An easy-to-take-out positioning support with a positioning structure

Abstract

This invention discloses an easily removable positioning stent with a positioning structure, relating to the field of medical device technology. It includes a wire stent made of shape-memory metal for deployment within a blood vessel; multiple metal needles, each with a pointed tip for piercing the inner wall of the blood vessel and fixedly connected to the circumferential sidewall of the wire stent at its bottom; and multiple support arms fixedly connected to the circumferential sidewall of the wire stent and respectively connected at an angle to the multiple metal needles. Each support arm has a bent portion at its free end, formed by extending and bending itself, for pressing against the inner wall of the blood vessel. The height of the bending point of the bent portion from the wire stent is greater than the height of the tip of the metal needle from the wire stent. This invention, through the synergy of the metal needles and support arms, provides double fixation to ensure stable stent positioning. Simultaneously, the bent portion precisely limits the insertion depth of the metal needles, avoiding vascular damage, thus balancing positioning requirements and clinical safety.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to an easily removable positioning stent with a positioning structure. Background Technology

[0002] Interventional stents are a common treatment for vascular blockages or stenosis (such as sudden thrombosis), offering significant emergency relief. However, long-term use presents several challenges: stents are prone to displacement when blood flow is rapid or blood pressure is high, and elderly patients face even greater risks due to weakened vascular elasticity. Furthermore, the stent surface can "climb" onto the skin due to the body's natural response, potentially worsening vascular stenosis, requiring long-term anti-rejection medication. Therefore, removable stents are becoming a new trend in interventional vascular treatment.

[0003] To address the issue of stent displacement, existing designs employ two typical approaches, both with inherent drawbacks: one uses high-strength barbs to mechanically fix the stent in place by piercing the vessel wall. While this effectively restricts stent movement, it poses a significant safety hazard during subsequent retrieval due to adhesion and traction between the barbs and the vessel wall, leading to vessel wall tears. The other approach replaces the barbs with a single support arm whose free end is blunt, relying on the physical pressure of the support arm against the vessel wall for positioning. Although this avoids puncture damage to the vessel, the single support arm has limited support force and a small contact area with the vessel wall, making it difficult to withstand blood flow impacts and blood pressure fluctuations, allowing the stent to still easily shift. Therefore, ensuring stent positioning stability while maintaining safe retrieval remains a core challenge that urgently needs to be addressed in the field of interventional stent design. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, the present invention provides a removable positioning bracket with a positioning structure.

[0005] To achieve the above objectives, the present invention provides a removable positioning bracket with a positioning structure, comprising:

[0006] A wire scaffold, made of shape memory metal, is used to deploy in a blood vessel;

[0007] Multiple metal needles, the bottom of which are fixedly connected to the circumferential sidewall of the metal wire support, the top of the metal needles being a free end, the free end being a sharp point, and used to pierce the inner wall of the blood vessel;

[0008] Multiple support arms are fixedly connected to the circumferential sidewall of the wire support and are respectively connected at an angle to multiple metal needles. A bend is provided at the free end of the support arm, which is formed by extending and bending the support arm. The bend is used to press against the inner wall of the blood vessel.

[0009] The distance from the bending point of the bent portion to the metal wire support is greater than the distance from the tip of the metal needle to the metal wire support.

[0010] To achieve the above objectives, the present invention provides an easily removable positioning bracket with a positioning structure, which further includes a covering layer disposed on the outer periphery of the metal needle to completely enclose the metal needle.

[0011] The coating is made of a biodegradable material.

[0012] Preferably, the bending point is provided at the farthest end of the bending portion from the metal wire support, and the top of the metal needle is provided with a vertex, the height difference between the bending point and the vertex being 0.05-0.3mm.

[0013] Preferably, the angle between the centerline of the support arm and the centerline of the wire bracket is in the range of 30°-70°.

[0014] Preferably, the angle between the centerline of the metal needle and the centerline of the metal wire support is in the range of 85°-90°.

[0015] Preferably, when the metal needle is tilted, the tilting direction of the metal needle is consistent with the tilting direction of the support arm.

[0016] Preferably, the maximum diameter of the metal needle is smaller than the maximum diameter of the support arm.

[0017] Preferably, the bent portion is tapered, and the bending point is the tip of the tapered shape.

[0018] Preferably, the bending portion is configured as an arc shape, and the bending portion is achieved through a curve transition.

[0019] Preferably, the wire support is formed by weaving or spiraling multiple wires made of shape memory metal material.

[0020] Based on this, the beneficial effects of the present invention are as follows:

[0021] 1. This invention innovatively designs a collaborative structure of metal needle and support arm. After the metal wire stent is successfully deployed in the blood vessel, the metal needle accurately pierces the blood vessel wall with its tip, which can effectively limit the displacement of the stent. At the same time, the bent part of the support arm tightly presses against the inner wall of the blood vessel, realizing blood vessel support and maintaining blood vessel patency. Meanwhile, the elasticity of the support arm limits the piercing depth of the metal needle into the blood vessel wall, avoiding excessive damage to the blood vessel. Thus, the positioning stent can ensure positioning accuracy while taking into account the safety of use, effectively balancing the treatment effect and the need for vascular protection.

[0022] 2. The present invention, through the setting of the coating layer, can significantly enhance the rigidity and strength of the metal needle, further improve the positioning stability of the stent in the blood vessel, and reduce the risk of displacement. On the other hand, when the coating layer degrades as expected, the rigidity and strength of the metal needle will decrease accordingly, so that the connection between the metal needle and the blood vessel wall will naturally loosen. The stent can be easily removed from the blood vessel without complicated operations, which greatly simplifies the removal process, reduces the probability of secondary damage, and takes into account both the stability during the treatment process and the convenience of postoperative operation. Attached Figure Description

[0023] 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:

[0024] Figure 1 This schematic diagram illustrates the structure of the positioning bracket according to the first embodiment of the present invention.

[0025] Figure 2 Schematic representation of the present invention Figure 1 A magnified view of a section at point A in the middle;

[0026] Figure 3 This schematic diagram illustrates the structure of the positioning bracket according to a second embodiment of the present invention.

[0027] Figure 4 Schematic representation of the present invention Figure 3 A magnified view of a section at point B in the middle;

[0028] Explanation of reference numerals in the attached drawings: 10-Wire support, 20-Metal needle, 201-Vertex, 30-Support arm, 301-Bending part, 302-Bending point, 40-Covering layer. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0030] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms "a," "the," and "the" as used in the embodiments of this application are also intended to include the plural forms unless the context clearly indicates otherwise.

[0031] It should be understood that although the terms first, second, third, etc., may be used to describe related structures in the embodiments of this application, these related structures should not be limited to these terms. These terms are only used to distinguish related structures from each other.

[0032] Depending on the context, the word "if" as used here can be interpreted as "when" or "when". Similarly, depending on the context, the phrase "if determined" can be interpreted as "when determined" or "when (the condition or event of the statement) is detected".

[0033] It should be noted that the directional terms such as "upper," "lower," "left," and "right" described in the embodiments of this application are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should also 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.

[0034] Figure 1 This schematic diagram illustrates the structure of the positioning bracket according to the first embodiment of the present invention. Figure 2 Schematic representation of the present invention Figure 1 A magnified view of a portion of point A, as shown below. Figure 1 , 2 As shown, the present invention provides an easily removable positioning bracket with a positioning structure. In a first embodiment of the present invention, the solution includes:

[0035] The wire scaffold 10, made of shape memory metal material, is used to deploy in blood vessels;

[0036] Multiple metal needles 20, the bottom of which are fixedly connected to the circumferential sidewall of the metal wire support 10, and the top of the metal needles 20 are free ends, which are pointed tips and used to pierce the inner wall of blood vessels.

[0037] Multiple support arms 30 are fixedly connected to the circumferential sidewall of the wire support 10 and are respectively connected at an angle to multiple metal needles 20. A bent portion 301 formed by extending and bending the support arm 30 is provided at the free end of the support arm 30. The bent portion 301 is used to press against the inner wall of the blood vessel.

[0038] Specifically, the wire support 10 is configured as a tubular structure, which is formed by weaving or spiraling metal wires made of memory material, or by laser etching the tubular support.

[0039] Multiple metal needles 20 and multiple support arms 30 are provided on the circumferential sidewall of the metal wire stent 10. One metal needle 20 is connected to one support arm 30 at an angle and forms a set of positioning structures. The multiple sets of positioning structures are symmetrically distributed and equally spaced, or asymmetrically distributed and not equally spaced. When the metal wire stent 10 is placed in the blood vessel and unfolded, the metal needles 20 pierce the inner wall of the blood vessel, and the support arms 30 abut against the inner wall of the blood vessel.

[0040] A bend 301 is provided at the free end of the support arm 30. When the wire stent 10 is unfolded, the bend 301 presses against the inner wall of the blood vessel. After pressing, a depression is formed on the inner wall of the blood vessel. The bend 301 is partially embedded in the depression. The inner wall of the depression limits the movement of the bend 301, thereby limiting the movement of the wire stent 10. Together with the metal needle 20, it achieves the positioning function of the wire stent 10.

[0041] When the wire stent 10 unfolds, bringing the metal needle 20 and the bent portion 301 closer to the inner wall of the blood vessel, both come into contact with the inner wall: the metal needle 20 pierces the inner wall, while the bent portion 301 abuts against the inner wall and causes the support arm 30 to bend. Thanks to the elasticity of the support arm 30, when this elasticity balances with the pressure applied to the inner wall, the distance between the circumferential sidewall of the wire stent 10 and the inner wall remains stable, and the insertion depth of the metal needle 20 is limited. The design of the support arm 30 and the bent portion 301 prevents the metal needle 20 from excessively penetrating the blood vessel and causing additional damage.

[0042] Meanwhile, since the metal needle 20 and the bent part 301 contact the inner wall of the blood vessel through two action points, and there is a certain distance between the two action points and the inner wall of the blood vessel, that is, the circumferential sidewall of the metal wire stent 10 does not contact the inner wall of the blood vessel. The skin climbing (intima hyperplasia) caused by the body's rejection reaction will not cause the metal wire stent 10 to become one with the inner wall of the blood vessel due to skin climbing. When the metal wire stent 10 is removed, there is no resistance from skin climbing, making removal simpler. At the same time, it can also avoid the broken skin climbing that is torn and enters the blood, which may further cause vascular blockage, thus improving the safety of the positioning stent.

[0043] In addition, by controlling the elasticity of the material of the support arm 30 and the degree of expansion of the wire stent 10, it can be ensured that the metal needle 20 only penetrates the surface or superficial layer of the blood vessel wall, effectively improving the safety of the positioning stent.

[0044] Furthermore, in order to optimize the insertion depth of the metal needle 20 and ensure the safety of the positioning bracket, the present invention further includes:

[0045] A bending point 302 is provided at the farthest end of the bending portion 301 from the metal wire support 10, and a vertex 201 is provided at the top of the metal needle 20.

[0046] The height of the bending point 302 of the bending part 301 from the metal wire support 10 is greater than the height of the apex 201 of the metal needle 20 from the metal wire support 10.

[0047] With the above configuration, when the wire stent 10 is deployed, the bent portion 301 of the support arm 30 will first contact the inner wall of the blood vessel and bend, and then the metal needle 20 will contact the inner wall of the blood vessel and penetrate it. Under the premise that the elasticity of the material of the support arm 30 remains unchanged (i.e., the distance of the support arm 30 bending and descending is fixed), if the height of the support arm 30 is increased, the distance between the wire stent 10 and the inner wall of the blood vessel will increase after the elastic force and pressure are balanced, thereby reducing the depth of the metal needle 20 penetrating the inner wall of the blood vessel and further improving the safety of the positioning stent.

[0048] Furthermore, the height difference between the bending point 302 and the apex 201 is in the range of 0.05-0.3mm. This height difference can be determined based on factors such as the diameter of the blood vessel, the blood flow velocity, the elasticity or diameter of the support arm 30, and the radius or expansion force of the metal wire support 10 after it is deployed. Within this range, it can be ensured that the metal needle 20 penetrates the inner wall of the blood vessel to achieve the positioning function, and will not penetrate too deeply to cause additional damage to the blood vessel.

[0049] Furthermore, the angle between the centerline of the support arm 30 and the centerline of the wire stent 10 ranges from 30° to 70°. In actual use, the change in the angle between the centerline of the obliquely set support arm 30 and the centerline of the wire stent 10 will change the pressure exerted by the oblique support arm 30 on the inner wall of the blood vessel. The larger the angle between the two, the greater the pressure, and the smaller the angle, the smaller the pressure. That is, if the angle is smaller, it is easier to remove the positioning stent and less likely to scratch the inner wall of the blood vessel. The angle between the two stents can be precisely designed according to the actual use scenario to achieve better positioning effect, safety of use and ease of removal of the positioning stent.

[0050] Furthermore, the angle between the centerline of the metal needle 20 and the centerline of the metal wire support 10 is in the range of 85°-90°.

[0051] Specifically, when the angle between the centerline of the metal needle 20 and the centerline of the metal wire support 10 is 90°, the metal needle 20 is perpendicular to the circumferential sidewall of the metal wire support 10. At this time, the strength and rigidity of the metal needle 20 can be fully utilized, and the positioning effect of the positioning support is the best under this condition.

[0052] When the angle between the centerline of the metal needle 20 and the centerline of the metal wire support 10 is greater than or equal to 85° and less than 90°, that is, when the metal needle 20 is tilted, the tilting direction of the metal needle 20 and the support arm 30 is the same. Although the tilting setting of the metal needle 20 reduces its support effect to a certain extent, it is beneficial to locate the stent for removal in this case. When the metal wire support 10 is moved and removed in the opposite direction to the tilting direction of the metal needle 20, the tip of the metal needle 20 and the tilted support arm 30 slide in the same direction, which will not cause slippage or tearing of the inner wall of the blood vessel, and can greatly reduce the damage to the blood vessel.

[0053] Furthermore, the bending portion 301 of the support arm 30 can be set as a cone, with the bending point 302 being the tip of the cone. With this setting, the indentation formed after the bending portion 301 contacts the inner wall of the blood vessel can have a better limiting effect on the bending portion 301. At the same time, due to the cone-shaped setting, the bending portion 301 can penetrate the inner wall of the blood vessel to a smaller extent, further enhancing the fixation effect on the wire stent 10.

[0054] Furthermore, the bending portion 301 of the support arm 30 can also be configured as an arc shape, with the bending portion 301 achieving bending through a curve transition. This configuration can prevent the cone tip of the conical bending portion 301 from piercing the inner wall of the blood vessel, reducing damage to the inner wall of the blood vessel.

[0055] Furthermore, Figure 3 This schematic diagram illustrates the structure of the positioning bracket according to the second embodiment of the present invention. Figure 4 Schematic representation of the present invention Figure 3 A magnified view of a section at point B, as shown below. Figure 3 , 4 As shown, in a second embodiment of the present invention, the solution includes:

[0056] Based on the first solution described above, the present invention further includes a coating layer 40, which is disposed on the outer periphery of the metal needle 20 to completely enclose the metal needle 20, and the coating layer 40 is made of a biodegradable material.

[0057] By setting the coating layer 40, the strength and rigidity of the metal needle 20 can be increased, thereby increasing the support force of the metal needle 20 and the positioning performance of the metal wire stent 10 when it is placed in the blood vessel. After the positioning stent is placed in the blood vessel, the biodegradable coating layer 40 degrades, causing the connection between the metal needle 20 and the inner wall of the blood vessel to loosen. As a result, when the positioning stent is removed, it is easier to remove and causes less damage to the inner wall of the blood vessel.

[0058] In this embodiment, the maximum diameter of the metal needle 20 can be set to be smaller than the maximum diameter of the support arm 30. Although the smaller diameter of the metal needle 20 will reduce its strength and rigidity, the covering layer 40 can enhance its strength and rigidity to meet the usage requirements. When the covering layer 40 degrades, the lower strength and rigidity of the metal needle 20 will be more prone to bending and its support capacity will be reduced, which will make it easier to remove the positioning bracket and improve its ease of removal.

[0059] This invention achieves efficient positioning and safe use of the positioning stent through the coordinated arrangement of the metal needle 20, the support arm 30, and the bending portion 301. After the metal wire stent 10 is deployed in the blood vessel, the metal needle 20 can penetrate the inner wall of the blood vessel, providing support for the blood vessel and stabilizing the metal wire stent 10 to prevent stent displacement. At the same time, the bending portion 301 on the support arm 30 presses against the inner wall of the blood vessel, further assisting in supporting the blood vessel and reinforcing the position of the metal wire stent 10, while also precisely limiting the insertion depth of the metal needle 20 to prevent damage to the blood vessel due to excessive insertion. This design allows the positioning stent to fully meet positioning requirements while effectively ensuring the safety of clinical use.

[0060] The above description is merely a preferred embodiment of this application. Those skilled in the art should understand that the scope of disclosure in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations 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 application.

Claims

1. An easily removable positioning bracket with a positioning structure, characterized in that, include: A wire scaffold, made of shape memory metal, is used to deploy in a blood vessel; Multiple metal needles, the bottom of which are fixedly connected to the circumferential sidewall of the metal wire support, the top of the metal needles being a free end, the free end being a sharp point, and used to pierce the inner wall of the blood vessel; Multiple support arms are fixedly connected to the circumferential sidewall of the wire support and are respectively connected at an angle to multiple metal needles. A bend is provided at the free end of the support arm, which is formed by extending and bending the support arm. The bend is used to press against the inner wall of the blood vessel. The distance from the bending point of the bent portion to the metal wire support is greater than the distance from the tip of the metal needle to the metal wire support.

2. The easily removable positioning bracket with a positioning structure according to claim 1, characterized in that, It also includes a coating layer, which is disposed on the outer periphery of the metal needle to completely cover the metal needle; The coating is made of a biodegradable material.

3. The easily removable positioning bracket with a positioning structure according to claim 2, characterized in that, The bending point is provided at the farthest end of the bending portion from the metal wire support, and the top of the metal needle is provided with a vertex. The height difference between the bending point and the vertex is in the range of 0.05-0.3mm.

4. The easily removable positioning bracket with a positioning structure according to claim 1, characterized in that, The angle between the centerline of the support arm and the centerline of the wire bracket is in the range of 30°-70°.

5. The easily removable positioning bracket with a positioning structure according to claim 1, characterized in that, The angle between the centerline of the metal needle and the centerline of the metal wire support ranges from 85° to 90°.

6. The easily removable positioning bracket with a positioning structure according to claim 5, characterized in that, When the metal needle is tilted, the tilting direction of the metal needle is consistent with the tilting direction of the support arm.

7. The easily removable positioning bracket with a positioning structure according to claim 2, characterized in that, The maximum diameter of the metal needle is smaller than the maximum diameter of the support arm.

8. The easily removable positioning bracket with a positioning structure according to claim 1, characterized in that, The bending portion is set in a cone shape, and the bending point is the tip of the cone.

9. The easily removable positioning bracket with a positioning structure according to claim 1, characterized in that, The bending portion is set to an arc shape, and the bending portion achieves bending through a curve transition.

10. The easily removable positioning bracket with a positioning structure according to claim 1, characterized in that, The wire support is formed by braiding or spiraling multiple wires made of shape memory metal.

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