EP1890756A1

EP1890756A1 - Aspiration catheter

Info

Publication number: EP1890756A1
Application number: EP06747300A
Authority: EP
Inventors: Masaru Uchiyama; Shinichi Miyata
Original assignee: Johnson and Johnson KK
Current assignee: Johnson and Johnson KK
Priority date: 2005-06-08
Filing date: 2006-06-08
Publication date: 2008-02-27
Also published as: CN101193679A; CA2609966A1; JP2006340868A; JP4549933B2; WO2006132434A1; CN101193679B; CN102205161B; CA2609966C; EP1890756A4; CN102205161A

Abstract

An aspiration catheter system for aspirating and removing thrombi in blood vessel by inserting the catheter into the blood vessel having a catheter member and a catheter shaft wherein a tubular member of the catheter member is inserted into a tubular part of the catheter shaft, a distal end of the tubular member is projected out of a distal end of the tubular part of the catheter shaft to form an aspiration inlet of the thrombi, a proximal end of the tubular member is located in the catheter shaft, an inner space of the tubular member connects to an inner space of the catheter shaft, and thrombi is aspirated or drug solution is injected from a proximal part of the tubular part of the catheter shaft.

Description

DESCRIPTION ASPIRATION CATHETER

TECHNICAL FIELD [0001 ] The present invention relates to a catheter for blood vessel and specifically a catheter to aspirate and remove wastes such as thrombi in the blood vessel or to inject drug solution into the blood vessel.

BACKGROUND ART

[0002] Aspiration catheters conventionally have been used for removing thrombi and the like in the blood vessel. An operator inserts a catheter into a blood vessel and moves it along the blood vessel and locates the catheter at a target position to aspirate and remove the thrombi and the like. For example, the below patent document 1 discloses an aspiration catheter with dilators, having a double tubular structure comprising a central catheter and an outer catheter with almost the same diameters and same lengths, which aspirates and removes thrombi usually through the central catheter and when the central catheter is plugged up by the clots, the operator easily pulls out the central catheter from the outer catheter to exchange it for a substitute central catheter. And the outer catheter itself also functions as a catheter and can aspirate clots and the like. However the central catheter of the device of Patent Document 1 has a dilator, such a dilator decreases the effective diameter for aspiration of the catheter, also there is a flexible conical chip at the distal end of the dilator, which forms the narrowest part of the catheter and decreases the aspiration amount.

[Patent Document 1 ] Japanese Laid-Open Patent No. 24058/95

[0003] Patent Document 2 discloses a catheter device comprising a guide catheter for aspirating and removing thrombi and an evacuation sheath formed of an aspiration inlet of thrombi located inside the distal end thereof. The catheter aspirates thrombi while blocking the blood flow in the blood vessel by a balloon located outside the sheath to create a retrograde flow to prevent dispersion of debris of thrombi and to prevent blocking of the other blood vessels by the debris of thrombi. However in the combination of the guide catheter and the evacuation sheath in Patent Document 2, the space between the guide catheter and the evacuation sheath is sealed by a balloon, which makes inner diameter of the evacuation sheath to aspirate thrombi considerably narrower than the outer diameter of the guide catheter. Consequently the concept of the present invention to make the effective diameter for aspiration of the evacuation sheath as large as possible is not disclosed in the Patent Document 2.

And as the catheter of the Patent Document 2 aspirates thrombi while the balloon is dilated, it cannot move back and forth in the blood vessel during aspiration. Thereby when removing thrombi dissipated in the wide area of the blood vessel, frequent and troublesome procedures are unavoidable to repeat aspiration and movement of the catheter in blood vessels. [Patent Document 2] WO02/087677

DISCLOSURE OF THE INVENTION [Problem to be solved by the invention] [0004] As aspiration catheters in blood vessels are surgical instruments which are used by inserting into blood vessels and guided to affected parts in the blood vessels by a guide wire and the like to treat inner walls of the blood vessels or inside the blood vessels, it is necessary to make the catheters very thin, for example, usually the outer diameters thereof are less than 1 mm. Furthermore in the case of aspirating and removing high-viscosity thrombi accumulated on the inner wall of the blood vessel using a thin catheter, there raise problems such that as the aspiration pressure increases it becomes difficult or impossible to aspirate thrombi or it takes a long time even if aspiration is possible, and an excessive burden is loaded on the patient. And in the case of conventional aspiration catheters, it is inevitable that the aspiration resistance of the whole length of the catheter is loaded on the aspiration device as it is mounted along the extension line of the proximal side of the longitudinal axis of the catheter.

[0005] However as the catheters are used while inserting into blood vessels, there is a limitation of a thickness of the catheter, and it is substantially impossible to make the outer diameter thicker than conventional catheters. Consequently it is a long-felt desire that a catheter which can aspirate and remove thrombi promptly while maintaining the aspiration pressure as low as possible. Further in the case of the catheter of above Patent Document 2 which uses a balloon and by the balloon the catheter is fixed to an inner wall of a blood vessel for aspiration, it is difficult to clean up clots promptly in a wide area in the blood vessel as it is inevitable to repeat aspiration and movement of the catheter in the blood vessel. As viscous clots adhere to a wide area of walls of blood vessels, it takes a long time for the catheter of Patent Document 2 to clean up such viscous clots in a wide area, consequently frequent and busy procedures are necessary, and it is a long-felt desire to realize a catheter which can easily and promptly remove clots in a wide area and can lighten the patient's burden. [Means for solving the problem]

[0006] The present invention relates to an aspiration catheter wherein a tubular member is located at the distal side of a catheter shaft and the catheter shaft itself is used for an aspiration tube at the proximal side of the tubular part of the catheter shaft in order to secure the effective diameter for aspiration as close as the outer diameter of the catheter, setting a Y connector at the proximal end of the tubular part of the catheter shaft and aspirating from the branch conduit of the Y connector by means of the aspiration device to increase the aspiration rate by shortening the length of the aspiration conduit in which an aspiration resistance is created because of thin aspiration conduit comparing with the conventional catheter which aspirating with the aspiration device located at the extension of the proximal end of the catheter, the catheter with no balloon can smoothly aspirate thrombi of wide area in the blood vessel because the catheter can aspirate while moving the catheter in the blood vessel.

[0007] The present invention relates to a catheter member of an aspiration catheter for aspirating and removing useless wastes in blood vessel such as thrombi and/or injecting medical agent into blood vessel by inserting the catheter into blood vessel wherein the catheter device has a catheter member and a catheter shaft, the catheter member has a flexible shaft having a distal end and a proximal end and the tubular member connected to the distal end of the flexible shaft, and the proximal inner cavity of the tubular member located in the catheter shaft is connected to the cavity of the tubular part of the catheter shaft.

[0008] The catheter member of the present invention constructing a part of the catheter system comprises a flexible shaft having a distal end and a proximal end, a tubular member connected to the distal end of the flexible shaft and a hub connected to the proximal end thereof. The inner space of the proximal end of the tubular member is connected to the tubular part of the catheter shaft. The flexible shaft is a shaft that connects with the tubular member and the operating hub. There is no limitation on its sectional shape in particular, and the shape is preferably a round bar, a circular arc sectional shape extending a part of the tubular wall of the tubular member, more preferably a round bar having no orientational flexibility differences. A solid-core bar and a tubular bar can be used. In the case of the tubular bar, another surgical instrument can be inserted into the tubular member and further a blood vessel through the tubular cavities of the operational hub and the flexible shaft. [0009] The flexible shaft is connected to the proximal end of the tubular member and used to move the location of the tubular member in the tubular part of the catheter shaft. It is important that the lumen of the tubular member which aspirates thrombi connects to the inner space of the catheter shaft at the position of the catheter shaft into which the flexible shaft is inserted. There are a lot of methods for the connection. In the case of a flexible shaft having a very small outer diameter comparing with the inner space of the catheter shaft, the flexible shaft with no substantial space inside is advantageous for back-and-forth movement of the tubular member, although one can make a space therein. In this case, the inner space of the tubular member connects with mainly a space between the outside of the flexible shaft and an inside the catheter shaft. Also when the outer diameter of the flexible shaft is similar to the inner diameter of the catheter shaft, it is necessary to make a space for aspiration or injection inside the flexible shaft. In this case, it is necessary to connect the space inside the flexible shaft with the inner space of the catheter shaft by means of a slit, a cut, a hole, mesh and the like. And the inner space of the tubular member connects with the space between the outside the flexible shaft and inside the catheter shaft through the inner space of the flexible shaft. The length of the flexible shaft is normally 20 cm to 200 cm, and preferably 30 cm to 130 cm. The material of the flexible shaft can be flexible plastics or metals, and for example, polyethylene, polyurethane, nylon, nylon elastomer, ethylene-vinyl acetate copolymers, polyisoprene, polycarbonate, polystyrene, polyoxymethylene, acrylonitrile-styrene resins, m-polyphenylether, polyvinylchloride, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate and the like, and combination thereof can be used. Metal materials such as stainless steels and super-elastic metal (Ni-Ti alloy) can be preferably used. Also composite materials formed by using a metal as a core material and coating the outside of the core material with a polymer can be used.

[0010] The hub can be any shape as far as the operator can conveniently manipulate the flexible shaft, however too large or too heavy hub is inappropriate because the catheter member may get out of the clean area. When a tubular cavity is formed in the flexible shaft, the hole which connects with the cavity may be formed in the hub. And to connect with the other instruments, a medical lure taper or a medical double-start thread mechanism may be formed. As the material, polyethylene, polyurethane, nylon, nylon elastomer, ethylene-vinyl acetate copolymer, polyisoprene, polycarbonate, polystyrene, polyoxymethylene, acrylonitrile-styrene resin, m-polyphenyl ether, polyvinylchloride, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate and the like and combination thereof can be used.

[0011 ] The length of the tubular member of the catheter member can be usually

3 cm to 50 cm, and preferably 5 cm to 15 cm. The outer diameter of the tubular member is specified by the inner diameter of the catheter shaft. As the tubular member is used by inserting into the catheter shaft, it is necessary that the outer diameter of the tubular member is close enough to the inner diameter of the catheter shaft in order that blood does not leak in from the end of the aspiration catheter member or the drug solution does not leak out of the gap between the tubular member and the catheter shaft, on the other hand it is important to have a slight clearance between the tubular member and the catheter shaft so that the movement of the tubular member in the catheter shaft is not disturbed so that the operator can often move the catheter member in the back and forth directions during aspiration or injection operation. In practice, the clearance is preferably from 0.02 % to 25 %, more preferably from 0.1% to 15 % of the outer diameter of the catheter shaft used. The radial thickness of the tubular member can be from 0.02 mm to 2 mm. [0012] It is preferred that the distal end and the proximal end of the tubular member are obliquely cut so as to move smoothly during insertion of the tubular member into the connection part of the catheter shaft or blood vessel or extraction thereof. The oblique angle can be 5 ^° ~70 ^° preferably 20 ^° ~50 ^° to the lengthwise direction. The shape of cutting can be a single linear line, a composite line composed of several linear lines or a fluent arc line. The tubular member can be made by a single material or a composite material. As the single material, polyethylene, nylon, nylon elastomer, polyurethane, fluorocarbon resin, ethylene-vinyl acetate copolymer, silicone resin and the like can be used. As the composite material, two layer structure material can be used. In this case, as the inner layer, fluorocarbon resin, polyamide, polyamide elastomer, polyethylene and the like can be used, and as the outer layer, polyethylene, polyurethane, nylon, nylon elastomer, ethylene-vinyl acetate copolymer, silicone resin and the like can be used. It is possible to insert a blade (a reinforcing member in the form of a net or a spiral fiber) of metal or resin.

[0013] An X-ray-opaque marker may be made at the aspiration end of the tubular member, near the cutting parts of both the aspiration end and the opposite end to the aspiration end of the tubular member so as to prevent dropout of the tubular member from the catheter shaft by eye-observation. The marker can be formed at only one end of the two. The marker can be formed at the surface, inside or in the radial thickness of the tubular member in the shape of tube, coil, paint, powder and the like. Also it is possible to admix an X-ray-opaque material in the whole tubular member material to visualize the whole tubular member under X-ray. The materials of the marker can be any materials that is opaque to X-rays, and stainless steel, platinum, tungsten or alloy thereof and further contrast agents such as bismuth subcarbonate, bismuth oxide and barium sulfate may be used. [0014] Surface treatment may be made to attain lubricating property at the outer surface of the tubular member to reduce resistance during insertion into the catheter shaft and movement in the blood vessel. The surface treatment agent is optional and may be hydrophobic materials such as fluorocarbon resin and silicone resin or hydrophilic materials such as polyethylene glycol (PEG), polyethylene oxide (PEO), polyvinyl alcohol, polyacrylamide, and homopolymers and copolymers of methacrylic acid derivatives.

Further to enforce lubricating effect, surface treatment may be made at the inner surface of the catheter shaft as well as the surface of the tubular member.

[0015] The thrombi in the blood vessel is aspirated from the distal end of the tubular member, transferred from the proximal end of the tubular member to inner cavity of the catheter shaft, and removed through the branch conduit of Y connector by means of the aspiration device.

[0016] Although an inner lumen of the tubular member may be used as a guide wire channel, it is preferred to make an independent path for guide wire. In this case, the position of the guide wire channel can be any part against the tubular member, however whole length of the tubular member in the lengthwise direction is preferred and it is possible to form the channel only near to the aspiration end. Although the guide wire channel may be made outside the outer diameter of the tubular member, it is preferred to make the guide wire channel in the radial thickness or inside the outer diameter of the tubular member to keep the sectional shape of the tubular member round in order to prevent flow-in of the blood and flow-out of the drug solution between the catheter shaft and the tubular member. The guide wire channel may be made by the same material as the tubular member and it is possible to be integrally made with the tubular member or made independently, and also it is possible to make a part or whole part of the guide wire channel in the space in the tubular member. The inner diameter of the guide wire channel is appropriately selected according to the guide wire diameter to be used, and may be 0.1 mm to 3 mm. The guide wire channel may be made inside the flexible shaft or outside the flexible shaft independently, or it is possible not to make the guide wire channel in particular after getting out the proximal end of the tubular member. [0017] The guide wire channel can protrude out of the aspiration end of the tubular member, and the appropriate protrusion length may be 0.3 mm to 10 mm, and preferably 0.5 mm to 4 mm. The length of the guide wire channel including the protrusion length may be 5 mm to 500 mm, and preferably 10 mm to 300 mm. [0018] The sectional shape of the guide wire channel is preferably round and its inner diameter is from 0.1 mm to 3 mm and from 0.3 mm to 1 mm is particularly preferred when used for coronary arteries. The radial thickness of the guide wire channel when formed as an independent member from the tubular member may be 0.02 mm to 2 mm, preferably 0.05 mm to 0.25 mm when used for coronary arteries. The material in such case may be a single or composite material. As the single material, polyethylene, nylon, nylon elastomer, polyurethane, fluorocarbon resin, ethylene-vinyl acetate copolymer, silicone resin and the like can be used. As the composite material, two layer structure material can be used. In this case, for the inner layer of the composite material, fluorocarbon resin, polyamide, polyamide elastomer, polyethylene and the like can be used, and for the outer layer of the composite material, polyethylene, polyurethane, nylon, nylon elastomer, ethylene-vinyl acetate copolymer, silicone resin and the like can be used.

[0019] In the case of forming the end tip of the guide wire channel independent from the tubular member, a surface treatment may be made to provide lubricating property outside the end tip to reduce resistance during insertion into the catheter shaft or its movement in the blood vessel. The surface treatment agent is optional and may be hydrophobic materials such as fluorocarbon resin and silicone resin or hydrophilic materials such as polyethylene glycol (PEG), polyethylene oxide (PEO), polyvinyl alcohol, polyacrylamide, and homopolymers and copolymers of methacrylic acid derivatives.

[0020] It is preferred in view of safety to detect the position of the flexible shaft by X-ray imaging. It is possible to mix a contrast agent such as tungsten, bismuth subcarbonate, bismuth oxide and barium sulfate to the material especially in the case of resinous material. An X-ray opaque marker may be made at the tip of the protrusion part of the guide wire channel from the aspiration end in order to indicate the protrusion part. The marker can be formed on the surface, inner surface or in the radial thickness of the flexible shaft in the shape of tube, coil, paint, powder and the like. The materials of the marker can be any materials that is opaque to X-rays as set forth above.

[0021 ] Commercial products may be used as the guide wire and the thickness may be adopted according to the thickness of the blood vessel in which the catheter is inserted. The guide wires for blood vessels having thicknesses of 0.012 '\0.014'\ 0.018

'\ 0.025", 0.035" and the like are available on the market. 0.014" thickness guide wire is often used for coronary arteries of the heart. Various lengths from 30 cm to 300 cm are available on the market. The lengths from 175 cm to 190 cm or 300 cm are often used for the coronary arteries. Catheters having various structures are available and they are designed to be soft in order not to injure the blood vessels by the tip end of the guide wire. The guide wires such as those formed on the whole length of a metal coil such as stainless steel, a metal wire with a 30cm coil at the distal end which is initially inserted into blood vessel, those manufactured by composite materials such as stainless steel and super-elastic alloy (Ni-Ti alloy) and those covered with polyurethane or nylon polymers are available. The guide wire may be manipulated to guide the catheter in the blood vessel.

[0022] The catheter shaft of the present invention is a tubular shape and has an approximate uniform sectional shape and an approximate uniform sectional area. The tubular member is set in the catheter shaft as said above when the catheter shaft is used for the blood vessel catheter. The tubular member can protrude out of the distal end of the catheter shaft, however it is necessary that the proximal end of the tubular member must be always kept in the catheter shaft. Although the catheter for exclusive use may be used as the catheter shaft, commercial guiding catheters, catheters for injection of contrast agent for diagnosis and the like may be used. There are catheters of 3 Fr. to 10 Fr. in diameters and 90 cm to 120 cm in effective lengths, and there are various kinds of the distal end shape so that the catheters are stable in the blood vessels. There are products having curvatures, for example, Jadkins left, Jadkins right, Amplatz right, Amplatz left, Border, Multipurpose, Kimney, Champ, and the like.

[0023] In a structure of a catheter shaft for exclusive use, a tubular part which becomes gradually soft against bending is formed at a distal side of the catheter shaft having a distal end and a proximal end, and a connector for connecting with a connection part at the proximal end. The outer diameter of the tubular member is from 0.3 mm to 12 mm and for coronary arteries 1 mm to 3.5 mm may be used. The radial thickness can be 0.03 mm to 2 mm and for coronary arteries 0.05 mm to 0.8 mm is preferred. The tubular member can be made by a single material or a composite material. As the single material, polyethylene, nylon, nylon elastomer, polyurethane, fluorocarbon resin (FEP, PTFE, PFA, PVDF and the like), stainless steel tube, super-elastic alloy (Ni-Ti alloy) and the like and as the composite material, two layer structure material can be used. In this case, as the inner layer of the composite material, fluorocarbon resin, polyamide, polyamide elastomer, polyethylene and the like can be used, and as the outer layer of the composite material, polyethylene, polyurethane, nylon, nylon elastomer and the like can be used. It is preferred to insert metal blades (a reinforcing member in the form of a net or a spiral fiber) or resin blade between the inner layer and the outer layer to improve anti-kink property or shape-retentive property of the tube. [0024] The tubular part of the catheter shaft has an inner diameter that can contain the tubular member and also similar to an outer diameter of the tubular member. The hardness of the tubular part can be uniform on the whole or can change gradually without boundaries. It is also possible to change stepwise by more than two steps. An example of the hardness change is such that: forming a tubular part of the proximal side having a uniform hardness, and forming a tubular part of the distal side which gradually softens from the proximal side thereof toward the distal end. The length of the tubular part having changing hardness is normally no more than 35 % of the effective length of the catheter shaft which is the total lengths of the tubular part and the tubular part. Effective length of the catheter shaft is usually 70 cm to 130 cm. The tubular part can be made of a single material or a composite material. For the single material, polyethylene, nylon, nylon elastomer, polyurethane, fluorocarbon resin, ethylene- vinyl acetate copolymer, silicone resin and the like can be used. For the composite material, two layer structure material can be used. In this case, for the inner layer material, fluorocarbon resin, polyamide, polyamide elastomer, polyethylene and the like can be used, and for the outer layer material, polyethylene, polyurethane, nylon, nylon elastomer, ethylene-vinyl acetate copolymer, silicone resin and the like can be used. It is possible to insert a blade (a reinforcing member in the form of a net or a spiral fiber) of metal or resin between the inner layer and the outer layer. [0025] A connector is used for manipulating the catheter shaft itself and for connecting to a connection part, and has a space inside thereof so as to retain a diameter larger than the outer diameter of the tubular member. The outer shape can be optional while considering easiness of handling and connectability to the connection part. As the material of the connector, polycarbonate, polystyrene, polyoxymethylene, acrylonitrile-styrene copolymer, m-polyphenyl ether, polyvinylchloride, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate and the like can be adopted however a lighter-weight material is preferred so as to prevent dropout of the catheter shaft from a patient.

[0026] A surface treatment may be made to provide lubricating property on the outer surface of the catheter shaft to reduce resistance during insertion of the catheter shaft into a blood vessel. Methods of the surface treatment is optional and may be to coat the surface with hydrophobic materials such as fluorocarbon resin and silicone resin or hydrophilic materials such as polyethylene glycol (PEG), polyethylene oxide (PEO), polyvinyl alcohol, polyacrylamide, and homopolymers and copolymers of methacrylic acid derivatives.

[0027] Y connector as a connection part for connecting to the catheter shaft is used for separating the flexible shaft and the guide wire from the aspiration device and for connecting them to outside. The flexible shaft and the guide wire usually pass through the main conduit and the connection to the aspiration device is through the branch conduit although the reverse connection may be possible.

[0028] The aspiration device in the present invention is optional and not restricted in particular, and aspiration devices such as injection type and aspiration-pump type may be adopted.

EXAMPLES [0029] Fig. 1 shows an example of the present invention for catheter system 1 which is used by inserting into a blood vessel for aspirating thrombi and/or injecting drug solution into blood vessel. The figure shows whole the catheter system 1 and the figure depicts the state that the catheter member 13 is inserted into the catheter shaft 4. The catheter member 13 (not shown) comprises a tubular member 3, a flexible shaft 6, a hub 7 and a guide wire channel 10 shown in Fig. 3. The connection part between the tubular member 3 and the flexible shaft 6 is in the tubular part of the catheter shaft 4 and not shown. The connection part 5 is a Y connector in Fig. 1 and the flexible shaft 6 passes through the main conduit 11. A round bar type is used for the flexible shaft 6. A guide wire 2 also can passes through the main conduit 11 and in Fig. 1 passes through the main conduit 11 of Y connector. An aspiration device 8 is connected to the branch conduit 12. [0030] A distal end of the guide wire 2 projects out of the tubular member 3 and the guide wire channel 10, and a proximal end of the guide wire 2 protrude from Y connector. An aspiration opening 9 is at the distal end of the tubular member 3. [0031 ] An example of practical use of a catheter for aspirating thrombi of the present invention is hereafter described. First at access position to the body, a path to an artery is specified by so-called a sheath introducer by making a small hole through the skin, for example, at the wrist or the inguinal region near the root of the femoral region; the tubular part of the catheter shaft 4 containing a guide wire 2 commercially available are proceeded to near the target area through the styptic valve of the sheath introducer.

[0032] Near the target area, only the guide wire 2 is preceded to secure the route for medical treatment. After the position of the guide wire 2 and the catheter shaft 4 are roughly fixed, the guide wire 2 is passed through the guide wire channel 10 of the catheter member 13 and proceeds the catheter member 13 to approximate the area where there is targets such as thrombi between the distal end of the guide wire 2 and the distal end of the tubular part of the catheter shaft 4. The guide wire 2 precedes the catheter member 13 to prevent dropout of the guide wire 2. And a built-in styptic valve in the main conduit of the connection part 5 is slightly closed to minimize the leakage of blood. Further necessary parts such as an extension tube and a stop cock are connected to the branch conduit 12 of the connection part 5 and the aspiration device 8 is connected to the proximal end. After arrangement of the catheter system 1 has been completed, a reduced pressure is applied using the aspiration device 8 to the system 1 to aspirate thrombi, or an elevated pressure is applied to inject a drug solution after filling the necessary drug solution into the aspiration device. The catheter member 13 is moved in the blood vessels to approximate target area to aspirate thrombi or to inject the drug solution for therapy while maintaining the reduced pressure or elevated pressure.

[0033] The catheter member 13 has the flexible shaft 6 at the proximal side of the tubular member 3 having a continuous lumen between the distal end and the proximal end as shown in Fig. 1 , Fig.2 and Fig. 6, and further the hub 7 at the proximal end of the flexible shaft 6. The guide wire channel 10 for the guide wire to pass through is located at the tubular member 3 and an X-ray opaque marker is located at the distal end of the guide wire channel 10.

[0034] Although the shape of the flexible shaft 6 is optional, it is possible to make the shaft a simple solid cylindrical shape as shown in Fig. 5 or hollow cylindrical shape as shown in Fig. 7. Further it is possible that a part of the flexible shaft which is more proximal than the proximal end of the tubular member 3 inside the catheter shaft 4 may have holes or slits on the whole or a part thereof while making the outer diameter of the flexible shaft close to the inner diameter of the catheter shaft as shown in Fig. 8 to connect between the inner space of the catheter shaft 4 and that of the tubular member 3 on condition the inner space of the tubular part 4 of the catheter shaft is connected to the inner space of the tubular member 3 of the catheter member.

[0035] The connection means are optional and there are a number of forms, for example, more than one slits are formed at whole or a part of the flexible shaft 6 as in Fig. 11 , and more than one holes having various shapes instead of slits as in Fig. 13. The holes can be uniform sizes or various sizes or such holes can be mixed. Fig. 12 shows a drawing of the flexible shaft 6 where a part or whole length of the shaft is cut in the longitudinal direction. The flexible shaft 6 is not restricted to one, for example, a plurality of flexible shafts 6 are possible as shown in Fig. 9. In the case of a plurality of the flexible shafts, the shafts may be integrated at an optional position as shown in Fig. 9 or Fig. 10. In such case, it is necessary to design while considering the position of the styptic valve at the main conduit 11 of the connection part 5 so as not to leak blood therefrom. It is preferred in view of safety to detect the position of the flexible shaft by X-ray imaging. When resinous materials are used for the flexible shaft, it is preferred to mix a contrast agent such as tungsten, bismuth subcarbonate, bismuth oxide and barium sulfate considering imaging.

BRIEF DESCRIPTION OF DRAWINGS [Fig. 1 ] The aspiration catheter of the present invention. [Fig. 2] The catheter member of the aspiration catheter in Fig. 1.

[Fig. 3] The sectional drawing of A-A section of Fig. 1 . A section of the tubular member protruding out of the catheter shaft, the guide wire channel 10 is formed in the tubular wall and the guide wire is passing through therein.

[Fig. 4] B-B sectional shape of Fig. 1 . The tubular member is inserted into the catheter shaft. The part of the tubular member is the same as Fig. 3 and the guide wire channel 10 is formed in the tubular wall and the guide wire is passing through therein.

[Fig. 5] C-C sectional shape of Fig. 1 . There is no guide wire channel and guide wire is in the inner space.

[Fig. 6] The drawing of longitudinal section of the aspiration catheter system of the present invention constructing one flexible shaft.

[Fig. 7] The drawing of longitudinal section of the aspiration catheter system of the present invention constructing one flexible shaft.

[Fig. 8] The drawing of longitudinal section of the aspiration catheter system of the present invention constructing one flexible shaft. [Fig. 9] The drawing of longitudinal section of the aspiration catheter system of the present invention constructing three flexible shafts at the proximal end of the flexible shaft.

[Fig. 10] The drawing of longitudinal section of the aspiration catheter system of the present invention constructing three flexible shafts at the proximal end of the flexible shaft.

[Fig. 11 ] The drawing of longitudinal section of the aspiration catheter system of the present invention constructing one flexible shaft.

[Fig. 12] The drawing of longitudinal section of the aspiration catheter system of the present invention constructing one flexible shaft.

[Fig. 13] The drawing of longitudinal section of the aspiration catheter system of the present invention constructing one flexible shaft.

DESCRIPTION OF SYMBOLS

1 ^{• • •} catheter system, 2 ^{• • •} guide wire, 3 ^{• • •} tubular member, 4 ^{• •} • tubular part of the catheter shaft, 5 ^{• • •} connection part, 6 ^{• • •} flexible shaft, 7 ^• • ^• hub, 8 • • ^• aspiration device, 9 ^{• • •} aspiration end, 10 ^{• • •} guide wire channel, 11 ^{• • •} main conduit, 12 • • • branch conduit, 13 ^{• • •} catheter member.

Claims

1. An aspiration catheter system for aspirating and removing thrombi in blood vessel or injecting a drug solution by inserting the catheter into the blood vessel having a catheter member and a catheter shaft wherein a tubular member of the catheter member is inserted into a tubular part of the catheter shaft, a distal end of the tubular member is projected out of a distal end of the tubular part of the catheter shaft to form an aspiration inlet of the thrombi, a proximal end of the tubular member is located in the tubular part of the catheter shaft, an inner space of the tubular member connects with an inner space of the tubular part of the catheter shaft, and the thrombi is aspirated or the drug solution is injected from a proximal part of the tubular part of the catheter shaft.

2. The aspiration catheter system according to claim 1 characterized by having a connection part to an aspiration device at a proximal part of the tubular part of the catheter shaft.

3. The aspiration catheter system according to claim 2 characterized in that the connection part is a Y connector and the aspiration device or the injection device is connected to a branch conduit or a main conduit of the Y connector.

4. The aspiration catheter system according to any one of claims 1 to 3 characterized in that the catheter is capable of moving in a blood vessel while aspirating thrombi or injecting the drug solution.

5. The aspiration catheter system according to any one of claims 1 to 4 characterized in that the catheter has a guide wire and a guide wire channel to guide the guide wire.

6. The aspiration catheter system according to any one of claims 1 to 5 characterized in that the guide wire channel is formed on a tubular wall of the tubular member.

7. The aspiration catheter system according to any one of claims 1 to 6 characterized in that the guide wire is protrudable over the distal end of the tubular member.

8. The aspiration catheter system according to any one of claims 1 to 7 characterized in that a marker is formed at the distal end of the tubular member.

9. The aspiration catheter system according to any one of claims 1 to 8 characterized in that at least outer surface of each of the tubular member and the tubular part of the catheter shaft is subject to lubrication treatment.

10. A catheter member of an aspiration catheter system for aspirating and removing thrombi from a blood vessel or injecting a drug solution by inserting the catheter into blood vessel having a catheter member and a catheter shaft wherein the catheter member has a flexible shaft having a distal end and a proximal end, a hub located at the proximal end and a tubular member located at the distal end of the flexible shaft, and when the tubular member is located in the tubular part of the catheter shaft, an inner cavity of the tubular member is connected with the inner cavity of the tubular part of the catheter shaft.

11. The catheter member according to claim 10 having a guide wire channel for guiding a guide wire.

12. The catheter member according to claim 11 wherein the guide wire channel is formed on a tubular wall of the tubular member.

13. The catheter member according to any one of claims 10 to 12 characterized in that the guide wire is protrudable over the distal end of the tubular member.

14. The catheter member according to any one of claims 10 to 13 characterized in that a marker is formed at the distal end of the tubular member.

15. The catheter member according to any one of claims 10 to 14 characterized in that at least outer surface of the tubular member is subject to a lubrication treatment.