WO2006093274A1

WO2006093274A1 - Vascular catheter and method of producing the same

Info

Publication number: WO2006093274A1
Application number: PCT/JP2006/304106
Authority: WO
Inventors: Tetsuya Nakamatsu; Keiichi Kagami; Hirofumi Mizoguchi; Tatsumichi Fujiwara; Jiro Hara
Original assignee: Goodman Co., Ltd.
Priority date: 2005-03-03
Filing date: 2006-03-03
Publication date: 2006-09-08
Also published as: JP5027651B2; JP2011212493A; JPWO2006093274A1

Abstract

[PROBLEMS] To provide a vascular catheter which can prevent damages in the vascular wall of a blood vessel, etc. during delivery while maintaining a favorable delivery performance toward an affected part and surely pass through the affected part. [MEANS FOR SOLVING PROBLEMS] A vascular catheter (blood vessel catheter) (C1) having a tubular chip (4) being more flexible than the basal side thereof at the leading end of a main catheter body (7) having a side lumen (10) and a main lumen (11) in the interior thereof. At the leading end of this chip (4), a shape-retaining member (5), which retains the shape of the opening of the main lumen (11) located at the front end of the chip (4) against a radial external force without worsening the bendability of the chip (4) in the major axis direction, is provided.

Description

Specification

Vascular catheter and method for manufacturing the same

Technical field

The present invention relates to a vascular catheter that is inserted into a blood vessel including a blood vessel, and a manufacturing method thereof.

Background art

[0002] As a catheter inserted into a living body lumen (especially for treatment of common bile duct stones by EPBD), one described in Patent Document 1 below is known. In this catheter, when pulling the gripping part that holds the stone, the tip tends to tear in the circumferential direction.

A metal ring as a reinforcing material is attached to the tip (paragraph 0015).

Patent Document 1: Japanese Patent Laid-Open No. 2001-149377

Disclosure of the invention

Problems to be solved by the invention

However, if such a catheter is applied as it is, for example, for blood vessels, the following problems may occur. That is, in the vascular catheter, the most advanced portion (chip) is configured to be particularly flexible in order to prevent damage to the blood vessel. On the other hand, the blood vessel is bent in a complex manner, and the inner diameter of the affected blood vessel may become narrow due to stenosis. Moreover, the affected part may be hardened by calcification. When delivering a dilatation balloon catheter along such a guide wire to such an affected area, if the bend radius of the blood vessel is small, the tip of the tip will be deformed vertically to the outside of the bend radius, preventing the catheter tip from tearing. Even if a ring is provided, the tip shape is deformed in the radial direction, the tip tip is lifted from the guide wire (part x in Fig. 10), and the tip tip hits the vessel wall. However, there is a possibility of damaging the vessel wall.

[0004] In addition, when the blood vessel inner diameter of the affected part is narrow or hardened by calcification, when the tip of the tip hits the affected part, the tip of the tip is crushed and pulled, and the affected part passes through the affected part. There is a possibility that you can not pass ^ fe.

[0005] Therefore, the present invention has been made in view of such circumstances, and its purpose is to apply to the affected area. An object of the present invention is to provide a vascular catheter that can prevent damage to a vascular wall such as a blood vessel during delivery while maintaining delivery performance, and can reliably pass an affected area, and a method for manufacturing the same.

Means for solving the problem

[0006] In order to achieve the above object, the invention of claim 1 is characterized in that a distal end portion of a catheter body having a lumen therein is provided with a tubular tip having a higher flexibility than the proximal end side. In a tube catheter, a shape maintaining body that maintains the opening shape of the tip end lumen of the tip against the external force in the radial direction is disposed on the tip side of the tip without damaging the flexibility in the long axis direction of the tip. It is characterized by doing.

[0007] Further, the inventions of claims 2 and 3 achieve the object of further securing the flexibility in the long axis direction and the rigidity in the radial direction. In the above invention, at least a part of the high-strength resin or composite resin is formed into a thread shape. It is characterized by.

[0008] Furthermore, in addition to the above object, in order to achieve the purpose of adjusting the flexibility in the major axis direction and the rigidity in the radial direction, the invention according to claim 4 is characterized in that in the above invention, the coiled shape is At least a part of the shape maintaining body is a double row wound coil made of different materials, and the invention according to claim 5 is the above invention, wherein the shape maintaining body is at least two layers or more. It is characterized by the layer structure. In addition to the above object, in order to achieve the object of further improving safety and operability, the invention according to claim 6 is characterized in that, in the above invention, the shape maintaining body is an inner surface or an outer surface of a tip portion of the chip. 8. The invention according to claim 7, wherein the shape maintaining body is covered with a cover disposed inside or outside a tip portion of the chip. Is arranged inside the chip.

[0009] On the other hand, in order to achieve the above object, an invention according to claim 8 is a method of manufacturing a vascular catheter including a catheter main body provided with a lumen therein, and is provided outside the core material. A coating material having a lower melting point than the core material is coated to form a coated core material, and the coated core material is spirally wound so that the temperature is equal to or higher than the melting point of the coating material and lower than the melting point of the core material. Covered The sheath material is heated to form the catheter body in a state including the shape maintaining body as a spiral core material. Is a method of manufacturing a vascular catheter having a cylindrical tip that is more flexible than the proximal end side at the distal end portion of the catheter body, and is flexible in the longitudinal direction of the tip. The core material has a low melting point on the outside of the core material to form the shape maintaining body that maintains the opening shape of the lumen at the tip of the tip against the external force in the radial direction without impairing the performance. To form a coated core material, and then winding the coated core material in a spiral shape, heating the coated core material to a temperature not lower than the melting point of the coating material and lower than the melting point of the core material, The chip includes the shape maintaining body as a spiral core material The invention according to claim 10 is characterized in that in the above invention, a heat-shrinkable tube that shrinks by heating is externally attached to the coated core material that is spirally wound. It is characterized by pressurizing the said covering core material at the time of a heating.

The invention's effect

[0010] In the vascular catheter of the present invention, at the time of delivery to the affected area, the shape maintaining body has flexibility in the length direction, and therefore, even in a blood vessel having a small bending radius, the tip extends along the guide wire. While it can follow flexibly, it has rigidity in the radial direction. Therefore, the leading edge of the tip can be suppressed to prevent blood vessel damage, and the tip of the tip can be surely passed without being crushed in a hard affected part that has been calcified or an affected part with a narrow blood vessel inner diameter due to stenosis. It is extremely useful as a medical device with high operability and safety. Moreover, in the method for producing a vascular catheter of the present invention, such a useful vascular catheter can be formed very efficiently.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate.

[0012] [First embodiment according to vascular catheter]

FIG. 1 (a) is a longitudinal sectional view of the distal side of a vascular catheter (an vascular catheter as an example) (C1) according to the first embodiment of the present invention, and FIG. 1 (b) is an A-A line. It is sectional drawing.

As shown in FIG. 1, the vascular catheter (C1) has a catheter body (7) including an inner tube (2) and an outer tube (3) including the inner tube (2) on the inner tube (2). Innerchi The outside of the tube (2) and the inside of the outer tube (3) has a secondary lumen (10), and the inside of the inner tube (2) has a main lumen (11).

[0014] The tip of the inner tube (2) protrudes slightly from the tip of the outer tube (3), and the inner tube (2) extends from the outer periphery of the tip edge to the outer periphery of the outer tube (3). ) Is attached. An X-ray opaque marker (9) indicating the effective length of the balloon (1) is installed on the outer periphery of the inner tube (2) inside the balloon (1).

[0015] In addition, at the tip of the inner tube (2), a cylindrical tip (4) having higher flexibility than the inner tube (2) has a main lumen (11) continuously from the inner tube (2). It is attached with. The tip (4) is a short member that is shorter than the effective length of the balloon (1), and has an outer surface that is continuous from the tip of the inner tube (2) and is tapered.

[0016] Then, a ring-shaped shape maintaining body (5) as shown in FIG. 2 (a) is arranged on the tip side (the most advanced portion) of the tip (4). The material of the shape maintaining body (5) is gold or platinum or an alloy containing these as a main component, stainless steel, polyimide or other high-strength resin (including hard resin), or a resin mixed with carbon nanotubes (carbon nanotubes as fillers). This is a composite material and is extremely rigid, so even a small member has sufficient rigidity in the radial direction and receives external force in the radial direction due to bending during delivery. Even if the ring shape collapses into an ellipse, the original shape is maintained. Further, since the shape maintaining body (5) is not crushed, the tip opening shape of the main lumen (11) in the tip (4) is maintained. On the other hand, since the shape maintaining body (5) is ring-shaped, the flexibility in the major axis direction of the tip (4) is not impaired.

[0017] Then, the tip of the vascular force tape (C1) is manufactured by embedding the shape maintaining body (5) in the tip (4) as follows. In other words, an enlarged diameter portion is formed inside the tip of the tip (4) so that the cylindrical cover (6) is just inserted, and the outside of the cover (6) and the tip (4) are expanded. The shape maintaining body (5) is covered with the cover (6) by sandwiching the shape maintaining body (5) with the inside of the diameter portion.

[0018] In the above vascular catheter (C1), the internal lumen (10) and the main lumen (11) The tip of the catheter body (7) having a tip is provided with a tip (4) that is more flexible than the base end, and the tip (4) of the tip (4) is provided at the tip of the tip (4). A shape maintaining body (5) that maintains the opening shape of the tip (4) leading-edge main lumen (11) against the external force in the radial direction without losing flexibility in the long axis direction. Therefore, as shown in FIG. 6, even when a blood vessel (P) having a small bending radius is passed over the guide wire (G), the opening of the main lumen (11) does not spread out. It is possible to prevent the blood vessel from being damaged by the portion, and also to prevent the situation where the hardened portion and the small diameter portion cannot pass due to the protruding portion being applied, and the safety and operability can be made extremely high.

In addition, the shape maintaining body (5) is disposed on the inner surface of the tip portion of the chip (4) and is covered with a cover (6) disposed on the inner side of the tip portion of the chip (4). Therefore, the highly rigid shape maintaining body (5) is not exposed, and the safety can be further improved.

[0020] [Second embodiment according to vascular catheter]

FIG. 3 is a longitudinal sectional view of the distal end side of the vascular catheter (C2) according to the second embodiment of the present invention. This vascular catheter (C2) is different from the vascular catheter (C1) according to the first embodiment only in the arrangement of the shape maintaining body and the configuration of the cover. That is, the shape maintaining body (5) of the vascular force tape (C2) is disposed on the outer surface of the tip diameter-reduced portion of the tip (4) and the tip contraction portion is disposed on the outer side of the tip diameter-reduced portion. It is covered with a cover (6a) that fits in the diameter. Such a cover (6a) can also form a vascular catheter with high safety and operability.

[0021] [Other Embodiments Related to Vascular Catheter]

Subsequently, each embodiment obtained by changing only the shape maintaining body in the above embodiment will be described.

That is, the shape maintaining body has a ring shape that is partially broken as shown in FIG. 2 (b). Further, the shape maintaining body is formed into a short pipe shape as shown in FIG. 4 (a), or a partially cut short pipe shape as shown in FIG. 4 (b). Also by these, it is possible to provide a shape maintaining body that is flexible in the long axis direction and highly rigid in the radial direction.

[0023] Alternatively, the shape maintaining body may be a tightly packed coil as shown in FIG. As shown in Fig. 5 (b), the coil is formed into a rough coil shape with a slight gap, or as shown in Fig. 5 (c), it is composed of a double-row coiled coil made of different materials as a whole. As shown in d), a part of the coil consists of a double-rowed coil made of different materials, as shown in Fig. 5 (e), or a multi-layered structure of different materials, As shown in Fig. 5 (f), a short spiral shape is used. Also by these, it is possible to provide a shape maintaining body that is flexible in the long axis direction and highly rigid in the radial direction. In addition, in the case of adopting a plurality of different materials, the adjustment of the flexibility and rigidity can be adjusted by a combination of materials, a dimensional ratio, or the like.

[0024] It should be noted that the embodiments relating to the vascular catheter of the present invention are not limited to those described above, and the above embodiments can be variously modified as illustrated below. In other words, the material of the shape maintaining body is changed to another material such as a super elastic metal such as nickel titanium. For composite resins, instead of carbon nanotubes, high-strength fibers such as carbon fibers and glass fibers, ceramic powders including carbon powder and silica powder, or the like are mixed appropriately or mixed (resin Of these fillers). Alternatively, the tip is not tapered but has the same diameter over each part. Further, the cover does not fit in the enlarged diameter portion or the reduced diameter portion, and simply covers the shape maintaining body. Alternatively, the shape maintaining body is formed into a thread shape related to a single wire or a stranded wire. Here, as the filamentous shape maintenance body, a filamentous polymer related to a drawn material or a stranded wire may be selected. In addition, the cross-sectional shape of the shape maintaining body, lumen, etc. is an ellipse or a polygon. Alternatively, a balloon force element having a main multiple lumen is introduced into a balloon catheter other than the catheter, or into another vascular catheter.

[Embodiment related to manufacturing method of vascular catheter]

FIG. 7 is an explanatory view of a vascular catheter manufacturing method different from the manufacturing method according to the vascular catheter (Cl, C2) shown in FIG. 1 and FIG. In this manufacturing method, first, the core material (21) is coated with a coating material (22) made of a hot-melt resin having a lower melting point to form a coated core material (23). Next, as shown in FIG. 7 (a), the coated core material (23) is tightly wound in a state along the axis (24). Subsequently, a resin heat-shrinkable tube (25) is put on the coated core material (23). The core material (21) is made of, for example, a metal, resin, or composite resin (resin mixed with filler). It is preferable that the material or the stranded wire thereof, or a combination thereof (a stranded wire of a plurality of materials, etc.) is selected. The coated core material (23) is wound by, for example, manual winding or a winding device related to a general spring manufacturing apparatus or coil manufacturing apparatus.

[0026] Then, the heat-shrinkable tube (25) is heated to a temperature not lower than the melting point (glass transition point) of the covering material (22) and lower than the melting point of the core material (21) by the heating wire (26) disposed on the outside thereof. Heat as shown. The heat-shrinkable tube (25) heats the coating material (22) by this heating to melt the coating material (22), and contracts itself to apply pressure to the coating material (22). Thereafter, heating to the heat-shrinkable tube (25) is stopped so that the heat-shrinkable tube (25) and the like reach a temperature below the melting point of the covering material (22), and the heat-shrinkable tube (25) is removed. Then, as shown in FIG. 7 (b), the spiral core material (21), that is, the shape is maintained inside the cylindrical covering material (22) having a lumen having the same diameter as the shaft (24). A chip (27) on which the body is located is formed. This tip (27) is placed at the tip of the vascular catheter.

[0027] In this method for manufacturing a vascular catheter, a coated core material (23) is formed by coating a coating material (22) having a melting point lower than that of the core material (21) on the outside of the core material (21). At the same time, the coated core material (23) is spirally wound, and the coated core material (23) is heated to a temperature not lower than the melting point of the coated material (22) and lower than the melting point of the core material (21). Since the tip (27) is formed in a state including the shape maintaining body as the spiral core material (21), the cylindrical tip (27) including the shape maintaining body can be efficiently formed. Therefore, it is possible to efficiently provide a vascular catheter that can prevent damage to the vascular wall during delivery while maintaining delivery performance to the affected area, and can also reliably pass the affected area. Has an effect.

[0028] Further, in the manufacturing method described above, the coated core material (23) is heated while being pressurized by covering the spiral coated core material (23) with the heat-shrinkable tube (25). Therefore, melting and aggregation of the coated core material (23) can be adjusted, and therefore, in addition to the above effects, a tip (27) or a vascular catheter that is tougher and more flexible in terms of composition can be provided. The effect of. Further, according to the manufacturing method described above, the shape maintaining body can be arranged inside the tip, that is, it is possible to form a vascular catheter with high safety and operability. [0029] [Other Embodiments Related to Manufacturing Method of Vascular Catheter]

The embodiment according to the method for manufacturing the vascular catheter of the present invention is not limited to the above, and can be variously modified as illustrated below. That is, the coated core material is rolled or heated without using a shaft or a heat shrinkable tube. Roughly coat the coated core. A plurality of coated core materials having mutually different core materials are alternately wound. For the heat source, the shaft is heated, or instead of the heating wire, hot air from a nozzle, a heated mold, a heating tank, a laser, or an appropriate combination thereof is used. Alternatively, the shaft, the shape maintaining body, the heat shrinkable tube, the core material, and the covering material are used, and the cross-sectional shape is an ellipse or polygon, or the cross-sectional size is increased or decreased. Leave the heat-shrinkable tube as it is without removing it. The covering material is made of metal. As a heat source in the case where the shaft is made of metal, a material by induction heating or an appropriate combination with the above is selected.

[0030] On the other hand, also by the method shown in FIG. 8, it is possible to produce the chip S having the shape maintaining body according to the present invention. That is, as shown in FIG. 8 (a), a ring (32) serving as a shape maintaining body is disposed around an axis (30), and a melting tube (34) that melts by heat or pressure is provided outside thereof. Deploy. In addition, a contraction tube (36) is disposed on the outer side as appropriate. Then, the melting tube (34) is melted by heating with a heating wire (38), the ring (32) is put into the melting tube (34), and the heating is stopped. Then, as shown in FIG. 8 (b), a melting tube (34) including a ring (32), that is, a tip including a shape maintaining body is formed.

[0031] In addition, the method shown in FIG. 9 can also be used to produce a chip with a shape maintaining body according to the present invention. That is, as shown in FIG. 9 (a), a chip body (43) that constitutes most of the chip (41) and has a recess (42) on the tip side is disposed around the shaft (40). A ring (44) serving as a shape maintaining body is arranged outside the 42), and the melting tube (45) enters the depression (42) outside the depression (42) or the ring (44) and melts by heat or pressure. ). In addition, a contraction tube (46) is arranged on the outer side as appropriate. Then, the melting tube (45) is melted by heating with a heating wire (48), etc., and the melting tube (45) is put in the state where the ring (44) is inserted into the melting tube (45) and the recess (42). Close contact with the chip body (43) and stop heating. Here, the chip body (43) may be melted together, or may not be melted even when the heating is performed. Then, as shown in Fig. 8 (b), the chip including the ring (32) The main body (43) or the melting tube (45), that is, the tip (41) including the shape maintaining body is formed. In the manufacturing method of FIGS. 8 and 9, the ring may be replaced with the other shape maintaining body. Then, the core material or the ring or the like by the above manufacturing methods can be applied on the proximal end side (other than the tip) of the catheter body, and the core is used for purposes other than maintaining the shape (for example, strength improvement purposes). Can be loaded with materials.

Brief Description of Drawings

FIG. 1 (a) is a longitudinal sectional view of the distal end side of the vascular catheter according to the first embodiment of the present invention, and FIG. 1 (b) is a sectional view taken along line AA.

2 (a) is a perspective explanatory view of a shape maintaining body in the vascular catheter of FIG. 1, and FIG. 2 (b) is a perspective explanatory view of a shape maintaining body according to another embodiment.

FIG. 3 is a longitudinal sectional view of the distal end side of a vascular catheter according to a second embodiment of the present invention.

FIG. 4 (a) to (b) are perspective explanatory views of a shape maintaining body according to another embodiment.

[FIG. 5] (a) to (f) are side explanatory views of a shape maintaining body according to another embodiment.

FIG. 6 is a schematic view when the vascular catheter according to the present invention is introduced into a blood vessel.

FIG. 7 is an explanatory view showing (a) before heating (b) after heating in the method for manufacturing a vascular catheter according to the present invention.

FIG. 8 is an explanatory view showing (a) before heating and (b) after heating in a modified example of the method for manufacturing a vascular catheter according to the present invention.

FIG. 9 is an explanatory view showing (a) before heating and (b) after heating in another modification of the method for manufacturing a vascular catheter according to the present invention.

FIG. 10 is a schematic view when a conventional vascular catheter is introduced into a blood vessel.

Explanation of symbols

[0033] 4, 27, 41 chips

5 Shape maintenance body

6 Cover

7 Catheter body

10 Deputy Noremen Main lumen Core material Cover material Cover material Heat shrink tube

Claims

The scope of the claims

[1] In a vascular catheter provided with a cylindrical tip having a higher flexibility at the distal end portion of the catheter body having a lumen inside than the proximal end side,

A shape holding body that maintains the opening shape of the tipmost lumen of the tip against the external force in the radial direction is disposed on at least the tip side of the tip without damaging the flexibility in the long axis direction of the tip. Characteristic vascular catheter.

[2] The pulse according to claim 1, wherein the shape maintaining body is composed of a coil-shaped, ring-shaped, noble-shaped or spiral-shaped metal, a high-strength resin, or a composite resin mixed with different materials. Tube catheter.

[3] The vascular catheter according to [2], wherein at least a part of the high-strength resin or composite resin is in the form of a thread.

4. The vascular catheter according to claim 2, wherein at least a part of the coil-shaped shape maintaining body is a double row coiled coil made of different materials.

[5] The vascular catheter according to any one of claims 1 and 4, wherein the shape maintaining body has a layer structure of at least two layers.

[6] The shape maintaining body is disposed on an inner surface or an outer surface of the tip portion of the chip, and is covered with a cover disposed on the inner side or the outer side of the tip portion of the chip. The vascular force tester according to any one of claims 1 to 5.

7. The vascular catheter according to any one of claims 1 to 5, wherein the shape maintaining body is disposed inside the tip.

[8] A method of manufacturing a vascular catheter including a catheter body provided with a lumen therein,

Covering the outside of the core material with a coating material having a melting point lower than that of the core material to form a coated core material,

Winding the coated core material spirally,

The coated core material is heated so that the temperature is not lower than the melting point of the coating material and lower than the melting point of the core material. A method for producing a vascular catheter, wherein the catheter body is formed in a state including the shape maintaining body as a spiral core material.

[9] A method for manufacturing a vascular catheter having a cylindrical tip having a higher flexibility than a proximal end side at the distal end portion of a catheter body having a lumen therein, the long axis of the tip In the state where the flexibility of the direction is not impaired, the melting point of the core material is higher than that of the core material for forming the shape maintaining body that maintains the opening shape of the most advanced lumen against the external force in the radial direction. A low covering material is formed to form a covering core material, and the covering core material is spirally wound,

Heating the coated core material to a temperature equal to or higher than the melting point of the coating material and lower than the melting point of the core material, and forming the chip in a state including the shape maintaining body as a spiral core material. A method for manufacturing a vascular catheter.

[10] The coated core material may be pressurized during heating by extrapolating a heat-shrinkable tube that contracts by heating to the spirally wound coated core material. Item 10. A method for producing a vascular catheter according to Item 9.