An intravascular implant

Abstract

The present invention discloses an intravascular implant, which relates to the field of medical devices. The intravascular implant includes a proximal bare coil, a first fixing coil and a stent body. The top part of the stent body is connected with the first fixing coil. Both ends of the proximal bare coil are connected to the first fixing coil, and the proximal bare coils are evenly distributed in the circumferential direction of the stent body. The present invention proposes a novel lumen implant. Its special structure lies in that the proximal bare coils of the stent are movable. When the stent is loaded in the delivery device, the proximal bare coils extend out. Its effect is the same as that of a conventional bare coil, which is used to anchor the stent and then release it. After the stent is completely released at a designated position in the blood vessel, the proximal bare coils can automatically retract and hide in the stent membrane-covered area, avoiding the contact between the bare coils and the blood vessel inner wall, thereby reducing the damage of the stent to the blood vessel intima.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and specifically to an intravascular implant. Background Art

[0002] As an aortic implant widely used clinically at present, the lumen stent is mainly composed of a metal skeleton and a polymer membrane. In order to increase the anchoring area and wall attachment of the stent, a bare stent wave loop is provided at the proximal end of the stent. The bare stent wave loop can enable the stent to be placed across branches, and at the same time, it can enable post-release of the stent to increase the accuracy and safety of stent release.

[0003] With the development of endovascular treatment, industry experts have realized that the bare wave loop at the proximal end of the stent will increase the irritation to the vascular intima in the blood vessel, causing intimal injury. At the same time, after the stent is placed in place, the bare wave loop opens, and the release of the bare wave loop will have a large elastic force directly acting on the inner wall of the blood vessel, causing greater irritation to the blood vessel. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to provide an intravascular implant to solve the technical problems that the bare wave loop at the proximal end of the stent will increase the irritation to the vascular intima in the blood vessel, causing intimal injury, and at the same time, after the stent is placed in place, the bare wave loop opens, and the release of the bare wave loop will have a large elastic force directly acting on the inner wall of the blood vessel, causing greater irritation to the blood vessel.

[0005] To achieve the above purpose, the present invention provides the following technical solution: an intravascular implant, which includes a proximal bare wave loop, a first fixed wave loop and a stent body. The top part of the stent body is connected with the first fixed wave loop. Both ends of the proximal bare wave loop are connected to the first fixed wave loop, and the proximal bare wave loops are evenly distributed in the circumferential direction of the stent body.

[0006] By adopting the above technical solution, the bare wave loop at the proximal end of the stent is movable. When the stent is loaded in the delivery device, the proximal bare wave loop extends out, and its effect is the same as that of a conventional bare wave loop, which is used for anchoring the post-release of the stent. After the stent is completely released at a specified position in the blood vessel, the proximal bare wave loop can automatically retract and hide in the stent covering area, avoiding contact between the bare wave loop and the inner wall of the blood vessel, thereby reducing the damage of the stent to the vascular intima.

[0007] The present invention is further configured such that the proximal bare wave loop and the first fixed wave loop are fixedly connected by one of crimping or welding. The connection points between the proximal bare wave loop and the first fixed wave loop need to be spaced by at least one wave. After the stent body is completely released, the proximal wave crest of the proximal bare wave loop is not higher than the wave crest of the first fixed wave loop, and the wave crest of the first fixed wave loop is the starting position of the proximal coating of the stent.

[0008] By adopting the above technical solution, after the stent body 3 is released into the blood vessel and opened, the bare stent wave loops are not in contact with the inner membrane of the blood vessel wall when the stent is released in the blood vessel cavity, so as to reduce the irritation to the blood vessel. When the stent body 3 is compressed or loaded into the delivery catheter, since the proximal bare wave loop 1 and the first fixed wave loop 2 are cross-connected, the proximal bare wave loop 1 after compression is longer than the first fixed wave loop 2 in the axial direction. Therefore, the proximal bare wave loop 1 will protrude from the proximal end of the stent body 3 into the covered area. The post-release mechanism on the delivery device can be used to anchor and control the post-release of the stent after the compressed bare stent is installed on the delivery device.

[0009] The present invention is further configured such that the proximal bare wave loop and the first fixed wave loop are movably connected through an "8"-shaped movable ring. The "8"-shaped movable ring can freely slide between the wave crests and wave troughs of the first fixed wave loop. When the stent body is compressed, the "8"-shaped movable ring naturally slides towards the wave crest of the first fixed wave loop. At this time, the wave crest of the proximal bare wave loop is higher than the wave crest of the first fixed wave loop. After the stent body is released, the "8"-shaped movable ring on the proximal bare wave loop will slide towards the distal end of the stent to the wave trough under the action of the wave loop elastic force. At this time, the wave crest of the proximal bare wave loop will be lower than the wave crest of the first fixed wave loop and coincide with the covered area.

[0010] By adopting the above technical solution, it can be used for fixing during the loading of the stent delivery device and controlling the release and positioning of the stent, avoiding direct contact with the inner wall of the blood vessel and reducing the irritation to the blood vessel endothelium.

[0011] The present invention is further configured such that the proximal bare wave loop is reversely fixedly connected to the first fixed wave loop through a connecting sleeve. When the stent body is in the compressed state, the wave crest of the proximal bare wave loop is flipped towards the proximal end of the stent and the wave crest of the proximal bare wave loop is higher than the wave crest of the first fixed wave loop.

[0012] By adopting the above technical solution, the bare wave loop can be used for stent positioning during the loading, anchoring and release process of the stent. Since the proximal bare wave loop 1 is fixedly connected to the first fixed wave loop 2 in an inverted manner, after the stent is released and opened in the blood vessel cavity, under the elastic action of the bare wave loop, the wave crest of the proximal bare wave loop 1 will rebound towards the distal end of the stent from the lumen. At this time, the wave crest of the bare wave loop is lower than the wave crest of the first fixed wave loop 2, and the entire bare wave loop is covered by the stent membrane, avoiding contact between the bare wave loop and the blood vessel endothelium.

[0013] In summary, the present invention mainly has the following beneficial effects:

[0014] The present invention provides a novel lumen implant. Its special structure lies in that the proximal bare coil of the stent is movable. When the stent is loaded in the delivery device, the proximal bare coil extends out. Its effect is the same as that of a conventional bare coil, which is used to anchor the stent and then release it. After the stent is completely released at the designated position in the blood vessel, the proximal bare coil can automatically retract and hide in the stent covering area, avoiding contact between the bare coil and the inner wall of the blood vessel, thereby reducing the damage of the stent to the vascular intima. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 FIG. is a schematic structural view of the intravascular implant according to Embodiment 1 of the present invention;

[0016] Figure 2 FIG. is a schematic structural view of the intravascular implant according to Embodiment 1 of the present invention after being crimped;

[0017] Figure 3 FIG. is a schematic structural view of the intravascular implant according to Embodiment 2 of the present invention;

[0018] Figure 4 FIG. is an enlarged schematic view of the proximal bare coil according to Embodiment 2 of the present invention;

[0019] Figure 5 FIG. is a schematic structural view of the stent after release according to Embodiment 2 of the present invention;

[0020] Figure 6 FIG. is a schematic connection view of the proximal bare coil and the first fixed coil according to Embodiment 3 of the present invention;

[0021] Figure 7 FIG. is a schematic structural view of the intravascular implant according to Embodiment 3 of the present invention.

[0022] In the figure: 1. Proximal bare coil; 11. "8"-shaped movable ring; 12. Connecting sleeve; 2. First fixed coil; 3. Stent body. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention and should not be construed as limiting the present invention.

[0024] The following will describe the embodiments according to the overall structure of the present invention. Embodiment

[0025] As Figure 1 shown, the lumen stent is divided into a proximal bare coil 1, a first fixed coil 2 and a stent body 3. Among them, the proximal bare coil 1 and the first fixed coil 2 are fixedly connected by crimping or welding. Moreover, the connection point between the proximal bare coil 1 and the first fixed coil 2 must be separated by at least one wave, and the proximal bare coils 1 are evenly distributed in the circumferential direction of the stent body 3; AsFigure 1 As shown in the figure, after the stent body 3 is completely released, the proximal peak of the proximal bare coil 1 is not higher than the peak of the first fixed coil 2, and the peak of the first fixed coil 2 is the starting position of the proximal membrane of the stent. After the stent body 3 is released and opened in the blood vessel, the bare stent coils of the stent are not in contact with the intima of the blood vessel wall when released in the blood vessel cavity, so as to reduce the irritation to the blood vessel.

[0026] As Figure 2 shown, when the stent body 3 is crimped or loaded into the delivery catheter, since the proximal bare coil 1 and the first fixed coil 2 are cross-connected, the proximal bare coil 1 after crimping is longer than the first fixed coil 2 in the axial direction. Therefore, the proximal bare coil 1 will extend out of the coated area from the proximal end of the stent body 3. The post-release mechanism that can be installed on the delivery device after the bare stent is crimped is used for stent anchoring and post-release control, so as to achieve the same effect as the bare stent in the prior art.

[0027] In this embodiment, a bare stent structure is proposed in which the peak of the proximal bare coil 1 is higher than the peak of the first fixed coil 2 after the stent is crimped, which is convenient for stent loading, anchoring and post-release control. After the stent is released, the bare stent retracts into the coated area. This structure can make the stent released in the blood vessel cavity avoid the contact between the bare stent wire and the blood vessel intima, reduce the irritation of the blood vessel intima. At the same time, the opening process of the bare stent is a slow process, avoiding large elastic force directly acting on the inner wall of the blood vessel and causing damage to the blood vessel intima. Embodiment

[0028] As Figure 3 shown, the lumen stent is divided into a proximal bare coil 1, a first fixed coil 2 and a stent body 3. The enlarged schematic diagram of the proximal bare coil 1 is as Figure 4 shown. The proximal bare coil 1 and the first fixed coil 2 are movably connected through an "8"-shaped movable ring 11. The "8"-shaped movable ring 11 can freely slide between the peaks and valleys of the first fixed coil 2. When the stent is compressed, the "8"-shaped movable ring 11 naturally slides towards the peak of the first fixed coil 2, making the peak of the proximal bare coil 1 higher than the peak of the first fixed coil 2. At this time, the proximal bare coil 1 has the same effect as the fixed bare coil in the prior art and can be used for fixing and controlling the release position of the stent when loading the delivery device.

[0029] When the stent release is completed, as Figure 5 shown, the "8"-shaped movable ring 11 on the proximal bare coil 1 will slide towards the distal end of the stent to the valley under the action of the coil elastic force. At this time, the peak of the proximal bare coil 1 will be lower than the peak of the first fixed coil 2 and coincide with the coated area, avoiding direct contact with the inner wall of the blood vessel and reducing the irritation to the blood vessel intima.

[0030] This embodiment provides a novel proximal bare coil structure of a stent. The "8"-shaped movable ring 11 enables the bare coil to extend and retract as the stent compresses and opens, so that the bare stent is fixed on the conveyor during the stent crimping and loading process, and retracts to the stent covered membrane section after the stent is completely released, avoiding direct contact between the bare coil of the stent and the vascular intima and reducing intimal injury. At the same time, after the post-release opening, the bare coil does not instantaneously rebound and hit the vascular intima, but retracts backward along the first fixed coil, reducing the irritation to the vascular intima during the release process. Embodiment

[0031] As Figure 6 shown, the proximal bare coil 1 of the stent is reversely fixedly connected to the first fixed coil 2 through a connecting sleeve 12, and its fixed position can be adjusted according to the size and waveform structure of the proximal bare coil 1. It is necessary to ensure that when the stent is in the crimped state, the wave crest of the proximal bare coil 1 is flipped towards the proximal end of the stent and the wave crest of the bare coil is higher than the wave crest of the first fixed coil 2. At this time, the bare coil can be used for stent loading anchoring and stent positioning during the release process.

[0032] Since the proximal bare coil 1 is fixedly connected to the first fixed coil 2 in an inverted manner, after the stent is released and opened in the blood vessel lumen, under the elastic action of the bare coil, the wave crest of the proximal bare coil 1 will rebound from the lumen towards the distal end of the stent. At this time, the wave crest of the bare coil is lower than the wave crest of the first fixed coil 2, and the entire bare coil is covered by the stent membrane, avoiding contact between the bare coil and the vascular intima and reducing the irritation and damage of the bare coil metal to the vascular intima.

[0033] This embodiment proposes a new proximal bare coil structure. Through the inverted structure of the bare coil, the bare coil is elastically deformed during the stent loading process, bending from the lumen towards the proximal end of the stent. At the same time, the wave crest of the bare coil is higher than the wave crest of the first fixed coil, enabling the bare coil to play the role of the bare coil in the prior art during the loading and release processes. After the stent is completely released, under the elastic force of the proximal bare coil 1, the proximal bare coil 1 returns to the state where the wave crest faces the distal end, avoiding direct contact between the bare coil and the vascular intima, reducing repeated friction with the metal coil during blood vessel peristalsis, reducing the risk of vascular intimal hyperplasia and vascular perforation, and improving the surgical success rate and long-term implantation safety.

[0034] Although the embodiments of the present invention have been shown and described, this specific embodiment is only an explanation of the present invention and is not a limitation of the invention. The specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. After reading this specification, those skilled in the art can make modifications, substitutions, and variations that do not contribute creatively to the embodiments according to needs, but as long as they are within the scope of the claims of the present invention, they are protected by the patent law.

Claims

1. An intravascular implant, characterized in that: The endovascular implant includes a proximal bare coil (1), a first fixing coil (2) and a stent body (3). The top part of the stent body (3) is connected with the first fixing coil (2). Both ends of the proximal bare coil (1) are connected to the first fixing coil (2), and the proximal bare coils (1) are evenly distributed in the circumferential direction of the stent body (3). The proximal bare coil (1) and the first fixing coil (2) are movably connected through an "8"-shaped movable ring (11). The "8"-shaped movable ring (11) can freely slide between the peaks and valleys of the first fixing coil (2). When the stent body (3) is compressed, the "8"-shaped movable ring (11) naturally slides towards the peak of the first fixing coil (2). At this time, the peak of the proximal bare coil (1) is higher than the peak of the first fixing coil (2). After the stent body (3) is completely released, the "8"-shaped movable ring (11) on the proximal bare coil (1) will slide towards the distal end of the stent to the valley under the action of the coil elastic force. At this time, the peak of the proximal bare coil (1) will be lower than the peak of the first fixing coil (2), coinciding with the covered area.

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