Blood vessel covered stent and conveying device

Abstract

The utility model relates to the technical field of medical instruments, and provides a blood vessel covered stent and a conveying device.The blood vessel covered stent comprises a body, and the body is divided into a stent far end, a stent middle section and a stent near end in the axial direction of the body; the body comprises an inner film, a bare metal frame and an outer film from inside to outside in the radial direction of the body; along the axial direction of the bare metal frame, the bare metal frame is composed of a plurality of connected waveform rings, and each waveform ring is of a waveform structure with a wave crest and a wave trough. Wherein the outer membrane located at the middle section of the stent incompletely covers the wave-shaped rings, so that the wave crests and the wave troughs of the wave-shaped rings are exposed. According to the blood vessel covered stent, the bending performance of the whole blood vessel covered stent is better, the original basic cross sectional area of an inner cavity can be kept unchanged when the blood vessel covered stent is bent and twisted in a limited mode, and when blood flows through the blood vessel covered stent, resistance is small, the blood vessel covered stent is not prone to being narrow and high in patency rate.

Description

TECHNICAL FIELD

[0001] The utility model relates to medical instrument technical field, concretely relates to a blood vessel covered stent and conveying device. BACKGROUND

[0002] The current covered stent is usually sewn or laminated by an inner membrane, a metal frame connected between the inner membrane and an outer membrane and the outer membrane. However, the existing covered stent has poor bending performance, and the stent cannot well keep the original basic cross-sectional area unchanged when bending, twisting or torsion occurs. For example, the stent may be folded, causing the inner cavity through which blood flows to suddenly become a very narrow gap, which is prone to stenosis or even occlusion, and finally causes large resistance to blood flow and low patency rate. SUMMARY

[0003] Therefore, the technical problem to be solved by the utility model is to provide a blood vessel covered stent and conveying device to solve the poor bending performance of the covered stent in the prior art.

[0004] To solve the above technical problems, the technical scheme of the utility model is as follows:

[0005] On the one hand, the utility model provides a blood vessel covered stent, which comprises a body, the body is divided into a stent distal end, a stent middle section and a stent proximal end along the axial direction of the body, the body comprises an inner membrane, a bare metal frame and an outer membrane along the radial direction of the body from inside to outside, the bare metal frame is composed of a plurality of connected wave-shaped rings along the axial direction of the bare metal frame, each wave-shaped ring is a wave-shaped structure comprising a wave crest and a wave trough, and the outer membrane in the stent middle section incompletely covers each wave-shaped ring so that the wave crest and the wave trough of each wave-shaped ring are exposed.

[0006] Further, the outer membrane at the stent proximal end and the stent distal end fully covers each wave-shaped ring, and the inner membrane at the two end portions of the bare metal frame is connected to the outer membrane through the bare metal frame to wrap the bare metal frame.

[0007] Further, the adjacent two wave-shaped rings in the stent middle section are arranged equidistantly and at least partially overlapped, and the overlapping distance is recorded as L1; the adjacent two wave-shaped rings at the stent proximal end and the stent distal end are arranged at least partially overlapped, and the minimum overlapping distance is recorded as L2, and L2 is greater than L1.

[0008] Further, the end profile of the stent distal end is wave-shaped or flower-shaped.

[0009] Further, the inner side wall of the inner membrane is provided with an anticoagulant coating.

[0010] Further, each end face of the two end portions of the bare metal frame is flushly arranged.

[0011] Further, the vascular covered stent further comprises an auxiliary membrane arranged on the outer side wall of the outer membrane; along the width direction of the auxiliary membrane, the thickness of the two side edges of the auxiliary membrane is greater than the thickness of the middle part, and along the length direction of the auxiliary membrane, the edges of the auxiliary membrane are provided with a plurality of spaced through holes.

[0012] In another aspect, the utility model also provides a conveying device for conveying the vascular covered stent, which comprises a conical head, a fixing ring, a support pipe and an outer pipe; the support pipe comprises a mandrel pipe, a single-lumen pipe, a reinforcing pipe and a stainless steel pipe; the single-lumen pipe is sleeved on the mandrel pipe; the reinforcing pipe and the stainless steel pipe are sequentially sleeved on the single-lumen pipe in the direction away from the mandrel pipe; the outer pipe is sleeved outside the support pipe, and an inner cavity for arranging the vascular covered stent is formed between the outer pipe and the mandrel pipe; the conical head is fixed at the end of the mandrel pipe away from the single-lumen pipe; the fixing ring is arranged on the mandrel pipe and close to the conical head, and is used for hooking the vascular covered stent when the outer pipe is retracted.

[0013] In another aspect, the utility model also provides a conveying device for conveying the vascular covered stent, which comprises a conical head, a fixing ring, a support pipe, an outer pipe and a deployment wire; the support pipe comprises a mandrel pipe, a double-lumen pipe, a reinforcing pipe and a stainless steel pipe; the double-lumen pipe is sleeved on the mandrel pipe through one of the pipe cavities; the reinforcing pipe and the stainless steel pipe are sequentially sleeved on the double-lumen pipe in the direction away from the mandrel pipe; the outer pipe is sleeved outside the support pipe, and an inner cavity for arranging the vascular covered stent is formed between the outer pipe and the mandrel pipe; the conical head is fixed at the end of the mandrel pipe away from the double-lumen pipe, and a hidden hole is arranged on the conical head; the fixing ring is arranged on the mandrel pipe and close to the conical head, and is used for hooking the vascular covered stent when the outer pipe is retracted; one end of the deployment wire is sequentially threaded into the through holes of the two edges of the auxiliary membrane and inserted into the hidden hole on the conical head, and the other end of the deployment wire is threaded out through the other pipe cavity of the double-lumen pipe.

[0014] Further, the conveying device further comprises an outer pipe seat, a fixing handle and a support pipe joint; the outer pipe seat and the fixing handle have threads; the outer pipe seat is threadedly engaged with the outer pipe and connected with the fixing handle; the fixing handle is used for independently unlocking / locking the outer pipe to axially slide on the support pipe; the support pipe joint is connected with the end of the stainless steel pipe away from the reinforcing pipe; the other end of the deployment wire is connected with the support pipe joint after being threaded through the other pipe cavity of the double-lumen pipe.

[0015] Further, the fixing ring is provided with a ring hook, and the edge of the distal end of the stent is provided with a hanging ear; the hanging ear is hung on the ring hook, and the ring hook is used for hooking the vascular covered stent when the outer tube is retracted, so that the distal end of the stent is still hung on the fixing ring.

[0016] The technical scheme of the utility model has the following advantages:

[0017] The outer membrane of the middle section of the stent incompletely covers the wave-shaped rings, so that the wave crests and wave troughs of the wave-shaped rings are exposed, and the bending performance of the whole vascular covered stent is better, the inner cavity can keep the original basic cross-sectional area unchanged when being bent and twisted to the limit, the resistance to blood flow is small, the stenosis is not easy to occur, and the patency rate is high. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical scheme in the specific embodiment or prior art of the utility model, the drawings needed to be used in the specific embodiment or prior art description will be briefly introduced below, and obviously, the drawings in the following description are some embodiments of the utility model, and those skilled in the art can also obtain other drawings according to the drawings without creating labor.

[0019] Figure 1 It is a schematic view of the vascular covered stent in an embodiment of the utility model;

[0020] Figure 2 It is a schematic view of the distal end of the stent of the vascular covered stent in an embodiment of the utility model;

[0021] Figure 3 It is a wave-shaped ring distribution schematic view of the vascular covered stent in an embodiment of the utility model;

[0022] Figure 4 It is a sectional schematic view of the vascular covered stent in an embodiment of the utility model;

[0023] Figure 5 It is a schematic view of the bare metal frame in the vascular covered stent in another embodiment of the utility model;

[0024] Figure 6 It is an end schematic view of the bare metal frame in the vascular covered stent in an embodiment of the utility model;

[0025] Figure 7 It is a schematic view of the vascular covered stent in another embodiment of the utility model;

[0026] Figure 8 It is a schematic view of the conveying device in an embodiment of the utility model;

[0027] Figure 9 Fig. 2 is a partial enlarged schematic view of the conveying device in one embodiment of the present application;

[0028] Figure 10 Fig. 3 is a schematic view of the conveying device in another embodiment of the present application;

[0029] Figure 11 Fig. 4 is a partial enlarged schematic view of the conveying device in another embodiment of the present application;

[0030] Figure 12 Fig. 5 is a partial enlarged schematic view of the conveying device in another embodiment of the present application;

[0031] Figure 13 Fig. 6 is a partial enlarged schematic view of the conveying device in another embodiment of the present application;

[0032] Figure 14 Fig. 7 is a schematic view of the blood vessel covered stent in one application scenario in one embodiment of the present application;

[0033] Figure 15 Fig. 8 is a schematic view of the blood vessel covered stent in another embodiment of the present application;

[0034] Figure 16 Fig. 9 is a schematic view of the blood vessel covered stent in one application scenario in another embodiment of the present application; Figure 15

[0035] Fig. 10 is a schematic view of the blood vessel covered stent in another application scenario in one embodiment of the present application; Figure 17

[0036] Fig. 11 is a schematic view of the blood vessel covered stent in another application scenario in one embodiment of the present application. Figure 18 Legend of reference signs:

[0037]

[0038] ​1, body; 2, stent distal end; 3, stent middle section; 4, stent proximal end; 5, inner membrane; 6, bare metal frame; 7, outer membrane; 8, wave ring; 9, wave crest; 10, wave trough; 11, anticoagulant coating; 12, marker; 13, attached film; 14, through hole; 15, tapered head; 16, fixing ring; 17, support tube; 18, outer tube; 19, mandrel tube; 20, single lumen tube; 21, reinforcing tube; 22, stainless steel tube; 23, outer tube seat; 24, fixed handle; 25, support tube joint; 26, double lumen tube; 27, deployment wire; 28, pull wire handle; 29, iliac branch stent; 30, iliac branch stent proximal body; 31, internal iliac branch; 32, external iliac branch; 33, arteriovenous vascular access; 34, supra-arch covered stent; 35, intercostal covered stent; 36, ear; 37, ring hook. DETAILED DESCRIPTION

[0039] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0040] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as limiting the devices or elements indicated to have a specific orientation, to be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0041] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0042] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0043] For example, Figure 1 , Figure 3As shown, the embodiment provides a vascular covered stent, comprising: a body 1, along the axial direction of the body 1, the body 1 is divided into a stent distal end 2, a stent middle section 3 and a stent proximal end 4; along the radial direction of the body 1 and from inside to outside, the body 1 comprises an inner membrane 5, a bare metal framework 6 and an outer membrane 7, for example, the width of the outer membrane 7 can be between 0.5mm-3.5mm. Along the axial direction of the bare metal framework 6, the bare metal framework 6 is composed of a plurality of connected wave-shaped rings 8, each of the wave-shaped rings 8 is a wave-shaped structure containing a wave crest 9 and a wave trough 10, for example, the protrusion close to the stent proximal end 4 can be called the wave trough 10, and the protrusion close to the stent distal end 2 can be called the wave crest 9; wherein the outer membrane 7 located in the stent middle section 3 does not completely cover each wave-shaped ring 8, so that the wave crest 9 and the wave trough 10 of each wave-shaped ring 8 are exposed.

[0044] The vascular covered stent provided by the embodiment, the outer membrane 7 located in the stent middle section 3 does not completely cover each wave-shaped ring 8, so that the wave crest 9 and the wave trough 10 of each wave-shaped ring 8 are exposed, so arranged, compared with the stent with an overall covering membrane in the prior art, since the covering membrane is an overall membrane, the bending capacity of the bending part is not strong, which will make the bending part bear too much stress and bend; the stent provided by the utility model is covered by a strip-shaped covering membrane, when bending, the stress of the bending part is distributed to the entire covering membrane, so that the bending performance of the entire vascular covered stent is better, when bending to the limit and twisting, the inner cavity can maintain the original basic cross-sectional area unchanged, the resistance to blood flow is small, it is not easy to narrow, and the patency rate is high.

[0045] Wherein, the outer membrane 7 located at the stent proximal end 4 and the stent distal end 2 completely covers each wave-shaped ring 8; the inner membrane 5 at the two end portions of the bare metal framework 6 is connected with the outer membrane 7 through the bare metal framework 6, so as to wrap the bare metal framework 6 inside. Since the inner membrane 5, the bare metal framework 6 and the outer membrane 7 are stacked one by one from inside to outside, separation between the layers is easy to occur at the port, therefore, the inner membrane 5 can be left long to cover the bare metal framework 6 and the outer membrane 7 upward. So arranged, the contact surface of the inner membrane 5 with the bare metal framework 6 and the outer membrane 7 can be increased, the inner membrane 5 and the outer membrane 7 are simultaneously adhered on the upper and lower surfaces, so that the covering membrane has higher bonding strength and is not easy to separate between the layers. At the same time, since it is at the port, it may be subjected to more violent blood flow in the blood vessel; when the stent is assembled, the probability of damage to the port is greater, therefore, the stent is not easy to be damaged when the covering membrane has greater bonding strength.

[0046] Wherein, the adjacent two wave-shaped rings 8 in the middle section 3 of the stent are arranged equidistantly and at least partially overlapped, the overlapping distance is recorded as L1; the adjacent two wave-shaped rings 8 in the proximal end 4 and the distal end 2 of the stent are arranged at least partially overlapped, the minimum overlapping distance is recorded as L2, and L2 is greater than L1. In this way, for the middle section 3 of the stent, the equidistant arrangement of the adjacent two wave-shaped rings 8 can make the stretching more flexible, especially when bending, one side in the axial direction will be stretched and the other side will be compressed. In this way, the film on the stretched side is stretched as evenly as possible, and the film is not easily damaged. The film on the compressed side is compressed as evenly as possible, so that the film is more smoothly stacked, and the blood flow is not easily stepped.

[0047] As shown in Figure 2 , wherein the end profile of the distal end 2 of the stent is wave-shaped or flower-shaped. For example, the length of the distal end 2 of the stent can be about 8mm, and the end profile is designed to be wave-shaped or flower-shaped, which can bring benefits when the vascular covered stent is implanted in the diseased blood vessel, improve hemodynamics, and slow down the problem of stent port stenosis. Because on the longitudinal section of the blood vessel, the contact area of the blood with the stent mainly depends on the width of the wave-shaped structure of the stent in the direction of the blood flow, therefore the resistance of the blood flow is related to the width of the wave-shaped structure of the stent. The greater the width of the wave-shaped structure at the end, the greater the resistance to the blood flow. Designing the end of the distal end 2 of the stent to be flower-shaped or wave-shaped can reduce the contact area with the blood, so the resistance to the blood flow is smaller, the blood flow velocity and blood flow are greater, and the probability of port stenosis can be relatively reduced.

[0048] As shown in Figure 4 , wherein the inner side wall of the inner membrane 5 is provided with an anticoagulant coating 11. For example, the anticoagulant coating 11 can be a coating containing heparin. In this way, the mid-to-long-term patency rate after stent implantation can be further improved, and the probability of stent thrombosis after surgery can be reduced.

[0049] The bare metal frame 6 is woven from a metal wire, and in this way, the entire bare metal frame 6 has good flexibility and can be bent arbitrarily, and can basically conform to blood vessels of various shapes. In addition, along the axial direction of the bare metal frame 6, it can be straight or non-straight; that is, it can be a straight structure with a constant inner diameter, or a tapered structure with a gradually changing inner diameter (as shown in Figure 5 ), or a horn shape, so that it can better conform to blood vessels of different shapes and obtain better adhesion.

[0050] As shown in Figure 6As shown, both ends of the bare metal frame 6 are flush. For example, the flush end effect can be achieved by changing the distance between two adjacent waveform rings 8, or by changing the shape and size of the waveform structure of the proximal and distal waveform rings 8 to achieve a "compensation" effect and achieve a flush effect. This configuration, compared to a vascular stent with uneven ends, allows for more uniform radial support force at the proximal end 4 and the distal end 2 of the stent, and maintains consistency with the middle section 3 of the stent as much as possible. This flush design also enhances the aesthetics of the entire vascular stent.

[0051] Both the inner membrane 5 and the outer membrane 7 are fluoropolymers; both the inner membrane 5 and the outer membrane 7 are single-layer or multi-layer structures. For example, the width of the outer membrane 7 can be in the range of 0.5mm-3.5mm. The materials of the inner membrane 5 and the outer membrane 7 can be ePTFE membranes and / or ePTFE / FEP (Fluorinated ethylene propylene copolymer) composite membranes, and can be single-layer and / or multi-layer.

[0052] Both the proximal end 4 and the distal end 2 of the stent are provided with radiopaque markers 12. For example, the radiopaque markers 12 can be made of platinum-iridium alloy. This arrangement allows for the fixation of small, lightweight platinum-iridium alloy rings at both ends of the stent, thereby enhancing the visibility of the vascular stent graft.

[0053] like Figure 7 As shown, the vascular stent graft also includes a detachable membrane 13 disposed on the outer wall of the outer membrane 7. Along the width direction of the membrane 13, the thickness of the two side edges of the membrane 13 is greater than the thickness of the middle edge. Along the length direction of the membrane 13, several spaced-apart through-holes 14 are provided along the edge of the membrane 13. For example, the membrane 13 can be an ePTFE membrane. For example, the membrane 13 can be a rectangular sheet structure, with a length 0.2–1.5 cm shorter than the length of the entire vascular stent graft, and the width varying depending on the stent diameter. The membrane 13 can be single-layered or multi-layered. For example, two suture points can be provided to suture the membrane 13 to both ends of the vascular stent graft using polytetrafluoroethylene sutures. Through-holes 14 are punched along the two long edges of the membrane 13; the diameter of the through-holes 14 can be 0.1 mm–1 mm, and the spacing between the holes can be 1 mm–5 mm. In this configuration, the endothelial membrane 13 is wrapped around the vascular stent axially once, and the deploying wire 27 is inserted into the through-holes along the two long sides of the endothelial membrane 13, so that the vascular stent is kept in a contracted state by the endothelial membrane 13. The stent is restrained by the endothelial membrane 13, and the deploying wire 27 and the endothelial membrane 13 work together to form a restraining space to restrain the vascular stent. At the same time, as the deploying wire 27 is withdrawn, the endothelial membrane 13 is gradually unfolded, and the vascular stent is gradually released.

[0054] Since the thickness of the two sides of the membrane 13 is greater than that of the middle, the slightly thicker sides can withstand the reaction force caused by the spatial structure of the unfolding filament and the self-expansion of the support, while ensuring that the membrane itself is thin enough, so that the through holes do not become larger or deformed.

[0055] like Figure 8 As shown, another embodiment provides a delivery device for delivering the aforementioned vascular stent graft, including a conical head 15, a fixing ring 16, a mandrel tube 19, a support tube 17, and an outer tube 18; an inner cavity for placing the vascular stent graft is formed between the outer tube 18, the support tube 17, and the mandrel tube 19. Specifically: the distal end of the mandrel tube 19 is connected to the conical head 15 and the fixing ring 16. A support tube 17 and a stent are sleeved side by side outside the mandrel tube 19. An outer tube 18 is then sleeved outside the support tube 17 and the stent. The support tube 17 includes a single-lumen tube 20, a reinforcing tube 21, and a stainless steel tube 22. The single-lumen tube 20 is sleeved on the mandrel tube 19. The reinforcing tube 21 and the stainless steel tube 22 are sleeved side by side on the single-lumen tube 20. The proximal end of the single-lumen tube 20 is the stainless steel tube 22, and the distal end of the single-lumen tube 20 is the reinforcing tube 21. The fixing ring 16 is located on the mandrel tube 19 and close to the conical head 15. It is used to hook the vascular stent graft when the outer tube 18 is withdrawn to prevent the stent from retracting.

[0056] The conveying device further includes an outer tube seat 23, a fixed handle 24, and a support pipe joint 25. The outer tube seat 23 and the fixed handle 24 are threaded. The outer tube seat 23 is threaded to engage with the outer tube 18 and is connected to the fixed handle 24. The fixed handle 24 is used to unlock / lock the outer tube 18 so that it slides axially on the support pipe 17. The support pipe joint 25 is connected to the end of the stainless steel pipe 22 away from the reinforcing pipe 21.

[0057] The operation of the delivery device is as follows: after the puncture is completed, the diseased blood vessel is imaged and measured, and a vascular covered stent of appropriate size is selected. The guide wire is advanced to the target position of the diseased blood vessel, and the blood vessel lesion segment is dilated with a balloon of appropriate size. The balloon is withdrawn. The delivery device is sent along the guide wire, and the original anchoring zone is determined by the radiopaque markers 12 at both ends of the vascular covered stent. The vascular covered stent must extend at least 1 cm beyond the proximal and distal edges of the target position of the diseased blood vessel. The fixing handle 24 is loosened, one hand holds the stainless steel tube 22 of the support tube 17 and the support tube joint 25 stationary, and the other hand holds the outer tube 18 and withdraws it back smoothly and slowly until the vascular covered stent is completely separated from the outer tube 18. The entire fixing handle 24 is loosened, and the fixing handle 24 falls off the outer tube seat 23 and slides onto the stainless steel tube 22. The outer tube 18 is held stationary, and the other hand holds the stainless steel tube 22 and the support tube joint 25 and withdraws them back smoothly and slowly until the conical head 15 is completely withdrawn into the outer tube 18. The speed of withdrawal can be increased until the support tube 17 is withdrawn from the outer tube 18. A balloon of appropriate size is sent along the guide wire and placed inside the vascular covered stent. The vascular covered stent is dilated using a pressurized balloon. After completion, the balloon is withdrawn, and the outer tube 18 is withdrawn. The wound is sutured.

[0058] As Figure 9 , Figure 10 shown, another embodiment provides a delivery device for delivering the vascular covered stent described above, which includes a conical head 15, a fixing ring 16, a mandrel tube 19, a support tube 17, an outer tube 18, and a deployment wire 27. Unlike the previous embodiment, the support tube 17 comprises a double-lumen tube 26, a reinforcing tube 21, and a stainless steel tube 22. The double-lumen tube 26 is sleeved on the mandrel tube 19 through one of the lumens. The conical head 15 is provided with a hidden hole, and one end of the deployment wire 27 passes through the other lumen of the double-lumen tube 26, passes through the through holes 14 on both edges of the membrane 13 in turn (the membrane 13 has constrained the stent to a contracted state), and is then inserted into the hidden hole of the conical head 15. The fixing ring 16 is arranged on the mandrel tube 19 and close to the conical head 15, and is used to hook the vascular covered stent when the outer tube 18 is withdrawn.

[0059] The delivery device further comprises an outer tube seat 23, a fixed handle 24 and a support tube joint 25. The support tube joint 25 has a Y joint and a pull wire handle 28. The outer tube seat 23 and the fixed handle 24 have threads. The outer tube seat 23 is screwed to the outer tube 18 and connected to the fixed handle 24. The fixed handle 24 is used to unlock / lock the outer tube 18 from sliding axially on the support tube 17. The support tube joint 25 is connected to the end of the stainless steel tube 22 away from the reinforcing tube 21. The other end of the deployment wire 27 passes through the other lumen of the double-lumen tube 26, then through the deployment wire hole in the Y joint of the support tube joint 25, and is connected to the pull wire handle 28. When the pull wire handle 28 is loosened and pulled back, the deployment wire 27 is also pulled back. As the deployment wire 27 is continuously pulled back, the covered stent is steadily self-expanded until it is completely released. Because the covered stent is still restrained by the film 13 and the deployment wire 27 at this time, if the doctor is not skilled enough or the patient's diseased blood vessel is complex, the doctor can change the anchoring area by retracting the outer tube 18 into the outer tube 18 again before the outer tube 18 completely leaves the stent.

[0060] In addition, in another embodiment, when the deployment wire 27 is retracted from the two through holes at the edge of the film 13 to release the stent, the radial force at the stent release site is still too large to bounce and impact the blood vessel, and the impact force will cause the stent to require a larger release force and unstable release. Figure 11 、 Figure 12 、 Figure 13 As shown in the drawings, the edge of the stent distal end 2 is provided with a lug 36, and the number of lugs 36 is matched with the number of ring hooks 37. The ring hooks 37 can be two or one. The lugs 36 can be hung in the same direction or upside down. The lugs 36 protrude from the stent distal end 2 by about 1-3 mm. The lugs 36 are hung on the ring hooks 37 of the fixed ring 16, and are used to hook the covered stent when the outer tube 18 is retracted, i.e., the stent distal end is still hung at the fixed ring. In this way, the impact force caused by the retraction of the deployment wire 27 can be prevented from causing the stent distal end to impact the blood vessel radially, making the entire release process more gentle and stable. At the same time, it can prevent the stent distal end from being pulled back together with the deployment wire 27 when the deployment wire 27 is retracted, avoiding the generation of a large axial force on the stent, which may damage the stent itself or the blood vessel. (After the deployment wire 27 is retracted, the stent is released against the blood vessel. If the stent distal end is pulled back together with the deployment wire, while the stent proximal end is resisted by the support tube 17 and cannot be retracted, the stent distal end will be bounced back by the reaction force of the support tube 17, which will scratch the blood vessel twice.)

[0061] Embodiment one:

[0062] As Figure 14 shown, abdominal aortic aneurysm combined with iliac artery aneurysm, clinically can see many lesions endangering external iliac artery, common iliac artery and even internal iliac artery. It is difficult to use endovascular repair of abdominal aorta to treat such lesions. If the internal iliac artery is occluded during the operation, although the distal 2 anchor area of the stent is extended to the external iliac artery, it can achieve satisfactory isolation effect, but the corresponding complications are also common. Common complications of internal iliac artery embolism include claudication of gluteal muscles, pelvic ischemia, spinal cord ischemia or acute ischemia of lower extremities. The reconstruction of internal iliac artery can choose endovascular repair, and the iliac artery branch stent system is one of the choices for endovascular reconstruction of internal iliac artery. The iliac branch stent technology is to use the iliac bifurcated stent to retain the opening of the ipsilateral internal iliac artery, and at the same time, the internal iliac artery covered stent is implanted, which is bridged with the iliac branch stent 29, so as to isolate the aneurysm cavity and reconstruct the internal iliac artery. The use of the body 1 and the iliac branch stent 29 can obtain better treatment effect. In this embodiment, the iliac branch stent 29 is implanted from the ipsilateral common femoral artery, the proximal body 30 and the internal iliac branch 31 of the iliac branch stent are first released, the internal iliac branch 31 is above the opening of the internal iliac artery and as close to the opening as possible, from the contralateral common femoral artery or upper limb brachial artery approach, a multifunctional catheter is selected to guide the loach guide wire into the internal iliac artery, and the loach guide wire is exchanged for a hard guide wire. The anti-coagulation coating 11 vascular covered stent system is sent into the internal iliac artery along the hard guide wire, the outer tube 18 is withdrawn backward to release the vascular covered stent, the internal iliac branch 31 of the iliac branch stent 29 is bridged, and finally the external iliac branch 32 of the iliac branch stent 29 is completely released.

[0063] The anti-coagulation coating 11 vascular covered stent of the embodiment one of the present application is also applied to patients with symptomatic peripheral arterial disease, and can be used alone for superficial femoral artery lesions or iliac artery lesions.

[0064] Embodiment two:

[0065] Dialysis vascular access is called the lifeline of uremic patients. However, as the disease progresses, hemodialysis access may develop stenosis, thrombosis, pseudoaneurysm, central vein occlusive disease and other complications. Percutaneous transluminal balloon angioplasty (PTA) is currently the first-line treatment for stenosis. However, based on balloon PTA treatment, the patency rate is not good, and doctors need to intervene repeatedly, which brings heavy burden to doctors and patients. Central vein stenosis or occlusion is one of the main factors leading to the failure of hemodialysis access in uremic patients. With the continuous development of endovascular interventional devices, from simple balloon dilation and metal bare stent implantation to today's covered stent implantation, the patency rate after central vein stenosis surgery has been continuously improved, and the patency time has been gradually prolonged. When PTA is ineffective (residual stenosis > 30%), repeated short-term restenosis lesions, anatomic compression lesions, and occlusive lesions (risk of re-opening) can be performed in one stage. The patency rate of covered stent is better than that of metal bare stent, but it needs to avoid affecting the backflow of other main central veins.

[0066] AsFigure 15 , Figure 16 As shown, unlike Embodiment 1, the overall structure is not straight or conical. The main body 1 of this embodiment has a trumpet-shaped structure, with the proximal end of the stent having a larger diameter than the distal end, and the diameter-changing region is 3 cm long. This design is suitable for treating stenosis or thrombotic occlusion of venous anastomoses in arteriovenous access grafts. The operator punctures the fistula vein in the arteriovenous access channel 33, routinely places a sheath, and then performs angiography to clarify the extent of the lesion. A balloon dilation catheter is then inserted along the guidewire into the stenotic vein, and the target lesion is pre-dilated using the balloon. The balloon catheter is then withdrawn, and a vascularized stent graft is then inserted along the guidewire. After stent release, post-stent dilation is performed.

[0067] Example 3:

[0068] Lesions involving the aortic arch, especially those involving the reconstruction of supra-arch branches, present the greatest challenge in thoracic aortic repair surgery. Branched aortic endovascular stent grafts, with their single branch, are not sufficiently fitted and flexible to the actual lesion. Furthermore, the current market lacks a specific category of peripheral vascular endovascular stent grafts that can be used in conjunction with supra-arch endovascular stent grafts to complete the full arch reconstruction in branch vessels.

[0069] like Figure 17 As shown, in this embodiment, the main body 1 is used in conjunction with the supra-arc covered stent 34. After the supra-arc covered stent 34 is placed, a guidewire and vascular sheath assembly are first inserted from the brachiocephalic trunk. Then, the guidewire is advanced into the first branch stent of the supra-arc covered stent 34, and then a suitable-sized main body 1 is inserted along the guidewire to bridge the brachiocephalic trunk. The same method is then used to insert the guidewire from the left common carotid artery and left clavicular artery into the second or third branch stent at the rear end, and then a suitable-sized anticoagulant coated vascular covered stent 11 is inserted along the guidewire to bridge the left common carotid artery and left clavicular artery, respectively. Alternatively, a guidewire can be inserted from the femoral artery into the main body of the supra-arc covered stent 34, through the second or third branch stent, into the left common carotid artery and left clavicular artery, and then a suitable-sized vascular covered stent is inserted along the guidewire to bridge the left common carotid artery and left clavicular artery, thereby achieving endovascular reconstruction of the supra-arc three-branch vessels.

[0070] Example 4:

[0071] When aortic aneurysms in the thoracic and abdominal regions involve visceral arteries and cannot be repaired using conventional surgical methods, reconstruction of the four visceral arteries—including the bilateral renal arteries, superior mesenteric artery, and celiac trunk—is necessary to avoid a series of complications caused by visceral artery ischemia. However, due to significant individual differences in the actual visceral arteries of these four branches, the standard size of the 35-inch interthoracic and abdominal covered stent is limited and requires customization, making it difficult to widely adopt. Therefore, it is crucial to use peripheral vascular covered stents in conjunction with interthoracic and abdominal stents to reconstruct visceral arteries during surgery, based on the specific circumstances. Similar to supra-aortic branch reconstruction, there is currently no dedicated peripheral vascular covered stent available on the market.

[0072] As Figure 18 shown, the body 1 in the embodiment is used in cooperation with the intercostal and abdominal membrane stent 35. After the intercostal and abdominal membrane stent 35 is placed, a guide wire and a blood vessel sheath are sent into the femoral artery first, then the guide wire is sent forward into the first branch stent of the intercostal and abdominal membrane stent 35, and then a blood vessel membrane stent of a suitable specification is sent along the guide wire to bridge the superior mesenteric artery. The guide wire is sent forward in the same way to the second branch stent or the third branch stent to send into the bilateral renal arteries, and then a blood vessel membrane stent of a suitable specification is sent along the guide wire to bridge the bilateral renal arteries, so as to realize the endoluminal reconstruction of the visceral artery branch vessels.

[0073] In summary, the structure of the blood vessel membrane stent in the application is special. The outer membrane 7 incompletely covers each wave ring 8 in the middle segment 3 of the stent, and exposes the wave crest 9 and the wave trough 10, which provides excellent bending performance for the stent and enables the stent to maintain the basic original cross-sectional area in the inner surface of the lumen.

[0074] The flexibility of the stent is better, and the adhesion is higher.

[0075] The inner wall of the inner membrane 5 in the blood vessel membrane stent in the application contains an anticoagulant coating 11, which reduces thrombosis.

[0076] The mechanical structure of the delivery device in the application is unique and easy to operate.

[0077] Obviously, the above embodiments are only examples for clear illustration, and are not limitations on the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. It is not necessary and impossible to enumerate all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the application.

Claims

1. A vascular covered stent, characterized by, The application relates to a blood vessel covered stent, which comprises a body (1) divided into a stent distal end (2), a stent middle section (3) and a stent proximal end (4) along the axial direction of the body (1); the body (1) comprises an inner membrane (5), a bare metal framework (6) and an outer membrane (7) along the radial direction of the body (1) and from inside to outside; the bare metal framework (6) is composed of a plurality of connected wave-shaped rings (8) along the axial direction of the bare metal framework (6), and each wave-shaped ring (8) is a wave-shaped structure comprising wave crests (9) and wave troughs (10). The outer membrane (7) located at the stent middle section (3) incompletely covers the wave-shaped rings (8), so that the wave crests (9) and the wave troughs (10) of the wave-shaped rings (8) are exposed.

2. The blood vessel covered stent according to claim 1, wherein the outer membrane (7) located at the stent proximal end (4) and the stent distal end (2) fully covers the wave-shaped rings (8); and the inner membrane (5) at the two ends of the bare metal framework (6) is connected with the outer membrane (7) through the bare metal framework (6), so as to wrap the bare metal framework (6).

3. The blood vessel covered stent according to claim 1, wherein the adjacent two wave-shaped rings (8) located at the stent middle section (3) are arranged at equal distances and at least partially overlap, and the overlapping distance is denoted as L1; and the adjacent two wave-shaped rings (8) located at the stent proximal end (4) and the stent distal end (2) at least partially overlap, and the minimum overlapping distance is denoted as L2, and L2 is greater than L1.

4. The blood vessel covered stent according to claim 1, wherein the end profile of the stent distal end (2) is wave-shaped or flower-shaped.

5. The blood vessel covered stent according to claim 1, wherein the inner side wall of the inner membrane (5) is provided with an anticoagulant coating (11).

6. The blood vessel covered stent according to claim 1, wherein the two end faces of the bare metal framework (6) are arranged flush.

7. The blood vessel covered stent according to any one of claims 1-6, further comprising an attached membrane (13) arranged on the outer side wall of the outer membrane (7); along the width direction of the attached membrane (13), the thickness of the two side edges of the attached membrane (13) is greater than the thickness of the middle part, and along the length direction of the attached membrane (13), the edge of the attached membrane (13) is provided with a plurality of spaced-apart through holes (14). A device for delivering the blood vessel covered stent according to any one of claims 1-6, which comprises a tapered head (15), a fixing ring (16), a support tube (17) and an outer tube (18); the support tube (17) comprises a mandrel tube (19), a single-lumen tube (20), a reinforcing tube (21) and a stainless steel tube (22); the single-lumen tube (20) is sleeved on the mandrel tube (19); the reinforcing tube (21) and the stainless steel tube (22) are sequentially sleeved on the single-lumen tube (20) in a direction away from the mandrel tube (19); and the tapered head (15) is connected with the fixing ring (16). ​ ​ ​ ​ ​ ​ ​ ​ 8. A delivery device characterized by, ​ ​ ​ ​ The outer tube (18) is sleeved outside the support tube (17), and an inner cavity for placing the vascular covered stent is formed between the outer tube (18) and the mandrel tube (19); The conical head (15) is fixed at the end of the mandrel tube (19) away from the single-lumen tube (20); The fixing ring (16) is arranged on the mandrel tube (19) and close to the conical head (15), and is used for hooking the vascular covered stent when the outer tube (18) is retracted.

9. A delivery device characterized by, The delivery device for the vascular covered stent of claim 7 comprises a conical head (15), a fixing ring (16), a support tube (17), an outer tube (18) and a deployment wire (27); The support tube (17) comprises a mandrel tube (19), a double-lumen tube (26), a reinforcing tube (21) and a stainless steel tube (22); The double-lumen tube (26) is sleeved on the mandrel tube (19) through one of the tube cavities; The reinforcing tube (21) and the stainless steel tube (22) are sequentially sleeved on the double-lumen tube (26) in the direction away from the mandrel tube (19); The outer tube (18) is sleeved outside the support tube (17), and an inner cavity for placing the vascular covered stent is formed between the outer tube (18) and the mandrel tube (19); The conical head (15) is fixed at the end of the mandrel tube (19) away from the double-lumen tube (26), and the conical head (15) is provided with a hidden hole; The fixing ring (16) is arranged on the mandrel tube (19) and close to the conical head (15), and is used for hooking the vascular covered stent when the outer tube (18) is retracted; One end of the deployment wire (27) is sequentially threaded into the through holes (14) on the two edges of the membrane (13) and inserted into the hidden hole on the conical head (15), and the other end of the deployment wire (27) is threaded out through the other tube cavity of the double-lumen tube (26).

10. The delivery device of claim 9, wherein It further comprises an outer tube seat (23), a fixed handle (24) and a support tube joint (25); The outer tube seat (23) and the fixed handle (24) are provided with threads, the outer tube seat (23) is threadedly engaged with the outer tube (18) and connected with the fixed handle (24), and the fixed handle (24) is used for independently unlocking / locking the outer tube (18) to axially slide on the support tube (17); The support tube joint (25) is connected with the end of the stainless steel tube (22) away from the reinforcing tube (21); The other end of the deployment wire (27) is connected with the support tube joint (25) after being threaded out through the other tube cavity of the double-lumen tube (26).

11. The delivery device of claim 9, wherein The fixing ring (16) is provided with a ring hook (37), and the edge of the stent distal end (2) is provided with a hanging ear (36); the hanging ear (36) is hung on the ring hook (37), and the ring hook (37) is used for hooking the vascular covered stent when the outer tube (18) is retracted, so that the stent distal end (2) is still hung on the fixing ring (16).

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