Covered stent, stent system and manufacturing method of stent system

Abstract

The invention relates to a covered stent, a stent system and a manufacturing method of the stent system.The covered stent comprises a main stent body, a covering film and binding wires, the main stent body comprises a main corrugated ring and a main covering film, the main corrugated ring is covered with the main covering film, the binding wires comprise the first binding wire, and the covering film and the main stent body are connected to one side of the main stent body through the first binding wire; the covered stent further comprises a first positioning piece and a second positioning piece, the first positioning piece is arranged at the proximal end of the main stent, the second positioning piece is arranged at the proximal end of the envelope, and when the covered stent is in a natural expansion state, when the envelope is naturally attached to the main stent in the circumferential direction, the envelope is located at the proximal end of the main stent. The first positioning piece and the second positioning piece are roughly located on the same radial line. According to the covered stent provided by the invention, a second fixed connection point of the envelope of the covered stent and the main stent can be determined, and the envelope is prevented from being fixed to the circumferential opposite side of the target position of the main stent, so that the problem of release of the proximal end of the main stent is avoided.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and particularly to a covered stent, a stent system and a manufacturing method of the stent system. Background Art

[0002] In the past ten-odd years, endovascular exclusion with aortic covered stents has been widely used in treating lesions such as aneurysms and aortic dissections of the thoracic and abdominal aorta. It has definite curative effects, less trauma, quick recovery and fewer complications, and has become a first-line treatment method. For special lesion sites such as the aortic arch, celiac trunk, bilateral renal arteries or superior mesenteric artery where the aneurysm or aortic dissection involves branches, using a covered stent will affect the blood supply of the branch blood vessels. In response to this situation, corresponding holes are provided on the covered stent, and the blood flow supply of the branch blood vessels is perfused through the holes. Usually, the diameter of the holes is close to that of the branch blood vessels. How to ensure that the holes can just coincide with the branch blood vessels is the key to branch reconstruction. The common method is to circumferentially constrain the stent with a tying wire so that the stent is radially compressed. After the stent is released from the sheath of the delivery device, it is in a radially compressed state, so that the doctor can operate and align it during the operation, and the stent can adjust its position for precise positioning. Or, for blood vessel positions where the aortic aneurysm or aortic dissection does not involve branches but has certain requirements for stent positioning, the above semi-restrained method can also be used to further precisely position the stent before it is completely released.

[0003] However, the tying wires currently used may cause the following problems because they cannot completely wrap the axis of the stent: Since the tying wire fails to cover a part of the stent, and the metal wires on the stent have a strong self-expansion force, local warping occurs, making the outer surface of the stent rough. When the doctor adjusts the position of the stent, the warped part rubs against the blood vessel wall, resulting in the detachment of the adherent thrombus on the blood vessel wall and flowing into the branch blood vessels, increasing the surgical risk of the patient and affecting the postoperative treatment effect. To solve the above problems, the stent can be radially constrained by wrapping it with an envelope, which can completely wrap all parts of the stent, so that the compressed shape of the stent wrapped by the envelope is uniform in the axial direction. At the same time, it can be ensured that the surface of the restrained stent is relatively smooth when it contacts the blood vessel wall, and the envelope can be fixed to the stent by suturing. However, when there is more than one fixed connection point between the envelope and the main stent, it is not conducive to wrapping the envelope around the main stent, thus not conducive to the loading of the covered stent. Or, in order not to affect the loading of the covered stent, and then suture the second fixed point after the main stent is wrapped by the envelope, it may cause the other suture position of the envelope to be sutured to the circumferential opposite side of the target position of the main stent, resulting in the release problem of the proximal end of the main stent. Summary of the Invention

[0004] At least one technical problem solved by the present invention is how to set two fixed connection points between the envelope and the main stent of the covered stent to avoid the release problem of the proximal end of the main stent.

[0005] The present invention provides a covered stent, which includes a main stent, a covering membrane, and tying wires. The main stent includes main wave loops and a main covering membrane. The main covering membrane covers the main wave loops. The tying wires include a first tying wire. The covering membrane and the main stent are connected to one side of the main stent through the first tying wire. The covered stent further includes a first positioning member and a second positioning member. The first positioning member is arranged at the proximal end of the main stent, and the second positioning member is arranged at the proximal end of the covering membrane. When the covered stent is in a natural expansion state and the covering membrane naturally adheres to the main stent circumferentially, the first positioning member and the second positioning member are substantially on the same radial line.

[0006] In one embodiment, the covered stent further includes a second tying wire, and the first positioning member is configured as the second tying wire.

[0007] In one embodiment, the second positioning member is configured as a protrusion, and the protrusion protrudes from the proximal end face of the main covering membrane;

[0008] Or, the second positioning member is configured as a radiopaque structure.

[0009] In one embodiment, the main stent includes a tying attachment, and the tying attachment includes a part of the main wave loops or tying wires. The tying attachment extends along the main covering membrane. The main covering membrane includes a first perforation and a second perforation, and the first perforation and the second perforation are respectively arranged on both sides of the extending direction of the tying attachment. The first tying wire passes through the first perforation and the second perforation and straddles the tying attachment.

[0010] In one embodiment, the first tying wire is connected to the wave rod, wave peak, or wave valley of the main wave loop;

[0011] Or, one main wave loop is connected by a steel sleeve to form a corrugated ring, the first tying wire is connected to the main wave loop, and the first tying wire is close to the edge of the steel sleeve.

[0012] In one embodiment, the main covering membrane includes a linear film, and the linear film winds along the circumference of the main covering membrane;

[0013] The first tying wire is connected to the wave rod of the main wave loop, and at least one linear film is arranged on each of the proximal end side and the distal end side of the first tying wire;

[0014] Or, the first tying wire is connected to the wave peak of the main wave rod, and at least one linear film is arranged on the distal end side of the first tying wire;

[0015] Alternatively, the first tying thread is connected to the trough of the main body wave rod, and at least one linear film is arranged on the distal end side of the first tying thread.

[0016] In one embodiment, the main body film coating includes a linear film which is wound circumferentially along the main body film coating; the shortest distance L1 from one linear film to the edge of the first perforation in the axial direction satisfies: L1 ≤ 3 mm, and / or the shortest distance L2 from one linear film to the edge of the second perforation in the axial direction satisfies: L2 ≤ 3 mm.

[0017] In one embodiment, the straight line connecting the geometric centers of the holes of the first perforation and the second perforation is defined as W1. The linear film includes a first linear film which is arranged on the proximal end side of the first perforation and the second perforation. The included angle β1 between the first linear film and W1 satisfies: 0° ≤ β1 ≤ 20°.

[0018] In one embodiment, the linear film further includes a second linear film which is arranged on the distal end side of the first perforation and the second perforation. The included angle β2 between the second linear film and W1 satisfies: 0° ≤ β2 ≤ 20°.

[0019] In one embodiment, the envelope includes a buffer member, a third perforation and a fourth perforation. The buffer member extends along the plane where the envelope is located. The third perforation and the fourth perforation are respectively arranged on both sides of the extending direction of the buffer member. The first tying thread passes through the first perforation and the second perforation, crosses the tying attachment, then passes through the third perforation and the fourth perforation, crosses the buffer member and then ties a knot.

[0020] In one embodiment, the film-covered stent further includes a branch stent, and the lumen of the branch stent is communicated with the lumen of the main body stent. The main body stent includes a first side and a second side in the circumferential direction. The envelope is connected to the first side of the main body stent, and the branch stent is connected to the second side of the main body stent; the main body stent includes a proximal end segment, and at least one tying attachment is arranged on the first side of the proximal end segment.

[0021] In one embodiment, the proximal end segment successively includes a first main body wave loop and a second main body wave loop from the proximal end to the distal end, and the tying thread further includes a second tying thread;

[0022] The first tying thread is arranged on the wave rod or wave peak or wave trough on the first side of the first main body wave loop, and the second tying thread is arranged on the wave rod or wave peak or wave trough on the first side of the second main body wave loop;

[0023] Alternatively, the main body stent includes a bent section, which is closer to the distal end than the proximal end section. The bent section sequentially includes a third main body wave loop and a fourth main body wave loop from the proximal end to the distal end. The first tying wire is disposed on the wave rod or wave peak or wave valley on the first side of the first or second main body wave loop, and the second tying wire is disposed on the wave rod or wave peak or wave valley on the first side of the third or fourth main body wave loop.

[0024] The present invention also provides a stent system, which includes the covered stent as described above. The stent system further includes a delivery device, which includes a sheath core assembly, a support rod, a sheath tube, and a diameter-releasing member. The sheath core assembly includes an inner sheath core and an outer sheath core. The inner sheath core, the outer sheath core, the support rod, and the sheath tube are sequentially sleeved from the inside to the outside. The support rod is sleeved outside the sheath core assembly. The delivery device further includes a guiding head, which is disposed at the distal end of the inner sheath core. There is a spaced arrangement between the distal end of the support rod and the proximal end of the guiding head to form a loading space for the covered stent. The diameter-releasing member cooperates with the envelope to realize radial constriction and release of the covered stent. The covered stent is loaded into the loading space, and the first positioning member and the second positioning member are sutured and fixed by a second suture.

[0025] In one embodiment, the covered stent further includes an embedded stent, which is disposed on the distal end side of the branch stent.

[0026] The present invention also provides a manufacturing method of a stent system, which is used to manufacture the stent system as described above. Provide a covered stent, and with the fixed connection point between the envelope and the first tying wire of the main body stent as the boundary, the main body stent includes a first part and a second part;

[0027] The main body stent is sleeved on the sheath core assembly, then the first part of the main body stent is radially compressed and loaded into a first auxiliary sleeve, the second part of the main body stent is radially compressed and loaded into a second auxiliary sleeve, and then the envelope is wrapped on the outer surface of the auxiliary sleeve. At the same time, the diameter-releasing member is axially passed through the envelope to realize radial compression and wrapping of the envelope on the main body stent;

[0028] The auxiliary sleeves are withdrawn, the first positioning member is sutured to the second positioning member, and the sutured covered stent is loaded into the sheath tube of the delivery device to complete the loading of the covered stent into the sheath, forming the stent system.

[0029] One technical effect of an embodiment of the present invention is that by arranging the first positioning member and the second positioning member on the same radial line, or the first positioning member and the second positioning member being substantially on the same radial line, the second fixed connection point between the envelope of the covered stent and the main stent can be determined, preventing the envelope from being fixed to the circumferential opposite side of the target position of the main stent, thereby avoiding the release problem at the proximal end of the main stent. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic structural diagram of a covered stent provided by an embodiment of the present invention;

[0031] Figure 2 Partial structural diagram of a covered stent provided by an embodiment of the present invention (partial main covering film omitted);

[0032] Figure 3 Partial structural diagram of the cooperation between a covered stent (partial main covering film omitted) provided by an embodiment of the present invention and a tying wire;

[0033] Figure 4 Planar development view of an envelope provided by an embodiment of the present invention;

[0034] Figure 5 Schematic structural diagram of a covered stent provided by another embodiment of the present invention;

[0035] Figure 6 Schematic structural diagram of the connection between an envelope and a main stent provided by an embodiment of the present invention (main covering film omitted);

[0036] Figure 7 Schematic structural diagram of a partial main stent provided by an embodiment of the present invention;

[0037] Figure 7a Schematic structural diagram of a partial main stent provided by another embodiment of the present invention;

[0038] Figure 7b Schematic structural diagram of a partial main stent provided by yet another embodiment of the present invention;

[0039] Figure 8 is Figure 7 enlarged view at B in;

[0040] Fig. 9 Schematic structural diagram of a covered stent provided by yet another embodiment of the present invention;

[0041] Fig.10 is Fig. 9 bending state diagram when applied to a curved blood vessel;

[0042] Fig.11Schematic diagram of the structure of the covered stent provided by another embodiment of the present invention;

[0043] Fig.12 is Fig.11 Diagram of the bending state when applicable to a curved blood vessel;

[0044] Fig.13 Schematic diagram of radially compressing the main stent and loading it into two auxiliary sleeves from both ends respectively;

[0045] Fig.14 is relative to Fig.13 Schematic diagram of loading the auxiliary sleeves at both ends to a position where the end is close to the fixed connection point of the envelope and the main stent;

[0046] Fig.15 Schematic diagram of the envelope wrapping around the outer surface of the sleeve, and at the same time passing the beam diameter releasable member through the limiting hole to realize the radial compression and wrapping of the envelope on the main stent;

[0047] Fig.16 Schematic diagram of the envelope and the main stent after withdrawing the auxiliary sleeve ( Figure 13-Figure 16 is the method step of using the auxiliary sleeve to wrap the envelope around the main stent and radially compress the main stent when only one fixed connection point is provided between the envelope and the main stent);

[0048] Fig.17 Schematic diagram of when two fixed connection points are set and the main stent cannot be fully radially compressed by using the auxiliary sleeve;

[0049] Fig.18 Schematic diagram of the structure of the covered stent provided by an embodiment of the present invention;

[0050] Fig.19 Top view of the envelope of the covered stent provided by an embodiment of the present invention when naturally adhering to the main stent along the circumference;

[0051] Fig. 20 Schematic diagram of the structure of the envelope provided by an embodiment of the present invention;

[0052] Fig.20a Schematic diagram of the structure of the envelope provided by another embodiment of the present invention;

[0053] Fig.20b Schematic diagram of the structure of the envelope provided by still another embodiment of the present invention;

[0054] Figure 21-22 Schematic diagram of a partial manufacturing method of a stent system provided by the present invention;

[0055] Fig.23 is Fig.11 right view;

[0056] Fig.24 is Fig.11 Schematic structural diagram of a covered stent (showing the branch stent part inside the main stent)

[0057] Fig.24a Fig.24 Enlarged view at point C in

[0058] Fig.25 Schematic structural diagram of a stent system provided by an embodiment of the present invention

[0059] Fig.26 Schematic structural diagram of a support rod provided by an embodiment of the present invention from an axial perspective

[0060] Fig.26a Schematic structural diagram of a support rod provided by another embodiment of the present invention from an axial perspective

[0061] Fig. 27 Schematic structural diagram of a covered stent of a stent system provided by an embodiment of the present invention being radially compressed and wrapped by a wrapping film (the beam diameter releasable member includes a beam diameter guide wire)

[0062] Fig.28 Schematic structural diagram of a covered stent of a stent system provided by another embodiment of the present invention being radially compressed and wrapped by a wrapping film (the beam diameter releasable member includes a releasable suture structure)

[0063] Fig.29 is Fig.28 Schematic structural diagram of the partial release of the constraint section in

[0064] Fig.30 Partial schematic structural diagram of a guide head and an inner sheath core provided by an embodiment of the present invention

[0065] Fig.31 Schematic structural diagram of a clamping member in a post - release structure provided by an embodiment of the present invention

[0066] Fig.32 Diagram of the closable state formed by the cooperation and engagement of the clamping member and the clamping groove of a post - release structure provided by an embodiment of the present invention

[0067] Fig.33 Guide catheter passage through the branch blood vessel established when the stent system provided by an embodiment of the present invention is implanted at the aortic arch

[0068] Fig.34 Schematic diagram of the stent system provided by an embodiment of the present invention being introduced along a super - stiff guide wire into the aortic arch

[0069] Fig.35Schematic diagram of the preliminary positioning of the stent system provided by an embodiment of the present invention at the aortic arch after the sheath tube is withdrawn;

[0070] Fig.36 Schematic diagram of the branch opening of the covered stent of the stent system provided by an embodiment of the present invention aligned with the branch vessel;

[0071] Figure 37 to Figure 38 Schematic diagram of pulling the lead segment of the beam diameter guide wire or suture structure backward to deploy the main stent from the proximal end to the distal end in sequence and adhere to the wall for the stent system provided by an embodiment of the present invention;

[0072] Fig.39 For relative Fig.38 Schematic diagram of withdrawing the branch sheath to deploy the branch stent to fit the branch vessel;

[0073] Fig.40 Schematic diagram of the structure of the stent system provided by another embodiment of the present invention;

[0074] Fig.41 For Fig.40 Schematic diagram of the structure of the covered stent of the stent system in

[0075] Fig.42 For Fig.41 Enlarged view at D in

[0076] Fig.43 Schematic diagram of the structure of the preset catheter in the stent system provided by another embodiment of the present invention;

[0077] Fig.44 Schematic diagram of the ultra - stiff guide wire being introduced into the aortic arch before the stent system provided by another embodiment of the present invention is implanted;

[0078] Fig.45 Schematic diagram of the stent system provided by another embodiment of the present invention being introduced along the ultra - stiff guide wire into the aortic arch;

[0079] Fig.46 For relative Fig.45 Schematic diagram of withdrawing the sheath tube to expose the covered stent in a state of being wrapped by the encapsulation film out of the sheath tube;

[0080] Fig.47 For relative Fig.46 Schematic diagram of rotating the preset catheter to disengage the pre - bent section of the preset catheter from the gap of the first bare coil;

[0081] Fig.48 For relative Fig.47 Schematic diagram of pushing the preset catheter to directly select the preset catheter into the branch vessel;

[0082] Fig.49 For relative Fig.48 Schematic diagram of pushing the front support system until the annular support is facing the left subclavian artery;

[0083] Fig.50 For relative Fig.49 Schematic diagram of withdrawing the beam diameter guide wire to open the envelope and the covered stent naturally expanding to basically adhere to the wall;

[0084] Fig.51 For relative Fig.50 Schematic diagram of releasing the first bare wave ring using the post - release structure and withdrawing the pre - placed catheter and the delivery device;

[0085] Fig.52 For relative Fig.51 Schematic diagram of implanting an external extended stent along the branch guide wire and withdrawing the branch guide wire;

[0086] Fig.53 Schematic structural diagram of the covered stent provided by another embodiment of the present invention;

[0087] Fig.54 For Fig.53 right view;

[0088] Fig.55 For Fig.53 Schematic diagram of the covered stent of being introduced into the aortic arch by the stent system along the ultra - stiff guide wire, withdrawing the sheath tube to expose the envelope outside the sheath tube, and selecting the pre - placed catheter into the left common carotid artery;

[0089] Fig.56 For relative Fig.55 Schematic diagram of pushing the front support system until the annular support is facing the left common carotid artery;

[0090] Fig.57 For relative Fig.56 Schematic diagram of withdrawing the beam diameter guide wire to open the envelope and the covered stent naturally expanding to basically adhere to the wall;

[0091] Fig.58 For relative Fig.57 Schematic diagram of releasing the first bare wave ring using the post - release structure and withdrawing the pre - placed catheter and the delivery device;

[0092] Fig.59 For relative Fig.58 Schematic diagram of implanting an external extended stent along the branch guide wire into the left common carotid artery and withdrawing the branch guide wire;

[0093] Fig.60 For relative Fig.59 Implanting an external small stent matching the embedded stent into the left subclavian artery. Detailed implementation mode

[0094] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0095] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be a middle element at the same time. The terms "inner", "outer", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments.

[0096] "Axial direction" generally refers to the length direction of the medical device when it is being delivered, and "radial direction" generally refers to the direction perpendicular to its "axial direction", and the "axial direction" and "radial direction" of any part of the medical device are defined based on this principle. In addition, when describing a lumen stent or a covered stent, the orientation can be defined according to the blood flow direction in the blood vessel. In the present invention, it is defined that the blood flow flows from the proximal end of the stent to the distal end. In the field of interventional medical devices, generally for a delivery device that delivers a medical device when implanting the medical device into the human body or an animal body, the end closer to the operator is called the "proximal end", and the end farther from the operator is called the "distal end", and the "proximal end" and "distal end" of any part of the delivery device are defined based on this principle.

[0097] The "wave loop" in the present invention is a closed ring structure, which can also be called a waveform ring, and is made by braiding or cutting a metal elastic material. The two ends of the metal elastic material in the shape of a wave of a single main wave loop can be connected by a steel sleeve, so that the main wave loop is in a ring shape. The metal elastic material includes known materials implanted in medical devices or combinations of various biocompatible materials, such as alloys of two or more single metals among cobalt, chromium, nickel, titanium, magnesium, iron, and 316L stainless steel, nickel-titanium-tantalum alloy, etc., or other metal elastic materials with biocompatibility. The wave loop has the ability of radial expansion, can be radially contracted under the action of an external force, and can self-expand and return to its initial shape and maintain its initial shape after the external force is withdrawn. Therefore, after being implanted into the lumen, it can closely adhere to the inner wall of the lumen through its radial supporting force. The waveform of the wave loop is not limited, including Z-shaped waves, M-shaped waves, V-shaped waves, sine waves, etc. The wave loop includes a plurality of wave peaks (also called proximal vertices), a plurality of wave valleys (also called distal vertices), and wave rods connecting adjacent wave peaks and wave valleys. Among them, one vertex (proximal vertex or distal vertex) and the two wave rods connected to the vertex form a single wave.

[0098] The present invention provides a covered stent 100, such as Figure 1 As shown in the figure, the covered stent 100 includes a main stent 10, a first bare coil 20, and a wrapper 30. The main stent 10 includes main coils 11 and a main covering film 12, and the main covering film 12 covers the main coils 11. The main coils 11 form an annular structure by connecting the heads and tails of multiple waveform units. Herein, the waveform unit refers to a single-wave structure composed of a wave crest, a wave rod, and a wave valley, and the shape of the waveform unit is not limited. Each main coil 11 can be a regular annular structure formed by multiple waveform units of the same height, or an irregular annular structure including high and low waves formed by waveform units of different wave heights. The adjacent main coils 11 can all be regular annular structures, or all be irregular annular structures including high and low waves, or a combination of a regular annular structure and an irregular annular structure including high and low waves, which is not limited herein.

[0099] The main covering film 12 is a tubular structure with openings at both ends. Multiple main coils 11 are arranged axially and connected by the tubular main covering film 12 to form the tubular main stent 10. The distal end of the first bare coil 20 is connected to the proximal end of the main stent 10, and at least part of the first bare coil 20 is exposed outside the main covering film 12.

[0100] The wrapper 30 is connected to one side of the main stent 10 or disposed around the main stent 10. The wrapper 30 releasably wraps the main stent 10 so that the main stent 10 is radially compressed or released from restraint, thereby constraining the compressed main stent 10 within the wrapper or enabling the main stent 10 to be released from the wrapper and expand naturally. In one embodiment, the wrapper can be set as the envelope 30a. In some embodiments described below, the wrapper is described by taking the envelope as an example.

[0101] As Figure 2-3 shown, the main covering film 12 includes a first film layer 121 and a linear film 122. The linear film 122 is wound circumferentially along the main covering film 12. The linear film 122 can be multiple lines wound parallel to the radial direction circumferentially along the covered stent 100, or one line or multiple lines wound spirally circumferentially along the covered stent 100. Among them, the first film layer 121 is attached to one side of the main coils 11. The linear film 122 can be disposed between the first film layer 121 and the main coils 11, can be disposed on the side of the first film layer 121 away from the main coils 11, or can be disposed on the side of the main coils 11 away from the first film layer 121, which is not limited herein. In one embodiment, the linear film 122 is disposed on the side of the main coils 11 away from the first film layer 121 and can cooperate with the first film layer 121 to thereby have a constraining effect on the main coils 11.

[0102] In one embodiment, the main body film coating 12 further includes a second film layer 123, and the second film layer 123 is attached to the side of the main body corrugated ring 11 away from the first film layer 121. The first film layer 121 is attached to the inner side of the main body corrugated ring 11, the second film layer 123 is attached to the outer side of the main body corrugated ring 11, the linear film 122 is disposed between the main body corrugated ring 11 and the second film layer 123, and the linear film 122 is spirally wound upward along the circumferential direction of the film coating support 100; the linear film 122 and the first film layer 121, the first film layer 121 and the second film layer 123, and the linear film 122 and the second film layer 123 can all be fixed together by gluing or hot pressing.

[0103] The linear film 122 can be a linear structure formed by a single strand or multiple strands of wires, and the average wire diameter range of the linear structure is: 0.05 mm to 0.3 mm. The cross-sectional area of the linear structure can be circular, elliptical, rectangular, etc. The thickness of the linear structure can be uniform or non-uniform in its extending direction, and no limitation is made here. When the cross-sectional area of the linear structure is non-circular, the thickness range of the linear structure in the radial direction of the film coating support 100 is: 0.05 mm to 0.3 mm. The linear film 122 can be made of a polymer material with good biocompatibility such as PTFE wire. In one embodiment, the linear film 122 is spirally wound along the circumferential direction of the film coating support 100, and the spiral rising angle range is 0° to 45°. For example, when the linear film 122 is spirally wound along the circumferential direction of the film coating support 100, the spiral rising angle can be 0°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, etc. The linear film 122 can be a single strand of wire spirally rising at equal intervals, or non-equal intervals; the linear film 122 can also be multiple strands of wires spirally arranged at equal intervals, or non-equal intervals, and no limitation is made here, as long as the linear film 122 bypasses each corrugated ring.

[0104] As Figure 1 shown, the main body support 10 includes opposite first side 10a and second side 10b along the circumferential direction, and it is defined that the first side 10a and the second side 10b each occupy an arc of 180° in the circumferential direction.

[0105] Combined Figure 4As shown, the envelope 30a is connected to the first side 10a of the main body stent 10. The envelope 30a and the main body stent 10 are connected by a tying wire 40. In one embodiment, the portion of the envelope 30a near the proximal end is connected to the main body stent 10 at a position near the proximal end by the tying wire; in this embodiment, the axial length of the envelope 30a is equal to the axial length of the main body covering film 12. In other embodiments, the axial length of the envelope 30a can also be approximately equal to the axial length of the main body covering film 12. Herein, "approximately equal" means that the difference ratio between the axial length of the envelope 30a and the axial length of the main body covering film 12 is less than or equal to 10%. Such that the proximal end of the envelope 30a extends at least to the central position of the main body wave ring 11 at the most proximal end, the distal end of the envelope 30a extends at least to the axial center of the main body wave ring 11 at the most distal end, and the two ends of the envelope 30a do not extend too far beyond the two ends of the main body stent 10; define the larger one of the axial length of the envelope 30a and the axial length of the main body covering film 12 as H1, and define the smaller one of the axial length of the envelope 30a and the axial length of the main body covering film 12 as H2, then the difference ratio of the two axial lengths is: (H1 - H2) / H2. In one embodiment, the envelope is rectangular, the main body covering film is a tubular film, and the axial length of the envelope is slightly larger than the axial length of the main body covering film. Then the axial length of the envelope is H1, and the axial length of the main body covering film is H2, as Figure 4-5 shown. Define the width at a certain position of the envelope 30a (the direction where this width is located is perpendicular to the axis of the covered stent 100) as W, and define the circumference at the position corresponding to the width at a certain position of the envelope 30a when the covered stent 100 is in the natural expansion state as C. Then the relationship between W and C satisfies: W ≤ C / 4, so that when the envelope 30a wraps and constrains the radially compressed covered stent 100, when limiting the axial movement of the pre-set catheter 79 within the compressed covered stent 100, the radial space where the pre-set catheter 79 can move will not be too large.

[0106] The envelope 30a has a strip-shaped structure. In one embodiment, the envelope 30a has a rectangular sheet structure, and its length direction corresponds to the axis of the main body stent 10. At least one limiting hole 31 is respectively arranged at positions near the edges of the two long sides of the envelope 30a. When multiple main body wave rings 11 are arranged along the axis, a plurality of limiting holes 31 are respectively arranged at intervals along the axis at positions near the edges of the two long sides of the envelope 30a, so as to facilitate the beam diameter guide wire 741 to pass through the limiting holes 31 on the two long sides of the envelope 30a in sequence, so that the envelope 30a encloses into a tubular body, thereby wrapping the radially compressed covered stent 100. In this embodiment, a limiting member 35 is arranged between the limiting hole 31 and the edge of the envelope 30a, which is used to prevent the membrane hole from expanding to the edge of the envelope 30a and breaking the closed state of the membrane hole, thereby avoiding the reliability of the beam diameter guide wire 741 passing through the membrane hole and enclosing the envelope 30a into a tubular body from being reduced.

[0107] As Figure 1, Figure 5 , Fig. 9 and Fig.11 As shown in Figure 5 , Fig. 9 and Fig.11 , the envelope 30a is knotted and connected to the first side 10a of the main body stent 10 by the tying thread 40. When the covered stent 100 is loaded or released, the envelope 30a may be subject to frictional force, causing relative movement between it and the main body covering film 12, so that the envelope 30a and the main body covering film 12 are pulled by the tying thread 40, which may lead to the enlargement of the film holes on the main body covering film 12 and the envelope 30a through which the tying thread 40 passes.

[0108] The envelope 30a further includes a buffer member 32, which is arranged in the middle area of the envelope 30a and extends along the plane where the envelope 30a is located. In one embodiment, the buffer member 32 can be set as a strengthening wire extending axially. The tying thread 40 passes through the film hole of the envelope 30a and straddles the buffer member 32. In other embodiments, the buffer member 32 can also be set as a strengthening wire extending transversely or obliquely. The buffer member 32 can be formed in the plane where the envelope 30a is located or on the surface of the envelope 30a by heat treatment together with the envelope 30a. The envelope 30a can be selected from PTFE film or PET film, and the material of the strengthening wire can be selected from biocompatible polymer wires such as PTFE wire. PTFE wire or film has good heat resistance, chemical inertness, self-lubrication and non-stickiness, is not easily wetted by tissue fluid, is corrosion-resistant, has the best aging life among plastics, is non-toxic, can withstand pressure, can be implanted into the human body, and can withstand a certain amount of tension and pulling force. PET film also has good physical and chemical properties and can be used as the material of the envelope 30a.

[0109] The main body stent 10 includes a tying attachment 111, which extends along the main body covering film 12. The main body covering film 12 includes a first perforation 124 and a second perforation 125, which respectively pass through the inside and outside of the main body covering film 12, and the first perforation 124 and the second perforation 125 are respectively arranged on both sides of the extending direction of the tying attachment 111. The tying attachment 111 can be set as the wave rod of a main body wave ring 11, that is, the tying attachment 111 includes a part of a main body wave ring; the tying attachment 111 can also be a tying wire arranged on the main body covering film 12, and the tying wire can be fixed to the main body covering film 12 by gluing or hot pressing. In one embodiment, the tying attachment 111 is arranged at the proximal end of the main body stent 10. The main body stent 10 includes a main body wave ring 11 arranged at the proximal end, and the tying thread 40 is connected to the wave rod or wave peak or wave valley of the main body wave ring 11, that is, the tying attachment 111 is set as the wave rod or wave peak or wave valley of the main body wave ring 11; the main body wave ring 11 is a waveform ring formed by a metal screw rod extending in a waveform along the circumference of the main body stent 10 and connecting the head and tail, and the first perforation 124 and the second perforation 125 are respectively arranged on both sides of the extending direction of the tying attachment 111.

[0110] The envelope 30a includes a third perforation 33 and a fourth perforation 34, and the third perforation 33 and the fourth perforation 34 are respectively arranged on both sides of the extending direction of the buffer member 32. In one embodiment, the tying wire 40 can pass through the first perforation 124 and the second perforation 125, cross over the tying accessory 111, then pass through the third perforation 33 and the fourth perforation 34, cross over the buffer member 32 and then tie a knot. For the main body film covering, when the tying wire 40 passes through the main body film covering 12, it crosses over the tying accessory 111. When the covered stent 100 is loaded or released, although the envelope 30a and the main body film covering 12 are pulled by the tying wire 40, the tying wire 40 mainly pulls on the tying accessory 111. When the tying wire 40 is stressed, it can reduce the possibility of the film holes of the first perforation 124 and the second perforation 125 expanding, thereby preventing endoleakage; and the setting of the buffer member 32 can enable the tying wire 40, when stressed, to mainly pull on the buffer member 32, and when the tying wire 40 is stressed, it can reduce the possibility of the film holes (at the third perforation 33 and the fourth perforation 34) on the envelope 30a expanding.

[0111] In other embodiments, the tying wire 40 passes through the first perforation 124 and the second perforation 125, crosses over the tying accessory 111 and then ties a knot, and then passes through the third perforation 33 and the fourth perforation 34, crosses over the buffer member 32 and then ties a knot; for the main body film covering, on the one hand, when the tying wire 40 passes through the main body film covering 12, it crosses over the tying accessory 111. When the covered stent 100 is loaded or released, although the envelope 30a and the main body film covering 12 are pulled by the tying wire 40, the tying wire 40 mainly pulls on the tying accessory 111. When the tying wire 40 is stressed, it can reduce the possibility of the film holes of the first perforation 124 and the second perforation 125 expanding, thereby preventing endoleakage; on the other hand, the tying wire 40 passes through the first perforation 124 and the second perforation 125, crosses over the tying accessory 111 and then ties a knot to form a break point for force conduction, which can reduce the pulling force on the main body film covering when the envelope is pulled by the tying wire, and has a certain limiting effect on the tying wire crossing over the main body film covering part, thereby further reducing the possibility of the film holes of the first perforation 124 and the second perforation 125 expanding. And the setting of the buffer member 32 can enable the tying wire 40, when stressed, to mainly pull on the buffer member 32, and when the tying wire 40 is stressed, it can reduce the possibility of the film holes (at the third perforation 33 and the fourth perforation 34) on the envelope 30a expanding.

[0112] One or more fixed connection points may be provided between the envelope 30a and the main body stent 10. The fixed connection points are connected to the positions corresponding to the binding attachments 111. In one embodiment, one fixed connection point is provided between the envelope 30a and the main body stent 10. The tying wire 40 includes a first tying wire 41. The first tying wire 41 passes through the first perforation 124 and the second perforation 125 on the main body film 12 and at the same time straddles a binding attachment 111. The two wire ends of the first tying wire 41 are located outside the main body stent 10. At this time, one or two wire knots may be tied outside the main body stent 10. The wire knot is finally formed between the envelope 30a and the main body stent 10. Subsequently, the first tying wire 41 passes through the third perforation 33 and the fourth perforation 34 of the envelope 30a and is knotted on the side of the envelope 30a away from the main body stent 10 to prevent the tying wire 40 from loosening, and at the same time, the knot of the tying wire 40 is formed outside the lumen of the covered stent 100 to avoid affecting the blood flow in the lumen. In other embodiments, such as Figure 5 shown, two fixed connection points may also be provided between the envelope 30a and the main body stent 10. The tying wire 40 further includes a second tying wire 42. The second tying wire 42 can be fixedly connected to the perforations on the envelope 30a and the covered stent 100 in the same manner as the first tying wire 41, which will not be elaborated here.

[0113] In one embodiment, in combination with Figure 5-6 shown, the first tying wire 41 is connected to the wave rod of the main body wave ring 11. At least one linear film 122 is provided on each of the proximal side and the distal side of the tying wire 40 to limit the expansion of the first perforation 124 and the second perforation 125 toward the proximal side and the distal side. The shortest distance L1 from a linear film 122 to the edge of the first perforation 124 in the axial direction satisfies: L1 ≤ 3 mm. The shortest distance L2 from a linear film 122 to the edge of the second perforation 125 in the axial direction satisfies: L2 ≤ 3 mm. In other embodiments, the first tying wire 41 may be connected to the wave crest of the main body wave ring 11. At least one linear film 122 is provided on the distal side of the first tying wire 41 to limit the expansion of the perforation passing through the main body film 12 on the inner side of the wave crest bending; the first tying wire 41 may also be connected to the wave trough of the main body wave ring 11. At least one linear film 122 is provided on the proximal side of the first tying wire 41 to limit the expansion of the perforation passing through the main body film 12 on the inner side of the wave trough bending. In other embodiments, the two ends of the main body wave ring are wrapped by a steel sleeve to make the main body wave ring into a closed waveform ring. The tying wire may also be connected to the main body wave ring and near the edge of the steel sleeve, so as to use the steel sleeve to limit the relative movement of the tying wire with respect to the main body film.

[0114] Such as Figure 7-8As shown, the main body wave loop 11 is formed by sequentially connecting multiple single waves. The main body bracket 10 includes a main body wave loop 11 disposed at the proximal end of the covered stent 100. The main body wave loop 11 includes a first wave peak 1111, a first wave valley 1112, and a first wave rod 1113 connecting the first wave peak 1111 and the first wave valley 1112. The first wave rod 1113 serves as the tying attachment 111. The first through hole 124 and the second through hole 125 are respectively disposed on both sides of the extending direction of the first wave rod 1113. Define the straight line connecting the geometric centers of the holes of the first through hole 124 and the second through hole 125 as W1, define the intersection point of W1 and the first wave rod 1113 as Q, and define the tangent line passing through point Q and tangent to the wave rod as W2. The included angle α between W1 and W2 satisfies: 60° ≤ α ≤ 90° (the included angle range of two straight lines is 0° to 90°). When the perpendicular distances from the first through hole 124 and the second through hole 125 to the first wave rod 1113 are both constant, if the included angle between W1 and W2 is too small, the line segment connecting the first through hole 124 and the second through hole 125 is too long. When the first tying wire 41 is subjected to a pulling force, it is not convenient to apply the main pulling force to the wave rod of the main body wave loop 11, reducing the force on the edge of the membrane hole, which may cause the membrane hole to expand.

[0115] In one of the embodiments, the linear membrane 122 includes a first linear membrane 122a and a second linear membrane 122b. The first linear membrane 122a is disposed on the proximal end side of the first through hole 124 and the second through hole 125. The second linear membrane 122b is disposed on the distal end side of the first through hole 124 and the second through hole 125. The included angle β1 between the first linear membrane 122a and W1 satisfies: 0° ≤ β1 ≤ 20°, so as to facilitate the first linear membrane 122a to set a limit on the proximal end side of the first through hole 124 and the second through hole 125, avoiding the possibility of the membrane holes of the first through hole 124 and the second through hole 125 expanding towards the proximal end side; the included angle β2 between the second linear membrane 122b and W1 satisfies: 0° ≤ β2 ≤ 20° (in order to facilitate the identification of β1 and β2, the included angle between the linear membrane 122 and the parallel line of W1 is marked in the figure), so as to facilitate the second linear membrane 122b to set a limit on the distal end side of the first through hole 124 and the second through hole 125, avoiding the possibility of the membrane holes of the first through hole 124 and the second through hole 125 expanding towards the distal end side.

[0116] The covered stent 100 can be used for implantation in a curved blood vessel. When the covered stent 100 is in the implanted form in the curved blood vessel, the first side 10a of the main stent 10 is defined as the side that fits the small curvature side of the blood vessel, and the second side 10b of the main stent 10 is defined as the side that fits the large curvature side of the blood vessel. Taking the curved form of the main stent 10 implanted in the aortic arch as an example, the first side 10a and the second side 10b of the main stent 10 are further described. Among them, the first side 10a is the side of the main stent 10 away from the aortic arch branches (small curvature side), and the second side 10b is the side of the main stent 10 close to the aortic arch branches (large curvature side).

[0117] As Figure 9-12 shown, the covered stent 100 may further include a branch stent 50. The branch stent 50 is connected to one axial side of the main stent 10, and the lumen of the branch stent 50 is communicated with the lumen of the main stent 10. In this embodiment, as Fig. 9 shown, the envelope 30a is connected to the first side 10a of the main stent 10, the branch stent 50 is connected to the second side 10b of the main stent 10, and the branch stent 50 can be arranged at the arc middle position of the second side 10b; combined with Fig.13 shown, the main stent 10 further includes a plurality of connecting members 16. The connecting members 16 connect two adjacent main stent loops 11. The connecting members are arranged on the second side 10b of the main stent 10. The connecting members can be formed by one end of a main stent loop 11 extending to an adjacent main stent loop 11, or a plurality of separate connecting members can axially connect two adjacent main stent loops 11 together. The connecting members 16 are continuously arranged along the axial direction at the circumferential center of the second side 10b. The branch stent 50 is arranged on the circumferential central axis of the second side 10b, and some connecting members 16 and the branch stent 50 are arranged on the same axial line, so that the covered stent 100 is convenient to bend towards the first side 10a and not convenient to bend towards the second side 10b; the connecting members 16 near the branch stent 50 can be arranged on both axial sides of the branch stent 50 to avoid the position of the branch stent 50.

[0118] The main stent loops 11 include high and low loops. When the covered stent 100 is placed in a curved blood vessel, the high and low loops are arranged at the bending part of the covered stent 100. In this embodiment, the main stent loops 11 include a plurality of high and low loops. The high and low loops include a plurality of continuous short-wave single loops arranged on the first side 10a and a plurality of continuous high-wave single loops arranged on the second side 10b. The axial distance between the short waves of adjacent high and low loops is relatively large, so that when the covered stent 100 is implanted in a curved blood vessel, it is convenient to bend towards the first side 10a.

[0119] As Fig. 9As shown, the main stent 10 successively includes a proximal end segment 10c, a bending segment 10d, and a distal end segment 10e from the proximal end to the distal end. That is, the bending segment 10d is closer to the distal end than the proximal end segment 10c. The flexibility of the first side 10a of the proximal end segment 10c is less than that of the first side 10a of the bending segment 10d, and the flexibility of the first side 10a of the distal end segment 10e is less than that of the first side 10a of the bending segment 10d, so that the bending segment 10d is more likely to bend towards the first side 10a (here, the flexibility refers to the characteristic that the covered stent 100 is more likely to bend, which can be set by adjusting the interval distance between adjacent corrugations. The flexibility is greater at the position where the interval distance between adjacent corrugations is larger; it can also be adjusted by setting connecting members, and the flexibility is smaller at the position where the connecting members are set).

[0120] As Fig.10 shown, when the covered stent 100 is implanted into a curved blood vessel, the bending segment 10d bends towards the first side 10a, causing the bending segments 10d on the first side 10a to stack. Since the envelope 30a is arranged on the first side 10a, if no fixed connection point is set on the proximal end segment 10c of the envelope 30a, after the covered stent 100 is released, due to the stacking of the bending segments 10d, the proximal side edge of the envelope 30a seriously exceeds the proximal side of the main body covering film 12, thus affecting the blood flow at the inflow end of the covered stent 100 and causing unnecessary risks.

[0121] As Fig. 9 and Fig.11 Combined with Figure 5 shown, the tying accessory 111 includes a first tying accessory 111a and a second tying accessory 111b. The first tying accessory 111a is closer to the proximal end of the main stent 10 than the second tying accessory 111b. The envelope 30a is connected to the main stent 10 at the first tying accessory 111a through the first tying wire 41 and at the second tying accessory 111b through the second tying wire 42, thereby connecting the envelope 30a to the main stent 10. In one embodiment, as Fig.11 Combined with Figure 5 shown, the first tying accessory 111a is arranged on the first side 10a of the proximal end segment 10c. Since when the covered stent 100 is implanted into a curved blood vessel, the position change of the proximal end segment 10c only changes due to conforming to the bending of the bending segment 10d, and its own bending is small, that is, the stacking on the first side 10a of the proximal end segment 10c is less. Then, the edges between the main body covering film 12 from the perforation position corresponding to the first tying accessory 111a to the proximal end part and the corresponding part of the envelope 30a can remain flush before and after implantation, thereby preventing the proximal side edge of the envelope 30a from seriously exceeding the proximal side of the main body covering film 12 and avoiding affecting the blood flow at the inflow end of the covered stent 100, as Fig.12As shown. That is, at least one binding attachment 111 is provided on the first side 10a of the proximal end segment 10c, so that at least one fixed connection point is provided between the package and the main body bracket at the proximal end segment, so that the relative position between the part of the envelope 30a from the position of this fixed connection point to the proximal end side and the main body bracket 10 of the corresponding proximal end segment 10c is almost unchanged before and after implantation, so as to avoid the situation that after implantation into a curved blood vessel, the proximal end side edge of the envelope 30a seriously exceeds the proximal end side of the main body membrane 12 due to the stacking on the first side 10a of the curved segment 10d.

[0122] In the present embodiment, as Fig.11 shown, the proximal end segment 10c sequentially includes a first main body wave ring 11a and a second main body wave ring 11b from the proximal end to the distal end. The first main body wave ring 11a is an equal-height small wave ring with a smaller wave height relative to other main body wave rings 11. The second main body wave ring 11b can be an equal-height small wave ring. The distal end portion of the proximal end segment 10c is the circumferential surface where the wave trough of the second main body wave ring 11b is located; the second main body wave ring 11b can also be a high-low wave ring with the proximal end wave peaks flush, and the first side 10a of the second main body wave ring 11b is a low wave, and the second side 10b is a high wave. Then, the distal end portion of the proximal end segment 10c is the circumferential surface where the wave trough of the low wave of the first side 10a of the second main body wave ring 11b is located.

[0123] The curved segment 10d sequentially includes a third main body wave ring 11c and a fourth main body wave ring 11d from the proximal end to the distal end. Among them, both the third main body wave ring 11c and the fourth main body wave ring 11d are high-low wave rings. The third main body wave ring 11c can be a nearly flat high-low wave ring or a far flat high-low wave ring, and the fourth main body wave ring 11d can also be a nearly flat high-low wave ring or a far flat high-low wave ring, so as to ensure that the axial distance between adjacent wave rings on the first side 10a of the curved segment 10d is relatively larger than the distance between adjacent wave rings of the proximal end segment 10c or the distal end segment 10e, so as to ensure the flexibility of the first side 10a of the curved segment 10d and make the curved segment 10d of the covered stent 100 more likely to bend towards the first side 10a; among them, the nearly flat high-low wave ring means that the wave peaks of the high wave and the low wave on the proximal end side are flush, and the far flat high-low wave ring means that the wave troughs of the high wave and the low wave on the distal end side are flush.

[0124] In the present embodiment, the third main body wave ring 11c is a nearly flat high-low wave ring, the fourth main body wave ring 11d is a far flat high-low wave ring, and the axial distance d1 between the wave trough on the first side 10a of the first main body wave ring 11a and the wave peak on the first side 10a of the second main body wave ring 11b is less than the axial distance d2 between the low wave trough on the first side 10a of the second main body wave ring 11b and the low wave peak on the first side 10a of the third main body wave ring 11c; in the present embodiment, the first binding wire 41 is arranged on the wave rod or wave peak or wave trough on the first side 10a of the first main body wave ring 11a, and the second binding wire 42 is arranged on the wave rod or wave peak or wave trough on the first side 10a of the second main body wave ring 11b, as Figure 7-7b As shown, among them, the first main body wave loop 11a and the second main body wave loop 11b are the main body wave loops 11 for connecting with the tying wire 40; in other embodiments, the first tying wire 41 is arranged on the wave rod or wave peak or wave trough on the first side 10a of the first or second main body wave loop 11b, and the second tying wire 42 is arranged on the wave rod or wave peak or wave trough on the first side 10a of the third or fourth main body wave loop 11d. At this time, the third main body wave loop 11c connected to the first tying wire 41 includes a tying accessory 111, and the third or fourth main body wave loop 11d connected to the second tying wire 42 also includes a tying accessory 111; it is only necessary to ensure that at least one connection position is provided on the first side 10a of the proximal end section 10c for the tying wire 40 to be fixedly connected, so that the relative position between the part of the envelope 30a from the connection position to the proximal end side and the main body support 10 of its corresponding proximal end section 10c is almost unchanged before and after implantation, thereby avoiding the situation that after being implanted into a curved blood vessel, the proximal side edge of the envelope 30a seriously exceeds the proximal side of the main body covering film 12 due to the stacking on the first side 10a of the curved section 10d.

[0125] When only one fixed connection point is provided between the envelope 30a and the main body support 10, such as Figure 1 As shown, since the connection between the envelope 30a and the main body support 10 is a point connection, after the covered stent is released, the envelope 30a may swing relative to the two axial sides with the fixed connection point as the center relative to the main body support 10. The envelope 30a is too free to move relative to the covered stent. When the beam diameter releasable member 74 is withdrawn and released to release the covered stent 100 wrapped by it, since the axial direction of the envelope (the extending direction of its long side when it is rectangular) is consistent with the axial direction of the covered stent before the envelope 30a wraps the covered stent 100, and the axial direction of the released envelope 30a is deflected relative to the axial direction of the covered stent 100, it will cause the corners at both ends of the released envelope 30a to possibly exceed the proximal end of the covered stent 100 too much, thereby affecting the blood flow flowing in from the proximal end.

[0126] Such as Figure 13-16 As shown, before loading the covered stent 100 with the envelope 30a into the sheath, it is necessary to first wrap the main body support 10 with the envelope 30a. For the method of wrapping the main body support 10 with the envelope 30a, auxiliary sleeves (the first auxiliary sleeve 84, the second auxiliary sleeve 85) need to be used. Among them, the outer diameter of the auxiliary sleeve is smaller than the width of the envelope, so that when the main body support 10 is loaded into the auxiliary sleeve, the envelope 30a can be wrapped on the outer surface of the auxiliary sleeve, and at the same time, the beam diameter releasable member 74 can be easily passed through the limiting hole 31 and then the sleeves are withdrawn from both ends, so as to realize the wrapping of the main body support 10 by the envelope 30a. For the covered stent with only one fixed connection point, the main body support 10 includes a first part 101 and a second part 102, with the fixed connection point between the envelope 30a and the first tying wire 41 of the main body support 10 as the boundary ( Fig.13 Taking the vertical dotted line in the middle (as shown) as the boundary, the main stent 10 is divided into a first part 101 extending from the fixed connection point towards the proximal end and a second part 102 extending from the fixed connection point towards the distal end. Then, two auxiliary sleeves are required. The method of wrapping the main stent 10 with the envelope 30a is as follows Figure 13-16 shown. First, as Fig.13 shown, the first part 101 is inserted into an auxiliary sleeve 84 from the proximal end side until the end of the auxiliary sleeve is close to the fixed connection point. The second part 102 is inserted into another auxiliary sleeve 85 from the distal end side until the end of the auxiliary sleeve is close to the fixed connection point. And due to the existence of the envelope 30a, neither of the auxiliary sleeves can cross the binding wire at the fixed connection point position, as Fig.14 shown; then the envelope 30a is wrapped around the outer surface of the sleeve, and at the same time, the diameter-reducing releasable member 74 is passed through the limiting hole 31 to realize the radial compression wrapping of the main stent 10 by the envelope 30a, as Fig.15 shown; finally, as Fig.16 shown, the auxiliary sleeves are withdrawn, and the covered stent wrapped by the envelope 30a can be successfully loaded into the sheath of the delivery device.

[0127] Due to the above method of wrapping the main stent 10 with the envelope 30a, when two or more fixed connection points are set, taking the setting of two fixed connection points as an example, if the axial distance between the two fixed connection points (the suture positions of the two binding wires) is too close, the limiting effect of the envelope on the main stent is not good. If the axial distance between the two fixed points is too far, it is not convenient to wrap the envelope around the main stent, as Fig.17 shown, the covered stent is provided with a first binding wire 41 and a second binding wire 42. Since neither of the auxiliary sleeves at both ends can cross the binding wire at the fixed connection point, the part of the main stent between the first binding wire 41 and the second binding wire 42 cannot be constricted by the auxiliary sleeve. Therefore, this part of the main stent cannot be successfully wrapped by the envelope, that is, it is very difficult for the diameter-reducing releasable member 74 to pass through the limiting hole 31 at the corresponding position of this part, resulting in difficulty in radially compressing and wrapping the main stent by the envelope, thus causing difficulty in loading the covered stent.

[0128] Based on the above problems, a fixed connection point can be set first, and the envelope is fixed to the main stent by using the first binding wire 41. Then, after the envelope of the covered stent is wrapped around the main stent, the second fixed connection point is sutured by using the second binding wire. In one of the embodiments, as Fig.18 Combined with Figure 8As shown, the first tying thread 41 is disposed on a wave rod or a wave crest or a wave trough of a main body wave loop on a first side 10a, and the first tying thread is connected to an intermediate one-third region in a direction perpendicular to the axial direction of the envelope. The first tying thread 41 can pass through a first perforation and a second perforation disposed on the first side and straddle a first tying accessory, and then pass through a third perforation and a fourth perforation and straddle a buffer member and then tie a knot. The covered stent further includes a second tying thread 42. Since the envelope 30a wraps around the main body stent 10 and radially compresses the main body stent 10, the main body covered film 12 folds and agglomerates together, and it is not easy to distinguish the position of the proximal end side of the main body covered film 12 in the circumferential direction. At this time, when the envelope is sutured to the main body stent by using the second tying thread 42, the suturing position of the second suture 42 on the envelope 30a and the suturing position on the main body covered film are not easy to determine, and the second suture 42 may be used to suture the envelope to the circumferential opposite side of the target position on the main body stent, thereby causing a release problem of the proximal end of the main body stent 10.

[0129] As Figure 18-22 shown, the covered stent 100 includes a first positioning member Y and a second positioning member 36. The first positioning member Y is disposed at the proximal end of the main body stent 10, and the second positioning member 36 is disposed at the proximal end of the envelope. When the covered stent is in a natural expansion state, when the envelope naturally adheres to the main body stent in the circumferential direction, the first positioning member and the second positioning member are substantially on the same radial line. Among them, "the first positioning member and the second positioning member are substantially on the same radial line" means that: the first positioning member and the second positioning member 36 are on the same radial line, or the deflection angle δ of the first positioning member and the second positioning member in the circumferential direction is less than or equal to 30°. As Fig.19 shown, it is only necessary to ensure that when the first positioning member and the second positioning member 36 of the radially compressed covered stent 100 are sutured together, it will not cause excessive folding of the envelope 30a after the covered stent 100 is released, and it will not cause the envelope 30a to be sutured to the circumferential opposite side of the corresponding main body stent 10 of the envelope and affect the release of the main body stent 10. The so-called natural adhesion here means that: the envelope adheres to the main body stent without tension and without folding. As Fig.19 shown.

[0130] As Fig. 20 Combined Figure 8As shown, in one embodiment, the second tying thread 42 can be sutured at a position axially corresponding to the fixed connection point of the first tying thread 41. The axial line passing through the first perforation 124 is defined as the first axial line N1, the axial line passing through the second perforation 125 is defined as the second axial line N2, the axial line passing through the third perforation 33 is defined as the third axial line N3, and the axial line passing through the fourth perforation 34 is defined as the fourth axial line N4. The first positioning member is located between the first axial line and the second axial line. The first positioning member can be set as the second tying thread 42 or the first positioning member is set as a mark (e.g., a distinguishable shape developing structure) for indicating the position where the second tying thread 42 is sutured on the main body film 12. The second tying thread 42 passes through the inside and outside of the proximal end of the main body film 12. When suturing the envelope 30a to the main body stent 10 using the second tying thread 42, it can be avoided that the suturing position of the second tying thread 42 on the envelope 30a does not correspond to the suturing position on the main body film 12, or even the second tying thread 42 is sutured to the circumferential opposite side of the target position on the main body stent, thereby avoiding the release problem at the proximal end of the main body stent 10.

[0131] Combined Fig.19 As shown, the covered stent further includes a second positioning member 36. The second positioning member 36 is used to indicate the position where the second tying thread 42 is sutured at the envelope 30a. The second positioning member 36 is arranged at the proximal end of the envelope and is on the same radial line as the first positioning member, or the deflection angle δ of the first positioning member and the second positioning member 36 in the circumferential direction is less than or equal to 30°. In one embodiment, as Fig. 20 shown, the second positioning member 36 can be located between the third axial line N3 and the fourth axial line N4; as Fig.20a shown, the second positioning member 36 can be set as a developing ring. The second tying thread 42, as the first positioning member, has been sutured to the corresponding position on the main body film 12 and has not been sutured on the envelope 30a. After the envelope 30a is wrapped around the main body stent 10 using an auxiliary cannula, the second positioning member 36 is used to position the suturing position of the second tying thread 42 on the envelope 30a, so as to suture the second tying thread 42 at the position of the second positioning member 36. In other embodiments, the second tying thread 42 can also be sutured at a position that does not axially correspond to the fixed connection point of the first tying thread, as long as it is ensured that the first positioning member and the second positioning member are on the same radial line, or the deflection angle δ of the first positioning member and the second positioning member in the circumferential direction is less than or equal to 30°, so that the first positioning member and the second positioning member are generally on the same radial line without affecting the release of the covered stent.

[0132] In other embodiments, as Fig. 20 and 20bAs shown in the figure, the second positioning member 36 can also be set as a protrusion 361, which protrudes from the proximal end face of the main body film 12. After the wrapping film 30a wraps the main body stent 10, it is convenient to suture the second tying thread 42 onto the protruding protrusion 361, thereby avoiding the problem that when the main body stent 10 is wrapped by the wrapping film 30a, since the wrapping film 30a overlaps with the main body stent 10 and the wrapping film 30a tightly wraps the main body film 12, it is inconvenient to suture the second tying thread 42 on the wrapping film.

[0133] The present invention also provides a manufacturing method of a stent system. As Figure 21-22 shown, taking the second tying thread 42 as the first positioning member and the second positioning member being set as a protrusion as an example, the manufacturing method of this stent system is described as follows:

[0134] Provide a covered stent, and the wrapping film of the covered stent and the main body stent are fixed by a first tying thread 41;

[0135] A first positioning member (second tying thread 42) is arranged at the proximal end of the main body film 12, and a second positioning member 36 is arranged at the proximal end of the wrapping film 30a. The main body stent 10 is sleeved on the sheath core assembly of the delivery device (not shown in the figure), then the first part 101 of the main body stent 10 is radially compressed and loaded into the first auxiliary sleeve 84, the second part 102 of the main body stent is radially compressed and loaded into the second auxiliary sleeve 85, and then the wrapping film 30a is wrapped around the outer surface of the auxiliary sleeve. At the same time, the diameter-reducing releasable member 74 axially passes through the limiting hole 31 of the wrapping film to realize the radial compression wrapping of the wrapping film 30a on the main body stent 10;

[0136] Withdraw the auxiliary sleeve, suture the first positioning member (second tying thread 42) to the second positioning member (protrusion 361), and load the sutured covered stent into the sheath of the delivery device to complete the loading of the covered stent into the sheath and form a stent system.

[0137] When the main body stent is sleeved on the sheath core assembly of the delivery device, it also includes loading the first bare wave ring into the post-release structure of the delivery device, which will not be elaborated here. For a covered stent including a branch stent, before loading the main body stent into the auxiliary sleeve, it also includes threading a preset catheter through the distal end of the main body stent and out through the branch stent, and the diameter-reducing releasable member 74 can avoid the preset catheter when passing through the limiting hole.

[0138] As Figure 23-24a shown, the main body stent 10 includes an annular support member 13 and a window. The window is arranged on the side of the main body stent 10 and is used to communicate with the branch stent 50. The annular support member 13 is arranged along the window and is made of a radiopaque material, which is used to support the edge of the window and at the same time display the position where the branch stent 50 is located.

[0139] The branch stent 50 includes a first end 51, an intermediate section 52, and a second end 53. The first end 51 and the second end 53 are opposite ends, and the intermediate section 52 is disposed between the first end 51 and the second end 53. The covered stent 100 further includes an annular connecting membrane 14. The annular connecting membrane 14 connects the main body stent 10 and the intermediate section 52 of the branch stent 50, thereby connecting the branch stent 50 to the main body stent 10, and causing the first end 51 of the branch stent 50 to be located inside the lumen of the main body stent 10, and the second end 53 of the branch stent 50 to be located outside the lumen of the main body stent 10, as Figure 24-24a shown.

[0140] The outer diameter of the branch stent 50 is smaller than the inner diameter of the annular support member 13, and the radial width of the annular connecting membrane 14 is greater than the difference between the inner diameter of the annular support member 13 and the outer diameter of the branch stent 50, so that the annular connecting membrane 14 allows the branch stent 50 to float up and down (in the radial direction of the main body stent 10), and at the same time, the branch stent 50 can swing 360° along its tubular circumference, so that the opening of the second end of the branch stent 50 away from the main body stent 10 is adjustable. After the covered stent 100 is implanted into the blood vessel, when using a guide wire towards the branch blood vessel access, the opening of the second end of the branch stent 50 is more likely to be aligned with the branch blood vessel opening, and the influence of reducing the anatomical complexity on the correspondence between the opening of the second end of the branch stent 50 and the branch blood vessel opening is reduced. The annular connecting membrane connects the middle part of the branch stent 50, so that a part of the branch stent 50 is located outside the main body stent 10 and a part is located inside the main body stent 10, which can ensure that the second end of the branch stent 50 floats down to be flush with the main body stent 10, and within the range of the annular support member, the orientation of the opening of the second end of the branch stent 50 is adjustable, which is more convenient to adapt to different anatomical forms.

[0141] The present invention also provides a stent system 700, as Fig.25 shown in combination Figure 30-32 The stent system 700 includes the above-mentioned covered stent 100 and a delivery device 70. The delivery device 70 includes a sheath core assembly 71, a support rod 72, a sheath tube 73, a beam diameter releasable member 74, and a handle assembly 75. The sheath core assembly 71 includes an inner sheath core 711 and an outer sheath core 712. The inner sheath core 711, the outer sheath core 712, the support rod 72, and the sheath tube 73 are sleeved in sequence from the inside to the outside, and the inner sheath core 711, the outer sheath core 712, and the sheath tube 73 can move relative to each other axially in pairs. The support rod 72 is sleeved outside the sheath core assembly 71. The delivery device 70 further includes a guiding head 76. The guiding head 76 is disposed at the distal end of the inner sheath core 711. There is a space interval between the distal end of the support rod 72 and the proximal end of the guiding head 76 to form a loading space for the covered stent 100, as Fig.25 shown. To facilitate the display of the structure inside the sheath tube 73, this figure shows the internal components of the sheath tube 73.

[0142] As Figure 26-26aAs shown, the support rod 72 includes a first channel 721 and a second channel 722 that penetrate axially. The first channel 721 allows the sheath core assembly 71 to pass through axially, and the second channel 722 allows the beam diameter guide wire 741 to pass through axially, as Fig.26 shown. In other embodiments, the support rod 72 may further include a third channel 723 that allows the pre-set catheter 79 to pass through axially, as Fig.26a shown.

[0143] As Fig. 27 combined Fig.25 shown, the beam diameter releasable member 74 may include a beam diameter guide wire 741. The distal end of the beam diameter releasable member 74 is sutured to the limiting holes 31 along the two long side edges of the envelope 30a so as to facilitate the opening of the envelope 30a to release the stent. The proximal end of the beam diameter releasable member 74 is connected with a safety buckle 743, and the safety buckle 743 is detachably fixed on the handle assembly 75 to prevent the misplacement of the covered stent 100.

[0144] As Fig. 27 shown, the beam diameter guide wire 741 is used to sequentially pass through the holes near the edges of the two long sides of the envelope 30a axially, so as to wrap the covered stent 100 in the envelope 30a, radially compress the covered stent 100 in the envelope 30a, and make the covered stent 100 in a radially compressed beam diameter state. The distal end of the beam diameter guide wire 741 is used to sequentially cross through the limiting holes 31 provided at the edges of the two long sides of the envelope 30a axially, so as to enclose the envelope 30a into a tubular body, thereby radially compressing and bundling the covered stent 100 in the envelope 30a, and the restriction of the beam diameter guide wire 741 on the limiting holes 31 can be released by retracting the beam diameter guide wire 741 backward, so as to release the covered stent 100 from the compressed state and relieve the restraint of the envelope 30a on the covered stent 100. The proximal end of the beam diameter guide wire 741 is connected with a pull ring buckle as the safety buckle 743, and the pull ring buckle is detachably fixed on the handle assembly 75. When it is necessary to release the covered stent 100, first release the safety buckle 743 from the handle assembly 75, and then pull the safety buckle 743 backward. The envelope 30a opens, relieving the radial restraint on the covered stent 100 and allowing the covered stent 100 to expand naturally.

[0145] As Fig. 27As shown, the stent system 700 further includes a branch sheath 77. The branch sheath 77 includes a wrapping portion 771, a hooking portion 772, and a branch guide wire 773. The wrapping portion 771 is used to wrap the branch stent 50. The wrapping portion 771 is provided as a wrapping film with one end open and one end sealed. And the end of the wrapping portion 771 close to the main body stent 10 is an open structure, while the end of the wrapping portion 771 away from the main body stent 10 is a closed structure. The hooking portion 772 is disposed at the end of the wrapping portion 771 close to the main body stent 10, and the branch guide wire 773 is disposed at the end of the wrapping portion 771 away from the main body stent 10. The hooking portion 772 includes a loop wire for the beam diameter guide wire 741 or the detachable suture structure 742 to pass through, so that the branch sheath 77 is fixedly connected to the main body stent 10 until the main body stent 10 is released after the envelope 30a is opened. The branch guide wire 773 is used to assist the branch stent 50 of the covered stent 100 to accurately align with the branch vessel orifice.

[0146] In other embodiments, as Figure 28-29 shown, the beam diameter detachable member 74 may also include a detachable suture structure 742. The detachable suture structure 742 axially passes through the holes at the edges near the two long sides of the envelope 30a to radially compress the covered stent 100 within the envelope 30a. The beam diameter detachable member 74 is not limited herein, as long as it can cooperate with the envelope 30a to achieve radial constriction and release of the covered stent 100. As Fig.28 shown, the detachable suture structure 742 includes a constraint section 7421 and a lead section 7422. The constraint section 7421 axially stitches the edges of the two long sides of the envelope 30a to form the envelope 30a into a tubular structure, so as to constrict the radially compressed covered stent 100 within the envelope 30a. The lead section 7422 is formed by the part of the constraint section 7421 extending outside the envelope 30a. Pulling the lead section 7422 can release the constraint of the constraint section 7421 on the two long sides of the envelope 30a, causing the envelope 30a to open and releasing the radial constriction of the covered stent 100, as Fig.29 shown.

[0147] In other embodiments, the branch sheath 77 may not be provided, and a pre-embedded guide wire (not shown in the figure) may be provided. The support rod 72 includes a channel for the pre-embedded guide wire to axially pass through. Then, the pre-embedded guide wire is used to select the branch vessel orifice. Since it is difficult for a single guide wire to directly select the branch vessel orifice, the pre-embedded guide wire can be captured by a guide wire catcher to enter the branch vessel.

[0148] One end of the branch guide wire 773 can be pulled out of the body along the branch blood vessel by establishing a branch access path in advance for the branch guide wire 773 to pass through by utilizing a guide wire along the branch or by capturing the branch guide wire 773 from the distal end of the delivery device 70 with a wire snare (not shown in the figure), so that the branch stent 50 can be accurately positioned at the branch blood vessel orifice. After the covered stent 100 is accurately released, if necessary, an external extension stent 90 can be implanted. One end (close to the branch stent 50) of the extension stent 90 (not shown) is sleeved inside the branch stent 50, and the other end (far from the branch stent 50) of the extension stent 90 is placed inside the branch blood vessel.

[0149] As Fig.25 shown, the handle assembly 75 includes a fixed handle 751, a sliding handle 752 and a wing portion 753. The proximal end of the fixed handle 751 includes a guide rail 7511 extending towards the proximal end. The proximal end of the sheath 73 is connected inside the sliding handle 752. The sliding handle 752 is arranged on the proximal side of the fixed handle 751 around the guide rail 7511, so that the sliding of the sliding handle 752 along the guide rail 7511 can drive the sheath 73 to retract, facilitating the release of the lumen stent from the distal end of the sheath 73. The wing portion 753 is arranged on the proximal side of the catheter. A channel is provided inside the wing portion 753 and is communicated with the channel inside the support rod 72 for the pre-set catheter to pass through, facilitating the operation of the pre-set catheter.

[0150] As Figure 30-32As shown, the conveyor 70 further includes a rear release structure for hooking the first bare coil 20, thereby realizing the rear release of the first bare coil 20 at the proximal end of the covered stent 100. The conveyor 70 includes a clamping member 78 connected to the distal end of the outer sheath core 712; the clamping member 78 includes a plurality of clamping claws 781 and a connecting portion 782, and a clamping portion 761 and a clamping groove 762 are provided at the proximal end of the guiding head 76; the plurality of clamping claws 781 radiate and disperse from the connecting portion 782 towards the distal end, and the connecting portion 782 fixes the plurality of clamping claws 781 to the distal end of the outer sheath core 712, wherein the plurality of clamping claws 781 can be respectively matched with the clamping grooves 762 one by one; the clamping portion 761 is arranged on one side of the distal end of the clamping groove 762, the clamping portion 761 includes a clamping surface 7611 and a clamping step 7612, the inner peripheral surface of the sheath tube 73 is sleeved on the clamping surface 7611, and the distal end face of the sheath tube 73 abuts against the clamping step 7612, so as to facilitate the guiding head 76 to be fitted and embedded into the distal end of the sheath tube 73, and at the same time, the matching part of the clamping claw 781 and the clamping groove 762 is received into the sheath tube 73. It can be understood that the cooperation between the clamping member 78 and the clamping groove 762 forms the above-mentioned releasable rear release structure, that is, the rear release structure includes the clamping member 78 and the clamping groove 762, the closable state formed by the cooperation and clamping of the clamping member 78 and the clamping groove 762, and the open state formed by the mutual separation of the clamping member 78 and the clamping groove 762. When in the closable state, the rear release structure can temporarily fix the first bare coil 20 at the proximal end of the covered stent 100 before rear release.

[0151] Taking the method of using a guide wire along the branch to establish a branch access in advance for the branch guide wire 773 to pass through as an example, the surgical method of using the stent system 700 provided by this embodiment for aortic arch implantation is briefly described as follows:

[0152] Import the guide wire (not shown in the figure) along the branch vessel access, from the proximal end to the distal end of the aorta, and finally export it from the femoral artery incision, then penetrate the guiding catheter 81 along the guide wire from the branch vessel access and export it from the femoral artery, and then withdraw the guide wire, thereby forming a guiding catheter 81 access as shown in Fig.33 shown.

[0153] Import the super-stiff guide wire 82 into the ascending aorta, import the stent system 700 along the super-stiff guide wire 82, the stent system 700 is slowly imported into the human body along the super-stiff guide wire 82, and at the same time, the branch guide wire 773 in the stent system 700 is imported from the femoral artery into the branch vessel along the guiding catheter 81, pull out the branch guide wire 773 from the guiding catheter 81, and cooperate with pulling the branch guide wire 773 and the guiding catheter 81 to import the distal end of the stent system 700 to a straight section near the arch, as shown in Fig.34 shown.

[0154] Continue to push the stent system 700 along the super-stiff guide wire 82 so that the distal end of the stent system 700 is delivered to the aortic arch for the preliminary positioning of the stent system 700. Withdraw the sheath 73 of the delivery device 70 to the distal end of the main stent 10, so that the covered stent 100 constricted by the envelope 30a is completely exposed. Since the covered stent 100 is radially constricted by the envelope 30a, after the sheath 73 is withdrawn, the stent system 700 can still be adjusted along the super-stiff guide wire 82 to accurately position the covered stent 100. The branch stent 50 is exposed after the sheath 73 is withdrawn. At this time, pull the branch guide wire 773 and push and adjust the main stent 10. With the auxiliary traction of the branch guide wire 773, the branch stent 50 is pulled into the branch blood vessel. Since the proximal end of the branch guide wire has a loop wire (hooking part 772) and the diameter-reducing guide wire 741 hooked to each other, a certain external force can be used to make the branch opening of the covered stent 100 accurately align with the branch blood vessel through the traction force of the branch guide wire 773, as Figure 35-36 shown.

[0155] As Figure 37-38 shown, pull the diameter-reducing guide wire 741 of the stent system 700 or the lead segment 7422 of the suture structure backward, and the main stent 10 unfolds and adheres to the wall in sequence from the proximal end to the distal end. Completely withdraw the diameter-reducing guide wire 741 or the suture structure from the covered stent 100, and the envelope 30a is completely opened. The main stent 10 is basically completely adhered to the wall (except that the first bare wave ring 20 at the proximal end is hooked by the post-release structure). In addition, since the diameter-reducing guide wire 741 or the suture structure is completely released and withdrawn, the hooking and fixing between the loop wire of the branch sheath 77 and the main stent 10 of the envelope 30a are released, and the branch guide wire 773 can be easily withdrawn. At this time, the branch stent 50 is completely unfolded and fitted to the branch blood vessel, as Fig.39 shown.

[0156] The present invention also provides another stent system 700, as Fig.40 shown. The stent system 700 includes the above-mentioned covered stent 100, delivery device 70 and pre-set catheter 79. The delivery device 70 includes the above-mentioned sheath-core assembly 71, support rod 72, sheath 73, diameter-reducing releasable member 74 and handle assembly 75, that is, the stent system 700 does not include the above-mentioned branch sheath 77, and other structures are included. In addition, as Figures 41-43As shown, the stent system 700 further includes a pre-set catheter 79. The pre-set catheter 79 extends along the cavity of the main stent 10, and the pre-set catheter 79 and the main stent 10 are axially relatively movable. The distal end of the pre-set catheter 79 can penetrate out of the branch stent 50. The setting of the pre-set catheter can directly select the pre-set catheter into the branch blood vessel, without the need to puncture or incise the blood vessel at the other end of the branch blood vessel to capture the branch guide wire, reducing the pain of the patient. At the same time, it can avoid the problem that the guide wire is easily entangled with the super-stiff guide wire of the main stent during the capture process, reducing the surgical difficulty of the doctor during the branch selection process and reducing the operation time.

[0157] The covered stent includes a semi-restraint structure. The semi-restraint structure includes a wrapping member, and the wrapping member can be set as an envelope or a binding wire. Both the envelope and the binding wire can be used to radially restrain the main stent. When the pre-set catheter is set, in addition to the semi-restraint being achieved by using the envelope and the diameter-restraining releasable member, the semi-restraint can also be achieved by correspondingly arranging the binding wires along the circumferential wave loops at intervals and cooperating with the diameter-restraining guide wire. Among them, if the natural straightening length W0 of the binding wire and the circumference C of the covered stent 100 at the corresponding position of the binding wire in the natural expansion state satisfy: W0 ≤ C / 4.

[0158] Combined Figures 41-43 As shown, the pre-set catheter 79 includes a straight tube section 791 and a pre-bent section 792. The pre-bent section 792 is arranged on the distal side of the straight tube section 791. The connection between the straight tube section 791 and the pre-bent section 792 forms a bending point. The angle range of the pre-bending angle γ of the pre-bent section 792 relative to the straight tube section 791 satisfies: 0° < γ ≤ 60°; where the pre-bending angle γ is the angle between the straight line where the straight tube section 791 is located and the tangent line at the distal end point T of the center of the large bend side of the pre-set catheter 79. A visualization member 793 is provided at the distal end of the pre-set catheter 79 to display the position of the distal end of the pre-set catheter 79, facilitating the insertion of the distal end of the pre-set catheter 79 into the branch blood vessel. The proximal end of the pre-set catheter 79 extends out of the proximal end of the handle assembly 75 and has a margin, facilitating the adjustment of the pre-set catheter 79 to select the branch blood vessel and also facilitating the insertion of the guide wire through the pre-set catheter 79 directly into the branch blood vessel.

[0159] The support rod 72 further includes a third channel 723 for the pre-set catheter 79 to axially pass through, as Fig.26a shown.

[0160] As Fig.42As shown, one side of the proximal end of the main body stent 10 includes a gap 15. At least a part of the pre-bent section 792 of the pre-set catheter 79 extends beyond one side of the proximal end of the main body stent 10. In this embodiment, the first bare wave ring 20 is hooked on the post-release structure of the delivery device 70, and the gap 15 is formed due to radial compression between the wave rods of the first bare wave ring 20 hooked on the post-release structure; in the delivery state, at least a part of the pre-bent section 792 is embedded in the gap 15 to maintain the pre-bent shape of the pre-bent section. When the part of the pre-set catheter 79 exposed outside the covered stent is retracted into the sheath 73, it prevents the pre-bent shape of the pre-set catheter 79 from being straightened due to the extrusion between the covered stent 100 and the sheath 73.

[0161] Another stent system 700 is used for the surgical method of aortic arch implantation, which can be combined with Figure 40-43 The delivery device is briefly summarized as follows:

[0162] As Fig.44 shown, it is introduced into the ascending aorta by using a super-stiff guide wire 82 to establish an access channel for the aortic arch, and then the stent system 700 is introduced along the super-stiff guide wire 82. The stent system 700 is slowly introduced into the human body along the super-stiff guide wire 82 until the distal end of the stent system 700 is introduced to the descending aorta position, as Fig.45 shown.

[0163] By retracting the sliding handle 752 to retract the sheath 73 to the distal end of the main body stent 10, the main body stent 10 bundled by the envelope 30a is exposed outside the sheath 73 in the state of being wrapped by the envelope 30a. Since the covered stent 100 is radially bundled by the envelope 30a, after the sheath 73 is retracted, the stent system 700 can still be adjusted along the super-stiff guide wire 82, so as to accurately position the covered stent 100. The branch stent 50 and the pre-set catheter 79 are exposed after the sheath 73 is retracted, as Fig.46 shown;

[0164] Rotate the proximal end of the pre-set catheter 79 to disengage the pre-bent section 792 of the pre-set catheter 79 from the gap 15 of the first bare wave ring 20, and then push the pre-set catheter 79 to select the pre-set catheter 79 into the branch vessel (shown as the left subclavian artery), and introduce a branch guide wire 83 along the pre-set catheter 79 into the branch vessel, as Figures 47-48 shown;

[0165] As Fig.49 shown, push the stent system 700 forward until the annular support 13 is facing the left subclavian artery, and then retract the diameter-reducing guide wire 741, so that after the envelope 30a is opened, the covered stent 100 naturally expands to be basically wall-adhering, as Fig.50 shown;

[0166] As Fig.51As shown, the first bare wave coil 20 is released, the pre-placed catheter 79 and the conveyor 70 are withdrawn, an externally connected extension stent 90 is implanted along the branch guide wire 83, and the branch guide wire 83 is withdrawn, as shown in FIG. Fig.52 shown.

[0167] The stent system 700 provided in this embodiment, due to the provision of the pre-placed catheter 79, makes it easier for the pre-placed catheter 79 to select the branch blood vessel, thereby facilitating the branch guidewire 83 to be selected into the branch blood vessel to establish a branch pathway, which can avoid the problem of the guidewire being difficult to select the branch blood vessel, and also avoids the problem of guidewire entanglement without the need to cut the upper limb access, thereby greatly reducing the operation time; and, the pre-bent section 792 of the pre-placed catheter 79 can adapt to different anatomical forms, and is also suitable for anatomical forms with a large branch angle that is difficult to select. After the pre-placed catheter 79 is selected into the branch blood vessel, the difficulty of selecting the branch guidewire 83 into the branch blood vessel can be reduced, thereby reducing the operation time.

[0168] Due to the coordinated arrangement of the capsule 30a and the pre-placed catheter 79, when the coated stent 100 is wrapped in the capsule 30a, a narrow and relatively uniform channel in the axial direction is formed in the contracted coated stent 100 for the pre-placed catheter 79 to pass through. Since there is no need for the sheath 73 outside the channel to radially constrain the coated stent 100, the friction force of the sheath 73 on the pre-placed catheter 79 can be reduced, making the delivery of the pre-placed catheter 79 smoother.

[0169] At the same time, the relationship between the width W of the envelope 30a and the circumference C of the lumen of the coated stent 100 at its corresponding position satisfies: W≤C / 4; so that the compression radius of the coated stent in the semi-constrained state is small, that is, the radial compression degree of the coated stent is maintained at a large degree; on the one hand, it can ensure that the channel size is slightly larger than the outer diameter of the preset catheter 79, so that the delivery of the preset catheter 79 is smooth, even if the wave coils of the radially compressed coated stent are stacked crowded, the preset catheter is preset in the coated stent, and due to the soft wrapping of the envelope, a radial soft buffer can be provided, reducing the friction between the preset catheter and the stacked main wave coils, and when delivery is required along the axial direction, the smoothness of delivery can still be guaranteed; on the other hand, On the one hand, it can ensure that the channel size is not too large, and there is a certain restriction on the radial space of the pre-set catheter 79, which can avoid the pre-set catheter 79 from bending in the channel during the delivery process; in addition, the radial compression of the coated stent 100 by the coating 30a is relative to the compression of the coated stent 100 by the sheath 73, and the friction force on the pre-set catheter 79 is smaller, and because the coating 30a wraps the main stent 10 uniformly in the axial direction of the main stent 10, it can also avoid the situation where, when the coated stent 100 is bundled with wires, some positions that are not tied by wires are lifted up due to the self-expansion force of the main wave coil 11, resulting in a larger channel, and the pre-set catheter 79 is bent at a position with a larger channel space.

[0170] It can be understood that, in order to achieve a greater degree of radial compression of the envelope, the relationship between the width W of the envelope 30a and the lumen circumference C of the covered stent 100 at its corresponding position can also be set to satisfy: W ≤ C / 5; even after the envelope wraps the covered stent, the channel space after the radial compression of the covered stent is small. Since the envelope is a flexible film, its radial compression of the covered stent is a soft wrapping. When the pre-set catheter is axially pre-set in this space, the pre-set catheter can smoothly slide axially along the narrow space. At the same time, the envelope radially squeezes the covered stent, which can avoid the situation where the pre-set catheter bends in the channel space.

[0171] It can be understood that, in one of the embodiments, the stent system 700 may further include a pre-set guide wire. The pre-set guide wire is disposed within the pre-set catheter 79 and extends along the axial channel of the pre-set catheter 79; the distal end of the pre-set guide wire extends beyond the bending point of the pre-bent section 792 and the straight section 791, preventing the pre-bent section 792 from being embedded in the gap 15 and always maintaining the bending of the pre-bent section 792, which may narrow the passage at the bending point, resulting in difficulty for the guide wire to pass through the too-narrow channel at the bending point during subsequent surgical procedures, thereby increasing the surgical difficulty.

[0172] In other embodiments, the covered stent 100 provided by the present invention may further include an embedded stent 60, so that the covered stent can be used in the case where an aneurysm involves the left common carotid artery, such as Figure 53-54 As shown, the covered stent 100 further includes another window. The embedded stent 60 is disposed on the distal side of the branch stent 50. The embedded stent 60 and the branch stent 50 are at least partially on the same axial line, so that when the branch stent is aligned with the left common carotid artery, the window corresponding to the embedded stent 60 can face the left subclavian artery.

[0173] Such as Figure 53-54 The release process of the stent system corresponding to the covered stent provided is as Figure 55-60 shown. The stent system is used for the surgical method of aortic arch implantation and can be combined with Figure 40-43 The delivery device is simply summarized as follows:

[0174] The process of establishing the aortic access is the same as Figure 44-Figure 47The process is the same, that is, using the super-stiff guide wire 82 to introduce it into the ascending aorta to establish an access channel for the aortic arch, and then introducing the stent system along the super-stiff guide wire 82. The stent system is slowly introduced into the human body along the super-stiff guide wire 82 until the distal end of the stent system is introduced to the descending aorta position; by retracting the sliding handle 752, the sheath 73 is retracted to the distal end of the main stent 10, so that the main stent 10 constricted by the encapsulation 30a is exposed outside the sheath 73 in a state wrapped by the encapsulation 30a. Since the covered stent 100 is radially constricted by the encapsulation 30a, after the sheath 73 is retracted, the stent system can still be adjusted along the super-stiff guide wire 82, so as to accurately position the covered stent 100, and the branch stent 50 and the pre-set catheter 79 are exposed after the sheath 73 is retracted.

[0175] Further, rotate the proximal end of the pre-set catheter 79 and slightly retract it to disengage the pre-bent section 792 of the pre-set catheter 79 from the gap 15 of the first bare wave ring 20, and then push the pre-set catheter 79 to select the pre-set catheter 79 into the left common carotid artery, and introduce a branch guide wire 83 along the pre-set catheter 79 into the branch blood vessel, such as Fig.55 shown;

[0176] such as Fig.56 shown, push the stent system forward until the annular support 13 is facing the left common carotid artery, and then retract the diameter-reducing guide wire 741. After the encapsulation 30a is opened, the covered stent 100 naturally expands to be basically attached to the wall, such as Fig.57 shown;

[0177] such as Fig.58 shown, release the first bare wave ring 20, retract the pre-set catheter 79 and the delivery device 70, implant an external extended stent 90 along the branch guide wire 83, and withdraw the branch guide wire 83, such as Fig.59 shown;

[0178] such as Fig.60 shown, implant an external small stent 91 along the embedded stent 60. One end of the small stent 91 overlaps and matches with a part of the embedded stent, so that the small stent 91 extends to the left subclavian artery.

[0179] It can be understood that in other embodiments, the covered stent may further include two embedded stents, so as to be used in the case where the aortic aneurysm involves the three branches of the aortic arch. The surgical process can refer to the above process, and the branch stent corresponds to the brachiocephalic trunk artery, which will not be elaborated here.

[0180] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered to be within the scope described in this specification.

[0181] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. A stent graft, characterized in that: The coated stent includes a main body stent, a capsule and a binding wire, the main body stent includes a main body wave ring and a main body coating, the main body coating is covered on the main body wave ring, the binding wire includes a first binding wire, the capsule and the main body stent are connected to one side of the main body stent through the first binding wire, the coated stent also includes a first positioning member and a second positioning member, the first positioning member is arranged at the proximal end of the main body stent, and the second positioning member is arranged at the proximal end of the capsule, when the coated stent is in a naturally expanded state, when the capsule is naturally attached to the main body stent along the circumferential direction, the first positioning member and the second positioning member are approximately on the same radial line.

2. The stent graft according to claim 1, characterized in that: The stent graft also includes a second binding wire, and the first positioning member is configured as the second binding wire.

3. The stent graft according to claim 1, characterized in that: The second positioning member is configured as a protrusion, and the protrusion protrudes from the proximal end surface of the main body coating; Alternatively, the second positioning member is configured as a developing structure.

4. The stent graft according to claim 1, characterized in that: The main body support includes a binding accessory, the binding accessory includes a part of the main body wave ring or includes a binding line, the binding accessory extends along the main body coating, the main body coating includes a first perforation and a second perforation, the first perforation and the second perforation are respectively arranged on both sides of the extension direction of the binding accessory, and the first binding line passes through the first perforation and the second perforation and crosses the binding accessory.

5. The stent graft according to claim 1, characterized in that: The first binding wire is connected to the wave rod, wave crest or wave trough of the main wave coil; Alternatively, one of the main wave coils is connected by a steel sleeve to form a wavy ring, the first binding wire is connected to the main wave coil, and the first binding wire is close to the edge of the steel sleeve.

6. The stent graft according to claim 1, characterized in that: The main body coating includes a linear film, and the linear film is wound along the circumference of the main body coating; The first binding wire is connected to the wave rod of the main wave coil, and at least one linear film is respectively arranged on the proximal end side and the distal end side of the first binding wire; Or, the first binding wire is connected to the wave crest of the main wave rod, and at least one linear membrane is arranged on the distal end side of the first binding wire; Alternatively, the first binding wire is connected to the trough of the main wave rod, and at least one linear membrane is arranged on the distal end side of the first binding wire.

7. The stent graft according to claim 4, characterized in that: The main body coating includes a linear film, which is wound along the circumference of the main body coating; the shortest distance L1 from the linear film to the first perforated edge in the axial direction satisfies: L1≤3mm, and / or the shortest distance L2 from the linear film to the second perforated edge in the axial direction satisfies: L2≤3mm.

8. The stent graft according to claim 7, characterized in that: The line where the connecting straight line of the geometric center of the first perforation and the geometric center of the second perforation is defined as W1, and the linear membrane includes a first linear membrane, and the first linear membrane is arranged on the proximal end side of the first perforation and the second perforation, and the angle β1 between the first linear membrane and W1 satisfies: 0°≤β1≤20°.

9. The stent graft according to claim 8, characterized in that: The linear film further includes a second linear film, which is disposed at the distal end side of the first through hole and the second through hole, and an angle β2 between the second linear film and W1 satisfies: 0°≤β2≤20°.

10. The stent graft according to claim 7, characterized in that: The envelope includes a buffer, a third perforation and a fourth perforation, the buffer extends along the plane where the envelope is located, the third perforation and the fourth perforation are respectively arranged on both sides of the extension direction of the buffer, the first binding line passes through the first perforation and the second perforation and crosses the binding accessory, and then passes through the third perforation and the fourth perforation and crosses the buffer before being tied.

11. The stent graft according to claim 4, characterized in that: The coated stent also includes a branch stent, and the lumen of the branch stent is connected to the lumen of the main stent. The main stent includes a first side and a second side along the circumferential direction. The capsule is connected to the first side of the main stent, and the branch stent is connected to the second side of the main stent. The main stent includes a proximal end segment, and at least one binding attachment is arranged on the first side of the proximal end segment.

12. The stent graft according to claim 11, characterized in that: The proximal end section includes a first main body wave coil and a second main body wave coil in sequence from the proximal end to the distal end, and the binding wire also includes a second binding wire; The first binding wire is arranged on a wave rod, wave crest or wave trough on a first side of the first main body wave coil, and the second binding wire is arranged on a wave rod, wave crest or wave trough on a first side of the second main body wave coil; Or, the main body support includes a curved section, which is closer to the distal end than the proximal end section, and the curved section includes a third main wave coil and a fourth main wave coil from the proximal end to the distal end in sequence, and the first binding wire is arranged on the wave rod or wave crest or wave trough on the first side of the first or second main wave coil, and the second binding wire is arranged on the wave rod or wave crest or wave trough on the first side of the third or fourth main wave coil.

13. A stent system, comprising the stent graft according to any one of claims 1 to 12, characterized in that: The stent system also includes a conveyor, which includes a sheath core assembly, a support rod, a sheath tube, and a detachable member, the sheath core assembly includes an inner sheath core and an outer sheath core, the inner sheath core, the outer sheath core, the support rod and the sheath tube are sequentially sleeved from the inside to the outside, and the support rod is sleeved on the outside of the sheath core assembly; the conveyor also includes a guide head, which is arranged at the distal end of the inner sheath core, and the distal end of the support rod and the proximal end of the guide head are spaced apart to form a loading space for the coated stent; the detachable member cooperates with the envelope to achieve radial contraction and release of the coated stent; the coated stent is loaded in the loading space, and the first positioning member and the second positioning member are fixed by suturing with a second suture.

14. The support system according to claim 13, characterized in that: The coated stent also includes an embedded stent, which is arranged on one side of the distal end of the branch stent.

15. A method for manufacturing a bracket system, the method being used to manufacture the bracket system according to claim 13, characterized in that: A coated stent is provided, with the fixed connection point of the first binding line between the envelope and the main stent as the boundary, and the main stent includes a first part and a second part; The main stent is sheathed on the sheath core assembly, and then the first part of the main stent is radially compressed and loaded on the first auxiliary sleeve, and the second part of the main stent is radially compressed and loaded on the second auxiliary sleeve, and then the envelope is wrapped on the outer surface of the auxiliary sleeve, and at the same time, the bundle diameter detachable member is axially passed through the envelope to achieve radial compression and wrapping of the main stent by the envelope; The auxiliary sleeve is withdrawn, the first positioning piece is sutured to the second positioning piece, and the sutured coated stent is loaded into the sheath tube of the conveyor to complete the loading of the coated stent into the sheath to form the stent system.

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