Aorta covered stent and stent system

Abstract

The invention relates to an aorta covered stent and stent system.The covered stent comprises a main stent body and a branch stent body, the main stent body comprises a first side and a second side, the branch stent body is located on the first side, and the main stent body comprises a first bare wave ring, a main wave ring and a main covering film; the main body covering film is arranged on the main body wave ring, the first bare wave ring is connected with the near end part of the main body covering film, the far end part of the first bare wave ring comprises a first far end positioned on the first side and a second far end positioned on the second side, and the first far end and the second far end are positioned on different radial cross sections. According to the aorta covered stent structure provided by the invention, the near end of the main body stent can still be released by directly selecting the guide wire into the arch branch, so that the winding problem between the prefabricated branch guide wire and the main body guide wire can be avoided, the problem that the prefabricated guide wire is not easy to select can also be avoided, the overall operation time is shortened, and the operation risk is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and particularly relates to an aortic covered stent and a stent system. Background Art

[0002] Aortic aneurysms and aortic dissections are currently diseases that seriously endanger human life safety. If not actively treated, the aortic aneurysm and dissection will continue to grow and finally rupture, causing serious complications and even leading to the death of the patient. With the continuous increase in the number of patients with hypertension, hyperlipidemia, and hyperglycemia, the current incidence of aortic aneurysms and aortic dissections is also increasing significantly.

[0003] Traditional open surgical treatments for aortic aneurysms and aortic dissections involving branch vessels have the disadvantages of large trauma, high mortality, long operation time, high incidence of postoperative complications, and high operation difficulty. Endovascular treatment, on the other hand, has the characteristics of small trauma, few postoperative complications, short operation time, and low operation difficulty, and has gradually become the main method for treating aortic aneurysms and aortic dissections. By implanting a covered stent in the aorta, the vascular lesion is isolated outside the covered stent, and the blood flow is restricted to flow through the inside of the covered stent, thereby achieving the purpose of protecting the blood vessel. In a traditional aortic covered stent, generally along the main guide wire selected into the main lumen, after the main body part is released, the branch on the aortic arch is selected through a prefabricated branch guide wire. Entanglement is likely to occur between the two guide wires. When the branch guide wire selects the branch on the aortic arch, a snare on the upper limb approach is needed to snare the branch guide wire, so as to snare the branch guide wire into the branch on the aortic arch to complete the selection of the branch on the aortic arch. During the operation, the selection of the branch guide wire is difficult, which will prolong the operation time and increase the operation risk. Summary of the Invention

[0004] One technical problem solved by the present invention is how to set the structure of an aortic covered stent to reduce the number of guide wire selections on the premise of realizing the complete release of the main stent.

[0005] The present invention provides an aortic covered stent, which includes a main stent and a branch stent. The main stent includes a first side and a second side. The branch stent is located on the first side. The main stent includes a first bare wave ring, a main body wave ring, and a main body covering film. The main body covering film is arranged on the main body wave ring. The proximal end of the first bare wave ring is connected to the main body covering film. The distal end of the first bare wave ring includes a first distal end located on the first side and a second distal end located on the second side. The first distal end and the second distal end are located in different radial cross-sections.

[0006] In one embodiment, the proximal end of the main body covering film is in an inclined incision shape.

[0007] In one embodiment, the distal end portion of the second side of the first bare wave loop axially extends beyond the distal end portion of its first side, such that the distal end face of the first bare wave loop is of an inclined cut type.

[0008] In one embodiment, the first bare wave loop includes a foldable portion, a support portion, and an axial positioning portion in the circumferential direction; the foldable portion is close to the first side, the axial positioning portion is close to the second side, and the support portion is connected between the foldable portion and the axial positioning portion; the foldable portion includes a first waveform unit; the axial positioning portion includes a second waveform unit; the support portion includes a third waveform unit; the third waveform unit is respectively connected to the first waveform unit and the second waveform unit, and the wave height of the third waveform unit is less than the wave height of the first waveform unit, or / and the wave height of the third waveform unit is less than the wave height of the second waveform unit.

[0009] In one embodiment, the third waveform unit includes a first wave rod and a second wave rod, and the range of the included angle α between the first wave rod and the second wave rod satisfies: 46° ≤ α ≤ 145°.

[0010] In one embodiment, the first bare wave loop includes a foldable portion, a support portion, and an axial positioning portion in the circumferential direction; the foldable portion is close to the first side, the axial positioning portion is close to the second side, and the support portion is connected between the foldable portion and the axial positioning portion; the foldable portion includes a first waveform unit; the axial positioning portion includes a second waveform unit; the support portion includes a first inclined rod, and the first inclined rod is located between the first waveform unit and the second waveform unit.

[0011] In one embodiment, the support portion further includes a third waveform unit, the first inclined rod is connected to the third waveform unit, and both the first inclined rod and the third waveform unit are located between the first waveform unit and the second waveform unit.

[0012] In one embodiment, the first bare wave loop includes a foldable portion, a support portion, and an axial positioning portion in the circumferential direction; the foldable portion is close to the first side, the axial positioning portion is close to the second side, and the support portion is connected between the foldable portion and the axial positioning portion; the connection point between the foldable portion and the support portion is a first connection point, the first connection point is a first wave valley, and the first wave valley is movably connected to the main body film, facilitating the relative sliding of the first wave valley with respect to the main body film and not exceeding the proximal end of the main body film.

[0013] In one embodiment, the distal end portion of the distal end of the second side of the first bare wave loop axially extends beyond the distal end portion of its first side; the first bare wave loop includes a first waveform unit, a second waveform unit, and a third waveform unit, the first waveform unit is close to the first side, the second waveform unit is close to the second side, and the third waveform unit is located between the first waveform unit and the second waveform unit; an axial line passing through the midpoint of the first side and an axial line passing through the midpoint of the second side form a projection plane, and the projections of the first waveform unit and the second waveform unit on the projection plane are in the shape of a parallelogram or a trapezoid.

[0014] The present invention also provides a stent system, the stent system includes a delivery device and the covered stent as described above, the delivery device includes a sheath core assembly and a sheath tube, the sheath core assembly penetrates into the distal end of the main stent and exits from the branch stent, and the first bare wave loop is partially folded and loaded into the sheath tube as a whole.

[0015] In one embodiment, the delivery device further includes a guide head. Define the axial distance from the proximal side connection point of the branch stent to the proximal end of the main body covering film as L5, and define the overall axial length of the branch stent as L6. Among them, L5 and L6 satisfy: L6 > L5. In the stent system, the branch stent is closer to the guide head axially than the proximal end of the main stent.

[0016] In one embodiment, the free end of the foldable portion and the proximal end of the axial positioning portion do not interfere with each other, or the free end of the foldable portion presses against the outside of the axial positioning portion.

[0017] One technical effect of an embodiment of the present invention is: to provide an aortic covered stent structure, by directly selecting the guide wire into the branch above the aortic arch, the release of the proximal end of the main stent can still be carried out, which can solve the problem of winding between the two guide wires caused by the need to prefabricate the branch guide wire and the main guide wire in the prior art, and can also avoid the problem that it is not easy to select the prefabricated guide wire, reduce the overall operation time, and reduce the surgical risk. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a side view of the covered stent provided by Embodiment 1 of the present invention;

[0019] Figure 2 It is a side view of the first bare wave loop provided by Embodiment 1 of the present invention;

[0020] Figure 3 It is a schematic diagram of the side view of the first bare wave loop provided by Embodiment 1 of the present invention on the projection plane S;

[0021] Figure 4Schematic diagram of the structure of the covered stent provided in Embodiment 1 of the present invention;

[0022] Figure 5 Schematic diagram of the structure of the first bare wave ring provided in Embodiment 1 of the present invention;

[0023] Figure 6 Schematic diagram of the structure of the first bare wave ring from another perspective provided in Embodiment 1 of the present invention;

[0024] Figure 6a Schematic diagram of the first bare wave ring after the wave crest of the second waveform unit along the middle line of the second side is axially cut and laid flat on a plane provided in Embodiment 1 of the present invention;

[0025] Figure 7 is Figure 1 the left view shown;

[0026] Figure 8 Schematic diagram of the connection between the first wave trough and the main body covering film provided in Embodiment 1 of the present invention;

[0027] Figure 9 Schematic diagram of the connection between the first wave trough and the main body covering film in other embodiments provided in Embodiment 1 of the present invention;

[0028] Figure 10 is Figure 9 the schematic diagram of the main body covering film when the first wave trough is omitted;

[0029] Figure 11 Schematic diagram of the connection between the first wave trough and the main body covering film in other embodiments provided in Embodiment 1 of the present invention;

[0030] Figure 12 is Figure 1 the enlarged view of the proximal end of the main body stent in;

[0031] Figure 13 Schematic diagram of the covered stent in other embodiments provided in Embodiment 1 of the present invention;

[0032] Figure 14 Schematic diagram of the stent system of the branch stent including a semi-restrained structure provided in Embodiment 1 of the present invention;

[0033] Figure 15 is Figure 14 the enlarged view of the semi-restrained structure of the branch stent in;

[0034] Figure 16 Schematic diagram of the process of loading the covered stent provided in Embodiment 1 of the present invention into the sheath tube (the first bare wave ring has not been restrained yet);

[0035] Figure 17Schematic diagram of the process of loading the covered stent provided in Embodiment 1 of the present invention into the sheath (the foldable part is partially folded and to be constricted);

[0036] Figure 18 Schematic diagram of the process of loading the covered stent provided in Embodiment 1 of the present invention into the sheath (the foldable part is folded, the support part is opened and radially compressed together with the axial positioning part, and the axial positioning part is constricted in the sheath);

[0037] Figure 19 Schematic diagram of the process of loading the covered stent provided in Embodiment 1 of the present invention into the sheath (the first bare wave ring is entirely constricted in the sheath);

[0038] Figure 20 Schematic diagram of the process of loading the covered stent provided in Embodiment 1 of the present invention into the sheath (loading of the covered stent into the sheath is completed);

[0039] Figure 21 Schematic diagram of the structure of the guide wire selected into the left subclavian branch artery to be implanted in the stent system provided in Embodiment 1 of the present invention;

[0040] Figure 22 Schematic diagram of the stent system provided in Embodiment 1 of the present invention being delivered along the guide wire to the left subclavian branch artery;

[0041] Figure 23 For relative Figure 22 Schematic diagram of the sheath being retracted relative to the third imaging member approaching the first imaging member;

[0042] Figure 24 For relative Figure 23 Schematic diagram of the sheath being continuously retracted to make the third imaging member move away from the first imaging member and approach the second imaging member;

[0043] Figure 25 For relative Figure 24 Schematic diagram of the foldable part being released from the sheath (the support part is to be released);

[0044] Figure 26 For relative Figure 25 Schematic diagram of the first bare wave ring being released from the sheath (the distal end of the main stent is to be released);

[0045] Figure 27 For relative Figure 26 Schematic diagram of the entire main stent being released from the sheath;

[0046] Figure 28 For relative Figure 27 The second bare wave ring of the branch stent is separated from the sheath core and completely released;

[0047] Figure 29Schematic diagram of another covered stent provided in Embodiment 1 of the present invention;

[0048] Figure 30 Schematic diagram of yet another covered stent provided in Embodiment 1 of the present invention;

[0049] Figure 31 For Figure 29 Schematic diagram of the covered stent being delivered along a guide wire to the left common carotid artery branch;

[0050] Figure 32 Schematic diagram of the proximal end of another covered stent provided in Embodiment 2 of the present invention;

[0051] Figure 33 For Figure 32 Schematic diagram of the structure of the first bare stent and the positioning wave ring in

[0052] Figure 34 For Figure 33 Schematic diagram of a combination mode of the first bare stent and the positioning wave ring in

[0053] Figure 35 For Figure 33 Schematic diagram of another combination mode of the first bare stent and the positioning wave ring in

[0054] Figure 36 Schematic diagram of the proximal end of yet another covered stent provided in Embodiment 2 of the present invention;

[0055] Figure 37 Schematic diagram of the proximal end of another covered stent provided in Embodiment 2 of the present invention;

[0056] Figure 38 For Figure 37 Schematic diagram of the two second waveform units of the first bare wave ring along the axial positioning part being cut along the axial direction of the trough and laid flat on a plane. Detailed implementation manners

[0057] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0058] It should be noted that when an element is referred to as "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "inner", "outer", "left", "right" and similar expressions used herein are only for the purpose of illustration and do not represent the only implementation.

[0059] "Axial direction" generally refers to the length direction of a medical device when it is being delivered, and "radial direction" generally refers to the direction perpendicular to its "axial direction" of the medical device, and the "axial direction" and "radial direction" of any part of the medical device are defined based on this principle. In addition, when elaborating on a lumen stent or a covered stent, the orientation can be defined according to the blood flow direction in the blood vessel. In the present invention, it is defined that the blood flow flows from the proximal end to the distal end of the stent. A waveform unit is defined as a single-period waveform including one wave crest and two wave rods, or a single-period waveform including one wave trough and two wave rods.

[0060] In the field of interventional medical devices, generally for a delivery device that delivers a medical device when implanting the medical device into the human body or animal body, the end closer to the operator is called the "proximal end", and the end farther from the operator is called the "distal end", and the "proximal end" and "distal end" of any part of the delivery device are defined based on this principle.

[0061] Example 1

[0062] As Figures 1 - 31 shown, this example provides a covered stent 100. The covered stent 100 includes a main stent 10 and a branch stent 20, as Figure 1 shown.

[0063] As Figures 1 - 6 shown, the main stent 10 is a tubular structure with openings at both ends, including a first bare wave ring 11, a main body wave ring 12 and a main body covering film 13. The proximal part of the main body covering film 13 is its proximal end portion 131. The first bare wave ring 11 is connected to the proximal end portion of the main body covering film 13. In this example, the distal end portion of the first bare wave ring is connected to the proximal end portion of the main body covering film and shows the same inclination trend. Among them, the distal part of the first bare wave ring is its distal end portion (not shown in the figure, which can be analogized to the proximal end portion of the main body covering film). Among them, there are multiple main body wave rings 12. The multiple main body wave rings 12 are arranged axially and are connected by the tubular main body covering film 13. The number of main body wave rings 12 can be set from 1 to 30.

[0064] In this embodiment, the main wave ring 12 is disposed outside the main film covering 13. When implanted into a blood vessel, it can enhance the frictional force between the main stent 10 and the inner wall of the blood vessel, which is beneficial to preventing the main stent 10 from shifting or shortening relative to the inner wall of the blood vessel. In other embodiments, the main wave ring 12 can also be disposed inside the main film covering 13, or part of the main wave ring 12 is disposed inside the main film covering 13 and part is disposed outside the main film covering 13, which is not limited herein.

[0065] The main stent 10 includes a first side 101 and a second side 102. When the covered stent 100 is in the implanted state and the branch stent 20 faces the side of the aortic branch, the first side 101 is the side of the main stent 10 close to the aortic branch, and the second side 102 is the side of the main stent 10 away from the aortic branch. The first side and the second side each occupy an arc of 180°, and the branch stent 20 can be disposed at the middle position of the arc of the first side 101.

[0066] As Figures 3 - 4 Combined with Figure 6 And Figure 6a As shown, the distal end of the first bare wave ring 11 includes a first distal end 11a located on the first side 101 and a second distal end 11b located on the second side 102. The first distal end 11a and the second distal end 11b are located on different radial cross-sections, so that the angle between the connection line of the first distal end 11a and the second distal end 11b of the first bare wave ring 11 and the axial line of the main stent 10 is an acute angle, thereby facilitating the partial folding of the first bare wave ring 11; in this embodiment, the circumferential position of the first distal end 11a is deflected by no more than 20° relative to the circumferential position of the branch stent, and the circumferential relative interval between the second distal end 11b and the first distal end 11a is in the range of 160° to 180°. Among them, since the foldable part 111 is located on the first side 101 and the axial positioning part 112 is located on the second side 102, generally, the first distal end 11a is the distal end of the foldable part 111 and the end closest to the branch stent 20 in the circumferential direction (the end connected to the main stent), and the second distal end 11b is the distal end of the axial positioning part 112 and the end farthest from the branch stent 20 in the circumferential direction (the end connected to the main stent). In this embodiment, for the sake of description, the waveform unit is a single-period waveform including one wave crest and two wave rods (the endpoints of the two wave rods away from the wave crest are the trough positions of the waveform unit), as Figure 6 As shown, the first distal end 11a is the two symmetric trough ends of the first waveform unit 1111 in the middle of the foldable part 111, and the second distal end 11b is the two symmetric trough ends of the second waveform unit 1121 in the middle of the axial positioning part.

[0067] As Figures 1 - 6As shown, the first bare wave loop 11 includes a nitinol alloy ring composed of a plurality of waveform units in the shape of sine waves. The number of waveform units of the first bare wave loop 11 is 4 - 10; the wire diameter range of the first bare wave loop 11 is 0.3 mm to 0.45 mm; the wave height range of the waveform units is 1 mm to 15 mm. In the figure, the wave height H1 of the first waveform unit 1111 is taken as an example. H1 is as Figure 3 shown, Figure 3 The dotted line in

[0068] In this embodiment, as Figure 1 shown, the distal end portion of the second side 102 of the first bare wave loop 11 axially extends beyond the distal end portion of its first side 101, making the distal end portion of the second side of the first bare wave loop 11 closer to the distal end of the main body stent 10, so that the distal end face of the first bare wave loop 11 is in an inclined cut type. And the proximal end portion of the first side of the main body film 13 axially extends beyond the proximal end portion of the second side of the main body film, making the proximal end portion of the first side of the main body film 13 closer to the proximal end of the first bare wave loop 11, so that the proximal end face of the main body film 11 is in an inclined cut type. The proximal end face of the main body film 13 and the distal end face of the first bare wave loop 13 have the same inclination trend, which is convenient for the matching connection between the distal end portion of the first bare wave loop 11 and the proximal end portion of the main body film 11; or in other embodiments, the distal end portion of the first side of the first bare wave loop axially extends beyond the distal end portion of its second side, making the distal end portion of the first side of the first bare wave loop closer to the distal end of the main body stent, so that the distal end face of the first bare wave loop is in an inclined cut type. This is not limited herein as long as the first distal end 11a and the second distal end 11b are located in different radial cross-sections.

[0069] As Figure 5 combined with Figures 2 - 3 shown, the first bare wave loop 11 includes a first waveform unit 1111, a second waveform unit 1121, and a third waveform unit 1131. The first waveform unit 1111 is located on the first side 101, the second waveform unit 1121 is located on the second side 102, and the third waveform unit 1131 is located between the first waveform unit 1111 and the second waveform unit 1121; the axial line T1 passing through the midpoint E in the circumferential direction of the first side 101 and the axial line T2 passing through the midpoint F in the circumferential direction of the second side 102 form a projection plane S, as Figure 4 shown (in this embodiment, the branch stent is located on the axial line where the midpoint in the circumferential direction of the first side is located); the connecting line of the endpoints of the projections of the first waveform unit 1111 and the second waveform unit 1121 on the projection plane S is in a parallelogram or trapezoid shape, as Figure 3As shown, the projection plane S is the plane where the figure is located. When the distal end of the second side 102 of the first bare wave loop 11 axially extends beyond the distal end of its first side 101, the distal end of the second side 102 of the first bare wave loop 11 is made closer to the distal end of the main body bracket 10. The distal end point of the first side 101 of the parallelogram or trapezoid is closer to the distal end of the main body bracket 10 than the proximal end point of the second side 102 of the parallelogram or trapezoid. All radial cross-sections between the distal end point of the first side 101 and the proximal end point of the second side 102 can pass through the wave rods of the respective waveform units of the foldable part 111 and the axial positioning part, so that more wave rods can be intercepted in this radial cross-section, enabling the first bare wave loop 11 to still maintain a certain radial supporting effect under the inclined structure.

[0070] In this embodiment, the distal end of the second side of the first bare wave loop 11 axially extends beyond the distal end of its first side, making the distal end face of the first bare wave loop 11 in an inclined cut shape, such that the first distal end 11a of the first bare wave loop 11 is closer to the proximal end of the first bare wave loop 11 than the second distal end 11b, as Figures 1 - 3 shown. Compared with the situation where the distal end of the first side of the first bare wave loop axially extends beyond the distal end of its second side (the distal end of the first side of the first bare wave loop is closer to the distal end of the main body bracket), the setting of the first bare wave loop 11 in this embodiment, as Figure 18 combined with Figure 25 shown, makes the foldable part 111 of the first bare wave loop 11 face away from the branch bracket 20 when folded and compressed within the sheath tube 32. And because the delivery device 30 is attached to the large curvature side of the aortic arch 800 (the side with branches on the aortic arch 800), the delivery device 30 releases the first bare wave loop 11 while attached to the large curvature side of the blood vessel. When the first bare stent is partially released, only the foldable part 111 is released from the sheath tube 32. At this time, the first bare stent as a whole is the same wave loop, with a part (the foldable part 111) released from the sheath tube 32 and the other part (the axial positioning part 112) still received within the sheath tube 32, causing the proximal end of the released foldable part 111 to bend towards the lumen center of the covered stent 100; when the first bare wave loop 11 is in a natural state, the distal end of the second side of the first bare wave loop 11 axially extends beyond the distal end of its first side, making the distal end of the second side 102 of the first bare wave loop 11 closer to the distal end of the main body bracket 10 than the distal end of the first side 101; when only the foldable part 111 is released, the released foldable part 111 bends away from the large curvature side of the blood vessel towards the lumen center of the main body bracket 10. After the foldable part 111 of the first bare stent is released, the possibility of the distal end of the released foldable part 111 causing harm to the blood vessel can be reduced.

[0071] As Figure 1As shown, the proximal end of the main body membrane 13 is in an oblique incision shape. The proximal end of the first side of the main body membrane 13 axially extends beyond the proximal end of its second side, such that the proximal end of the first side 101 of the main body membrane 13 is farther from the distal end of the main body membrane 13 than the proximal end of the second side 102; alternatively, in other embodiments, the proximal end of the second side of the main body membrane axially extends beyond the proximal end of its first side. In this embodiment, the distal end face of the main body membrane 13 is in a flat mouth shape, and the proximal end of the first side 101 of the main body membrane 13 axially extends beyond the proximal end of its second side 102, that is, the proximal end of the second side 102 of the main body membrane 13 is closer to the distal end of the main body stent 10 than the proximal end of the first side 101 of the main body membrane 13. When the proximal end of the main body stent 10 is placed in the aortic arch 800, the beak effect during the fitting of the second side 102 (the side away from the branch of the arch) with the vascular arch part can be improved. In this embodiment, the valleys at the distal end of the first bare wave ring 11 are in the same plane, and the distal shape of the first bare wave ring 11 corresponds to the proximal shape of the main body membrane 13, so as to facilitate connecting the valleys of the first bare wave ring 11 with the proximal end of the main body membrane 13, as Figures 1 - 6 shown.

[0072] The first bare wave ring 11 includes a foldable part 111, a support part 113, and an axial positioning part 112. In this embodiment, the foldable part 111 is close to the first side 101, the axial positioning part 112 is close to the second side 102, and the support part 113 is connected between the foldable part 111 and the axial positioning part 112; the connection point between the foldable part 111 and one side of the support part 113 is the first connection point P. The foldable part 111 can be folded to the support part 113 with the first connection point P as the fulcrum and can be radially compressed together.

[0073] As Figure 7 shown, the foldable part 111, the support part 113, and the axial positioning part 112 in the first bare wave ring 11 are symmetrically arranged relative to the connection line T along the directions of the first side 101 and the second side 102. The direction of the connection line T is substantially consistent with the extending direction of the branch stent 20 (substantially consistent means: the included angle between the connection line T and the extending direction of the branch stent 20 is 0° to 10°). That is, from the first side 101 to the second side 102 of the first bare wave ring 11, on both sides of the connection line T, there are successively included the foldable part 111, the support part 113, and the axial positioning part 112, as Figure 7As shown, for the convenience of marking, two auxiliary dotted lines and the connecting line T are used to divide the circumferential direction of the covered stent 100 into six parts. The foldable part 111 here is symmetrically arranged relative to the connecting line T. This does not mean that the specific structures of the foldable parts 111 on both sides of the connecting line T are completely symmetric and identical, but rather that the corresponding positions on both sides of the connecting line T are the foldable parts 111; similarly, the supporting part 113 (axial positioning part 112) is symmetrically arranged relative to the connecting line T. This does not mean that the specific structures of the supporting parts 113 (axial positioning parts 112) on both sides of the connecting line T are completely symmetric and identical, but rather that the corresponding positions on both sides of the connecting line T are the supporting parts 113 (axial positioning parts 112), so as to facilitate the folding and compression of the first bare wave ring 11.

[0074] The foldable part 111 includes a first waveform unit 1111, the axial positioning part 112 includes a second waveform unit 1121, and the supporting part 113 includes a third waveform unit 1131; as Figures 2 - 3 Combined Figure 5 As shown, the third waveform unit 1131 is respectively connected to the first waveform unit 1111 and the second waveform unit 1121. The wave height of the third waveform unit 1131 is less than the wave height of the first waveform unit 1111, or / and the wave height of the third waveform unit 1131 is less than the wave height of the second waveform unit 1121. Here, the wave height refers to the vertical height from the wave peak of a waveform unit to the line connecting two wave valleys. The wave height of the third waveform unit 1131 is less than or equal to half of the smaller wave height of the first waveform unit 1111 and the second waveform unit 1121. The smaller wave height of the third waveform unit 1131 can prevent the span distance after the supporting part 113 expands from being too different from the natural span distance of the waveform when the first bare wave ring 11 is loaded into the sheath, which may cause inconvenience in folding the foldable part 111 with the film.

[0075] Define the length of the longer wave rod of the first waveform unit 1111 as L3, the length of the longer wave rod of the second waveform unit 1121 as L4, and the lumen radius of the main body stent 10 as R. Then the sum of L3 and L4 satisfies: L3 + L4 ≤ 2R; in this embodiment, the wave height, wavelength of the first waveform unit 1111 and the second waveform unit 1121 are the same, the wave height of the third waveform unit 1131 is half of the wave height of the first waveform unit 1111, and the wave valleys of the first waveform unit 1111, the second waveform unit 1121 and the third waveform unit 1131 are on the same oblique section, as Figure 3 As shown, at the same time, the proximal end of the main body covered film 13 is in an oblique incision shape, as Figure 1As shown, the inclination of the same oblique cross-section where each wave trough of the first bare wave loop 11 is located relative to the axial direction is the same as the inclination of the proximal oblique incision of the main body film 13 relative to the axial direction, which is convenient for connecting each wave trough to the proximal end of the main body film 13. The length of the longer wave rod in the first waveform unit 1111 and the third waveform unit 1131 can be set to R, so that when the film-covered stent 100 is in the loaded state, the foldable part 111 folded onto the support part 113 and the axially positioned part 112 compressed radially do not overlap axially, which can reduce the radial dimension in the compressed state and prevent interference between the axially positioned part 112 and the foldable part 111 during release.

[0076] Each wave trough of the first bare wave loop 11 is connected to the outer or inner side of the proximal end of the main body film 13, and there is no limitation here. In other embodiments, the inclination of the oblique cross-section where the distal wave trough of the first bare wave loop 11 is located may also be different from the inclination of the proximal oblique incision of the main body film 13, as long as it satisfies that the first distal end 11a and the second distal end 11b of the first bare wave loop 11 are located on different radial cross-sections, which is convenient for the foldable part 111 of the first bare wave loop 11 to fold towards the distal end onto the support part 113. In other embodiments, the proximal end of the main body film 13 does not exceed one-third of the length of the first bare stent wave rod axially, so as to facilitate that the film does not affect the folding of the first bare wave loop 11 and at the same time does not cause excessive accumulation of the film at the proximal end of the main body stent 10 after folding.

[0077] In this embodiment, the first bare wave loop 11 includes 8 waveform units, and the central angles corresponding to the arc lengths spanned by the two wave troughs of each waveform unit in the circumferential direction of the lumen of the main body stent 10 are basically the same, such as Figures 5 - 7 As shown, the foldable part 111 includes three first waveform units 1111 close to the first side 101, the axially positioned part 112 includes three second waveform units 1121 close to the second side 102, the support part 113 includes two third waveform units 1131 in the middle, and 1.5 first waveform units 1111 are located on both sides of the connection line T, 1.5 second waveform units 1121 are located on both sides of the connection line T, and one third waveform unit 1131 is located on both sides of the connection line T. When the film-covered stent 100 is loaded into the sheath, the two wave rods (1131a, 1131b) of the third waveform unit 1131 of the support part 113 open with the connection point of the two wave rods (1131a, 1131b) as the fulcrum, and the included angle between the two wave rods becomes larger and approaches 180°, which is convenient for the foldable part 111 to fold, such as Figures 17 - 18 Combined with Figure 5As shown in the figure; the first wave unit 1111 of the foldable part 111 is radially compressed, and at the same time, it folds as the third wave unit 1131 of the support part 113 expands, and it folds about 180° axially; the second wave unit 1121 of the axial positioning part 112 is radially compressed, and at the same time, it approaches the wave rod (1131b) of the adjacent support part 113. The axial positioning part 112 is only compressed radially, and the relative position in the axial direction remains basically unchanged.

[0078] As Figure 2 shown, the third wave unit 1131 includes a first wave rod 1131a and a second wave rod 1131b. The range of the included angle α between the first wave rod 1131a and the second wave rod 1131b satisfies: 46° ≤ α ≤ 145°. The included angle α between the first wave rod 1131a and the second wave rod 1131b should not be too small. If α is too small, it is not conducive to the first wave rod 1131a and the second wave rod 1131b of the third wave unit 1131 moving away from each other with the vertex of the α angle as the fulcrum, making it more difficult for the support part 113 to expand and compress into the sheath; the included angle α between the first wave rod 1131a and the second wave rod 1131b should not be too large either. If α is too large, when the first wave rod 1131a and the second wave rod 1131b move away from each other, the deformation of the support part 113 when it expands to nearly 180° (the state in the sheath tube 32) is small. When the sheath tube 32 is withdrawn to release the covered stent 100, the contribution to the elastic restoring force of the first wave rod 1131a and the second wave rod 1131b is small, which is not conducive to the covered membrane at the corresponding position of the support part 113 fitting the inner wall of the blood vessel; in other embodiments, the range of the included angle α between the first wave rod 1131a and the second wave rod 1131b that has a better effect satisfies: 77° ≤ α ≤ 89°. Define the included angle between the first wave rod 1131a and the wave rod on one side of the foldable part 111 as β. The range of the included angle β satisfies: 25° ≤ β ≤ 73°. Among them, if the β angle is too large, when the foldable part 111 is released and the support part 113 is to be released (as Figure 25 shown), it is not conducive to the support part 113 returning towards the foldable part 111 (because the deformation amount of its included angle relative to the β angle in the natural state is small). In other embodiments, the range of the included angle β satisfies: 42° ≤ β ≤ 58°; define the included angle between the second wave rod 1131b and the wave rod on one side of the axial positioning part 112 as γ. The range of the included angle γ satisfies: 52° ≤ γ ≤ 119°. Among them, if the γ angle is too small, it is not conducive to the radial return of the axial positioning part 112 (that is, Figures 25 to 26 during the process, the radial restoring force of the axial positioning part 112 is small, which is not conducive to the radial return of the axial positioning part 112 to move to the small curvature side of the aortic arch 800 and adhere to the wall). In other embodiments, the range of the included angle γ satisfies: 73° ≤ γ ≤ 87°.

[0079] As Figure 3 and Figure 6 andFigure 6a As shown, define the length of the first corrugated rod 1131a as L1, and the length of the second corrugated rod 1131b as L2. The ratio range of L1 and L2 satisfies: 2 / 3 ≤ L1 / L2 ≤ 3 / 2. If the first corrugated rod 1131a or the second corrugated rod 1131b is too long or too short, it will cause the axial position of the peak node after the support part 113 is opened. When the covered stent 100 is loaded in the sheath 32, it is not conducive to the axial distribution of the corrugated rods of the foldable part 111 and the axially positionable part.

[0080] In this embodiment, as Figure 5 shown, the connection point between the distal end of the first corrugated rod 1131a and the foldable part 111 is the first connection point P, thus forming the first trough 1131c of the support part 113. The first trough 1131c is movably connected to the main body covering film 13; the connection point between the distal end of the second corrugated rod 1131b and the axial positioning part 112 is the second connection point, thus forming the second trough 1131d of the support part 113. The second trough 1131d is movably connected to the main body covering film 13 of the stent 100. Among them, the distal end of the first bare stent is located inside the main body covering film 13. When the first bare stent is in the natural state, define the position of the first trough 1131c inside the main body covering film 13 as the first axial limit position M. As Figure 8 shown, define the position of the second trough 1131d inside the main body covering film 13 as the second axial limit position (not shown in the figure). In this embodiment, in the first bare corrugated ring 11, the troughs other than the first trough 1131c and the second trough 1131d are fixed inside the main body covering film 13. In other embodiments, the second trough 1131d can also be fixedly connected to the main body covering film 13, as long as the first trough 1131c is not fixedly connected to the main body covering film 13; it is also possible that both the first trough 1131c and the second trough 1131d are fixedly connected to the main body covering film 13, and there is a surplus or notch in a part of the main body covering film 13 between the first trough 1131c and the second trough 1131d, without restricting the first corrugated rod 1131a and the second corrugated rod 1131b from moving away from each other.

[0081] As Figures 8 - 11 shown, the main body stent 10 further includes a non-fixed limiting member 15 located at the proximal end of the first trough 1131c, which is used to limit the first trough 1131c so that the first trough 1131c does not exceed the proximal end of the covering film, thus having a supporting effect on the covering film. At the same time, during the opening process of the support part 113, the non-fixed limiting member 15 does not restrict the movement of the first trough 1131c within the limiting member, so as to facilitate the first corrugated rod 1131a and the second corrugated rod 1131b to move away from each other without involving the covering film.

[0082] In this embodiment, the non-fixed limiting member 15 is a movable limiting wire 151, and the limiting wire can be a polyester wire, a nitinol wire or a tantalum wire.

[0083] Define the wire diameter of the first bare wave loop 11 as d. The limiting wire bypasses the first wave valley 1131c and the proximal side of the main film covering 13, as Figure 8 shown, and the two ends of the limiting wire are sutured to the film covering, or one end passes through the film covering and is fixed to the other end, so that a gap Q is formed at the first axial limiting position M. The width of the gap Q extending towards the distal end from the first axial limiting position M is greater than or equal to 2d. When loading the film-covered stent 100, it is convenient for the first wave valley 1131c to slide out of the first axial limiting position M and for the first wave rod 1131a to slide within the gap Q; when releasing the film-covered stent 100, it is beneficial for the first wave rod 1131a to drive the first wave valley 1131c to return to the first axial limiting position M. The setting of the movable limiting wire 151 makes the first wave valley 1131c not exceed the proximal end of the main film covering 13, and the first bare wave loop 11 still has an expanding and supporting effect on the proximal end of the main film covering 13 corresponding to the supporting part 113 in the circumferential direction.

[0084] In other embodiments, as Figures 9 - 10 shown, the limiting wire is fixed to the main film covering 13 at at least two places (which can be the two ends of the wire), forming a first fixing point 151a and a second fixing point 151b. The first fixing point 151a is located on the proximal side of the first axial limiting position M, and the second fixing point 151b is located on the distal side of the first axial limiting position M and is spaced from the first fixing point 151a, and the width of the gap Q formed between the two fixing points is greater than or equal to 2d. Among them, the first fixing point 151a and the second fixing point 151b are on the same axial line. In other embodiments, the first fixing point 151a and the second fixing point 151b may not be on the same axial line, and the second fixing point 151b is closer to the side of the second wave valley 1131d in the vertical axial direction relative to the first fixing point 151a, so that the extending direction (the connecting line direction of the two fixing points) of the gap Q formed by the limiting wire between the first fixing point 151a and the second fixing point 151b is inclined relative to the axis, and the inclined direction is opposite to the inclined direction of the first wave rod 1131a relative to the axis, which is more beneficial for the movement of the first wave rod 1131a relative to the main film covering 13 when loading into the sheath, so that when the first wave rod 1131a and the second wave rod 1131b move away from each other, it does not affect the film covering. And when releasing the film-covered stent 100, due to the self-deformation of the supporting part 113 during loading (the included angle between the first wave rod 1131a and the second wave rod 1131b becomes larger) having a resilience force to return to the natural state, and the non-fixed limiting member 15 limits the farthest position of the proximal end of the first wave valley 1131c, the first wave valley 1131c does not exceed the proximal end of the main film covering 13, and the first bare wave loop 11 still has an expanding and supporting effect on the proximal end of the main film covering 13 corresponding to the supporting part 113 in the circumferential direction.

[0085] The proximal end of the main body stent 10 is also provided with a positioning wave coil 14. The positioning wave coil 14 is located between the first bare wave coil 11 and the main body wave coil 12. The wire diameter of the positioning wave coil 14 is smaller than that of the first bare wave coil 11, and the part of the positioning wave coil 14 located on the first side 101 is arranged on the proximal side of the branch stent 20, as Figure 12 shown.

[0086] As Figure 1 and Figure 4 combined Figure 12 shown, the branch stent 20 is located on the first side 101 of the main body stent 10, communicates with the inner part of the lumen of the main body stent 10, and extends towards the outside of the main body stent 10, forming an outer branch stent 20 on the first side 101 of the main body stent 10.

[0087] The branch stent 20 includes a second bare wave coil 21, branch wave coils 22 and a branch film 23. The second bare wave coil 21 is connected to the branch film 23, and the second bare wave coil 21 is arranged at the end of the branch stent 20 away from the main body stent 10. There are multiple branch wave coils 22, and the multiple branch wave coils 22 are arranged at intervals and are connected by a tubular branch film 23. Among them, the branch stent 20 and the main body stent 10 can connect the branch wave coils 22 and the main body film 13 into a whole through the branch film, and the connection method can be stitching, bonding and other methods. One end of the branch stent 20 away from the second bare wave coil 21 and the main body stent 10 form a connection part along the circumferential direction of the branch stent 20. A circumferential visualization ring or visualization points are arranged at intervals along the circumferential direction at the circumferential connection part to mark the circumferential boundary of the branch opening, so as to facilitate the identification of the position of the stent branch opening corresponding to the branch blood vessel.

[0088] In other embodiments, as Figures 13 - 15 shown, the branch stent 20 includes a connection section 24 and an extension section 25. The connection section 24 connects the extension section 25 and the main body stent 10. The outer diameter of the extension section 25 is larger than that of the connection section 24. There is also a transition section 27 between the extension section 25 and the connection section 24, and the outer diameter of the transition section 27 gradually increases from the connection section 24 to the extension section 25. A semi-restraint structure 26 is arranged on the branch stent 20, so that during the proximal release process of adjusting the main body stent 10, the branch stent 20 is in a semi-restrained state. The diameter of the restrained branch stent is 40% - 75% of the diameter of the branch stent before restraint, so that the branch stent 20 can move axially in the branch, thereby facilitating the adjustment of the fitting position between the connection between the proximal side of the branch stent 20 and the main body stent 10 and the blood vessel. When a branch small stent needs to be connected, the semi-restraint structure 26 can also not be set, and the outer diameter of the branch stent 20 can be set smaller, which is convenient for axially adjusting the position of the branch stent 20 after the sheath tube 32 is released. The outer diameter range is set between 6 mm and 20 mm, so that it does not adhere to the inner wall of the branch blood vessel after release. Finally, a branch small stent is released through the guide wire 90 to fit the inner wall of the branch blood vessel.

[0089] As shown Figure 15 in the figure, the semi-restraint structure 26 includes a restraint wire 26a circumferentially arranged around the branch wave loop 22 and a plurality of wire buckles 26c fixedly arranged on the branch wave loop 22 in the circumferential direction. A limit buckle 26b is arranged at the end of the restraint wire 26a. Correspondingly, the conveying device 30 further includes a limit rod 33. During loading, the limit rod 33 axially penetrates through the limit buckles 26b at both ends of the restraint wire 26a along the branch support 20, thereby semi-restraining the branch support 20 and making the branch support 20 in a state of incomplete circumferential release. The limit rod 33 can be a metal guide wire 90 with good elastic memory and small surface roughness, such as a nitinol wire, whose physical properties meet the requirements and have good biocompatibility with the human body. A plurality of restraint wires 26a are arranged at intervals along the axial direction of the branch support 20. The circumferential angle covered by the restraint wire 26a on the circumference of the branch support 20 in the natural state is 180°-270°, so as to control the change range of the branch support 20 from the semi-release state to the full-release state within a reasonable range; the restraint wire 26a can be a flexible wire with strong anti-tensile performance, such as a PTFE wire or a polyester suture, etc.

[0090] As shown Figure 12 in the figure, the axial distance from the proximal side connection point of the branch support 20 to the proximal end of the main body film 13 is defined as L5. Among them, L5 satisfies: 3mm≤L5≤16mm; when the proximal end face of the first bare wave loop 11 is not perpendicular to the axis of the covered stent 100, its proximal end face is an inclined plane, and the first bare wave loop is sutured to the main body film. When the foldable part is folded, the distance from the proximal side of the main body stent to the proximal side connection point of the branch support at this time is less than L5. The overall axial length of the branch support 20 along the axis of the branch support is defined as L6, and L6 satisfies: 3mm≤L6≤60mm; among them, L5 and L6 satisfy: L6>L5; the branch wave loops of the branch support can be arranged at intervals along the axis of the branch support, or can be a support wave loop structure formed by hooking and weaving. The branch wave loop only needs to meet the performance of its support wave loop, and its specific structure is not limited here. When the guide wire 90 is selected into the branch on the arch, the sheath core assembly 31 needs to penetrate from the distal end of the main body stent 10 and pass through the branch support 20, so as to facilitate the branch support 20 to be sent into the branch along the guide wire 90. Setting L6>L5 makes the foldable part of the first bare wave loop of the covered stent fold to the support part, the wave rods of the support part open, and together with the axial positioning part, they are compressed in the sheath tube to form a stent system. During the release process of the stent system, it is convenient for the proximal part of the branch support to be exposed from the end of the sheath tube far away from the operating handle before the proximal part of the main body stent, so as to facilitate adjusting the proximal end of the main body stent 10 in the main cavity of the arch and prevent the proximal end of the main body stent 10 from being released in the branch on the arch before the branch support 20.

[0091] In this embodiment, a first developer 16 is provided at a position on the first side of the main body film 13 where it is connected to the foldable part 111 and closest to the axial line T1 at the midpoint E in the circumferential direction of the first side 101, for identifying the proximal end of the main body stent 10 after the foldable part 111 is folded. The first developer 16 can be a developer wire sutured to the main body film 13, and can be in the shape of an 8 or a 0. The film-covered stent 100 further includes a second developer 17, which is located at the proximal end of the foldable part 111 and can be used to indicate the specific position of the end of the foldable part 111 after it is folded and compressed into the sheath 32 (when the sheath 32 passes over the end position, the foldable part 111 is released from the sheath 32). The second developer 17 can be a developer wire wound around the proximal wave crest of the first corrugated unit 1111; alternatively, the second developer may not be provided at the proximal end of the foldable part. The wire diameter of the first bare wave loop is made larger than that of the positioning wave loop 14, and the contour of the foldable part can also be made clearly visible under fluoroscopy, different from the contour of the positioning wave loop, so that the position of the foldable part in the sheath can be directly distinguished in the folded state.

[0092] This embodiment also provides a stent system, as Figures 16 - 28 shown. The stent system includes a delivery device 30 and the film-covered stent 100 as described above. The delivery device 30 includes a sheath core assembly 31 and a sheath 32. The sheath core assembly 31 further includes a guide head 311. The sheath core assembly 31 penetrates into the main body stent 10 from the distal end and exits from the branch stent 20. A part of the first bare wave loop 11 is folded and loaded into the sheath 32 as a whole. A third developer 321 is provided at the proximal port of the sheath 32, for indicating the position of the sheath 32 relative to the film-covered stent 100 during the retraction process of the sheath 32 when the film-covered stent 100 is released.

[0093] The process of loading the above film-covered stent 100 into the sheath 32 is as follows:

[0094] First, the sheath core assembly 31 is penetrated into the main body stent 10 from the distal end and exits from the port on the side of the branch stent 20 away from the main body stent 10, and the second bare wave loop 21 of the branch stent 20 is hooked on the distal end of the sheath core assembly 31, so that a releasable hooking connection is formed between the sheath core assembly 31 and the second bare wave loop 21; since the branch stent 20 and the main body stent 10 are arranged at a certain angle in the natural expansion state, the angle range can be 60° to 90°. When the sheath core assembly 31 exits from the side of the branch stent 20 away from the main body stent 10, the branch stent 20 bends toward the proximal end of the main body stent 10 and adheres to the proximal end of the main body stent 10, as Figure 16 shown;

[0095] Then, the distal portion of the main body stent 10 is gradually loaded into the sheath 32. When loading reaches the proximal end of the main body stent 10, the distal end of the axially positionable portion of the sheath 32 is constricted. Then, with the first connection point P as the fulcrum, the foldable portion 111 of the first bare coil 11 is folded towards the distal end of the main body stent 10 and approaches the first wave rod 1131a. The foldable portion 111 is axially folded by 180°; meanwhile, with the help of an external force, the third waveform unit 1131 of the support portion 113 is opened, so that the included angle between the first wave rod 1131a and the second wave rod 1131b becomes larger (tends to 180°). With radial compression, the axial positioning portion 112 approaches the second wave rod 1131b, causing the axial positioning portion 112 to be radially compressed within the sheath 32, as Figures 17 - 18 shown;

[0096] Finally, the partially folded and overall compressed first bare coil 11 is constricted within the sheath 32. The sheath 32 is further advanced to constrict the branch stent 20 within the sheath 32 until the distal end of the sheath 32 is constricted to the proximal end of the guide head 311, and the loading is completed to form a stent system, as Figures 19 - 20 shown. As Figure 20 shown, in this stent system, the free end 111a of the foldable portion 111 that is not connected to the membrane does not interfere with the proximal end of the axial positioning portion 112 (i.e., they approach each other but do not touch), or the free end of the foldable portion presses against the outside of the axial positioning portion, so that when the first bare coil is released from the sheath, the foldable portion 111 and the axial positioning portion 112 are released in sequence, thereby preventing the axial positioning portion 112 in the stent system from pressing on the outside of the folded foldable portion, resulting in an instantaneous release of the first bare coil, causing the foldable portion to adhere to the large curvature side of the blood vessel while the first bare coil is completely released and adheres to the wall as a whole, resulting in the inability to axially adjust the position of the foldable portion adhering to the large curvature side of the blood vessel wall.

[0097] Taking the implantation of the branch stent 20 into the left subclavian branch artery 803 as an example, the process of implanting the above-loaded stent system into the aortic arch 800 of the human body is as follows:

[0098] First, the guide wire 90 is selected from the femoral artery into the left subclavian branch artery 803 to be implanted to establish a delivery channel, as Figure 21 shown, and then the branch stent 20 in the stent system is delivered along the guide wire 90 to the left subclavian branch artery 803, as Figure 22 shown.

[0099] Then, as Figures 23 - 24 shown, the position of the stent system is adjusted so that the first imaging member 16 does not enter the supra-aortic branches. When the sheath 32 is retracted until the third imaging member 321 is close to the first imaging member 16, as Figure 23As shown in the figure, the sheath tube 32 is slowly withdrawn later. Since there is a certain angle between the main body stent 10 and the branch stent 20, during the process that the third imaging element 321 is located between the first imaging element 16 and the second imaging element 17, and during the process that the third imaging element 321 moves away from the first imaging element 16 and approaches the second imaging element 17, the proximal end of the main body stent 10 gradually moves away from the branch stent 20; during this process, the sheath tube 32 is slowly released, and at the same time, the delivery device 30 is pushed forward. Due to the existence of the guide wire 90, the sheath core assembly 31 advances along the guide wire 90 towards the branch, and the exposed foldable part 111 moves away from the branch stent 20 (and the part close to the greater curvature side is the membrane part), until the membrane of the main body stent 10 exceeds the inflection point on the proximal side of the left subclavian branch artery 803, then the sheath tube 32 can be continuously withdrawn to gradually release the proximal end of the main body stent 10. As Figure 25 shown, the foldable part 111 in the main body stent 10 is preferentially released, and the foldable part 111 is turned back to the proximal side of the opening 803 of the left subclavian branch artery and tends to fit the greater curvature side of the aortic arch 800; the sheath tube 32 is continuously withdrawn step by step, as Figures 25 - 26 shown, after the support part 113 and the axial positioning part 112 are also released and return to the natural state. Due to the first half of this process, the foldable part 111 has been turned back 180° and tends to fit the greater curvature side of the aortic arch 800, while the support part 113 has not been fully released, and the first trough 1131c is in a deformed state (compared with the first bare wave loop 11 in the natural state, the β angle increases), so that the support part 113 has a restoring force towards the proximal end; and due to the deformation of the support part 113 when it is compressed (the first wave rod 1131a and the second wave rod 1131b move away from each other, making the α angle tend to 180°), as the sheath tube 32 is withdrawn, the foldable part 111 fits the greater curvature side of the aortic arch 800, and there is a restoring force for the first wave rod 1131a and the second wave rod 1131b to gradually approach each other. At the same time, it can drive the axial positioning part 112 to move towards the proximal end and be released. Therefore, while the axial positioning part 112 expands radially, it will also move towards the proximal end to fit the second side 102 of the aortic arch 800.

[0100] Finally, as Figure 27 shown, after the proximal end of the main body stent 10 is released, the sheath tube 32 is quickly withdrawn to release the entire main body stent 10 to isolate the aneurysm 810. Then, the second bare wave loop 21 is released through the post-release structure of the sheath core assembly 31, so as to completely release the branch stent 20, as Figure 28As shown in the figure; if the branch stent 20 includes a semi-restraint structure 26, before releasing the second bare wave loop 21, the limiting rod 33 can be retracted to release the main body part of the branch stent 20 so that it fits against the inner wall of the left subclavian branch artery 803; if a branch needs to be reconstructed, the same guide wire 90 can be used to release a branch small stent along the guide wire 90 in the left subclavian branch artery 803 and anchor it to the branch stent 20; if no branch reconstruction is required, the delivery device 30 and the guide wire 90 are withdrawn from the human body.

[0101] It can be understood that the guide wire 90 can also be selected into the brachiocephalic trunk branch artery 801 or the left common carotid branch artery 802, and the branch structure can be released into the brachiocephalic trunk branch artery 801 or the left common carotid branch artery 802. In other embodiments, such as Figures 29 - 31 As shown in the figure, the covered stent 100 further includes a groove structure 40 and an inner branch 41. A mesh cover 42 is provided above the groove structure 40. The groove structure 40 is arranged on the distal side of the branch structure. The inner branch 41 can be arranged at the proximal end of the groove structure 40 or at the distal end of the groove structure 40; the inner branch 41 can open towards the proximal end of the main body stent 10 or towards the distal end of the main body stent 10, which is not limited herein. The guide wire 90 can be selected into the brachiocephalic trunk branch artery 801 or the left common carotid branch artery 802, and the branch structure can be released into the brachiocephalic trunk branch artery 801 or the left common carotid branch artery 802, and then a branch small stent can be externally connected to the inner branch 41 in the groove structure 40 to the brachiocephalic trunk branch artery 801 or / and the left common carotid branch artery 802, such as Figure 31 As shown in the figure.

[0102] Compared with the prior art, the covered stent 100 provided by the present invention does not need to set a main guide wire in the main cavity blood vessel of the aortic arch. The guide wire 90 is directly selected into the branches above the arch to release the whole stent, and the anchoring part of the main body stent 10 can be successfully released to achieve the anchoring of the proximal end of the main body stent 10; and even if a branch small stent is connected again, it can be realized by using the branch guide wire 90, which reduces the operation time and reduces the operation risk.

[0103] Embodiment 2

[0104] Embodiment 2 proposes another covered stent. As Figures 32 - 38 shown in the figure, the features that are the same or can be borrowed in the covered stent of Embodiment 2 and the covered stent of Embodiment 1 will not be described in detail here. The main difference is that in the covered stent of Embodiment 2, as Figures 32 - 33As shown, the foldable part 511 includes a first corrugated unit 5111, the axial positioning part 512 includes a second corrugated unit 5121, the support part 513 includes a first inclined rod 5130, and the first inclined rod 5130 is located between the first corrugated unit 5111 and the second corrugated unit 5121. Among them, the first inclined rod 5130 can be a straight rod inclined relative to the axis or an arc rod inclined relative to the axis. In this embodiment, the first inclined rod 5130 is connected to the proximal end of the main body film, and the included angle formed by the first inclined rod 5130 inclined relative to the axis is the same as the included angle formed by the plane of the proximal inclined cut of the main body film relative to the axis, so as to facilitate the overall fixation of the first inclined rod 5130 to the inner edge of the proximal end of the main body film.

[0105] In this embodiment, when the covered stent is compressed and sheathed, the first inclined rod 5130 and the axial positioning part 512 approach each other. At the same time, the foldable part 511 folds towards the distal end with the first connection point as the fulcrum to approach the first inclined rod 5130, so as to compress the first bare corrugated ring into the sheath. The setting of the first inclined rod 5130 facilitates adjusting the length occupied by the support part along the axis when it is expanded, so as to coordinate the folding of the foldable part and the compression state of the first bare corrugated ring when it is radially compressed into the sheath.

[0106] As Figures 33 - 34 shown, the main body stent further includes a positioning corrugated ring 54. The positioning corrugated ring 54 includes a second inclined rod 541. The first inclined rod 5130 and the second inclined rod 541 are connected by a steel sleeve 60 to fix the first bare corrugated ring and the fixed corrugated ring. In this embodiment, the first bare corrugated ring is a circumferentially integral corrugated ring, and the positioning corrugated ring 54 is a half corrugated ring. And both ends of the positioning corrugated ring 54 each include a second inclined rod 541 to be fixed to the first bare corrugated ring. Among them, the first bare corrugated ring being a circumferentially integral corrugated ring can make the recovery reliability of the first bare corrugated ring after deformation high, as Figure 34 shown. In other embodiments, as Figure 35 shown, the positioning corrugated ring 54 and the axial positioning part 512 are a circumferentially integral corrugated ring, the foldable part 511 and the support part 513 form a half corrugated ring, and both ends of the half corrugated ring each include a first inclined rod 5130 to be fixed to the positioning corrugated ring 54. Among them, the positioning corrugated ring 54 and the axial positioning part 512 being a circumferentially integral corrugated ring make the overall support of the proximal end of the main body stent better and the force more uniform.

[0107] In other embodiments, as Figure 35As shown, the support portion 513 may further include a third corrugated unit 5131. The first diagonal rod 5130 is connected to the third corrugated unit 5131. Both the first diagonal rod 5130 and the third corrugated unit 5131 are located between the first corrugated unit 5111 and the second corrugated unit 5121, and the third corrugated unit 5131 is located between the first corrugated unit 5111 and the first diagonal rod 5130. The support portion 513 includes the third corrugated unit 5131 and the first diagonal rod 5130, which can enable the length occupied by the support portion 513 in the axial direction when the covered stent is compressed in the sheath tube not to be limited by the wave height of the third corrugated unit 5131, facilitating the covered stent to be compressed in the sheath tube. When the support portion 513 is compressed, the axial distance is such that when the first bare wave loop is released, the recovery process is slow, reducing the possibility that the foldable portion 511 and the axial positioning portion 512 suddenly return to their original shapes and damage the inner wall of the blood vessel.

[0108] In other embodiments, the first bare wave loop includes 8 corrugated units, and the central angles corresponding to the arc lengths spanned by the two wave troughs of each corrugated unit among the 8 corrugated units in the circumferential direction of the main body stent lumen are substantially the same. As Figure 36 shown, the difference from the first bare wave loop in Embodiment 1 is that a support ring 5132 is provided at the wave crest of the support portion 513. The support ring 5132 can be formed by winding one more loop at the connection of the wave crest during the formation of the wave loop, which can increase the restoring force when the support portion 513 expands naturally and returns to the natural state. Figures 1 - 3 and Figures 5 - 7 In other embodiments, as

[0109] shown, the support portion 513 may include four (two on each side) third corrugated units 5131 in the middle, and two third corrugated units 5131 are located on both sides of the connection line T. The specific number of corrugated units included in the support portion is not limited here. When the support portion 513 includes more corrugated units, the arc length spanned by a single third corrugated unit 5131 can be appropriately reduced so that the arc length spanned by the support portion 513 in the circumferential direction as a whole is appropriate, for the purpose of facilitating the foldable portion 511 to fold and then be radially compressed together with the expanded support portion 513, the arc length spanned by the support portion as a whole in the circumferential direction is set. Among them, a support ring 5132 is provided at the connection of the wave troughs between the two third corrugated units on the same side. The support ring 5132 can be formed by winding one more loop at the connection of the wave trough during the formation of the wave loop to increase the restoring force between the two connected first corrugated units 5131. In addition, support rings can also be provided at the wave crests of these two third corrugated units to increase the restoring force of the support portion as a whole. The number of support rings provided is not limited, and only needs to be provided at the wave crests or wave troughs of the first bare wave loop. Figures 37 - 38 As

[0110] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0111] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. An aortic covered stent, characterized in that, The covered stent includes a main stent and a branch stent. The main stent includes a first side and a second side. The branch stent is located on the first side. The main stent includes a first bare wave ring, a main wave ring, and a main covering film. The main covering film is disposed on the main wave ring. The proximal end of the first bare wave ring is connected to the main covering film. The distal end of the first bare wave ring includes a first distal end located on the first side and a second distal end located on the second side. The first distal end and the second distal end are located on different radial cross-sections.

2. The aortic covered stent according to claim 1, wherein The proximal end of the main covering film is in an inclined cut shape.

3. The aortic covered stent according to claim 2, wherein The distal end of the second side of the first bare wave ring axially extends beyond the distal end of its first side, such that the distal end face of the first bare wave ring is in an inclined cut shape.

4. The aortic covered stent according to claim 1, wherein, The first bare wave ring circumferentially includes a foldable portion, a support portion, and an axial positioning portion; the foldable portion is close to the first side, the axial positioning portion is close to the second side, and the support portion is connected between the foldable portion and the axial positioning portion; the foldable portion includes a first waveform unit; the axial positioning portion includes a second waveform unit; the support portion includes a third waveform unit; the third waveform unit is respectively connected to the first waveform unit and the second waveform unit, and the wave height of the third waveform unit is less than the wave height of the first waveform unit, or / and the wave height of the third waveform unit is less than the wave height of the second waveform unit.

5. The aortic covered stent according to claim 4, wherein, The third waveform unit includes a first wave rod and a second wave rod, and the range of the included angle α between the first wave rod and the second wave rod satisfies: 46° ≤ α ≤ 145°.

6. The aortic covered stent according to claim 1, wherein The first bare wave ring circumferentially includes a foldable portion, a support portion, and an axial positioning portion; the foldable portion is close to the first side, the axial positioning portion is close to the second side, and the support portion is connected between the foldable portion and the axial positioning portion; the foldable portion includes a first waveform unit; the axial positioning portion includes a second waveform unit; the support portion includes a first inclined rod, and the first inclined rod is located between the first waveform unit and the second waveform unit.

7. The aortic covered stent according to claim 6, characterized in that The support portion further includes a third waveform unit, the first inclined rod is connected to the third waveform unit, and both the first inclined rod and the third waveform unit are located between the first waveform unit and the second waveform unit.

8. The aortic covered stent according to claim 1, wherein The first bare wave ring circumferentially includes a foldable portion, a support portion, and an axial positioning portion; the foldable portion is close to the first side, the axial positioning portion is close to the second side, and the support portion is connected between the foldable portion and the axial positioning portion; the connection point between the foldable portion and the support portion is a first connection point, the first connection point is a first wave valley, and the first wave valley is movably connected to the main covering film, facilitating the relative sliding of the first wave valley with respect to the main covering film without exceeding the proximal end of the main covering film.

9. The aortic covered stent according to claim 1, characterized in that, The distal end portion of the distal end of the second side of the first bare wave loop axially extends beyond the distal end portion of its first side; the first bare wave loop includes a first waveform unit, a second waveform unit, and a third waveform unit, the first waveform unit is close to the first side, the second waveform unit is close to the second side, and the third waveform unit is located between the first waveform unit and the second waveform unit; an axial line passing through the midpoint of the first side and an axial line passing through the midpoint of the second side form a projection plane, and the projections of the first waveform unit and the second waveform unit on the projection plane are in the shape of a parallelogram or a trapezoid.

10. A support system, characterized in that, The stent system includes a delivery device and a covered stent according to any one of claims 1-9. The delivery device includes a sheath core assembly and a sheath tube. The sheath core assembly penetrates into the distal end of the main stent and exits from the branch stent. The first bare wave loop is partially folded and loaded into the sheath tube as a whole.

11. The stent system according to claim 11, wherein, The delivery device further includes a guide head. Define the axial distance from the proximal side connection point of the branch stent to the proximal end of the main covered membrane as L5, and define the overall axial length of the branch stent as L6. Among them, L5 and L6 satisfy: L6 > L5. In the stent system, the branch stent is closer to the guide head axially than the proximal end of the main stent.

12. The stent system according to claim 11, wherein, The free end of the foldable portion and the proximal end portion of the axial positioning portion do not interfere with each other, or the free end of the foldable portion presses on the outside of the axial positioning portion.

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