Catheter device and method for collecting collection target object

Abstract

To provide a catheter device and the like capable of suppressing detachment of a collection target object.SOLUTION: A catheter device includes a retrieval portion provided on a first elongated body and having an opening expandable from a distal side toward a proximal side of the first elongated body, and a catheter having an occluding portion for closing the opening.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a catheter device and a method for retrieving an object to be retrieved. [Background technology]

[0002] Atherectomy devices are known for removing lesions such as plaque and thrombus from biological lumens such as blood vessels. When diseased tissue is removed using an atherectomy device, the removed material scatters within the blood vessel. If the removed material leaks to the peripheral side, it can cause occlusion of the peripheral blood vessel and potentially lead to the development of new lesions. Therefore, technologies have been proposed to capture the removed material within the blood vessel.

[0003] For example, Patent Document 1 discloses a sheath for retrieving a thrombus capture member, which has a lumen penetrating from the base end to the tip end and has a flexible tip tube with a reduced diameter at the tip end of the sheath or the tip opening of the tube. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-35923 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technology described in Patent Document 1 leaves room for improvement in terms of preventing the objects to be collected from falling off.

[0006] An object of one aspect of the present disclosure is to provide a catheter device or the like that can prevent a collection object from falling off. [Means for solving the problem]

[0007] (1) A catheter device according to one embodiment of the present disclosure includes a retrieval section provided on a first elongated body and having an opening expandable from the distal end side to the proximal end side of the first elongated body, and a catheter having a blocking section for blocking the opening.

[0008] (2) In the catheter device described in (1) above, the retrieval section may include a mesh body and a filter that covers the mesh of the mesh body.

[0009] (3) The catheter device described in (1) or (2) above may include a second elongated body that is inserted into the inner cavity of the first elongated body and is movable axially relative to the first elongated body, and the second elongated body has a storage section that stores the retrieval section before expansion, and the retrieval section may be detached from the storage section and the opening may be expanded by the second elongated body moving toward the tip side relative to the first elongated body.

[0010] (4) In the catheter device described in any one of (1) to (3) above, the first elongated body may be inserted into the inner cavity of the catheter, and the occlusion portion may block the opening by moving the first elongated body or the catheter along the axial direction of the first elongated body and the catheter in a direction that brings the recovery portion and the occlusion portion closer together.

[0011] (5) In the catheter device described in any one of (1) to (4) above, the occlusion portion may have a tapered shape expanding from the tip side toward the base side, and the outer diameter of the tip side of the occlusion portion may be smaller than the inner diameter of the retrieval portion, and the outer diameter of the base side of the occlusion portion may be larger than the inner diameter of the retrieval portion.

[0012] (6) In the catheter device according to any one of (1) to (5) above, the occlusion part may be a balloon that expands when supplied with an expansion fluid.

[0013] (7) In the catheter device described in any one of (1) to (6) above, the blocking portion may be a balloon that expands when an expansion fluid is supplied thereto, and the balloon may expand when the expansion fluid is supplied thereto while placed inside the collection portion, thereby expanding the opening, contract after expanding the opening, and expand again when the expansion fluid is supplied thereto after contracting, thereby blocking the opening of the collection portion from which the object to be collected has been collected.

[0014] (8) In the catheter device according to any one of (1) to (7) above, the occlusion section may have a connecting section that connects to the recovery section.

[0015] (9) A method for retrieving a retrieval object according to one embodiment of the present disclosure includes positioning a retrieval section provided on a first elongated body and having an opening expandable from the tip side to the base end side of the first elongated body distal to the retrieval object within a biological lumen, expanding the opening, retrieving the retrieval object using the retrieval section, and blocking the opening using a blocking section provided on a catheter. [Effects of the Invention]

[0016] According to the present disclosure, it is possible to prevent objects to be collected from falling off. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a diagram illustrating an example of the configuration of a catheter device according to an embodiment of the present invention. [Figure 2] FIG. 1 is a cross-sectional view of a catheter device. [Figure 3] FIG. 1 is an explanatory diagram illustrating an example of a method for collecting a collection target using a catheter device. [Figure 4] 10 is a flowchart illustrating an example of a method for collecting a collection target using a catheter device. [Figure 5] FIG. 10 is a diagram illustrating a configuration example of a catheter device according to a second embodiment. [Figure 6]FIG. 10 is an explanatory diagram illustrating an example of a method for collecting a collection target using the catheter device of the second embodiment. [Figure 7] FIG. 10 is a diagram illustrating a configuration example of a catheter device according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present disclosure will be specifically described with reference to the drawings showing embodiments thereof. Note that the dimensional proportions in the drawings are exaggerated for the convenience of explanation and may differ from the actual proportions.

[0019] (First embodiment) FIG. 1 is a diagram showing an example of the configuration of a catheter device 100 according to this embodiment. The catheter device 100 is a medical apparatus used in treatment to remove intravascular objects. The catheter device 100 is inserted into a blood vessel and used to remove and collect lesions (objects) such as thrombi, plaque, fibrin, coagulation, and fatty tissue. The catheter device 100 according to this embodiment is configured as a catheter device for PCI treatment used to remove lesions in coronary arteries. Note that the catheter device 100 can also be configured as a catheter device for removing lesions formed in other biological lumens, such as other blood vessels, bile ducts, tracheas, esophagus, other digestive tracts, urethras, and ear and nose cavities.

[0020] In the description of the embodiments, the direction in which the catheter device 100 extends is referred to as the axial direction, the side of the catheter device 100 that is inserted into a biological lumen in the axial direction is referred to as the "distal side," and the side that is operated proximal in the axial direction is referred to as the "proximal side." Furthermore, in the description of the embodiments, the distal end refers to a certain range including the distal end (the most distal end) and its periphery, and the proximal end refers to a certain range including the proximal end (the most proximal end) and its periphery.

[0021] The catheter device 100 comprises a long, tubular first catheter 1, a long, tubular second catheter 2, a long guidewire 3, and a long, tubular sheath 4. The first catheter 1 and the guidewire 3 are examples of an elongated body. The catheter device 100 is a catheter assembly.

[0022] The first catheter 1 comprises a first shaft 11 extending in the axial direction, a retrieval section 12 provided at the distal end of the first shaft 11, and a connector 13 provided at the proximal end of the first shaft 11. The first catheter 1 functions as a delivery catheter that carries the retrieval section 12. The first shaft 11 comprises an inner lumen 14 that extends axially from the distal end to the proximal end. The retrieval section 12 removes lesions (materials to be retrieved) such as thrombus, plaque, fibrin, coagulation, and fatty tissue from blood vessels, and retrieves the removed material.

[0023] In the assembled state of the catheter device 100, the first catheter 1 is inserted into the lumen 24 of the second catheter 2 so as to be axially movable relative to the second catheter 2. The axial length of the first catheter 1 is longer than the axial length of the second catheter 2. The central portion of the first catheter 1 is disposed in the lumen 24 of the second catheter 2, a portion of the distal end of the first catheter 1 including the retrieval section 12 is disposed so as to protrude toward the distal end of the second catheter 2, and a portion of the proximal end of the first catheter 1 including the connector 13 is disposed so as to protrude toward the proximal end of the second catheter 2. The relative positions of the first catheter 1 and the second catheter 2 can be changed as appropriate.

[0024] Examples of materials constituting the first shaft 11 include resin materials, metal materials, and combinations thereof. The resin materials are preferably soft resin materials. Examples of resin materials include polyolefins (e.g., polyethylene, polypropylene, polybutene, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, ionomers, and mixtures of two or more thereof), polystyrene, polyamide, polyester, polyurethane, polyimide, polyether ether ketone (PEEK), fluorine-based polymers (e.g., polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene copolymers (ETFE)), and mixtures thereof. Examples of metal materials include stainless steel, titanium, and titanium alloys.

[0025] A substantially cylindrical retrieval section 12 extending in the axial direction is provided so as to cover the outer peripheral surface of the first shaft 11. The retrieval section 12 has an opening 15 that is expandable in the radial direction from the distal end side to the proximal end side of the first shaft 11. In a contracted state, the retrieval section 12 is wound around the first shaft 11 in the circumferential direction. In a contracted state, the retrieval section 12 is housed in a housing section 32, which will be described later. When the retrieval section 12 is released from the housing section 32, it enters an expanded state in which it is expanded by its own elastic force (restoring force) in a natural state in which no external force is acting on it.

[0026] In the expanded state, the collection part 12 has a tapered shape in which the radial dimension gradually increases from the distal end to the proximal end. The space between the inner peripheral surface of the expanded collection part 12 and the outer peripheral surface of the first shaft 11 functions as a storage area for the object to be collected. The opening 15 of the collection part 12 refers to the above-mentioned space formed by the collection part 12.

[0027] The collection unit 12 includes an expandable mesh body 121 and a filter 122 that covers the mesh of the mesh body 121. The filter 122 is provided inside or outside the mesh body 121 so as to cover the entire mesh body 121. The filter 122 is superimposed on and fixed to the mesh body 121. The method for fixing the filter 122 is not particularly limited, but may be, for example, by adhesion or fusion. The tip of the mesh body 121 including the filter 122 is superimposed on and fixed to the outer circumferential surface of the first shaft 11 by adhesion or fusion. The mesh body 121 and the filter 122 may be integrated. The mesh body 121 expands inside the blood vessel and scrapes off the lesion that comes into contact with the mesh body 121. The scraped-off lesion is collected by the filter 122.

[0028] The material of the mesh body 121 is preferably a biocompatible metal, such as a shape memory alloy such as a nickel-titanium alloy or a cobalt-chromium alloy. The base end of each thread (wire 31) constituting the mesh body 121 may have a sharp tip.

[0029] The outer diameter of the opening 15 at the base end of the mesh body 121, i.e., the outer diameter of the opening 15 at the base end of the retrieval section 12, may be approximately the same as the inner diameter of the blood vessel into which the mesh body 121 is to be inserted. In this case, the mesh body 121 can make good contact with the narrowed portion of the blood vessel, thereby removing the diseased portion of the blood vessel.

[0030] The filter 122 is made of a material with many micropores. The filter 122 allows blood to pass through but traps the substances to be collected. The substances to be collected in the blood vessel are separated and collected by the filter 122. Examples of materials that can be used to make the filter 122 include resin materials, and specific examples include polyamide and polyester.

[0031] When filter 122 has approximately circular pores, the pore size of filter 122 is preferably 50 μm to 1000 μm, more preferably 50 μm to 500 μm, and even more preferably 100 μm to 200 μm, from the viewpoints of blood permeability and collection ability of the object to be collected.

[0032] The shape and configuration of the collection unit 12 are not limited to the above example, and any appropriate shape and configuration that is expandable and can collect the objects to be collected can be used. The shape of the collection unit 12 may be, for example, a cone shape, an umbrella shape, etc.

[0033] The connector 13 is generally cylindrical and sized to be easily manipulated by hand. The connector 13 functions as an operating section of the catheter device 100. By grasping and manipulating the connector 13, the surgeon can selectively move any one of the first catheter 1, the second catheter 2, and the guidewire 3, thereby changing their relative positions. The connector 13 can be made of the same material as the first shaft 11.

[0034] The second catheter 2 comprises a second shaft 21 extending in the axial direction, and an occlusion part 22 provided at the tip of the second shaft 21 for occluding the opening 15 of the collection part 12. The second catheter 2 functions as a delivery catheter for carrying the occlusion part 22. The second shaft 21 comprises an inner lumen 23 extending in the axial direction from the tip to the base end. Examples of materials constituting the second shaft 21 include the same materials as those of the first shaft 11.

[0035] An approximately cylindrical closure portion 22 extending in the axial direction is provided on the outer peripheral surface of the second shaft 21. Examples of materials constituting the closure portion 22 include the same materials as those of the first shaft 11. The closure portion 22 has a tapered shape in which the radial dimension gradually increases from the distal end side to the proximal end side. At least a portion of the closure portion 22 is inserted into the collection portion 12 from the proximal end opening and fixed at a specific position in the collection portion 12, thereby closing the opening 15. Note that the shape and configuration of the closure portion 22 are not limited to the above example, and any appropriate shape and configuration capable of closing the opening of the collection portion 12 can be used.

[0036] The outer diameter of the distal end of the occluding portion 22 is smaller than the inner diameter of the specific position in the collection portion 12, and the outer diameter of the proximal end of the occluding portion 22 is larger than the inner diameter of the specific position in the collection portion 12. The specific position in the collection portion 12 corresponds to the fixed position of the occluding portion 22. The fixed position of the occluding portion 22 is determined depending on the shapes and constituent materials of the occluding portion 22 and the collection portion 12, etc. The fixed position of the occluding portion 22 may be, for example, the proximal end of the collection portion 12, or may be a position closer to the distal end than the proximal end. In other words, the occluding portion 22 may be configured to block the opening 15 at the proximal end of the collection portion 12, or may be configured to block the opening 15 closer to the center than the proximal end of the collection portion 12.

[0037] The guide wire 3 includes a wire 31 extending in the axial direction, and a housing portion 32 provided at the distal end of the wire 31 for housing the recovery portion 12. Examples of materials that can be used to form the wire 31 include hard resins and metals (e.g., stainless steel, titanium, nickel-titanium alloys, etc.).

[0038] The storage section 32 has a storage area capable of storing the recovery section 12. The storage section 32 is generally cylindrical and extends in the axial direction. The tip of the storage section 32 is superimposed on and fixed to the outer circumferential surface of the wire 31 by adhesive bonding, fusion bonding, or the like. The space between the inner circumferential surface of the storage section 32 and the outer circumferential surface of the wire 31 forms the storage area. Examples of materials constituting the storage section 32 include the same materials as those of the first shaft 11.

[0039] In the assembled state of the catheter device 100, the guidewire 3 is inserted into the lumen 14 of the first catheter 1 so as to be movable in the axial direction relative to the first catheter 1. The axial length of the guidewire 3 is longer than the axial length of the first catheter 1. The central portion of the guidewire 3 is disposed in the lumen 14 of the first catheter 1, a portion of the distal end of the guidewire 3 including the housing portion 32 is disposed so as to protrude toward the distal end of the first catheter 1, and a portion of the proximal end of the guidewire 3 is disposed so as to protrude toward the distal end of the first catheter 1. The relative positions of the guidewire 3 and the first catheter 1 can be changed as appropriate.

[0040] In this embodiment, a guidewire 3 is used as the elongated body, but the elongated body may be any elongated body that can be inserted into the first catheter 1. The elongated body may be a tubular member having a lumen (for example, a catheter).

[0041] The sheath 4 is a guiding catheter that guides the guidewire 3, the first catheter 1, and the second catheter 2, and includes a third shaft 41 extending in the axial direction and a hub 42 provided at the proximal end of the third shaft 41. The third shaft 41 includes an inner lumen 43 that extends in the axial direction from the distal end to the proximal end. Materials that can be used to construct the third shaft 41 and the hub 42 include the same materials as those used for the first shaft 11.

[0042] Figure 2 is a cross-sectional view of the catheter device 100. Figure 2 shows a cross-section of the catheter device 100 taken along line II-II in Figure 1 in an assembled state. In the assembled state of the catheter device 100, the first catheter 1 is inserted into the lumen 23 of the second shaft 21 of the second catheter 2, and the guidewire 3 is inserted into the lumen 14 of the first shaft 11 of the first catheter 1. The second catheter 2, first catheter 1, and guidewire 3 assembled as described above are inserted into the lumen 43 of the third shaft 41 of the sheath 4.

[0043] Fig. 3 is an explanatory diagram illustrating an example of a method for collecting a collection target using the catheter device 100. Fig. 4 is a flowchart showing an example of a method for collecting a collection target using the catheter device 100. A method for using the catheter device 100 of this embodiment and a method for collecting a collection target using the catheter device 100 will be described with reference to Figs. 3 and 4.

[0044] 3, in the initial assembled state of the catheter device 100, the unexpanded retrieval portion 12 is housed in the housing portion 32, and the housing portion 32 and the retrieval portion 12 are located distal to the occlusion portion 22. A certain distance is maintained between the retrieval portion 12 and the occlusion portion 22. The retrieval portion 12 may be housed entirely within the housing portion 32, or only a portion of the retrieval portion 12 may be housed within the housing portion 32.

[0045] First, the surgeon percutaneously inserts the sheath 4 into the blood vessel 5 (step S1). Next, the surgeon inserts the assembled guide wire 3, first catheter 1, and second catheter 2 into the blood vessel 5 through the sheath 4 (step S2).

[0046] While maintaining the above-described positional relationship, the surgeon advances the guidewire 3, the first catheter 1, and the second catheter 2 until the storage portion 32 and the retrieval portion 12 reach the target site distal to the lesion (e.g., thrombus) 6, which is the object to be retrieved. As a result, the storage portion 32 and the retrieval portion 12 are positioned distal to the lesion 6, as shown in the topmost part of Figure 3. At this time, the occlusion portion 22 is positioned proximal to the lesion 6.

[0047] Once the storage portion 32 and the retrieval portion 12 are positioned distal to the lesion 6, the surgeon detaches the retrieval portion 12 from the storage portion 32 to expand the opening 15 of the retrieval portion 12 (step S3). Specifically, while the first catheter 1 and the second catheter 2 are fixed, the guidewire 3 is moved toward the distal end (distal side). That is, while maintaining the positional relationship between the retrieval portion 12 and the occlusion portion 22, the storage portion 32 is moved toward the distal end. As the guidewire 3 moves toward the distal end relative to the first catheter 1, the retrieval portion 12 is detached from the storage portion 32. As a result, as shown in the second from the top of Figure 3, the mesh body 121 of the retrieval portion 12 expands due to its own restoring force, and the opening 15 expands toward the proximal end.

[0048] After the retrieval portion 12 is expanded, the surgeon moves the retrieval portion 12 from the distal side to the proximal side of the lesion 6 while fixing the guide wire 3 and the second catheter 2, thereby removing and retrieving the lesion 6 (step S4). As shown in the third illustration from the top in Figure 3, when the first catheter 1 is pulled out, the lesion 6 in the blood vessel 5 is scraped off and removed by the mesh body 121 of the retrieval portion 12, and is also collected by the filter 122 and retrieved within the retrieval portion 12. The surgeon may move the first catheter 1 from the distal side to the proximal side while rotating it radially.

[0049] After removing the lesion 6, the surgeon moves the first catheter 1 or the second catheter 2 in a direction that brings the retrieval site 12 and the occlusion site 22 closer to each other, thereby blocking the opening 15 of the retrieval site 12 (step S5). Specifically, while the guidewire 3 and the second catheter 2 are fixed, the first catheter 1 is moved toward the base end (proximal side). That is, while the positions of the storage site 32 and the occlusion site 22 are fixed, the retrieval site 12 is moved toward the proximal side. As the first catheter 1 moves toward the base end relative to the second catheter 2, the retrieval site 12 moves to the position of the occlusion site 22, and at least a portion of the occlusion site 22 is inserted into the retrieval site 12. As a result, as shown in the fourth position from the top in Figure 3, the occlusion site 22 is fixed at a specific position within the retrieval site 12, blocking the opening 15 of the retrieval site 12.

[0050] In adjusting the relative positions of the first catheter 1 and the second catheter 2, the surgeon may move the second catheter 2 distally while fixing the guidewire 3 and the first catheter 1. That is, the occlusion part 22 may be moved distally while fixing the positions of the storage part 32 and the retrieval part 12. For example, by moving the first catheter 1 toward the proximal end and then further moving the second catheter 2 distally, the retrieval part 12 can be moved smoothly without resisting the blood flow, and the occlusion part 22 can be more reliably fitted into the retrieval part 12.

[0051] After closing the retrieval part 12, the surgeon removes the guide wire 3, the first catheter 1, and the second catheter 2 from the blood vessel 5 via the sheath 4 (step S6). The retrieval part 12 containing the retrieval object is retrieved from the blood vessel 5.

[0052] According to this embodiment, the retrieval unit 12 can be blocked by the blocking unit 22, which prevents the object from falling out. The retrieval unit 12 allows the removal and retrieval of the lesion at the same time, which leads to a reduction in the procedure time and a simplification of the procedure.

[0053] By configuring the catheter device 100 to have a multi-layer structure, it is possible to easily adjust the relative positions of each component to expand or close the retrieval site 12. By making the occlusion site 22 function as a lid for the retrieval site 12, the opening of the retrieval site 12 can be reliably closed.

[0054] In particular, in PCI treatment or coronary artery lesion removal, suction of the removed object is difficult due to the shape, properties, hardness, quantity, etc. of the object. Furthermore, cardiac thrombi are smaller in size than cerebral or venous thrombi, and are presumed to often consist of multiple independent objects rather than a mass. According to this embodiment, even when a large number of small objects to be collected are present, by blocking the collection portion 12, the objects collected in the collection portion 12 can be prevented from flowing out again into the blood vessel due to the influence of blood flow, and in particular, the outflow of the objects to be collected to the peripheral side can be suppressed.

[0055] (Second embodiment) The catheter device 100 of the second embodiment includes an expandable / contractable occlusion section 22. In the following embodiment, differences from the first embodiment will be mainly described, and components common to the first embodiment will be assigned the same reference numerals and detailed description thereof will be omitted.

[0056] 5 is a diagram showing an example of the configuration of a catheter device 100 of the second embodiment. The catheter device 100 of the second embodiment includes a second catheter 2, a guidewire 3, and a sheath 4, but does not include a first catheter 1. The recovery section 12 of the second embodiment is provided at the tip of the guidewire 3, instead of the first catheter 1 of the first embodiment. Furthermore, the guidewire 3 does not include a storage section 32.

[0057] The second catheter 2 includes a second shaft 21 and a balloon 22a serving as an occlusion section 22 configured to be radially expandable and contractible. The balloon 22a is substantially cylindrical in an expanded state. The balloon 22a expands when an expansion fluid is supplied to the interior thereof, and contracts when the expansion fluid is discharged from the interior thereof. The expansion fluid that expands the balloon 22a may be a liquid (e.g., saline, contrast agent, etc.) or a gas (e.g., helium gas, CO2 gas, O2 gas, etc.), and is preferably saline.

[0058] The second shaft 21 includes an outer shaft 21a having a lumen 23a extending along the axial direction, and an inner shaft 21b disposed in the lumen 23a of the outer shaft 21a and having a lumen 23b extending along the axial direction. The distal end of the inner shaft 21b protrudes toward the distal end of the outer shaft 21a. The lumen 23a of the outer shaft 21a is a fluid supply lumen for circulating an inflation fluid. The lumen 23b of the inner shaft 21b is a guidewire lumen through which a guidewire 3 is inserted. In the assembled state of the catheter device 100, the guidewire 3 is inserted through the lumen 23b so as to be axially movable relative to the second catheter 2.

[0059] The outer shaft 21a has a distal opening formed on its distal end surface that communicates with the lumen 23a, and a proximal opening formed on its proximal end surface that also communicates with the lumen 23a. The distal opening communicates with the internal space of the balloon 22a. The proximal opening communicates with an inflation fluid supply unit (not shown).

[0060] The balloon 22a has a tapered portion provided on the distal end side, which has a tapered shape with a radial dimension gradually increasing from the distal end side to the proximal end side, and a reverse tapered portion provided on the proximal end side, which has a reverse tapered shape with a radial dimension gradually decreasing from the distal end side to the proximal end side. The distal end of the balloon 22a is superimposed on and fixed to the outer peripheral surface of the distal end of the inner shaft 21b by, for example, adhesive bonding or fusion bonding. The proximal end of the balloon 22a is fixed to the outer peripheral surface of the outer shaft 21a by, for example, adhesive bonding or fusion bonding.

[0061] The balloon 22a is made of a flexible membrane material that allows expansion and contraction. Examples of materials that can be used to form the balloon 22a include resin materials. Examples of resin materials include polyolefins (e.g., polyethylene, polypropylene, polybutene, ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, ionomers, and mixtures of two or more of these), polystyrene, polyamide, polyester, polyurethane, polyimide, polyether ether ketone (PEEK), fluorine-based polymers (e.g., polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene copolymers (ETFE)), and mixtures of these.

[0062] The outer diameter of the distal end of the balloon 22a in the expanded state is smaller than the inner diameter at the specific position in the retrieval site 12, and the maximum outer diameter of the balloon 22a in the expanded state is larger than the inner diameter at the specific position in the retrieval site 12.

[0063] In the above example, the guidewire 3 is configured to have the retrieval portion 12, but similar to the first embodiment, the retrieval portion 12 may be configured to be provided on the first catheter 1. When the first catheter 1 is provided with the retrieval portion 12, a guidewire 3 that does not have a storage portion 32 may be inserted into the first catheter 1.

[0064] FIG. 6 is an explanatory diagram illustrating an example of a method for collecting a collection target using the catheter device 100 of the second embodiment.

[0065] 6, in the initial state of the catheter device 100 of the second embodiment, the retrieval portion 12 is folded along the outer surface of the guidewire 3. The balloon 22a is housed in a folded, unexpanded state inside the folded retrieval portion 12. The balloon 22a may be housed entirely within the retrieval portion 12, or only a portion of it may be housed within the retrieval portion 12.

[0066] While maintaining the above-described positional relationship, the surgeon inserts and advances the guide wire 3 and the second catheter 2 into the blood vessel 5 via the sheath 4. As shown in the topmost part of Figure 6, the surgeon brings the retrieval portion 12 and the balloon 22a to the target site distal to the lesion 6.

[0067] After positioning the retrieval portion 12 and the balloon 22a distal to the lesion 6, the surgeon supplies an expansion fluid to the balloon 22a to expand the balloon 22a while fixing the guide wire 3 and the second catheter 2. As a result, as shown in the second from the top in Figure 6, the retrieval portion 12 expands with plastic deformation due to the expansion force of the balloon 22a, and the opening 15 expands toward the base end.

[0068] After expanding the retrieval site 12, the surgeon discharges the expansion fluid from the balloon 22a to deflate the balloon 22a. After deflating the balloon 22a, the surgeon moves the second catheter 2 toward the base end (proximal side) while keeping the guidewire 3 fixed. That is, while keeping the position of the retrieval site 12 fixed, the surgeon moves the balloon 22a toward the proximal side. As a result, the retrieval site 12 is positioned distal to the lesion site 6, and the balloon 22a is positioned proximal to the lesion site 6, as shown in the third figure from the top in Figure 6.

[0069] Thereafter, as shown in the fourth figure from the top, while the second catheter 2 is fixed, the retrieval part 12 is moved from the distal side to the proximal side of the lesion 6 to remove and retrieve the lesion 6.

[0070] After removing the lesion 6, the surgeon moves the first catheter 1 or the second catheter 2 in a direction that brings the retrieval site 12 and the balloon 22a closer to each other, thereby closing the opening 15 of the retrieval site 12. Specifically, while the second catheter 2 is fixed, the guidewire 3 is moved toward the base end (proximal side). That is, while the position of the balloon 22a is fixed, the retrieval site 12 is moved toward the proximal side. As the guidewire 3 moves toward the base end relative to the second catheter 2, the retrieval site 12 moves to the position of the balloon 22a. The surgeon may move the guidewire 3 to a position where at least a portion of the base end side of the retrieval site 12 and at least a portion of the tip end side of the balloon 22a overlap in the axial direction. Alternatively, the surgeon may move the second catheter 2 toward the distal side while the guidewire 3 is fixed.

[0071] Thereafter, the surgeon supplies inflation fluid to the balloon 22a to inflate the balloon 22a again while maintaining the positional relationship between the guide wire 3 and the second catheter 2. As a result, the inflated balloon 22a closes the opening 15 of the recovery site 12, as shown in the fifth figure from the top in Figure 6.

[0072] After closing the retrieval site 12 , the surgeon removes the guide wire 3 and the second catheter 2 from the blood vessel 5 via the sheath 4 .

[0073] According to this embodiment, the retrieval portion 12 can be expanded and occluded by the expandable / contractable occlusion portion 22, thereby improving the design freedom of the catheter device 100. There is no need to provide a storage portion 32, which simplifies the configuration of the catheter device 100. By providing the retrieval portion 12 on the guidewire 3, the first catheter 1 is no longer necessary, further simplifying the configuration of the catheter device 100.

[0074] (Third embodiment) The catheter device 100 of the third embodiment connects the occlusion section 22 and the recovery section 12 via a connecting section 26. In the following embodiment, differences from the first embodiment will be mainly described, and components common to the first embodiment will be assigned the same reference numerals and detailed description thereof will be omitted.

[0075] 7 is a diagram showing an example of the configuration of a catheter device 100 according to a third embodiment. The catheter device 100 according to the third embodiment includes a first catheter 1, a second catheter 2, a guidewire 3, and a sheath 4, similar to the first embodiment.

[0076] The occlusion section 22 of the second catheter 2 includes a tapered section 22b provided on the distal end side and having a tapered shape whose radial dimension gradually increases from the distal end side to the proximal end side, and a reverse tapered section 22c provided on the proximal end side of the tapered section 22b and having a reverse tapered shape whose radial dimension gradually decreases from the distal end side to the proximal end side. The occlusion section 22 of the third embodiment is configured to be radially contractible, for example, by configuring the tapered section 22b and the reverse tapered section 22c from a flexible material.

[0077] A plurality of connecting portions 26 for connecting to the collection portion 12 are provided on the outer peripheral surface of the tapered portion 22b. The connecting portions 26 are, for example, claw-shaped, and connect the blocking portion 22 and the collection portion 12 by hooking the claw portions onto the mesh body 121 of the collection portion 12. While FIG. 6 shows an example in which two connecting portions 26 are provided, the number of connecting portions 26 may be three or more. The plurality of connecting portions 26 may be provided at equal intervals in the circumferential direction on the outer peripheral surface of the tapered portion 22b.

[0078] In the catheter device 100 of the third embodiment, after the lesion is removed by the retrieval unit 12 in the same manner as in the first embodiment, the occlusion unit 22 occludes the opening 15 of the retrieval unit 12. At this time, the tapered portion 22b of the occlusion unit 22 is inserted into the retrieval unit 12, whereby the connecting portion 26 engages with the mesh body 121 of the retrieval unit 12, connecting the retrieval unit 12 and the occlusion unit 22. When the first catheter 1 and the second catheter 2 are removed toward the proximal end with the connecting portion 26 connected to the retrieval unit 12, the reverse tapered portion 22c of the occlusion unit 22 contracts radially due to the pressure of the blood flow on the reverse tapered portion 22c. In response to the contraction of the reverse tapered portion 22c, the tapered portion 22b contracts radially, and the mesh body 121 connected to the tapered portion 22b also contracts radially. Note that the method for expanding and contracting the occlusion unit 22 is not limited to the above example and may be performed, for example, by supplying and discharging an inflation fluid to and from the inside of the occlusion unit 22.

[0079] According to this embodiment, the retrieval target can be retrieved from inside the blood vessel by contracting the retrieval section 12 that contains the retrieval target. The opening diameter of the retrieval section 12 is increased to ensure contact with the lesion in the blood vessel, and the catheter device 100 can be smoothly retrieved by contracting the retrieval section 12 after removal. By connecting the retrieval section 12 and the occlusion section 22 with the connecting section 26, it is possible to prevent a gap from occurring between the occlusion section 22 and the retrieval section 12, even when the retrieval section 12 is contracted, and to prevent the retrieval target from falling off.

[0080] The catheter device and the method for retrieving a retrieval object may be applied to humans or animals other than humans. The catheter device and the method for retrieving a retrieval object may also be applied to a living body model for practicing procedures.

[0081] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The technical features described in each embodiment can be combined with each other, and the scope of the present invention is intended to include all modifications within the scope of the claims and the scope equivalent to the claims. The sequences shown in each embodiment are not limited, and the order of each process may be changed within a range consistent with the present invention, and multiple processes may be executed in parallel. The entity that performs each process is not limited, and the process of each device may be executed by another device within a range consistent with the present invention.

[0082] The matters described in each embodiment can be combined with each other. In addition, the independent claims and dependent claims described in the claims can be combined with each other in any combination, regardless of the reference format. Furthermore, although the claims use a format in which a claim references two or more other claims (multiple claim format), this is not limited to this format. A multiple claim (multi-multi claim) that references at least one other multiple claim may also be used. [Explanation of symbols]

[0083] 100 Catheter Device 1. First catheter 11 First Shaft 12 Collection Department 121 Net body 122 filters 13 Connectors 14 lumen 15 Aperture 2. Second catheter 21 Second shaft 22 Occlusion 22a Balloon 23 lumen 26 Connecting part 3 Guidewire 31 Wire rod 32 Storage section 4 Sheath

Claims

1. a collection section provided on the first elongated body and having an opening expandable from a distal end side to a proximal end side of the first elongated body; a catheter having a blocking portion for blocking the opening; Catheter device.

2. The recovery unit includes: A mesh body and a filter that covers the mesh of the mesh body; The catheter device of claim 1 .

3. a second elongated body inserted into an inner cavity of the first elongated body so as to be movable in an axial direction relative to the first elongated body; the second elongated body has a housing portion that houses the collection portion before expansion, When the second elongated body moves toward the distal end side relative to the first elongated body, the recovery portion is separated from the storage portion, and the opening is expanded. A catheter device according to claim 1 or claim 2.

4. the first elongated body is inserted into the lumen of the catheter, The first elongated body or the catheter moves along the axial direction of the first elongated body and the catheter in a direction in which the collection section and the blocking section approach each other, whereby the blocking section blocks the opening. A catheter device according to claim 1 or claim 2.

5. The occlusion portion has a tapered shape expanding from the distal end side toward the proximal end side, The outer diameter of the distal end of the occluding portion is smaller than the inner diameter of the retrieval portion, and the outer diameter of the proximal end of the occluding portion is larger than the inner diameter of the retrieval portion. A catheter device according to claim 1 or claim 2.

6. The occlusion part is a balloon that expands when an expansion fluid is supplied. A catheter device according to claim 1 or claim 2.

7. the occlusion portion is a balloon that expands when an expansion fluid is supplied, The balloon is The expansion fluid is supplied to the collection section while the collection section is disposed therein, thereby expanding the opening. The opening is expanded and then contracted, After contraction, the expansion fluid is supplied to expand the collection section, and the collection section collects the object to be collected, thereby closing the opening. A catheter device according to claim 1 or claim 2.

8. The closure portion has a connecting portion that connects to the collection portion. A catheter device according to claim 1 or claim 2.

9. a retrieval section provided on the first elongated body and having an opening expandable from a distal end side to a proximal end side of the first elongated body, the retrieval section being disposed distal to the retrieval target within the biological lumen; Expanding the opening; The recovery unit recovers the recovery target, The opening is closed by a closing portion provided on the catheter. How the items to be collected will be collected.

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