Intravascular positioning stent for human body

Abstract

The application discloses a human body intravascular positioning stent and relates to the field of medical devices. The stent comprises a metal wire stent, which is used for being unfolded in a human body blood vessel to expand the blood vessel. A plurality of positioning units are arranged on the metal wire stent. The positioning unit comprises a spring and a piercing positioning head fixedly connected with the distal end of the spring. The proximal end of the spring is fixedly connected with the metal wire stent. The piercing positioning head is used for piercing the inner wall of the blood vessel to realize positioning when the metal wire stent is unfolded. The positioning unit designed by the spring combined with the piercing positioning head realizes the unity of stable fixation and safe extraction of the intravascular positioning stent.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and in particular to an intravascular positioning stent for human blood vessels. Background Technology

[0002] Various causes can lead to blockages or narrowings in blood vessels, such as sudden thrombosis. Interventional stent placement is a routine and effective treatment for vascular stenosis or blockage. However, existing stents have revealed significant problems in long-term clinical use: First, in vascular environments with high blood flow or high blood pressure, especially in elderly patients with poor vascular elasticity, stents are prone to displacement, affecting treatment efficacy and posing risks. Second, as foreign bodies, stent implantation can trigger intimal hyperplasia (i.e., "skin climbing"), potentially leading to restenosis, and requiring long-term anti-rejection medication, placing a heavy burden on patients. To mitigate these long-term risks, removing stents after fulfilling their temporary support function has become a new clinical trend. However, existing solutions face a dilemma: rigid barbs or anchoring structures designed to prevent displacement, while effectively fixing the stent, are prone to snagging, cutting, or even tearing the vessel wall during removal, causing severe secondary damage. This makes "stable fixation" and "safe removal" a difficult contradiction to reconcile. Therefore, developing a vascular stent that can be reliably positioned in a complex hemodynamic environment during the initial implantation stage and can be smoothly and safely removed when needed is of vital importance for improving the overall safety of interventional therapy and reducing patient suffering. Summary of the Invention

[0003] In view of the above-mentioned defects or deficiencies in the prior art, the present invention provides an intravascular positioning stent that achieves both stable fixation and safe removal of the intravascular positioning stent.

[0004] The present invention provides an intravascular positioning stent, comprising: A wire stent is used to expand blood vessels in the human body. The wire stent is provided with multiple positioning units, each of which includes a spring and an insertion positioning head fixedly connected to the distal end of the spring. The proximal end of the spring is fixedly connected to the wire support, and the piercing positioning head is used to pierce the inner wall of the blood vessel when the wire support is deployed to achieve positioning.

[0005] Furthermore, the proximal end of the spring is wound or welded to the wire support, and the connection between the wire support and the spring forms a recess.

[0006] Furthermore, the angle between the axis of the spring and the axis of the wire support is 20° to 90°.

[0007] Furthermore, the multiple positioning units are arranged at equal or non-equal intervals on the wire support.

[0008] Furthermore, the piercing positioning head includes a wire skeleton with a tip and a biodegradable coating layer with a tip covering the wire skeleton.

[0009] Furthermore, the distance between the tip vertex of the wire skeleton and the tip vertex of the covering layer is 0.1~0.2mm.

[0010] Furthermore, a raised ring is provided on the covering layer, and the distance between the center of the front end face of the raised ring and the tip of the covering layer is 0.2~0.4mm.

[0011] Furthermore, the piercing positioning head is a combination of a frustum and a cone.

[0012] Furthermore, the frustum portion of the frustum-cone assembly is fixedly connected to the spring, and the height of the conical portion of the frustum-cone assembly is 0.1~0.3mm.

[0013] Furthermore, the frustum-cone combination is made of a biodegradable material.

[0014] This invention provides a positioning stent for intravascular use. Through a positioning unit design combining a spring and an insertion-type positioning head, it achieves both stable fixation and safe removal of the intravascular positioning stent. Initially, under the elastic force of the spring, the tip of the insertion-type positioning head can moderately penetrate the inner wall of the blood vessel. Multiple positioning units work together to provide excellent anti-displacement capability, ensuring the stability of the positioning stent in complex blood flow environments. When the positioning stent needs to be removed, the inherent flexibility and bendability of the spring allow it to undergo compliant bending deformation when the insertion-type positioning head is subjected to the axial tension of the wire stent. This allows the insertion-type positioning head to smoothly and obliquely detach from the blood vessel tissue, greatly reducing the risk of cutting and tearing the inner wall of the blood vessel. Furthermore, the biodegradable material used in the insertion-type positioning head gradually degrades over time, actively reducing its structural rigidity. This not only further facilitates the removal operation but also, through self-optimization of the structural design, achieves a transition from stable fixation to safe removal of the positioning stent, improving the overall safety of interventional therapy. Attached Figure Description

[0015] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of an intravascular positioning stent structure provided in one embodiment of this application; Figure 2This is a schematic diagram of the internal positioning unit structure of an intravascular positioning stent provided in one embodiment of this application; Figure 3 This is a schematic diagram of the internal positioning unit structure of an intravascular positioning stent provided in another embodiment of this application; Among them, 100-metal wire support; 200-positioning unit; 210-spring; 220-insertion positioning head; 221-metal wire skeleton; 222-covering layer; 223-convex ring; 300-blood vessel. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” used in the embodiments of this invention are also intended to include the plural forms unless the context clearly indicates otherwise.

[0018] It should be understood that although the terms first, second, third, etc., may be used to describe the acquisition modules in the embodiments of the present invention, these acquisition modules should not be limited to these terms. These terms are only used to distinguish the acquisition modules from each other.

[0019] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0020] It should be noted that the directional terms such as "upper," "lower," "left," and "right" used in the embodiments of the present invention are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the embodiments of the present invention. Furthermore, in the context, it should be understood that when it is mentioned that an element is formed "upper" or "lower" of another element, it can not only be formed directly "upper" or "lower" of the other element, but also indirectly "upper" or "lower" of the other element through an intermediate element.

[0021] refer to Figure 1-3This invention provides an intravascular positioning stent, including a wire stent 100, for deployment within a blood vessel to expand the vessel. Optionally, the wire stent 100 can be a spiral, mesh, or other deployable structure. The wire stent 100 is provided with multiple positioning units 200. Each positioning unit includes a spring 210 and an insertion positioning head 220 fixedly connected to the distal end of the spring 210. The distal end of the spring 210 is the end of the spring 210 that is away from the wire stent 100.

[0022] The proximal end of spring 210, i.e., the end of spring 210 close to the wire stent 100, is wound or welded to the wire stent 100. The piercing positioning head 220 is used to pierce the inner wall of blood vessel 300 to achieve positioning when the wire stent 100 is deployed. In actual use, the wire stent 100 is placed in the human blood vessel at the position that needs to be expanded via a delivery device. After the wire stent 100 is deployed, under the radial elastic force of the wire stent 100 and the tensile force of spring 210, the piercing positioning head 220 can pierce the inner wall of blood vessel 300, thereby hindering the displacement of the wire stent 100 in blood vessel 300. When the positioning stent needs to be removed, the elastic structure of positioning unit 200 will deform and bend the positioning unit 200, further reducing the force between the positioning unit 200 and the inner wall of blood vessel 300, making it easier to remove the positioning stent, avoiding damage to blood vessels when removing the positioning stent, greatly improving safety, and avoiding long-term rejection reactions of the positioning stent in the human body.

[0023] Specifically, the angle between the axis of spring 210 and the axis of wire support 100 is 20°~90°. Spring 210 is coaxial with the insertion positioning head 220. When the angle is 90°, the tension of spring 210 is almost entirely applied to the tip of insertion positioning head 220, resulting in good positioning effect and easier removal. When the angle is 20°, insertion positioning head 220 is similar to a barb inserted and fixed to the inner wall of blood vessel 300, resulting in better positioning effect, but removal is more inconvenient. Considering both positioning effect and ease of removal, preferably, the angle between the axis of wire support 100 and the axis of spring 210 is 60°~45°. The specific angle is determined by factors such as the actual usage environment, blood flow velocity, and blood vessel diameter.

[0024] The connection between the wire support 100 and the spring 210 forms a recess (not shown in the figure). When the wire support 100 unfolds in the blood vessel 300 and contacts the inner wall of the blood vessel 300, if the angle between the axis of the spring 210 and the axis of the wire support 100 is large, the tip of the puncture positioning head 220 will be subjected to a large force, which may easily puncture the blood vessel. When the connection between the wire support 100 and the spring 210 is set as a recess, a part of the spring 210 can be placed in the recess, and the elastic pressure on the tip of the puncture positioning head 220 will be appropriately reduced, thus avoiding puncture damage to the blood vessel 300.

[0025] Multiple positioning units 200 can be arranged at equal intervals or at non-equal intervals on the wire support 100. The non-equal interval arrangement can be determined according to the shape of the blood vessel, the blood flow velocity and the blood pressure during specific use. Such arrangement includes axial distribution and circumferential distribution on the wire support 100.

[0026] refer to Figure 2 In one feasible embodiment, the invasive positioning head 220 includes a wire skeleton 221 with a pointed tip and a biodegradable covering layer 222 with a pointed tip covering the wire skeleton 221. The distance between the tip of the wire skeleton 221 and the tip of the covering layer 222 is 0.1~0.2mm, thereby ensuring that the covering layer 222 completely covers the wire skeleton 221, thus improving the strength and rigidity of the invasive positioning head 220. After the positioning stent is implanted in the human body for a period of time, the covering layer 222 made of biodegradable material in the invasive positioning head 220 will gradually degrade. This degradation process will reduce the strength and rigidity of the invasive positioning head 220. If the positioning stent is placed in the human body for a longer period of time until the covering layer 222 is completely degraded, the tip of the wire skeleton 221 will still penetrate the inner wall of the blood vessel 300 under the action of the spring 210. However, the reliability of positioning will be slightly reduced. While the temperature drops, the skin-covering phenomenon of the human body gradually coats the wire support 100, increasing the difficulty of displacement of the wire support 100. The reduction in strength and rigidity of the piercing positioning head 220 makes it easier to deform when the positioning support needs to be removed. Combined with the flexibility of the spring 210, the displacement of the wire support 100 will drive the proximal end of the spring 210 to move accordingly. Ultimately, the piercing positioning head 220, which only has the wire skeleton 221 left, can easily detach from the inner wall of the blood vessel 300. During the removal process, the wire skeleton 221 slides on the inner wall of the blood vessel 300 without causing damage to the inner wall of the blood vessel 300, which can greatly improve the safety of using and removing the positioning support. In addition, due to the presence of the biodegradable coating layer 222, the piercing positioning head 220 has high strength and rigidity, and the wire skeleton 221 can be made of thinner alloy wire, which makes it easier to remove the positioning support. A protruding ring 223 is provided on the covering layer 222. The distance between the center of the front end face of the protruding ring 223 and the tip of the covering layer 222 is 0.2~0.4mm. The front end face of the protruding ring 223 is the side of the protruding ring 223 that is close to the tip of the covering layer 222. With this design, the protruding ring 223 can limit the depth of the puncture positioning head 220 into the inner wall of the blood vessel 300, and avoid the blood vessel 300 being punctured, which could lead to bleeding or infection.

[0027] refer to Figure 3 In another feasible embodiment, the piercing positioning head 220 is a combination of a frustum and a cone. The inclined surface resistance of its conical part makes the piercing positioning head 220 piercing the blood vessel 300 at a controllable depth. When the positioning stent needs to be removed, the spring 210 bends first under the axial movement of the wire support 100, thereby making the spring 210 tilt. Then, the piercing positioning head 220 moves with the wire support 100 under the action of the inclined pulling force. Thus, the tip of the piercing positioning head 220 will not cut the blood vessel wall, but will slide along the moving direction of the wire support 100 with the inclined surface of the conical part against the inner wall of the blood vessel 300, ensuring that the blood vessel 300 will not be scratched. The frustum-cone combination is made of biodegradable material. When the positioning stent is placed in the blood vessel 300, it can maintain its strength and rigidity for a period of time, but it will gradually degrade. After a long time, the frustum-cone combination may be completely degraded, which will lead to a decrease in the positioning performance of the positioning unit 200. However, under the elastic force of the spring 210, the distal end of the spring 210 will still abut against the inner wall of the blood vessel 300 to maintain a certain positioning ability. At the same time, the human body's reaction during the longer retention time will cause the skin to climb and adhere to the wire stent 100, which will also increase the adhesion between the wire stent 100 and the inner wall of the blood vessel 300, thus ensuring that the positioning stent is not easily displaced. Furthermore, the degradation of the frustum-cone makes it easier to remove the positioning stent, further reducing the damage to the blood vessel 300 when removing the positioning stent and improving safety.

[0028] The frustum portion of the truncated cone assembly is fixedly connected to the spring 210. The height of the conical portion of the truncated cone assembly is 0.1~0.3mm. This size design ensures that the puncture positioning head 220 does not puncture the blood vessel 300, avoiding bleeding and infection. The inclined surface of the conical portion also provides some resistance to insertion.

[0029] This invention provides a positioning stent for intravascular use. Through a positioning unit design combining a spring and an insertion-type positioning head, it achieves both stable fixation and safe removal of the intravascular positioning stent. Initially, under the spring's elasticity, the tip of the insertion-type positioning head can moderately penetrate the vascular wall. Multiple positioning units work together to provide excellent anti-displacement capability, ensuring the stability of the positioning stent in complex blood flow environments. When the positioning stent needs to be removed, the inherent flexibility and bendability of the spring allow it to undergo compliant bending deformation when the insertion-type positioning head is subjected to the axial tension of the wire stent. This allows the insertion-type positioning head to smoothly and obliquely detach from the vascular tissue, greatly reducing the risk of cutting and tearing the vascular wall. Furthermore, the biodegradable material used in the insertion-type positioning head gradually degrades over time, actively reducing its structural rigidity. This not only further facilitates the removal operation but also, through self-optimization of the structural design, achieves a transition from stable fixation to safe removal of the positioning stent, improving the overall safety of interventional therapy.

[0030] The above description is merely a preferred embodiment of the present invention. Those skilled in the art should understand that the scope of disclosure in this invention is not limited to the specific combination of the above-described technical features, but should also cover other technical solutions formed by any combination of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this invention.

Claims

1. A human vascular positioning stent, characterized in that, include: A wire stent is used to expand blood vessels within the human body. The wire stent is provided with multiple positioning units, each including a helical spring and an insertion positioning head fixedly connected to the distal end of the helical spring. The helical spring is configured to undergo compliant bending deformation when the wire stent is subjected to axial tension, thereby causing the insertion positioning head to slide obliquely from the inner wall of the blood vessel. The proximal end of the helical spring is fixedly connected to the wire support, and the piercing positioning head is used to pierce the inner wall of the blood vessel when the wire support is deployed to achieve positioning. The angle between the axis of the helical spring and the axis of the wire support is 20°~90°. The piercing positioning head includes a metal wire skeleton with a tip and a biodegradable coating layer with a tip covering the metal wire skeleton. The distance between the tip of the wire skeleton and the tip of the covering layer is 0.1~0.2mm.

2. The intravascular positioning stent according to claim 1, characterized in that, The proximal end of the helical spring is wound or welded to the wire support, and the connection between the wire support and the helical spring forms a recess.

3. The intravascular positioning stent according to claim 1, characterized in that, The positioning units are arranged at equal or unequal intervals on the wire support.

4. The intravascular positioning stent according to claim 1, characterized in that, The coating layer is provided with a convex ring, and the distance between the center of the front end face of the convex ring and the tip of the coating layer is 0.2~0.4mm.

5. The intravascular positioning stent according to claim 1, characterized in that, The piercing positioning head is a combination of a frustum and a cone.

6. The intravascular positioning stent according to claim 5, characterized in that, The frustum portion of the truncated cone assembly is fixedly connected to the helical spring, and the height of the conical portion of the truncated cone assembly is 0.1~0.3mm.

7. The intravascular positioning stent according to claim 6, characterized in that, The frustum-cone combination is made of a biodegradable material.

Images