A stent restenosis treatment device

Abstract

The utility model discloses a kind of reinstallation devices after windowing of film-covered stent in vitro, stent system includes mandrel tube, handle assembly, outer sheath, film-covered stent, fixator and receiver, and the film-covered stent after release can be hung on fixator and can be separated from fixator;Reinstallation device includes pull wire for pulling the overall movement of stent system by passing through mandrel tube and handle assembly, converging device for exerting the clamping force of radial inward to fixator, loading tube and loading tool for loading the film-covered stent after windowing into outer sheath, and breaker for cutting loading tube.This kind of reinstallation device, in the process of film-covered stent reinstallation, converging device can prevent fixator from deforming, and film-covered stent after windowing is pulled into loading tube and outer sheath by loading tool, not easy to cause damage to film-covered stent, pull wire can pull film-covered stent into outer sheath with straight path, and the position of film-covered stent after windowing is not easy to change after reinstallation.

Description

Technical Field

[0001] This utility model relates to the field of interventional medical device technology, specifically to a reinstallation device for a covered stent after external fenestration of the aortic arch. Background Technology

[0002] Minimally invasive treatment of diseases involving the aortic arch is a new approach to aortic disease management. Currently, multi-branch endovascular reconstruction of the aortic arch is commonly used for this minimally invasive treatment. This technique primarily utilizes a stent delivery system to deliver an aortic endovascular stent graft to the location of the diseased aortic arch. The stent graft is then supported within the diseased aortic arch, creating a new blood flow pathway and thus achieving the therapeutic goal.

[0003] However, because the aortic arch has many branch arteries (including the brachiocephalic trunk, left common carotid artery, left subclavian artery, and variant vertebral artery and aberrant right subclavian artery), placing an aortic endovascular stent graft in the aortic arch will block the blood supply to these branch arteries. These branch arteries are responsible for supplying blood to the brain and upper limbs. If the blood supply to the brain is blocked for more than five minutes, it will cause severe irreversible brain damage due to hypoxia, and may even lead to the patient's death. Therefore, it is necessary to create a window at the location of the branch artery corresponding to the aortic endovascular stent graft to ensure the normal blood flow to the branch artery.

[0004] Because the number, diameter, spacing, location, and direction of the branch arteries on the aortic arch vary from person to person without any obvious regularity, it is impossible to solve the blood supply problem of the molecular arteries by pre-fabricating fenestrations on the aortic stent graft. Currently, in-situ fenestration technology and fenestration technology are generally used to solve this problem.

[0005] In situ fenestration is a technique that involves implanting an aortic endovascular stent graft into the aortic arch, then performing an in situ fenestration based on the location of the branch arteries above the aortic arch, and finally implanting a branch artery endovascular stent graft at the fenestration site.

[0006] However, the timing of in-situ fenestration is difficult to control. If the in-situ fenestration surgery takes more than 5 minutes, it can cause intracranial ischemia, leading to irreversible damage or even death. Therefore, it is difficult to promote its widespread application.

[0007] The extracorporeal fenestration technique involves first obtaining the number and location of the branch arteries on the patient's aortic arch, then 3D printing a model of the patient's aortic arch and branch arteries outside the body. The aortic endovascular stent graft is then implanted into the model for marking and fenestration. Next, the fenestrated aortic endovascular stent graft is reloaded into the delivery sheath of the stent delivery system, which then implants the fenestrated aortic endovascular stent graft into the patient's aortic arch. The entire process eliminates the need for fenestration of the aortic endovascular stent graft inside the body, resulting in better surgical safety.

[0008] However, in existing technologies, fenestrated covered stents are manually reinstalled into the delivery sheath. The manual reinstallation method is as follows: one assistant uses a thread to tie the distal end of the deployed covered stent and retracts it; another assistant rotates the handle and pushes the delivery sheath forward; the operator manually inserts the covered stent into the delivery sheath to complete the reinstallation. This method requires close coordination between the operator and two assistants. During the reinstallation process, the covered stent is prone to twisting or axial compression. The retracted shape of the reinstalled covered stent differs from its original shape, altering its release performance. After delivery to the posterolateral aspect of the aortic arch, the fenestrated position on the covered stent may not correspond to the location of the branch arteries. Therefore, achieving successful reinstallation of the covered stent after external fenestration, ensuring that the reinstalled stent's condition matches the original product, is a pressing problem that needs to be solved. Utility Model Content

[0009] In view of this, the purpose of this utility model is to provide a reinstallation device for a covered stent after external venous opening, so as to solve the problems of difficulty in external reinstallation of existing covered stents, easy deformation or damage of the covered stent during the rotation process, and difficulty in ensuring that the retracted shape of the covered stent after reinstallation is consistent with the original shape.

[0010] To solve the above-mentioned technical problems, the technical solution of this utility model is as follows:

[0011] A reinstallation device for a covered stent after external fenestration, the device being used to reinstall the covered stent after external fenestration into the outer sheath of the stent system, the stent system comprising:

[0012] A mandrel tube with a handle assembly at its proximal end;

[0013] An outer sheath is fitted around the outer periphery of the mandrel tube and its proximal end is detachably connected to the handle assembly.

[0014] The covered stent is a self-expanding structure, having a retracted state housed within the outer sheath and an expanded state that extends radially outward after the outer sheath is withdrawn; the distal end of the covered stent has a bare stent section.

[0015] A retainer is movably sleeved on the mandrel tube and located at the distal end of the covered support; the distal end of the covered support is hung on the retainer, and when the covered support is in an unfolded state and the retainer moves towards the proximal end, the distal end of the covered support can detach from the retainer.

[0016] The reloading device includes:

[0017] A pull wire, the proximal end of which is fixed to the handle assembly or mandrel tube of the support system, and the distal end of which extends outward from the distal opening of the mandrel tube; the pull wire is used to pull the overall movement of the mandrel tube, the fixator and the covered support.

[0018] The loading fixture has a conical cavity with a large proximal opening and a small distal opening; the distal end of the loading fixture is detachably connected to the proximal end of the outer sheath tube, and the loading fixture is used to guide the retainer and the film-coated support on the mandrel tube into the interior of the outer sheath tube.

[0019] Furthermore, the reloading device also includes a loading pipe and a breaker;

[0020] The distal end of the loading fixture can also be detachably connected to the proximal end of the loading tube. When the loading fixture is connected to the proximal end of the loading tube, the loading tube is used to guide the retainer on the mandrel tube and the film-coated support into the interior of the loading tube. When the loading fixture is connected to the proximal end of the outer sheath tube, the loading fixture is used to guide the retainer and film-coated support inside the loading tube into the interior of the outer sheath tube.

[0021] The splitter is used to cut the loading tube after the fixator and the covering support are inserted into the outer sheath, so that the proximal end of the outer sheath is connected to the handle assembly.

[0022] Furthermore, a tapered head is fixed to the distal end of the mandrel tube, and the support system also includes a receiver, which is fixedly connected to the proximal end of the tapered head and located at the distal end of the retainer. The proximal end of the receiver is provided with a receiving hole, into which the retainer can be inserted. The reassembly device also includes a convergent force, which is used to apply a radially inward force to the retainer so that the retainer can be inserted into the receiving hole after being retracted.

[0023] Furthermore, the reinstallation device also includes a protective sleeve, which is used to cover the outer periphery of the distal opening of the outer sheath before the film-coated support is released from the distal end of the outer sheath, so as to prevent the distal end of the outer sheath from deforming; the reinstallation device also includes a clamp, which is used to clamp the pull wire and pull the pull wire to move.

[0024] Furthermore, the pull line is provided with a pull line limiter, which is fixed to the mandrel tube of the support system or its handle assembly or conical head.

[0025] Furthermore, the handle assembly includes a pull cable handle and a tail end connector fixed to the proximal end of the pull cable handle, the pull cable limiter is connected to the distal end of the pull cable and the pull cable limiter is fixed to the tail end connector; or, the pull cable limiter is connected to the proximal end of the pull cable and the pull cable limiter is fixed to the tapered head at the distal end of the mandrel tube.

[0026] Furthermore, the distal end of the handle assembly is provided with a locking connector, and the proximal end of the outer sheath is detachably connected to the locking connector.

[0027] This utility model's technical solution has the following advantages: During the reinstallation of the covered stent, a loading fixture with a conical cavity having a large proximal opening and a small distal opening is detachably connected to the proximal end of the outer sheath. The overall movement of the mandrel tube, retainer, and covered stent, facilitated by a pull cable, allows the retainer and covered stent on the mandrel tube to be smoothly pulled into the outer sheath tube, reducing damage to the proximal opening of the outer sheath tube during reinstallation. Furthermore, the convergent clamp prevents the retaining pin on the retainer from flipping outwards, facilitating smooth insertion of the retainer into the receiver's receiving port. The method of first inserting the covered stent into the loading tube and then into the outer sheath tube after the window is opened further reduces damage to the covered stent. The entire re-implantation process only requires a suture, a loading tool, and a loading tube to pull the fenestrated covered stent into the outer sheath. The matching rupture device then cuts open the loading tube. The re-implantation device has a simple structure and the re-implantation method is convenient to operate. During the re-implantation process, the covered stent can be pulled into the outer sheath in a straight path using a suture. After re-implantation, the fenestrated covered stent is less prone to torsion or axial compression. The retraction shape of the fenestrated covered stent after re-implantation can be the same as the original shape of the unfenestrated covered stent pre-installed in the stent system. The release performance of the fenestrated covered stent does not change. After the fenestrated covered stent is delivered to the posterolateral aspect of the aortic arch for release, there is less likelihood of a mismatch between the fenestration position on the covered stent and the branch artery position, which is beneficial for the smooth progress of subsequent endovascular stent graft isolation surgery. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of the unwindowed film-covered support portion of the present invention being released outward from the distal end of the outer sheath in Embodiment 1 of the present invention;

[0030] Figure 2This is a schematic diagram of the structure of the film-covered bracket after the window is opened in Embodiment 1 of this utility model, with the bare bracket section of the bracket hanging on the fixer and the convergent clamped outside the fixer.

[0031] Figure 3 This is a schematic diagram of the structure of the bare bracket section of the film-coated bracket after the window is opened in Embodiment 1 of this utility model, with the bracket hanging on the fixer and the fixer inserted into the receiver.

[0032] Figure 4 This is a schematic diagram of the structure of the film-covered bracket after the window is opened in Embodiment 1 of this utility model when it is loaded into the loading tube by the loading tool;

[0033] Figure 5 This is a schematic diagram of the structure of the film-coated support with the window opened in the loading tube in Embodiment 1 of this utility model when it is loaded into the outer sheath tube by the loading tool;

[0034] Figure 6 This is a schematic diagram of the structure of the cutter cutting the loading tube in Embodiment 1 of this utility model;

[0035] Figure 7 This is a schematic diagram of the support system after the film-covered support is reinstalled following the opening of the window in Embodiment 1 of this utility model;

[0036] Figure 8 This is a schematic diagram of the structure of the film-covered bracket after the window is opened in Embodiment 2 of this utility model when it is loaded into the loading tube by the loading tool;

[0037] Figure 9 This is a schematic diagram of the support system after the film-covered support is reinstalled following the opening of the window in Embodiment 2 of this utility model.

[0038] Explanation of reference numerals in the attached drawings: A01, pull line; A02, protective sleeve; A03, pull line limiter; A04, convergent device; A05, clamp; A06, loading tube; A07, loading tool; A08, splitter; B01, conical head; B02, film-covered support without window opening; B03, outer sheath; B04, pull line handle; B05, tail connector; B06, conveying handle; B07, fixing handle; B08, locking connector; B09, receiver; B10, fixing device; B11, guide; B12, film-covered support after window opening; B13, mandrel tube. Detailed Implementation

[0039] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0040] In the description of this application, it should be understood that the terms "proximal" and "distal" throughout refer to near and far relative to the operator. In use, the end closer to the doctor or operator is the "proximal" end, i.e., the end where the operator is located, and the end farther from the doctor or operator is the "distal" end. The above descriptions of orientation are merely for the convenience of describing this application and for simplification, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this application.

[0041] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0042] Endovascular aortic repair is a minimally invasive endovascular treatment technique that involves inserting a covered stent into the diseased area of ​​the aorta through a femoral artery incision to repair the aortic lesion from within the arterial lumen, thus avoiding open surgery. Compared with traditional surgery, endovascular aortic repair significantly reduces surgical trauma, shortens operation time, and reduces surgical complications and mortality.

[0043] External fenestration of the endovascular stent graft is primarily used to treat aortic aneurysms or aortic dissections located in the aortic arch. The greatest challenge of endovascular treatment is preserving blood flow to vital branches of the aortic arch while simultaneously isolating the aorta and the dissection site. Therefore, fenestration is performed at the corresponding location on the endovascular stent graft before implantation, based on the number and location of the branch arteries in the aortic arch.

[0044] However, in existing technologies, the fenestrated covered stents are manually reinstalled into the stent system's delivery sheath. This reinstallation process can easily cause the covered stent to twist or be axially compressed, resulting in a different retracted shape compared to its original form. This alters the stent's release performance, and after delivery to the posterolateral aspect of the aortic arch, the fenestration position on the stent may not correspond to the location of the branch arteries. Therefore, achieving successful reinstallation of the covered stent after in vitro fenestration, ensuring that the reinstalled stent maintains the same condition as the original product, is a pressing challenge that needs to be addressed.

[0045] To address the aforementioned problems, this invention provides a reinstallation device for a covered stent after external fenestration. This reinstallation device is used to reinstall the covered stent B12 after external fenestration into the outer sheath B03 of the stent system. To distinguish between the reinstallation device and the stent system, components containing the code A are designated as reinstallation device components, and components containing the code B are designated as stent system components.

[0046] Example 1

[0047] like Figure 1 - Figure 7 As shown, the support system includes a mandrel tube B13, a handle assembly, an outer sheath tube B03, a covered support, a retainer B10, and a receiver B09.

[0048] In some embodiments, the mandrel tube B13 is a longitudinally extending tubular structure, and a tapered head B01 is fixed to the distal end of the mandrel tube B13. The handle assembly includes a pull handle B04, a delivery handle B06, and a fixed handle B07 connected sequentially from proximal to distal end. The fixed handle B07 is detachably connected to the distal end of the delivery handle B06, and the pull handle B04 is connected to the proximal end of the delivery handle B06; the delivery handle B06 is fixedly connected to the proximal end of the mandrel tube B13. The outer sheath tube B03 is sleeved on the outer periphery of the mandrel tube B13, and a locking connector B08 is provided at the distal end of the delivery handle B06. The proximal end of the outer sheath tube B03 is detachably connected to the locking connector B08. The covered support is a self-expanding structure, having a retracted state housed within the outer sheath tube B03 and an expanded state radially outward after the outer sheath tube B03 is withdrawn; the distal end of the covered support has a bare support section. For ease of description, the covered support before and after the window is opened are referred to as the covered support without the window, B02, and the covered support after the window is opened, respectively.

[0049] The fixator B10 is movably sleeved on the mandrel tube B13, and is located at the distal end of the covered stent. The fixator B10 can specifically employ a mechanical locking or collar structure. A pull rope is connected to the proximal end of the fixator B10 for pulling the fixator B10 axially along the mandrel tube B13. The bare stent segment at the distal end of the covered stent is suspended on the fixator B10. When the covered stent is released and unfolded in the body, the pull rope pulls the fixator B10 proximally, allowing the bare stent segment at the distal end of the covered stent to detach from the fixator B10. This allows the covered stent to be implanted at the appropriate position in the body, and the mandrel tube B13 and fixator B10 of the stent system can be withdrawn. In some embodiments, the end of the bare stent segment is temporarily connected to the fixator B10 via barbs, protrusions, or elastic arms. This design allows the covered stent and fixator to remain connected during the initial release phase, while creating conditions for subsequent detachment. When the outer sheath B03 is withdrawn externally, the covered stent self-expands, and the bare stent segment at the distal end of the covered stent is hooked onto the fixator B10. The covered stent and the fixator B10 remain connected, facilitating subsequent reinstallation of the covered stent. When the outer sheath B03 is withdrawn externally, the covered stent self-expands internally, and the bare stent segment at the distal end of the covered stent is hooked onto the fixator B10. After the covered stent is released internally, the fixator B10 is pulled proximally using a pull cord. At this point, the bare stent segment at the distal end of the covered stent and the fixator B10 detach, making it easier to remove the mandrel B13 and the fixator B10 from the body.

[0050] In some embodiments of this example, the receiver B09 is located at the distal end of the retainer B10, and the receiver B09 is fixed to the proximal end of the conical head B01, or the receiver B09 and the conical head B01 are an integral structure, with a receiving hole provided at the proximal end of the receiver B09, into which the retainer B10 can be inserted. In other alternative embodiments, the receiver B09 of the support system can be omitted.

[0051] In some embodiments of this example, the reloading device includes a pull wire A01 and a loading fixture A07, wherein the pull wire A01 is specifically a steel wire. The pull wire A01 passes through the entire support system consisting of the mandrel tube B13 and the handle assembly. The proximal end of the pull wire A01 is fixed to the pull wire handle B04, and the distal end of the pull wire A01 extends outward from the distal opening of the mandrel tube B13. The pull wire A01 is used to pull the entire assembly formed by the mandrel tube B13, the retainer B10, and the film-covered support B12 after the window is opened, moving it in a straight line. In other alternative embodiments, the proximal end of the pull wire A01 can also be directly fixed to the conical head B01.

[0052] In some embodiments of this invention, the reassembly device further includes a convergent assembly A04, which has a scissor-like structure similar to pliers. One end of the convergent assembly A04 is an operating end, and the other end is a convergent end. The convergent end is closed together in its natural state, and can be opened by gripping the operating end. In this application, the convergent end of the convergent assembly A04 is clamped to the outside of the retainer B10. The convergent assembly A04 applies a radially inward force to the retainer B10 to prevent the fixing pin on the retainer B10 from being radially stretched outward or even folded under the radial expansion force of the bare bracket section, thus protecting the retainer B10 from deformation and facilitating the smooth pushing of the retainer B10 into the receiver B09.

[0053] In some embodiments of this example, the reloading device further includes a loading tube A06 and a splitter A08. Both the loading tube A06 and the loading fixture A07 can be fitted onto the pull wire A01. The loading tube A06 is a long tube and can be cut open by the splitter A08. The loading fixture A07 is conical, and its interior has a conical cavity with a larger opening at the proximal end and a smaller opening at the distal end. The distal end of the loading fixture A07 is detachably connected to the proximal end of the loading tube A06, and the distal end of the loading fixture A07 can also be detachably connected to the proximal end of the outer sheath B03. During the external reloading of the covered stent, when loading fixture A07 is connected to the proximal end of loading tube A06, loading fixture A07 guides the conical head B01, retainer B10, and the fenestrated covered stent B12 into the interior of loading tube A06; when loading fixture A07 is connected to the proximal end of outer sheath tube B03, loading fixture A07 guides the retainer B10 and the fenestrated covered stent B12 inside loading tube A06 into the interior of outer sheath tube B03. Breaker A08 is used to cut loading tube A06 after retainer B10 and the fenestrated covered stent B12 have been loaded into outer sheath tube B03, so that the proximal end of outer sheath tube B03 is connected to the locking joint B08 of delivery handle B06. After the fenestrated covered stent B12 is opened, it is pulled into the loading tube A06 and outer sheath B03 by the loading fixture A07, which minimizes the risk of damage to the fenestrated covered stent B12. The method of first loading the fenestrated covered stent B12 into the loading tube A06 and then into the outer sheath B03 further reduces damage to the fenestrated covered stent B12. Moreover, the loading fixture A07 can be reused, reducing the complexity of the reinstallation device. In alternative embodiments, the loading tube A06 and the breaker A08 can be omitted. During the external reinstallation of the covered stent, the distal end of the loading fixture A07 is directly connected to the proximal end of the outer sheath B03, and the loading fixture A07 guides the conical head B01, the retainer B10, and the fenestrated covered stent B12 directly into the interior of the outer sheath B03.

[0054] In some embodiments of this example, the reinstallation device further includes a clamp A01 and a protective sleeve A02. The clamp A01 is used to clamp the pull wire A01 and pull the pull wire A01 to move. The protective sleeve A02 is used to be fitted around the outer periphery of the distal opening of the outer sheath B03 before the film-coated support is released from the distal end of the outer sheath B03, so as to prevent the distal end of the outer sheath B03 from deforming.

[0055] In some embodiments of this example, the reinstallation device further includes a pull-line limiter A03 fixedly connected to the proximal end of the pull line A01, and a tail end connector B05 fixed to the proximal end of the pull line handle B04, with the pull-line limiter A03 fixed to the tail end connector B05. The pull-line limiter A03 facilitates pulling the covered bracket into the outer sheath tube B03 along a straight path via the pull line A01, making it less likely for the covered bracket B12 to twist or be axially compressed after reinstallation.

[0056] This retrieval device for fenestrated covered stents only requires pulling the fenestrated covered stent B12 into the outer sheath B03 using a pull wire A01, loading tool A07, and loading tube A06. The matching breaker A08 then cuts the loading tube A06. The reinstallation device has a simple structure. During the reinstallation process, the covered stent can be pulled into the outer sheath B03 in a straight path using the pull wire A01. After reinstallation, the fenestrated covered stent B12 is less prone to torsion or axial compression. The retraction shape of the fenestrated covered stent B12 after reinstallation can be the same as the original shape of the pre-installed unfenestrated covered stent B02 in the stent system. The release performance of the fenestrated covered stent B12 will not change. After the fenestrated covered stent B12 is delivered to the aortic arch for release, the problem of mismatch between the fenestration position on the fenestrated covered stent B12 and the branch artery position is less likely to occur, which is conducive to the smooth performance of subsequent endovascular stent graft isolation surgery.

[0057] This application also provides a method for recovering a covered stent after in vitro fenestration, the method being used to re-insert the covered stent B12 after in vitro fenestration into the outer sheath B03 of the stent system. In some embodiments, the recovery method includes the following steps:

[0058] Step S1: Using the pull wire A01, pass through the mandrel tube B13 and handle assembly of the support system to remove the outer sheath tube B03 from the support system. At this time, the bare support segment at the distal end of the film-coated support B12 after the window is opened is hung on the fixator B10. Then, using the convergent device A04, clamp the outside of the fixator B10 and push the fixator B10 towards the distal end so that the fixator B10 is inserted into the receiving hole of the receiver B09.

[0059] Step S21: Place the loading tube A06 and loading fixture A07 onto the pull line A01, connect the loading fixture A07 to the proximal end of the loading tube A06, and fix the proximal end of the pull line A01 to the handle assembly; keep the overall position formed by the loading tube A06 and loading fixture A07 unchanged, pull the pull line A01 to the distal end, and the pull line A01 drives the entire support system to move relative to the loading tube A06 and loading fixture A07. The film-covered support B12 after the window is opened is pulled into the loading tube A06 through the loading fixture A07, and finally remove the loading fixture A07 from the loading tube A06.

[0060] Step S22: Place the outer sheath tube B03 onto the pull line A01, and connect the removed loading fixture A07 to the proximal end of the outer sheath tube B03; keeping the overall position formed by the loading tube A06 and the loading fixture A07 unchanged, pull the pull line A01 to the distal end. The pull line A01 drives the entire support system to move relative to the outer sheath tube B03 and the loading fixture A07. The film-coated support B12 with the window opened in the loading tube A06 is inserted into the outer sheath tube B03 through the loading fixture A07; use the cutter A08 to cut open the loading tube A06 and remove it.

[0061] Step S3: Remove the loading fixture A07 from the proximal end of the outer sheath B03, pull the pull cable A01 to bring the proximal end of the outer sheath B03 close to the handle assembly, and lock the proximal end of the outer sheath B03 onto the handle assembly to complete the assembly.

[0062] In an alternative implementation, during the external reloading of the covered stent, the loading tube A06 and the rupture device A08 can be omitted. The distal end of the loading fixture A07 can be directly connected to the proximal end of the outer sheath B03. The overall position formed by the outer sheath B03 and the loading fixture A07 remains unchanged. The pull wire A01 is pulled to the distal end. The pull wire A01 drives the entire stent system to move relative to the outer sheath B03 and the loading fixture A07. After the fenestration, the covered stent B12 is pulled into the outer sheath B03 through the loading fixture A07.

[0063] In some embodiments, before step S1, step S0 is included: before the handle assembly releases the unopened film-coated support B02 from the outer sheath B03, a protective sleeve A02 is fitted over the outer periphery of the distal opening of the outer sheath B03, the protective sleeve A02 preventing proximal deformation of the outer sheath B03. After steps S1 and S21, the method further includes: using a convergent clamp A04 to hold the outside of the retainer B10, and pushing the retainer B10 distally, so that the retainer B10 is inserted into the receiving hole of the receiver B09. In steps S2 and S3, a clamp A05 is used to clamp the pull wire A01 to move the pull wire A01.

[0064] During the external reinstallation of the covered stent, a loading fixture A07 with a conical cavity having a larger proximal opening and a smaller distal opening is detachably connected to the proximal end of the outer sheath A03. The mandrel tube B13, retainer B10, and the fenestrated covered stent B12 are pulled together by a pull cable A01, facilitating the smooth insertion of the retainer B10 on the mandrel tube B13 and the fenestrated covered stent B12 into the outer sheath A03. This reduces damage to the proximal opening of the outer sheath A03 during the reinstallation of the fenestrated covered stent B12. Furthermore, the convergent device A04 can clamp and prevent deformation of the retainer B10, preventing the retaining pin on the retainer B10 from flipping outwards, and facilitating the smooth insertion of the retainer B10 into the receiving hole of the receiver B09. The fenestrated covered stent B12 is pulled into the loading tube A06 and outer sheath B03 by the loading fixture A07, minimizing the risk of damage to the fenestrated covered stent B12. The method of first inserting the film-covered bracket B12 into the loading tube A06 and then into the outer sheath tube B03 after the window is opened can further reduce the damage to the film-covered bracket B12 after the window is opened. The entire reinstallation process only requires the pull wire A01, loading tool A07, and loading tube A06 to pull the fenestrated covered stent B12 into the outer sheath B03. The matching rupture device A08 then cuts the loading tube A06. The reinstallation device has a simple structure and the reinstallation method is convenient to operate. During the reinstallation process, the pull wire A01 can pull the fenestrated covered stent B12 into the outer sheath B03 in a straight path. After reinstallation, the fenestrated covered stent B12 is not prone to torsion or axial compression. The retraction shape of the fenestrated covered stent B12 after reinstallation can be the same as the original shape of the pre-installed unfenestrated covered stent B02 in the stent system. The release performance of the fenestrated covered stent B12 will not change. After the fenestrated covered stent B12 is delivered to the aortic arch for release, the problem of mismatch between the fenestration position on the fenestrated covered stent B12 and the branch artery position is not likely to occur, which is conducive to the smooth performance of subsequent endovascular stent graft isolation surgery.

[0065] Example 2

[0066] Embodiment 2 of this utility model provides a recovery device for a covered stent after external fenestration, such as... Figure 8 and Figure 9 As shown, the overall structure and working principle of the reassembly device in Embodiment 2 are basically the same as those in Embodiment 1. The difference between the recycling method and Embodiment 1 is that before reassembling the film-coated bracket B12 after opening the window, a branch bracket is sewn at the opening position of the film-coated bracket B12 after opening the window. Since the setting of the branch bracket will increase the cross-sectional area of ​​the bracket after compression, a larger sheath tube B14 is selected for assembly in order to protect the bracket from damage.

[0067] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A reinstallation device for a covered stent after external fenestration, characterized in that, The reloading device is used to reload the covered stent (B12) after external fenestration into the outer sheath (B03) of the stent system, the stent system comprising: The mandrel tube (B13) has a handle assembly at its proximal end; The outer sheath (B03) is sleeved on the outer periphery of the mandrel tube (B13) and its proximal end is detachably connected to the handle assembly; The covered stent is a self-expanding structure, having a retracted state housed within the outer sheath (BO3) and an extended state that expands radially outward after the outer sheath (BO3) is withdrawn; The retainer (B10) is movably sleeved on the mandrel tube (B13) and located at the distal end of the covered support; the distal end of the covered support is hung on the retainer (B10), and when the covered support is in the unfolded state and the retainer (B10) moves to the proximal end, the distal end of the covered support can detach from the retainer (B10). The reloading device includes: A pull wire (A01), the proximal end of which is fixed to the support system; the pull wire (A01) is used to pull the support system to move; The loading fixture (A07) has a conical cavity with a large proximal opening and a small distal opening; the distal end of the loading fixture (A07) is detachably connected to the proximal end of the outer sheath (B03), and the loading fixture (A07) is used to guide the retainer (B10) and the coating support on the mandrel tube (B13) into the interior of the outer sheath (B03).

2. The reinstallation device for the covered stent after external fenestration according to claim 1, characterized in that, The reloading device also includes a loading pipe (A06) and a breaker (A08); The distal end of the loading fixture (A07) can also be detachably connected to the proximal end of the loading tube (A06). When the loading fixture (A07) is connected to the proximal end of the loading tube (A06), the loading tube (A06) is used to guide the retainer (B10) and the coating support on the mandrel tube (B13) into the interior of the loading tube (A06). When the loading fixture (A07) is connected to the proximal end of the outer sheath tube (B03), the loading fixture (A07) is used to guide the retainer (B10) and the coating support inside the loading tube (A06) into the interior of the outer sheath tube (B03). The cutter (A08) is used to cut the loading tube (A06) after the fixer (B10) and the covering bracket are inserted into the outer sheath (B03) so that the proximal end of the outer sheath (B03) is connected to the handle assembly.

3. The reinstallation device for the covered stent after external fenestration according to claim 1, characterized in that, The distal end of the mandrel tube (B13) is fixed with a conical head (B01). The support system also includes a receiver (B09), which is fixedly connected to the proximal end of the conical head (B01) and located at the distal end of the retainer (B10). The proximal end of the receiver (B09) is provided with a receiving hole, into which the retainer (B10) can be inserted. The reassembly device also includes a convergent member (A04), which is used to apply a radially inward force to the retainer (B10) so that the retainer (B10) can be inserted into the receiving hole after it is retracted.

4. The reinstallation device for the covered stent after external fenestration according to claim 1, characterized in that, The reinstallation device also includes a protective sleeve (A02), which is used to cover the outer periphery of the distal opening of the outer sheath (B03) before the film-coated support is released from the distal end of the outer sheath (B03) to prevent deformation of the distal end of the outer sheath (B03).

5. The reinstallation device for the covered stent after external fenestration according to claim 1, characterized in that, The reloading device also includes a clamp (A05) for clamping the pull wire (A01) and pulling the pull wire (A01) to move.

6. The reinstallation device for the covered stent after external fenestration according to claim 1, characterized in that, The pull wire (A01) is provided with a pull wire limiter (A03), which is fixed to the mandrel tube (B13) of the support system or its handle assembly or conical head (B01).

7. The reinstallation device for the covered stent after external fenestration according to claim 6, characterized in that, The handle assembly includes a pull cable handle (B04) and a tail connector (B05) fixed to the proximal end of the pull cable handle (B04), wherein a pull cable limiter (A03) is connected to the proximal end of the pull cable (A01) and the pull cable limiter (A03) is fixed to the tail connector (B05); or, The pull wire limiter (A03) is connected to the far end of the pull wire (A01), and the pull wire limiter (A03) is fixed on the tapered head (B01) at the far end of the mandrel tube (B13).

8. The reinstallation device for the covered stent after external fenestration according to claim 1, characterized in that, The distal end of the handle assembly is provided with a locking connector (B08), and the proximal end of the outer sheath (B03) is detachably connected to the locking connector (B08).

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