Covered stent and stent system

Abstract

The invention provides a covered stent and a stent system.The covered stent comprises a main stent body and a wrapping part, 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, and the wrapping part is connected to one side of the main stent body; the wrapping part wraps the main body stent in a releasable mode so that the main body stent can be compressed or unconstrained in the radial direction, the width of a certain position of the wrapping part is defined as W, and the perimeter of the covered stent at the position corresponding to the width W of the wrapping part is defined as C when the covered stent is in a natural expansion state, the relation between W and C meets the condition that W is smaller than or equal to C / 4. W is less than or equal to C / 4, so that the semi-constraint degree of the covered stent can be ensured, the stent can be repeatedly adjusted in the axial direction when being implanted into a blood vessel, and meanwhile, a channel convenient for selecting a branch blood vessel is provided when the covered stent is radially compressed by a wrapping piece, so that the movable space of the channel in the radial direction is not too large.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to a stent graft and a stent system. Background Art

[0002] In the past decade, aortic stent graft endovascular exclusion has been widely used in lesions such as aneurysms and arterial dissections of the thoracic and abdominal aorta. It has a precise effect, minimal trauma, rapid recovery, and few complications, and has become a first-line treatment method.

[0003] For specific lesions involving aortic aneurysms or dissections that extend into branches, such as the aortic arch, celiac trunk, bilateral renal arteries, or superior mesenteric arteries, the use of a covered stent can compromise the blood supply to these branches. To address this, appropriate holes are created in the covered stent to perfuse the branches. Typically, the diameter of the holes approximates that of the branches. Ensuring that the holes coincide with the branches and guiding the guidewire into the branches is crucial for branch reconstruction. A common approach for this is to circumferentially constrain the stent with binding wire, causing radial compression. After release from the delivery sheath, the stent is in a radially compressed state, facilitating intraoperative alignment and enabling precise positioning. Alternatively, for locations where aortic aneurysms or dissections do not extend into branches but require specific stent positioning, this semi-constrained approach can be used to further precisely position the stent before full release. However, the currently used binding wire cannot completely wrap the axial direction of the stent, which may cause the following problems: the stent is partially covered by the binding wire, and the metal wire on the stent has a strong self-expansion force, causing it to partially warp, 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, causing the blood clot attached to the blood vessel wall to fall off and flow into the branch vessels. Summary of the Invention

[0004] At least one technical problem solved by the present invention is how to ensure the uniformity of the semi-constraint of the coated stent in the axial direction, thereby facilitating repeated axial adjustment of the stent position, while ensuring that when the coated stent is radially compressed by the wrapping member, a channel is provided for selecting branch blood vessels.

[0005] The present invention provides a coated stent, which includes a main body stent and a wrapping piece. The main body stent includes a main body wave ring and a main body coating. The main body coating covers the main body wave ring. The wrapping piece is connected to one side of the main body stent. The wrapping piece can releasably wrap the main body stent so that the main body stent is radially compressed or released. The width of the wrapping piece at a certain position is defined as W, and the circumference of the coated stent at a position corresponding to the width W of the wrapping piece in a naturally expanded state is defined as C. Then the relationship between W and C satisfies: W≤C / 4.

[0006] In one embodiment, the wrapping piece is connected to the main body support by a binding wire, the main body support includes a binding accessory, the binding accessory includes a part of the main body wave ring or includes a binding wire, the binding accessory extends along the main body covering, the main body covering 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 binding wire passes through the first perforation and the second perforation and crosses the binding accessory.

[0007] In one embodiment, the binding wire is connected to the wave rod, wave crest or wave trough of the main wave coil;

[0008] Alternatively, one of the main wave coils is connected by a steel sleeve to form a wave-shaped ring, and the binding wire is connected to the main wave coil, and the binding wire is close to the edge of the steel sleeve.

[0009] In one embodiment, the main body covering film includes a linear film, and the linear film is wound along the circumference of the main body covering film;

[0010] The binding wire is connected to the wave rod of the main wave coil, and at least one linear film is respectively provided on the proximal end side and the distal end side of the binding wire;

[0011] Alternatively, the binding wire is connected to the crest of the main wave rod, and at least one linear membrane is provided on the distal end side of the binding wire;

[0012] Alternatively, the binding wire is connected to the trough of the main wave rod, and at least one linear membrane is provided on the distal end side of the binding wire.

[0013] In one embodiment, the main body coating includes a linear film, which is wound along the circumference of the main body coating; the shortest distance L1 of the linear film to the first perforated edge in the axial direction satisfies: L1≤3mm, and / or the shortest distance L2 of the linear film to the second perforated edge in the axial direction satisfies: L2≤3mm.

[0014] In one embodiment, the wrapping piece includes a buffer piece, a third perforation and a fourth perforation, the buffer piece extends along the plane where the wrapping piece is located, the third perforation and the fourth perforation are respectively arranged on both sides of the extension direction of the buffer piece, the 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 piece and is tied.

[0015] In one embodiment, 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 wrapping piece is connected to the first side of the main stent by a binding wire, 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 provided on the first side of the proximal end segment.

[0016] In one embodiment, 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 includes a first binding wire and a second binding wire;

[0017] 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;

[0018] 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.

[0019] The present invention also provides a stent system, which includes the coated stent as described above, and the stent system also includes a conveyor, the conveyor including a sheath core assembly, a support rod, a sheath tube, and a detachable bundle diameter piece, the sheath core assembly including 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 connected from the inside to the outside, and the support rod is connected to the outside of the sheath core assembly; the conveyor also includes a guide head, the guide head 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 bundle diameter piece cooperates with the wrapping piece to realize radial contraction and release of the coated stent.

[0020] In one embodiment, the stent system further includes a pre-placed catheter, which extends along the lumen of the main stent, and the distal end of the pre-placed catheter can pass through the branch stent.

[0021] In one embodiment, the pre-placed catheter includes a straight tube section and a pre-bent section, and the pre-bent section is arranged on the distal side of the straight tube section.

[0022] In one embodiment, at least part of the pre-bent section of the pre-placed catheter extends beyond the proximal end of the main stent, and the proximal end of the main stent includes a gap. In the delivery state, at least part of the pre-bent section is embedded in the gap to maintain the pre-bent shape of the pre-bent section.

[0023] A technical effect of an embodiment of the present invention is: setting the relationship between W and C to satisfy: W≤C / 4 can ensure the semi-constraint degree of the coated stent, facilitate repeated axial adjustment of the stent when implanted in the blood vessel, and at the same time ensure that when the coated stent is radially compressed by the wrapping, it provides a channel for selecting branch blood vessels, so that the radial movable space of the channel is not too large. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic structural diagram of a stent graft provided in one embodiment of the present invention;

[0025] Figure 2 A schematic diagram of a partial structure of a stent graft provided in one embodiment of the present invention (part of the main body graft is omitted);

[0026] Figure 3 This is a partial structural diagram of the stent graft (part of the main body graft is omitted) and the binding wire provided in one embodiment of the present invention;

[0027] Figure 4 A planar expansion diagram of the envelope provided in one embodiment of the present invention;

[0028] Figure 5 A schematic structural diagram of a stent graft provided in another embodiment of the present invention;

[0029] Figure 6 This is a schematic diagram of the structure of the connection between the envelope and the main stent provided in one embodiment of the present invention (the main stent covering is omitted);

[0030] Figure 7 A schematic structural diagram of a portion of a main body support provided in one embodiment of the present invention;

[0031] Figure 7a A schematic structural diagram of a portion of a main body support provided in another embodiment of the present invention;

[0032] Figure 7b A schematic structural diagram of a portion of a main body support provided in another embodiment of the present invention;

[0033] Figure 8 for Figure 7 Enlarged view of point B in the middle;

[0034] Figure 9 A schematic structural diagram of a stent graft provided in another embodiment of the present invention;

[0035] Figure 10 For Figure 9 bent state diagram for use in a curved blood vessel;

[0036] Figure 11 Structure diagram of a covered stent according to another embodiment of the present application;

[0037] Figure 12 For Figure 11 bent state diagram for use in a curved blood vessel;

[0038] Figure 13 For Figure 11 right view;

[0039] Figure 14 For Figure 11 structure diagram of a covered stent (showing a branch stent portion within a main stent)

[0040] Figure 14a Figure 14 enlarged view of the portion C in FIG. 10;

[0041] Figure 15 Structure diagram of a stent system according to an embodiment of the present application;

[0042] Figure 16 Structure diagram of a support rod according to an embodiment of the present application, viewed in an axial direction;

[0043] Figure 16a Structure diagram of a support rod according to another embodiment of the present application, viewed in an axial direction;

[0044] Figure 17 Structure diagram of a covered stent of a stent system according to an embodiment of the present application, being radially compressed by a sheath (the bundle diameter releasable member includes a bundle diameter guide wire);

[0045] Figure 18 Structure diagram of a covered stent of a stent system according to another embodiment of the present application, being radially compressed by a sheath (the bundle diameter releasable member includes a releasable suture structure);

[0046] Figure 19 For Figure 18 structure diagram of a portion of the constraining section in which the constraint is partially released;

[0047] Figure 20 Structure diagram of a portion of a guide head and inner sheath core according to an embodiment of the present application;

[0048] Figure 21 Structure diagram of a catch member in a rear release structure according to an embodiment of the present application;

[0049] Figure 22 A diagram showing a closable state formed by the engagement of a latch and a latch slot of a rear release structure provided by one embodiment of the present invention;

[0050] Figure 23 A guide catheter passage through a branch vessel established when the stent system provided by one embodiment of the present invention is implanted in the aortic arch;

[0051] Figure 24 This is a schematic diagram of a stent system provided by one embodiment of the present invention being introduced into the aortic arch along a super-hard guidewire;

[0052] Figure 25 This is a schematic diagram of the initial positioning of the stent system provided by one embodiment of the present invention at the aortic arch after the sheath is withdrawn;

[0053] Figure 26 A schematic diagram showing a branch port of a covered stent of a stent system provided by one embodiment of the present invention aligned with a branch blood vessel;

[0054] Figures 27 and 28 FIG. 1 is a diagram showing a stent system provided in one embodiment of the present invention, wherein the guide wire or the lead segment of the suture structure is pulled backward so that the main stent is sequentially deployed from the proximal end to the distal end and adheres to the wall.

[0055] Figure 29 For relative Figure 28 Schematic diagram of withdrawing the branch sheath to allow the branch stent to expand and fit the branch vessel;

[0056] Figure 30 A schematic structural diagram of a support system provided in another embodiment of the present invention;

[0057] Figure 31 for Figure 30 Schematic diagram of the structure of the covered stent of the stent system;

[0058] Figure 32 for Figure 31 Enlarged view of point D in the middle;

[0059] Figure 33 A schematic structural diagram of a pre-placed catheter in a stent system provided in another embodiment of the present invention;

[0060] Figure 34 This is a schematic diagram of a super-stiff guidewire being introduced into the aortic arch before implantation of a stent system provided in another embodiment of the present invention;

[0061] Figure 35 This is a schematic diagram of a stent system provided by another embodiment of the present invention being introduced into the aortic arch along a super-hard guidewire;

[0062] Figure 36 For relative Figure 35 Schematic diagram of withdrawing the sheath so that the stent graft, which is contracted by the envelope, is exposed outside the sheath in a state of being wrapped in the envelope;

[0063] Figure 37 For relative Figure 36 Schematic diagram of rotating the pre-set catheter to separate the pre-bent section of the pre-set catheter from the gap of the first bare wave ring;

[0064] Figure 38 For relative Figure 37 Schematic diagram of pushing the pre-placed catheter and directly inserting the pre-placed catheter into the branch vessel;

[0065] Figure 39 For relative Figure 38 Schematic diagram of pushing the stent system forward until the annular support member faces the left subclavian artery;

[0066] Figure 40 For relative Figure 39 Schematic diagram of withdrawing the guidewire to open the capsule and allowing the stent graft to naturally expand until it is almost adherent to the wall;

[0067] Figure 41 For relative Figure 40 Schematic diagram of using the rear release structure to release the first bare wave coil and withdraw the pre-placed catheter and conveyor;

[0068] Figure 42 For relative Figure 41 Schematic diagram of implanting an external extension stent along the branch guidewire and withdrawing the branch guidewire;

[0069] Figure 43 A schematic structural diagram of a stent graft provided in another embodiment of the present invention;

[0070] Figure 44 for Figure 43 Right view;

[0071] Figure 45 for Figure 43 Schematic diagram of the stent graft being introduced into the aortic arch along a super-stiff guidewire by the stent system, the sheath being withdrawn to expose the capsule outside the sheath, and the pre-placed catheter being inserted into the left common carotid artery;

[0072] Figure 46 For relative Figure 45 Schematic diagram of pushing the stent system forward until the annular support member faces the left common carotid artery;

[0073] Figure 47 For relative Figure 46 Schematic diagram of withdrawing the guidewire to open the capsule and allowing the stent graft to naturally expand until it is almost adherent to the wall;

[0074] Figure 48For relative Figure 47 Schematic diagram of using the rear release structure to release the first bare wave coil and withdraw the pre-placed catheter and conveyor;

[0075] Figure 49 For relative Figure 48 Schematic diagram of implanting an externally connected extended stent into the left common carotid artery along the branch guidewire and withdrawing the branch guidewire;

[0076] Figure 50 For relative Figure 49 A small external stent was implanted into the left subclavian artery to match the internal stent. DETAILED DESCRIPTION

[0077] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0078] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "inner," "outer," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0079] "Axial" generally refers to the length direction of the medical device when it is being transported, and "radial" generally refers to the direction of the medical device perpendicular to its "axial" direction. The "axial" and "radial" of any component of the medical device are defined based on this principle. In addition, when explaining the luminal stent or the covered stent, the orientation can be defined according to the direction of blood flow in the blood vessel. In the present invention, the blood flow is defined as flowing from the proximal end to the distal end of the stent. In the field of interventional medical devices, for a conveyor that transports the medical device when it is implanted in the human body or animal body, the end closer to the operator is defined as the "proximal end" and the end farther from the operator is defined as the "distal end". The "proximal end" and "distal end" of any component of the conveyor are defined based on this principle.

[0080] The "corrugated ring" in the present invention is a closed annular structure, also known as a corrugated ring, braided or cut from a metal elastic material. A single main corrugated ring can be connected to the corrugated metal elastic material at both ends by a steel sleeve, thereby forming a ring-shaped main corrugated ring. The metal elastic material includes known materials used in implantable medical devices or combinations of various biocompatible materials, such as alloys of two or more single metals selected from cobalt, chromium, nickel, titanium, magnesium, and iron, as well as 316L stainless steel, nickel-titanium-tantalum alloy, or other biocompatible metal elastic materials. The corrugated ring has the ability to expand radially and contract radially under external force. Upon removal of the external force, it self-expands and returns to its original shape and maintains its initial shape. Thus, after implantation into a lumen, it can adhere closely to the inner wall of the lumen through its radial support force. The corrugated ring's waveform is not limited and includes Z-shaped, M-shaped, V-shaped, and sinusoidal waves. The corrugated ring includes multiple crests (also known as proximal vertices), multiple troughs (also known as distal vertices), and a wave bar connecting adjacent crests and troughs. Among them, a vertex (proximal vertex or distal vertex) and two wave rods connected to the vertex form a single wave.

[0081] The present invention provides a stent graft 100, such as Figure 1 As shown, the coated stent 100 includes a main stent 10, a first bare wave coil 20 and a wrapping member 30, the main stent 10 includes a main wave coil 11 and a main coating 12, and the main coating 12 covers the main wave coil 11; the main wave coil 11 is a ring structure formed by multiple waveform units connected end to end, wherein the waveform unit refers to a single wave structure composed of a crest, a wave rod and a trough, and the shape of the waveform unit is not limited; each main wave coil 11 can be a regular ring structure formed by multiple waveform units of the same height, or an irregular ring structure including high and low waves formed by waveform units of different wave heights; adjacent main wave coils 11 can all be regular ring structures, or they can all be irregular ring structures including high and low waves, or they can be a combination of regular ring structures and irregular ring structures including high and low waves, which is not limited here.

[0082] The main body coating 12 is a tubular structure with openings at both ends. Multiple main body coils 11 are arranged axially and connected through the tubular main body coating 12, thereby forming a tubular main body bracket 10; the distal end of the first bare coil 20 is connected to the proximal end of the main body bracket 10, and the first bare coil 20 is at least partially exposed outside the main body coating 12.

[0083] The wrapping member 30 is connected to one side of the main support 10 or is arranged around the main support. The wrapping member can releasably wrap the main support 10 so that the main support 10 is radially compressed or unconstrained, thereby constraining the compressed main support 10 within the wrapping member or allowing the main support 10 to be unwrapped and expand naturally. In one embodiment, the wrapping member 30 can be set as a membrane 30a. In some embodiments described below, the wrapping member is described using a membrane as an example.

[0084] like Figure 2-3 As shown, the main body coating 12 includes a first film layer 121 and a linear film 122. The linear film 122 is wound along the circumference of the main body coating 12. The linear film 122 can be multiple lines wound along the circumference of the coated stent 100 parallel to the radial direction, or it can be one line or multiple lines spirally wound along the circumference of the coated stent 100; wherein, the first film layer 121 is attached to one side of the main body wave ring 11, and the linear film 122 can be arranged between the first film layer 121 and the main body wave ring 11, can be arranged on the side of the first film layer 121 away from the main body wave ring 11, or can be arranged on the side of the main body wave ring 11 away from the first film layer 121, which is not limited here; in one embodiment, the linear film 122 is arranged on the side of the main body wave ring 11 away from the first film layer 121, and can cooperate with the first film layer 121, thereby having a restraining effect on the main body wave ring 11.

[0085] In one embodiment, the main body coating 12 further includes a second film layer 123, which is attached to a side of the main body wave coil 11 away from the first film layer 121. The first film layer 121 is attached to the inner side of the main body wave coil 11, and the second film layer 123 is attached to the outer side of the main body wave coil 11. The linear film 122 is disposed between the main body wave coil 11 and the second film layer 123, and the linear film 122 is spirally wound upward along the circumference of the coated stent 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 be fixed together by gluing or hot pressing.

[0086] The linear film 122 can be a linear structure formed by a single wire or multiple wires, and the average linear diameter of the linear structure ranges from 0.05 mm to 0.3 mm. The cross-sectional area of the linear structure can be circular, elliptical, rectangular, etc., and the thickness of the linear structure in the extending direction can be uniform or non-uniform, which is not limited herein. When the cross-sectional area of the linear structure is non-circular, the thickness of the linear structure in the radial direction of the stent-graft 100 ranges from 0.05 mm to 0.3 mm. The linear film 122 can be made of a biocompatible polymer material such as PTFE wire. In one embodiment, the linear film 122 is spirally wound along the circumferential direction of the stent-graft 100, and the angle of the spiral rising ranges from 0° to 45°. For example, when the linear film 122 is spirally wound along the circumferential direction of the stent-graft 100, the angle of the spiral rising can be 0°, 5°, 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, etc. The linear film 122 can be spirally rising at equal intervals or non-equal intervals, and the linear film 122 can also be spirally spaced at equal intervals or non-equal intervals, which is not limited herein, as long as the linear film 122 passes around each wave.

[0087] As shown in Figure 1 The main stent 10 includes opposite first and second sides 10a and 10b in the circumferential direction, and each of the first and second sides 10a and 10b occupies an arc of 180° in the circumferential direction.

[0088] In combination with Figure 4As shown, the envelope 30a is connected to the first side 10a of the main stent 10, and the envelope 30a is connected to the main stent 10 by a binding wire 40. In one embodiment, the portion of the envelope 30a near the proximal end is connected to the position of the main stent 10 near the proximal end by a binding wire; in this embodiment, the axial length of the envelope 30a is equal to the axial length of the main covering 12. In other embodiments, the axial length of the envelope 30a can also be approximately equal to the axial length of the main covering 12, wherein "approximately equal" here means that the axial length of the envelope 30a is equal to the axial length of the main covering 12. The axial length difference ratio is less than or equal to 10%, so that the proximal end of the envelope 30a extends at least to the center position of the main body wave coil 11 at the nearest end, the distal end of the envelope 30a extends at least to the axial center of the main body wave coil 11 at the farthest end, and the two ends of the envelope 30a do not extend too much beyond the two ends of the main stent 10; the larger of the axial length of the envelope 30a and the axial length of the main body coating 12 is defined as H1, and the smaller of the axial length of the axial length of the envelope 30a and the axial length of the main body coating 12 is defined as H2, then the axial length difference ratio of the two is: (H1-H2) / H2. In one embodiment, the envelope is rectangular, the main body coating is a tubular membrane, and the axial length of the envelope is slightly larger than the axial length of the main body coating, then the axial length of the envelope is H1, and the axial length of the main body coating is H2, such as Figure 4-5 As shown. Define the width of the envelope 30a at a certain position (the direction of the width is perpendicular to the axial direction of the coated stent 100) as W, and define the circumference of the coated stent 100 at a position corresponding to the width of the envelope 30a at a certain position when in the naturally expanded 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 coated stent 100, the radial space in which the pre-placed catheter 79 can move is not too large when the pre-placed catheter 79 is limited to move axially within the compressed coated stent 100.

[0089] The envelope 30a is in the form of an elongated strip. In one embodiment, the envelope 30a is in the form of a rectangular sheet, the length of which corresponds to the axial direction of the main stent 10. At least one limiting hole 31 is provided at each of the two long sides of the envelope 30a near the edge. When multiple main wave rings 11 are provided along the axial direction, multiple limiting holes 31 are provided at intervals along the axial direction at each of the two long sides of the envelope 30a near the edge, so that the guide wire 741 can pass through the limiting holes 31 on the two long sides of the envelope 30a in sequence, so that the envelope 30a is enclosed into a tubular body, thereby wrapping the radially compressed coated stent 100. In this embodiment, a limiting member 35 is provided between the limiting hole 31 and the edge of the envelope 30a to prevent the membrane hole from expanding to the edge of the envelope 30a and breaking the closed state of the membrane hole, thereby preventing the guide wire 741 from passing through the membrane hole and reducing the reliability of the envelope 30a enclosing the tubular body.

[0090] like Figure 1 、 Figure 5 、 Figure 9 and Figure 11 As shown, the envelope 30a is connected to the first side 10a of the main support 10 by a knotted wire 40. When the coated support 100 is loaded or released, the envelope 30a may be subjected to friction, causing relative movement between it and the main coating 12, so that the envelope 30a and the main coating 12 are pulled and subjected to force by the binding wire 40, which may cause the membrane holes on the main coating 12 through which the binding wire 40 passes and the membrane holes on the envelope 30a to expand.

[0091] The envelope 30a also includes a buffer member 32, which is positioned in the middle region of the envelope 30a and extends along the plane of the envelope 30a. In one embodiment, the buffer member 32 can be configured as an axially extending reinforcement wire, with the binding wire 40 passing through the membrane pores of the envelope 30a and across the buffer member 32. In other embodiments, the buffer member 32 can also be configured as a transversely or diagonally extending reinforcement wire. The buffer member 32 can be formed within the plane of the envelope 30a or on the surface of the envelope 30a through a heat treatment together with the envelope 30a. The envelope 30a can be made of PTFE or PET film, and the reinforcement wire can be made of a biocompatible polymer such as PTFE wire. PTFE wire or membrane has good thermal properties, is chemically inert, self-lubricating, and non-sticky, is not easily wetted by tissue fluids, is corrosion-resistant, has the best aging life among plastics, is non-toxic, can withstand pressure, is implantable, and can withstand certain tension and strain. PET film also has excellent physical and chemical properties and can be used as a envelope material.

[0092] The main body bracket 10 includes a binding attachment 111, which extends along the main body coating 12. The main body coating 12 includes a first perforation 124 and a second perforation 125. The first perforation 124 and the second perforation 125 respectively pass through the inside and outside of the main body coating 12, and the first perforation 124 and the second perforation 125 are respectively arranged on both sides of the extension direction of the binding attachment 111. The binding attachment 111 can be set as a wave rod of a main body wave coil 11, that is, the binding attachment 111 includes a part of a main body wave coil; the binding attachment 111 can also be a binding line set on the main body coating 12, and the binding line can be fixed to the main body coating 12 by gluing or hot pressing. In one embodiment, the binding accessory 111 is arranged at the proximal end of the main support 10, and the main support 10 includes a main wave coil 11 arranged at the proximal end, and the binding wire 40 is connected to the wave rod or wave crest or wave trough of the main wave coil 11, that is, the binding accessory 111 is set as the wave rod or wave crest or wave trough of the main wave coil 11; the main wave coil 11 is a wavy ring formed by a metal wire rod extending in a wave-like manner along the circumference of the main support 10, and the first through-hole 124 and the second through-hole 125 are respectively arranged on both sides of the extension direction of the binding accessory 111.

[0093] The envelope 30a includes a third perforation 33 and a fourth perforation 34, which are respectively arranged on both sides of the extension direction of the buffer 32. In one embodiment, the binding wire 40 can pass through the first perforation 124 and the second perforation 125 and cross the binding accessory 111, and then pass through the third perforation 33 and the fourth perforation 34 and cross the buffer 32 before being tied. For the main body coating, the binding wire 40 passes through the binding attachment 111 when passing through the main body coating 12. When the coating bracket 100 is loaded or released, the envelope 30a and the main body coating 12 are pulled by the binding wire 40, and the binding wire 40 mainly pulls the binding attachment 111. When the binding wire 40 is under stress, the possibility of expansion of the membrane holes of the first perforation 124 and the second perforation 125 can be reduced, thereby preventing internal leakage; and the setting of the buffer component 32 can make the binding wire 40 mainly pull the buffer component 32 when it is under stress. When the binding wire 40 is under stress, the possibility of expansion of the membrane holes (the third perforation 33 and the fourth perforation 34) on the envelope 30a can be reduced.

[0094] In other embodiments, the binding wire 40 passes through the first through-hole 124 and the second through-hole 125 and crosses the binding attachment 111 before being tied, and then passes through the third through-hole 33 and the fourth through-hole 34 and crosses the buffer 32 before being tied; for the main body coating, on the one hand, when the binding wire 40 passes through the main body coating 12, it crosses the binding attachment 111. When the coated stent 100 is loaded or released, the envelope 30a and the main body coating 12 are pulled by the binding wire 40. The binding wire 40 mainly pulls the binding attachment 111. When the binding wire 40 is pulled, the binding wire 40 mainly pulls the binding attachment 111. When the wire 40 is subjected to force, the possibility of the membrane holes at the first through-hole 124 and the second through-hole 125 expanding can be reduced, thereby preventing internal leakage. On the other hand, the binding wire 40 passes through the first through-hole 124 and the second through-hole 125 and crosses the binding attachment 111 before being tied to form a breakpoint in force transmission. This can reduce the pulling force on the main body membrane when the envelope is pulled by the binding wire, and has a certain limiting effect on the binding wire crossing the main body membrane, thereby further reducing the possibility of the membrane holes at the first through-hole 124 and the second through-hole 125 expanding. In addition, the provision of the buffer 32 can ensure that when the binding wire 40 is subjected to force, the buffer 32 is mainly pulled. When the binding wire 40 is subjected to force, the possibility of the membrane holes on the envelope 30a (at the third through-hole 33 and the fourth through-hole 34) expanding can be reduced.

[0095] One or more than one fixing connection point can be arranged between the envelope 30a and the main support 10, and the fixing connection point is connected to the position corresponding to the binding accessory 111. In one embodiment, one fixing connection point is arranged between the envelope 30a and the main support 10, the binding wire 40 includes a first binding wire 41, the first binding wire 41 passes through the first perforation 124 and the second perforation 125 on the main envelope 12 and crosses a binding accessory 111, and two wire ends of the first binding wire 41 are located outside the main support 10. At this time, the first binding wire 41 can be knotted at one or two wire knots outside the main support 10, and the wire knot is finally formed between the envelope 30a and the main support 10. Then, the first binding 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 support 10 to prevent the binding wire 40 from loosening, and the knot of the binding wire 40 is formed outside the lumen of the envelope support 100, avoiding affecting the blood flow in the lumen. In other embodiments, as shown in Figure 5 , two fixing connection points can be arranged between the envelope 30a and the main support 10, and the binding wire 40 further includes a second binding wire 42, which can be fixedly connected to the perforations at the corresponding positions on the envelope 30a and the envelope support 100 in the same way as the first binding wire 41, and details are not described herein.

[0096] In one embodiment, as shown in Figure 6-8 , the first binding wire 41 is connected to the wave rod of the main wave coil 11, and at least one wire-shaped film 122 is arranged on the proximal end side and the distal end side of the first binding wire 41 to limit the first perforation 124 and the second perforation 125 from expanding towards the proximal end side and the distal end side. The shortest distance L1 of a wire-shaped film 122 to the edge of the first perforation 124 in the axial direction satisfies: L1≤3mm, and the shortest distance L2 of a wire-shaped film 122 to the edge of the second perforation 125 in the axial direction satisfies: L2≤3mm. In other embodiments, the first binding wire 41 can be connected to the wave crest of the main wave coil 11, and at least one wire-shaped film 122 is arranged on the distal end side of the first binding wire 41 to limit the perforation passing through the main envelope 12 on the inside of the wave crest bending to expand. The first binding wire 41 can also be connected to the wave trough of the main wave coil 11, and at least one wire-shaped film 122 is arranged on the proximal end side of the first binding wire 41 to limit the perforation passing through the main envelope 12 on the inside of the wave trough bending to expand. In other embodiments, the binding wire can also be connected to the main wave coil, and the edge of the binding wire close to the steel sleeve is arranged to limit the movement of the binding wire relative to the main envelope by the steel sleeve.

[0097] As shown in Figure 7-8As shown, the main wave ring 11 is formed by connecting a plurality of single waves in sequence, and the main support 10 includes a main wave ring 11 arranged at the proximal end of the coated support 100, and the main wave ring 11 includes a first wave crest 1111, a first wave trough 1112 and a first wave rod 1113 connecting the first wave crest 1111 and the first wave trough 1112, and the first wave rod 1113 is used to tie the attachment 111, and the first through-hole 124 and the second through-hole 125 are respectively arranged on both sides of the extension direction of the first wave rod 1113, and the line where the straight line connecting the geometric center of the hole of the first through-hole 124 and the geometric center of the hole of the second through-hole 125 is located is defined as W1, and W is defined as 1 The intersection of the first wave rod 1113 is Q, and the tangent line passing through the point Q and the wave rod is defined as W2, wherein the angle α between W1 and W2 satisfies: 60°≤α≤90° (the angle between the two straight lines is in the range of 0° to 90°). When the vertical distances between the first through-hole 124 and the second through-hole 125 and the first wave rod 1113 are constant, if the 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 binding 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 wave coil 11, thereby reducing the force on the edge of the membrane hole, which may cause the membrane hole to expand.

[0098] In one embodiment, the linear membrane 122 includes a first linear membrane 122a and a second linear membrane 122b, the first linear membrane 122a is arranged on the proximal end side of the first perforation 124 and the second perforation 125, and the second linear membrane 122b is arranged on the distal end side of the first perforation 124 and the second perforation 125, and the angle β1 between the first linear membrane 122a and W1 satisfies: 0°≤β1≤20°, so that the first linear membrane 122a sets a limit on the proximal end side of the first perforation 124 and the second perforation 125 to avoid To avoid the possibility that the membrane hole of the first perforation 124 and the membrane hole of the second perforation 125 expand toward the proximal end side; the angle β2 between the second linear membrane 122b and W1 satisfies: 0°≤β2≤20° (for the convenience of identifying β1 and β2, the angle between the parallel lines of the linear membrane 122 and W1 is identified in the figure), so that the second linear membrane 122b can set a limit on the distal end side of the first perforation 124 and the second perforation 125, to avoid the possibility that the membrane hole of the first perforation 124 and the membrane hole of the second perforation 125 expand toward the distal end side.

[0099] The covered stent 100 can be implanted in a curved blood vessel. When the covered stent 100 is implanted in a curved blood vessel, the first side 10a of the main stent 10 is defined as the side that aligns with the lesser curvature of the blood vessel, and the second side 10b of the main stent 10 is defined as the side that aligns with the greater curvature of the blood vessel. Taking the curved configuration 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. The first side 10a is the side of the main stent 10 away from the arch branches (the lesser curvature side), and the second side 10b is the side of the main stent 10 closer to the arch branches (the greater curvature side).

[0100] like Figure 9-12 As shown, the stent graft 100 may further include a branch stent 50, which is connected to one axial side of the main stent 10, and the lumen of the branch stent 50 is connected to the lumen of the main stent 10. Figure 9 As 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 set in the middle position of the circumferential arc of the second side 10b; Figure 13 As shown, the main support 10 also includes a plurality of connectors 16, which connect two adjacent main wave coils 11. The connectors are arranged on the second side 10b of the main support 10. The connectors 16 can be formed by extending one end of a main wave coil 11 to the adjacent main wave coil 11, or can be formed by multiple separate connectors connecting two adjacent main wave coils 11 together along the axial direction. The connectors 16 are continuously arranged along the axial direction at the circumferential center of the second side 10b. The branch support 50 is arranged on the circumferential center axis of the second side 10b. Some connectors and the branch support 50 are arranged on the same axial line, so that the coated support 100 is convenient for bending toward the first side 10a and not convenient for bending toward the second side 10b. The connectors near the branch support 50 can be arranged on both sides of the axial direction of the branch support 50 to avoid the position of the branch support 50.

[0101] The main corrugation coil 11 includes high and low corrugations. When the stent graft 100 is placed in a curved blood vessel, the high and low corrugations are arranged at the bend of the stent graft 100. In this embodiment, the main corrugation coil 11 includes multiple high and low corrugations, each of which includes a plurality of continuous low-wave single corrugations arranged on the first side 10a and a plurality of continuous high-wave single corrugations arranged on the second side 10b. The low-waves between adjacent high and low corrugations are spaced relatively large in the axial direction, so that when the stent graft 100 is implanted in a curved blood vessel, it is easier to bend toward the first side 10a.

[0102] like Figure 9As shown, the main support 10 includes a proximal end segment 10c, a curved segment 10d and a distal end segment 10e from the proximal end to the distal end, that is, the curved segment 10d is closer to the distal end relative to the proximal end segment 10c, the flexibility of the first side 10a of the proximal end segment 10c is less than the flexibility of the first side 10a of the curved segment 10d, and the flexibility of the first side 10a of the distal end segment 10e is less than the flexibility of the first side 10a of the curved segment 10d, so that the curved segment 10d is easier to bend toward the first side 10a (flexibility here refers to the property of the coated support 100 that it is easier to bend, which can be set by adjusting the spacing distance between adjacent wave coils. The flexibility is greater at the position where the spacing distance between adjacent wave coils is larger; the corresponding flexibility can also be adjusted by setting a connector. The flexibility is smaller at the position where the connector is set).

[0103] Combine Figure 10 As shown, when the coated stent 100 is implanted in a curved blood vessel, the curved segment 10d bends toward the first side 10a, so that the curved segments 10d on the first side 10a are stacked. Since the capsule 30a is arranged on the first side 10a, if the capsule 30a is not provided with a fixed connection point at the proximal end segment 10c, then after the coated stent 100 is released, the proximal end side edge of the capsule 30a seriously exceeds the proximal end side of the main body coating 12 due to the stacking of the curved segments 10d, thereby affecting the blood flow at the inflow end of the coated stent 100, causing unnecessary risks.

[0104] like Figure 9 and Figure 11 Combine Figure 5 As shown, the binding attachment 111 includes a first binding attachment 111a and a second binding attachment 111b. The first binding attachment 111a is closer to the proximal end of the main frame 10 than the second binding attachment 111b. The envelope 30a is connected to the main frame 10 via a first binding line 41 and the first binding attachment 111a, and is connected to the main frame 10 via a second binding line 42. The envelope 30a is connected to the main frame 10. In one embodiment, the binding attachment 111a is connected to the first binding attachment 111a. Figure 11 As shown, the first binding attachment 111a is arranged on the first side 10a of the proximal end segment 10c. Since the position of the proximal end segment 10c changes only due to the bending of the curved segment 10d when the coated stent 100 is implanted in a curved blood vessel, the proximal end segment 10c itself is bent less, that is, the first side 10a of the proximal end segment 10c is less stacked, so the edge between the main body coating 12 and the corresponding capsule 30a portion from the perforation position corresponding to the first binding attachment 111a to the proximal end portion can be kept flush before and after implantation, thereby preventing the proximal side edge of the capsule 30a from seriously exceeding the proximal side of the main body coating 12, avoiding affecting the blood flow at the inflow end of the coated stent 100, as shown in FIG. Figure 12That is, at least one binding attachment 111 is provided on the first side 10a of the proximal end segment 10c, so that the capsule and the main stent are fixedly connected at least at one point in the proximal end segment. This ensures that the relative position of the capsule 30a portion at the proximal end side and the main stent 10 corresponding to the proximal end segment 10c remains almost unchanged before and after implantation, thereby preventing the proximal end edge of the capsule 30a from significantly extending beyond the proximal end side of the main covering 12 due to the overlap of the first side 10a of the curved segment 10d after implantation into a curved blood vessel.

[0105] In this embodiment, if Figure 11 As shown, the proximal end segment 10c includes the first main wave circle 11a and the second main wave circle 11b from the proximal end to the distal end. The first main wave circle 11a is a small wave circle with a smaller wave height than other main wave circles 11. The second main wave circle 11b can be a small wave circle with a smaller wave height. The distal end of the proximal end segment 10c is the circumferential surface where the trough of the second main wave circle 11b is located; the second main wave circle 11b can also be a high-low wave circle with equal wave peaks at the proximal end, and the first side 10a of the second main wave circle 11b is a low wave, and the second side 10b is a high wave, then the distal end of the proximal end segment 10c is the circumferential surface where the trough of the low wave of the second main wave circle 11b is located.

[0106] The curved section 10d includes the third main wave coil 11c and the fourth main wave coil 11d from the proximal end to the distal end, wherein the third main wave coil 11c and the fourth main wave coil 11d are both high-low wave coils, and the third main wave coil 11c can be a nearly flat high-low wave coil or a far-flat high-low wave coil, and the fourth main wave coil 11d can also be a nearly flat high-low wave coil or a far-flat high-low wave coil, so as to ensure that the axial spacing between adjacent wave coils on the first side 10a of the curved section 10d is larger than that of the proximal end section 10c or the distal end section 10e, so as to ensure the flexibility of the first side 10a of the curved section 10d, so that the curved section 10d of the coated bracket 100 is easier to bend toward the first side 10a; wherein, the nearly flat high-low wave coil refers to that the peaks of the high wave and the low wave on the proximal end side are flush, and the far-flat high-low wave coil refers to that the troughs of the high wave and the low wave on the distal end side are flush.

[0107] In this embodiment, the third main wave circle 11c is a nearly flat high and low wave circle, the fourth main wave circle 11d is a far flat high and low wave circle, and the axial spacing d1 between the trough of the first side 10a of the first main wave circle 11a and the wave peak of the first side 10a of the second main wave circle 11b is smaller than the axial spacing d2 between the low wave trough of the first side 10a of the second main wave circle 11b and the low wave peak of the first side 10a of the third main wave circle 11c; in this embodiment, the first binding line 41 is arranged on the wave rod or wave peak or wave trough of the first side 10a of the first main wave circle 11a, and the second binding line 42 is arranged on the wave rod or wave peak or wave trough of the first side 10a of the second main wave circle 11b, as shown in FIG. Figure 7-7bAs shown, the first main wave coil 11a and the second main wave coil 11b are the main wave coils 11 for connecting with the binding wire 40; in other embodiments, the first binding wire 41 is arranged on the wave rod or wave crest or wave trough of the first side 10a of the first or second main wave coil 11b, and the second binding wire 42 is arranged on the wave rod or wave crest or wave trough of the first side 10a of the third or fourth main wave coil 11d. At this time, the third main wave coil 11c connected to the first binding wire 41 includes a binding accessory 111, and the third main wave coil 11c connected to the second binding wire 42 includes a binding accessory 111. The third or fourth main wave coil 11d also includes a binding attachment 111; it is only necessary to ensure that at least one connection position is set on the first side 10a of the proximal end segment 10c for the binding line 40 to be fixedly connected, so that the relative position of the capsule 30a portion from the connection position to the proximal end side and the main stent 10 of the corresponding proximal end segment 10c remains almost unchanged before and after implantation, thereby avoiding the situation that the proximal side edge of the capsule 30a seriously exceeds the proximal side of the main body covering 12 due to the stacking of the first side 10a of the curved segment 10d after implantation into the curved blood vessel

[0108] like Figure 13-14a As shown, the main bracket 10 includes an annular support 13 and a window. The window is arranged on the side of the main bracket 10 for communicating with the branch bracket 50. The annular support 13 is arranged along the window and is made of a developing material for supporting the edge of the window and displaying the position of the branch bracket 50.

[0109] The branch stent 50 includes a first end 51, a middle section 52, and a second end 53. The first end 51 and the second end 53 are two opposite ends, and the middle section 52 is arranged between the first end 51 and the second end 53. The stent graft 100 also includes an annular connecting membrane 14, which connects the main stent 10 and the middle section 52 of the branch stent 50, thereby connecting the branch stent 50 to the main stent 10, and making the first end 51 of the branch stent 50 located in the lumen of the main stent 10, and the second end 53 of the branch stent 50 located outside the lumen of the main stent 10, as shown in FIG. Figure 14-14a shown.

[0110] The outer diameter of the branch stent 50 is smaller than the inner diameter of the annular support 13, and the radial width of the annular connecting membrane 14 is greater than the difference between the inner diameter of the annular support 13 and the outer diameter of the branch stent 50, so that the annular connecting membrane 14 can allow the branch stent 50 to float up and down (radially of the main stent 10), and at the same time, the branch stent 50 can swing 360° along its tubular circumference, so that the opening direction of the second end of the branch stent 50 away from the main stent 10 is adjustable, so that after the coated stent 100 is implanted in the blood vessel, when a guide wire is used to approach the branch blood vessel, the opening of the second end of the branch stent 50 is easier to align with the branch blood vessel opening, thereby reducing the influence of the complexity of the anatomical morphology on the correspondence between the opening of the second end of the branch stent 50 and the branch blood vessel opening. The annular connecting membrane connects the middle part of the branch stent 50, so that part of the branch stent 50 is located outside the main stent 10 and part is located inside the main stent 10. This can ensure that the second end of the branch stent 50 floats down to be flush with the main stent 10, and within the range of the annular support, the direction of the second end opening of the branch stent 50 is adjustable, which is more convenient to adapt to different anatomical shapes.

[0111] The present invention also provides a support system 700, such as Figure 15 Combine Figure 20-22 As shown, the stent system 700 includes the above-mentioned coated stent 100 and a conveyor 70. The conveyor 70 includes a sheath core assembly 71, a support rod 72, a sheath tube 73, a bundle diameter detachable 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 sequentially connected 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 along the axial direction. The support rod 72 is connected to the outside of the sheath core assembly 71. The conveyor 70 also includes a guide head 76. The guide head 76 is arranged at the distal end of the inner sheath core 711. The distal end of the support rod 72 and the proximal end of the guide head 76 are spaced apart to form a loading space for the coated stent 100. Figure 15 As shown, in order to conveniently display the structure inside the sheath 73, the figure shows the internal components of the sheath 73 (the coated stent is omitted).

[0112] like Figure 16-16a As shown, the support rod 72 includes a first channel 721 and a second channel 722 that pass through the axial direction. The first channel 721 is for the sheath core assembly 71 to pass through the axial direction, and the second channel 722 is for the bundle diameter guide wire 741 to pass through the axial direction. Figure 16 In other embodiments, the support rod 72 may further include a third channel 723 for the pre-installed catheter 79 to pass through axially. Figure 16a shown.

[0113] like Figure 17 Combine Figure 15As shown, the bundle diameter detachable part 74 may include a bundle diameter guide wire 741, and the distal end of the bundle diameter detachable part 74 is sutured along the limiting holes 31 on the two long side edges of the capsule 30a so that the capsule 30a can be opened to release the stent. The proximal end of the bundle diameter detachable part 74 is connected to a safety buckle 743, and the safety buckle 743 is detachably fixed to the handle assembly 75 to prevent the coated stent 100 from being placed by mistake.

[0114] like Figure 17 As shown, the guide wire 741 is used to cross and pass through the holes near the edges of the two long sides of the capsule 30a in sequence along the axial direction, so as to wrap the stent graft 100 in the capsule 30a, so as to radially compress the stent graft 100 in the capsule 30a, and put the stent graft 100 in a radially compressed bundled diameter state. The distal end of the guide wire 741 is used to cross and pass through the limiting holes 31 set at the edges of the two long sides of the capsule 30a in sequence along the axial direction, so as to enclose the capsule 30a into a tubular body, so as to radially compress the stent graft 100 and gather it in the capsule 30a, and the guide wire 741 can be withdrawn to release the restriction of the guide wire 741 on the limiting holes 31, so as to release the stent graft 100 from the compressed state, so as to release the constraint of the capsule 30a on the stent graft 100. The proximal end of the bundle guide wire 741 is connected with a pull ring as a safety buckle 743, which is releasably fixed to the handle assembly 75. When the coated stent 100 needs to be released, the safety buckle 743 is first released from the handle assembly 75, and then the safety buckle 743 is pulled back, the capsule 30a opens, and the radial restraint on the coated stent 100 is released, allowing the coated stent 100 to expand naturally.

[0115] like Figure 17 As shown, the stent system 700 also includes a branch sheath 77, which includes a wrapping portion 771, a hook 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 configured as a wrapping film with one end open and the other end sealed. The end of the wrapping portion 771 close to the main stent 10 is an open structure, and the end of the wrapping portion 771 away from the main stent 10 is a closed structure. The hook portion 772 is disposed at the end of the wrapping portion 771 close to the main stent 10, and the branch guide wire 773 is disposed at the end of the wrapping portion 771 away from the main stent 10. The hook portion 772 includes a looped line for passing the guide wire 741 or the detachable suture structure 742, so that the branch sheath 77 remains connected and fixed to the main stent 10 before the envelope 30a is opened to release the main stent 10. The branch guide wire 773 is used to assist the branch stent 50 of the coated stent 100 in accurately aligning with the branch vessel orifice.

[0116] In other embodiments, Figure 18-19As shown, the detachable member 74 may also include a detachable suture structure 742, which axially passes through the holes near the edges of the two long sides of the envelope 30a to radially compress the stent graft 100 within the envelope 30a. The detachable member 74 is not limited here, and only needs to cooperate with the envelope 30a to achieve radial contraction and release of the stent graft 100. Figure 18 As shown, the detachable suture structure 742 includes a constraint segment 7421 and a lead segment 7422. The constraint segment 7421 axially sutures the two long side edges of the envelope 30a to form the envelope 30a into a tubular structure, so as to facilitate the radially compressed coated stent 100 to be confined within the envelope 30a. The lead segment 7422 is formed by the portion of the constraint segment 7421 extending outside the envelope 30a. Pulling the lead segment 7422 can release the constraint of the constraint segment 7421 on the two long sides of the envelope 30a, so that the envelope 30a is opened and the radial contraction of the coated stent 100 is released. Figure 19 shown.

[0117] In other embodiments, a branch sheath may not be provided, but a pre-buried guide wire (not shown) may be provided. The support rod 72 includes a channel for the pre-buried guide wire to pass axially, and then the pre-buried guide wire is used to select the branch vessel opening. Since it is difficult to directly select the branch vessel opening with a single guide wire, the pre-buried guide wire can be captured by a guide wire catcher to enter the branch vessel.

[0118] A branching access can be established in advance by using a guide wire along the branch for the branching guide wire 773 to pass through, or by using a guide wire catcher (not shown) to catch the branching guide wire 773 from the distal end of the conveyor 70, so that one end of the branching guide wire 773 can be caught and taken out of the body along the branch vessel, so that the branch stent 50 can be accurately positioned at the branch vessel orifice. After the stent graft 100 is accurately released, an external extension stent 90 can be implanted as needed, so that one end of the extension stent 90 (not shown) (close to the branch stent 50) is sleeved into the branch stent 50, and the other end of the extension stent 90 (away from the branch stent 50) is placed in the branch vessel.

[0119] like Figure 15 As shown, the handle assembly 75 includes a fixed handle 751, a sliding handle 752, and a wing 753. The proximal end of the fixed handle 751 includes a guide rail 7511 extending toward the proximal end. The proximal end of the sheath 73 is connected to the sliding handle 752. The sliding handle 752 is disposed on the proximal side of the fixed handle 751 around the guide rail 7511. Thus, the sliding handle 752 slides along the guide rail 7511 to drive the sheath 73 backward, thereby releasing the luminal stent from the distal end of the sheath 73. The wing 753 is disposed on the proximal side of the catheter. A channel is defined in the wing 753 and communicates with a channel in the support rod 72 for allowing a pre-placed catheter to pass through, thereby facilitating operation of the pre-placed catheter.

[0120] like Figure 20-22 As shown, the conveyor 70 also includes a rear release structure, which is used to hook the first bare wave ring 20, thereby realizing the rear release of the first bare wave ring 20 at the proximal end of the coated stent 100. The conveyor 70 includes a clamping member 78, which is connected to the distal end of the outer sheath core 712; the clamping member 78 includes a plurality of claws 781 and a connecting portion 782, and the proximal end of the guide head 76 is provided with a clamping portion 761 and a clamping groove 762; a plurality of claws 781 are radially dispersed from the connecting portion 782 toward the distal end, and the connecting portion 782 fixes the plurality of claws 781 to the distal end of the outer sheath core 712 at intervals, wherein the plurality of claws 781 can be respectively engaged with the clamping member 781. The slots 762 are matched one by one; the clamping portion 761 is provided at the distal end of the clamping slots 762, and the clamping portion 761 includes a clamping surface 7611 and a clamping step 7612. The inner circumference of the sheath 73 is sleeved on the clamping surface 7611, and the distal end surface of the sheath 73 abuts against the clamping step 7612, so that the guide head 76 can be fitted into the distal end of the sheath 73, and the fitting portion of the claw 781 and the clamping slot 762 is received into the sheath 73. It can be understood that the fitting of the clamping member 78 and the clamping slot 762 forms the above-mentioned releasable rear release structure, that is, the rear release structure includes the clamping member 78 and the clamping slot 762, the clamping member 78 and the clamping slot 762 are fitted together to form a closed state, and the clamping member 78 and the clamping slot 762 are separated from each other to form an open state. When in the closed state, the rear release structure can temporarily fix the first bare wave coil 20 at the proximal end of the coated stent 100 before the rear release.

[0121] Taking the method of using a branch guide wire 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 in this embodiment for implantation in the aortic arch is briefly summarized:

[0122] A guide wire (not shown) is introduced along the branch vessel access route, from the proximal end to the distal end of the aorta, and finally led out from the femoral artery incision. Then, the guide wire is passed through the branch vessel access route into the guide catheter 81 and led out from the femoral artery. The guide wire is then removed, thereby forming a Figure 23 The guide catheter 81 passage is shown;

[0123] The super-hard guide wire 82 is introduced into the ascending aorta, and the stent system 700 is introduced along the super-hard guide wire 82. The stent system 700 is slowly introduced into the human body along the super-hard guide wire 82. At the same time, the branch guide wire 773 in the stent system 700 is introduced from the femoral artery to the branch blood vessel along the guide catheter 81. The branch guide wire 773 is pulled out from the guide catheter 81, and the branch guide wire 773 and the guide catheter 81 are pulled together to introduce the distal end of the stent system 700 to the straight section near the arch. Figure 24 shown.

[0124] Continue to push the stent system 700 along the super-hard guide wire 82, so that the distal end of the stent system 700 is delivered to the arch of the aorta for preliminary positioning of the stent system 700, and withdraw the sheath 73 of the conveyor 70 to the distal end of the main stent 10, so that the coated stent 100 that is bound by the envelope 30a is completely exposed from the sheath. Since the coated stent 100 is wrapped by the envelope 30a and radially bound, the stent system 700 can still be adjusted along the super-hard guide wire 82 after the sheath 73 is withdrawn, thereby positioning the coated stent 100. 00 for precise positioning, the branch stent 50 is exposed after the sheath 73 is withdrawn. At this time, the branch guide wire 773 is pulled and the main stent 10 is pushed and adjusted. Under 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 ring line (hook part 772) and the bundle diameter guide wire 741 hooked with each other, a certain external force can be used. Through the traction force of the branch guide wire 773, the branch opening of the coated stent 100 can be more accurately aligned with the branch blood vessel, such as Figures 25-26 shown.

[0125] like Figures 27-28 As shown, the bundle guide wire 741 or the lead segment 7422 of the suture structure of the stent system 700 is pulled backward, and the main stent 10 is unfolded and attached to the wall from the proximal end to the distal end. The bundle guide wire 741 or the suture structure is completely withdrawn from the coated stent 100, the capsule 30a is completely opened, and the main stent 10 is basically completely attached to the wall (except for the first bare wave ring 20 at the proximal end being hooked by the rear release structure). In addition, since the bundle guide wire 741 or the suture structure is completely released and pulled out, the mutual hooking and fixation between the annular line of the branch sheath 77 and the capsule 30a of the main stent 10 is released, and the branch guide wire 773 can be easily pulled out. At this time, the branch stent 50 is fully unfolded and attached to the branch blood vessel, as shown in FIG. Figure 29 shown.

[0126] The present invention also provides another support system 700, such as Figure 30 As shown, the stent system 700 includes the above-mentioned stent graft 100, a delivery device 70 and a pre-placed catheter 79. The delivery device 70 includes the above-mentioned sheath core assembly 71, support rod 72, sheath tube 73, bundle diameter detachable member 74 and handle assembly 75. That is, the stent system 700 does not include the above-mentioned branch sheath 77, but includes other structures. In addition, as Figures 31-33As shown, the stent system 700 further includes a pre-placed catheter 79, which extends along the lumen of the main stent 10 and is axially movable relative to the main stent 10. The distal end of the pre-placed catheter 79 can pass through the branch stent 50. The provision of the pre-placed catheter allows direct access to the branch vessel using the pre-placed catheter, eliminating the need to puncture or incise the other end of the branch vessel to capture the branch guidewire, reducing patient pain and preventing the guidewire from becoming entangled with the super-hard guidewire of the main stent during the capture process. This reduces the surgical difficulty and duration for the surgeon during branch selection.

[0127] The stent graft includes a semi-constrained structure, which includes a wrapping member that can be configured as a membrane or a binding wire. Both the membrane and the binding wire can be used to radially constrict the main stent. When a pre-placed catheter is provided, the semi-constrained structure can achieve semi-constraint not only by utilizing the membrane and the releasable binding member, but also by utilizing the corresponding wave ring spacing of the binding wire along the circumference in conjunction with the binding wire to achieve semi-constraint. Wherein, the naturally straightened length W0 of the binding wire and the circumference of the stent graft 100 in its naturally expanded state at the corresponding position of the binding wire are C, then the relationship between W0 and C satisfies: W0 ≤ C / 4.

[0128] Combine Figures 31-33 As shown, the pre-placed catheter 79 includes a straight section 791 and a pre-bent section 792. The pre-bent section 792 is disposed at the distal end of the straight section 791. The connection between the straight section 791 and the pre-bent section 792 forms a bending point. The pre-bent angle γ of the pre-bent section 792 relative to the straight section 791 satisfies the following range: 0° < γ ≤ 60°. The pre-bent angle γ is the angle between the straight line on which the straight section 791 lies and the tangent line to the distal endpoint T at the center of the greater curvature of the pre-placed catheter 79. A developing element 793 is provided at the distal end of the pre-placed catheter 79 to display the position of the distal end of the pre-placed catheter 79, facilitating its insertion into a branch vessel. The proximal end of the pre-placed catheter 79 extends beyond the proximal end of the handle assembly 75 and has a margin to facilitate adjustment of the pre-placed catheter 79 for insertion into a branch vessel and to facilitate the insertion of a guidewire along the pre-placed catheter 79 into the branch vessel.

[0129] The support rod 72 further includes a third channel 723, through which the pre-installed catheter 79 passes axially. Figure 16a shown.

[0130] like Figure 32As shown, the proximal end side of the main support 10 includes a gap 15, and at least part of the pre-bent section 792 of the pre-placed catheter 79 exceeds the proximal end side of the main support 10. In this embodiment, the first bare wave ring 20 is hooked on the rear release structure of the conveyor 70, and the gap 15 is formed due to radial compression between the wave rods of the rear release structure where the first bare wave ring 20 is hooked; in the conveying state, at least 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-placed catheter 79 exposed from the coated stent is retracted in the sheath 73, the pre-bent shape of the pre-placed catheter 79 is prevented from being straightened due to the squeezing of the coated stent 100 and the sheath 73.

[0131] Another stent system 700 is used for surgical implantation in the aortic arch and can be combined with Figures 30-33 The conveyor diagram is briefly summarized as follows:

[0132] like Figure 34 As shown, a super-hard guide wire 82 is introduced into the ascending aorta to establish an access channel to the aortic arch, and then the stent system 700 is introduced along the super-hard guide wire 82. The stent system 700 is slowly introduced into the human body along the super-hard guide wire 82 until the distal end of the stent system 700 is introduced into the descending aorta, as shown in FIG. Figure 35 shown.

[0133] 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, which is contracted by the envelope 30a, is exposed outside the sheath 73 in a state of being wrapped by the envelope 30a. Since the coated stent 100 is wrapped by the envelope 30a and radially contracted, the stent system 700 can still be adjusted along the superhard guide wire 82 after the sheath 73 is withdrawn, so as to accurately position the coated stent 100. The branch stent 50 and the pre-placed catheter 79 are exposed after the sheath 73 is withdrawn. Figure 36 As shown;

[0134] The proximal end of the pre-placed catheter 79 is rotated to separate the pre-bent section 792 of the pre-placed catheter 79 from the gap 15 of the first bare wave ring 20, and then the pre-placed catheter 79 is pushed and inserted into the branch vessel (the left subclavian artery is shown in the figure), and a branch hard guide wire 83 is introduced into the branch vessel along the pre-placed catheter 79. Figures 37-38 As shown;

[0135] like Figure 39 As shown, the stent system 700 is pushed forward until the annular support 13 is facing the left subclavian artery, and then the guide wire 741 is withdrawn, so that after the envelope 30a is opened, the coated stent 100 naturally expands to be basically attached to the wall, as shown in FIG. Figure 40 As shown;

[0136] like Figure 41As shown, the first bare wave coil 20 is released, the pre-placed catheter 79 and the delivery device 70 are withdrawn, an external extension stent 90 is implanted along the branch hard guide wire 83, and the branch hard guide wire 83 is withdrawn, as shown in FIG. Figure 42 shown.

[0137] 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 insertion of the branch hard guidewire 83 into the branch blood vessel to establish a branch pathway, thereby avoiding the problem of difficulty in selecting the branch blood vessel using the guidewire, and also eliminating the need to open the upper limb access route while avoiding the problem of guidewire entanglement, thereby greatly reducing the operation time; moreover, 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 excessively large branch angles that are difficult to select. After the pre-placed catheter 79 is inserted into the branch blood vessel, the difficulty of inserting the branch hard guidewire 83 into the branch blood vessel can be reduced, thereby reducing the operation time.

[0138] Due to the coordinated arrangement of the envelope 30a and the pre-placed catheter 79, when the coated stent 100 is wrapped in the envelope 30a, a narrow and relatively uniform axial channel 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.

[0139] 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 is set to satisfy: W≤C / 4; this makes the compression radius of the coated stent in the semi-constrained state smaller, that is, the radial compression degree of the coated stent is maintained at a larger 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 waves of the radially compressed coated stent are stacked crowded, the preset catheter is pre-set in the coated stent, and due to the soft wrapping of the envelope, it can provide a radial soft buffer, reduce the friction between the preset catheter and the stacked main body waves, and still ensure the smoothness of delivery when axial delivery is required; 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-placed catheter 79, which can avoid the pre-placed catheter 79 from bending in the channel during the delivery process; in addition, the radial compression of the coated stent 100 by the envelope 30a is smaller than the compression of the coated stent 100 by the sheath 73, and the friction force on the pre-placed catheter 79 is smaller, and because the wrapping of the main stent 10 by the envelope 30a is uniform 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 ring 11, resulting in a larger channel, and the pre-placed catheter 79 is bent at a position with a larger channel space.

[0140] It can be understood that, in order to make the radial compression degree of the envelope larger, the relationship between the width W of the envelope 30a and the lumen circumference C of the stent graft 100 at the corresponding position can also satisfy W≤C / 5; that is, even if the envelope wraps the stent graft, the channel space of the stent graft after radial compression is small, and since the envelope is a flexible film, the radial compression of the stent graft by the envelope is soft wrapping. When the pre-catheter is pre-positioned in the space in the axial direction, the pre-catheter can also smoothly slide in the axial direction along the narrow space, and at the same time, the envelope radially extrudes the stent graft, which can avoid the bending of the pre-catheter in the channel space.

[0141] It can be understood that, in one of the embodiments, the stent system 700 can also include a pre-guide wire, which is arranged in the pre-catheter 79 and extends along the axial channel of the pre-catheter 79; the distal end of the pre-guide wire is beyond the bending point of the pre-bent section 792 and the straight tube section 791, which prevents the pre-bent section 792 from being embedded in the gap 15 and keeps the bending of the pre-bent section 792, so that the passage of the bending point is narrowed, thereby causing the guide wire to be difficult to pass through the narrow passage of the bending point during the subsequent surgery process, thereby increasing the difficulty of the surgery.

[0142] In other embodiments, the stent graft 100 provided by the application can also include an embedded stent 60, so that the stent graft can be used for the case where an aneurysm involves the left common carotid artery, such as Figures 43-44 As shown, the stent graft 100 also includes another window, and the embedded stent 60 is arranged on the distal side of the branch stent 50, and 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 located in the left common carotid artery, the corresponding window of the embedded stent 60 can face the left subclavian artery.

[0143] As Figures 43-44 provided, the release process of the corresponding stent system of the stent graft is as Figures 45-50 shown, and the stent system is used for the surgical method of implanting in the aortic arch, which can be combined with Figures 30-33 The delivery device is simply summarized as follows:

[0144] The process of establishing the aortic access is as Figures 34-37The process is consistent with that of the embodiment of the present invention, that is, a super-hard guide wire 82 is used to introduce the stent into the ascending aorta to establish an access channel to the aortic arch, and then the stent system is introduced along the super-hard guide wire 82. The stent system is slowly introduced into the human body along the super-hard guide wire 82 until the distal end of the stent system is introduced into the descending aorta; the sheath 73 is retracted to the distal end of the main stent 10 by retracting the sliding handle 752, so that the main stent 10 that is contracted by the envelope 30a is exposed outside the sheath 73 in a state of being wrapped by the envelope 30a. Since the coated stent 100 is wrapped by the envelope 30a and radially contracted, after the sheath 73 is retracted, the stent system can still continue to adjust along the super-hard guide wire 82, so as to accurately position the coated stent 100, and the branch stent 50 and the pre-placed catheter 79 are exposed after the sheath 73 is retracted.

[0145] Further, the proximal end of the pre-placed catheter 79 is rotated and slightly withdrawn to allow the pre-bent section 792 of the pre-placed catheter 79 to escape from the gap 15 of the first bare wave ring 20, and then the pre-placed catheter 79 is pushed and inserted into the left common carotid artery. A branch hard guide wire 83 is introduced along the pre-placed catheter 79 into the branch blood vessel, as shown in FIG. Figure 45 As shown;

[0146] like Figure 46 As shown, the stent system is pushed forward until the annular support 13 faces the left common carotid artery, and then the guide wire 741 is withdrawn, so that after the capsule 30a is opened, the coated stent 100 naturally expands to be basically attached to the wall, as shown in FIG. Figure 47 As shown;

[0147] like Figure 48 As shown, the first bare wave coil 20 is released, the pre-placed catheter 79 and the delivery device 70 are withdrawn, an external extension stent 90 is implanted along the branch guide wire 83, and the branch guide wire 83 is withdrawn, as shown in FIG. Figure 49 As shown;

[0148] like Figure 50 As shown, an external small stent 91 is implanted along the embedded stent 60, and one end of the small stent 91 partially overlaps and matches the embedded stent, so that the small stent 91 extends to the left subclavian artery.

[0149] It is understandable that in other embodiments, the covered stent may also include two embedded stents, so as to be used in situations where the aortic aneurysm involves the three branches of the aortic arch. The surgical procedure can refer to the above process, so that the branch stents correspond to the brachiocephalic artery, which will not be repeated here.

[0150] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0151] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A stent graft, characterized in that: The coated stent includes a main body stent and a wrapping piece, 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 wrapping piece is connected to one side of the main body stent, the wrapping piece can releasably wrap the main body stent so that the main body stent is radially compressed or released, the width of the wrapping piece at a certain position is defined as W, and the circumference of the coated stent at a position corresponding to the width W of the wrapping piece in a naturally expanded state is defined as C, then the relationship between W and C satisfies: W≤C / 4.

2. The stent graft according to claim 1, wherein: The wrapping piece is connected to the main body support by a binding wire, and the main body support includes a binding accessory, and the binding accessory includes a part of the main body wave ring or includes a binding wire. The binding accessory extends along the main body covering, and the main body covering includes a first perforation and a second perforation, and the first perforation and the second perforation are respectively arranged on both sides of the extension direction of the binding accessory, and the binding wire passes through the first perforation and the second perforation and crosses the binding accessory.

3. The stent graft according to claim 2, wherein: The 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 wave-shaped ring, and the binding wire is connected to the main wave coil, and the binding wire is close to the edge of the steel sleeve.

4. The stent graft according to claim 2, wherein: The main body covering film includes a linear film, and the linear film is wound along the circumference of the main body covering film; The binding wire is connected to the wave rod of the main wave coil, and at least one linear film is respectively provided on the proximal end side and the distal end side of the binding wire; Alternatively, the binding wire is connected to the crest of the main wave rod, and at least one linear membrane is provided on the distal end side of the binding wire; Alternatively, the binding wire is connected to the trough of the main wave rod, and at least one linear membrane is provided on the distal end side of the binding wire.

5. The stent graft according to claim 2, wherein: The main body coating includes a linear film, which is wound along the circumference of the main body coating; the shortest distance L1 of the linear film to the first perforated edge in the axial direction satisfies: L1≤3mm, and / or the shortest distance L2 of the linear film to the second perforated edge in the axial direction satisfies: L2≤3mm.

6. The stent graft according to claim 5, characterized in that: The wrapping piece includes a buffer piece, a third perforation and a fourth perforation. The buffer piece extends along the plane where the wrapping piece is located. The third perforation and the fourth perforation are respectively arranged on both sides of the extension direction of the buffer piece. The 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 piece before being tied.

7. The stent graft according to claim 1, wherein: 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 wrapping piece is connected to the first side of the main stent by a binding wire, 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 provided on the first side of the proximal end segment.

8. The stent graft according to claim 7, wherein: 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 includes a first binding wire and 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.

9. A stent system, comprising the stent graft according to claim 7 or 8, 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 bundle diameter 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 connected from the inside to the outside, and the support rod is connected to 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 bundle diameter member cooperates with the wrapping member to realize radial contraction and release of the coated stent.

10. The support system according to claim 9, wherein: The stent system further comprises a pre-placed catheter, which extends along the lumen of the main stent, and the distal end of the pre-placed catheter can pass through the branch stent.

11. The support system according to claim 10, wherein: The pre-placed catheter includes a straight tube section and a pre-bent section, and the pre-bent section is arranged on the distal end side of the straight tube section.

12. The support system according to claim 11, wherein: At least part of the pre-bent section of the pre-placed catheter extends beyond the proximal end of the main stent, and the proximal end of the main stent includes a gap. In the delivery state, at least part of the pre-bent section is embedded in the gap to maintain the pre-bent shape of the pre-bent section.

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