Pushing core wire of medical implant and medical device

Abstract

The present invention provides a medical implant push core wire and a medical device. The push core wire is used to push the medical implant and includes a cannula assembly, a core shaft, and a retrieval assembly. The core shaft is movably disposed in the cannula assembly. The retrieval assembly includes a retrieval portion and a support portion. The retrieval assembly has a first state and a second state. When the retrieval assembly is in the first state, the retrieval assembly is configured to maintain a predetermined distance from the medical implant; when the retrieval assembly is in the second state, the retrieval assembly is configured to at least partially press against the medical implant or insert into a pore of the medical implant to retrieve the medical implant. The push core wire can reduce resistance during the pushing process and the first release process, particularly resistance when the medical implant is in a curved state while passing through a curved path, and solve the problem of withdrawing and retrieving the medical implant.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a pushing core wire of a medical implant and a medical device. Background Art

[0002] Aneurysms are serious arterial vascular diseases that cause damage to the human body in two main ways. First, as the aneurysm enlarges, it compresses surrounding nerves and arteriovenous tissue, causing discomfort or partial loss of function. Second, rupture of the aneurysm due to aging of the aneurysm wall or external factors can be life-threatening. In particular, cerebral aneurysm ruptures can cause strokes, which have a high mortality and disability rate. In recent years, with improvements in living standards and environmental degradation, the incidence of aneurysms has increased year by year.

[0003] Among aneurysms, intracranial aneurysms are the most difficult to treat. Currently, the recognized low-risk treatment for intracranial aneurysms is minimally invasive interventional therapy. Minimally invasive interventional therapy has the advantages of less trauma, faster cure, low recurrence rate and fewer sequelae. Minimally invasive interventional therapy refers to the implantation of a permanent medical implant, such as a dense mesh stent, at the site of vascular lesions. The medical implant is used to block blood from entering the aneurysm, thereby reducing the blood supply to the aneurysm and promoting aneurysm shrinkage. At the same time, the medical implant is also used to support the blood vessel wall around the aneurysm to ensure normal blood circulation in the blood vessels.

[0004] During minimally invasive interventional treatment, the operator uses a delivery system to push a medical implant to the diseased vessel. During this process, the implant's position and posture must be adjusted based on the actual delivery situation. Therefore, it is desirable for the delivery system to have good retraction performance and low resistance to facilitate retrieving and re-deploying the released implant. Summary of the Invention

[0005] The present invention aims to provide a push core wire for a medical implant and a medical device, which are designed to enable the medical implant to be recovered and adjusted according to the actual release situation when the medical implant is pushed to a target site by the push core wire and then released, while reducing the pushing resistance caused by the fixed shape of the push core wire or the continuous radial outward squeezing of the medical implant during the pushing process, especially from the proximal end to the distal end of a delivery tube (such as a microcatheter) and through a curved path.

[0006] To achieve the above-mentioned object, the present invention provides a pushing core wire for a medical implant, which is used for pushing a medical implant. The pushing core wire comprises:

[0007] A cannula assembly comprising a tube body and a push block disposed at a proximal end of the tube body, wherein the push block and the tube body remain relatively stationary and the push block is configured to abut against the proximal end of the medical implant;

[0008] a core shaft partially passing through the tube body and capable of moving along the axial direction of the tube body, with the distal end of the core shaft exposed outside the distal end of the tube body; and

[0009] a recovery assembly located outside the distal end of the cannula and comprising a recovery portion and a support portion; the recovery portion is connected to the cannula and arranged on the periphery of the core shaft; the support portion is disposed on the core shaft and remains relatively stationary with respect to the core shaft in the axial direction;

[0010] The pushing core wire has a first state and a second state, and is configured as follows: when the pushing core wire is in the first state, the support portion is at least partially located on the distal side of the recovery portion, and the recovery component is used to maintain a predetermined distance from the medical implant; when the pushing core wire is in the second state, the support portion applies a force to the recovery portion and causes the recovery portion to expand radially outward along the core shaft so as to at least partially press against the medical implant or insert into the pore of the medical implant.

[0011] Optionally, the recovery portion is an elastic sleeve, and the proximal end of the elastic sleeve is fixedly connected to the sleeve assembly, and the distal end of the elastic sleeve is a free end;

[0012] When the pushing core wire is in the second state, the support portion applies an extrusion force from the distal end of the core shaft to the proximal end of the elastic sleeve at the distal end of the elastic sleeve, and compresses the elastic sleeve axially and expands radially outward.

[0013] Optionally, the recovery portion comprises a base and a feeler, the proximal end of the base is connected to the sleeve assembly, and the distal end of the base extends along the axial direction of the sleeve assembly; at least one of the feelers is provided on a side of the base away from the core shaft;

[0014] When the pushing core wire is in the second state, the support portion is at least partially located between the base and the core shaft, and applies a radially outward support force to the base along the core shaft, causing the base to expand radially; at least one of the tentacles is used to be inserted into the pore of the medical implant or pressed against the inner surface of the medical implant.

[0015] Optionally, there is a gap between the inner surface of the base and the side wall of the core shaft. When the pushing core wire is in the first state, the inner surface of the base and the side wall of the core shaft are parallel to each other, or when the pushing core wire is in the first state, the gap between the inner surface of the base and the side wall of the core shaft gradually decreases from the proximal end to the distal end.

[0016] Optionally, the recovery portion includes a plurality of bases, which are arranged at intervals around the axis of the core shaft, and each of the bases is provided with the tentacles.

[0017] Optionally, the recovery portion further includes an annular connector, and the proximal end of the base is disposed on the annular connector and is connected to the sleeve via the annular connector.

[0018] Optionally, the annular connector is connected to the tube body, or the annular connector is connected to the distal end surface of the pushing block.

[0019] Optionally, the support portion includes a first wedge-shaped segment, and a distance from an outer surface of the first wedge-shaped segment to a side wall of the core shaft gradually increases in a direction from the proximal end to the distal end;

[0020] When the pushing core wire is in the first state, the first wedge segment is at least partially located on the distal side of the recovery portion; when the recovery component is in the second state, the first wedge segment is at least partially located between the recovery portion and the core shaft.

[0021] To achieve the above object, the present invention further provides a medical device comprising:

[0022] sheath;

[0023] A push core wire of the medical implant as described in any of the preceding items, wherein the push core wire is partially disposed in the sheath tube and is movable along the axial direction of the sheath tube; and

[0024] A medical implant is compressed in the sheath tube and sleeved on the outer surface of the pushing core wire and located at the distal end of the pushing block;

[0025] The medical device is configured such that, when the retrieval component is in the first state, the pushing block is used to abut against the proximal end of the medical implant; and when the retrieval component is in the second state, the retrieval portion is at least partially pressed against the inner surface of the medical implant or inserted into the pore of the medical implant.

[0026] Optionally, the medical implant is a medical stent.

[0027] Compared with the prior art, the push core wire of the medical implant and the medical device of the present invention have the following advantages:

[0028] The aforementioned pushing core wire of a medical implant is used for pushing a medical implant, and the pushing core wire comprises: a sleeve assembly, comprising a tube body and a pushing block arranged at the proximal end of the tube body, the pushing block and the tube body remain relatively stationary, and the pushing block is used to abut against the proximal end of the medical implant; a core shaft, partially passed through the tube body and capable of moving along the axial direction of the tube body, and the distal end of the core shaft is exposed outside the distal end of the tube body; and a recovery assembly, located outside the distal end of the sleeve, and comprising a recovery part and a support part; the recovery part is connected to the sleeve and arranged on the outer periphery of the core shaft; the support part is arranged on the core shaft and remains relatively stationary with the core shaft in the axial direction; the pushing core wire has a first state and a second state. When the pushing core wire is used to push and release the medical implant for the first time, the pushing core wire is in the first state, at which time the support portion is at least partially located on the distal side of the retrieval portion, and a predetermined distance is maintained between the retrieval component and the inner surface of the medical implant so that there is no interaction force between the two, thereby reducing resistance and reducing the possibility of debris generated by friction between the retrieval component and the medical implant or tubing (such as a sheath and a microcatheter) during the pushing process, thereby causing thrombosis, thereby improving the safety of treatment and ensuring the treatment effect; during the release of the medical implant, if the posture of the medical implant is not good, the operator can switch the pushing core wire to the second state by performing corresponding operations. At this time, the support portion applies a force to the retrieval portion and causes the retrieval portion to expand radially to be able to press against the inner surface of the medical implant or insert into the pore of the medical implant, so that the operator can retrieve the medical implant, thereby readjusting the posture of the medical implant and releasing it. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings are provided for a better understanding of the present invention and are not intended to limit the present invention.

[0030] Figure 1 1 is a schematic diagram of a pushing core wire of a medical implant according to an embodiment of the present invention pushing a medical stent in a microcatheter, wherein the recovery component is in a first state;

[0031] Figure 2 1 is a schematic diagram of a medical stent being recovered by a pushing core wire of a medical implant provided by one embodiment of the present invention, wherein the recovery component is in a second state;

[0032] [The following are the descriptions of the reference numerals]:

[0033] 10-medical stent, 20-microcatheter;

[0034] 100-sleeve assembly, 110-tube body, 120-pushing block;

[0035] 200-mandrel;

[0036] 300 - recovery component, 310 - recovery part, 311 - base, 312 - antenna, 313 - annular connector, 320 - support part, 321 - first wedge-shaped segment, 322 - straight segment, 323 - second wedge-shaped segment. DETAILED DESCRIPTION

[0037] The following describes the embodiments of the present invention through specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner, and the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components during actual implementation. During actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0038] In addition, each embodiment described below has one or more technical features. However, this does not mean that users of the present invention must implement all technical features in any embodiment at the same time, or that they can only implement some or all technical features in different embodiments separately. In other words, as long as implementation is possible, those skilled in the art can, based on the disclosure of the present invention and depending on design specifications or implementation requirements, selectively implement some or all technical features in any embodiment, or selectively implement a combination of some or all technical features in multiple embodiments, thereby increasing the flexibility of the implementation of the present invention.

[0039] As used in this specification, the singular forms "a", "an", and "the" include plural objects, and the plural form "a plurality" includes more than two objects, unless the content clearly indicates otherwise. As used in this specification, the term "or" is generally used in a sense including "and / or", unless the content clearly indicates otherwise, and the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be directly connected or indirectly connected through an intermediate medium, and it can be a connection between the internal parts of two elements or an interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0040] As used herein, the terms "proximal" and "distal" refer to the relative orientation, position, and direction of components or actions relative to each other from the perspective of an operator using the medical device. Although "proximal" and "distal" are not restrictive, "proximal" generally refers to the end of the medical device that is closest to the operator during normal operation, while "distal" generally refers to the end that first enters the patient's body.

[0041] The core idea of the present invention is to provide a pushing core wire of a medical implant for pushing a medical implant, wherein the pushing core wire comprises: a sleeve assembly, comprising a tube body and a pushing block arranged at the proximal end of the tube body, wherein the pushing block and the tube body remain relatively stationary, and the pushing block is used to abut against the proximal end of the medical implant; a core shaft, which is partially inserted into the tube body and can move along the axial direction of the tube body, and the distal end of the core shaft is exposed outside the distal end of the tube body; and a recovery assembly, which is located outside the distal end of the sleeve and comprises a recovery part and a support part; the recovery part is connected to the sleeve and arranged on the periphery of the core shaft ; The support portion is arranged on the core shaft and remains relatively stationary with the core shaft in the axial direction; the pushing core wire has a first state and a second state, and the pushing core wire is configured as follows: when the pushing core wire is in the first state, the support portion is at least partially located on the distal side of the recovery portion, and the recovery component is used to maintain a predetermined distance from the medical implant; when the pushing core wire is in the second state, the support portion applies a force to the recovery portion and causes the recovery portion to expand radially outward along the core shaft, so as to be used to at least partially press against the medical implant or insert into the pore of the medical implant.

[0042] When the push core wire is in the first state, the operator can use the push core wire to push the medical implant to the target position in the patient's body and perform the first release. During this process, since the retrieval component and the medical implant maintain a predetermined distance so that there is no interaction force between the two, the resistance during the pushing and first release of the medical implant can be effectively reduced, and the possibility of insoluble particles being generated due to friction between the retrieval component and the medical implant and / or tubing (such as a sheath and a microcatheter, which will be described below) and thus causing thrombosis is also reduced. During the process of releasing the medical stent, as long as the medical implant is not completely released (i.e., the medical implant is at least partially located in the microcatheter), the operator can switch the push core wire to the second state by performing corresponding operations and use the retrieval component to achieve the retrieval of the medical implant. Afterwards, the operator can adjust the position of the medical implant and release it again.

[0043] Those skilled in the art will appreciate that the medical implant includes a medical stent, an embolic coil, an occluder, a flow disruptor, an obturator, a valve, or other medical implants having a non-smooth continuous inner wall (e.g., a mesh structure, a corrugated structure, a hole structure, etc.). The target location may be a location on a blood vessel where an aneurysm has formed.

[0044] Furthermore, the present invention also provides a medical device, comprising the aforementioned pushing core wire of the medical implant, a medical implant and a sheath; the pushing core wire is partially inserted into the sheath and can move axially along the sheath. The medical implant is compressed in the sheath and is sleeved on the outer surface of the pushing core wire and is located on the distal side of the pushing block. When the recovery component is in the first state, the pushing block is used to abut against the proximal end of the medical implant. When the recovery component is in the second state, the recovery part is at least partially pressed against the medical implant or inserted into the pores of the medical implant.

[0045] To make the objects, advantages, and features of the present invention more apparent, the present invention is further described below in detail with reference to the accompanying drawings. It should be noted that the drawings are greatly simplified and not to exact scale, and are intended solely to facilitate and clearly illustrate the embodiments of the present invention. The same or similar reference numerals in the drawings represent the same or similar components.

[0046] The embodiment of the present invention provides a push core wire of a medical implant, such as Figure 1 and Figure 2As shown, the pushing core wire includes a sleeve assembly 100, a core shaft 200 and a recovery assembly 300. The sleeve assembly 100 includes a tubular body 110 and a pushing block 120. The tubular body 110 has a first inner cavity that is axially through, and the first inner cavity is used to load the core shaft 200. The pushing block 120 is arranged at the proximal end of the tubular body 110 and remains relatively stationary with the tubular body 110. The pushing block 120 is used to abut against the proximal end of the medical implant so that the pushing block 120 can move synchronously with the tubular body 110 and push the medical stent 10 to the distal end. The core shaft 200 is partially inserted into the first inner cavity and can move axially along the first inner cavity, and the distal end of the core shaft 200 is exposed outside the tubular body 110. The recovery assembly 300 is located outside the distal end of the sleeve 100 and includes a recovery portion 310 and a support portion 320. The recovery portion 310 is connected to the sleeve assembly 100. The support portion 320 is disposed on the core shaft 200 and remains relatively stationary in the axial direction with the core shaft 200. In this way, the support portion 320 can move axially synchronously with the core shaft 200 and can generate axial relative movement with the recovery portion 310. Here, the support portion 320 can be formed separately from the core shaft 200 and then connected, or it can be formed integrally.

[0047] The push core wire has a first state and a second state, and the push core wire is configured such that when the push core wire is in the first state, the support portion 320 is at least partially located on the distal side of the retractor portion 310, and the entire retractor assembly 300 is used to maintain a predetermined distance from the medical implant, so that there is no contact between the retractor assembly 300 and the medical implant, thereby achieving zero interaction force. When the push core wire is in the second state, the support portion 320 is at least partially located between the retractor portion 310 and the core shaft 200, and the support portion 320 applies a radially outward support force to the retractor portion 310 along the core shaft 200, causing the retractor portion 310 to expand radially outward, and the expanded retractor portion 310 is used to at least partially press against the medical implant or be inserted into a pore of the medical implant.

[0048] Those skilled in the art will appreciate that the push core wire is used to cooperate with a sheath (not shown in the figure) to introduce the medical implant into a delivery tube, such as a microcatheter 20, and then the push core wire is used to push the medical implant along the microcatheter 20 to the target position in the patient's body and then release it (the specific method will be described later). Therefore, an embodiment of the present invention also provides a medical device, comprising the push core wire, a medical implant and the sheath. This embodiment is described by taking the medical implant as a medical stent 10 as an example. The sheath has a second inner cavity extending axially therethrough, and the second inner cavity is used to load the push core wire and the medical stent 10. The push core wire is partially inserted into the second inner cavity. The medical stent 10 is compressed in the second inner cavity and is sleeved on the outer surface of the push core wire and is located on the distal side of the push block 120.

[0049] When using the medical device, the medical stent 10 and the pushing core wire are first introduced into the microcatheter 20 through the sheath tube, and then the medical stent 10 is pushed to the target position in the patient's body along the microcatheter 20 for release. Specifically, the operator applies a pushing force to the pushing core wire along the proximal end of the pushing core wire pointing to the distal end, so that the sleeve assembly 100 and the core shaft 200 move synchronously, and the pushing force is transmitted to the medical stent 10 through the pushing block 120 to push the medical stent 10 toward the distal end of the microcatheter 20 until the distal end of the medical stent 10 reaches the distal end of the microcatheter 20. Thereafter, the microcatheter 20 is withdrawn to release the medical stent 10 (i.e., the first release). During this process, the retrieval assembly 300 of the pushing core wire is preferably in the first state. This has the advantage that, when pushing and releasing the medical stent 10 for the first time, there is no interaction force between the medical stent 10 and / or the microcatheter 20 and the retrieval assembly 300, thereby reducing resistance and the possibility of debris generated by friction between the retrieval assembly 300 and the medical stent 10 and / or the microcatheter 20, thereby reducing the probability of adverse consequences such as thrombosis. Before the medical stent 10 is fully released, that is, when a portion of the medical stent 10 is still located in the microcatheter 20, for example, when the distal end of the retrieval portion 310 has not yet exceeded the distal end of the microcatheter 20, if the position of the medical stent 10 does not meet the expected state, the operator can perform corresponding operations to switch the retrieval assembly 300 to the second state, and then apply a retraction force to the pushing core wire to retract the medical stent 10, and then release the medical stent 10 again after adjusting the position of the medical stent 10.

[0050] That is to say, the pushing core wire and treatment device provided in the embodiment of the present invention can not only solve the problem of recycling the medical stent 10 during the release process, but also effectively reduce the resistance of the medical stent 10 during pushing and the first release, especially the resistance when the stent passes through the bending part and is in a bent state. It can also reduce the possibility of debris generated by friction and then causing thrombosis during the entire implantation operation, improve the reliability and safety of the implantation operation, and reduce the risk of immediate thrombotic complications.

[0051] Please continue to refer to Figure 1 and Figure 2 In a disclosed embodiment, the recovery portion 310 of the recovery assembly 300 includes a base 311, a feeler 312, and an annular connector 313. The annular connector 313 is sleeved on the core shaft 200 and can be connected to the distal end of the tube body 110 or the distal end surface of the push block 120 (not shown in the figure). The base 311 extends along the axial direction of the core shaft 200, and the proximal end of the base 311 is connected to the annular connector 313. At least one of the feelers 312 is provided on the outer surface of the base 311. The "outer surface" refers to the surface of the base 311 away from the core shaft 200.

[0052] In the therapeutic device, when the retrieving assembly 300 is in the first state, the base 311 and all of the tentacles 312 maintain a predetermined spacing from the medical stent 10, which should be understood to be greater than zero. When the retrieving assembly 300 is in the second state, the base 311 and the support portion 320 remain relatively stationary in the axial direction, and the base 311, under the action of the support portion 320, deforms toward the medical stent 10, causing at least one of the tentacles 312 to insert into an aperture in the medical stent 10 or press against the inner sidewall of the medical stent 10. If the pressing force is sufficient, the medical stent 10 can be retracted under the action of the pressing force. If the pressing force is insufficient, the medical stent 10 and the mandrel 200 will initially move relative to each other, causing the tentacles 312 to move into the apertures of the medical stent 10, and then the medical stent 10 will be retracted synchronously with the mandrel. That is, in this embodiment, the recovery assembly 300 is used to connect the medical stent 10 to the core shaft 200 so that the medical stent 10 can remain relatively stationary with the core shaft 200 in the axial direction, and thus can perform axial synchronous movement with the core shaft 200.

[0053] The recovery portion 310 includes a plurality of bases 311, which are arranged at intervals around the axis of the core shaft 200, and each of the bases 311 is provided with a tentacles 312. The number of the tentacles 312 provided on each of the bases 311 can be the same or different, and the positions of the tentacles 312 provided on different bases 311 in the axial direction of the core shaft 200 can be the same or different, which is not limited by the present invention. Preferably, the plurality of bases 311 are evenly arranged around the axis of the core shaft 200, so that the recovery portion 310 can be connected to the medical stent 10 at multiple positions in the circumferential direction to improve the force balance of the recovery portion 310.

[0054] Optionally, a gap is provided between the inner surface of the base 311 and the sidewall of the mandrel 200. When the recovery assembly 300 is in the first state, the inner surface of the base 311 and the sidewall of the mandrel 200 are parallel to each other, or the gap between the inner surface of the base 311 and the sidewall of the mandrel 200 gradually decreases from the proximal end to the distal end. The "inner surface" herein refers to the surface of the base 311 that is close to the mandrel 200.

[0055] To ensure smooth insertion of the support portion 320 of the recovery assembly 300 between the recovery portion 310 and the sidewall of the mandrel 200, the support portion 320 in this embodiment includes a first wedge-shaped segment 321. The distance between the outer surface of the first wedge-shaped segment 321 and the sidewall of the mandrel 200 gradually increases from the proximal end to the distal end. When the recovery assembly 300 is in the first state, the first wedge-shaped segment 321 is at least partially located at the distal end of the recovery portion 310. When the recovery assembly 300 is in the second state, the first wedge-shaped segment 321 is at least partially located between the recovery portion 310 and the mandrel 200. In other words, in this embodiment, the mandrel 200 drives the first wedge segment 421 to move in the distal-to-proximal direction, gradually increasing the portion of the first wedge segment 321 located between the recovery portion 310 and the mandrel 200, thereby switching the core wire pushing from the first state to the second state.

[0056] It should be understood that the first wedge segment 321 may extend continuously along the circumference of the core shaft 200, or may be a discontinuous structure, i.e., the first wedge segment 321 may include a plurality of sub-wedge segments spaced apart along the circumference of the core shaft 200. Furthermore, on a plane parallel to the axis of the core shaft 200, the edge line of the projection of the outer surface of the first wedge segment 321 may be either a straight line or a curve. Thus, the first wedge segment 321 may be a conical structure or a portion of a spherical or ellipsoidal surface, as long as it can be inserted between the recovery portion 310 and the core shaft 200. This is not a limitation of the present invention.

[0057] It should also be understood that the support portion 320 may further include a straight section 322 disposed at the distal end of the first wedge-shaped section 321. The distance between the outer surface of the straight section 322 and the sidewall of the mandrel 200 may be equal to the maximum distance between the outer surface of the first wedge-shaped section 321 and the sidewall of the mandrel 200, thereby providing a more stable support force for the recovery portion 310. Alternatively, a second wedge section 323 may be disposed at the distal end of the first wedge-shaped section 321, wherein the distance between the outer surface of the second wedge section 323 and the sidewall of the mandrel 200 gradually decreases from the proximal end to the distal end. In other words, the support portion 320 includes at least the first wedge-shaped section 321, and other structures may be disposed at the distal end of the first wedge-shaped section 321.

[0058] Preferably, the recovery assembly 300 also has a developing feature, for example, developing elements are provided on the recovery portion 310 and the support portion 320. This facilitates monitoring the relative position of the recovery portion 310 and the support portion 320 via a developing device during use, thereby determining the status of the recovery assembly 300. Alternatively, the retractable distance between the tube body 110 and the support portion 320 can be pre-calibrated using a positioning structure, and the recovery portion 310 can be fully opened by directly retracting the retracted portion during use.

[0059] The following describes the method of using the medical device. It should be understood that before use, the recovery assembly 300 of the pushing core wire is in the first state.

[0060] First, the operator constructs the microcatheter 20 in the patient's body, with the distal end of the microcatheter 20 extending to the target location.

[0061] Next, the operator introduces the medical device into the microcatheter 20 under the monitoring of a developing device such as an X-ray device. To facilitate operation, the distal end of the sheath is preferably designed to be a tapered structure.

[0062] Next, the operator applies a pushing force to the proximal end of the pushing core wire so that the sleeve assembly 100 and the core shaft 200 move toward the distal end of the sheath tube at the same time, and uses the pushing block 120 to transmit the pushing force to the medical stent 10, so that the pushing core wire carries the medical stent 10 into the microcatheter 20 and retracts the sheath tube.

[0063] Next, the operator continues to apply a pushing force to the proximal end of the pushing core wire to make the sleeve assembly 100 and the core shaft 200 move synchronously. The pushing core wire carries the medical stent 10 in the microcatheter 20 until the distal end of the medical stent 10 reaches the distal end of the microcatheter 20.

[0064] Next, the operator applies a retraction force (a force directed from the distal end toward the proximal end) to the proximal end of the microcatheter 20 to retract the microcatheter 20 , thereby performing the first release of the medical stent 10 .

[0065] If the position of the medical stent 10 during the release process always meets the expected position, the operator can continuously withdraw the microcatheter 20 to completely release the medical stent 10 (ie, only perform the release process once).

[0066] If the posture of the medical stent 10 is not good during the release process of the medical stent 10, the operator can apply a retraction force to the proximal end of the core shaft 200 to make the core shaft 200 carry the support part 320 and move toward the proximal end of the microcatheter 20 (the sheath assembly 100 remains stationary during this process), so that the support part 320 is inserted between the base 311 of the recovery part 310 and the core shaft 200 (taking the first state as an example, when the support part 320 is entirely located on the distal side of the recovery part 310). Because the distance between the surface of the first wedge-shaped segment 321 of the support portion 320 and the sidewall of the core shaft 200 gradually increases from the proximal end to the distal end, as the first wedge-shaped segment 321 gradually inserts more and more between the recovery portion 310 and the core shaft 200, the support portion 320 applies a radially outward supporting force to the base 311 along the core shaft 200, causing the base 311 to gradually approach the inner surface of the medical stent 10 (i.e., the recovery portion 310 deforms) until the antennae 312 on the base 311 insert into the pores of the medical stent 10, thereby connecting the core shaft 200 to the medical stent 10 and maintaining axial relative stillness between the core shaft 200 and the medical stent 10. Subsequently, the operator can apply a pushing force to the proximal end of the microcatheter 20 to push the microcatheter 20 and recover the released medical stent 10. It should be noted that the tentacles 312 on the base 311 may also press against the inner surface of the medical stent 10, but when the microcatheter 20 is pushed thereafter, the friction between the microcatheter 20 and the medical stent 10 may cause the medical stent 10 to move slightly, so that the tentacles 312 are inserted into the pores of the medical stent 10.

[0067] After completing the recovery of the medical stent 10 , the operator can adjust the posture of the medical stent 10 and release the medical stent 10 again.

[0068] After the medical stent 10 is released, the operator applies a pushing force to the proximal end of the microcatheter 20 to push the microcatheter 20 so that the pushing core wire completely enters the microcatheter 20. Finally, the operator withdraws the microcatheter 20 and the pushing core wire from the body.

[0069] It should be understood that in the above embodiment, the annular connector 313 of the recovery component 300 is not necessary. When the proximal end of the base 311 is directly connected to the distal end of the tube body 110 (or directly connected to the pushing block 120), the annular connector 313 can be omitted.

[0070] In an alternative embodiment, the retrieval portion 310 of the retrieval assembly 300 is an elastic sleeve, the proximal end of which is fixedly connected to the cannula assembly 100, and the distal end of which is free. Thus, when the core wire is in the second state, the support portion 320 can apply an axial compressive force from the distal end of the elastic sleeve toward the proximal end of the core shaft 200, causing the elastic sleeve to expand radially outward under the action of the support portion 320. This is because the volume of the elastic sleeve can be approximately constant under the system force level, and axial compression along the core shaft 200 will inevitably cause the elastic sleeve to expand radially outward along the core shaft 200. In this way, at least a portion of the outer surface of the elastic sleeve can press against the inner surface of the medical stent 10, resulting in a high friction force between the outer surface of the elastic sleeve and the inner surface of the medical stent 10. This friction force enables the medical stent 10 to remain axially stationary relative to the elastic sleeve 200. The operator can then push the microcatheter 20 to retrieve the medical stent 10. It should be noted that the support portion 320 may be partially inserted between the elastic sleeve and the core shaft, or the support portion 320 may be entirely located at the distal end of the elastic sleeve.

[0071] In the technical solution provided by the embodiments of the present invention, during delivery and initial release of the medical implant, the recovery assembly of the core wire is placed in the first state. This eliminates any force acting between the recovery assembly and the medical implant, thereby reducing frictional resistance between the medical implant and the delivery tube. It is well known that frictional resistance between the medical implant and the delivery tube does not contribute to the advancement of the medical implant within the delivery tube. Instead, it can cause scraping between the medical implant and the inner wall of the delivery tube due to compression of the medical implant. This scraping phenomenon is particularly prone to occur when the medical implant passes through a curved area. Delivery tubes are typically made of polymer materials, and scraping between the medical implant and the core wire can easily generate insoluble particles, thereby increasing the risk of thrombosis caused by these particles. Pushing the medical implant from the proximal end of the delivery tube to the distal outlet of the delivery tube until it reaches the target release site is a necessary path for interventional surgery. During this path, scraping between the medical implant and the delivery tube, as well as the insoluble particles resulting from this scraping, should be minimized and avoided in clinical practice. Taking the implantation of medical implants into cardiovascular systems as an example, the length of the delivery tube is generally more than 500 mm, while the length of the delivery tube used to implant medical implants into cerebral blood vessels is even longer, generally more than 1000 mm. Compared with the intraoperative release length of the implant device itself, it occupies the vast majority of the friction distance with the delivery tube. Insoluble particles generated during the delivery process will eventually be transported into the blood vessels as the medical implant is pushed. After the implant device is implanted, the delivery system is withdrawn, and the space inside the sheath itself is larger, making it less likely to produce debris. Even if debris is produced, most of it will be carried out of the body by the delivery system while maintaining outward blood pressure. It can be seen from this that the push core wire provided in the embodiment of the present invention can effectively reduce resistance during the push and first release of the medical implant, and reduce the risk of debris generated by friction and causing thrombosis. When the recovery component is switched to the second state, the released medical implant can be recovered, making it convenient to adjust the position of the medical implant.

[0072] While the present invention is disclosed above, it is not limited thereto. Those skilled in the art may make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, the present invention is intended to encompass such modifications and variations as long as they fall within the scope of the claims and their equivalents.

Claims

1. A pushing core wire for a medical implant, used for pushing a medical implant, characterized in that: The pushing core wire comprises: A cannula assembly comprising a tube body and a push block disposed at a proximal end of the tube body, wherein the push block and the tube body remain relatively stationary and the push block is configured to abut against the proximal end of the medical implant; a core shaft partially passing through the tube body and capable of moving along the axial direction of the tube body, with the distal end of the core shaft exposed outside the distal end of the tube body; and A recovery assembly is located outside the distal end of the sleeve assembly and includes a recovery portion and a support portion; the recovery portion is provided on the sleeve assembly and arranged on the periphery of the core shaft; the support portion is provided on the core shaft and remains relatively stationary with the core shaft in the axial direction; The pushing core wire has a first state and a second state, and is configured as follows: when the pushing core wire is in the first state, the support portion is at least partially located on the distal side of the recovery portion, and the recovery component is used to maintain a predetermined distance from the medical implant; when the pushing core wire is in the second state, the support portion applies a force to the recovery portion and causes the recovery portion to expand radially outward along the core shaft so as to at least partially press against the medical implant or insert into the pore of the medical implant.

2. The push core wire of the medical implant according to claim 1, characterized in that: The recovery portion is an elastic sleeve, and the proximal end of the elastic sleeve is fixedly connected to the sleeve assembly, and the distal end of the elastic sleeve is a free end; When the pushing core wire is in the second state, the support portion applies an extrusion force from the distal end of the core shaft to the proximal end of the elastic sleeve at the distal end of the elastic sleeve, and compresses the elastic sleeve axially and expands radially outward.

3. The pushing core wire of the medical implant according to claim 1, characterized in that The recovery portion includes a base and a feeler, wherein the proximal end of the base is provided on the sleeve assembly, and the distal end of the base extends along the axial direction of the sleeve assembly; at least one of the feelers is provided on a side of the base away from the core shaft; When the pushing core wire is in the second state, the support portion is at least partially located between the base and the core shaft, and applies a radially outward support force to the base along the core shaft, causing the base to expand radially; at least one of the tentacles is used to be inserted into the pore of the medical implant or pressed against the inner surface of the medical implant.

4. The pushing core wire of the medical implant according to claim 3, characterized in that There is a gap between the inner surface of the base and the side wall of the core shaft. When the pushing core wire is in the first state, the inner surface of the base and the side wall of the core shaft are parallel to each other, or when the pushing core wire is in the first state, the gap between the inner surface of the base and the side wall of the core shaft gradually decreases from the proximal end to the distal end.

5. The pushing core wire of the medical implant according to claim 3, characterized in that: The recovery portion includes a plurality of bases, which are arranged at intervals around the axis of the core shaft, and each of the bases is provided with the feeler.

6. The pushing core wire of the medical implant according to claim 5, characterized in that The recovery part further includes an annular connector, and the proximal end of the base is arranged on the annular connector and connected to the sleeve through the annular connector.

7. The pushing core wire of the medical implant according to claim 6, characterized in that: The annular connecting piece is arranged on the tube body, or the annular connecting piece is arranged on the distal end surface of the pushing block.

8. The pushing core wire of the medical implant according to claim 1, characterized in that The support portion includes a first wedge-shaped segment, wherein a distance between an outer surface of the first wedge-shaped segment and a side wall of the core shaft gradually increases from a proximal end to a distal end; When the pushing core wire is in the first state, the first wedge segment is at least partially located on the distal side of the recovery portion; when the recovery component is in the second state, the first wedge segment is at least partially located between the recovery portion and the core shaft.

9. A medical device, characterized in that: include: sheath; The push core wire of the medical implant according to any one of claims 1 to 8, wherein the push core wire is partially disposed in the sheath tube and is movable along the axial direction of the sheath tube; as well as, A medical implant is compressed in the sheath tube and sleeved on the outer surface of the pushing core wire and located at the distal end of the pushing block; The medical device is configured such that, when the retrieval component is in the first state, the pushing block is used to abut against the proximal end of the medical implant; and when the retrieval component is in the second state, the retrieval portion is at least partially pressed against the inner surface of the medical implant or inserted into the pore of the medical implant.

10. The medical device according to claim 9, characterized in that The medical implant is a medical stent.

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