snare

Abstract

The utility model relates to a kind of trappers, including fixed capture ring and movable capture ring;When being in first state, the projection of fixed capture ring and movable capture ring on the same preset axial plane has first annular contour and second annular contour respectively, preset axial plane is parallel with the width direction of the movable capture ring, first annular contour and second annular contour exist intersection point, in the region of intersection point distal side, first annular contour is located in second annular contour, in the region of intersection point proximal side, the projection of capture wire connected with control wire in movable capture ring is located in first annular contour. The trapper of the embodiment can efficiently and firmly capture electrode lead.

Description

Technical Field

[0001] This utility model relates to the field of medical devices, and in particular to a capture device. Background Technology

[0002] With the increasing number of implanted cardiac medical devices such as pacemakers, implantable cardioverter defibrillators, and cardiac resynchronization therapy, related complications such as lead breakage and lead wear are also increasing year by year, leading to a rapid increase in the demand for lead retrieval. Currently, there are two main methods for lead retrieval: The first is to remove the lead through open-chest surgery, which has disadvantages such as high surgical costs and significant trauma. The second is intravenous interventional lead retrieval. Under angiographic conditions, a capture device is delivered intravenously to the lead location, then the capture device captures and loads the lead to be retrieved. Finally, the lead is withdrawn from the body along with the capture device, completing the lead retrieval. While this method has advantages such as low cost and minimal trauma, the continuous heartbeat during the procedure often causes the lead to move with the heartbeat, making it difficult for the capture device to efficiently and securely capture the lead. Utility Model Content

[0003] Based on this, the present invention provides a capture device that can efficiently and firmly capture electrode wires.

[0004] This utility model provides a capture device for capturing target objects within a living organism, comprising:

[0005] The capturing unit includes a fixed capturing ring and a movable capturing ring; in a first state, the distal ends of the fixed capturing ring and the movable capturing ring are separated radially, forming a capturing space with an opening at the distal end; in a second state, the fixed capturing ring and the movable capturing ring are radially close to each other, and the annular structure of the movable capturing ring is sleeved on the outside of the fixed capturing ring.

[0006] A control unit, connected to the capture unit, is used to control the fixed capture ring and the movable capture ring to switch between the first state and the second state. The control unit includes a pusher and a control wire connected to the capture unit.

[0007] The movable capture ring includes two capture wires, which are arranged along the width of the movable capture ring and connected at the far apex of the movable capture ring. The proximal end of at least one capture wire is connected to the control wire, which is used to drive the capture wire connected to it to move so that the movable capture ring expands or contracts.

[0008] When in the first state, the projections of the fixed capture ring and the movable capture ring on the same preset axial plane have a first annular profile and a second annular profile, respectively. The preset axial plane is parallel to the width direction of the movable capture ring. The first annular profile and the second annular profile intersect at a point. In the region on the far side of the intersection point, the first annular profile is located within the second annular profile. In the region on the near side of the intersection point, the projection of the capture wire connected to the control wire in the movable capture ring is located within the first annular profile.

[0009] In one embodiment, when in the first state, the active capture ring has a teardrop-shaped or teardrop-like profile, and the fixed capture ring has an olive-shaped or petal-shaped profile with pointed ends along the axis, and the curvature at the distal vertex of the active capture ring is less than the curvature at the distal vertex of the fixed capture ring.

[0010] In one embodiment, when in the first state, the fixed capture ring has a first segment, one endpoint of which is the far vertex of the fixed capture ring, and the other endpoint of which is located between the maximum width of the fixed capture ring and the far vertex of the fixed capture ring. The first segment has a first rate of curvature change. The movable capture ring has a second segment, one endpoint of which is the far vertex of the movable capture ring, and the other endpoint of which is located between the maximum width of the movable capture ring and the far vertex of the movable capture ring. The second segment has a second rate of curvature change, and the absolute value of the first rate of curvature change is greater than the absolute value of the second rate of curvature change.

[0011] In one embodiment, when in the first state, the minimum axial distance between the maximum width of the active capture ring and the far vertex of the active capture ring is a first distance, and the first ratio of the first distance to the axial length of the active capture ring is less than 0.5.

[0012] In one embodiment, the projection of the maximum width of the active capture ring is located on the far side of the intersection, and the first ratio ranges from 0.1 to 0.4.

[0013] In one embodiment, when in the first state, the minimum axial distance between the maximum width of the fixed capture ring and the far vertex of the fixed capture ring is the second distance, and the second ratio of the second distance to the axial length of the fixed capture ring is in the range of 0.3 to 0.8.

[0014] In one embodiment, when in the first state, the maximum outward deviation of the movable capture ring is less than the maximum outward deviation of the fixed capture ring. The maximum outward deviation of the movable capture ring is less than the maximum outward deviation of the fixed capture ring when the fixed capture ring, the movable capture ring, and the distal end of the pusher are projected onto the same radial plane. The maximum radial distance between the projection of the movable capture ring and the projection of the distal end of the pusher is less than the maximum radial distance between the projection of the fixed capture ring and the projection of the distal end of the pusher.

[0015] In one embodiment, when in the first state, the fixed capture ring has a curved structure that is concave outwards, and the movable capture ring is approximately located on the same plane. The movable capture ring being approximately located on the same plane means that there is a plane a, and the deviation of the movable capture ring from the plane a does not exceed 2 mm.

[0016] In one embodiment, after being in the second state, the movable capture ring can retract to cooperate with the fixed capture ring to form a locking space that can limit the distal end, so that the capture part changes from the second state to the third state. When in the third state, the distal end of the fixed capture ring is axially further away from the proximal end of the capture part than the distal end of the movable capture ring.

[0017] In one embodiment, the catcher includes two fixed catching rings and one movable catching ring, wherein the two fixed catching rings are a first fixed catching ring and a second fixed catching ring; when in the first state, the distal ends of the first fixed catching ring and the distal ends of the second fixed catching ring are respectively located on both sides of the movable catching ring; when in the second state, the first fixed catching ring and the second fixed catching ring are radially close to each other and interweave to form a cross configuration.

[0018] In one embodiment, when the first fixed capture ring and the second fixed capture ring are in an intersecting configuration, the first fixed capture ring and the second fixed capture ring respectively include a first overhang segment and a second overhang segment on the distal side of their intersecting area, extending from the proximal end to the distal end, with the first overhang segment and the second overhang segment extending in a direction away from each other; the movable capture ring can retract to allow the distal end of the movable capture ring to enter between the first overhang segment and the second overhang segment, so as to cooperate with the first fixed capture ring and the second fixed capture ring to form a locking space.

[0019] In one embodiment, the catcher further includes a conduit having a first inner cavity extending axially; a pusher having a second inner cavity extending axially, the control wire passing through the second inner cavity and movable axially relative to the pusher; the pusher passing through the first inner cavity and movable axially relative to the conduit, the distal end of the pusher being connected to the catching part to drive the catching part to move axially relative to the conduit, so that the catching part can be completely contained within the conduit or released from the conduit to form a first state; when the catching part in the first state moves proximally relative to the conduit and is partially compressed within the conduit, it switches to the second state; the proximal end of the fixed catching ring is fixedly connected to the pusher, one end of the catching wire of the movable catching ring is fixedly connected to the pusher, and the other end of the catching wire is fixedly connected to the control wire.

[0020] The capture device of this utility model includes a capture part and a control part. The capture part includes a fixed capture ring and a movable capture ring. In a first state, the distal ends of the fixed capture ring and the movable capture ring are separated radially, forming a capture space with an opening at the distal end. In a second state, the fixed capture ring and the movable capture ring are radially close to each other, and the annular structure of the movable capture ring is sleeved on the outside of the fixed capture ring. The control part is connected to the capture part and is used to control the switching of the fixed capture ring and the movable capture ring between the first state and the second state. The control part includes a pusher and a control wire connected to the capture part. The movable capture ring includes two capture wires, which are arranged along the width direction of the movable capture ring. At the distal apex of the movable capture ring, at least one segment of the capture wire is connected to the proximal end of the control wire. The control wire drives the connected capture wire to move, causing the movable capture ring to expand or contract. In the first state, the projections of the fixed capture ring and the movable capture ring onto a preset axial plane have a first annular profile and a second annular profile, respectively. The preset axial plane is parallel to the width direction of the movable capture ring. The first and second annular profiles intersect at a point. In the region on the distal side of the intersection point, the first annular profile is located within the second annular profile. In the region on the proximal side of the intersection point, the projection of the capture wire connected to the control wire in the movable capture ring is located within the first annular profile. This configuration reduces the resistance to the control wire driving the connected capture wire, allowing for more flexible and efficient control of the movable capture ring's expansion or contraction. Furthermore, the larger internal space in the distal region of the movable capture ring improves the success rate of transitioning from the fixed to the movable capture ring to the second state. Because the fixed and movable capture rings of the capture device have a second state, they can confine the target object within the capture space between them. The size of this capture space is adjustable; by reducing the size of the capture space, the fixed and movable capture rings can exert a clamping force on the target object, thus firmly restraining it within them and achieving secure capture. Furthermore, in the second state, the movable capture ring is reduced by a control wire, causing the fixed and movable capture rings to work together to lock the target object, preventing it from escaping. Therefore, the capture device of this embodiment can efficiently and securely capture electrode wires, significantly reducing surgical time and improving the success rate of the procedure. Attached Figure Description

[0021] Figure 1 This is a three-dimensional structural diagram of the catcher in its first state according to an embodiment of the present invention;

[0022] Figure 2a This is a schematic diagram showing the shapes of the fixed capture ring and the movable capture ring in the first state of the capture device in one embodiment of the present invention;

[0023] Figure 2b for Figure 2a A schematic diagram showing the projection of the fixed capture ring and the movable capture ring on the same preset axial plane;

[0024] Figure 3 This is a side view of the catcher in a first state according to an embodiment of the present invention;

[0025] Figure 4 This is a top view of the catcher in its first state according to an embodiment of the present invention, from the distal end toward the proximal end.

[0026] Figure 5 This is a side view of the catcher in a first state according to another embodiment of the present invention;

[0027] Figure 6 for Figure 5 A top view of the capture device in its first state, from the far end towards the near end;

[0028] Figure 7 This is a schematic diagram showing the shapes of the fixed capture ring and the movable capture ring in the first state of the capture device in another embodiment of the present invention;

[0029] Figure 8 for Figure 7 A side view diagram of the capture device;

[0030] Figure 9 for Figure 7 A three-dimensional structural diagram of the capture device;

[0031] Figure 10 for Figure 7 A side view of the capture device in its second state;

[0032] Figure 11 for Figure 7 A three-dimensional structural diagram of the capture device in its second state;

[0033] Figure 12 for Figure 10 A side view of the capture ring of the capture device further contracting;

[0034] Figure 13 for Figure 10 A three-dimensional structural diagram of the further contraction of the moving capture ring of the capture device;

[0035] Figure 14 for Figure 13 A three-dimensional structural diagram of the further contraction of the moving capture ring of the capture device;

[0036] Figure 15This is a schematic diagram of the catcher capturing a target object and being in a first state according to one embodiment of the present invention;

[0037] Figure 16 This is a schematic diagram of the catcher capturing a target object and being in a second state in one embodiment of the present invention;

[0038] Figure 17 This is a schematic diagram of the capture device forming a locking space to lock the target object in one embodiment of the present invention. Detailed Implementation

[0039] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0040] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0042] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0043] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0044] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0045] It should be noted that in the field of interventional medical devices, the end of a medical device implanted in the human or animal body that is closer to the operator is generally called the "proximal end," and the end that is farther from the operator is called the "distal end." Based on this principle, the "proximal end" and "distal end" of any component of a medical device are defined. "Axial direction" generally refers to the length direction of the medical device during delivery, and "radial direction" generally refers to the direction of the medical device perpendicular to its "axial direction." Based on this principle, the "axial direction" and "radial direction" of any component of a medical device are defined.

[0046] Example 1

[0047] Please refer to Figure 1 , Figure 2a This embodiment provides a capture device 100, which can be used to remove elongated target objects, such as wires or guide wires, from a living organism. For ease of understanding, this embodiment uses a wire from a cardiac implantable medical device as an example of the target object.

[0048] The capture device 100 in this embodiment includes a capture unit 20 and a control unit 30.

[0049] The capture unit 20 is used to capture target objects within a living organism. The control unit 30 includes a pusher 31 and a control wire 32. The distal end of the pusher 31 is connected to the capture unit 20 and is used to push the capture unit 20. The control wire 32 is connected to the capture unit 20 and is used to change the shape of the capture unit 20.

[0050] The capturing unit 20 has radial expansion capability, allowing it to radially contract under external force, and to self-expand or mechanically expand back to its naturally unfolded shape (also known as a fully unfolded shape) and maintain this shape after the external force is removed. Referring also to Figure 2, the capturing unit 20 includes a fixed capturing ring 21 and a movable capturing ring 22. The distal ends of both the fixed capturing ring 21 and the movable capturing ring 22 are free ends, allowing relative movement between the distal ends of the fixed capturing ring 21 and the movable capturing ring 22.

[0051] The fixed capture ring 21 and the movable capture ring 22 have a first state and a second state that can be switched between each other. Figure 2. Figure 3 The first state of the fixed capture ring 21 and the movable capture ring 22 is shown. In the first state, the distal ends of the fixed capture ring 21 and the movable capture ring 22 are radially spaced apart and separated from each other. For example, the capture part 20 has at least one axial plane (i.e., a plane parallel to the central axis; in this invention, the virtual central axis of the pusher 31 is used as the central axis of the capture part 20). In the distal section, the fixed capture ring 21 and the movable capture ring 22 are respectively located on the radial sides of this axial plane.

[0052] In this embodiment, both the fixed capture ring 21 and the movable capture ring 22 have an inner surface located on the inside and an outer surface located on the outside. From Figure 1 and Figure 3As can be seen, in the first state, the distal end of the fixed capture ring 21 is located inside the movable capture ring 22, and similarly, the distal end of the movable capture ring 22 is located inside the fixed capture ring 21. In this embodiment, the side facing each other in the first state of the fixed capture ring 21 and the movable capture ring 22 is defined as the inner side, and the side separating them in the first state is defined as the outer side. A capture space 20a with a distal opening is formed between the fixed capture ring 21 and the movable capture ring 22. This capture space 20a is used to accommodate the target object, which can enter the capture space 20a through the distal opening. In order to make it easier for the target object to enter the capture space 20a from the distal opening in the first state, the radial distance between the distal ends of the fixed capture ring 21 and the movable capture ring 22 in this embodiment is greater than the radial distance between the proximal ends of the fixed capture ring 21 and the movable capture ring 22. The radial distance between two objects in this invention refers to the projected length of the line connecting the two objects onto the radial plane (i.e., the plane perpendicular to the axial direction).

[0053] Reference Figure 1 Both the fixed capture ring 21 and the movable capture ring 22 have annular structures. The fixed capture ring 21 has a first through-hole 230 within its annular structure, and the movable capture ring 22 has a second through-hole 240 within its annular structure. In the second state, at least a portion of the fixed capture ring 21 passes through the second through-hole 240 from the inside of the movable capture ring 22 and exits from the outside of the movable capture ring 22. At least a portion of the movable capture ring 22 is fitted over the fixed capture ring 21, such that a portion of the movable capture ring 22 (e.g., the distal end of the movable capture ring 22) is located outside the fixed capture ring 21, while another portion is located inside the fixed capture ring 21. It is understood that in other embodiments, the fixed capture ring 21 does not necessarily have an annular structure, as long as it can form an interlocking configuration in the second state, creating a capture space 20a with a distal limiting function between the fixed capture ring 21 and the movable capture ring 22.

[0054] Reference Figure 1 , Figure 2a The movable capture ring 22 may include two capture wires 211, which are arranged along the width direction of the movable capture ring 22 and connected at the distal apex 220 of the movable capture ring 22. At least one capture wire 211 is connected to a control wire 32 at its proximal end. The control wire 32 is used to move the capture wire 211 connected to it, so as to expand or contract the movable capture ring 22.

[0055] Reference Figure 2a , Figure 2bFor example, in the first state, from the proximal end to the distal end, the two capture wires 211 of the movable capture ring 22 extend in a direction away from each other to reach the maximum width 2201, then bend and extend in a direction closer to each other, and converge at the distal vertex 220. In other embodiments, the two capture wires 211 may also extend in a direction away from each other and then extend substantially parallel to each other to form the maximum width 2201 before being bent and extending in a direction closer to each other. The projections of the fixed capture ring 21 and the movable capture ring 22 onto the same preset axial plane (which is parallel to the width direction of the movable capture ring 22) have a first annular profile 201 and a second annular profile 202, respectively. In this design, the first annular contour 201 and the second annular contour 202 intersect at a point 203. Within the region distal to the intersection point 203, the first annular contour 201 lies within the second annular contour 202. Conversely, within the region proximal to the intersection point 203, the projection of the capture wire 211 connected to the control wire 32 in the movable capture ring 22 lies within the first annular contour 201. This arrangement reduces resistance as the control wire 32 moves the connected capture wire 211, allowing for more flexible and efficient control of the expansion or contraction of the movable capture ring 22. Furthermore, the larger space within the distal region of the movable capture ring 22 increases the success rate of transitioning from the fixed capture ring 21 to the second state. Because the fixed capture ring 21 and movable capture ring 22 of the capture device 100 exist in a second state, they can confine the target object within the capture space 20a between them. The size of this capture space 20a is adjustable; by reducing the size of the capture space 20a, the fixed capture ring 21 and movable capture ring 22 can exert a clamping force on the target object, thereby firmly confining the target object within the fixed capture ring 21 and movable capture ring 22, achieving a secure capture. Furthermore, when in the second state, the movable capture ring 22 is reduced by the control wire 32, causing the fixed capture ring 21 and movable capture ring 22 to cooperate in locking the target object, preventing the target object from escaping. Therefore, the capture device 100 of this embodiment can efficiently and securely capture electrode wires, greatly reducing surgical time and improving the success rate of the surgery.

[0056] Furthermore, when in the first state, the minimum axial distance between the maximum width 2201 of the movable capture ring 22 and the distal vertex 220 of the movable capture ring 22 is the first distance. The axial distance between two objects refers to the projected length of the line connecting the two objects on the axial plane. The first ratio of the first distance to the axial length of the movable capture ring 22 (the axial length of an object refers to the projected length of the line connecting the proximal and distal ends of the object on the axial plane) is less than 0.5. This setting is beneficial to further improve the flexibility of the control wire 32 in controlling the expansion or contraction of the movable capture ring 22. In some embodiments, the value of the first ratio can be in the range of 0.1 to 0.4, for example, the first ratio can be 0.4, 0.3, 0.2, 0.1, etc. This not only helps to further improve the flexibility of the control wire 32 in controlling the expansion or contraction of the movable capture ring 22, but also makes the movable capture ring 22 easier to insert into the sheath. In other embodiments, the first ratio can be greater than or equal to 0.5, for example, the first ratio can be 0.6, 0.7, 0.8, 0.9.

[0057] In this embodiment, the movable capture ring 22 has a teardrop-shaped or teardrop-like profile (for example, the outermost edge or projected profile of the movable capture ring 22 may be teardrop-shaped or teardrop-like, which is not limited in this invention), while the fixed capture ring 21 has an olive-shaped or petal-shaped profile with pointed ends along the axial direction (for example, the outermost edge or projected profile of the fixed capture ring 21 may be olive-shaped or petal-shaped with pointed ends along the axial direction, which is not limited in this invention). The curvature at the distal vertex 220 of the movable capture ring 22 is less than the curvature at the distal vertex 220 of the fixed capture ring 21. This design allows the movable capture ring 22 to have a more rounded and gentler distal end compared to the fixed capture ring 21. This results in more stable deformation of the movable capture ring 22 during expansion or contraction, reducing the risk of uncontrolled deformation and high deformation resistance caused by the distal tip being skewed during deformation. It also reduces the probability of damaging surrounding biological tissues during deformation, thus improving capture success rate and safety. Furthermore, because the fixed capture ring 21 has an olive-shaped or petal-shaped profile with pointed ends along the axial direction, it increases the success rate of inserting the fixed capture ring 21 into the movable capture ring 22, making it more effective at firmly capturing the target object. Understandably, in other embodiments, the two capture wires 211 of the fixed capture ring 21 and the movable capture ring 22 can be formed into any other suitable shape, such as ellipse, circle, rhombus, or triangle.

[0058] Furthermore, the fixed capture ring 21 has a first segment, one endpoint of which is the far vertex 210 of the fixed capture ring 21, and the other endpoint of which is located between the maximum width 2101 of the fixed capture ring 21 and the far vertex 210. The first segment has a first rate of curvature change. The movable capture ring 22 has a second segment, one endpoint of which is the far vertex 220 of the movable capture ring 22, and the other endpoint of which is located between the maximum width 2201 of the movable capture ring 22 and the far vertex 220. The second segment has a second rate of curvature change. The absolute value of the first rate of curvature change is greater than the absolute value of the second rate of curvature change. The rate of curvature change can be obtained by differentiating the curvature with respect to the arc length. This design results in less bending of the distal section of the movable capture ring 22, allowing for more stable deformation and increasing the success rate of the fixed capture ring 21 inserting into the movable capture ring 22. Therefore, it further improves the capture success rate, capture stability, and safety performance. In other embodiments, the first curvature change may be less than or equal to the second curvature change.

[0059] In this embodiment, when in the first state, the minimum axial distance between the maximum width 2101 of the fixed capture ring 21 and the distal vertex 210 of the fixed capture ring 21 is the second distance, and the second ratio of the second distance to the axial length of the fixed capture ring 21 ranges from 0.3 to 0.8. This configuration makes it easier for the distal end of the fixed capture ring 21 to penetrate the movable capture ring 22, and the distal end of the fixed capture ring 21 has a sufficient axial section to pass through the movable capture ring 22, while avoiding excessive sheathing force of the fixed capture ring 21. Exemplarily, the fixed capture ring 21 may also include two capture wires 211. In the first state, from the proximal end to the distal end, the two capture wires 211 of the fixed capture ring 21 extend in a direction away from each other to the maximum width 2101, then bend and extend in a direction closer to each other, and converge at the distal vertex 210. In other embodiments, the two capture wires 211 may extend in directions away from each other, then extend substantially parallel to each other to form the maximum width 2101, and then bend and extend in directions closer to each other. The value of the second ratio may be 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, etc. In other embodiments, the second ratio is not necessarily in the range of 0.3 to 0.8.

[0060] Furthermore, referring to Figure 3 In the first state, the fixed capture ring 21 and / or the movable capture ring 22 are curved structures that are concave in the direction away from the central axis of the capture part 20 (in this utility model, the virtual central axis of the pusher 31 is used as the central axis of the capture part 20) when viewed from the side, that is, curved structures that are concave in the direction of outward.

[0061] In this embodiment, when the capturing unit 20 is in the first state, the maximum outward deviation of the movable capturing ring 22 is less than the maximum outward deviation of the fixed capturing ring 21. The maximum outward deviation of the movable capturing ring 22 being less than the maximum outward deviation of the fixed capturing ring 21 means that, in the projections of the fixed capturing ring 21, the movable capturing ring 22, and the distal end of the pusher 31 onto the same radial plane, the maximum radial distance between the projection of the movable capturing ring 22 and the projection of the distal end of the pusher 31 is less than the maximum radial distance between the projection of the fixed capturing ring 21 and the projection of the distal end of the pusher 31.

[0062] For example, refer to Figure 4 In the diagram, the capturing unit 20 is in the first state. The maximum radial distance L2 between the projection of the movable capturing ring 22 and the projection of the far end of the pusher 31 (i.e., the radial distance from the point on the projection of the movable capturing ring 22 that is farthest from the projection of the far end of the pusher 31 to the projection of the far end of the pusher 31) is less than the maximum radial distance L1 between the projection of the fixed capturing ring 21 and the projection of the far end of the pusher 31 (i.e., the radial distance from the point on the projection of the fixed capturing ring 21 that is farthest from the projection of the far end of the pusher 31 to the projection of the far end of the pusher 31). This arrangement reduces the force required for the movable capturing ring 22 to retract.

[0063] Reference Figure 5 , Figure 6 In another embodiment, when in the first state, the annular structure of one of the fixed capture ring 21 and the movable capture ring 22 is a curved structure that is concave to the outside, and the annular structure of the other is roughly straight when viewed from the side. The whole is roughly located on the same plane. For example, the annular structure of the movable capture ring 22 is roughly located on the same plane (such as the axial plane). Being roughly located on the same plane means that there is a plane a, and the deviation distance of the annular structure of the movable capture ring 22 relative to the plane a does not exceed 2 mm. In other embodiments, the deviation distance of the annular structure of the movable capture ring 22 relative to the plane a does not exceed 0.5 mm, or 1 mm, or 1.5 mm. Figure 5 , Figure 6 The capturing part 20 in the first state also satisfies the condition that, when the capturing part 20 is in the first state, the maximum outward deviation of the movable capturing ring 22 is less than the maximum outward deviation of the fixed capturing ring 21. This arrangement reduces the force required for the contraction of the annular structure of the movable capturing ring 22 and allows for more stable deformation of the movable capturing ring 22. In other embodiments, the movable capturing ring 22 is not necessarily located approximately on the same plane. In other embodiments, the annular structure of the fixed capturing ring 21 may be approximately located on the same plane (such as the axial plane), while the annular structure of the movable capturing ring 22 is a curved structure that is concave to the outside.

[0064] Reference Figure 1, Figure 2a The capture wire 211 can be made of solid or hollow wire, which can be made of shape memory metal materials (such as nickel-titanium alloy, nickel-titanium-tantalum alloy, etc.) and / or shape memory polymer materials. The wire can also be a shape memory composite wire with developing function, such as platinum core nickel-titanium wire. It can be a single wire or a wire made of multiple wires wound together. In other embodiments, the wire can be made of materials such as stainless steel or other elastic materials. The two capture wires 211 are integrally formed; in other embodiments, the two capture wires 211 can be manufactured separately and then spliced ​​together.

[0065] In this embodiment, the proximal ends of both capture wires 211 in the fixed capture ring 21 are fixedly connected to the pusher 31 as the proximal ends of the fixed capture ring 21. The fixed connection of this invention can be a detachable fixed connection or a non-detachable fixed connection, including direct fixed connections by welding, bonding, wrapping, snap-fitting, threaded connections, etc., or fixed connections through intermediate components such as sleeves, fixing wires, and buckles. In other embodiments, the fixed capture ring 21 can also be movably connected to the pusher 31, as long as the pusher 31 can drive the fixed capture ring 21 to move axially.

[0066] The movable capture ring 22 has two capture wires 211. One capture wire 211 is fixedly connected to the pusher 31 at its proximal end, and the other capture wire 211 is fixedly connected to the control wire 32 at its proximal end. When the control wire 32 and the pusher 31 move relative to each other, the shape of the annular structure of the movable capture ring 22 can be changed, so that the annular structure of the movable capture ring 22 can expand or contract in both the first and second states. In addition, it can better maintain the orientation of the annular structure of the movable capture ring 22 in the first state, and prevent the annular structure of the movable capture ring 22 from rotating circumferentially and making it difficult to form the cross configuration of the fixed capture ring 21 in the second state. In other embodiments, the distal ends of the two capture wires 211 of the movable capture ring 21 converge to form a ring structure, and the proximal ends of both capture wires 211 are fixedly connected to the control wire 32; alternatively, the proximal and distal ends of the two capture wires 211 of the movable capture ring 21 converge to form a ring structure, and the proximal ends of both capture wires 211 are fixedly connected to the control wire 32 via other capture wires 211. In other embodiments, the movable capture ring 22 may also be movably connected to the pusher 31 and / or the control wire 32.

[0067] Understandably, in other embodiments, the proximal end of one segment of the capture wire 211 of the fixed capture ring 21 is connected to the pusher 31, and the proximal end of the other segment of the capture wire 211 is connected to the control wire 32, while the proximal end of the movable capture ring 22 is connected to the pusher 31. Alternatively, in other embodiments, within the same capture element, the proximal end of one segment of the capture wire 211 is connected to the pusher 31, and the proximal end of the other segment of the capture wire 211 is connected to the control wire 32. That is, the fixed capture ring 21 and the movable capture ring 22 are respectively connected to the corresponding control wire 32. Regardless of whether it is in the first state or the second state, the expansion or contraction of the annular structure of the fixed capture ring 21 and the annular structure of the movable capture ring 22 can be controlled by the control wire 32, and the positions of the distal ends of the fixed capture ring 21 and the movable capture ring 22 can be changed respectively. Regardless of how the connection between the fixed capture ring 21 and the movable capture ring 22 and the pusher 31 and the control wire 32 is set, as long as the control unit can change the axial distance between the far end of the fixed capture ring 21 and the far end of the movable capture ring 22, it is acceptable.

[0068] Furthermore, in this embodiment, multiple fixed capture rings 21 that cooperate with the movable capture ring 22 can be provided. The structure, shape, and cooperation method of each movable capture ring 22 and fixed capture ring 21 can be referred to the above description, and will not be repeated here.

[0069] For example, refer to Figures 7-9 The catcher 100 may include two fixed catching rings 21 and one movable catching ring 22, wherein the two fixed catching rings 21 are a first fixed catching ring 21a and a second fixed catching ring 21b. In a first state, the distal ends of the first fixed catching ring 21a and the second fixed catching ring 21b are located on opposite sides of the movable catching ring 22. For example, except for the proximal ends, the distal ends of the first fixed catching ring 21a and the second fixed catching ring 21b are all located on opposite sides of the movable catching ring 22, and the openings of their annular structures face each other. (Refer to...) Figure 10 , Figure 11 In the second state, the first fixed capture ring 21a and the second fixed capture ring 21b approach each other radially and interweave to form a cross configuration. This arrangement improves the capture success rate and is applicable to capturing target objects of various sizes. In other embodiments, the number of fixed capture rings 21 and movable capture rings 22 can be set according to actual needs.

[0070] Reference Figures 10-14When the first fixed capture ring 21 and the second fixed capture ring 21 are in an intersecting configuration, the first fixed capture ring 21 and the second fixed capture ring 21 each include a first overhanging segment 23 and a second overhanging segment 24 on the distal side of their intersecting region, respectively. From the proximal end to the distal end, the first overhanging segment 23 and the second overhanging segment 24 extend in a direction away from each other; the movable capture ring 22 can retract so that its distal end enters between the first overhanging segment 23 and the second overhanging segment 24, thereby cooperating with the first fixed capture ring 21 and the second fixed capture ring 21 to form a locking space. Since the first overhanging segment 23 and the second overhanging segment 24 together form a distal opening structure 25 that is recessed towards the proximal end, when the movable capture ring 22 retracts and enters this distal opening structure 25, the movable capture ring 22 can simultaneously cooperate with the first fixed capture ring 21 and the second fixed capture ring 21 to form locking spaces. In addition, the distal opening structure 25 can effectively restrict the distal end of the movable capture ring 22, thereby ensuring that the locking space is well maintained during the retraction of the movable capture ring 22, making it less prone to loosening and enabling more stable locking of the target object.

[0071] Reference Figure 7 In this embodiment, in the first state, the distal end of the first fixed capture ring 21a is axially closer to the proximal end of the capturer 100 than the distal end of the second fixed capture ring 21b. This arrangement makes it easier for the first fixed capture ring 21a to pass through the second fixed capture ring 21b to form a cross configuration.

[0072] Furthermore, in the first state, within the distal axial section, taking as a reference any cross-section perpendicular to the axial direction and simultaneously cutting through both the first fixed capture ring 21a and the second fixed capture ring 21b, the width of the first fixed capture ring 21a in that cross-section is smaller than the width of the second fixed capture ring 21b in that cross-section. This arrangement allows the second fixed capture ring 21b to provide a larger internal space, facilitating the passage of the first fixed capture ring 21a through the ring of the second fixed capture ring 21b. In other embodiments, taking as a reference any cross-section perpendicular to the axial direction and simultaneously cutting through both the first fixed capture ring 21a and the second fixed capture ring 21b, the width of the first fixed capture ring 21a in that cross-section is smaller than the width of the second through hole 240 in that cross-section. In other embodiments, the shapes of the first fixed capture ring 21a and the second fixed capture ring 21b can be selected according to actual needs.

[0073] Reference Figure 1 , Figure 2aIn this embodiment, the catcher 100 may further include a conduit 10, which includes a hollow tubular member having a proximal port, a distal port, and a first inner cavity connecting the proximal port and the distal port, the first inner cavity extending along the length of the conduit 10. The aforementioned pusher 31 is a hollow tubular member having a distal port and a second inner cavity connecting the distal port, the second inner cavity extending along the length of the pusher 31. The pusher 31 passes through the first inner cavity of the conduit 10 and is axially movable relative to the conduit 10. The distal end of the pusher 31 is connected to the catching part 20, which is also axially movable relative to the conduit 10. The control component is connected to the conduit 10 and the pusher 31 to change the relative positional relationship between the conduit 10 and the pusher 31, that is, to change the relative positional relationship between the conduit 10 and the catching part 20. The capturing part 20 can be completely contained within the conduit 10, or it can be released from the conduit 10 and form a first state. When the capturing part 20 in the first state moves proximally relative to the conduit and is partially compressed within the conduit 10, it switches to the second state.

[0074] Furthermore, in this embodiment, the control wire 32 can be a solid or hollow slender rod or filament, and the material used can be one or more of metals and polymers. For example, materials such as nickel-titanium alloy, stainless steel, polyester, and silicone can be selected. The radial dimension of the control wire 32 (the radial dimension refers to the width perpendicular to the length direction) can be smaller than the radial dimension of the second inner cavity, so that the control wire 32 can move axially in the second inner cavity easily. However, the radial dimension of the control wire 32 should not be too small. The radial dimension of the control wire 32 can be set to be greater than or equal to the radial dimension of the grasping wire 211, so that the control wire 32 can better transmit the pushing force, and the radial movement space of the control wire 32 in the second inner cavity can be reduced, avoiding the twisting and deformation of the grasping part 20 due to excessive movement space.

[0075] Understandably, this invention does not limit the number of control wires 32; there can be one or more. When multiple control wires 32 are present, multiple second cavities can be provided inside the pusher 31, each containing one control wire 32, allowing multiple control wires 32 to pass through different positions from the distal opening of the pusher 31 and connect to their respective grasping components. In other embodiments, the control wires 32 are not necessarily disposed in the second cavities, but can be slidably disposed in the first cavity, or disposed in any other suitable position.

[0076] Reference Figures 15-17 The following describes in detail a method for retrieving the electrode lead 200 of a cardiac implantable medical device using the catcher 100 of this embodiment. The method includes:

[0077] Step 1: The capture unit 20 is transported to a position close to the electrode wire 200 through the conduit 10. The capture unit 20 is controlled by the pusher 31 to slide relative to the conduit 10 to the distal end and be released from the conduit 10 until the fixed capture ring 21 and the movable capture ring 22 of the capture unit 20 are in the first state.

[0078] Step Two: Refer to Figure 15 Continue to control the capture unit 20 to move distally relative to the guide tube 10 so that the electrode wire 200 is located between the fixed capture ring 21 and the movable capture ring 22.

[0079] Step 3: Refer to Figure 16 The conduit 10 is pushed to move relative to the grasping part 20 toward the distal end, so that the fixed grasping ring 21 and the movable grasping ring 22 are gradually compressed into the conduit 10 from the proximal end to the distal end. Due to the compression of the conduit 10 opening, the fixed grasping ring 21 and the movable grasping ring 22 are brought closer together until the fixed grasping ring 21 and the movable grasping ring 22 form an interlaced configuration (or a cross configuration). At this time, the fixed grasping ring 21 and the movable grasping ring 22 are in the second state, thereby preventing the electrode wire 200 from coming out of the distal end of the grasping part 20.

[0080] Step Four: Refer to Figure 17 This causes the control wire 32 to move proximally, which in turn causes the distal end of the movable capture ring 22 to move toward the direction closer to the conduit 10, so that the fixed capture ring 21 and the movable capture ring 22 cooperate to form a locking space, within which the electrode wire 200 is enclosed.

[0081] Step 5: Control the capture unit 20 to move proximally relative to the conduit 10 until the capture unit 20 and the electrode wire 200 are fully loaded into the conduit 10, then remove the capture device 100 from the body to complete the retrieval of the electrode wire 200.

[0082] Understandably, the above-mentioned recovery methods may vary depending on the structure of the catcher 100, and those skilled in the art can select the appropriate recovery method according to the specific application scenario and the structure of the catcher 100.

[0083] Understandably, in another embodiment, the first and second states can be switched in other ways. The difference between this embodiment and the previous embodiment is that when the capturing unit 20 is completely released from the conduit 10, it is in the second state. The control unit 30 may include a pull line connected to the capturing unit 20, which can move the fixed capturing ring 21 and / or the movable capturing ring 22, causing the fixed capturing ring 21 and the movable capturing ring 22 in the second state to move away from each other and switch to the first state. In this embodiment, the pusher 31 may be omitted, and the capturing unit 20 may be connected to the distal end of the conduit 10, allowing the conduit 10 to push the capturing unit 20 to the vicinity of the target object.

[0084] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0085] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A trap for capturing a target object within a living organism, characterized in that, include: The capturing unit includes a fixed capturing ring and a movable capturing ring; When in the first state, the distal ends of the fixed capture ring and the movable capture ring are separated radially, forming a capture space with an opening at the distal end between them; when in the second state, the fixed capture ring and the movable capture ring are close to each other radially, and the annular structure of the movable capture ring is sleeved on the outside of the fixed capture ring. A control unit, connected to the capture unit, is used to control the fixed capture ring and the movable capture ring to switch between the first state and the second state. The control unit includes a pusher and a control wire connected to the capture unit. The movable capture ring includes two capture wires, which are arranged along the width of the movable capture ring and connected at the far apex of the movable capture ring. The proximal end of at least one capture wire is connected to the control wire, which is used to drive the capture wire connected to it to move so that the movable capture ring expands or contracts. When in the first state, the projections of the fixed capture ring and the movable capture ring on the same preset axial plane have a first annular profile and a second annular profile, respectively. The preset axial plane is parallel to the width direction of the movable capture ring. The first annular profile and the second annular profile intersect at a point. In the region on the far side of the intersection point, the first annular profile is located within the second annular profile. In the region on the near side of the intersection point, the projection of the capture wire connected to the control wire in the movable capture ring is located within the first annular profile.

2. The catcher according to claim 1, characterized in that, When in the first state, the active capture ring has a teardrop-shaped or teardrop-like profile, and the fixed capture ring has an olive-shaped or petal-shaped profile with pointed ends along the axis. The curvature at the far vertex of the active capture ring is less than the curvature at the far vertex of the fixed capture ring.

3. The catcher according to claim 1, characterized in that, When in the first state, the fixed capture ring has a first segment, one endpoint of which is the far vertex of the fixed capture ring, and the other endpoint of which is located between the maximum width of the fixed capture ring and the far vertex of the fixed capture ring. The first segment has a first rate of curvature change. The movable capture ring has a second segment, one endpoint of which is the far vertex of the movable capture ring, and the other endpoint of which is located between the maximum width of the movable capture ring and the far vertex of the movable capture ring. The second segment has a second rate of curvature change, and the absolute value of the first rate of curvature change is greater than the absolute value of the second rate of curvature change.

4. The catcher according to claim 1, characterized in that, When in the first state, the minimum axial distance between the maximum width of the active capture ring and the far vertex of the active capture ring is the first distance, and the first ratio of the first distance to the axial length of the active capture ring is less than 0.

5.

5. The catcher according to claim 4, characterized in that, The projection of the maximum width of the active capture ring is located on the far side of the intersection, and the first ratio ranges from 0.1 to 0.

4.

6. The catcher according to claim 1, characterized in that, When in the first state, the minimum axial distance between the maximum width of the fixed capture ring and the far vertex of the fixed capture ring is the second distance, and the second ratio of the second distance to the axial length of the fixed capture ring is in the range of 0.3 to 0.

8.

7. The catcher according to claim 1, characterized in that, When in the first state, the maximum outward deviation of the movable capture ring is less than the maximum outward deviation of the fixed capture ring. The maximum outward deviation of the movable capture ring is less than the maximum outward deviation of the fixed capture ring, meaning that in the projections of the fixed capture ring, the movable capture ring, and the distal end of the pusher on the same radial plane, the maximum radial distance between the projection of the movable capture ring and the projection of the distal end of the pusher is less than the maximum radial distance between the projection of the fixed capture ring and the projection of the distal end of the pusher.

8. The catcher according to claim 1, characterized in that, When in the first state, the fixed capture ring has a curved structure that is concave to the outside, and the movable capture ring is approximately located on the same plane. The movable capture ring being approximately located on the same plane means that there is a plane a, and the deviation distance of the movable capture ring relative to the plane a does not exceed 2mm.

9. The catcher according to claim 1, characterized in that, After being in the second state, the movable capture ring can retract to cooperate with the fixed capture ring to form a locking space that can limit the distal end, so that the capture part changes from the second state to the third state. When in the third state, the distal end of the fixed capture ring is axially further away from the proximal end of the capture part than the distal end of the movable capture ring.

10. The catcher according to any one of claims 1 to 9, characterized in that, The catcher includes two fixed catching rings and one movable catching ring. The two fixed catching rings are a first fixed catching ring and a second fixed catching ring, respectively. When in the first state, the distal ends of the first fixed catching ring and the distal ends of the second fixed catching ring are located on opposite sides of the movable catching ring. When in the second state, the first fixed catching ring and the second fixed catching ring are radially close to each other and interweave to form a cross configuration.

11. The catcher according to claim 10, characterized in that, When the first fixed capture ring and the second fixed capture ring are in an intersecting configuration, the first fixed capture ring and the second fixed capture ring each include a first overhang segment and a second overhang segment on the far side of their intersecting area, extending from the proximal end to the distal end, with the first overhang segment and the second overhang segment extending in a direction away from each other; the movable capture ring can retract to allow the distal end of the movable capture ring to enter between the first overhang segment and the second overhang segment, so as to cooperate with the first fixed capture ring and the second fixed capture ring to form a locking space.

12. The catcher according to any one of claims 1 to 9, characterized in that, The catcher further includes a conduit having a first inner cavity extending axially; a pusher having a second inner cavity extending axially, the control wire passing through the second inner cavity and movable axially relative to the pusher; the pusher passing through the first inner cavity and movable axially relative to the conduit, the distal end of the pusher being connected to the catching part to drive the catching part to move axially relative to the conduit, so that the catching part can be completely contained within the conduit, or released from the conduit and forming a first state; when the catching part in the first state moves proximally relative to the conduit and is partially compressed within the conduit, it switches to the second state; the proximal end of the fixed catching ring is fixedly connected to the pusher, one end of the catching wire of the movable catching ring is fixedly connected to the pusher, and the other end of the catching wire is fixedly connected to the control wire.

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