JP2019013668A - Aspiration catheter - Google Patents

Abstract

To improve a suction performance for sucking a thrombus blocked on a guide wire.SOLUTION: In a suction catheter (10), a shape of an edge (3b) forming a suction port (3a) is asymmetric with respect to a virtual line (C) as a symmetric axis between a most-distal end position (1a) and a most-proximal end position (1b). Also, a curved part (4a) that is curved outward than a peripheral edge (3b) is provided at the most-distal end position (1a) with a perpendicular line (D) passing a center of the virtual lien (C) as a reference.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a suction catheter.

  Conventionally, a treatment method in which a thrombus is aspirated and removed is effective as a treatment method in the case where stenosis or occlusion occurs in a blood vessel such as a blood vessel and the blood vessel is occluded by a thrombus. A catheter used for such treatment is called a suction catheter.

  In the treatment using the suction catheter, a guide wire is used to guide the suction catheter to the vicinity of the site to be sucked in the blood vessel. A suction catheter usually has a suction lumen having a suction port for sucking a suction target, and a guide wire lumen for inserting a guide wire. Therefore, when the surgeon inserts the suction catheter into the blood vessel and guides it to the target site for suction in the blood vessel, first, the operator inserts the guide wire into the blood vessel, and the distal end of the guide wire is the target site for suction. Hold in thrombus. Thereby, the route | root by a guide wire for the suction catheter to reach | attain a site | part to be suctioned is ensured. Thereafter, the proximal side of the guide wire is passed through the distal end side of the guide wire lumen of the suction catheter, and the suction catheter is inserted into the blood vessel. The suction catheter is moved in the blood vessel along the guide wire to reach the target site for suction, and the thrombus is sucked from the suction lumen. Therefore, the aspiration catheter is required to have reachability to a lesion site where a foreign object, which is a target to be suctioned, and suction performance for sucking as much of the target as possible.

  Examples of conventional suction catheters include the suction catheters described in Patent Documents 1 and 2. In the suction catheters described in Patent Documents 1 and 2, a suction port for sucking a foreign substance such as a thrombus is formed to be inclined with respect to the axis of the suction catheter.

International Publication No. 2012/014860 JP 2010-017211 A

  Here, when the outside diameter dimension of the suction catheter is increased and the suction port size is increased, the suction catheter has a higher suction performance, but it is difficult to insert the suction catheter into a peripheral site including thin blood vessels. Therefore, there is a limit to increasing the outer diameter of the suction catheter from the viewpoint of peripheral reachability. In addition, in a suction catheter with excellent peripheral reachability, it is difficult to remove a giant thrombus in a peripheral blood vessel because the suction port or suction lumen has a relatively small inner diameter.

  When the suction catheter is inserted into the blood vessel and guided to the site to be sucked into the blood vessel, the guide wire moves along the blood vessel wall, not the central portion of the blood vessel, and pierces the thrombus that is the site to be sucked. Is retained in the thrombus.

  When a suction operation is performed using a suction catheter in which the suction port is inclined with respect to the axis of the suction catheter as described in Patent Documents 1 and 2, the thrombus is satisfactorily sucked from the suction port. The However, since the guide wire lumen and the suction lumen are arranged in parallel in the suction catheter, the thrombus caught on the guide wire away from the suction port is not sufficiently sucked. Therefore, the conventional suction catheters described in Patent Documents 1 and 2 have a problem that thrombus cannot be sufficiently sucked.

  An object of one embodiment of the present invention is to realize a suction catheter with improved suction performance for a thrombus caught on a guide wire.

  In order to solve the above-described problem, a suction catheter according to an aspect of the present invention includes a suction tube including a suction lumen having a suction portion at a distal end, and the suction portion is configured with respect to an axis of the suction tube. A suction catheter having a suction port formed to be inclined, and in the suction part, when the position on the most distal end side is the first position and the position on the most proximal end side is the second position, When viewed from the distal end side in the direction of the axis, the shape of the edge forming the suction port is asymmetric with the first line connecting the first position and the second position as the axis of symmetry, and the periphery A curved portion curved outward from the edge of the first line is arranged on the first position side with respect to a perpendicular passing through the center of the first line.

  According to one aspect of the present invention, there is an effect that the suction performance for a thrombus caught on a guide wire is improved.

The schematic structure of the suction catheter used as the premise of embodiment of this invention is shown, (a) is a side view, (b) is an AA sectional view. BRIEF DESCRIPTION OF THE DRAWINGS The schematic structure of the suction catheter which concerns on Embodiment 1 of this invention is shown, (a) is sectional drawing which shows the schematic structure of the distal end side, (b) is the front which shows the schematic structure seen from the distal end side It is a figure, (c) is a bottom view which shows the schematic structure seen from the lower side, (d) is a perspective view which shows the schematic structure seen from the distal end side. It is a front view which shows the modification of the suction catheter which concerns on Embodiment 1 of this invention, and shows schematic structure seen from the distal end side. The schematic structure of the distal end side of the suction catheter concerning Embodiment 2 of this invention is shown, (a) is a front view which shows the schematic structure seen from the distal end side, (b) was seen from the side. It is a side view which shows schematic structure, (c) is a bottom view which shows schematic structure seen from lower side. It is a side view which shows the modification of the suction catheter which concerns on Embodiment 2 of this invention, and shows the schematic structure seen from the side.

(Configuration of suction catheter as a premise of the present embodiment)
First, the configuration of the suction catheter that is a premise of the present embodiment will be described. FIG. 1 shows a schematic configuration of an aspiration catheter 11 which is a premise of the present embodiment. FIG. 1 (a) is a side view, and FIG. 1 (b) is a cross-sectional view.

  As shown in FIG. 1A, the suction catheter 11 includes a suction tube 1 constituting a suction lumen and a guide wire tube 2 constituting a guide wire lumen. A suction portion 3 is provided at the distal end of the suction tube 1. The suction unit 3 has a suction port 3a for sucking a suction target such as a thrombus. The suction port 3 a is provided to be inclined with respect to the axis of the suction tube 1. Here, the suction target side in the suction catheter is the distal end side or the distal side, and the opposite side is the proximal end side or the proximal side.

  The guide wire tube 2 is provided on the suction unit 3 side of the suction tube 1. Further, the distal end of the guide wire tube 2 is located on the distal side of the position on the most distal end side (the most distal end position 1 a shown in FIG. 2) in the suction part 3. Moreover, the length of the guide wire tube 2 is 120 mm, for example.

  As shown in FIG. 1B, the wall portion of the suction tube 1 has a laminated structure including an inner layer 12, a reinforcing layer 13, and a covering layer 14. As the resin constituting the inner layer 12, a fluorine-based resin or high-density polyethylene is used. Specific examples of the resin constituting the inner layer 12 include polytetrafluoroethylene (PTFE), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene / hexafluoropropylene copolymer (FEP), tetra Examples include fluoroethylene / ethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), and polychlorotrifluoroethylene (PCTFE).

  The reinforcing layer 13 has a braided shape in which strands are alternately knitted in a mesh shape. Examples of the material of the strands of the reinforcing layer 13 include synthetic fibers such as nylon fibers, and metals such as Ti—Ni and stainless steel.

  The covering layer 14 is a layer that covers the inner layer 12 and the braided reinforcing layer 13. An elastomer is used as the resin constituting the coating layer 14. Specific examples of the resin constituting the coating layer 14 include a polyamide elastomer, a polyester elastomer, and a polyolefin elastomer.

Embodiment 1
The suction catheter according to this embodiment is characterized by the structure of the distal end side of the suction catheter 11 shown in FIG. (A) of FIG. 2 is sectional drawing which shows schematic structure of the distal end side of the suction catheter 10 which concerns on this embodiment. FIG. 2B is a front view showing a schematic configuration viewed from the distal end side of the suction catheter 10 according to the present embodiment. FIG. 2C is a bottom view showing a schematic configuration viewed from the lower side of the suction catheter 10 according to the present embodiment. (D) of Drawing 2 is a perspective view showing a schematic structure seen from a distal end side of suction catheter 10 concerning this embodiment.

  In the suction catheter 10, the suction part 3 has a suction port 3 a formed to be inclined with respect to the axis X of the suction tube 1. For this reason, the suction portion 3 on the distal end side of the suction catheter 10 includes the most distal end position 1a (first position) on the most distal end side and the most proximal end position 1b (on the most proximal end side). A second position) exists.

  Since the guide wire is often arranged along the blood vessel wall in the blood vessel, the most distal end position 1a adjacent to the guide wire tube 2 is arranged at the most blood vessel wall side in the suction port 3a. On the other hand, the proximal end position 1b is arranged at a position farthest from the blood vessel wall.

  The shape of the suction part 3 in the vicinity of the most distal end position 1a is inclined downward toward the most proximal end position 1b. In addition, the shape of the suction part 3 in the vicinity of the most proximal end position 1b is inclined upward toward the most distal end position 1a. If the vicinity of the most distal end position 1a is a nose, the vicinity of the nearest end position 1b can be regarded as a jaw.

  Further, in the present specification, with the axis X of the suction tube 1 as a reference, the most distal end position 1a side in the suction part 3 is set as the upper side, and the side opposite to the upper side is set as the lower side. The upper side can also be said to be the side of the suction catheter 10 on which the guide wire tube 2 is provided. The side opposite to the guide wire tube 2 can be said to be the lower side.

  Also, the direction of the axis X of the suction tube 1 is the longitudinal direction (first direction), the direction of the line passing through the most proximal end position 1b and perpendicular to the axis X is the vertical direction (second direction), A direction perpendicular to both the vertical direction is a width direction (third direction).

  As shown in FIG. 2B, the suction catheter 10 according to the present embodiment has a shape of an edge 3b that forms the suction port 3a when viewed from the distal end side in the longitudinal direction that is the direction of the axis X. Asymmetrical with respect to an imaginary line C (first line) connecting the most distal end position 1a and the most proximal end position 1b. The shape of the edge 3b viewed from the distal end side has curved portions 4a and 4b. The curved portions 4a and 4b have a shape curved outward from the surrounding edge 3b. In other words, in FIG. 2B showing a front view of the suction catheter 10 seen from the distal end side, the distance between the center O of the imaginary line C and the edge 3b is the center O and the most distal end position 1a. The portions larger than the distance (corresponding to half the length of the imaginary line C) are provided as the curved portions 4a and 4b.

  Further, when the edge 3b is viewed from the distal end side, one of the two curved portions 4a and 4b is configured such that one of the curved portions 4a is based on the perpendicular D passing through the center O of the imaginary line C. It is arranged on the position 1a side. The other curved portion 4b is arranged on the closest end position 1b side with respect to the perpendicular D. The bending portion 4b is arranged on the opposite side to the bending portion 4a with the center O of the imaginary line C as a reference.

  Further, as shown in FIGS. 2C and 2D, the curved portions 4 a and 4 b are provided from the suction port 3 a to the side wall 1 c of the suction lumen A of the suction tube 1. 2 (c) and (d), the curved portions 4a and 4b are formed in the side wall 1c of the suction lumen A, and are longitudinal from the distal end side to the proximal end side of the suction port 3a. It can be grasped as a recess extending in the direction. It should be noted that the curved portions 4a and 4b as the concave portions may be provided over the side wall 1c of the suction lumen A in at least a portion from the most distal end position 1a to the most proximal end position 1b. For example, the curved portions 4a and 4b are provided on the side wall 1c of the suction lumen A from the most proximal end position 1b to the position of 10 mm toward the proximal end.

  Further, as shown in FIGS. 2A to 2D, the guide wire tube 2 having the guide wire lumen B is provided so as to be parallel to the axis X of the suction tube 1. When the suction catheter 10 is viewed from the distal end side in the longitudinal direction (in FIG. 2B), the axis Y of the guide wire tube 2, the most distal end position 1a, and the most proximal end position 1b are identical. It is arranged to line up on the line. As used herein, “colinear” refers to the axis Y, the most distal end position 1a, and the most proximal end position 1b within the positioning limits of the axis Y, the most distal end position 1a, and the most distal end position 1b. Means that they are aligned on the same straight line.

  By the way, in the suction catheter 10 provided with the suction port 3a inclined with respect to the axis X of the suction tube 1, the shape of the edge 3b forming the suction port 3a when viewed from the distal end side in the longitudinal direction is an imaginary line. When C is symmetric with respect to the symmetry axis (for example, in the case of the configuration described in Patent Documents 1 and 2), the suction pressure at the suction port 3a has a symmetric distribution with the virtual line C as the symmetry axis. The suction pressure at the most proximal end position 1b is the highest, and the suction pressure at the most distal end position 1a is the lowest. As a result, in the region surrounded by the edge 3b of the suction port 3a, with respect to the perpendicular D, the region between the region on the most distal end position 1a side (upper side) and the region on the most proximal end position 1b side (lower side) This creates a difference in suction pressure.

  In a state where such a difference in suction pressure occurs, for example, when a thrombus having the same size as that of the suction port 3a and having a large amount of fiber is sucked into the suction port 3a, the proximal end position 1b is caused by the difference in suction pressure. The thrombus existing in the region on the side is preferentially aspirated, and the thrombus existing in the region on the most distal end position 1a side remains in the blood vessel. Therefore, when viewed from the distal end side, when the shape of the edge 3b forming the suction port 3a is symmetric with respect to the imaginary line C, the thrombus existing in the region on the most distal end position 1a side is sucked. Since it becomes difficult, the attraction | suction performance with respect to the thrombus caught on the guide wire becomes very low.

  Then, a space is generated in the blood vessel when the thrombus existing in the region of the proximal end position 1b is sucked and removed to some extent from the suction port 3a. At this time, the thrombus caught on the guide wire moves into this space, and is sucked as a large lump through the region on the most proximal end position 1b side in the suction port 3a. For this reason, the suction lumen A may be blocked by such a large lump of thrombus.

  According to the suction catheter 10 according to the present embodiment, as shown in FIG. 2B, the shape of the edge 3b forming the suction port 3a is asymmetric with the virtual line C as the axis of symmetry. Therefore, the suction pressure at the suction port 3a has an asymmetric distribution with the virtual line C as the axis of symmetry. For this reason, in the suction port 3a, a difference in suction pressure occurs between the two regions A1 and A2 divided by the virtual line C.

  Further, when the curved portions 4a and 4b that are curved outward are formed on the edge 3b, the distribution of the suction pressure at the suction port 3a is such that the suction pressure at the curved portions 4a and 4b is relatively high. . In the suction catheter 10 according to the present embodiment, the bending portion 4a is disposed on the most distal end position 1a side (that is, the upper side) with respect to the perpendicular D as shown in FIG. The suction pressure in the region above the perpendicular D in the mouth 3a can be increased. As a result, the suction pressure in the region on the most distal end position 1a side can be increased with the perpendicular D as a reference, and the suction pressure difference between the region on the most distal end position 1a side and the region on the most proximal end position 1b side can be reduced. can do. Therefore, in the suction catheter 10 according to the present embodiment, the thrombus is easily sucked from the region on the most distal end position 1a side in the suction port 3a as compared with the conventional suction catheter, and the thrombus caught on the guide wire The suction performance against is improved. Furthermore, the suction catheter 10 in which the suction lumen A is not easily blocked by a thrombus can be realized.

  Here, when the shape of the edge 3b forming the suction port 3a is symmetric with respect to the imaginary line C, even if the curved portions 4a and 4b are formed on the edge 3b, the suction pressure at the curved portions 4a and 4b. Is not relatively high. This is because the shape of the edge 3b is symmetric with respect to the virtual line C, so that the suction pressure distribution is not disturbed. In the suction catheter 10 according to the present embodiment, the shape of the edge 3b forming the suction port 3a is asymmetric with respect to the virtual line C, thereby disturbing the suction pressure distribution at the suction port 3a. . Then, the shape of the edge 3b is changed to a shape that causes disturbance in the suction pressure distribution, and the curved portions 4a and 4b that are curved outward are formed on the edge 3b. The suction pressure is increased.

  In the configuration shown in FIGS. 2A to 2D, two curved portions 4a and 4b are formed on the edge 3b. However, the suction catheter 10 according to the present embodiment is not limited to the configuration shown in FIGS. 2A to 2D, and is a curved portion that can distribute the suction pressure higher in the region above the perpendicular D. Any number and arrangement may be used. For example, a configuration in which only the curved portion 4a on the most distal end position 1a side with respect to the perpendicular line D is formed on the edge 3b may be employed.

  A plurality of bending portions may be provided, but preferably two are provided. When two bending portions are provided, the positional relationship between the bending portions 4a and 4b shown in FIG. 2B is preferable. That is, it is preferable that the bending portion 4b is disposed at a position away from the bending portion 4a, and it is particularly preferable that the bending portion 4b is disposed on the opposite side of the bending portion 4a with respect to the center O of the imaginary line C.

(Modification)
In the configuration of the suction catheter 10 according to the present embodiment, a modified example of the configuration shown in FIGS. 2A to 2D will be described. FIG. 3 is a front view showing a schematic configuration as viewed from the distal end side of the suction catheter 10A as a modified example.

  As shown in FIG. 3, the suction catheter 10A is different from the configuration shown in FIGS. 2A to 2D in that the shape of the edge 3b forming the suction port 3a is elliptical. In the suction catheter 10A, the vertices 4c and 4d in the direction of the long axis E in the ellipse formed by the edge 3b function as the above-described bending portion. Further, the intersection of the major axis E and the minor axis F of the ellipse formed by the edge 3b coincides with the center O of the imaginary line C connecting the most distal end position 1a and the most proximal end position 1b. The elliptical shape formed by the edge 3b is configured such that the major axis E intersects the virtual line C, and is asymmetric with the virtual line C as the axis of symmetry. Of the vertices 4c and 4d, the vertex 4c is arranged on the most distal end position 1a side with respect to the perpendicular D.

  Since the vertices 4c and 4d function as the curved portion described above, the suction pressure in the region on the most distal end position 1a side with respect to the perpendicular D can be increased, which is shown in FIGS. 2 (a) to (d). The same effect as the suction catheter 10 is obtained.

  In the suction catheter 10A, the major axis / minor axis, which is the ratio of the length (major axis) of the major axis E to the length (minor axis) of the minor axis F in the ellipse formed by the edge 3b, is expressed by the apexes 4c and 4d. Any ratio may be used as long as it functions as the bending portion described above. Specifically, the major axis / minor axis is preferably 11/9 to 3/1, and more preferably 3/2 to 2/1.

  In addition, the inclination angle θ of the major axis E with respect to the virtual line C may be an inclination angle that allows the vertices 4c and 4d to function as the above-described bending portion. Specifically, the inclination angle θ is preferably 5 ° to 85 °, and more preferably 30 ° to 45 °.

  In addition, the suction catheter 10 which concerns on this embodiment can be manufactured with the following manufacturing method, for example. First, a cylindrical metal core material having a cross section in the shape of the edge 3b shown in FIG. 2B or FIG. 3 is inserted into the suction tube material to be the suction tube 1. Then, heat processing and cooling are performed below the melting point of the suction tube material. And the suction tube 1 by which the curved parts 4a and 4b were formed in the edge 3b of the suction port 3a is obtained by drawing out the said metal core material from suction tube material. Thereafter, the obtained suction tube 1 and guide wire tube 2 are welded by a conventional method. And about this welded body, the distal end part of a welded body is excised so that the opening of the distal end side of the suction tube 1 may become the suction port 3a which inclined. For example, when manufacturing the suction catheter 10A shown in FIG. 3, a cylindrical member having an elliptical cross section is used as the metal core.

[Embodiment 2]
Hereinafter, other embodiments of the present invention will be described in detail. 4 shows a schematic configuration of the distal end side of the suction catheter 10B according to the present embodiment, and FIG. 4A is a front view showing a schematic configuration viewed from the distal end side. FIG. 4B is a side view showing a schematic configuration viewed from the side, and FIG. 4C is a bottom view showing the schematic configuration viewed from below. For convenience of explanation, members having the same functions as those described in the embodiment are given the same reference numerals, and descriptions thereof are omitted.

  In the suction catheter 10B according to the present embodiment, as shown in FIG. 4A, the shape of the edge 3b forming the suction port 3a is symmetric with respect to the imaginary line C as viewed from the distal end side in the longitudinal direction. And is the same as that of the first embodiment in that the curved portions 4a and 4b are provided.

  In the suction catheter 10B according to this embodiment, as shown in FIG. 4C, the shape of the edge 3b forming the suction port 3a is asymmetric with the virtual line C as the axis of symmetry when viewed from below in the vertical direction. This is different from the first embodiment.

  Here, the two parts of the edge 3b that are divided with the virtual line C as a reference are defined as a first edge 3c and a second edge 3d. At this time, as shown in FIG. 4B, the shape of the edge 3b forming the suction port 3a is such that the first edge 3c and the second edge 3d are at least as viewed from the width direction (third direction). There is a part that does not overlap in one part.

  The edge shape of the suction port 3a shown in FIGS. 4A to 4C is cut out when the distal end portion of the welded body of the suction tube 1 and the guide wire tube 2 is cut to form the suction port 3a. It is possible to form by setting the moving direction etc. of the blade member used for this.

  For example, the suction tube 1 is suctioned by moving the knife-like blade member to the distal end side along the imaginary line C while maintaining the state where the blade tip is inclined with respect to the axis X. A mouth 3a is formed. At this time, by maintaining the state where the blade edge is inclined with respect to both the width direction and the direction of the axis X (longitudinal direction), the blade member is moved to the distal end side along the track along the imaginary line C. The edge shape of the suction port 3a shown in FIGS. 4A to 4C is formed.

  Here, in the suction catheter 10 provided with the suction port 3a inclined with respect to the axis X of the suction tube 1, the shape of the edge 3b forming the suction port 3a when viewed from the most proximal end position 1b in the vertical direction. Even when the imaginary line C is symmetric with respect to the symmetry axis, the suction pressure at the suction port 3a has a symmetric distribution with the imaginary line C as the symmetry axis. The suction pressure at the most proximal end position 1b is the highest, and the suction pressure at the most distal end position 1a is the lowest.

  The suction catheter 10B according to the present embodiment has a configuration that also takes into account the edge shape of the suction port 3a as viewed from the closest position 1b in the vertical direction.

  According to the suction catheter 10B according to the present embodiment, the shape of the edge 3b forming the suction port 3a is asymmetric with the virtual line C as the axis of symmetry when viewed from the lower side in the vertical direction. Disturbance occurs in the pressure distribution. For this reason, the suction pressure distribution at the suction port 3a is asymmetric with respect to the imaginary line C as an axis of symmetry, and between the region on the most distal end position 1a side and the region on the most proximal end position 1b side with respect to the perpendicular line D. The suction pressure difference becomes smaller. As a result, in the suction catheter 10 according to the present embodiment, the suction pressure in the region on the most distal end position 1a side in the suction port 3a is larger than that in the conventional suction catheter, and therefore, the distalmost end position 1a. The thrombus present on the side is easily sucked, and the suction performance for the thrombus caught on the guide wire is improved.

  Further, in order to increase the suction pressure in the region on the most distal end position 1a side in the suction port 3a, the length of the first edge 3c is preferably more than one time the length of the second edge 3d, It is not more than 3 times, and more preferably not less than 1.2 times and not more than 1.8 times the length of the second edge 3d.

(Modification)
In the configuration of the suction catheter 10B according to the present embodiment, a modified example of the configuration shown in FIGS. 4A to 4C will be described. FIG. 5 is a side view showing a schematic configuration viewed from the side of a suction catheter 10C as a modified example.

  The shape of the edge 3b of the suction port 3a of the suction catheter 10C is different from the configuration shown in FIGS. 4 (a) to (c). As shown in FIG. 5, when viewed from the width direction, the shape of the edge 3 b including the first edge 3 c and the second edge 3 d is a shape curved toward the proximal end side from the imaginary line C.

  By adopting such a configuration, even if the suction catheter 10C has a small diameter in the vertical direction, the size of the suction port 3a capable of sucking the thrombus can be secured.

[Summary]
A suction catheter 10 according to an embodiment of the present invention includes a suction tube 1 including a suction lumen A having a suction portion 3 at a distal end, and the suction portion 3 is inclined with respect to the axis X of the suction tube 1. A suction catheter 10 having a suction port 3a formed as described above, in the suction portion 3, the most distal end position 1a on the most distal end side is set as the first position, and the most proximal end position 1b on the most proximal end side. Is the second position, the shape of the edge 3b forming the suction port 3a when viewed from the distal end side in the direction of the axis X is the first line (imaginary line C) connecting the first position and the second position. ) As a symmetric axis, and the curved portion 4a curved outward from the surrounding edge 3b is located on the first position side with respect to the perpendicular D passing through the center O of the first line (virtual line C). It is the composition which is arranged.

  According to said structure, the shape of the edge 3b which forms the suction port 3a is asymmetrical about the virtual line C as an axis of symmetry. Therefore, the suction pressure at the suction port 3a has an asymmetric distribution with the virtual line C as the axis of symmetry. For this reason, in the suction port 3a, a difference in suction pressure occurs between the two regions A1 and A2 divided by the virtual line C.

  Furthermore, when the curved portion 4a curved outward is formed on the edge 3b, the distribution of the suction pressure at the suction port 3a is such that the suction pressure at the curved portion 4a is relatively high. According to said structure, since the bending part 4a is distribute | arranged to the 1st position side (namely, the most distal end position 1a side) on the basis of the perpendicular D, it is a 1st position side rather than the perpendicular D in the suction opening 3a. The suction pressure in the region can be increased. As a result, the suction pressure in the region on the first position side can be increased with the perpendicular D as a reference, and the difference in suction pressure between the region on the first position side and the region on the second position side can be reduced. Therefore, according to the above configuration, compared to the conventional suction catheter, the thrombus is easily sucked from the region on the most distal end position 1a side in the suction port 3a, and the suction performance with respect to the thrombus caught on the guide wire Will improve.

  In the suction catheter 10 according to an embodiment of the present invention, another bending portion 4b may be further arranged on the opposite side of the bending portion 4a with respect to the center O of the first line.

  Even if it is said structure, compared with the conventional suction catheter, a thrombus becomes easy to be attracted | sucked from the area | region of the most distal end position 1a side in the suction port 3a.

  In the suction catheter 10 according to an embodiment of the present invention, the bending portion 4a is provided over the side wall 1c of the suction lumen A at least in a portion between the first position and the second position. It may be.

  According to the above configuration, since the curved portion 4a is provided not only at the edge 3b of the suction port 3a but also at the side wall 1c of the suction lumen A, the suction pressure in the region on the first position side is more reliably increased. it can.

  Further, in the suction catheter 10A according to one embodiment of the present invention, the shape of the edge 3b forming the suction port 3a is an elliptical shape when viewed from the distal end side in the direction of the axis X, and A configuration in which one of the vertices 4c and 4d in the major axis direction (the direction of the major axis E) (vertex 4c) is arranged on the first position side with respect to the perpendicular D may be employed.

According to said structure, when the vertex 4c and 4d function as a curved part mentioned above, the suction pressure in the area | region of the most distal end position 1a side rather than the perpendicular D can be made high.

  In the suction catheter 10B according to the embodiment of the present invention, the direction of the axis X is the first direction (longitudinal direction), and the direction of the line that passes through the second position and is perpendicular to the axis X is the second. The suction port 3a is a direction (vertical direction), and a direction perpendicular to both the first direction and the second direction is a third direction (width direction) when viewed from the second position side in the second direction. The shape of the edge 3b forming the shape may be asymmetric with respect to the first line.

  According to the above configuration, since the shape of the edge 3b forming the suction port 3a is asymmetric with respect to the first line when viewed from the second position side in the second direction, the suction at the suction port 3a. Disturbance occurs in the pressure distribution. For this reason, the suction pressure distribution at the suction port 3a is asymmetric with respect to the first line as the axis of symmetry, and the region on the most distal end position 1a side and the region on the most proximal end position 1b side with respect to the perpendicular D as a reference. The suction pressure difference between them becomes smaller. Therefore, according to the above configuration, the suction pressure in the region on the first position side can be increased.

  Further, in the suction catheter 10B according to an embodiment of the present invention, when the two portions of the edge 3b that are sectioned on the basis of the first line are the first edge 3c and the second edge 3d, the suction port 3a. The shape of the edge 3b forming the shape may be a configuration in which at least one portion of the first edge 3c and the second edge 3d does not overlap when viewed from the third direction.

  According to the above configuration, the shape of the edge 3b forming the suction port 3a is asymmetric with respect to the first line when viewed from the second position side in the second direction. The suction pressure in the area can be increased.

  In the suction catheter 10C according to the embodiment of the present invention, the shape of the edge 3b forming the suction port 3a is closer to the proximal end of the suction tube 1 than the first line when viewed from the third direction. The shape is preferably curved to the side.

  Thereby, even if the suction catheter 10C has a small diameter with a small vertical dimension, the size of the suction port 3a capable of sucking the thrombus can be secured.

  Further, in the suction catheter 10B according to an embodiment of the present invention, when the two portions of the edge divided with respect to the first line are defined as the first edge 3c and the second edge 3d, the first edge 3c. It is preferable that the length of is more than 1 time of the length of the said 2nd edge 3d, and is 3 times or less.

  By setting the dimensions of the first edge 3c and the second edge 3d as in the above configuration, the suction pressure in the region on the first position side in the suction port 3a can be increased.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

1 Suction tube 1a The most distal end position (first position)
1b Nearest end position (second position)
1c side wall 2 guide wire tube 3 suction part 3a suction port 3b edge 3c first edge 3d second edge 4a, 4b curved part 4c, 4d apex 10, 10A, 10B, 10C suction catheter A suction lumen B guide wire lumen C virtual line (Line 1)
D perpendicular X axis O center

Claims (8)

Comprising a suction tube with a suction lumen having a suction part at the distal end;
The suction part is a suction catheter having a suction port formed to be inclined with respect to the axis of the suction tube,
In the suction part, when the position on the most distal end side is the first position and the position on the most proximal end side is the second position,
Seen from the distal end in the direction of the axis,
The shape of the edge forming the suction port is:
Asymmetric with respect to a first line connecting the first position and the second position, and
A suction catheter, wherein a curved portion that is curved outward from a peripheral edge is disposed on the first position side with respect to a perpendicular passing through the center of the first line.   The suction catheter according to claim 1, wherein another bending portion is further arranged on the opposite side of the bending portion with respect to the center of the first line.   The suction catheter according to claim 1, wherein the curved portion is provided over a side wall of the suction lumen at least in a portion between the first position and the second position. Seen from the distal end in the direction of the axis,
The shape of the edge forming the suction port is an elliptical shape, and any one of the vertices in the major axis direction of the ellipse is arranged on the first position side with respect to the perpendicular. The suction catheter according to any one of 1 to 3. The axial direction is the first direction, the direction of the line passing through the second position and perpendicular to the axial line is the second direction, and the direction perpendicular to both the first direction and the second direction is the third direction. As
Seen from the second position side in the second direction,
The suction catheter according to any one of claims 1 to 4, wherein the shape of the edge forming the suction port is asymmetric with respect to the first line. When the two parts of the edge divided with respect to the first line as a first edge and a second edge,
The shape of the edge that forms the suction port includes at least a portion where the first edge and the second edge do not overlap when viewed from the third direction. Aspiration catheter.   The shape of the edge forming the suction port is a shape curved toward the proximal end side of the suction tube with respect to the first line as viewed from the third direction. The aspiration catheter as described. When the two parts of the edge divided with respect to the first line as a first edge and a second edge,
8. The suction catheter according to claim 5, wherein the length of the first edge is more than 1 time and not more than 3 times the length of the second edge. 9.

Images