Lumen stent and lumen stent system

Abstract

This invention provides a luminal stent. During delivery, the luminal stent includes a covered stent and a bare stent connected proximally to the covered stent. The bare stent and the covered stent are flipped together so that after the bare stent is released from the delivery device, it flips back into the covered stent. This luminal stent, through the flipping connection between the bare stent and the covered stent, prevents interference with vascular branches after complete release of the bare stent. Specifically, it avoids the bare stent blocking the entrance to the branch artery, thus preventing blood supply disruption; it also prevents the bare stent from pressing against the interior of the branch vessel, thus avoiding branch vessel dissection.

Description

Technical Field

[0001] This invention relates to the field of interventional medical device technology, and in particular to a lumen stent and a lumen stent system. Background Technology

[0002] Aortic aneurysm is a common aortic disease. The main existing treatments for aortic aneurysms include traditional open surgery and endovascular repair. Endovascular repair is widely used due to its advantages such as minimal trauma, short operation and hospitalization time, rapid postoperative recovery, and low complication rate. The surgical principle is to compress a covered stent and pre-load it into the sheath of a delivery device. The delivery device sheath is then delivered to the lesion site in the blood vessel, and the stent is released from the delivery device sheath. The stent unfolds and adheres to the blood vessel through its own radial support force. The covered stent isolates the healthy blood vessel from the aneurysm, thus curing the aneurysm.

[0003] During endovascular repair, the luminal stent 50 has a post-release structure to ensure stable deployment, such as... Figure 1 As shown, the post-release structure refers to the hook structure 71 at the front end of the delivery device, and the exposed corrugated coil (bare stent corrugated coil 51) at the proximal end of the stent 50. The bare stent corrugated coil 51 can be hooked onto the hook structure 71 for post-release. When the stent 50 is delivered to the release position using the delivery device, the sheath is withdrawn, and the stent 50 unfolds and adheres to the blood vessel. Because the front end of the stent 50 is fixed to the hook structure 71 by the bare stent corrugated coil 51, the stent 50 will not shift during the deployment of the covered stent. Then, the hook structure 71 of the delivery device is opened, the bare stent corrugated coil 51 detaches from the hook structure 71 and fully unfolds, and the delivery device system is withdrawn. The release effect is as follows: Figure 2 As shown, for some special locations of the aorta, the aorta has branch vessels 53, such as the coronary arteries at the ascending aorta, the upper limb arteries at the aortic arch, and the visceral and renal arteries of the abdominal aorta. When the aneurysm 54 expands close to the branch vessel 53, and the aneurysm neck (the length of the proximal anchorage of the stent 50) is short, the proximal end of the stent 50 needs to be as close as possible to the branch vessel 53 to obtain more anchorage length. At this time, the bare stent coil 51 may block the entrance of the branch vessel 53, affecting blood supply. In more serious cases, the bare stent coil 51 may push against the interior of the branch vessel 53, causing the branch vessel 53 to dissect. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the problem in the prior art where the bare stent coil obstructs the branch artery entrance after the release of the luminal stent for aortic aneurysm, thereby affecting blood supply, or even the bare stent coil reaching into the branch vessel, thereby causing branch vessel dissection. The present invention provides a luminal stent and a luminal stent system.

[0005] The technical solution adopted by this invention to solve its technical problem is:

[0006] One embodiment of the present invention provides a lumen stent. During the delivery process, the lumen stent includes a covered stent and a bare stent connected to the proximal end of the covered stent. The bare stent and the covered stent are flipped together so that after the bare stent is released from the delivery device, the bare stent flips into the covered stent.

[0007] In one embodiment of the present invention, when the lumen stent is delivered, the bare stent is in a compressed state, and the process of the bare stent flipping from the compressed state into the covered stent includes a compressed state, a first release state, a post-release state, and a natural state in sequence.

[0008] In one embodiment of the present invention, the bare support includes a first corrugated ring connected to the covered support. The covered support includes a main support and a covering film on the main support. The main support includes a plurality of corrugated rings arranged at intervals along the axial direction. The corrugated ring closest to the bare support is a second corrugated ring. When the bare support and the covered support are in the unfolded state of the flip connection, the first corrugated ring and the second corrugated ring are arranged at intervals along the axial direction.

[0009] In one embodiment of the present invention, the covered stent is a hollow tube in its natural state. The radius of the tube of the covered stent is defined as R, and the wave height of the first wave ring is defined as H. Then H satisfies: H≤R.

[0010] In one embodiment of the present invention, the axial distance D between the trough of the first wave loop and the crest of the second wave loop satisfies: 0mm < D ≤ 3mm.

[0011] In one embodiment of the present invention, the trough of the first wave loop and the peak of the second wave loop are connected by polymer lines.

[0012] In one embodiment of the present invention, the trough of the first wave loop and the crest of the second wave loop are not on the same straight line along the axial direction.

[0013] In one embodiment of the present invention, the trough of the first wave loop and the trough of the second wave loop are on the same straight line along the axial direction.

[0014] In one embodiment of the present invention, each single wave of the first wavering is at the same height, and the wave height of the first wavering is the same as that of the second wavering.

[0015] In one embodiment of the present invention, the first wave loop and the second wave loop have the same wave period.

[0016] In one embodiment of the present invention, the process of the bare stent from the first released state to the natural state includes passive flipping or automatic flipping.

[0017] The aforementioned luminal stent uses a flip-over connection between the bare stent and the covered stent to allow the bare stent to flip back into the covered stent after being released from the delivery device. This prevents the bare stent from interfering with the vascular branches after complete release, thus avoiding the bare stent blocking the entrance of the branch artery and thus avoiding affecting blood supply. It also prevents the bare stent from pressing against the inside of the branch vessel, thus avoiding branch vessel dissection.

[0018] The present invention also provides another lumen stent system, including a delivery device and the above-described lumen stent, the delivery device including a sheath and a sheath core assembly, wherein a receiving cavity for receiving the lumen stent is formed between the sheath and the sheath core assembly. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0020] Figure 1 This is a schematic diagram of the structure of a lumen stent in the post-release state in the prior art;

[0021] Figure 2 This is a schematic diagram of the structure of a lumen stent in the fully released state in the prior art;

[0022] Figure 3 This is a schematic diagram of a regular octagonal ring structure in its natural state.

[0023] Figure 4 yes Figure 3 A schematic diagram of the flipped regular octagonal ring structure;

[0024] Figure 5 A schematic diagram of the structure of a wave-shaped ring in its natural state;

[0025] Figure 6 This is a schematic diagram of the lumen support in its natural state according to an embodiment of the present invention;

[0026] Figure 7 This is a schematic diagram of the structure of the bare stent and the covered stent being flipped and connected in one embodiment of the present invention;

[0027] Figure 8 This is a schematic diagram of the structure of the bare support when it is flipped back to 90° in one embodiment of the present invention;

[0028] Figure 9 This is a schematic diagram of a bare support in a compressed state according to an embodiment of the present invention;

[0029] Figure 10 This is a schematic diagram of the bare stent in the first released state according to an embodiment of the present invention;

[0030] Figure 11 This is a schematic diagram of the bare stent in the post-release state according to an embodiment of the present invention;

[0031] Figure 12 This is a schematic diagram of the bare stent in its natural state when fully released, according to one embodiment of the present invention;

[0032] Figure 13 This is a schematic diagram of the lumen support in its natural state according to an embodiment of the present invention;

[0033] Figure 14 This is a schematic diagram of the structure of the lumen support in its natural state according to another embodiment of the present invention;

[0034] Figure 15 This is a schematic diagram of the structure of the bare scaffold and the covered scaffold being flipped and connected in another embodiment of the present invention;

[0035] Figure 16 This is a schematic diagram of the bare stent in the post-release state in another embodiment of the present invention;

[0036] Figure 17 This is a schematic diagram of the bare stent in its natural state when fully released, according to another embodiment of the present invention;

[0037] Figure 18 This is a schematic diagram of the structure of the flipped wave and the fixed wave flipped and connected in another embodiment of the present invention;

[0038] Figure 19 This is a schematic diagram of the structure in another embodiment of the present invention, showing the flip wave in the post-release state;

[0039] Figure 20 This is a schematic diagram of the structure of the bent wave in its natural state in another embodiment of the present invention;

[0040] Figure 21 This is a schematic diagram of the structure of the bent wave in a post-release state in another embodiment of the present invention. Detailed Implementation

[0041] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0042] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening 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 intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0044] For ease of description, a blood vessel is used as an example to illustrate the lumen. This blood vessel can be the aortic arch, the thoracic aorta, or the abdominal aorta, etc. Those skilled in the art should understand that the use of a blood vessel is merely illustrative and not intended to limit the invention. The solutions of this invention are applicable to various human lumens, such as the digestive tract lumens, and various modifications and variations based on the teachings of this invention are within the protection scope of this invention. Furthermore, in describing blood vessels, orientation can be defined according to the direction of blood flow; in this invention, blood flow is defined as flowing from the proximal end to the distal end.

[0045] In this application, "film-coated stent" refers to a structure with a film covering the surface of a bare stent. A bare stent refers to a structure including at least one uncoated waveform. Bare stents are generally used as hook structures to be hooked onto the conveyor during post-release.

[0046] To facilitate understanding of the technical solution of this invention, the terms "flip connection," "passive flip," and "automatic flip" are explained below:

[0047] Flip-over connection: This refers to connecting a ring-shaped or cylindrical structure (made of elastic material) to other structures (e.g., tubular structures) by flipping its inner surface outwards from its natural state, or connecting it to other structures (e.g., tubular structures) with the non-connecting end flipping over using the connecting end as a fulcrum. Alternatively, it can refer to a corrugated ring structure where part of a single wave is fixed, while another part (flipped wave) flips relative to the fixed wave. In this case, the corrugated ring structure has a torsional force within it, causing the flipped wave to return to its natural state relative to the fixed wave. Another possibility is a non-ring-shaped elastic material pre-bent at a certain point, including a fixed part and a flipped part. Under external force, the flipped part can unfold relative to the fixed part. After the external force is removed, the flipped part tends to return to its pre-bent natural state using that point as a fulcrum. The unfolded state under external force represents the flip-over connection between the flipped and fixed parts of the structure.

[0048] Taking a wave-shaped ring as an example, if the entire structure is completely rotated 180°, it can reach a substable state where the inner and outer surfaces are interchanged (the initial inner surface rotated 180° to become the outer surface, and the initial outer surface became the inner surface). If, under the action of an external force, the rotation angle of the non-fixed elastic body is within the range of (0°, 180°), then due to the elasticity of the elastic body itself and the torque caused by the rotation, the wave-shaped ring tends to move from the rotation state to a stable or substable state when the external force is removed. If a part of the wave in the wave-shaped ring is fixed in its natural state, and under the action of an external force, another part of the wave is rotated (0°, 180°), when the external force is removed, the rotated part of the wave in the wave-shaped ring tends to return to its natural state.

[0049] Passive flipping: refers to an unstable state in which a ring or cylindrical structure is flipped to the range of (90°, 180°). When the external force is removed, the ring or cylindrical structure tends to move from the unstable state to a substable state. It is necessary to use external force to bring the partially flipped structure to an unstable state within the range of (0°, 90°) before removing the external force. Then, the ring or cylindrical structure tends to flip back to its natural state.

[0050] Active flipping: refers to a ring-shaped, wave-shaped, or cylindrical structure being in an unstable state within the range of (0°, 180°). When the external force is directly removed, the ring-shaped or cylindrical structure tends to flip back to its natural state from this unstable state. For example, if part of the wave in a wave-shaped ring is fixed in its natural state, and another part of the wave is flipped (0°, 180°) under the action of an external force, the flipped part of the wave can return to its natural state when the external force is removed; or when there are other elastic forces that can cause the wave-shaped ring to flip back to its natural state from the flipped state.

[0051] The principle behind the ability of ring-shaped or cylindrical structures to automatically revert to their natural state is explained briefly below:

[0052] Please see Figure 3 Taking a regular octagonal ring structure 60 (made of elastic material) as an example to illustrate the principle, the ring structure 60 made of elastic material includes an inner surface 61 and an outer surface 62. The ring structure 60 has an interior angle θ1 in its natural state. Taking one end (the axial end) of the ring structure 60 as a fulcrum, a torque is applied to the other end of the ring structure 60, causing the ring structure 60 to rotate... Figure 3 The arrow shown points outwards in the direction W, with the outward angle ranging from 0° to 180°.

[0053] When the annular structure 60 is completely rotated 180° under the action of torque, a sub-stable state is achieved where the inner surface 61 and the outer surface 62 are interchanged (the inner surface 61 in its natural state is rotated 180° to become the outer surface 62, the inner angle θ1 in its natural state is turned outward to become θ2, and the outer surface 62 in its natural state becomes the inner surface 61). Figure 4 As shown. Since the flipping of the ring structure 60 is essentially due to the elastic deformation of the elastic body, the elastic body of the ring structure 60 in the substable state can easily flip back to the natural state under a very small torque force; conversely, a larger torque is required for the elastic body of the ring structure 60 to undergo elastic deformation from the natural state to the unstable state.

[0054] For the waveform ring-shaped material 80 commonly used in vascular stents, such as Figure 5 The wave-shaped ring 80 shown includes crests 81 and troughs 82. Because it is made of an elastic material, the wave-shaped ring 80, in its natural state, will change direction under the action of an applied torque. Figure 5 The peak 81 is the fulcrum. Figure 5 The trough 82 shown in the diagram flips inward or outward around the crest 81, undergoing elastic deformation. When the non-fixed wave-shaped ring 80 flips from its natural state (0°, 180°) to an unstable flipping state, it tends to flip back due to the elasticity of the wave-shaped ring 80 itself and the resisting torque caused by the flipping. When the applied torque is removed, the wave-shaped ring 80 tends to move from the flipping state to a stable or substable state.

[0055] Specifically, if the wave-shaped ring 80 is in an unstable state within the range of (0°, 90°) under the action of an external force (torque), when the external force is removed, the wave-shaped ring 80 tends to flip back to its natural state from this unstable state; if the wave-shaped ring 80 is in an unstable state within the range of (90°, 180°) under the action of an external force (torque), when the external force is removed, the wave-shaped ring 80 tends to flip back to its sub-stable state from this unstable state. If a small external force can be applied to bring the partially flipped structure to an unstable state within the range of (0°, 90°) and then the external force is removed, then the wave-shaped ring 80 tends to flip back to its natural state.

[0056] If a portion of the wave in the waveform ring 80 is fixed in its natural state, and another portion of the wave is flipped (0°, 180°) under the action of an external force (torque), since a portion of the wave is fixed, and the other portion of the wave that is flipped by the waveform ring 80 is affected by its own elastic deformation and the resistance torque generated by the wave ring itself, then when the external force interference is removed, the flipped portion of the wave has a tendency to return to its natural state from the flipped state.

[0057] Example 1

[0058] like Figure 6-11 As shown, the luminal stent system 100 provided in this embodiment includes a luminal stent 10 and a delivery device 70. The luminal stent 10 is delivered to the implantation site (e.g., the aortic arch near the upper limb artery) via the delivery device 70. Figure 9-11 As shown.

[0059] During the transportation process, such as Figure 6-7 Combination Figure 9-11 As shown, the lumen stent 10 includes a covered stent 12 and a bare stent 11 connected to the proximal end of the covered stent 12. The covered stent 12 includes a main stent 121 and a covering 122 covering the main stent 121. The main stent 121 supports the covering 122 to form a hollow tubular structure. The main stent 121 includes a plurality of annular Z-shaped corrugations arranged axially at intervals. Each corrugation is made of a metallic elastic material (e.g., nickel-titanium alloy) to facilitate the placement of the lumen stent 10 (using a covered stent 121, a bare stent 122, and a bare stent 11 connected to the proximal end of the covered stent 121). Figure 7 When the lumen stent 10 is compressed radially (as shown) into the sheath 73 of the delivery device 70, radial deformation can occur, allowing the delivery device 70 to load the lumen stent 10. Simultaneously, after the delivery device 70 delivers it to the implantation site for initial release, the covered stent 12 can unfold in the blood vessel, and then the bare stent 11 is subsequently released using the hook structure 71 of the delivery device 70. Because the bare stent 11 and the covered stent 12 of the lumen stent 10 provided in this embodiment are connected in a flip-over manner during delivery, after the delivery device 70 performs the subsequent release of the bare stent 11, the bare stent 11 will flip back into the covered stent 12, as shown. Figure 6 Combination Figure 9-12 As shown. The membrane 122 is made of PTFE or PET membrane and is used to isolate blood flow.

[0060] The bare stent 11 includes a first corrugated coil 111, one end of which is connected to but not fixed to the coated stent 12. In this embodiment, the bare stent and the coated stent are movably connected by a coating and polymer threads, allowing the bare stent 11 to be flipped relative to the coated stent, and the first corrugated coil 111 is as follows: Figure 5 The waveform ring shown. In other embodiments, the first wave ring may also include a reversible single wave or a single wave with a reversible portion, as long as the first wave ring and the covered stent can be reversibly connected (or the reversible portion of the first wave ring and the fixing portion can be reversibly connected) so that the bare stent can be reversibly returned to the covered stent after being released from the conveyor 70. The main stent 121 includes a plurality of annular Z-shaped wave rings arranged at intervals along the axial direction, and the wave ring of the main stent 121 closest to the first wave ring 111 is the second wave ring 1211. The lumen stent 10 is in its natural state as follows: Figure 6As shown (in this embodiment, the bare stent 11 in its natural state is attached to the membrane 122, and the angle between the bare stent 11 and the bare stent in its natural state is 0°), both the first corrugated coil 111 and the second corrugated coil 1211 are located in the region near the proximal end of the lumen stent 10. The difference is that one end of the first corrugated coil 111 (e.g., ...) Figure 7 The proximal end of the first corrugated ring 111 (in the flipped state shown) is connected to the covering 122. Other parts of the first corrugated ring 111 are attached to the covering 122 in their natural state but are not connected to it. This facilitates the rotation of the lumen stent 10 into the form of the covered stent 12 with the first corrugated ring 111 flipped (i.e., when the bare stent 11 and the covered stent 12 are in the unfolded state of flipped connection, such as...). Figure 7 As shown, the bare stent 11 at this time has an angle of approximately 180 degrees with the bare stent in its natural state (approximately 180 degrees means that there can be a deviation of ±5 degrees). It is compressed and loaded into the sheath tube 73 for transportation. The flipping fulcrum of the first wave coil 111 is the connection point between the first wave coil 111 and the covering film. The second wave coil 1211 belongs to the main stent 121 and is attached to the covering film 122 by the two layers of covering film to support the covering film 122.

[0061] like Figure 7 As shown, when the bare support 11 and the coated support 12 are in an unfolded state of flip-connection but not compressed, the first wave coil 111 and the second wave coil 1211 are spaced apart axially. The axial distance D between the trough of the first wave coil 111 and the crest of the second wave coil 1211 satisfies: 0mm < D ≤ 3mm. In other embodiments, D satisfies: 1mm ≤ D ≤ 3mm, leaving a gap between the first wave coil 111 and the second wave coil 1211. Because the gap is connected by the soft coating 122, and the first wave coil 111 and the coated support 12 are flip-connected and compressed into the sheath 73 of the conveyor 70, combined with... Figure 9 As shown, when the post-release structure of the conveyor 70 releases the first wave coil 111 in the post-release state, the soft membrane 122 facilitates the free rotation of the first wave coil 111 towards the cavity of the membrane support 12, as... Figure 6 Combination Figure 9-11 As shown, this is to prevent the first wave coil 111 and the second wave coil 1211 from interfering with each other axially in the upward direction, which would make it difficult to flip.

[0062] In this embodiment, the covered stent 12 is a hollow tube in its natural state, such as... Figure 7-8As shown, the tube radius of the covered support 12 is defined as R, and the wave height of the first wave ring 111 is defined as H. Then H satisfies: H≤R. This can prevent the wave heights from interfering with each other and causing the reversal failure during the process of the first wave ring 111 flipping back into the covered support 12 (in its natural state). After the stent is flipped back into the covered stent 12, it will closely adhere to the proximal covered segment of the covered stent 12, allowing the proximal covered segment to better fit the blood vessel and reduce type I endoleak. To achieve the best effect in reducing type I endoleak, the first wave 111 and the second wave 1211 have the same wave height and wave period. The troughs of the first wave 111 and the second wave 1211 are on the same straight line along the axial direction. This facilitates the intersecting of the wave rods of the first wave 111 and the second wave 1211 after the first wave 111 is flipped. The first wave 111 can support the covered segment 122 (the covered segment not supported by the second wave 1211) in the gaps of the second wave 1211, thereby making the covered segment 122 at the proximal end of the stent 10 better fit the blood vessel. The double-layered intersecting wave structure provides a better sealing effect after the covered segment 122 at the proximal end of the stent 10 fits the blood vessel, reducing endoleak and stent displacement. Figure 6 and Figure 12 As shown. Meanwhile, during the compression loading of the lumen support 10 into the sheath 73, the first wave coil 111 is in a non-natural, flipped connection state (e.g., Figure 7 and Figure 9 As shown), the area where the second wave ring 1211 is located will not increase its compression area. Therefore, after the lumen stent 10 provided in this embodiment is fully released, the first wave ring 111 (in this embodiment, the annular wave ring of the bare stent 11) will flip back into the covered stent 12 (the lumen stent 10 is in its natural state, such as...). Figure 6 As shown, this design prevents interference with vascular branches after the bare stent 11 is fully deployed. This avoids the bare stent 11 blocking the entrance to the branch artery, thus preventing impaired blood supply; it also prevents the bare stent 11 coil from pressing against the inside of the branch vessel, thus preventing branch vessel dissection. Without increasing the assembly volume of the stent 10, it also enhances the sealing effect at the proximal end of the stent 10, reducing endoleak and stent displacement.

[0063] In other embodiments, when the individual waves of the first wave loop 111 and the second wave loop 1211 are of equal height, and the wave heights and wave periods of the first wave loop 111 and the second wave loop 1211 are equal, the troughs of the first wave loop 111 and the crests of the second wave loop 1211 are not on the same straight line along the axial direction, such as... Figure 6 As shown, after the first wave coil 111 is flipped, the wave rod of the first wave coil 111 and the wave rod of the second wave coil 1211 can cross.

[0064] The process of flipping and connecting the bare stent 11 to the covered stent 12 includes: flipping the bare stent 11 to its natural state (e.g., ... Figure 6The bare stent 11 of the lumen stent 10 (as shown) is flipped to the position as follows: Figure 7 After reaching the state shown, it is compressed radially and then loaded into the sheath 73 of the conveyor 70, as... Figure 9 As shown, the angle between the bare stent 11 at this time and the bare stent 11 in its natural state is approximately 180°. When the lumen stent 10 is transported using the conveyor 70, both the bare stent 11 and the covered stent 12 are in a compressed state. The complete release process of the lumen stent 10 provided in this embodiment includes, in sequence: compressed state, first release state, post-release state, and natural state.

[0065] In compressed state, such as Figure 9 As shown (in combination) Figure 7 The compressed lumen support 10 is loaded into the sheath 73 of the delivery unit 70. Because the bare support 11 and the coated support 12 are connected by an inverted connection, and the crest of the first wave 111 (as shown in the image)... Figure 7 The wave crest shown is hooked onto the hook structure 71 of the conveyor 70. The hook structure 71 maintains the first wave 111 of the bare support 11 in a flipped state relative to the coated support 12. Due to the spatial constraint of the sheath 73, the lumen support 10 in the compressed state (such as...) Figure 9 (As shown) relative to the lumen stent 10 in its natural state (e.g.) Figure 6 As shown), the bare stent 11 will remain in a flipped connection with the covered stent 12. The covered stent 12 is compressed radially. After the lumen stent 10 is delivered to the implantation site in this state, the sheath 73 is withdrawn to release the covered stent 12.

[0066] like Figure 9-12 Combination Figure 6-7 As shown, the process from the compressed state to the first release state also includes retracting the sheath 73 to release the covered stent 12. This process involves retracting the sheath 73 in the opposite direction to the insertion direction (i.e., along the direction of blood flow), gradually releasing the luminal stent 10 from its proximal end to its distal end until the covered stent 12 is completely released, leaving only the bare stent 11 hooked onto the hook structure 71 of the delivery device 70. Figure 10 As shown. During the process of releasing the covered stent 12 by retracting the sheath 73, due to the backward frictional force between the sheath 73 and the covered stent 12 (in the direction of retracting the sheath 73), the first coil 111 of the bare stent 11 remains in a flipped state until the sheath 73 completely releases the covered stent 12. At this time, the bare stent 11 is still hooked on the hook structure 71, while the covered stent 12 expands and unfolds, adhering to the vessel wall and playing a certain role in fixation.

[0067] First release state: After the covered stent 12 is fully released from the sheath of the delivery device, it expands and adheres to the vessel wall (e.g., Figure 10As shown, the first wave ring 111 of the bare stent is still hooked to the hook structure 71. The expanded stent 12 has a certain fixing effect on the wall. At this time, the sheath core assembly 72 can be moved backward, thereby driving the hook structure 71 on the sheath core assembly 72 to move towards the distal end of the lumen stent 10. Under the action of the hook structure 71, the first wave ring 111 of the bare stent can be flipped inward to the inside of the covered stent 12.

[0068] Post-release state: The state in which the hook assembly disengages the first wave coil 111 is the post-release state. In this embodiment, the first wave coil 111, driven by the hook structure 71, flips to an angle less than 90° with the first wave coil 111 in its natural state (in this embodiment, the bare support 11 in its natural state is in contact with the film 122). If the first wave coil 111 is not subjected to external force at this time, it has a tendency to flip back to its natural state (e.g., Figure 11 (As shown). Opening the anchor 712 allows the first wave ring 111 to disengage from the hook structure 71. Since it has a tendency to flip back to its natural state, the first wave ring 111 will flip back to its natural state.

[0069] Natural state: After the first wave 111 detaches from the hook structure 71 and flips back into the covered stent 12, the bare stent 11 is in its natural state. Both the covered stent 12 and the bare stent 11 adhere to the vessel wall. Figure 12 As shown.

[0070] That is, the flipping of the bare support 11 in this embodiment is: passively flipping from the first release state (driven by the hook structure 71) to the later release state, then disengaging from the hook structure 71 and automatically flipping back to the natural state.

[0071] In other embodiments, since the first wave loop 111 is only partially connected to the near end of the film 122 segment of the film-covered support 12, leaving most of the first wave loop 111 exposed outside the film 122, a polymer thread 13 can be provided in the film 122 to enhance the connection strength between the first wave loop 111 and the film-covered support 12. The polymer thread 13 has its two ends connected to the first wave loop 111 and the second wave loop 1211, respectively. In one embodiment, the two film layers are bonded together, covering the main support 121. The polymer thread 13 is pressed between the two film layers 122, and one end is connected to the trough of the first wave loop 111 (referring to the trough when the first wave loop 111 and the film-covered support 12 are flipped and connected, such as...). Figure 13 As shown), the other end is connected to the peak of the second wave cycle 1211, as shown. Figure 13 As shown, the number of polymer lines 13 can be the same as the number of wave periods.

[0072] The lumen support system 100 provided in this embodiment, such as Figure 9-12As shown, the device includes a conveyor 70 and a lumen support 10 as described above. The conveyor 70 includes a sheath 73, a sheath core assembly 72, and a hook structure 71. The hook function is formed by the cooperation of a guide head 711 and an anchor 712. A receiving cavity for accommodating the lumen support 10 is formed between the sheath 73 and the sheath core assembly 72. The sheath core assembly 72 includes an inner sheath core (not shown) and an outer sheath core 721. The inner sheath core is connected to the guide head 711, and the outer sheath core 721 is connected to the anchor 712. The outer sheath core 721 can move axially relative to the inner sheath core under the control of a handle, thereby causing the anchor 712 to close or move away from the bottom of the guide head 711, thereby enabling the first wave 111 of the bare support 11 to hook or detach from the hook structure 71. Compared to existing luminal stent systems, this design prevents interference with vascular branches after the bare stent 11 is fully deployed. Specifically, it avoids the bare stent 11 blocking the entrance to the branch artery, thus preventing impaired blood supply; it also prevents the bare stent 11 coil from reaching the interior of the branch vessel 53, thus avoiding branch vessel dissection. Without increasing the assembly volume of the luminal stent 10, it also enhances the sealing effect at the proximal end of the luminal stent 10, reducing endoleaks and stent migration.

[0073] Example 2

[0074] Example 2 proposes a lumen stent 20 and a lumen stent system, such as Figure 14-17 As shown. The features of the lumen stent 20 and lumen stent system in Embodiment 2 that are the same as or can be reused from those in Embodiment 1 will not be described again here. The main difference is that the lumen stent 20 in Embodiment 2 also includes a foldable, reversible folding rod structure 23, through which the first wave coil 211 and the second wave coil 2211 are connected. The natural states of the folding rod structure 23 and the bare stent 21 are as follows... Figure 14 As shown, the folding rod structure 23 is in its natural folded state at this time. The first wave ring 211 and the second wave ring 2211 are both located in the region near the end of the lumen support 20. One end of the first wave ring 211 is connected to the membrane 222, and the other parts of the first wave ring 211 are attached to but not fixed to the membrane 222. This allows the lumen support 20 to be flipped out of the membrane support 22 shape with the first wave ring 211 (i.e., when the bare support 21 and the membrane support 22 are in a flipped-connected but uncompressed unfolded state, such as...). Figure 15 As shown, the bare support 21 at this time is at an angle of approximately 180° to the bare support 21 in its natural state, and is compressed and loaded into the sheath. The flipping fulcrum of the first wave coil 211 is the connection point between the first wave coil 211 and the coating.

[0075] One end of the folding rod structure 23 is fixedly connected to the wave rod of the first wave coil 211, and the other end is fixedly connected to the wave rod of the second wave coil 2211 that is closest to it. The folding rod structure 23 also includes a folding point F, such as... Figure 15As shown, one end of the folding rod structure 23 is fixed to the midpoint of the wave rod of the first wave ring 211 (the midpoint of the wave rod between adjacent troughs and crests) or any position between the midpoint and the crest, so that when the folding rod structure 23 automatically folds back to its natural state from the folded state with the folding point F as the fulcrum, the torque on the first wave ring 211 is relatively large (the fulcrum of the first wave ring 211 when it flips back to its natural state is as follows). Figure 15 The trough of the first wave circle 211 shown).

[0076] The folding rod structure 23 also includes a folding part 231, a fixing part 232, and a resiliently foldable connecting point. One end of the folding part 231 is fixed to the wave rod of the first wave ring 211 via a cylinder sleeve 231, and the other end is connected to the fixing part 232 via the resiliently foldable connecting point, which is the folding point F, and the folding point F is within the film-coated support 22. One end of the fixing part 232 is fixed to the wave rod of the second wave ring 2211 via a cylinder sleeve, and the fixing part 232 is fixed within the film-coated 222, while the other end is fixed to the folding part 231. The folding rod structure 23 in its natural state is as follows... Figure 14 As shown, the folding part 231 and the fixing part 232 are folded together at the folding point F and integrally formed; in the flipped state, as Figure 15 As shown, the fold 231 folds outward toward the film support 22 with the fold point F as the fulcrum, and has a tendency to fold back to its natural state.

[0077] In this embodiment, the folding rod structure 23 is made of a metallic elastic material (e.g., nickel-titanium alloy). The folding rod structure 23 is fixed to the first wave coil 211 and the second wave coil 2211 by pressing it with the cylinder liner 231 or by welding binding wire.

[0078] One or more foldable folding rod structures 23 can be provided. The folding rod structure 23 should provide enough force to drive the first wave coil 211 back to its natural state when it folds back from its flipped state. The foldable folding rod structure 23 is S-shaped with smooth transitions at both ends for easy connection with the wave rods on the wave coil. In other embodiments, an even number of folding rod structures 23 are provided, and each pair is circumferentially symmetrical relative to the axis of the coating support 22, ensuring balanced force distribution during the process of the first wave coil 211 folding back to its natural state.

[0079] The lumen stent 20 provided in this embodiment is Figure 15The bare stent 21 is compressed and loaded into the sheath of the delivery device in the flipped state shown. At this time, the angle between the bare stent 21 and the bare stent in its natural state is approximately 180°. When the lumen stent 20 is delivered using the delivery device 70, both the bare stent 21 and the covered stent 22 are in a compressed state. The complete release process of the lumen stent 20 provided in this embodiment includes, in sequence, a compressed state, a post-release state, and a natural state. The process from the compressed state to the post-release state also includes retracting the sheath to release the covered stent (the compressed state can be referred to...). Figure 10 ).

[0080] The compression state in this embodiment can be referred to in Embodiment 1, and will not be repeated here. The main difference between the release process of the bare support 21 and Embodiment 1 is that it does not include the process of using the external force of the hook structure 71 of the conveyor to move the first wave ring 211 of the bare support 21 from the first release state to the subsequent release state. That is, in this embodiment, when the first wave ring 211 is in the first release state as in Embodiment 1, the hook structure 71 can be controlled to make the first wave ring 211 disengage from the anchor 712 to achieve subsequent release. In other words, the subsequent release state coincides with the first release state. The flipping of the bare support 21 in this embodiment is an active flipping: after being directly released from the first release state, it automatically flips back to its natural state.

[0081] like Figure 16 As shown, the luminal stent 20 is in the post-release state. Before this, the luminal stent 20 is in the self-compressed state. The covered stent 22 is released by retracting the sheath 73, so that the covered stent 22 fits the blood vessel.

[0082] After the release state, the inner and outer sheath cores of the sheath core assembly 72 are controlled to disengage the first wave coil 211 from the anchor 712. Since both the first wave coil 211 and the folding rod structure 23 are in a flipped state, and the folding rod structure 23 is a single-rod structure, the folding rod structure 23 has a strong tendency to fold back to its natural state from its flipped state. This can cause the first wave coil 211 to flip back to its natural state (i.e., be stored inside the film-coated bracket 22 and attached to it). Figure 17 As shown. The luminal stent 20 provided in this embodiment can prevent interference with vascular branches after the bare stent 21 is fully deployed. This avoids the bare stent 21 blocking the entrance to the branch artery, thus preventing blood supply disruption; it also prevents the bare stent 21 from pressing against the inside of the branch vessel 53, thus preventing branch vessel dissection. Without increasing the assembly volume of the luminal stent 10, it can automatically flip back into the covered stent 22 after post-deployment, enhancing the sealing effect at the proximal end of the luminal stent 20 and reducing endoleak and stent displacement. The automatic flipping of the bare stent into the covered stent, without the need for external force in the post-deployment state, reduces the risk of stent displacement or shortening that might occur due to the need for external force provided by the delivery device's hook structure, compared to passive flipping.

[0083] Example 3

[0084] Example 3 proposes a lumen stent 30 and a lumen stent system, such as Figure 18-19 As shown. The features of the lumen stent 30 and lumen stent system in Embodiment 3 that are the same as or can be reused from Embodiment 1 will not be repeated here. The main difference is that the bare stent 31 of the lumen stent 30 in Embodiment 3 includes a first wave 311 located within the covered stent in its natural state. The covered area from the trough of the second wave 311 along the axial direction to the proximal end of the covered stent 32 is defined as the first region M. The first wave 311 in its natural state includes a fixed wave 3111 as a fixing part and a reversible non-fixed wave. The fixing part includes at least one fixed wave, and the fixed wave 3111 is fixed within the first region. The non-fixed wave can be flipped relative to the fixed wave 3111 to form a flipped wave 3112. In the flipped state, the reversible non-fixed wave flips out of the covered stent 32 to form the flipped wave 3112. The flipped wave serves as the flipping part, and the flipping part includes at least one flipped wave. The covered area from the crest of the second wave 3211 along the axial direction to the proximal end of the covered stent 32 is defined as the second region N, and the fulcrum of the flipped non-fixed wave is located within the second region, as shown. Figure 18 As shown.

[0085] In this embodiment, there are four reversible, non-fixed waves (defined as a wave of one cycle), including two adjacent waves and two other waves that are circumferentially symmetrical about the two adjacent waves along the axial direction of the covering support 32. Since four waves flip approximately 180° (e.g., Figure 18 As shown, the four overturning waves are compressed into the sheath and, when the lumen support 30 is released to the post-release state, are in the following state: Figure 19 In the flipped state shown, if the hooking action of the hook structure 71 is removed, with the fixed wave 3111 fixed to the membrane 322, the flipped wave 3112, due to the flipping deformation between itself and the adjacent fixed wave 3111, has a strong tendency to flip back to its natural state in the first wave ring 311. Therefore, when Figure 19 In the post-release state, the hook structure 71 is controlled to cause the flip wave 3112 to detach from the anchor 712, and the flip wave flips back into the film support 32 and attaches to the film 322.

[0086] When the flipped wave 3112 and the fixed wave 3111 are in the unfolded state of flipped connection, such as Figure 18 As shown, the flip wave 3112 and the second wave ring 3211 are spaced apart axially. The trough of the flip wave 3112 is located in the second region, and the axial distance D1 (refer to Embodiment 1) between the trough of the flip wave and the peak of the second wave ring satisfies: 0mm < D1 ≤ 3mm. The wave height of the flip wave is less than or equal to the tube radius of the covered stent, so that the flip wave can smoothly flip back into the covered stent.

[0087] In this implementation, the flipping wave 3112, which serves as the flipping part, is in a flipping state (e.g., ...). Figure 18 As shown, the trough of the wave 3112 and the crest of the second wave ring 3211 are not on the same straight line along the axial direction, while the trough of the flipped wave 3112 and the trough of the second wave ring 3211 are on the same straight line along the axial direction. The wave height of the flipped wave 3112 is equal to the wave height of the fixed wave 3111 and the wave height of the second wave ring 3211, so that the wave rod of the flipped wave 3112 can cross and support the coating when it flips back into the coating support 32.

[0088] The luminal stent 30 provided in this embodiment can prevent interference with vascular branches after the bare stent 31 is fully deployed. This avoids the bare stent 31 blocking the entrance to the branch artery, thus preventing impaired blood supply; it also prevents the bare stent 31 from pressing against the inside of the branch vessel 53, thus preventing branch vessel dissection. Furthermore, it can automatically flip back into the covered stent 32 after post-deployment, enhancing the sealing effect at the proximal end of the luminal stent 30 and reducing endoleak and stent displacement. The automatic flipping wave into the covered stent, without the need for external force in the post-deployment state, reduces the risk of stent displacement or shortening that might occur due to the need for external force provided by the delivery device's hook structure, compared to passive flipping.

[0089] The state of the first wave 311 of the bare stent 31 returning to the covered stent 32 after being released at the implantation site is similar to that of the first wave 311 of the bare stent 31. Figure 12 The difference is that in this embodiment, a portion of the first wave ring 311 is fixed to the film-coating support 32 to connect with the film-coating support 32, rather than in embodiment 1 where only the trough of the wave ring in its flipped state is connected to the film-coating support 32.

[0090] Example 4

[0091] Example 4 proposes a lumen stent 40 and a lumen stent system, such as Figure 20-21 As shown. The features of the lumen stent 40 and lumen stent system of Embodiment 4 that are the same as or can be reused from Embodiment 1 will not be described again here. The main difference is that the first wave 411 of the bare stent 41 of the lumen stent 40 of Embodiment 4 includes at least one individual folded wave, instead of a complete wave loop connected end to end. The folded wave is naturally located within the covered stent 42.

[0092] like Figure 20As shown, the folded wave includes a connecting portion 4112 and a bending portion 4111. The connecting portion 4112 is attached to the film-coated bracket 42, and one end of the connecting portion 4112 is fixed to the wave rod of the second wave coil 4211 by a cylinder liner 4113 or a welding binding wire. The other end of the connecting portion 4112 is connected to the bending portion 4111. A single folded wave includes two connecting portions 4112 and one bending portion 4111. The bending portion 4111 includes the crest of the folded wave, and the bending portion 4111 can be integrally formed with the connecting portion 4112. In its natural state, the plane containing the bending portion 4111 is perpendicular to the plane containing the two connecting portions 4112, as shown. Figure 20 The α value shown is 90°.

[0093] In this embodiment, after the bent portion 4111 flips 90°, the folded wave is parallel to the plane containing the two connecting portions 4112, and is compressed in this flipped state to be loaded into the sheath of the delivery device 70. The fulcrum for the flipping of the bent portion 4111 is the connection point between the bent portion 4111 and the connecting portion 4112, and this connection point is located within the covered stent 42. This ensures that after the lumen stent 40 is released at the implantation site, the bent portion 4111 of the folded wave flips back to its natural state, and the bent portion 4111 is not exposed outside the covered stent 42. However, when the bent portion 4111 of the folded wave flips 90° relative to the connecting portion 4112, most of the bent portion 4111 is exposed outside the covered stent 42, facilitating hooking the folded wave onto the hook structure 71 of the delivery device 70 after the folded wave flips 90°, and facilitating subsequent release, such as... Figure 21 As shown.

[0094] In this embodiment, since the two connecting parts serve as fixing parts and the bent part serves as a flipping part, when entering the released state, as... Figure 21 As shown, the bent portion of the folded wave is in a flipped state and has a rebound force towards its natural state. At this time, the control hook structure 71 causes the folded wave to detach from the anchor 712 of the hook structure 71, so that the bent portion 4111 of the folded wave can flip back to its natural state with the connection point between the bent portion 4111 and the connecting portion 4112 as the fulcrum. The luminal stent 40 provided in this embodiment can prevent interference with vascular branches after the bare stent 41 is fully released. This can prevent the bare stent 41 from blocking the entrance of the branch artery, thereby avoiding affecting blood supply; it can also prevent the wave of the bare stent 41 from hitting the inside of the branch vessel 53, thereby avoiding branch vessel dissection. The bent portion automatically flips into the covered stent, and no external force is required in the post-release state. Compared with passive flipping, it can also reduce the risk of vascular stent displacement or shortening that may be caused by the need for external force provided by the hook structure of the delivery device.

[0095] In this embodiment, the lumen stent 40, in its natural state, has an angle α between the bending portion 4111 and the connecting portion 4112 of the bending wave in the range of [0°, 90°]. Therefore, the restoring force in the corresponding flipped state is relatively large (the angle required for the bending portion 4111 and the connecting portion 4112 to be flipped is larger than that required in the natural state). Of course, in other embodiments, the angle α between the bending portion 4111 and the connecting portion 4112 can also be (90°, 180°), as long as it is ensured that it is not exposed to the covered stent 42 in its natural state and is easy to hook and release from the hooking structure 71 when flipped. In the case of flipping under compression, the flipping angle of the bent part 4111 relative to the connecting part 4112 is 180-α. In the case of release, the flipping angle is less than 180-α. That is, in the natural state, the larger the angle α is, the smaller the angle of flipping deformation and the smaller the restoring force when flipping or in the case of release; in the natural state, the smaller the angle α is, the larger the angle of flipping deformation and the larger the restoring force when flipping or in the case of release.

[0096] The lumen stent 40 provided in this embodiment includes two circumferentially symmetrically arranged bent waves along the axial direction of the covered stent, with α = 90°. This ensures the balance and magnitude of the restoring force, and also ensures that the number of bent waves when flipped back to the natural state is small. Although the bent waves are not attached to the covered stent 42, they will not have a significant impact on blood flow. Furthermore, reducing the flipping angle can prevent unreliability caused by excessive deformation at the connection between the bent part 4111 and the connecting part 4112 (for example, it may lead to plastic deformation or breakage of the single wave rod).

[0097] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0098] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A lumen stent, wherein during delivery, the lumen stent comprises a covered stent and a bare stent connected proximal to the covered stent, characterized in that, The bare stent and the covered stent are flipped together so that after the bare stent is released from the conveyor, the bare stent flips into the covered stent; The bare support includes a first corrugated ring connected to the coated support. The coated support includes a main support and a coating covering the main support. The main support includes a plurality of corrugated rings arranged at intervals along the axial direction. The corrugated ring closest to the bare support is the second corrugated ring. When the bare support and the coated support are in the unfolded state of the flip connection, the first corrugated ring and the second corrugated ring are arranged at intervals along the axial direction with a gap, and the coating is connected at the gap. In its natural state, the bare stent is in contact with the membrane, and the angle between the bare stent and the membrane stent is 0°. When the lumen stent is compressed and loaded into the sheath for transport, the bare stent is in a flipped state, and the angle between it and the membrane stent is approximately 180°. In the released state, the first wave coil flips to an angle of less than 90° with the membrane. If no external force is applied, the first wave coil will flip back into the membrane stent and return to its natural state.

2. The lumen stent as described in claim 1, characterized in that, When the lumen stent is delivered, the bare stent is in a compressed state. The process of the bare stent flipping from the compressed state into the covered stent includes a compressed state, a first release state, a post-release state, and a natural state.

3. The lumen stent as described in claim 1, characterized in that, The coating is a PTFE film or a PET film.

4. The lumen stent as described in claim 1, characterized in that, The covered stent is a hollow tube in its natural state. The radius of the tube of the covered stent is defined as R, and the wave height of the first wave ring is defined as H. Then H satisfies: H≤R.

5. The lumen stent as described in claim 1, characterized in that, The axial distance D between the trough of the first wave loop and the crest of the second wave loop satisfies: 0mm < D ≤ 3mm.

6. The lumen stent as described in claim 1, characterized in that, The trough of the first wave loop and the peak of the second wave loop are connected by polymer lines.

7. The lumen stent as described in claim 1, characterized in that, The trough of the first wave loop and the crest of the second wave loop are not on the same straight line along the axial direction.

8. The lumen stent as described in claim 1, characterized in that, The troughs of the first wave loop and the troughs of the second wave loop are on the same straight line along the axial direction.

9. The lumen stent as described in claim 8, characterized in that, Each single wave in the first wavering is at the same height, and the wave heights of the first wavering and the second wavering are at the same height.

10. The lumen stent as described in claim 9, characterized in that, The first wave cycle and the second wave cycle have the same wave period.

11. The lumen stent as described in claim 2, characterized in that, The process of the bare stent from the first released state to the natural state includes passive flipping or automatic flipping.

12. A lumen stent system, characterized in that, The device includes a delivery device and a lumen stent as described in any one of claims 1-11, wherein the delivery device includes a sheath and a sheath core assembly, and a receiving cavity for receiving the lumen stent is formed between the sheath and the sheath core assembly.

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