JPWO2019012819A1 - Suction catheter - Google Patents

Abstract

In order to improve the suction performance for the thrombus caught on the guide wire, the shape of the edge (3b) forming the suction port (3a) in the suction catheter (10) is the most distal when viewed from below in the vertical direction. It is asymmetric with respect to an imaginary line (C) connecting the end position (1a) and the nearest end position (1b).

Description

  The present invention relates to suction catheters.

  Conventionally, as a treatment method when stenosis or occlusion occurs in a blood vessel such as a blood vessel, and when a blood vessel is occluded by a thrombus, a treatment method of sucking and removing the thrombus is effective. The catheter used for such treatment is called a suction catheter.

  In the treatment using a suction catheter, a guide wire is used to guide the suction catheter to the vicinity of a suction target site in a blood vessel. A suction catheter usually has a suction lumen having a suction port for sucking an object to be sucked, and a guide wire lumen for inserting a guide wire. Therefore, when the operator inserts the suction catheter into the blood vessel and guides it to the suction target site in the blood vessel, first, the guide wire is inserted into the blood vessel, and the distal end of the guide wire is the suction target site. Allow the blood clot to hold. This secures a guide wire route for the suction catheter to reach the target site for suction. After that, 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 suction target site, and the thrombus is suctioned from the suction port. Therefore, the suction catheter is required to have reachability to a lesion site where a foreign object to be suctioned exists and suction performance for sucking as many objects as possible.

  Examples of conventional suction catheters include 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. 2008/123521 JP, 2004-222946, A

  Here, when the outer diameter of the suction catheter is increased and the size of the suction port is increased, the suction performance of the suction catheter is increased, but it is difficult to insert the suction catheter even to a peripheral portion including a thin blood vessel. Therefore, there is a limit to increase the outer diameter of the suction catheter from the viewpoint of peripheral accessibility. Further, with a suction catheter having excellent peripheral accessibility, it is difficult to remove a huge thrombus in a peripheral blood vessel because the suction port or suction lumen has a relatively small inner diameter.

  When inserting the suction catheter into the blood vessel and guiding it to the target site for suction in the blood vessel, the guide wire moves not along the central part of the blood vessel but along the wall of the blood vessel and pierces the thrombus, which is the target site for suction, to terminate the distal end. Are retained in the blood clot.

  When the suction operation is performed using the suction catheter having the suction port inclined with respect to the axis of the suction catheter as described in Patent Documents 1 and 2, the thrombus is satisfactorily suctioned from the suction port. It 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 separated from the suction port is not sufficiently sucked. Therefore, the conventional suction catheters described in Patent Documents 1 and 2 have a problem that the 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 thrombus caught on a guide wire.

  In order to solve the above problems, the suction catheter according to one 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 relative to an axis of the suction tube. A suction catheter having a suction port formed to be inclined, wherein the most distal end side position is the first position and the most proximal end side position is the second position in the suction part, A direction of the axis is a first direction, a direction of a line passing through the second position and perpendicular to the axis is a second direction, and a direction perpendicular to both the first direction and the second direction is a third direction. As for the direction, the shape of the edge forming the suction port is asymmetric with respect to the first line connecting the first position and the second position when viewed from the second position side in the second direction. It is characterized by

  According to one aspect of the present invention, there is an effect that 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 a sectional view on the AA line. The schematic structure of the suction catheter which concerns on Embodiment 1 of this invention is shown, (a) is a front view which shows the schematic structure seen from a distal end side, (b) shows the schematic structure seen from a side. It is a side view, and (c) is a bottom view showing a schematic configuration as viewed from below. It is a side view which shows the modification of the suction catheter which concerns on Embodiment 1 of this invention, and shows the schematic structure seen from the side. The schematic structure by the side of a distal end of the suction catheter which concerns on Embodiment 2 of this invention is shown, (a) is a front view which shows the schematic structure seen from the distal end side, (b) is seen from a side. 2C is a side view showing the schematic configuration shown in FIG. 1, FIG. 7C is a bottom view showing the schematic configuration seen from the lower side, and FIG. 6D is a perspective view showing the schematic configuration seen from the distal end side. e) is a cross-sectional view showing a schematic configuration on the distal end side. It is a front 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 distal end side.

(Structure of the suction catheter which is the premise of this embodiment)
First, the structure of the suction catheter which is the premise of the present embodiment will be described. 1A and 1B show a schematic configuration of a suction catheter 11 which is a premise of the present embodiment. FIG. 1A is a side view and FIG. 1B is a sectional view.

  As shown in FIG. 1A, the suction catheter 11 includes a suction tube 1 that constitutes a suction lumen and a guide wire tube 2 that constitutes a guide wire lumen. A suction unit 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 3a is provided so as to be inclined with respect to the axis of the suction tube 1. Here, the suction target side of 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 section 3 side of the suction tube 1, that is, on the distal side. Further, the distal end of the guide wire tube 2 is located on the distal side of the most distal end side position (the most distal end position 1a shown in FIG. 2) of the suction section 3. The length of the guide wire tube 2 is 120 mm, for example. The length of the suction tube 1 is, for example, 140 cm, and the diameter of the tube is, for example, 1.1 mm. The diameter of the guide wire tube is 0.4 mm, for example. The distal end of the guide wire tube 2 may be located at the same position as the most distal end side of the suction section 3 or at a position proximal to the position.

  Moreover, 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 coating layer 14. As the resin forming the inner layer 12, a fluorine resin or high density polyethylene is used. Specific examples of the resin forming the inner layer 12 include polytetrafluoroethylene (PTFE), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene / hexafluoropropylene copolymer (FEP), and tetra. Examples thereof include fluoroethylene / ethylene copolymer (ETFE), polyvinylidene fluoride (PVDF) and polychlorotrifluoroethylene (PCTFE).

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

  The coating layer 14 is a layer that covers the inner layer 12 and the braided reinforcing layer 13. An elastomer is used as the resin forming the coating layer 14. Specific examples of the resin forming the coating layer 14 include polyamide elastomer, polyester elastomer, polyolefin elastomer and the like. The total number, thickness, and material of the laminated structure of the tube can be appropriately designed according to the required function. For example, a structure having only one layer, a structure in which the inner layer 12, the reinforcing layer 13, and the coating layer 14 are made of the same material, a structure without the reinforcing layer 13, and the like are also mentioned as the embodiments of the present invention.

[Embodiment 1]
The suction catheter according to this embodiment is characterized by the structure on the distal end side of the suction catheter 11 shown in FIG. FIG. 2A is a front view showing the schematic configuration of the suction catheter 10 according to the present embodiment as seen from the distal end side. FIG. 2B is a side view showing a schematic configuration as viewed from the side. FIG. 2C is a bottom view showing a schematic configuration seen from the lower side.

  In the suction catheter 10, the suction unit 3 has a suction port 3a that is formed to be inclined with respect to the axis X of the suction tube 1. Therefore, in the suction portion 3 on the distal end side of the suction catheter 10, the most distal end position 1a on the most distal end side (first position) and the most proximal end position 1b on the most proximal end side ( Second position) is present.

  Within blood vessels, guidewires are often placed along the vessel wall. When the guide wire is arranged along the blood vessel wall, the most distal end position 1a adjacent to the guide wire tube 2 is arranged closest to the blood vessel wall at the suction port 3a. On the other hand, the nearest end position 1b is arranged at the position farthest from the blood vessel wall.

  The shape of the suction portion 3 near the most distal end position 1a is a shape that is inclined downward toward the most proximal end position 1b. The shape of the suction portion 3 near the most proximal end position 1b is a shape that is inclined upward toward the most distal end position 1a. If the portion near the most distal end position 1a is the nose, the portion near the most proximal end position 1b can be regarded as the jaw.

  Further, in the specification of the present application, with the axis X of the suction tube 1 as a reference, the most distal end position 1a side of the suction portion 3 is the upper side, and the opposite side to the upper side is 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.

  In addition, the direction of the axis X of the suction tube 1 is the longitudinal direction (first direction), and the direction of a straight line passing through the most proximal end position 1b of the suction portion 3 and orthogonal to the axis X is the vertical direction (second direction). The direction perpendicular to both the longitudinal direction and the vertical direction is the width direction (third direction). It should be noted that the up-down direction can be said to be a direction of a perpendicular line of the axis line X that passes through the most proximal position 1b.

  In the suction catheter 10 according to the present embodiment, as shown in FIG. 2C, the shape of the edge 3b forming the suction port 3a is the most distal end position 1a when viewed from below in the vertical direction. It is asymmetric with respect to an imaginary line C (first line) that is a straight line connecting the most proximal end position 1b.

  Here, the two parts of the edge 3b that are sectioned with the virtual line C as a reference are referred to as a first edge 3c and a second edge 3d. At this time, as shown in FIG. 2B, the shape of the edge 3b forming the suction port 3a is such that at least the first edge 3c and the second edge 3d are seen in the width direction (third direction). There are some parts that do not overlap.

  The edge shape of the suction port 3a shown in FIGS. 2A to 2C forms the suction port 3a by cutting the welded body of the suction tube 1 and the guide wire tube 2 and the distal end portion of the suction tube 1. In doing so, it can be formed by setting the moving direction and the like of the blade member used for cutting.

  For example, the suction tube 1 is sucked by moving the knife-shaped blade member to the distal end side along an orbit along the imaginary line C while maintaining the state where the blade tip is inclined with respect to the axis X. The mouth 3a is formed. At this time, by moving the blade member to the distal end side along the track along the imaginary line C while 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 edge shape of the suction port 3a shown in FIGS. 2A to 2C is formed.

  Further, as shown in FIGS. 2A to 2C, 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 ((a) of FIG. 2), the axis Y of the guide wire tube 2, the most distal end position 1a, and the most proximal end position 1b are in the same straight line. It is arranged to line up on the line. The term "on the same straight line" as used herein means that the axis Y, the most distal end position 1a, and the most proximal end position 1b are within the position measurement limits of the axis Y, the most distal end position 1a, and the most proximal end position 1b. Means that are lined up on the same straight line. The "position measurement limit" here is the limit of the measurement error of the measuring means that measures each position of the axis Y, the most distal end position 1a, and the most proximal end position 1b, and the position measurement of the measuring means. Determined by precision.

  By the way, the suction catheter 10 has a configuration in which the suction port 3a is provided so as to be inclined with respect to the axis X of the suction tube 1. In such a configuration, when the shape of the edge 3b forming the suction port 3a is symmetrical with respect to the virtual line C as a symmetry axis when viewed from below in the vertical direction (for example, in the case of the configurations described in Patent Documents 1 and 2). ), The suction pressure at the suction port 3a has a symmetrical distribution with the imaginary line C as the axis of symmetry. The suction pressure is highest at the most proximal end position 1b, and lowest at the most distal end position 1a. As a result, in the region surrounded by the edge 3b of the suction port 3a, with respect to the perpendicular D that passes through the midpoint O of the imaginary line C and extends in the width direction, the region closest to the most distal end position 1a side (upper side) A difference in suction pressure is generated between the region on the side of the position end position 1b (lower side). The midpoint O can be said to be the center of the elongated circle when the shape of the edge 3b of the suction port 3a when viewed in the longitudinal direction is a circle, for example.

  Consider a case where a thrombus having the same size as the suction port 3a and a large amount of fibrous substance is sucked into the suction port 3a in the state where such a difference in suction pressure occurs. In this case, due to the difference in suction pressure, the thrombus present in the region on the side of the most proximal end position 1b is preferentially sucked, and the thrombus present in the region on the side of the most distal end position 1a remains in the blood vessel. Therefore, when the shape of the edge 3b forming the suction port 3a is symmetrical with respect to the virtual line C as the axis of symmetry when viewed from the lower side in the vertical direction, the thrombus present in the region on the most distal end position 1a side is sucked. Since it is less likely to be performed, the suction performance for the thrombus caught on the guide wire is extremely low.

  Then, the thrombus existing in the region of the most proximal position 1b is sucked and removed to some extent from the suction port 3a, so that a space is created in the blood vessel. At this time, the thrombus caught on the guide wire moves to this space and becomes a large mass via the region on the side of the most proximal end position 1b of the suction port 3a. Therefore, the suction lumen A may be blocked by such a large clot.

  According to the suction catheter 10 according to the present embodiment, as shown in FIGS. 2B and 2C, the shape of the edge 3b forming the suction port 3a is a virtual line when viewed from below in the vertical direction. It is asymmetric with C as the axis of symmetry. Therefore, the suction pressure distribution at the suction port 3a is disturbed. Therefore, the suction pressure distribution at the suction port 3a becomes asymmetric with the imaginary line C as the axis of symmetry, and with the perpendicular D as the reference, between the region on the side of the most distal end position 1a and the region on the side of the most proximal position 1b. Reduces the suction pressure difference. 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 of the suction port 3a becomes larger than that in the conventional suction catheter. Therefore, the thrombus existing on the most distal end position 1a side is easily sucked, and the suction performance for the thrombus caught on the guide wire is improved. Further, it is possible to realize the suction catheter 10 in which the suction lumen A is unlikely to be blocked by the thrombus.

  Further, in order to increase the suction pressure in the region of the suction port 3a on the side of the most distal end position 1a, the length of the first edge 3c preferably exceeds 1 times the length of the second edge 3d, It is 3 times or less, and more preferably 1.2 times or more and 1.8 times or less of the length of the second edge 3d.

(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 2C will be described. FIG. 3 is a side view showing a schematic configuration of the suction catheter 10A as the modified example as viewed from the side.

  The suction catheter 10A is different in the shape of the edge 3b of the suction port 3a from the configuration shown in FIGS. 2 (a) to 2 (c). As shown in FIG. 3, when viewed in the width direction, the shape of the edge 3b including the first edge 3c and the second edge 3d is curved toward the proximal end side with respect to the imaginary line C.

  With such a configuration, even if the suction catheter 10A has a small vertical dimension, the dimension of the suction port 3a capable of sucking the thrombus can be secured.

[Embodiment 2]
Hereinafter, another embodiment of the present invention will be described in detail. FIG. 4 shows a schematic configuration on the distal end side of the suction catheter 10B according to this embodiment, and FIG. 4 (a) is a front view showing the schematic configuration seen from the distal end side. (B) is a side view showing a schematic configuration as viewed from the side, (c) of FIG. 4 is a bottom view showing the schematic configuration as viewed from below, and (d) of FIG. 4 is a distal end. It is a perspective view which shows the schematic structure seen from the side, and (e) of FIG. 4 is sectional drawing which shows the schematic structure of a distal end side. For convenience of description, members having the same functions as the members described in the above embodiment will be designated by the same reference numerals, and the description thereof will be omitted.

  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 imaginary line C as the symmetry axis when viewed from the lower side in the vertical direction. Is similar to the first embodiment.

  In the suction catheter 10B according to the present embodiment, as shown in FIG. 4A, when viewed from the distal end side in the longitudinal direction, the shape of the edge 3b forming the suction port 3a is an axis of symmetry with respect to the imaginary line C. Is asymmetrical, and is different from the first embodiment in that the curved portions 4a and 4b are provided on the edge 3b. The curved portions 4a and 4b have a shape curved outward from the edge 3b around them. In other words, in FIG. 4A showing the front view of the suction catheter 10 viewed from the distal end side, the distance between the midpoint O of the imaginary line C and the edge 3b is the midpoint O and the most distal end position. Portions larger than the distance from 1a (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 has the most distal end with respect to the perpendicular D passing through the midpoint O of the imaginary line C. It is arranged on the end position 1a side. The other curved portion 4b is arranged on the side of the most proximal end position 1b with respect to the perpendicular D. The curved portion 4b is arranged on the opposite side of the curved portion 4a with respect to the midpoint O of the imaginary line C.

  Further, as shown in (b) to (e) of FIG. 4, the curved portions 4a and 4b are provided from the suction port 3a to the side wall 1c of the suction lumen A of the suction tube 1. From the configuration shown in (c) and (d) of FIG. 4, the curved portions 4a and 4b are formed in the side wall 1c of the suction lumen A, and are arranged in the longitudinal direction from the distal end side to the proximal end side of the suction port 3a. It can be regarded as a concave portion extending to. The curved portions 4a and 4b as the recesses may be provided over the side wall 1c of the suction lumen A at least 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 position 1b to the position 10 mm toward the proximal end.

  The suction catheter 10B according to the present embodiment is configured in consideration of the edge shape of the suction port 3a as viewed from the distal end side in the longitudinal direction.

  According to the suction catheter 10B of the present embodiment, as shown in FIG. 4A, 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. Therefore, at the suction port 3a, a difference in suction pressure occurs between the two areas A1 and A2 divided by the imaginary line C.

  Further, when the curved portions 4a and 4b that are curved outward are formed on the edge 3b, the suction pressure distribution in the suction port 3a is such that the suction pressure in the curved portions 4a and 4b is relatively high. .. In the suction catheter 10B according to the present embodiment, the curved portion 4a is arranged on the side of the most distal end position 1a (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 at 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 reference to the perpendicular D, and the suction pressure difference between the region on the most distal end position 1a side and the most distal end position 1b side can be made small. can do. Therefore, in the suction catheter 10B according to the present embodiment, as compared with the conventional suction catheter, the thrombus is more likely to be sucked from the region of the suction port 3a on the side of the most distal end position 1a, and the thrombus caught on the guide wire. To improve the suction performance. Furthermore, it is possible to realize the suction catheter 10B in which the suction lumen A is unlikely to be blocked by the thrombus.

  Here, when the shape of the edge 3b forming the suction port 3a is symmetrical with the virtual line C as the axis of symmetry, 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 increased. Is not relatively high. This is because the shape of the edge 3b is symmetrical with respect to the imaginary line C, so that the suction pressure distribution is not disturbed. In the suction catheter 10B according to this embodiment, the shape of the edge 3b forming the suction port 3a is asymmetric with respect to the imaginary line C, so that the suction pressure distribution at the suction port 3a is disturbed. .. Then, the edge 3b is formed in such a manner that the suction pressure distribution is disturbed, and the curved portions 4a and 4b that are curved outward are formed on the edge 3b. The suction pressure of is high.

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

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

(Modification)
In the configuration of the suction catheter 10B according to this embodiment, a modified example of the configuration shown in (a) to (e) of FIG. 4 will be described. FIG. 5: is a front view which shows schematic structure seen from the distal end side of the suction catheter 10C as this modification.

  As shown in FIG. 5, the suction catheter 10C is different from the configurations shown in FIGS. 4A to 4E in that the shape of the edge 3b forming the suction port 3a is elliptical. In the suction catheter 10C, the vertices 4c and 4d in the direction of the major axis E in the ellipse formed by the edge 3b function as the above-mentioned curved portion. The intersection of the major axis E and the minor axis F of the ellipse formed by the edge 3b coincides with the midpoint 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. Then, of the vertices 4c and 4d, the apex 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 above-mentioned curved portions, the suction pressure in the region on the side of the most distal end position 1a relative to the perpendicular D can be made higher, and this is shown in (a) to (e) of FIG. The same effect as the suction catheter 10 is obtained.

  Further, 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, has apexes 4c and 4d. The ratio may be such that it functions as the above-mentioned curved portion. Specifically, the major axis / minor axis is preferably 11/9 to 3/1, and more preferably 3/2 to 2/1.

  Further, the inclination angle θ of the long axis E with respect to the imaginary line C may be any inclination angle at which the vertices 4c and 4d function as the above-described bending portion. Specifically, the inclination angle θ is preferably 5 ° to 85 °, more preferably 5 ° to 45 °.

  The suction catheter 10B according to this embodiment can be manufactured, for example, by the following manufacturing method. First, the distal end portion of the suction tube material is cut so that the opening on the distal end side of the suction tube material that becomes the suction tube 1 becomes the inclined suction port 3a. Then, the suction tube material having the suction port 3a and the guide wire tube 2 are welded by a conventional method. Then, a cylindrical metal core material having a cross section in the shape of the edge 3b shown in FIG. 4A or 5 is inserted into the suction tube material through the suction port 3a of the welded body. Then, heat processing and cooling are performed at a temperature equal to or lower than the melting point of the suction tube material. Then, by pulling out the metal core material from the suction tube material, it is possible to obtain the suction catheter 10B including the suction tube 1 in which the curved portions 4a and 4b are formed on the edge 3b of the suction port 3a. For example, when manufacturing the suction catheter 10C shown in FIG. 5, a tubular member having an elliptical cross section is used as the metal core material.

[Summary]
A suction catheter 10 according to one embodiment of the present invention includes a suction tube 1 having a suction lumen A having a suction portion 3 at a distal end, and the suction portion 3 is inclined with respect to an axis X of the suction tube 1. A suction catheter 10 having a suction port 3a formed by the above, wherein in the suction portion 3, the most distal end position 1a on the most distal end side is the first position, and the most proximal end position 1b on the most proximal end side. Is the second position, the direction of the axis X is the first direction (longitudinal direction), and the direction of the line passing through the second position and perpendicular to the axis X is the second direction (vertical direction). The shape of the edge 3b forming the suction port 3a is the above-mentioned shape when viewed from the second position side in the second direction with a direction perpendicular to both the one direction and the second direction being the third direction (width direction). With respect to the first line (virtual line C) connecting the first position and the second position, It is a universal configuration.

  According to the above configuration, the shape of the edge 3b forming the suction port 3a is the first line (virtual line) when viewed from the second position (nearest end position 1b) side in the second direction (vertical direction). Since it is asymmetric with respect to C), the suction pressure distribution at the suction port 3a is disturbed. Therefore, the suction pressure distribution at the suction port 3a becomes asymmetrical with the first line as the axis of symmetry, and the most distal end position is based on the perpendicular D passing through the midpoint O of the first line (virtual line C). The suction pressure difference between the region on the 1a side and the region on the most proximal end position 1b side is small. Therefore, according to the above configuration, the suction pressure in the region on the first position side can be increased. As a result, according to the above configuration, as compared with the conventional suction catheter, the thrombus existing on the most distal end position 1a side is more easily sucked, and the suction performance for the thrombus caught on the guide wire is improved.

  Further, in the suction catheter 10 according to the embodiment of the present invention, when the two portions of the edge 3b that are divided based on the first line are a first edge 3c and a second edge 3d, the suction port 3a is The shape of the edge 3b forming the above may be a configuration in which the first edge 3c and the second edge 3d are at least partly non-overlapping when viewed from the third direction.

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

  Further, in the suction catheter 10B according to the embodiment of the present invention, the shape of the edge 3b forming the suction port 3a is such that the proximal end of the suction tube 1 is more than the first line when viewed from the third direction. It is preferably curved to the side.

  As a result, even if the suction catheter 10B has a small vertical dimension, the dimension of the suction port 3a capable of sucking the thrombus can be secured.

  In addition, in the suction catheter 10 according to the embodiment of the present invention, when the two parts of the edge divided based on the first line are a first edge 3c and a second edge 3d, the first edge 3c It is preferable that the length of is more than 1 time and not more than 3 times the length of the second edge 3d.

  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 of the suction port 3a can be increased.

  Further, in the suction catheter 10B according to the embodiment of the present invention, the shape of the edge 3b forming the suction port 3a when viewed from the distal end side in the first direction is the first line (phantom line C). A configuration in which a curved portion 4a that is asymmetrical as an axis of symmetry and that is curved outward from the peripheral edge 3b is arranged on the first position side with respect to a perpendicular D passing through the midpoint O of the first line. May be

  According to the above configuration, the shape of the edge 3b forming the suction port 3a is asymmetric with the first line as the axis of symmetry. Therefore, the suction pressure at the suction port 3a has an asymmetric distribution with the first line as the axis of symmetry. Therefore, at the suction port 3a, a difference in suction pressure occurs between the two areas A1 and A2 divided by the first line (imaginary line C).

  Furthermore, when the curved portion 4a that is curved outward is formed on the edge 3b, the suction pressure distribution at the suction port 3a is such that the suction pressure at the curved portion 4a is relatively high. According to the above configuration, since the curved portion 4a is arranged on the first position side (that is, the most distal end position 1a side) with respect to the perpendicular D, the curved portion 4a is located on the first position side with respect to the perpendicular D at the suction port 3a. The suction pressure in the area 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 suction pressure difference between the region on the first position side and the region on the second position side can be reduced.

  Further, in the suction catheter 10B according to the 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 midpoint O of the first line.

  Even with the above configuration, as compared with the conventional suction catheter, the thrombus is more likely to be sucked from the region of the suction port 3a on the most distal end position 1a side.

  Further, in the suction catheter 10B according to the embodiment of the present invention, the curved portion 4a is provided at least over the side wall 1c of the suction lumen A in a portion between the first position and the second position. May be

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

  Further, 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 elliptical when viewed from the distal end side in the direction of the axis X, and One of the vertices 4c and 4d (vertex 4c) in the long axis direction (direction of the long axis E) may be arranged on the first position side with respect to the perpendicular D.

  According to the above configuration, since the vertices 4c and 4d function as the above-mentioned curved portions, the suction pressure can be increased in the region closer to the most distal end position 1a than the perpendicular D.

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

1 suction tube 1a most distal position (first position)
1b Nearest end position (2nd 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 (First line)
D perpendicular X axis O midpoint

Claims (8)

A suction tube having a suction lumen having a suction portion at the distal end,
The suction section 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,
A direction of the axis is a first direction, a direction of a line passing through the second position and perpendicular to the axis is a second direction, and a direction perpendicular to both the first direction and the second direction is a third direction. As direction
Seen from the second position side in the second direction,
The suction catheter, wherein 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. When the two parts of the edge divided based on the first line are the first edge and the second edge,
The shape of the edge forming the suction port has at least a part where the first edge and the second edge do not overlap each other when viewed from the third direction. Suction catheter.   The shape of an edge forming the suction port is a shape curved toward the proximal end side of the suction tube with respect to the first line when viewed from the third direction. The suction catheter described. When the two parts of the edge divided based on the first line are the first edge and the second edge,
The suction catheter according to any one of claims 1 to 3, wherein the length of the first edge is more than 1 time and not more than 3 times the length of the second edge. When viewed from the distal end side in the first direction, the shape of the edge forming the suction port is
Is asymmetric about the first line as a symmetry axis, and
The curved portion curved outward from a peripheral edge is arranged on the first position side with reference to a perpendicular passing through the center of the first line. The suction catheter according to the item.   The suction catheter according to claim 5, wherein another curved portion is further arranged on the opposite side of the curved portion with respect to the center of the first line.   The suction catheter according to claim 5 or 6, wherein the curved portion is provided over at least a side wall of the suction lumen in a portion between the first position and the second position. Seen from the distal end side in the direction of the axis,
The shape of the edge forming the suction port is an elliptical shape, and 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 5 to 7.

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