JP6754271B2 - Catheter assembly - Google Patents

Description

The present invention relates to a catheter assembly that combines catheters that are inserted into a living lumen.

Treatment catheters are widely used for diagnosis or treatment in the living lumen. Treatment catheters include, for example, balloon catheters used in percutaneous coronary angioplasty (PTCA: Percutaneous Transluminal Colonary Angioplasty).

A guiding catheter is pre-inserted into the living lumen before the treatment catheter is inserted. The treatment catheter is inserted into the lumen of the guiding catheter. In recent years, in the treatment of blood vessels in the lower limbs, the procedure of inserting a guiding catheter (TRI: Trans Radial Intervention) from an arm artery, particularly a radial artery or a brachial artery, has been increasing.

Since the guiding catheter used in the TRI procedure requires a long shaft to be inserted into the radial artery having a small diameter, the outer diameter of the shaft is required to be as small as possible. On the other hand, in order to insert the treatment catheter into the lumen of the guiding catheter, the inner diameter of the shaft is required to be as large as possible. Therefore, the guiding catheter used in the TRI procedure is required to reduce the wall thickness of the shaft.

In the catheter, a reinforcing body may be provided in the shaft in order to secure sufficient strength even if the thickness of the shaft is small. The reinforcing body is generally a braided metal wire. Examples of the catheter having such a reinforcing body include those listed in Patent Document 1.

Japanese Unexamined Patent Publication No. 10-43300

The tip of the catheter is provided with a contrast-enhanced portion for visual recognition by X-ray when inserted into the living lumen. The contrast portion is formed of a resin containing a material having X-ray contrast property. A resin containing a large amount of a material having X-ray contrast property has a reduced flexibility and a reduced tensile strength. It is desirable that the tip of the catheter has high flexibility in order to improve the followability, and at the same time, it is also necessary to have X-ray contrast. Therefore, both of these are required.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a catheter assembly having a tip portion having high flexibility and X-ray contrast property.

The catheter assembly according to the present invention that achieves the above object includes an outer catheter having a long tubular outer shaft and an outer catheter.
With an inner catheter having an inner shaft that can be inserted into the lumen of the outer shaft,
The outer catheter has an outer shaft contrasting portion having X-ray contrast at the tip of the outer shaft, and has a lower X-ray contrast than the outer shaft contrast portion on the proximal end side of the outer shaft contrast portion. Has a flexible part,
The inner shaft of the inner catheter has an inner shaft contrast portion having X-ray contrast property, and has an inner shaft contrast portion.
The inner shaft contrast portion is located in a region that overlaps with the flexible portion at least in the length direction in the positional relationship when the inner shaft is inserted into the lumen of the outer shaft and inserted to a target portion of the biological lumen. Exists.

In the catheter assembly constructed as described above, the flexibility of the tip of the outer shaft can be increased by the flexible portion. Further, when the inner shaft is inserted into the lumen of the living body, the inner shaft contrast portion of the inner shaft overlaps the flexible portion in the length direction, so that the tip portion of the outer shaft can be continuously contrasted to improve visibility.

The inner shaft contrast portion also exists in a region including the tip of the inner shaft. Therefore, the position of the tip of the inner shaft, which is the tip of the catheter assembly, can be confirmed.

Further, in the inner shaft, the region of the inner shaft contrast portion is formed of a material that is more flexible than the region other than the inner shaft contrast portion. Therefore, it is possible to improve the followability to the bending of the living lumen while ensuring the rigidity of the inner shaft.

Further, the outer shaft includes a base end portion having a reinforcing body, a flexible portion located on the distal end side from the proximal end portion and not having the reinforcing body, and the outer shaft contrast portion located on the distal end side from the flexible portion. Has a tip portion and has. Therefore, at the tip of the outer shaft, stress concentration can be relaxed by changing the physical properties stepwise, and breakage of the tip can be suppressed.

Further, the outer shaft has an inner layer having a lumen along the length direction, an outer layer covering the outer peripheral side of the inner layer, and a reinforcing body arranged on the outer peripheral side of the inner layer, and the outer layer is the said. It has a tip outer layer at the tip of the outer shaft, an intermediate outer layer on the proximal side of the distal outer layer, and a proximal outer layer on the proximal side from the intermediate outer layer, and the region of the distal outer layer is the distal end. The region of the intermediate outer layer is the flexible portion, and the region of the proximal outer layer is the proximal end portion. Therefore, the flexibility of the outer shaft gradually increases from the proximal end side to the distal end side. As a result, the influence of a large difference in physical properties can be alleviated, and a tip portion having both tensile strength and flexibility can be formed.

Further, the outer shaft contrast portion and the inner shaft contrast portion are formed of a resin containing X-ray contrast-enhancing particles. Therefore, the X-ray contrast property can be easily adjusted, and the visibility of the therapeutic catheter inserted into the lumen of the outer shaft can be improved.

It is a front view of the catheter assembly of this embodiment. It is a front view of the outer catheter. It is sectional drawing of the tip part of the outer shaft. It is a partial front view of a reinforcing body. It is a front view of an internal catheter. It is the enlarged front view near the tip of the state which combined the outer catheter and the inner catheter. It is a photograph which contrasted the inner shaft, the outer shaft, and a combination thereof with X-rays, respectively. It is the enlarged front view near the tip of the state which combined the outer catheter and the inner catheter of the 2nd form.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The dimensional ratios in the drawings may be exaggerated and differ from the actual ratios for convenience of explanation. In the present specification, the side of the catheter 10 to be inserted into the living lumen is referred to as "tip" or "tip side", and the hand side to be operated is referred to as "base end" or "base end side".

The catheter assembly 1 of the present embodiment is formed by combining an outer catheter 2 having a long tubular outer shaft 3 and an inner catheter 5 having an inner shaft 6 that can be inserted into the lumen of the outer shaft 3. There is. The external catheter 2 is a guiding catheter that is inserted from a blood vessel of the arm such as the radial artery to the vicinity of a target site such as a narrowed portion of a blood vessel of the lower limb. The guiding catheter is used to guide a treatment catheter to a target site by inserting a treatment catheter such as a balloon catheter. Further, the inner catheter 5 is used to integrate with the outer shaft 3 to increase the rigidity of the catheter assembly 1 and to improve the pushability when the outer shaft 3 is inserted into the living lumen.

As shown in FIG. 1, in the catheter assembly 1, the tip of the inner catheter 5 integrated with the outer catheter 2 protrudes from the tip of the outer catheter 2. The proximal end of the inner catheter 5 is fixed to the proximal end of the outer catheter 2. As a result, the inner catheter 5 is positioned and fixed in the axial direction with respect to the outer catheter 2. When the catheter assembly 1 is inserted to a predetermined position in the living lumen, the inner catheter 5 is released from the fixation to the outer catheter 2 and is removed from the living lumen.

The external catheter 2 will be described in more detail. As shown in FIG. 2, the outer catheter 2 has an outer shaft 3 which is a long tubular body, and a hub 4 provided at a base end portion of the outer shaft 3. In addition, in FIG. 2, the region having X-ray contrast property is shown by hatching.

As shown in FIG. 3, the outer shaft 3 is a tubular body having a two-layer structure consisting of an inner layer 10 having a lumen 11 along the length direction and an outer layer 12 covering the outer peripheral side of the inner layer 10. Further, the outer shaft 3 has a reinforcing body 13 between the inner layer 10 and the outer layer 12. The outer shaft 3 is made of a flexible material. Therefore, the outer shaft 3 can be inserted along the shape of the blood vessel.

As the material of the outer layer 12, for example, thermoplastic elastomers such as styrene-based, polyolefin-based, polyurethane-based, polyester-based, polyamide-based, polybutadiene-based, transpolyisoprene-based, fluororubber-based, and chlorinated polyethylene-based can be used. As the material of the outer layer 12, one or a combination of two or more of these can be used (polymer alloy, polymer blend, laminate, etc.).

The material of the inner layer 10 is preferably a material that has low friction at a portion in contact with the medical device when a medical device such as a treatment catheter is inserted into the cavity 11. As a result, the medical device inserted in the outer shaft 3 can be moved in the length direction with a smaller sliding resistance, which contributes to the improvement of operability. Examples of such a low friction material include a fluororesin material such as polytetrafluoroethylene (PTFE).

The reinforcing body 13 is provided to reinforce the outer shaft 3. As shown in FIG. 4, the reinforcing body 13 is formed by forming a plurality of strands 30 in a mesh pattern at a constant pitch. The resin material of the outer layer 12 has entered the gap between the plurality of strands 30 of the reinforcing body 13. The material of the wire 30 is metal, and stainless steel, NiTi, or the like can be used. The cross-sectional shape of the wire 30 is a flat plate. As a result, the thickness of the reinforcing body 13 can be reduced. However, the cross-sectional shape of the wire 30 is not limited to this, and may be a circle, an ellipse, an oval, a polygon, or the like. Further, a resin material may be used as the material of the wire 30.

The outer layer 12 is further divided into three portions in the length direction of the outer shaft 3. The tip of the outer shaft 3 is the tip outer layer 20. An intermediate outer layer 21 is provided on the base end side of the tip outer layer 20. A proximal outer layer 22 is provided on the proximal side of the intermediate outer layer 21. The intermediate outer layer 21 is made of a material that is more flexible than the base end outer layer 22. Further, the tip outer layer 20 is made of a material more flexible than the intermediate outer layer 21. The hardness of the base end outer layer 22 is in the range of shore D hardness 50 to 80, more preferably in the shore D hardness 60 to 70. The hardness of the intermediate outer layer 21 is in the range of 35 to 50 shore D hardness, more preferably in the range of 45 to 50 shore D hardness. The hardness of the tip outer layer 20 is in the range of shore D hardness 30 to 50, more preferably in the shore D hardness 40 to 45.

Of the outer layers 12, the intermediate outer layer 21 and the tip outer layer 20 are thicker than the base end outer layer 22. In the regions of the intermediate outer layer 21 and the tip outer layer 20, the cross-sectional area of the outer shaft 3 is constant along the length direction.

The tip outer layer 20 contains a substance having X-ray contrast property. Specifically, particles having X-ray contrast property are mixed with the resin forming the tip outer layer 20. In this embodiment, tungsten particles are used as the X-ray contrast-enhancing particles used for the tip outer layer 20. The tungsten particles are single particles having a particle size of 0.4 to 14 μm. Tungsten particles are contained in the tip outer layer 20 in the range of 50 to 90% by weight, preferably 60 to 80% by weight. As a result, the region of the tip outer layer 20 in the outer shaft 3 becomes the outer shaft contrast portion 25 having X-ray contrast property. The particles having X-ray contrast property may be made of a material other than tungsten.

The reinforcing body 13 is provided so as to extend from the base end outer layer 22 to the intermediate outer layer 21 in the length direction of the outer shaft 3. Further, the tip of the reinforcing body 13 is located on the proximal end side of the tip of the intermediate outer layer 21. Therefore, the intermediate outer layer 21 has a base end side portion 21a having the reinforcing body 13 and a tip end side portion 21b having no reinforcing body 13.

Particles having X-ray contrast property are not mixed in the intermediate outer layer 21. Of the intermediate outer layer 21, the base end side portion 21a is provided with the reinforcing body 13 as described above. Since the reinforcing body 13 has an X-ray contrast property, the proximal end side portion 21a has an X-ray contrast property. Further, since the reinforcing body 13 is also provided on the base end outer layer 22, the base end outer layer 22 also has X-ray contrast property. On the other hand, of the intermediate outer layer 21, the distal end side portion 21b does not have the reinforcing body 13 and does not have particles having X-ray contrast property. That is, the distal end side portion 21b is more flexible than the proximal end side portion 21a and does not have X-ray contrast property. The region of the tip side portion 21b is hereinafter referred to as a flexible portion 26. As shown in FIG. 2, in the outer shaft 3, the region of the flexible portion 26 does not have X-ray contrast, and the tip side of the flexible portion 26 is the outer shaft contrast portion 25, which has X-ray contrast. The base end side of the flexible portion 26 has an X-ray contrast property because it has a reinforcing body 13.

The outer shaft 3 is required to have a high tensile strength in order to improve the pushability when inserted into the living lumen and to increase the strength when the outer shaft 3 is pulled. At the same time, flexibility is also required when the tip abuts against the inner wall surface of the living lumen. As described above, the intermediate outer layer 21 is more flexible than the proximal outer layer 22. Further, of the intermediate outer layer 21, the base end side portion 21a has the reinforcing body 13 and the flexible portion 26 does not have the reinforcing body 13, so that the flexible portion 26 is more flexible than the proximal end side portion 21a. .. Further, the tip outer layer 20 is more flexible than the intermediate outer layer 21. That is, the flexibility of the outer shaft 3 gradually increases from the proximal end side to the distal end side. As a result, the influence of a large difference in physical properties can be alleviated, and a tip portion having both tensile strength and flexibility can be formed. Further, since the flexible portion 26 does not have particles having X-ray contrast property, it has high tensile strength as well as flexibility.

Further, the outer shaft 3 has an inner layer 10 that is continuous over the base end outer layer 22, the intermediate outer layer 21, and the tip outer layer 20. This means that when a medical device such as a balloon catheter is removed, the sliding resistance of the tip of the outer shaft 3 with respect to the medical device is reduced, and the medical device is caught by the tip of the outer shaft 3 and the tip of the outer shaft 3 is caught. It is possible to prevent the portion from being caught in the inner cavity 11 of the outer shaft 3.

Next, the internal catheter 5 will be described. As shown in FIG. 5, the inner catheter 5 has an inner shaft 6 which is a long tubular body, and a proximal end fixing portion 7 provided at a proximal end portion of the inner shaft 6. The inner shaft 6 has a lumen through which a guide wire (not shown) can be inserted in the length direction. Also in FIG. 5, the portion having the X-ray contrast property is shown by hatching.

The proximal end fixing portion 7 is capable of inserting the proximal end portion of the hub 4 of the outer catheter 2, and has a spiral groove portion 7a on the inner peripheral surface thereof. By inserting the proximal end portion of the hub 4 into the proximal end fixing portion 7 and engaging it with the groove portion 7a, the inner catheter 5 is integrated with the outer catheter 2 and the inner catheter 5 becomes the outer catheter as shown in FIG. Positioning and fixing in the axial direction with respect to 2.

The inner shaft 6 has a proximal shaft portion 40 on the proximal end side and an inner shaft contrasting portion 41 having X-ray contrast enhancement on the distal end side. The inner shaft 6 can be made of the same material as the outer shaft 3. The inner shaft contrast portion 41 is made of a material that is more flexible than the proximal shaft portion 40. Further, particles having X-ray contrast property are mixed in the inner shaft contrast unit 41. The particles having X-ray contrast property in the inner shaft contrast unit 41 are tungsten particles like the tip outer layer 20 of the outer shaft 3. The tungsten particles are a mixture of primary particles and secondary particles, and have a particle size in the range of 0.4 to 19 μm, preferably 0.8 to 19 μm. Further, the tungsten particles are contained in the inner shaft contrast portion 41 at a ratio of 10 to 30% by weight. The particles having X-ray contrast property may be made of a material other than tungsten. Further, the inner shaft contrast unit 41 may be a metal marker.

The X-ray contrast property in the state where the outer catheter 2 and the inner catheter 5 are combined will be described. As described above, in the state where the inner catheter 5 is fixed to the outer catheter 2, the inner shaft 6 is in a state of protruding from the tip of the outer shaft 3 toward the tip side. In FIG. 6, the region of the inner shaft 6 having X-ray contrast and the region of the outer shaft 3 having X-ray contrast are shown by different hatching. As shown in FIG. 6, in the inner shaft contrasting portion 41, the tip position 41a is located at the tip position of the inner shaft 6, and the proximal end position 41b is located at the proximal end side of the flexible portion 26 of the outer shaft 3. As described above, in the outer shaft 3, the region having the outer shaft contrast portion 25 at the tip portion and the reinforcing body 13 on the proximal end side of the flexible portion 26 has X-ray contrast, and the flexible portion 26 has X-ray contrast. It does not have contrast. By combining the outer catheter 2 and the inner catheter 5, the inner shaft contrast portion 41 of the inner catheter 5 is arranged in the region of the flexible portion 26, and the region having X-ray contrast property is continuous from the proximal end side to the distal end portion.

FIG. 7A is a photograph of the inner shaft contrasting portion 41 of the inner shaft 6 contrasted with X-rays. The entire area of the inner shaft contrast unit 41 is imaged along the length direction. FIG. 7B is an X-ray image of the vicinity of the tip of the outer shaft 3. In the outer shaft 3, the region of the outer shaft contrast portion 25 is imaged in the vicinity of the tip thereof, but the region of the flexible portion 26 is not contrasted, and the region on the proximal end side of the flexible portion 26 has the reinforcing body 13. Is contrasted with. Therefore, the outer shaft 3 is imaged so that the tip end portion floats from the proximal end side.

FIG. 7 (c) is a photograph of an inner shaft 6 inserted into the lumen of the outer shaft 3 to a predetermined position and imaged by X-ray. When the inner shaft 6 is inserted through the outer shaft 3, the contrast-enhancing inner shaft contrast-enhancing portion 41 is imaged over the tip portion of the outer shaft 3 and the tip side thereof. Since the inner shaft contrast portion 41 is arranged in the region of the flexible portion 26 of the outer shaft 3 in the length direction, the tip portion of the outer shaft 3 including the region of the flexible portion 26 having no X-ray contrast property is X-ray. Is continuously imaged by. Therefore, the image of the outer shaft 3 is continuous from the base end side to the tip end side, and the tip end portion of the outer shaft 3 is easily visible. In particular, in a blood vessel that bends three-dimensionally, if the tip portion of the outer shaft 3 is separated and imaged on the proximal end side and the distal end side, it is difficult to grasp the tip position of the outer shaft 3. On the other hand, in the catheter assembly 1 of the present embodiment, since the region of the flexible portion 26 is continuously imaged by the inner shaft contrast portion 41, the tip position of the outer shaft 3 can be easily recognized, and the outer shaft 3 can be easily recognized. Accurate positioning can be performed.

The catheter assembly 1 of the present embodiment is provided with a flexible portion 26 having no X-ray contrast property in order to increase the flexibility of the tip portion of the outer shaft 3. Further, when the outer shaft 3 is inserted into the biological lumen, the inner shaft 6 is inserted into the lumen of the outer shaft 3, and the inner shaft contrast portion 41 of the inner shaft 6 is arranged in the region of the flexible portion 26. There is. Therefore, while ensuring the flexibility of the tip portion of the outer shaft 3, continuous contrast enhancement of the tip portion of the outer shaft 3 can be ensured at the time of insertion into the living lumen, and these can be compatible with each other.

Further, in the catheter assembly 1, since the region of the tip outer layer 20 having X-ray contrast property and the inner shaft contrast portion 41 overlap each other in the length direction, the tip of the outer shaft 3 is subjected to X-ray contrast. The portion is imaged darker than before the insertion of the inner shaft 6. Therefore, sufficient visibility can be obtained even if the proportion of X-ray contrast-enhancing particles contained in the tip outer layer 20 of the outer shaft 3 is small, and a decrease in tensile strength at the tip of the outer shaft 3 can be suppressed. ..

Further, since the tip position of the outer shaft 3 can be clearly recognized, the tip position of the outer shaft 3 can be accurately positioned at a predetermined position when the catheter assembly 1 is inserted into the living lumen. Further, after the inner shaft 6 is removed, only the outer shaft contrast portion 25 remains, and the contrast property of the tip portion of the outer shaft 3 is lowered. This makes it possible to improve the visibility of the marker of the therapeutic catheter that is inserted into the outer shaft 3 at the tip of the outer shaft 3.

When the outer catheter 2 through which the inner catheter 5 is inserted is inserted to a predetermined position in the living lumen, the inner catheter 5 is removed and the image imaged by X-ray is in the state shown in FIG. 7 (b). However, since the outer catheter 2 does not move after the inner catheter 5 is removed, there is no particular problem even if the tip of the outer shaft 3 is imaged so as to float from the proximal end side.

The region of the inner catheter 5 where the inner shaft contrast portion 41 is provided may have a different form. As shown in FIG. 8, the inner shaft 6 of the second form has a tip side inner shaft contrast portion 42 provided at the tip portion and a proximal end side inner shaft contrast portion 43 provided at the proximal end side. There is. The distal inner shaft contrast portion 42 and the proximal inner shaft contrast portion 43 are not continuous and are formed in distant regions.

The tip side inner shaft contrast unit 42 is provided to indicate the tip position of the inner shaft 6. The base end side inner shaft contrast portion 43 is formed in a region that overlaps the region of the flexible portion 26 of the outer shaft 3 in the length direction in a state where the inner shaft 6 is inserted into the outer shaft 3 to a predetermined position. As described above, if the proximal side inner shaft contrast portion 43 is formed at least in the region overlapping the region of the flexible portion 26 of the outer shaft 3 in the length direction, the X-ray contrast property is exhibited in the state of the catheter assembly 1. The region of the flexible portion 26 that does not have the above can be continuously imaged, and the visibility of the tip portion of the outer shaft 3 can be improved. Further, since the tip side inner shaft contrast portion 42 is provided at the tip of the inner shaft 6, the tip position of the inner shaft 6 can be imaged, and the tip position can be visually recognized in the state of the catheter assembly 1. It can be inserted into the living lumen while being inserted.

As described above, the catheter assembly 1 according to the present embodiment includes an outer catheter 2 having a long tubular outer shaft 3, an inner catheter 5 having an inner shaft 6 that can be inserted into the lumen of the outer shaft 3, and an inner catheter 5. The outer catheter 2 has an outer shaft contrasting portion 25 having X-ray contrast at the tip of the outer shaft 3, and X from the outer shaft contrasting portion 25 on the proximal end side of the outer shaft contrasting portion 25. The inner shaft 6 of the inner catheter 5 has an inner shaft contrasting portion 41 having an X-ray contrast property, and the inner shaft contrasting portion 41 has an inner shaft 6 as an outer shaft 3 having a flexible portion 26 having low line contrast. It exists in a region overlapping the flexible portion 26 at least in the length direction in a state of being inserted into the lumen of the. According to this catheter assembly 1, the flexibility of the tip of the outer shaft 3 can be increased by the flexible portion 26. Further, when the inner shaft 6 is inserted into the living lumen, the inner shaft contrast portion 41 of the inner shaft 6 overlaps the flexible portion 26 in the length direction, so that the tip portion of the outer shaft 3 can be continuously imaged to improve visibility.

The inner shaft contrast unit 41 also exists in a region including the tip of the inner shaft 6. Therefore, the position of the tip of the inner shaft 6 which is the tip of the catheter assembly 1 can be confirmed.

Further, in the inner shaft 6, the region of the inner shaft contrast portion 41 is formed of a material that is more flexible than the region other than the region other than the inner shaft contrast portion 41. Therefore, while ensuring the rigidity of the inner shaft 6, it is possible to improve the followability to bending of the living lumen and the like.

Further, the outer shaft 3 has a base end portion having a reinforcing body 13, a flexible portion 26 located on the distal end side of the proximal end portion and having no reinforcing body 13, and an outer shaft contrast portion located on the distal end side of the flexible portion 26. It has a tip having 25. Therefore, at the tip of the outer shaft 3, stress concentration can be relaxed by changing the physical properties stepwise, and breakage of the tip can be suppressed.

Further, the outer shaft 3 has an inner layer 10 having a cavity along the length direction, an outer layer 12 covering the outer peripheral side of the inner layer 10, and a reinforcing body 13 arranged on the outer peripheral side of the inner layer 10, and the outer layer 12 Has a tip outer layer 20 at the tip of the outer shaft 3, an intermediate outer layer 21 on the proximal side of the distal outer layer 20, and a proximal outer layer 22 on the proximal side of the intermediate outer layer 21, and the region of the distal outer layer 20 is The tip portion, the region of the intermediate outer layer 21 is the flexible portion 26, and the region of the proximal outer layer 22 is the proximal end portion. Therefore, the flexibility of the outer shaft 3 gradually increases from the proximal end side to the distal end side. As a result, the influence of a large difference in physical properties can be alleviated, and a tip portion having both tensile strength and flexibility can be formed.

Further, the outer shaft contrast unit 25 and the inner shaft contrast unit 41 are formed of a resin containing X-ray contrast-enhancing particles. Therefore, the X-ray contrast property can be easily adjusted, and the visibility of the therapeutic catheter inserted into the lumen of the outer shaft 3 can be improved.

The present invention is not limited to the above-described embodiment, and various modifications can be made by those skilled in the art within the technical idea of the present invention.

1 Catheter assembly 2 Outer catheter 3 Outer shaft 4 Hub 5 Inner catheter 6 Inner shaft 7 Base end fixing part 10 Inner layer 11 Inner cavity 12 Outer layer 13 Reinforcement body 20 Tip outer layer 21 Intermediate outer layer 22 Base end outer layer 25 Outer shaft contrast part 26 Flexible Part 30 Wire 40 Base shaft part 41 Inner shaft contrast part

Claims (6)

An outer catheter with a long tubular outer shaft,
With an inner catheter having an inner shaft that can be inserted into the lumen of the outer shaft,
The outer catheter has an outer shaft contrasting portion having X-ray contrast at the tip of the outer shaft, and has a lower X-ray contrast than the outer shaft contrast portion on the proximal end side of the outer shaft contrast portion. Has a flexible part,
The inner shaft of the inner catheter has an inner shaft contrast portion having X-ray contrast property, and has an inner shaft contrast portion.
The inner shaft contrast portion is located in a region that overlaps with the flexible portion at least in the length direction in the positional relationship when the inner shaft is inserted into the lumen of the outer shaft and inserted to the target portion of the biological lumen. The existing catheter assembly. The catheter assembly according to claim 1, wherein the inner shaft contrast unit also exists in a region including the tip of the inner shaft. The catheter assembly according to claim 1 or 2, wherein the inner shaft has a region of the inner shaft contrast portion formed of a material that is more flexible than a region other than the inner shaft contrast portion. The outer shaft has a base end portion having a reinforcing body, a flexible portion located on the distal end side from the proximal end portion and not having the reinforcing body, and the outer shaft contrast portion located on the distal end side from the flexible portion. The catheter assembly according to any one of claims 1 to 3, which has a tip portion. The outer shaft has an inner layer having a lumen along the length direction, an outer layer covering the outer peripheral side of the inner layer, and a reinforcing body arranged on the outer peripheral side of the inner layer.
The outer layer has a tip outer layer at the tip of the outer shaft, an intermediate outer layer on the proximal side of the distal outer layer, and a proximal outer layer on the proximal side of the intermediate outer layer.
The catheter assembly according to claim 4, wherein the region of the tip outer layer is the tip portion, the region of the intermediate outer layer is the flexible portion, and the region of the proximal outer layer is the proximal end portion. The catheter assembly according to any one of claims 1 to 5, wherein the outer shaft contrast portion and the inner shaft contrast portion are formed of a resin containing X-ray contrast particles.