JP2009066178A - Suction catheter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a suction catheter capable of well carrying out both inserting operation into a living body and suction and removal operation of foreign matters. <P>SOLUTION: The suction catheter 10 includes an outer tube 11 and an inner tube 12. The inner tube 12 is arranged so as to be able to move in a longitudinal direction in the lumen 21 of the outer tube 11. Further, the proximal end side of the inner tube 12 is connected to a suction tool and thrombi or others are sucked and removed through the inner tube 12 by activating the suction tool. In the constitution, an elastic deforming section 32 is arranged in the distal end portion of the inner tube 12. The elastic deforming section 32 is formed so as to be able to deform to turn contracted and expanded, the elastic deforming section 32 remains contracted in the case where the inner tube 12 is in the storing position relative to the outer tube 11, and the elastic deforming section 32 remains expanded in the case where the inner case 12 is in the protruded position. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an aspiration catheter for aspirating and removing a foreign substance such as a thrombus in a blood vessel.

As a suction catheter, for example, a thrombus suction catheter is known (see, for example, Patent Document 1). A thrombus aspiration catheter is used for aspirating and removing a thrombus present in a blood vessel such as a coronary artery. Specifically, the treatment person inserts a thrombus aspiration catheter into a blood vessel and moves the inside of the blood vessel to reach a treatment target site where a thrombus exists. Then, the thrombus is aspirated and removed by applying a negative pressure to the inside of the catheter using a suction tool attached to the proximal end of the thrombus aspiration catheter.
JP 2004-222946 A

  Here, the suction catheter is inserted into the living body as described above and is used by moving to the treatment target site, and it is necessary to reduce the diameter in order to improve the insertion operation. is there. In particular, since a thrombus aspiration catheter may be used by being inserted into a relatively thin blood vessel, it is highly necessary to reduce the diameter accordingly.

  However, if the diameter of the suction catheter is reduced, the suction port of the suction catheter becomes smaller and the suction and removal of foreign matter cannot be performed well. For example, if the suction port is small in the thrombus suction catheter, it is necessary to perform suction many times in order to suck the thrombus, and the suction operation takes a long time.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a suction catheter capable of satisfactorily performing both insertion into a living body and suction and removal of foreign matter. .

  Hereinafter, means and the like effective for solving the above-described problems will be described while showing functions and effects as necessary. In the following, in order to facilitate understanding, a corresponding configuration example in the embodiment of the invention is appropriately shown in parentheses, etc., but is not limited to the specific configuration shown in parentheses.

  The suction catheter (suction catheter 10) of the present invention includes a suction tube (inner tube 12) in which a suction lumen is formed, and the suction tube has a contracted state and an expansion at its distal end. When the deformable portion is in the expanded state, the lumen suction port (suction port 43) is a region closer to the proximal side. When the deformed portion is in the contracted state, the outer peripheral surface of the suction tube is contracted in the distal end portion more than in the expanded state.

  According to this configuration, when the foreign substance is sucked and removed, the suction port of the lumen of the suction tube is expanded compared to the region on the proximal side by setting the deformed portion in the expanded state. As a result, even when the suction catheter is thinly formed so that the insertion into the living body can be performed satisfactorily, the suction port can be expanded when the foreign matter is sucked and removed. It becomes easy to get in. Therefore, it is possible to satisfactorily remove foreign matter by suction. On the other hand, the deformable portion can be deformed into a contracted state, and by bringing the deformable portion into the contracted state, the outer peripheral surface of the suction tube is contracted at the distal end portion more than the expanded state. Therefore, it is possible to make the suction catheter thinner during the insertion operation into the living body, and the workability of the insertion operation is not reduced by the deforming portion. As described above, according to this configuration, it is possible to satisfy both conflicting demands of improving workability for insertion into a living body and improving suction and removal of foreign matters.

  It is preferable that the deformable portion is formed to be elastically deformable and is urged toward the expanded state by its own urging force in the contracted state. According to this structure, the deformation | transformation between a contracted state and an expanded state of a deformation | transformation part is performed based on self biasing force. Thereby, it becomes possible to make a deformation | transformation part into a comparatively simple structure, and it becomes possible to acquire the said outstanding effect by this comparatively simple structure. In particular, the distal end portion of the suction catheter is a part to be inserted into the living body, and it is preferable that the part to be inserted into the living body has a simple configuration.

  Further, in the configuration in which the suction tube is inserted into the living body with the outer peripheral surface covered with the guide tube and is movable in the longitudinal direction within the lumen of the guide tube, the deformation In a state in which the suction tube is arranged so that the portion is located in the lumen of the guide tube, the outer peripheral surface (outer peripheral surface 45) of the deformable portion hits the inner peripheral surface of the guide tube. In the state where the suction tube is disposed such that the portion is elastically deformed and is in the contracted state, and the deformed portion is located at a position protruding distally from the distal end side opening of the guide tube, It is preferable that the deforming portion is in the expanded state by the self urging force.

  With this configuration, deformation between the contracted state and the expanded state of the deforming portion is performed through the lumen of the guide tube, and the influence on the living body due to the deformation is reduced. In addition, it is possible for the treatment person to change the deformed portion between the contracted state and the expanded state only by changing the relative position in the longitudinal direction of the suction tube with respect to the guide tube, which improves the workability. Figured.

  Or it replaces with the structure using said guide tube, and it is good also as the following structures. That is, an outer tube (outer tube 11) surrounding the outer side of the suction tube is further provided, the suction tube is provided so as to be movable in the longitudinal direction within the lumen (lumen 21) of the outer tube, and the deforming portion is expanded. In the state, the maximum outer diameter is larger than the inner diameter of the lumen of the outer tube, and in the state where the suction tube is arranged so that the deforming portion is located in the lumen of the outer tube, the deforming portion The outer peripheral surface (outer peripheral surface 45) of the outer tube contacts the inner peripheral surface of the outer tube, so that the deformed portion is elastically deformed and is in the contracted state, and the deformed portion is distant from the distal end side opening of the outer tube. In the state where the suction tube is disposed so as to protrude to the position, the deforming portion is in the expanded state by the self biasing force. It is preferable to.

  By adopting this configuration, deformation between the contracted state and the expanded state of the deformed portion is performed via the lumen of the outer tube, and the influence on the living body due to the deformation is reduced. In addition, it is possible for the treatment person to change the deformed portion between the contracted state and the expanded state only by changing the relative position in the longitudinal direction of the suction tube with respect to the outer tube, which improves the workability. It is done. Furthermore, in this configuration, the outer diameter of the portion into which the suction catheter is inserted is defined by the outer tube in the insertion operation of the suction catheter into the living body, and the suction larger than the inner diameter of the outer tube in the suction removal operation. It is possible to suck and remove foreign matter through the mouth.

  In the configuration using the guide tube or the outer tube as described above, it is preferable that the deforming portion is formed so that the outer peripheral surface in the expanded state is widened toward the suction port. As a result, the suction tube is moved from the position where the deformed portion protrudes more distally than the distal end opening of the guide tube or outer tube to the position where the deformed portion enters the lumen of the guide tube or outer tube. When moved, the deformed portion in the expanded state is deformed into a contracted state by its outer peripheral surface hitting the periphery of the opening on the distal end side and gradually contracting along the tapered outer peripheral surface. Become. Therefore, the deforming portion can be favorably deformed from the expanded state to the contracted state.

  Preferably, the deformed portion is formed of a superelastic alloy. Thereby, while being able to form a deformation | transformation part so that elastic deformation is possible, it can form so that it may be urged | biased to the said expansion state side with an own urging | biasing force. Moreover, it becomes possible to give a contrast function to a deformation | transformation part by forming a deformation | transformation part with a superelastic alloy. That is, it becomes possible to make the deformed portion multifunctional. By providing the deforming portion with a contrast function, the position of the deforming portion can be confirmed from outside the body under X-ray projection, and the suction tube can be inserted favorably.

  When the suction catheter is used for sucking a thrombus in a blood vessel, the deformed portion has an outer peripheral surface in at least a partial region in the longitudinal direction in the expanded state. It is preferable to form so that it may closely contact. Accordingly, the size of the suction port can be expanded to the inner diameter of the blood vessel to be thrombus sucked during the thrombus suction operation. Therefore, the thrombus can easily enter the aspiration catheter, and the thrombus can be satisfactorily removed by suction.

  It is preferable that the deformation portion has a hole (through hole portion 42) penetrating in the thickness direction of the deformation portion. Alternatively, the use of the suction catheter is for sucking a thrombus in a blood vessel, and the deforming portion is formed to be elastically deformable, and in the contracted state, it is biased toward the expanded state by its own biasing force. In the case where it is formed in such a manner, a hole for preventing the blood flow from being blocked in the expanded state is formed in the wall portion constituting a part of the lumen of the suction tube in the deformable portion. It is good also as the structure which carried out. According to the above configuration, even if the deformed portion is in an expanded state in order to perform suction removal of the thrombus, blood can pass through the hole portion, and the above excellent effect can be achieved while suppressing the influence on the blood flow as much as possible. Obtainable. In particular, in the configuration in which the outer peripheral surface in at least a part of the longitudinal direction is in close contact with the inner peripheral surface of the blood vessel to be thrombus-aspirated when the deformed portion is in the expanded state, a hole is formed in the deformable portion. Therefore, it is possible to prevent blood flow from being blocked when the deformed portion is in the expanded state.

  Further, the deformed portion may be formed in a mesh shape so as to form the hole portion. In this case, it is possible to obtain the above-described excellent effect due to the configuration having the hole while suppressing a part of the thrombus from passing through the hole.

  When the deforming portion is in the expanded state, it is preferable to form the deforming portion so that the lumen of the suction tube is divergent toward the suction port at the distal end portion. As a result, when the foreign substance is sucked and removed with the deformed portion in the expanded state, the foreign substance that has entered from the suction port is suppressed from being caught on the inner peripheral surface of the lumen of the suction tube, and the suction and removal of the foreign substance is excellent. Can be performed.

  Hereinafter, an embodiment in which the present invention is embodied in a thrombus aspiration catheter will be described with reference to the drawings. FIG. 1 is a schematic overall side view of a suction catheter 10, and FIGS. 2 and 3 are explanatory views for explaining the configuration of a region C in FIG. In the following description, the end on the region C side in the suction catheter 10 will be referred to as a distal end (tip), and the end opposite to the region C will be described as a proximal end (base end). .

  As shown in FIG. 1, the suction catheter 10 has an inner and outer double tube structure including an outer tube 11 and an inner tube 12. The suction catheter 10 includes an outer tube hub 13 attached to the proximal end portion of the outer tube 11 and an inner tube hub 14 attached to the proximal end portion of the inner tube 12. ing.

  The outer tube 11 is formed of a material having flexibility and sufficient rigidity to be inserted into a living body. Specifically, it is made of polyamide. However, it is not limited to polyamide, and may be formed of polyethylene, polyethylene terephthalate, polypropylene, polyurethane, polyamide elastomer, polyimide, polyimide elastomer, silicon rubber, natural rubber, or the like. Further, these materials or other materials may be blended or copolymerized. Moreover, you may form with metal materials, such as stainless steel, titanium, and a Ni-Ti alloy. Further, the entire outer tube 11 does not need to be formed of a synthetic resin material, and the outer tube 11 is formed by connecting a plurality of tube bodies formed of different materials in the longitudinal direction (axial direction). Also good.

  As shown in FIG. 2, the outer tube 11 has one lumen 21 therein. The lumen 21 extends in the longitudinal direction of the outer tube 11 and is opened on each of the proximal end surface and the distal end surface of the outer tube 11. The outer diameter and the inner diameter of the outer tube 11 are the same throughout the longitudinal direction, but at least one of the outer diameter and the inner diameter may be changed at an intermediate position in the longitudinal direction. Further, the length dimension and diameter of the outer tube 11 may be appropriately determined according to the use of the suction catheter 10.

  An outer tube hub 13 is attached to the proximal end portion of the outer tube 11 as shown in FIG. The outer tube hub 13 includes a through hole 22 opened at each of the proximal end and the distal end, and the through hole 22 communicates with the lumen 21 of the outer tube 11. The shape, size, and forming material of the outer tube hub 13 are arbitrary.

  The inner tube 12 is inserted into the lumen 21 of the outer tube 11 from the outer tube hub 13 side, and the inner tube 12 is movable in the longitudinal direction of the outer tube 11 in the lumen 21. Further, the length of the inner tube 12 is larger than the combined length of the outer tube 11 and the outer tube hub 13, and the proximal end of the inner tube 12 is at the outer tube hub 13 as shown in FIG. It is located on the proximal end side of the catheter 10 for suction.

  As shown in FIG. 2, the inner tube 12 includes a tube portion 31 and an elastic deformation portion 32 that is attached to the distal end portion of the tube portion 31 and constitutes the distal end portion of the inner tube 12. . The tube part 31 is formed of a material that has flexibility and can obtain sufficient rigidity for insertion into a living body. Specifically, like the outer tube 11, it is made of polyamide. However, it is not limited to polyamide, and may be formed of polyethylene, polyethylene terephthalate, polypropylene, polyurethane, polyamide elastomer, polyimide, polyimide elastomer, silicon rubber, natural rubber, or the like. Further, these materials or other materials may be blended or copolymerized. Moreover, you may form with metal materials, such as stainless steel, titanium, and a Ni-Ti alloy. Further, the entire tube portion 31 does not need to be formed of a synthetic resin material, and the tube portion 31 is formed by connecting a plurality of tube bodies formed of different materials in the longitudinal direction (axial direction). Also good. Further, the outer tube 11 may be formed of a different material.

  The tube portion 31 has one lumen 34 therein. The lumen 34 extends in the longitudinal direction of the tube portion 31, and is open on each of the proximal end surface and the distal end surface of the tube portion 31. In addition, although the outer diameter and inner diameter of the tube part 31 are the same over the whole longitudinal direction, you may change at least one of an outer diameter or an internal diameter in the middle position of a longitudinal direction.

  As shown in FIG. 1, the inner tube hub 14 is attached to the proximal end portion of the tube portion 31. The inner tube hub 14 includes a through hole 35 opened at each of the proximal end portion and the distal end portion, and the through hole 35 communicates with the lumen 34 of the tube portion 31. The inner tube hub 14 is connected to an aspirator (not shown) through an intervening tube 36. By operating the aspirator, thrombus and the like are aspirated through the inner tube 12. The inner tube hub 14 is formed with a guide wire port portion 37. The shape, size, and forming material of the inner tube hub 14 are arbitrary.

  The elastic deformation portion 32 is attached to the distal end portion of the tube portion 31 as described above. The elastic deformation portion 32 is formed to be deformable into a natural state as an expanded state and a contracted state contracted from the natural state. The elastic deformation part 32 will be described in detail.

  The elastic deformable portion 32 is formed of an elastic material so that it is naturally held in its natural state by its own biasing force in a natural state where no external force is applied. Specifically, it is formed of a Ni—Ti alloy. However, you may form with other superelastic alloys, such as Au-Cd alloy, Cu-Al-Ni alloy, Ni-Ti-Co alloy, or Ni-Ti-Cu alloy. These superelastic alloys have X-ray contrast properties.

  2 and 3, the elastic deformation portion 32 is formed in an annular shape, and the wall portion 41 is formed in a mesh shape (mesh shape) having a large number of through-hole portions 42 penetrating inside and outside. The large number of through-hole portions 42 constituting the mesh shape are formed in a size that allows passage of bodily fluids such as blood while preventing passage of foreign matters such as thrombus. Incidentally, the mesh-like wall portion 41 is formed by knitting or weaving a Ni—Ti alloy wire, and the thickness of the wall portion 41 is smaller than the thickness of the tube portion 31 or the outer tube 11. ing. In addition, it is good also as a mesh shape by arranging many through-hole parts in parallel with respect to a face material.

  The elastic deformation portion 32 is attached to the tube portion 31 so that the inner hole thereof is located on the same axis as the lumen 34 of the tube portion 31 and communicates with the lumen 34. That is, the inner hole of the elastic deformation portion 32 constitutes a lumen of the inner tube 12 at the distal end portion of the inner tube 12. Here, since the inner tube 12 has a function of sucking a thrombus or the like as described above, it can be said that the elastic deformation portion 32 constitutes a suction port of the inner tube 12.

  In addition, the structure regarding attachment of the elastic deformation part 32 to the tube part 31 is arbitrary, for example, as a structure which embeds the proximal end part of the elastic deformation part 32 in the wall part of the tube part 31 at the time of resin molding of the tube part 31 Alternatively, it may be configured to adhere using an adhesive or the like.

  As described above, the elastically deforming portion 32 is urged toward the natural state by its own urging force. In the natural state, both the inner and outer diameters are open on the distal end side (see FIG. 3). It is formed in a megaphone shape so that its diameter gradually increases toward the suction port 43. That is, the elastically deformable portion 32 is formed so as to have a tapered shape in which both the inner peripheral surface 44 and the outer peripheral surface 45 are gradually enlarged toward the opening 43 on the distal end side at least in a natural state. Furthermore, the elastically deformable portion 32 is formed so that both the inner peripheral surface 44 and the outer peripheral surface 45 expand toward the distal end side opening 43 at least in a natural state. Since the elastic deformation portion 32 is formed in this manner, the lumen of the inner tube 12 has a shape in which the diameter of the lumen of the inner tube 12 is expanded toward the suction port at the distal end portion in a state where the elastic deformation portion 32 is in a natural state. Become.

  When the elastic deformation portion 32 is in a natural state, the outer diameter of the end portion on the opening 43 side in the elastic deformation portion 32, that is, the maximum outer diameter L1 of the elastic deformation portion 32 is larger than the outer diameter L2 at the distal end portion of the outer tube 11. (L1> L2). That is, when the elastically deformable portion 32 is in a natural state, the suction port 43 of the inner tube 12 has a larger diameter than the opening on the distal end side of the lumen 21 of the outer tube 11, and further, the diameter of the suction port 43 is It is larger than the outer diameter L2 at the distal end portion of the outer tube 11. Incidentally, when the main suction catheter 10 is used for blood vessel thrombus suction, the maximum outer diameter L1 in the natural state of the elastic deformation portion 32 is set larger than the inner diameter of the target blood vessel in which the main suction catheter 10 is used. It is preferable.

  As described above, the inner tube 12 is movable in the longitudinal direction of the outer tube 11 within the lumen 21 of the outer tube 11. As a result, the inner tube 12 has a housing position in which the elastic deformation portion 32 has entered the lumen 21 of the outer tube 11 as shown in FIG. 2, and the entire elastic deformation portion 32 has a lumen of the outer tube 11 as shown in FIG. It is possible to move to a projecting position projecting more distally than 21.

  When the inner tube 12 is in the storage position, as shown in FIG. 2, the maximum outer diameter L1 in the natural state of the elastically deformable portion 32 is larger than the outer diameter L2 of the outer tube 11 as described above. When the external force is applied from the outer tube 11 to the elastic deformation portion 32 and the elastic deformation portion 32 is elastically deformed, the elastic deformation portion 32 is contracted more than the natural state. In this contracted state, the elastically deforming portion 32 is biased so as to return to its natural state by its own biasing force, whereby at least the distal end side of the elastically deforming portion 32 has a substantially entire circumference of the outer tube 11. It is in close contact with the inner peripheral surface of the lumen 21. Further, as described above, the lumen of the inner tube 12 is not blocked in the elastic deformation portion 32 by being biased so as to return to the natural state by the self-urging force. When the suction catheter 10 is inserted into the body, a guide wire is used. However, since the lumen of the inner tube 12 is not blocked in the elastic deformation portion 32 as described above, the suction catheter 10 using the guide wire is used. It becomes possible to perform a guide.

  When the inner tube 12 is moved to the protruding position, as shown in FIG. 3, the entire elastic deformation portion 32 protrudes more distally than the lumen 21 of the outer tube 11. 32 returns to its natural state by its own urging force. As a result, the lumen of the inner tube 12 is expanded at the distal end. When the inner tube 12 is moved again to the accommodation position, the elastically deformable portion 32 enters the lumen 21 of the outer tube 11 and contracts as shown in FIG.

  A method of using the suction catheter 10 having the above configuration will be described with reference to FIG.

  First, a guiding catheter is inserted through a sheath introducer inserted into a blood vessel. Next, the guide wire is inserted into the lumen of the inner tube 12 through the port portion 37 of the inner tube hub 14 and is inserted into the guiding catheter to a position beyond the treatment target site where the thrombus 51 exists. Subsequently, the suction catheter 10 is inserted along the guide wire to the treatment target site while performing a push-pull or twist operation. As a result, as shown in FIG. 4A, the distal end portion of the suction catheter 10 is positioned in front of the thrombus 51.

  Here, the inner tube 12 is disposed at the storage position during the insertion operation. Thereby, the outer peripheral surface of the part inserted into the blood vessel in the suction catheter 10 is constituted only by the outer peripheral surface of the outer tube 11. Since the outer diameter of the outer tube 11 is set in accordance with the inner diameter of the blood vessel to be treated and the guiding catheter to be used, the aspiration catheter 10 can be inserted satisfactorily.

  The elastically deformable portion 32 is made of a Ni—Ti alloy as described above, and the Ni—Ti alloy has X-ray contrast properties. Thereby, when inserting the suction catheter 10 into a treatment object location, the position of the distal end portion of the suction catheter 10 in the living body can be confirmed from outside the body under fluoroscopy. During the insertion operation, the position of the elastically deforming portion 32 is confirmed from outside the body, so that the elastically deforming portion 32 reaches a good position for the suction and removal of the thrombus 51 when the inner tube 12 is set to the protruding position. Thus, the insertion position of the suction catheter 10 can be adjusted.

  After the suction catheter 10 is inserted to the treatment target site, the inner tube 12 is pushed to the distal side by holding the inner tube hub 14 to bring the inner tube 12 into the protruding position as shown in FIG. Deploy. And by arrange | positioning the inner tube 12 in a protrusion position, the elastic deformation part 32 is expanded so that it may return to a natural state (expanded state) with an own urging | biasing force, and the lumen | rumen of the inner tube 12 is expanded in a suction port. The In this case, since the elastic deformable portion 32 is selected such that the outer diameter (maximum outer diameter) of the distal end portion is larger than the inner diameter of the blood vessel 52 to be treated in the natural state, at least the elastic deformable portion 32 in the elastic deformable portion 32 is selected. The entire peripheral edge of the distal end portion is in close contact with the inner peripheral surface of the blood vessel 52.

  By operating the suction device connected to the proximal end portion of the inner tube 12 via the inner tube hub 14 in the above state, the inside of the lumen of the inner tube 12 becomes negative pressure, and the thrombus 51 is removed by suction. . In this case, as described above, the elastic deformation portion 32 expands the lumen of the inner tube 12 at the suction port, so that the suction efficiency is increased. As shown in FIG. The thrombus 51 and the like existing in a state of being opposed to each other on the peripheral surface can be efficiently removed by suction. That is, assuming a configuration in which the lumen suction port of the inner tube 12 is not expanded, for example, in the case of FIG. 4B, the suction port is brought close to one of the upper or lower thrombus 51 and the thrombus 51 is moved. After the suction and removal, it is necessary to bring the suction port to the other thrombus 51 and remove the thrombus 51 by suction. In this case, it is necessary to suck and remove each of the thrombus 51 individually, which may increase the work time. Further, the operation of bringing the suction port toward one wall side in the blood vessel 52 is not easy. On the other hand, according to the present suction catheter 10, the thrombus 51 can be efficiently suctioned and removed as described above.

  In addition, since the entire circumference of the distal end of the elastically deformable portion 32 is in close contact with the inner peripheral surface of the blood vessel 52, the thrombus 51 flows between the outer tube 11 and the blood vessel 52 beyond the suction port. Can be prevented. This can prevent the thrombus 51 from flowing to other parts. For example, when the thrombus 51 exists in the left main coronary artery trunk, the thrombus 51 can be prevented from flowing into the cerebral blood vessel through the aortic arch and carotid artery beyond the suction port, and the thrombus 51 exists in the femoral artery In this case, it is possible to prevent the blood clot 51 from flowing away.

  Further, in a state where the elastic deformation portion 32 is expanded, the lumen of the inner tube 12 has a tapered shape continuously expanded toward the suction port. Thereby, it is suppressed that the thrombus that has entered from the suction port is caught on the inner peripheral surface 44 of the elastically deforming portion 32, and the thrombus can be satisfactorily removed by suction.

  Further, as described above, the elastic deformation portion 32 is formed in a mesh shape, so that at least the entire periphery of the distal end portion of the elastic deformation portion 32 is in close contact with the inner peripheral surface of the blood vessel 52 as described above. In the configuration, the blood flow is not blocked even during the suction removal operation of the thrombus 51. Therefore, the above-described excellent effect can be obtained while reducing the burden on the living body. In this case, the elastically deforming portion 32 is formed in a mesh shape, and the opening area of each through-hole portion 42 is such that the thrombus 51 cannot pass therethrough. Is possible.

  After the operation of removing the thrombus 51 by suction, the inner tube 12 is placed in the accommodation position by holding the inner tube hub 14 and pulling the inner tube 12 proximally. In this case, as shown in FIG. 4C, the elastically deformable portion 32 is deformed from the natural state to the contracted state by hitting the periphery of the distal end side opening of the outer tube 11, but elastically deformed as described above. Since the outer peripheral surface 45 of the portion 32 has a tapered shape in which the diameter is gradually increased toward the opening 43 on the distal end side, the deformation to the contracted state is guided by itself and the deformation is favorably performed.

  After the inner tube 12 is placed in the storage position, the suction catheter 10 is extracted from the body. In this case, since the inner tube 12 is disposed at the accommodation position, the outer peripheral surface of the portion of the suction catheter 10 inserted into the blood vessel is constituted only by the outer peripheral surface of the outer tube 11, and the suction catheter 10 Can be satisfactorily performed.

  The suction catheter 10 is mainly passed through the blood vessel as described above and used for treating blood vessels such as coronary arteries, femoral arteries, and pulmonary arteries. It can also be applied to “tubes” in the body and “body cavities”.

  As described above in detail, in the present embodiment, the elastically deformable portion 32 that can be deformed into a contracted state and an expanded state (natural state) is provided at the distal end portion of the inner tube 12, and the inner tube 12 is attached to the outer tube 11. On the other hand, when the housing position is set, the elastic deformation portion 32 is in a contracted state, and the outer peripheral surface of the suction catheter 10 is defined by the outer tube 11. The deformable portion 32 is in the expanded state, and the suction port 43 of the inner tube 12 is expanded. Thereby, the suction port 43 can be expanded by disposing the inner tube 12 at the protruding position at the time of sucking and removing the thrombus, and the thrombus easily enters the suction catheter 10. Therefore, the suction and removal of the thrombus can be performed satisfactorily. On the other hand, when performing an insertion operation or extraction operation into a blood vessel, the outer tube 11 defines the outer diameter of the portion inserted into the living body in the suction catheter 10 by arranging the inner tube 12 in the accommodation position. Thus, the suction catheter 10 can be reduced in diameter. Therefore, the workability of the insertion operation and the extraction operation is not reduced by the elastic deformation portion 32. From the above, it is possible to satisfy both conflicting demands of improving the workability of insertion into the living body and the workability of extracting and improving the ability to suck and remove the thrombus.

  Further, since the elastic deformation portion 32 is formed of a Ni—Ti alloy, the elastic deformation portion 32 can be elastically deformed and is urged toward the expanded state by its own urging force. As a result, the elastic deformation portion 32 can have a relatively simple configuration, and the above-described excellent effect can be obtained with this relatively simple configuration. In particular, the distal end portion of the suction catheter 10 is a part to be inserted into the living body, and it is preferable that the part to be inserted into the living body has a simple configuration. In addition, since the elastic deformation portion 32 is formed in a mesh shape with the Ni—Ti alloy, the elastic deformation between the contracted state and the expanded state is favorably performed while ensuring the strength of the elastic deformable portion 32.

  Further, as described above, when the inner tube 12 is in the housing position with respect to the outer tube 11, the elastic deformation portion 32 is in a contracted state, and when the inner tube 12 is in the protruding position with respect to the outer tube 11, elastic deformation is performed. The part 32 is in an expanded state. Thereby, the deformation | transformation between the contracted state and the expanded state of the elastic deformation part 32 is performed via the lumen | rumen 21 of the outer side tube 11, and the influence on the biological body by performing the said deformation | transformation is reduced. In addition, it becomes possible for the treatment person to deform the elastic deformation portion 32 between the contracted state and the expanded state only by changing the relative position in the longitudinal direction of the inner tube 12 with respect to the outer tube 11. Improvement is achieved.

  The present invention is not limited to the description of the above embodiment, and may be implemented as follows, for example.

  (1) A modification of the suction catheter is shown in FIG. FIG. 5A is an explanatory diagram for explaining the suction catheter 60 when the deforming portion is in the contracted state, and FIG. 5B is a diagram for explaining the suction catheter 60 when the deforming portion is in the expanded state. It is explanatory drawing of.

  The suction catheter 60 has an inner / outer double tube structure including an outer tube 61 and an inner tube 62 as in the suction catheter 10 in the above embodiment. The inner tube 62 is inserted in the lumen 63 of the outer tube 61 so as to be movable in the longitudinal direction of the outer tube 61.

  A balloon 64, which is a cylindrical elastic body, is fixed to the distal ends of the outer tube 61 and the inner tube 62 so that the inside of the cylinder is airtight or liquid tight. The balloon 64 is made of a material similar to that of a general balloon catheter such as polyamide elastomer. In the present suction catheter 60, the inner tube 62 and the balloon 64 constitute a suction tube. Deformation between the contracted state and the expanded state of the balloon 64 constituting the suction tube will be described below.

  As shown in FIG. 5A, in a situation where the inner tube 62 is disposed at a position where the distal end side opening 65 of the inner tube 62 enters the lumen 63 of the outer tube 61, most of the balloon 64 is also disposed. The outer tube 61 enters the lumen 63. In this case, the balloon 64 does not block the lumen of the suction tube, and the guide wire path is secured.

  5B, in the situation where the inner tube 62 is disposed at a position where the distal end opening 65 of the inner tube 62 coincides with the distal end opening 67 of the outer tube 61, the outer tube When the fluid is supplied into the balloon 64 through the lumen 63 of the tube 61, the balloon 64 is inflated. In this case, the balloon 64 is formed so as to expand in a direction in which the suction port of the lumen of the suction tube is expanded, and the distal end of the inner peripheral surface of the outer tube 61 is a distal end opening. It is tapered so that its diameter increases toward 67. Therefore, the balloon 64 is inflated in the direction of expanding the suction port of the lumen of the suction tube. The balloon 64 is selected such that the outer diameter of its distal end is larger than the inner diameter of the blood vessel 69 to be treated in the expanded state, so that at least the entire peripheral edge of the balloon 64 has a peripheral edge around the blood vessel. It becomes close to the inner peripheral surface of 69.

  As described above, according to the present configuration, the configuration of the deformable portion and the periphery of the deformable portion is more complicated than that of the above embodiment, and further, it is necessary to supply a fluid through the outer tube 61, but as in the above embodiment. The distal end portion of the suction tube can be expanded or contracted as necessary, and the insertion operation of the suction catheter 60 into the treatment target portion is improved, and the suction and removal operation of the thrombus is improved. It can be.

  (2) In the suction catheter 10 in the above embodiment, the configuration of the outer tube 11 and the configuration of the elastic deformation portion 32 may be changed as shown in FIG. Each of these changes will be described below.

  First, the change regarding the outer tube 11 will be described. A tapered surface 72 is formed at the distal end portion of the inner peripheral surface of the outer tube 11 so as to be tapered toward the distal end side opening 71. In more detail, the taper surface 72 is a curved taper so as to have a curved surface convex inward. Thereby, when the inner tube 12 moves from the projecting position to the housing position, the mesh-like elastic deformable portion 32 is elastic without causing a problem that it is caught at the periphery of the distal end side opening 71 of the outer tube 11. It is possible to favorably deform the deformable portion 32 into the contracted state. In addition, it is not essential that the taper surface 72 has a curved surface shape, and the taper surface 72 may be formed to have a vertical cross-sectional shape.

  Next, the change regarding the elastic deformation part 32 is demonstrated. The elastically deformable portion 32 has a distal end portion 73 bent inward, and the bent portion 74 has a curved surface. That is, the elastically deformable portion 32 has a distal end portion 73 formed in a curved surface shape. Thereby, the elastic deformation part 32 will be in an expanded state, and when the distal end part 73 of the elastic deformation part 32 hits the inner peripheral surface of an object blood vessel, the contact part can be made into a smooth shape. In addition, while extending the distal end part 73 in the said structure to the proximal end side, you may embed the extended end part in the tube part 31. FIG.

  (3) In the suction catheter 10 in the above embodiment, the configuration of the elastically deformable portion may be changed as shown in FIG. The changes will be described below.

  In the above embodiment, the elastic deformation portion 32 has a shape in which the outer peripheral surface 45 extends linearly from the proximal end portion to the entire distal end portion in the natural state. The gradient (relative to the longitudinal direction) from the proximal end portion to the distal end portion of the outer peripheral surface 82 changes at a midway position in the longitudinal direction, and the distal end side is more than the proximal end side. It has a gentle slope. That is, the outer peripheral surface 82 is diverging from the proximal end portion toward the distal end portion, and has a shape bulging outward. Furthermore, the elastic deformation part 81 has a bell shape. According to this configuration, the contact area between the outer peripheral surface 82 of the elastic deformation portion 81 and the inner peripheral surface of the blood vessel can be ensured wider than that in the above embodiment, and the adhesion to the blood vessel can be improved. Moreover, it is prevented that the elastic deformation part 81 turns over to the proximal end side, and accordingly, deformation of the suction port can be prevented.

  (4) In the above embodiment, the elastic deformation portion 32 is formed in a mesh shape so that the elastic deformation portion 32 has a hole. Instead, a plurality of slits are provided in the elastic deformation portion 32. It is good also as a structure which the said elastic deformation part 32 has a hole by forming. Even if it is the said structure, the effect of reducing the influence on the blood flow in the case of carrying out the suction removal of the thrombus by expanding the suction port by the elastic deformation part 32 is acquired.

  (5) In the above-described embodiment, at least the distal end portion on the inner peripheral surface of the outer tube 11 may be subjected to a friction reduction process. Specifically, a hydrophilic polymer (maleic anhydride copolymer) or a fluorine resin (for example, polytetrafluoroethylene) may be coated. Further, instead of the low friction treatment, at least the distal end portion of the outer tube 11 may be formed of a material having low friction. Specifically, it may be formed of silicon rubber or fluorine resin. According to these configurations, when the inner tube 12 is moved between the protruding position and the housing position, the slipperiness of the elastic deformation portion 32 with respect to the inner peripheral surface of the outer tube 11 can be improved.

  Moreover, you may make it perform the above low friction processes on the outer peripheral surface of the elastic deformation part 32. FIG. In this case, when the inner tube 12 is moved between the protruding position and the housing position, not only can the slipperiness of the elastic deformation portion 32 with respect to the inner peripheral surface of the outer tube 11 be improved, but also the inner peripheral surface of the target blood vessel The slipperiness of the elastically deformable portion 32 with respect to can also be improved.

  (6) Instead of the elastic deformation portion 32 formed of a superelastic alloy, the elastic deformation portion 32 is formed of a thermoplastic elastomer such as a styrene elastomer, a polyamide elastomer, a polyester elastomer, a polyolefin elastomer, a polyurethane elastomer, or a PVC elastomer. Alternatively, it may be formed of a rubber-based resin such as silicon rubber or natural rubber. Even with this configuration, the elastic deformation portion 32 can be deformed between the contracted state and the expanded state based on its urging force.

  (7) The elastic deformation portion 32 has a configuration in which both the inner periphery and the outer periphery are circular, but is not limited thereto, and at least one of the inner periphery or the outer periphery is an ellipse or a polygon. Also good.

  (8) Instead of the outer tube 11 having one lumen, a tube having a plurality of lumens may be used. In this case, one of the plurality of lumens may be used for the inner tube 12 and the other one may be used for the guide wire. Further, one of the plurality of lumens may be used for the inner tube 12 and the other one may be used for an imaging apparatus for imaging the inner peripheral surface of the blood vessel.

  (9) The outer tube 11 may be inserted into the blood vessel as it is without using a guiding catheter. That is, the outer tube 11 may function as a sheath. Even in this case, the same effect as that of the above embodiment can be obtained.

  Further, the suction catheter 10 may not include the outer tube 11. In this case, a guiding catheter for guiding the suction catheter 10 to the treatment target site may be used in place of the outer tube 11. That is, after inserting the guiding catheter to the front of the site to be treated, the elastic tube 32 of the inner tube 12 is passed through the inner tube 12 in the above embodiment into the lumen of the guiding catheter, and the distal end of the guiding catheter is inserted. It protrudes further to the distal side than the end opening. Even with this configuration, it is possible to satisfy both conflicting demands for improving workability for insertion into and removal from a living body, and improving workability for sucking and removing thrombus.

  Moreover, you may make it insert the inner tube 12 in the said embodiment in the blood vessel independently. Even in this case, the elastic deforming portion 32 is in a state of being reduced in diameter in accordance with the inner diameter of the blood vessel, so that it can be inserted into the treatment target site. Since it is in close contact with the inner peripheral surface of the blood vessel, thrombus can be sucked and removed well. However, in such a use, the followability to the blood vessel at the time of insertion work is required as a function of the elastic deformation part 32, and there is a possibility that the design of the elastic deformation part 32 becomes difficult as compared with the above embodiment. is there.

1 is a schematic overall side view of a suction catheter. FIG. Explanatory drawing for demonstrating the structure of the area | region C in FIG. Explanatory drawing for demonstrating the structure of the area | region C in FIG. Explanatory drawing for demonstrating the usage method of the catheter for suction. Explanatory drawing for demonstrating another catheter for suction. Explanatory drawing for demonstrating another catheter for suction. Explanatory drawing for demonstrating another catheter for suction.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Suction catheter, 11 ... Outer tube, 12 ... Inner tube, 21 ... Lumen, 32 ... Elastic deformation part as a deformation part, 43 ... Suction port, 42 ... Through-hole part, 45 ... Outer peripheral surface, 60 ... For suction Catheter, 61 ... outer tube, 62 ... inner tube, 64 ... balloon.

Claims (11)

It has a suction tube with a suction lumen formed,
The suction tube has a deformable portion at its distal end that can be deformed into a contracted state and an expanded state,
When the deforming part is in the expanded state, the suction port of the lumen is in an expanded state as compared with the region closer to the lumen, and when the deforming part is in the contracted state, the suction tube is used. The suction catheter is characterized in that the outer peripheral surface thereof is contracted at the distal end portion more than the expanded state.   The said deformation | transformation part is formed so that it may be elastically deformed, and it may be urged | biased by the said urging | biasing state side with the urging | biasing force in the said contraction state. Aspiration catheter. The suction tube is inserted into the living body with the outer peripheral surface covered by the guide tube, and is movable in the longitudinal direction within the lumen of the guide tube.
In the state in which the suction tube is arranged so that the deforming portion is located in the lumen of the guide tube, the deforming portion is elastic because the outer peripheral surface of the deforming portion hits the inner peripheral surface of the guide tube. Deformed and in the contracted state,
In the state in which the suction tube is arranged so that the deformed portion protrudes from the distal end side opening of the guide tube to the distal side, the deformed portion is in the expanded state by its own biasing force. The suction catheter according to claim 2, wherein An outer tube surrounding the outside of the suction tube;
The suction tube is provided to be movable in the longitudinal direction within the lumen of the outer tube,
In the expanded state, the deformed portion has a maximum outer diameter larger than the inner diameter of the lumen of the outer tube,
In the state in which the suction tube is arranged so that the deformed portion is positioned in the lumen of the outer tube, the deformable portion is elastic because the outer peripheral surface of the deformable portion hits the inner peripheral surface of the lumen of the outer tube. Deformed and in the contracted state,
In a state where the suction tube is arranged so that the deformed portion protrudes distally from the distal end side opening of the outer tube, the deformable portion is brought into the expanded state by the self biasing force. The suction catheter according to claim 2, wherein the suction catheter is provided.   5. The suction catheter according to claim 3, wherein the deformable portion is formed such that an outer peripheral surface in the expanded state widens toward the suction port.   The suction catheter according to claim 2, wherein the deformable portion is formed of a superelastic alloy. The suction tube is for sucking a thrombus in a blood vessel,
The deformed portion is formed such that, in the expanded state, an outer peripheral surface in at least a partial region in the longitudinal direction is in close contact with an inner peripheral surface of a blood vessel to be thrombus sucked. The aspiration catheter according to any one of the above.   The suction catheter according to any one of claims 1 to 7, wherein the deformable portion has a hole portion that penetrates in the thickness direction of the deformable portion. The suction tube is for sucking a thrombus in a blood vessel,
The deforming portion is formed to be elastically deformable, and is configured to be biased toward the expanded state by its own biasing force in the contracted state,
Furthermore, the wall part which comprises a part of said lumen | rumen of the said suction tube in the said deformation | transformation part is formed with the hole part so that a blood flow may not be interrupted | blocked in the said expansion state. The suction catheter according to any one of claims 1 to 8.   The suction catheter according to claim 1, wherein the deformable portion is formed in a mesh shape.   The deformed portion is formed such that when the deformed portion is in the expanded state, a lumen of the suction tube widens toward the suction port at the distal end portion. The suction catheter according to any one of 1 to 10.

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