JP2017113329A - catheter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catheter having better operability.SOLUTION: A catheter 100 includes: a sheath body (tubular body 10); a lumen (sub-lumen 42) formed inside the sheath body in a pierced manner; and an operation wire 60 piercing into the lumen and connected to the distal end part of the sheath body. The distal end part of the catheter is bent by the operation wire 60 pulled. Slide resistance between the peripheral wall of the lumen ad the operation wire 60 is larger at the distal end part than slide resistance at an intermediate part between the distal end part of the sheath body and the proximal end part thereof.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a catheter.

  In recent years, catheters that can be introduced into a body cavity and used by manipulating the direction of entry into the body cavity by bending the distal end portion have been provided.

  For example, Patent Document 1 describes a catheter in which two sub-lumens (wire lumens of the same document) having a smaller diameter are provided around a main lumen (central lumen of the document). . An operation line (a turning wire in the same document) is inserted into the sub-lumen, and the distal end of the catheter is bent by operating the operation handle on the proximal end side and pulling the operation line. .

JP 2006-192269 A

  However, in the catheter as described in Patent Document 1, the distal end portion is bent with an excessively large curvature, so that good operability is obtained when the catheter is advanced from a thick blood vessel into a thin blood vessel. It may not be possible.

  The present invention has been made in view of the above problems, and provides a catheter with better operability.

The present invention includes a sheath body, a lumen formed in the sheath body, and an operation line that is inserted through the lumen and connected to a distal end portion of the sheath body, A catheter in which the distal end bends when an operation line is pulled;
The sliding resistance between the peripheral wall of the lumen and the operation line is greater at the distal end than at the intermediate portion between the distal end and the proximal end of the sheath body. A catheter is provided.

  According to the present invention, the operability of the catheter can be improved.

It is a longitudinal cross-sectional view of the catheter which concerns on 1st Embodiment. It is a transverse cross section of the catheter concerning a 1st embodiment. 1 is an enlarged longitudinal sectional view of a catheter according to a first embodiment. It is a schematic diagram for demonstrating the behavior of the catheter which concerns on embodiment. It is a schematic diagram for demonstrating the behavior of the catheter which concerns on a comparison form. It is a longitudinal cross-sectional view of the catheter which concerns on 2nd Embodiment. It is a longitudinal cross-sectional view of the catheter which concerns on 3rd Embodiment. It is a longitudinal cross-sectional view of the catheter which concerns on 4th Embodiment. It is a longitudinal cross-sectional view of the catheter which concerns on 5th Embodiment. It is explanatory drawing of the measuring method of the sliding resistance of the surrounding wall of an auxiliary lumen (lumen), and an operation line.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that in all the drawings, the same components are denoted by the same reference numerals, and redundant description will be omitted as appropriate.

[First Embodiment]
1-3 is a figure which shows the catheter 100 which concerns on 1st Embodiment, Among these, FIG. 1 is sectional drawing (longitudinal sectional view) which cut the catheter 100 along the longitudinal direction, FIG. 2 is a catheter. FIG. 3 is a cross-sectional view (transverse cross-sectional view) obtained by cutting 100 perpendicularly to the longitudinal direction, and FIG. 3 is a schematic and enlarged vertical cross-sectional view of FIG. 1 is a cross-sectional view taken along a line II in FIG. 2, and FIG. 2 is a cross-sectional view taken along a line II-II in FIG. In FIG. 3, the left side is the distal side (tip side), and the right side is the proximal side (base end side). In FIG. 3, in the configuration shown in FIG. 1, one subtube 40, an operation line 60 inserted into the subtube 40, and a sub-lumen 42 that is an internal space of the subtube 40. The outer layer 50 around the subtube 40 is selectively shown, and the other configurations are not shown.

The catheter 100 of the present embodiment includes a sheath body (tubular body 10), a lumen (in the case of the present embodiment, a secondary lumen 42) formed in the sheath body, a lumen and a sheath. And a manipulation line 60 connected to the distal end portion of the main body, and the distal end portion is bent when the manipulation line 60 is pulled.
The sliding resistance between the peripheral wall of the lumen and the operation line 60 is higher at the distal end than at the intermediate portion between the distal end and the proximal end of the sheath body.
Thereby, since it can suppress that the front-end | tip part of a sheath main body will be bent with an excessively large curvature (too small curvature radius), while being able to adjust the direction of the front-end | tip of the tubular main body 10 easily, It becomes easy to allow the tip to enter a desired body cavity.
Here, the sliding resistance between the peripheral wall of the lumen and the operation line 60 is the resistance when the operation line 60 is moved in the axial direction relative to the lumen of the unit length with the sheath body bent. Means the size of

As shown in FIGS. 1 and 3, in the case of the present embodiment, the inner diameter of the secondary lumen 42 at the distal end portion of the tubular body 10 () is smaller than the inner diameter of the secondary lumen 42 at the intermediate portion of the tubular body 10. As a result, the sliding resistance between the peripheral wall of the sub-lumen 42 and the operation line 60 is larger at the distal end than at the intermediate portion.
More specifically, the inner diameter of the secondary lumen 42 is constant from the intermediate portion to the proximal end portion of the tubular body 10 and is locally reduced at the distal end portion.

In the case of the present embodiment, the sub-lumen 42 is configured by the internal space of the sub-tube 40 embedded in the tubular main body 10. And the internal diameter of the subtube 40 in the front-end | tip part of the tubular main body 10 is smaller than the internal diameter of the subtube 40 in the intermediate part of the tubular main body 10. FIG. Such a configuration can be realized, for example, by selectively heating and pressurizing the distal end portion of the tubular main body 10 using a heat shrinkable tube or the like, and crushing the sub tube 40 at the distal end portion.
That is, the catheter 100 includes a tube (subtube 40) embedded in the tubular body 10, the inner space of the tube forms a lumen, and the tube is crushed at the distal end portion of the tubular body 10.
By adopting such a configuration, in the catheter 100 of the type having the sub-lumen 42 constituted by the sub-tube 40, the inner diameter of the sub-lumen 42 at the distal end is larger than the inner diameter of the sub-lumen 42 at the intermediate portion. A small configuration can be realized.

  Hereinafter, this embodiment will be described in more detail. The catheter 100 of this embodiment is an intravascular catheter that is used by inserting the tubular body 10 into a blood vessel.

  The tubular main body 10 is a hollow tubular and long member in which a main lumen (main lumen) 20 is formed. More specifically, the tubular body 10 is formed with an outer diameter and a length that allow entry into any of the eight sub-regions of the liver.

  The tubular body 10 has a laminated structure. As shown in FIG. 2, the tubular main body 10 is configured by laminating an inner layer 24, a first outer layer 52, and a second outer layer 54 in order from the inner diameter side around the main lumen 20. A hydrophilic layer (not shown) is formed on the outer surface of the second outer layer 54. The inner layer 24, the first outer layer 52, and the second outer layer 54 are made of a flexible resin material, and each has an annular shape and a substantially uniform thickness. The first outer layer 52 and the second outer layer 54 may be collectively referred to as the outer layer 50.

  The inner layer 24 is the innermost layer of the tubular body 10, and the main lumen 20 is defined by the inner wall surface thereof. The cross-sectional shape of the main lumen 20 is not particularly limited, but is circular in this embodiment. In the case of the main lumen 20 having a circular cross section, the diameter may be uniform over the longitudinal direction of the tubular body 10 or may vary depending on the position in the longitudinal direction. For example, in a part or all of the length region of the tubular main body 10, the diameter of the main lumen 20 can be tapered so as to continuously expand from the distal end to the proximal end.

  Examples of the material of the inner layer 24 include a fluorine-based thermoplastic polymer material. Specific examples of the fluorine-based thermoplastic polymer material include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and perfluoroalkoxy fluororesin (PFA). By configuring the inner layer 24 with such a fluorine-based polymer material, the delivery property when supplying a drug solution or the like through the main lumen 20 is improved. Further, when the guide wire is inserted into the main lumen 20, the sliding resistance of the guide wire is reduced.

  The outer layer 50 occupies most of the thickness of the tubular body 10. The outer layer 50 of the present embodiment includes a first outer layer 52 having an annular cross section that encloses the holding wire 70, and a second outer layer having an annular cross section that is provided around the first outer layer 52 and encloses the second reinforcing layer 80. 54.

  Inside the first outer layer 52 corresponding to the inner layer of the outer layer 50, a wire reinforcing layer 30, a sub tube (tube) 40, and a holding wire 70 are provided in order from the inner diameter side. A second reinforcing layer 80 is provided inside the second outer layer 54 corresponding to the outer layer of the outer layer 50. The second reinforcing layer 80 is in contact with the outer surface of the first outer layer 52. The wire reinforcing layer 30 and the second reinforcing layer 80 are arranged coaxially with the tubular main body 10. The 2nd reinforcement layer 80 is spaced apart and arrange | positioned so that the circumference | surroundings of the wire reinforcement layer 30 and the subtube 40 may be surrounded.

As the material of the outer layer 50, a thermoplastic polymer material can be used. As this thermoplastic polymer material, polyimide (PI), polyamideimide (PAI), polyethylene terephthalate (PET), polyethylene (PE), polyamide (PA), polyamide elastomer (PAE), polyether block amide (PEBA), etc. Mention may be made of nylon elastomers, polyurethane (PU), ethylene-vinyl acetate resin (EVA), polyvinyl chloride (PVC) or polypropylene (PP).
The outer layer 50 may be mixed with an inorganic filler. Examples of the inorganic filler include contrast agents such as barium sulfate and bismuth subcarbonate. By mixing a contrast agent in the outer layer 50, the X-ray contrast property of the tubular body 10 in the body cavity can be improved.

  The first outer layer 52 and the second outer layer 54 are made of the same or different resin material. Although the boundary surface between the first outer layer 52 and the second outer layer 54 is clearly shown in FIG. 2, the present invention is not limited to this. When the 1st outer layer 52 and the 2nd outer layer 54 are comprised with the same kind of resin material, both layers are united naturally and do not need to have a clear interface. That is, the outer layer 50 of the present embodiment may be formed of a multilayer in which the first outer layer 52 and the second outer layer 54 can be distinguished from each other, or the first outer layer 52 and the second outer layer 54 are integrated. It may be configured as a single layer.

The wire reinforcing layer 30 is a protective layer that is provided on the inner diameter side of the operation line 60 in the tubular body 10 and protects the inner layer 24. The presence of the wire reinforcing layer 30 on the inner diameter side of the operation line 60 prevents the operation line 60 from being exposed to the main lumen 20 by breaking the first outer layer 52 and the inner layer 24.
The wire reinforcing layer 30 is formed by winding a reinforcing wire 32. The material of the reinforcing wire 32 includes a metal material such as tungsten (W), stainless steel (SUS), nickel titanium alloy, steel, titanium, copper, titanium alloy or copper alloy, as well as the inner layer 24 and the first outer layer 52. Also, a resin material such as polyimide (PI), polyamideimide (PAI) or polyethylene terephthalate (PET) having high shear strength can be used. In this embodiment, the reinforcing wire 32 is a fine stainless steel wire.

  The wire reinforcing layer 30 is configured by winding the reinforcing wire 32 in a coil or braiding it in a mesh shape. The number of the reinforcing wires 32, the coil pitch, and the number of meshes are not particularly limited. Here, the number of meshes of the wire reinforcing layer 30 refers to the number of intersections (number of eyes) per unit length (1 inch) viewed in the extending direction of the reinforcing wires 32.

  The reinforcing wire 32 is wound obliquely around the inner layer 24. An angle formed by the extending direction of the reinforcing wire 32 with respect to the radial direction of the inner layer 24 is referred to as a pitch angle of the reinforcing wire 32. When the reinforcing wires 32 are wound at a dense pitch, the pitch angle becomes a small angle. Conversely, when the reinforcing wire 32 is wound at a shallow angle along the axial center of the tubular body 10, the pitch angle is a large angle close to 90 degrees. The pitch angle of the reinforcing wire 32 of the present embodiment is not particularly limited, but can be 30 degrees or more, preferably 45 degrees or more and 75 degrees or less.

  As the wire reinforcing layer 30 of this embodiment, a blade layer in which a reinforcing wire 32 is braided is illustrated. The first outer layer 52 is impregnated between the wire reinforcing layer 30 and the subtube 40.

The second reinforcing layer 80 is a protective layer that is provided on the outer diameter side of the operation line 60 in the tubular body 10 and protects the second outer layer 54. The presence of the second reinforcing layer 80 on the outer diameter side of the operation line 60 prevents the operation line 60 from being exposed to the outside of the tubular body 10 by breaking the second outer layer 54 and the hydrophilic layer (not shown). To do.
The second reinforcing layer 80 is formed by winding the second reinforcing wire 82 in a coiled or mesh shape. For the second reinforcing wire 82, the above-described materials exemplified as the reinforcing wire 32 of the wire reinforcing layer 30 can be used. The second reinforcing wire 82 and the reinforcing wire 32 may be made of the same material or different materials. In the present embodiment, the second reinforcing wire 82 is exemplified by a blade layer formed by braiding fine wires made of the same type of material (stainless steel) as the reinforcing wire 32 into a mesh shape.

The wire diameters of the second reinforcing wire 82 and the reinforcing wire 32 may be the same or different. In the present embodiment, the second reinforcing wire 82 and the reinforcing wire 32 have the same wire diameter.
Further, the size of the number of the reinforcing wires 32 constituting the wire reinforcing layer 30 and the number of the second reinforcing wires 82 constituting the second reinforcing layer 80 are not particularly limited, but are the same in this embodiment. FIG. 2 shows a blade layer composed of 16 wires (reinforcing wire 32, second reinforcing wire 82) in both the wire reinforcing layer 30 and the second reinforcing layer 80.

The sub-tube 40 is a hollow tubular member that defines a sub-lumen 42. The subtube 40 is embedded in the outer layer 50 (first outer layer 52). The subtube 40 can be made of, for example, a thermoplastic polymer material. Examples of the thermoplastic polymer material include low friction resin materials such as polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), or tetrafluoroethylene / hexafluoropropylene copolymer (FEP).
The subtube 40 is made of a material having a higher bending rigidity and tensile elastic modulus than the outer layer 50.

  The outer surface of the sub-tube 40 is subjected to etching treatment such as metal sodium treatment or plasma treatment. Thereby, the adhesiveness of the subtube 40 and the outer layer 50 is improved.

  As shown in FIG. 2, two subtubes 40 are arranged around the wire reinforcing layer 30 so as to face each other by 180 degrees, and operation lines 60 are inserted into the two subtubes 40, respectively. The two sub tubes 40 are parallel to the axial direction of the tubular body 10.

  The two sub tubes 40 are arranged on the same circumference so as to surround the main lumen 20. Instead of this embodiment, three or four subtubes 40 may be arranged around the main lumen 20 at equal intervals. In this case, the operation lines 60 may be arranged on all the sub tubes 40 or the operation lines 60 may be arranged on some of the sub tubes 40.

  The operation line 60 is loosely inserted in the sub tube 40 so as to be slidable. The distal end portion of the operation line 60 is fixed to the distal portion DE of the tubular main body 10. By pulling the operation line 60 to the proximal end side, a tensile force is applied to a position that is eccentric with respect to the axial center of the tubular body 10, so that the tubular body 10 bends. Since the operation line 60 of the present embodiment is extremely thin and highly flexible, even if the operation line 60 is pushed distally, a pushing force is not substantially applied to the distal portion DE of the tubular body 10.

  The operation wire 60 may be formed of a single wire, but may be a stranded wire formed by twisting a plurality of thin wires. The number of fine wires constituting one stranded wire of the operation wire 60 is not particularly limited, but is preferably 3 or more. A preferable example of the number of thin wires is seven or three.

  Here, the operation wire 60 is, for example, a stranded wire in which a plurality of (seven in this embodiment) strands are twisted together. More specifically, for example, seven strands are integrated by spirally winding six strands (peripheral strands) around one strand (center strand). Twisted together. The six peripheral strands are arranged at the vertices of a hexagon centered on the central strand. The wire diameter of the operation line 60 refers to the diameter of a circumscribed circle including seven strands (a central strand and a peripheral strand).

  Alternatively, the operation line 60 may be one in which three strands are twisted together. The diameter of the operation line 60 in this case also refers to the diameter of a circumscribed circle that includes three strands. In addition, when the operation wire 60 is formed by twisting a plurality of strands having the same diameter, the number of strands is preferably 3 or 7. By setting it as these numbers, it will be in the state twisted together most closely so that strands may mutually contact | adhere in the circumferential direction and radial direction.

  As the operation wire 60 (element wire), low carbon steel (piano wire), stainless steel (SUS), corrosion-resistant coated steel wire, titanium or titanium alloy, or metal wire such as tungsten can be used. In addition, as the operation line 60 (elementary wire), polyvinylidene fluoride (PVDF), high density polyethylene (HDPE), poly (paraphenylenebenzobisoxazole) (PBO), polyether ether ketone (PEEK), polyphenylene sulfide Polymer fibers such as (PPS), polybutylene terephthalate (PBT), polyimide (PI), polytetrafluoroethylene (PTFE), or boron fiber can be used.

  The holding wire 70 winds the subtube 40 and the wire reinforcing layer 30 together. The holding wire 70 is formed by winding the coil around the subtube 40 or braiding it in a mesh shape. Among these, the holding wire 70 is a coil, and more specifically, a coil in which a plurality of strands are wound in multiple strips (multi-strand coils).

  The holding wire 70 is wound in a spiral shape so as to surround the outside of the pair of subtubes 40 arranged to face each other around the main lumen 20. The winding shape of the holding wire 70 of the present embodiment is a substantially elliptical shape or a substantially rhombic shape in which the arrangement direction of the subtubes 40 is the major axis direction. In FIG. 2, the holding wire 70 whose winding shape forms a substantially rhombus is shown by a broken line. The holding wire 70 is in contact with the peripheral surface of the sub-tube 40, specifically, the outer surface that is opposite to the axis of the main lumen 20. Here, the approximate rhombus means that the first diagonal line is longer than the second diagonal line, and the first diagonal line and the second diagonal line are substantially orthogonal. The approximate rhombus mentioned here includes a rhombus, a flat polygon such as a kite shape, a flat hexagon, and a flat octagon. The substantially elliptical shape includes an elliptical shape such as an oval shape as well as an elliptical shape or an oval shape.

  In the present embodiment, the main lumen 20 is circular and disposed at the center of the tubular body 10, and the two sub tubes 40 are illustrated as being 180 degrees opposite each other around the main lumen 20. (N) sub-tubes 40 may be uniformly distributed around the main lumen 20. In this case, the winding shape of the holding wire 70 may be a rounded N-square shape with each subtube 40 as a corner.

  The holding wire 70 is in contact with the outer surface of the wire reinforcing layer 30 on both sides or one side in the minor axis direction orthogonal to the major axis direction. In the present embodiment, as shown in FIG. 2, 16 reinforcing wires 32 are braided by spirally winding 8 pieces in opposite directions, and there are 8 intersections between the reinforcing wires 32 in the circumferential direction of the inner layer 24. Is formed. The holding wire 70 of the present embodiment is in contact with the reinforcing wire 32 so as to run over the intersections of the reinforcing wires 32 at positions corresponding to both sides in the minor axis direction of the substantially rhombic wound shape.

  The inner surface of the subtube 40 is in contact with the outer surface of the wire reinforcing layer 30 (see FIG. 1). That is, the holding wire 70 is spirally wound in contact with the outer surface of the pair of subtubes 40 and the wire reinforcing layer 30 corresponding to a hard point. In particular, the holding wire 70 of this embodiment is in contact with the outer surface of the wire reinforcing layer 30 on both sides in the minor axis direction. As a result, the holding wire 70 is wound together with the subtube 40 and the wire reinforcing layer 30 in close contact with each other without loosening. For this reason, even if it passes through the formation process of the outer layer 50, the subtube 40 can maintain a parallel state with respect to the wire reinforcement layer 30 with high precision. That is, the holding wire 70 has an elliptical shape, and the holding wire 70 is wound with tension applied to the wire reinforcing layer 30 and the subtube 40 so as to hold the subtube 40 at both ends of the long diameter. Thereby, the position shift of the subtube 40 to the circumferential direction of the wire reinforcement layer 30 is prevented.

  When viewed in the longitudinal direction of the tubular body 10, the holding wire 70 is wound over substantially the entire length of the subtube 40. Accordingly, the relative position between the wire reinforcing layer 30 and the subtube 40 is fixed by the holding wire 70 in a state where the pair of subtubes 40 is maintained parallel to the axial direction of the tubular main body 10 along the surface of the wire reinforcing layer 30. Has been.

As the material of the holding wire 70, any of the metal materials and resin materials described above that can be used as the reinforcing wire 32 can be used. In the present embodiment, the holding wire 70 is made of a material different from that of the reinforcing wire 32. The ductility of the holding wire 70 is preferably higher than the ductility of the reinforcing wire 32. Specifically, austenitic soft stainless steel (W1 or W2), which is a dull material, or copper or copper alloy is used for the holding wire 70, while tungsten or stainless spring steel can be used for the reinforcing wire 32. .
By using a highly ductile material for the holding wire 70, the holding wire 70 is loosened when the holding wire 70 is coiled or braided into a mesh shape (coil winding in this embodiment) around the sub-tube 40. The sub-tube 40 is fixed by being stretched and deformed plastically. On the other hand, since the wire reinforcing layer 30 is a member that prevents the occurrence of kinks in the tubular body 10 as will be described later, it is preferable to use a spring material having a high elastic restoring force.

  The tubular body 10 includes a second reinforcing layer 80 formed by winding a second reinforcing wire 82 in a circular cross section outside the holding wire 70. The second reinforcing layer 80 of the present embodiment is a blade layer in which fine metal wires are braided in a mesh shape. That is, the tubular main body 10 of the present embodiment includes three metal layers, that is, the wire reinforcing layer 30, the holding wire 70, and the second reinforcing layer 80.

  The second reinforcing layer 80 is a member that imparts bending elasticity to the tubular main body 10 together with the wire reinforcing layer 30. It is preferable that the tubular body 10 is elastically restored when the distal portion DE of the tubular body 10 is bent by the pulling operation of the operation line 60 and then the tensile load of the operation line 60 is removed. For this reason, it is preferable that the tubular main body 10 of this embodiment uses a spring metal material for the wire reinforcing layer 30 (reinforcing wire 32) and the second reinforcing layer 80 (second reinforcing wire 82). Therefore, the ductility of the holding wire 70 is higher than any of the ductility of the reinforcing wire 32 and the second reinforcing wire 82.

  A distal portion DE of the tubular body 10 is provided with a first marker 14 and a second marker 16 located on the proximal side of the first marker 14. The first marker 14 and the second marker 16 are ring-shaped members made of a material that does not transmit radiation such as X-rays such as platinum. By using the positions of the two markers of the first marker 14 and the second marker 16 as an index, the position of the distal end of the tubular body 10 in the body cavity (blood vessel) can be visually confirmed under radiation (X-ray) observation. Thereby, the optimal timing for performing the bending operation of the catheter 100 can be easily determined.

  The distal end portion of the operation line 60 is fixed to a portion of the tubular body 10 that is more distal than the second marker 16. By pulling the operation line 60, the distal portion of the distal portion DE with respect to the second marker 16 is bent. In the catheter 100 of the present embodiment, the distal end portion of the operation line 60 is fixed to the first marker 14. The mode of fixing the operation line 60 to the first marker 14 is not particularly limited, and examples thereof include solder bonding, heat fusion, adhesion with an adhesive, and mechanical engagement between the operation line 60 and the first marker 14. .

The inner diameter of the second marker 16 is larger than the inner diameter of the first marker 14. The 1st marker 14 is arrange | positioned so that the outer surface of the wire reinforcement layer 30 may be contacted or it may contact substantially. The inner diameter of the first marker 14 is larger than the outer diameter of the wire reinforcing layer 30 and smaller than the inner diameter of the second reinforcing layer 80.
The positional relationship in the radial direction between the inner wall surface and outer peripheral surface of the first marker 14 and the sub-tube 40 is not particularly limited. When the operation line 60 is fixed to the outer peripheral surface of the first marker 14, the first marker 14 is positioned so that the outer peripheral surface of the first marker 14 is located inside the position where the tip of the subtube 40 is disposed as shown in FIG. 1. An outer diameter of 14 can be set. In addition, when the operation line 60 is fixed to the end surface on the proximal end side of the first marker 14, the end surface may overlap with the distal end of the subtube 40 in the radial direction. In this case, the outer peripheral surface of the first marker 14 may be located on the outer diameter side with respect to the arrangement position of the tip of the subtube 40.
The 2nd marker 16 is arrange | positioned so that the outer surface of the 2nd reinforcement layer 80 may be contacted or it may contact substantially. The inner diameter of the second marker 16 is larger than the outer diameter of the second reinforcing layer 80.

  As shown in FIG. 2, the distal end of the wire reinforcing layer 30 reaches the region where the first marker 14 is disposed. The arrangement region of the first marker 14 is a length region in which the first marker 14 is formed when viewed in the axial direction of the tubular main body 10. The same applies to the second marker 16. The distal end of the wire reinforcing layer 30 is located on the distal side of the tubular body 10 with respect to the proximal end of the first marker 14. Further, the distal end of the wire reinforcing layer 30 is located in the vicinity of the distal end of the first marker 14. In this way, the wire reinforcing layer 30 reaches the region where the first marker 14 is disposed, so that the discontinuity of the bending rigidity of the tubular body 10 at the proximal end of the first marker 14 is alleviated and the kink Occurrence is prevented.

  The distal end of the second reinforcing layer 80 is more proximal than the proximal end of the first marker 14 and more distal than the proximal end of the region where the second marker 16 is disposed. The distal end of the second reinforcing layer 80 is located in the vicinity of the distal end of the second marker 16. Thereby, a discontinuity is generated in the bending rigidity of the tubular body 10 at the distal end of the second marker 16. For this reason, when the operation line 60 is pulled, the tubular body 10 can be sharply bent slightly on the distal side of the second marker 16. Even if the tubular body 10 is bent sharply as described above, the wire reinforcing layer 30 is continuously formed up to the region where the first marker 14 is disposed as described above, and thus the tubular body 10 is kinked. There is nothing. In other words, one of the wire reinforcing layer 30 and the second reinforcing layer 80 is continuously formed to the vicinity of the distal end of the tubular body 10 to prevent kinking, and the other is terminated in the middle of the distal portion DE. The bending position is clearly defined by causing a discontinuity of bending rigidity in the main body 10.

  The proximal ends of the wire reinforcing layer 30 and the second reinforcing layer 80 are located at the proximal end of the tubular body 10, that is, inside the operation portion 90.

  The distal end of the inner layer 24 may reach the distal end of the tubular body 10 or may terminate proximally relative to the distal end. The position where the inner layer 24 terminates may be inside the region where the first marker 14 is disposed.

Here, as described above, the catheter 100 includes the first marker (marker) 14 made of a radiopaque material.
The distal end of the sub-lumen 42, that is, the distal end of the sub-tube 40, terminates at a position overlapping the first marker 14 or a position proximal to the first marker 14 in the distal proximal direction of the tubular body 10. ing. FIG. 1 shows an example in which the proximal end of the first marker 14 and the distal end of the sub-tube 40 are coincident.
Further, as described above, the sliding resistance between the peripheral wall of the sub-lumen 42 (that is, the inner peripheral surface of the sub-tube 40) and the operation line 60 is greater at the distal end than at the intermediate portion of the tubular body 10. High sliding resistance. In other words, the sliding resistance in the length region of at least a part of the distal end portion of the tubular body 10 is larger than the sliding resistance in the intermediate portion of the tubular body 10. Here, in the case of this embodiment, the length region of at least a part of the distal end portion is the length of a portion having a smaller diameter than the sub tube 40 in the intermediate portion of the sub tube 40 at the distal end portion.
In the case of this embodiment, as shown in FIG. 1, the length of the at least part of the length region at the distal end portion of the tubular body 10 is the first marker 14 in the distal base end direction of the tubular body 10. Longer than the length.
Thereby, the sliding resistance between the operation line 60 and the peripheral wall of the auxiliary lumen 42 can be increased in a sufficiently long region.

In addition, this invention is not limited to said embodiment, The deformation | transformation in the range which can achieve the objective of this invention, improvement, etc. are included in this invention.
In the above embodiment, the wire reinforcing layer 30 is a blade layer, and the first outer layer 52 is impregnated from the periphery of the subtube 40 into the inside of the openings of the wire reinforcing layer 30, so that the inner layer 24, the wire reinforcing layer 30, and The sub-tube 40 is exemplified as being integrally fixed. Instead, the first outer layer 52 corresponding to the inner layer of the outer layer 50 may not be substantially impregnated between the wire reinforcing layer 30 and the subtube 40.

  The hydrophilic layer formed on the outer surface of the second outer layer 54 constitutes the outermost layer of the catheter 100. The hydrophilic layer may be formed over the entire length of the tubular body 10 or may be formed only in a partial length region on the tip side including the distal portion DE. The hydrophilic layer is made of, for example, a maleic anhydride polymer such as polyvinyl alcohol (PVA) or a copolymer thereof, or a hydrophilic resin material such as polyvinyl pyrrolidone.

The typical dimension of the component of the catheter 100 of this embodiment is demonstrated.
The diameter of the main lumen 20 can be 400 μm to 600 μm (including an upper limit value and a lower limit value, the same applies hereinafter), the inner layer 24 can have a thickness of 5 μm to 30 μm, and the outer layer 50 can have a thickness of 10 μm to 200 μm. The thickness of the subtube 40 is thinner than the inner layer 24 and can be 1 μm to 10 μm. The inner diameter of the wire reinforcing layer 30 is 410 μm to 660 μm, the outer diameter of the wire reinforcing layer 30 is 450 μm to 740 μm, the inner diameter of the second reinforcing layer 80 is 560 μm to 920 μm, and the outer diameter of the second reinforcing layer 80 is 600 μm to 940 μm. Can do.
The inner diameter of the first marker 14 may be 450 μm to 740 μm, the outer diameter of the first marker 14 may be 490 μm to 820 μm, the inner diameter of the second marker 16 may be 600 μm to 940 μm, and the outer diameter of the second marker 16 may be 640 μm to 960 μm. . The width dimension of the first marker 14 (the dimension in the longitudinal direction of the tubular body 10) can be 0.3 mm to 2.0 mm, and the width dimension of the second marker 16 can be 0.3 mm to 2.0 mm.
The radius (distance) from the axial center of the catheter 100 to the center of the subtube 40 can be 300 μm to 450 μm, the inner diameter (diameter) of the subtube 40 can be 40 μm to 100 μm, and the thickness of the operation line 60 can be 25 μm to 60 μm. .
The tubular body 10 has a diameter of 700 μm to 980 μm, that is, an outer diameter of less than 1 mm, and can be inserted into a blood vessel such as a celiac artery.

When one of the two operation lines 60 included in the catheter 100 is pulled toward the proximal end side, a tensile force is applied to the distal end portion of the catheter 100 via the one operation line 60. Given. Thereby, the distal portion DE of the tubular body 10 is bent toward the side of the sub-tube 40 through which the one operation line 60 is inserted, with the axis of the tubular body 10 as a reference. In addition, when the other operation line 60 is pulled toward the proximal end side, a tensile force is applied to the distal portion DE of the catheter 100 via the other operation line 60. As a result, the distal portion DE of the tubular body 10 is bent toward the side of the sub-tube 40 through which the other operation line 60 is inserted, with the axis of the tubular body 10 as a reference.
Here, the bending of the tubular main body 10 includes an aspect in which the tubular main body 10 is bent in an “L-shape” and an aspect in which the tubular main body 10 is bent like a bow.

According to the first embodiment as described above, as described above, the sliding resistance between the peripheral wall of the sub-lumen 42 (inner peripheral surface of the sub-tube 40) and the operation line 60 is the intermediate portion of the tubular body 10. The sliding resistance at the tip of the tubular body 10 is greater than the sliding resistance at.
Thereby, since it can suppress that the front-end | tip part of the tubular main body 10 bends locally with an excessive curvature (excessive curvature radius), while being able to adjust the direction of the front-end | tip of the tubular main body 10 easily, the tubular main body 10 It is easy to allow the tip of the body to enter a desired body cavity.
That is, the operability of the catheter 100 can be improved.

Here, in the conventional intravascular catheter, when the operation line is pulled, first, the whole and the distal end are bent. The intermediate part and the base end part are held to some extent by a blood vessel (thick blood vessel at the branching source) or the parent catheter, and the distal end portion is bent at the branching portion (thin blood vessel) of the blood vessel. With the tip bent about 90 degrees, point the tip to the target branch vessel and push the catheter as it is, so the tip is only slightly caught on the branch vessel, so the entire catheter is inside the large vessel. The force that travels straight will be lost, and the tip will fall off the branch vessel.
And, when the catheter is pushed in while increasing the pulling length of the operation line in the state where the bent distal end is hooked on the branch blood vessel, the intermediate portion bends into the branch blood vessel following the distal end of the catheter. It is considered that the catheter can be successfully entered into the target branch vessel. However, when the pulling length of the operation line is increased in this way, the curvature of the distal end becomes excessive when the intermediate portion of the catheter is bent. When the bending angle of the distal end portion is 180 degrees, the distal end portion is directed to the proximal end side (that is, the branching source side when viewed from the branch blood vessel), and when the catheter is pushed in, the tip portion is easily dropped from the branch blood vessel.

On the other hand, in the catheter 100 according to the present embodiment, the force pulling the operation line 60 is consumed by the sliding resistance at the distal end portion of the tubular main body 10, so that the traction force applied to the distal end portion is suppressed. For this reason, while being able to suppress that the front-end | tip part of the tubular main body 10 bends locally with an excessive curvature (excessive curvature radius), the range containing a front-end | tip part and an intermediate part can be bent gently. .
Therefore, by pushing the catheter 100 in a state where the distal end of the tubular body 10 is hooked on the branch blood vessel, the catheter 100 can be easily advanced in the target direction without dropping off the branch blood vessel.

Here, the mechanism will be described with reference to FIGS.
FIG. 4 is a schematic diagram for explaining the behavior of the catheter 100 according to the embodiment. Among these, (a) and (b) are moment (a) when the curvature of the tubular body 10 is small and the distal end of the tubular body 10. The accumulated value (b) obtained by integrating the moment from the (distal end) toward the hand (base end) side is shown, and (c) and (d) are the moment (a) and accumulated when the curvature of the tubular body 10 is large. Value (b) is shown.
On the other hand, FIG. 5 is a schematic diagram for explaining the behavior of the catheter according to the comparative embodiment. Among these, (a) and (b) are moment (a) and cumulative value (b) when the curvature of the tubular body 10 is small. (C) and (d) show the moment (a) and cumulative value (b) when the curvature of the tubular body 10 is large.
The catheter according to the comparative embodiment is different from the catheter 100 according to the embodiment in that the diameter of the sub-tube 40 at the distal end is the same as the diameter of the sub-tube 40 at the intermediate portion. It is comprised similarly to the catheter 100 which concerns.

  As shown in FIGS. 4 (a) and 4 (b) and FIGS. 5 (a) and 5 (b), when the curvature of the tubular body 10 is small (when the force pulling the operation line 60 is weak), this In both the embodiment and the comparative embodiment, since the rubbing between the peripheral wall of the sub-lumen 42 and the operation line 60 does not substantially occur, a moment acts locally only on the tip portion, and only the tip portion is bent locally. (But the curvature is small).

  On the other hand, as shown in FIGS. 4C and 4D, in the case of this embodiment, when the curvature of the tubular body 10 is large (when the force pulling the operation line 60 is strong), the auxiliary lumen 42 is used. Since the rubbing between the peripheral wall and the operation line 60 occurs, the moment acts by being dispersed from the front end portion to the intermediate portion (corresponding to the region where the dashed-dotted rectangular frame is disposed), and from the front end portion to the intermediate portion. The tubular body 10 is bent gently.

  However, as shown in FIGS. 5C and 5D, when the curvature of the tubular body 10 is large (when the force pulling the operation line 60 is strong), the moment is concentrated at the tip portion in the comparative embodiment. However, the tip portion is mainly bent.

  Here, a method for measuring the sliding resistance between the inner peripheral surface of the sub-tube 40 (the peripheral wall of the sub-lumen 42) and the operation line 60 will be described with reference to FIG.

  First, the tubular body 10 is cut out from the distal end portion and the intermediate portion of the catheter, and the tubular body 10 is bent and fixed. In addition, the length of the tubular body 10 cut out from the tip portion and the length of the tubular body 10 cut out from the intermediate portion are equal to each other (hereinafter, this length is referred to as a predetermined length). Also, the bent shape of the tubular body 10 cut out from the tip portion and the bent shape of the tubular body 10 cut out from the middle portion are made equal to each other. It should be noted that both ends of the tubular body 10 cut out longer than the predetermined length (without cutting the operation line 60) are cut out so that the operation lines 60 protrude from both ends of the tubular body 10 having a predetermined length. A tubular body 10 having a predetermined length is prepared. It is assumed that the operation line 60 protruding from both ends of the tubular body 10 protrudes from the common auxiliary lumen 42.

Next, the tip of the operation line 60 that protrudes from one end of the cut-out tubular body 10 is fixed to a load cell (not shown), and the tip of the operation line 60 that protrudes from the other end of the cut-out tubular body 10 passes through the pulley 130. The weight 140 is fixed to the weight 140, and the weight 140 is suspended from the pulley 130.
In this state, one end of the operation line 60 is pulled by the load cell, and the traction load at that time is measured. A value obtained by subtracting the load due to the weight of the weight 140 (the integrated value of the weight of the weight 140 and the acceleration of gravity) from the measured pulling load is measured as the sliding resistance.

[Second Embodiment]
FIG. 6 is a longitudinal sectional view of the catheter 100 according to the second embodiment.
In the case of the present embodiment, the adhesion of the operation line 60 to the peripheral wall of the sub-lumen 42 is stronger at the distal end of the tubular body 10 than at the middle of the tubular body 10.
As a result, the sliding resistance between the peripheral wall of the sub-lumen 42 and the operation line 60 is larger at the distal end than at the intermediate portion.
Here, the adhesion of the operation line 60 to the peripheral wall of the secondary lumen 42 is a property having a positive correlation with the dynamic friction coefficient between the peripheral wall of the secondary lumen 42 and the operation line 60.
The adhesion of the operation line 60 to the peripheral wall of the secondary lumen 42 is determined according to the resin material or the like constituting the peripheral wall. For this reason, by making the resin material constituting the peripheral wall of the sub-lumen 42 different between the distal end portion and the intermediate portion, the adhesiveness at the distal end portion of the tubular main body 10 is more than the adhesiveness at the intermediate portion of the tubular main body 10. A strong configuration can be realized.

In the case of the present embodiment, as shown in FIG. 6, the tip of the sub-tube 40 terminates at the intermediate portion of the tubular body 10.
The sub-lumen 42 includes a first portion 42a formed by the internal space of the subtube 40, and a second portion formed in the tubular body 10 on the distal end side of the subtube 40 and communicating with the first portion 42a. 42b.
The peripheral wall of the second portion 42b of the sub-lumen 42 is constituted by, for example, the outer layer 50, and more specifically, for example, constituted by the first outer layer 52 (see FIG. 2). The inner diameter of the second portion 42b is smaller than the inner diameter of the first portion 42a.
The adhesion of the operation line 60 to the constituent material of the outer layer 50 is stronger than the adhesion of the operation line 60 to the constituent material of the subtube 40.
Therefore, a configuration is realized in which the sliding resistance between the peripheral wall of the sub-lumen 42 and the operation line 60 is larger in sliding resistance in the distal end portion than in the intermediate portion.

  The catheter 100 according to the present embodiment is the same as the first embodiment with respect to other configurations, and thus the description thereof is omitted.

[Third Embodiment]
FIG. 7 is a longitudinal sectional view of the catheter 100 according to the third embodiment.
Also in this embodiment, the adhesion of the operation line 60 to the peripheral wall of the secondary lumen 42 is stronger at the distal end of the tubular body 10 than at the intermediate portion of the tubular body 10. The sliding resistance between the peripheral wall of the lumen 42 and the operation line 60 is larger at the tip than at the intermediate portion.

In the case of the present embodiment, as shown in FIG. 7, the sub-tube 40 includes a first tube 40 a located in the middle portion of the tubular body 10 and a distal end portion of the tubular body 10 connected to the distal end side of the first tube 40 a. 2nd tube 40b located in this.
The first tube 40a and the second tube 40b are made of different materials. That is, the adhesion of the operation line 60 to the constituent material of the second tube 40b is stronger than the adhesion of the operation line 60 to the constituent material of the first tube 40a.
Therefore, a configuration is realized in which the sliding resistance between the peripheral wall of the sub-lumen 42 and the operation line 60 is larger in sliding resistance in the distal end portion than in the intermediate portion.

  The catheter 100 according to the present embodiment is the same as the first embodiment with respect to other configurations, and thus the description thereof is omitted.

[Fourth Embodiment]
FIG. 8 is a longitudinal sectional view of the catheter 100 according to the fourth embodiment. In FIG. 8, as in FIG. 3, illustration of a part of the configuration of the catheter 100 is omitted.
Also in this embodiment, the adhesion of the operation line 60 to the peripheral wall of the secondary lumen 42 is stronger at the distal end of the tubular body 10 than at the intermediate portion of the tubular body 10. The sliding resistance between the peripheral wall of the lumen 42 and the operation line 60 is larger at the tip than at the intermediate portion.

  In the case of the present embodiment, an opening 41 penetrating the inside and outside of the subtube 40 is formed in the subtube 40 at the distal end portion of the tubular body 10. The constituent material of the tubular body 10 protrudes into the subtube 40 through the opening 41. More specifically, the constituent material of the outer layer 50 (in particular, for example, the first outer layer 52 (FIG. 2)) protrudes into the subtube 40 through the opening 41. Due to the presence of the resin material protruding into the sub-tube 40 through the opening 41, the sliding resistance at the tip is increased. As a result, a configuration is realized in which the sliding resistance between the peripheral wall of the auxiliary lumen 42 and the operation line 60 is larger at the distal end than at the intermediate portion.

  The catheter 100 according to the present embodiment is the same as the first embodiment with respect to other configurations, and thus the description thereof is omitted.

[Fifth Embodiment]
FIG. 9 is a longitudinal sectional view of a catheter 100 according to the fifth embodiment. 9, illustration of a part of the structure of the catheter 100 is omitted as in FIG.
As shown in FIG. 9, in the case of the present embodiment, unevenness (small unevenness) is formed on the inner surface of the sub-tube 40 at the distal end portion of the tubular main body 10. On the other hand, in the intermediate part of the tubular body 10, the inner surface of the sub-tube 40 is formed smoothly (at least more smoothly than the tip part).
More specifically, for example, when the sub tube 40 is compressed in the axial direction, the sub tube 40 is formed in a bellows shape at the distal end portion of the tubular body 10, and as a result, the inner surface and the outer surface of the sub tube 40 are uneven 47. Is formed.
As a result, a configuration is realized in which the sliding resistance between the peripheral wall of the sub-lumen 42 and the operation line 60 is larger at the distal end than at the intermediate portion.

  The present invention is not limited to the above-described embodiment, and includes various modifications and improvements as long as the object of the present invention is achieved.

  It should be noted that the various components of the present invention need not be individually independent. A plurality of components are formed as one member, a component is formed of a plurality of members, one component is a part of another component, and one component is And a part of other components are allowed to overlap.

The above embodiment includes the following technical idea.
(1) a sheath body, a lumen formed in the inside of the sheath body, and an operation line that is inserted through the lumen and connected to a distal end portion of the sheath body. A catheter in which the tip is bent by pulling a wire,
The sliding resistance between the peripheral wall of the lumen and the operation line is greater at the distal end than at the intermediate portion between the distal end and the proximal end of the sheath body. catheter.
(2) The catheter according to (1), wherein an inner diameter of the lumen at the distal end portion is smaller than an inner diameter of the lumen at the intermediate portion.
(3) comprising a tube embedded in the sheath body;
The inner space of the tube constitutes the lumen;
The catheter according to (2), wherein the tube is crushed at the distal end portion.
(4) comprising a tube embedded in the sheath body;
The inner space of the tube constitutes the lumen;
The catheter according to any one of (1) to (3), wherein an unevenness is formed on an inner surface of the tube at the distal end portion.
(5) The adhesiveness of the operation line with respect to the peripheral wall of the lumen is the adhesiveness according to any one of (1) to (4), wherein the adhesiveness at the distal end is stronger than the adhesiveness at the intermediate portion. catheter.
(6) a tube embedded in the sheath body,
The tip of the tube terminates at the intermediate portion,
The lumen is
A first portion constituted by an internal space of the tube;
A second portion formed in the sheath body on the tip side of the tube and communicating with the first portion;
The catheter according to (5), comprising:
(7) A tube embedded in the sheath body is provided,
The inner space of the tube constitutes the lumen;
The tube
A first tube located in the intermediate portion;
A second tube connected to the distal end side of the first tube and positioned at the distal end;
Including
The catheter according to (5), wherein the first tube and the second tube are made of different materials.
(8) comprising a tube embedded in the sheath body;
The inner space of the tube constitutes the lumen;
In the tip portion, an opening penetrating the inside and outside of the tube is formed,
The catheter according to (5), wherein the constituent material of the sheath body protrudes into the tube through the opening.
(9) comprising a marker made of a radiopaque material;
The distal end of the lumen terminates at a position overlapping the marker or a position proximal to the marker in the distal proximal direction of the sheath body,
The sliding resistance in the length region of at least a part of the tip is larger than the sliding resistance in the intermediate portion;
The catheter according to any one of (1) to (8), wherein a length of the at least part of a length region at the distal end portion is longer than a length of the marker in a distal proximal direction of the sheath body. .

10 Tubular body (sheath body)
14 First marker 16 Second marker 20 Main lumen 24 Inner layer 30 Wire reinforcing layer 32 Reinforcing wire 40 Subtube (tube)
40a 1st tube 40b 2nd tube 41 Opening 42 Sublumen 42a 1st part 42b 2nd part 50 Outer layer 52 1st outer layer 54 2nd outer layer 60 Operation line 70 Holding wire 80 2nd reinforcement layer 82 2nd reinforcement wire 100 Catheter 130 Pulley 140 Weight DE Distal part

Claims (9)

A sheath body; a lumen formed in the sheath body; and an operation line inserted through the lumen and connected to a distal end of the sheath body, the operation line being pulled A catheter that bends the tip by being
The sliding resistance between the peripheral wall of the lumen and the operation line is greater at the distal end than at the intermediate portion between the distal end and the proximal end of the sheath body. catheter.   The catheter according to claim 1, wherein an inner diameter of the lumen at the distal end portion is smaller than an inner diameter of the lumen at the intermediate portion. Comprising a tube embedded in the sheath body;
The inner space of the tube constitutes the lumen;
The catheter according to claim 2, wherein the tube is crushed at the distal end portion. Comprising a tube embedded in the sheath body;
The inner space of the tube constitutes the lumen;
The catheter according to any one of claims 1 to 3, wherein unevenness is formed on an inner surface of the tube at the distal end portion.   The catheter according to any one of claims 1 to 4, wherein the adhesion of the operation line to the peripheral wall of the lumen is stronger in the adhesion at the distal end than at the adhesion at the intermediate portion. Comprising a tube embedded in the sheath body;
The tip of the tube terminates at the intermediate portion,
The lumen is
A first portion constituted by an internal space of the tube;
A second portion formed in the sheath body on the tip side of the tube and communicating with the first portion;
The catheter according to claim 5. Comprising a tube embedded in the sheath body;
The inner space of the tube constitutes the lumen;
The tube
A first tube located in the intermediate portion;
A second tube connected to the distal end side of the first tube and positioned at the distal end;
Including
The catheter according to claim 5, wherein the first tube and the second tube are made of different materials. Comprising a tube embedded in the sheath body;
The inner space of the tube constitutes the lumen;
In the tip portion, an opening penetrating the inside and outside of the tube is formed,
The catheter according to claim 5, wherein the constituent material of the sheath body protrudes into the tube through the opening. With markers made of radiopaque material,
The distal end of the lumen terminates at a position overlapping the marker or a position proximal to the marker in the distal proximal direction of the sheath body,
The sliding resistance in the length region of at least a part of the tip is larger than the sliding resistance in the intermediate portion;
The catheter according to any one of claims 1 to 8, wherein a length of the at least part of a length region in the distal end portion is longer than a length of the marker in a distal proximal direction of the sheath body.

Images