- linked olefin resin, having a bulged part communicating with the second lumen 24 in the proximity of the base end part 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catheter with an expandable body for use in a procedure for inserting and dilating a stenotic portion of a cardiac artery causing a myocardial infarction or the like.

[0002]

2. Description of the Related Art As a conventional catheter with an expander for expanding a stenosis in a blood vessel, for example, Japanese Patent Laid-Open No. 3-73167 is known.
There is one shown in Japanese Patent Publication. As shown in FIG. 6, the mounted state of the expansion body of the catheter with an expansion body described in this publication is an inner tube 101, an outer tube 102 provided coaxially with the inner tube 101, an inner tube 101 and an outer tube. The extension body 103 is attached to the outer tube 102, and the outer tube 102 and the extension body 103 are connected to each other by the tip 104 of the outer tube 102 and the extension body 10.
The fusion-bonding margins 106 and 107 of the base end portion 105 of No. 3 are overlapped and heated to perform fusion-bonding.

[0003]

In the above-mentioned catheter, the fusion bonding strength between the outer tube and the expansion body may vary greatly depending on the materials of both. Further, the expansion body and the outer tube made of an olefin resin may be cross-linked in order to increase the pressure resistance. However, when materials made of such a crosslinked olefin resin are adhered to each other by fusion bonding, high fusion strength cannot be expected, and there is a risk that leakage or the like may occur.

[0004] It is an object of the present invention to provide a catheter with an expandable body having a pressure resistant strength without fear of leakage or the like due to such low fusion strength.

[0005]

[Means for Solving the Problems] This problem is as follows (1)
This is solved by the catheter with an expandable body of the present invention shown in (3).

(1) An inner tube having a first lumen having a base end portion and a tip end portion and an opening at the tip end; and an inner tube coaxially provided with the inner tube, having a main body portion and a tip end portion, It is provided at a position retracted by a predetermined length from the tip of the inner pipe, and forms a second lumen between the inner pipe and the outer surface of the inner pipe. The tip portion is made of an uncrosslinked olefin resin and the main body portion is made of a crosslinked olefin resin. The tip portion and the body portion have an outer tube fusion-bonded to each other, and a tip portion and a base end portion, and the base end portion is fusion-bonded to the tip portion of the outer tube. Is an expansion body made of a crosslinkable olefin resin that is attached to the inner pipe and communicates with the second lumen near the base end, and the expansion body provided at the base end of the inner pipe. A first opening communicating with the first lumen and a base end of the main body of the outer tube. Catheter with expandable member having a second opening for the second lumen communicating with the.

(2) The catheter with an expandable body according to the above (1), wherein a metal reinforcement is provided inside the main body of the outer tube.

(3) The catheter with an expandable body according to the above (2), wherein the metal reinforcing body is tubular and the tip portion is coil-shaped.

The catheter with an expandable body of the present invention has the above (1).
As described above, the base end portion of the expansion body made of the crosslinked olefin resin and the tip portion of the outer pipe made of the crosslinked olefin resin are connected by fusion. These fusion splices have a higher compatibility than the cross-linked olefins and can realize strong fusion splicing. In addition, the outer tube is also made by fusion bonding the crosslinked olefin resin and the uncrosslinked olefin resin in the same manner as the adhesion between the main body portion and the tip portion. It is possible to firmly connect the outer tube of the crosslinked olefin resin and the expanded body of the crosslinked olefin resin through the indirect connection though the connection.

The term "uncrosslinked olefin-based resin" as used herein means not only an uncrosslinked olefin-based resin, but also a slightly crosslinked olefin resin, and a resin having a lower degree of crosslinking than a crosslinked olefin resin. It is a waste.

These fusion splicing can be realized as follows.

1. A metal cored bar is passed through the tip of the outer pipe of the uncrosslinked olefin resin, and a part of the main body of the crosslinked olefin resin is overlapped. This overlapped portion becomes a fusion bond.

2. Subsequently, a silicone heat-shrinkable tube is covered so as to cover the fusion-bonded portion, and heating is performed from above the silicone heat-shrinkable tube. The silicone heat-shrinkable tube is heated in a state in which the heat-shrinkable tube is heat-shrinked and the fusion-bonding margin is strongly adhered to the silicone heat-shrinking tube, so that a strong fusion-bonding strength can be obtained.

3. Next, the base end portion of the expansion body is overlapped with the tip end of the tip end portion, the overlapped portion is allowed to be fused, and a silicone heat-shrinkable tube is further covered and then heated.
As in the case of 2, the connection portion having a strong fusion strength can be obtained.

In this way, a connection with high fusion strength can be easily realized.

Next, as in the above (2), since the metal reinforcing member is provided inside the main body portion of the outer tube, the torque transmissibility is also high,
Indentation characteristics are also improved.

Further, as in the above (3), since the reinforcing body is tubular and the tip is coiled, the kink resistance is excellent. As a method of providing such a reinforcing body in the outer tube, prepare one having a diameter of the outer tube larger than the coil in advance, and insert the coil in the outer tube (however, a predetermined portion from the tip should be fused. Therefore, if the coil is not inserted) and then heated, the outer tube contracts and comes into close contact with the outer surface of the coil. When the outer tube and the reinforcing body are completely in close contact with each other, torque transmission is excellent, kink resistance is improved, and operability is excellent.

[0018]

The contents of the invention will be described in detail below with reference to the embodiments of the present invention.

[0019]

Embodiment 1 FIG. 1 is an overall view of a catheter 10 with an expandable body according to the present invention. FIG. 2 is an enlarged partial cross-sectional view of the distal end portion of the catheter 10 with the expandable body, which has the expandable body.

As shown in the figure, a catheter 10 with an expandable body includes an inner tube 1, an outer tube 2, an expandable body 3, and a hub 4 provided at a proximal end.
It consists of

The inner tube 1 has a diameter of 0.6 mm and a wall thickness of 0.075.
mm, length 1500 mm, made of high-density polyethylene, having a proximal end and a distal end 12, and having a first lumen 14 with an opening at the distal end 13, and an X-ray for indicating the position of the expansion body 3. A contrast marker (platinum coil) 15 is provided.

The outer tube 2 is provided coaxially with the inner tube 1 and has a body portion 21 and a tip portion 22. The body portion has a diameter of 1.07 mm, a length of 1270 mm, and a tip portion of a diameter of 0.9 mm. The length is 80mm and the wall thickness is 0.07
It is 5 mm. Further, it is provided at a position 23 retracted from the tip 13 of the inner pipe 1 by a predetermined length, forms a second lumen 24 with the inner surface of the outer pipe 2, and the tip portion 22 is made of an uncrosslinked olefin resin (linear low Density polyethylene (ethylene-hexene copolymer (C ₆ LLDPE)), and the main body portion 21 is a cross-linked olefin resin (linear low-density polyethylene (ethylene-hexene copolymer (C ₆ LLDPE)) electron beam cross-linked. Product), and both are fusion-spliced.

Further, the expansion body 3 has a distal end portion 31 and a proximal end portion 32, the proximal end portion 32 is fusion-bonded to the distal end portion 22 of the outer pipe 2, and the distal end portion 31 is the distal end 13 of the inner pipe 1. Cross-linked olefin resin (linear low density polyethylene (ethylene-hexene copolymer (C ₆ LLDPE (C ₆ LLDPE) having a shrinkable or foldable expansion part that communicates with the second lumen 24 in the vicinity of the proximal end 32. )) Electron beam cross-linked product)
It consists of The tip 31 has an outer diameter of 0.7 mm and a wall thickness of 0.15 mm, and the base 32 has an outer diameter of 1 mm.
The wall thickness is 0.12 mm. The expanded portion has an outer diameter of 2.5 mm when expanded and a wall thickness of 0.03 mm. The total length of the expansion body is 27 mm. The size of the expansion body can be arbitrarily changed depending on the site to which it is applied.

The hub 4 is provided at the base end of the main body portion 21 of the outer pipe 2 and the first opening 41 communicating with the first lumen 14 provided at the base end of the inner pipe 1. Second
And a second opening 42 communicating with the lumen 24.

A kink-preventing reinforcing tube 28 is provided at the connecting portion between the hub 4 and the body 21 of the outer tube 2 at the base end thereof.

3 and 4 are partial sectional views showing the fusion bonding method. FIG. 3 relates to fusion of the main body portion 21 and the tip portion 22 of the outer tube 2, and FIG. 4 relates to fusion of the tip portion 22 of the outer tube 2 and the base end portion 32 of the expansion body 3.

The fusion method will be described with reference to FIGS.

1. A metal core 5 is attached to the tip portion 22 of the outer tube 2.
0 (0.75 mm diameter, stainless steel wire (SUS30
After passing 4)), the main body portion 21 is put on the cored bar 50 so as to overlap a part of the main body portion 21. This overlapped portion becomes a fusion bond 25.

2. Subsequently, a heat shrinkable tube 26 made of silicone is covered so as to cover the portion of the fusion bond 25, and heat is applied from above the heat shrinkable tube 26 made of silicone (130 to 140 ° C.).
About 10 seconds). The silicone heat-shrinkable tube 26 is heat-sealed in a state in which the heat-shrinkable tube 26 is heat-shrinked and the fusion-bonding margin 25 is strongly adhered, so that a fusion-bonded portion having a strong fusion-bonding strength can be obtained. (See FIG. 3) 3. Next, at the tip of the tip portion 22, the base end portion 32 of the expansion body 3
Are overlapped with each other, and the overlapped portion is fused to form a margin 27, which is further covered with a heat-shrinkable tube 26 made of silicone, followed by heating. Silicone heat shrink tube 26 as in 2 above
Is heated in a state in which it is heat-shrinked and the fusion-bonding margin 27 is firmly adhered, so that a fusion-bonded portion having a strong fusion-bonding strength is obtained. (Fig. 4
In addition, in order to prevent the portion of the outer tube 2 which is not involved in the fusion of the main body portion 21 and the expansion portion of the expansion body 3 from being thermally affected during the heat fusion, a protective tube 29 is covered. It is good to put it.

4. After fusing, the silicone heat shrink tubes 26, 26 are removed.

After connecting the outer tube 2 and the expansion body 3 in this manner, the tip 13 of the inner tube 1 and the tip portion 31 of the expansion body 3 are successively connected.
Connect. The inner pipe 1 is made of high-density polyethylene resin, and the inner pipe 1 has a core metal (0.4 mm stainless wire (SUS3
04)), the tip end portion 31 of the expansion body 3 and the tip end 13 of the inner tube 1 are overlapped and covered with a heat shrinkable tube made of silicone, and then heated (at 130 to 140 ° C. for about 20 seconds).
To do. It is heat-shrinked and fused in a compressed state.

Then, after covering the reinforcing tube 28 from the base end of the main body portion 22 of the outer tube 2, the first opening portion 41 of the hub 4 is attached to the first lumen 14 and the second opening portion 42 of the hub 4.
And the second lumen 24 are connected so as to communicate with each other and fixed to the base end of the main body portion 22, and finally, the reinforcing tube 28 is slid and fixed (bonded) so as to cover the hub.

As described above, the catheter with an expandable body 1
0 is created. In the produced catheter 10 with an expandable body, the proximal end portion 32 of the expandable body 3 and the distal end portion 22 of the outer tube 2 are compatible with each other and can be reliably fused, and there is no risk of leakage or the like.

[0034]

Second Embodiment A second embodiment will be described. FIG. 5 is a partial sectional view of a catheter with an expandable body according to a second embodiment.

As shown in FIG. 5, the catheter 10 with the expandable body of the first embodiment has a structure in which a reinforcing body made of a superelastic metal pipe 50 is contained inside the outer tube 2. Reinforcement 5
0 has a diameter of 1.0 mm and a thickness of 0.07 mm, and has a coil shape from the tip to one-third of the total length, and the pitch near the tip is about 0.5 mm, and gradually tapers toward the proximal direction. The pitch is widening.

The creation method will be described.

1. A super elastic pipe 50 (total length of about 1 m 50 cm, made of titanium-nickel alloy, which is coiled from the tip to 500 mm (the coil pitch increases from the tip (coil pitch 0.5 mm) to the base end).
A diameter of 1.0 mm and a thickness of 0.07 mm) is prepared. Subsequently, a tube for forming an outer tube body (inner diameter 1.05 mm) made of a cross-linked olefin resin (electron beam cross-linked product of linear low density polyethylene (ethylene-hexene copolymer (C ₆ LLDPE))) was used as a super elastic pipe. 50 is covered with the pipe tip retracted by about 5 mm from the tip of the outer tube body.
After this, heating is performed to reduce the diameter, and the superelastic pipe 50 and the outer tube body forming tube are brought into close contact with each other. This retracted portion of the resin simple substance serves as a fusion bonding margin 25 with the tip portion 22.

The subsequent manufacturing method of the second embodiment is the same as that of the first embodiment. The second embodiment is different from the first embodiment only in the body portion 21 of the outer tube, and the other manufacturing method and configuration are the same.

The second embodiment is a reinforcing member (super elastic pipe 5
Since it contains 0), it has excellent kink resistance and shows good torque transmission. Further, since the tip portion does not include a reinforcing body, it has high flexibility, and can be formed thinner than the main body portion, so that the flexibility is high and high operability can be obtained even in a thin application site.

Further, in this embodiment, the main body portion 21 and the distal end portion 22 of the outer tube are fused first, but the proximal end portion 3 of the expansion body 3 is
2 and the tip portion 22 may be fused first.

[0041]

The catheter with an expandable body according to the present invention has an inner tube having a first lumen having a proximal end portion and a distal end portion and an opening at the distal end, and a main body portion provided coaxially with the inner tube. A second lumen is formed between the tip of the inner tube and the outer surface of the inner tube.
The tip portion is made of an uncrosslinked olefin resin, the body portion is made of a crosslinked olefin resin, and the tip portion and the body portion have an outer pipe fusion-bonded, a tip portion and a base end portion, The base end portion is fusion-bonded to the tip end portion of the outer tube, the tip end portion is attached to the inner tube, and the cross-linkable olefin resin that is in the vicinity of the base end portion and communicates with the second lumen and is contractable or foldable. An expansion body, a first opening communicating with the first lumen provided at the proximal end of the inner tube, and the second lumen provided at the proximal end of the main body of the outer tube. Since the second body has the second opening communicating with, the reliable connection between the expansion body and the outer tube is made, and there is no fear of leakage or the like at the fusion-bonded portion.

Further, the catheter with an expandable body of the present invention is excellent in kink resistance and torque transmission due to the metal reinforcement provided inside the main body of the outer tube. Further, since the tip portion is only a tube, it is thin. It can be formed, and it can be made to be particularly flexible. It is highly bent and has good operability even in a thin blood vessel. Furthermore, in the catheter with an expandable body of the present invention, since the metal reinforcing body is tubular and the distal end portion is coil-shaped, the reinforcing body has a distal end portion which is more flexible than a proximal end portion, and the entire length of the catheter is provided. The flexibility can be increased from the base end to the tip.

[Brief description of drawings]

FIG. 1 is an overall view of a catheter with an expandable body of the present invention.

FIG. 2 is an enlarged partial cross-sectional view of a distal end portion of the catheter with an expandable body of the present invention having the expandable body.

FIG. 3 is a diagram for explaining a method of fusing the body portion and the tip portion of the outer tube.

FIG. 4 is a diagram for explaining a method of fusing the distal end portion of the outer tube and the proximal end portion of the expansion body.

FIG. 5 is a partial sectional view of a catheter with an expandable body according to a second embodiment of the present invention.

FIG. 6 shows a mounting portion of a dilator of a conventional catheter with dilator.

[Explanation of symbols]

 10 ... Catheter with expander 1 ... Inner tube 12 ... Outer tube 3 ... Expander 4 ... Hub 12 ... Tip part 13 ... Tip 14 ... First Lumen 15 ... X-ray contrast marker 21 ... Main body portion 22 ... Tip portion 23 ... Retracted position 24 ... Second lumen 25, 27 ... Melt seal 26 ... Silicone Heat-shrinkable tube 28 ... Reinforcement tube 29 ... Protective tube 31 ... Tip part 32 ... Base part 41, 42 ... Opening part 50 ... Core bar 101 ... Inner tube 101 102 ... Outer tube 102 103 ... Expansion body 105 ... Proximal end portion 106, 107 ... Melt

Claims (3)

[Claims] Claim: What is claimed is: 1. An inner tube having a first lumen having a proximal end portion and a distal end portion, the distal end of which is open; and a main body portion and a distal end portion which are provided coaxially with the inner pipe. Provided at a position retracted from the tip of the pipe by a predetermined length,
A second lumen is formed between the inner tube and the outer surface, the tip portion is made of an uncrosslinked olefin resin, the body portion is made of a crosslinked olefin resin, and the tip portion and the body portion are fusion-bonded to each other. Has an outer pipe and a distal end portion and a proximal end portion, the proximal end portion being fusion-bonded to the distal end portion of the outer pipe, the distal end portion being attached to the inner pipe, and being in the vicinity of the proximal end portion. An expansion body made of a cross-linkable olefin resin that is contractible or foldable and that communicates with the second lumen; a first opening that is provided at the proximal end of the inner tube and that communicates with the first lumen; A catheter with an expandable body, comprising: a second opening provided at a base end of a body portion of the outer tube and communicating with the second lumen. 2. The catheter with an expandable body according to claim 1, wherein a metal reinforcement is provided inside the main body of the outer tube. 3. The catheter with an expandable body according to claim 2, wherein the metal reinforcing body has a tubular shape and a distal end portion has a coil shape.