Extravascular stent

Abstract

The present invention discloses an extravascular stent, which relates to the field of medical device technology. The extravascular stent includes a first sleeve, a second sleeve, and a third sleeve; the first sleeve is suitable for being sleeved on the periphery of a venous blood vessel, and is provided with a plurality of deformation grooves, the area between two adjacent deformation grooves is hollowed out, and the deformation grooves are used to enable the first sleeve to adapt to changes in the diameter of the venous blood vessel; the second sleeve is connected to one side of the second end of the first sleeve, and the second sleeve is suitable for being sleeved on the periphery of an upstream arterial blood vessel; the third sleeve is connected to the other side of the second end of the first sleeve, and the third sleeve is suitable for being sleeved on the periphery of a downstream arterial blood vessel. The present invention provides an extravascular stent, which improves the structural design, increases the convenience of installing the extravascular stent, reduces the operation time, and increases the adaptability of the extravascular stent to changes in the diameter of the venous blood vessel, and saves material costs and reduces treatment costs.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to an extravascular stent. Background Art

[0002] Autologous arteriovenous fistula is a common way to construct vascular access for patients with end-stage renal disease undergoing hemodialysis treatment. Vascular access is a way to continuously draw blood from the patient's body to the outside of the body and then return it to the body.

[0003] During arteriovenous fistula formation, a vein typically attaches directly to an artery, leading to turbulent blood flow at the anastomosis and dramatic changes in blood pressure and circulation on the venous side. This can cause excessive stress within the vascular walls of the anastomosis and the downstream vein, leading to pathological intimal hypertrophy and sometimes causing blockage and stenosis. To address these issues, existing technologies have proposed placing an extravascular stent at the anastomosis to mitigate the significant blood flow fluctuations in the vein during the initial stages of anastomosis formation.

[0004] Existing Y-shaped extravascular stents consist of an elongated portion positioned around the native vessel and a tubular portion protruding from the side of the elongated portion and positioned around the grafted vessel. The elongated portion is provided with a slit running along the stent's longitudinal direction. However, as arterial blood flows into the vein, the vein's diameter increases. However, the fixed diameter of this extravascular stent cannot adapt to changes in vein diameter, leading to venous hypertension and its associated chain reactions. Furthermore, this extravascular stent requires a large amount of material, resulting in high cost and high treatment costs for patients. Summary of the Invention

[0005] The main purpose of the present invention is to provide an extravascular stent, aiming to improve the adaptability of the extravascular stent to changes in the diameter of venous blood vessels, save material costs, and reduce patient treatment costs.

[0006] To achieve the above-mentioned object, the present invention provides an extravascular stent for supporting an arteriovenous anastomosis, the extravascular stent comprising:

[0007] a first sleeve member adapted to be sleeved around the periphery of a venous vessel, the first sleeve member having a first end remote from the arterial vessel and a second end proximal to the arterial vessel, the first sleeve member being provided with a plurality of deformation grooves extending axially thereof, the region between two adjacent deformation grooves being hollowed out, the deformation grooves being used to enable the first sleeve member to adapt to changes in the diameter of the venous vessel;

[0008] a second sleeve connected to one side of the second end of the first sleeve, the second sleeve being adapted to be sleeved on the periphery of an upstream arterial blood vessel; and

[0009] The third sleeve is connected to the other side of the second end of the first sleeve. The third sleeve is suitable for being sleeved on the periphery of the arterial blood vessel on the downstream side.

[0010] Optionally, the second sleeve member and the third sleeve member are both provided with openings for being sleeved on the periphery of a blood vessel to form a "C"-shaped structure.

[0011] Optionally, at least one of the second sleeve member and the third sleeve member is hollowed out.

[0012] Optionally, the diameter of the first sleeve is smaller than or equal to the diameters of the second sleeve and the third sleeve, and the diameters of the second sleeve and the third sleeve are the same.

[0013] Optionally, the diameter of the first sleeve is larger than the diameters of the second sleeve and the third sleeve, and the diameters of the second sleeve and the third sleeve are the same.

[0014] Optionally, the extravascular stent further includes a connector, and the second sleeve and the third sleeve are connected via the connector.

[0015] Optionally, the connecting member includes a first connecting rod, a second connecting rod and a fixing member, the first connecting rod is connected to the second sleeve member, the second connecting rod is connected to the third sleeve member, and the first connecting rod and the second connecting rod are connected via the fixing member.

[0016] Optionally, the first connecting rod and the second sleeve are integrally formed, and the second connecting rod and the third sleeve are integrally formed.

[0017] Optionally, the first sleeve, the second sleeve and the third sleeve are integrally formed.

[0018] Optionally, the extravascular stent is made by integrally laser cutting a tube and then performing a stretching and shaping process.

[0019] In the technical solution of the present invention, the extravascular stent includes a first sleeve, a second sleeve, and a third sleeve; the first sleeve is suitable for being sleeved around the periphery of a venous vessel, the first sleeve having a first end away from the arterial vessel and a second end close to the arterial vessel, the first sleeve being provided with a plurality of deformation grooves extending along its axial direction, the area between two adjacent deformation grooves being hollowed out, and the deformation grooves being used to enable the first sleeve to adapt to changes in the diameter of the venous vessel; the second sleeve is connected to one side of the second end of the first sleeve, the second sleeve being suitable for being sleeved around the periphery of the upstream arterial vessel; the third sleeve is connected to the other side of the second end of the first sleeve, the third sleeve being suitable for being sleeved around the periphery of the downstream arterial vessel. It can be understood that the present invention provides an extravascular stent with an improved structural design. By providing the deformation grooves and the hollow structure, the adaptability of the extravascular stent to changes in the diameter of the venous vessel is effectively improved, and the material consumption is reduced, thus saving material costs and reducing patient treatment costs. In addition, the extravascular stent of the present invention is provided with an opening, which effectively improves the convenience of installing the extravascular stent and reduces the operation time. The structure of the extravascular stent is stable and reliable, ensuring the stability of the support of the arteriovenous anastomosis. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0021] Figure 1 This is a schematic diagram of the application of an embodiment of the extravascular stent of the present invention;

[0022] Figure 2 This is a schematic structural diagram of an embodiment of an extravascular stent according to the present invention;

[0023] Figure 3 This is a diagram showing the processing of an embodiment of an extravascular stent according to the present invention;

[0024] Figure 4 A diagram showing the processing of another embodiment of the extravascular stent of the present invention;

[0025] Figure 5 This is a front view of another embodiment of the extravascular stent of the present invention;

[0026] Figure 6 This is a schematic structural diagram of another embodiment of the extravascular stent of the present invention.

[0027] Description of Figure Numbers:

[0028] 10. First socket; 20. Second socket; 30. Third socket; 40. Connector; 10a. Deformation groove; 10b. First hollow portion; 100. Vein; 200. Artery; 20a. Opening; 30a. Second hollow portion; 41. First connecting rod; 42. Second connecting rod; 43. Fixing member.

[0029] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without creative work are within the scope of protection of the present invention.

[0031] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0032] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0033] In addition, the descriptions of "first", "second", etc. in the present invention are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. The meaning of "and / or" appearing in the full text is to include three parallel solutions. Taking "A and / or B" as an example, it includes solution A, or solution B, or a solution in which both A and B are satisfied. The technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0034] Autologous arteriovenous fistula is a common way to construct vascular access for patients with end-stage renal disease undergoing hemodialysis treatment. Vascular access is a way to continuously draw blood from the patient's body to the outside of the body and then return it to the body.

[0035] During arteriovenous fistula formation, a vein typically attaches directly to an artery, leading to turbulent blood flow at the anastomosis and dramatic changes in blood pressure and circulation on the venous side. This can cause excessive stress within the vascular walls of the anastomosis and the downstream vein, leading to pathological intimal hypertrophy and sometimes causing blockage and stenosis. To address these issues, existing technologies have proposed placing an extravascular stent at the anastomosis to mitigate the significant blood flow fluctuations in the vein during the initial stages of anastomosis formation.

[0036] Existing Y-shaped extravascular stents consist of an elongated portion positioned around the native vessel and a tubular portion protruding from the side of the elongated portion and positioned around the grafted vessel. The elongated portion is provided with a slit running along the stent's longitudinal direction. However, as arterial blood flows into the vein, the vein's diameter increases. However, the fixed diameter of this extravascular stent cannot adapt to changes in vein diameter, leading to venous hypertension and its associated chain reactions. Furthermore, this extravascular stent requires a large amount of material, resulting in high cost and high treatment costs for patients.

[0037] In addition, existing extravascular stents have complex structures, are inconvenient to install, and are difficult to perform.

[0038] In this regard, the present invention proposes an extravascular stent, aiming to solve the above-mentioned problems existing in the prior art.

[0039] Reference Figure 1 and Figure 2 In one embodiment of the present invention, the extravascular stent is used to support the arteriovenous anastomosis, and the extravascular stent includes a first sleeve 10, a second sleeve 20 and a third sleeve 30; the first sleeve 10 is suitable for being sleeved on the periphery of the vein 100, and the first sleeve 10 has a first end away from the artery 200 and a second end close to the artery 200. The first sleeve 10 is provided with a plurality of deformation grooves 10a extending along its axial direction, and the area between two adjacent deformation grooves 10a is hollowed out, that is, the first sleeve 10 is provided with a plurality of deformation grooves 10a extending along its axial direction. 0 is provided with a plurality of first hollow portions 10b, and the deformation grooves 10a are used to enable the first sleeve 10 to adapt to changes in the diameter of the vein 100. The first hollow portions 10b can further improve the adaptability of the first sleeve 10; the second sleeve 20 is connected to one side of the second end of the first sleeve 10, and the second sleeve 20 is suitable for being sleeved on the periphery of the upstream artery 200; the third sleeve 30 is connected to the other side of the second end of the first sleeve 10, and the third sleeve 30 is suitable for being sleeved on the periphery of the downstream artery 200.

[0040] In this embodiment, the first sleeve 10, the second sleeve 20, and the third sleeve 30 can all be made of polylactic-co-glycolic acid (PLGA). This material can be adjusted to maintain a support period ranging from several months to two years by adjusting the polymer ratio (e.g., the ratio of lactic acid to glycolic acid in the PLGA). Of course, other materials can also be used, and this is not limited here.

[0041] The first sleeve 10, the second sleeve 20, and the third sleeve 30 can be an integrally formed structure. Specifically, the extravascular stent can be manufactured by laser cutting a tube and then stretching and shaping it. Of course, the first sleeve 10, the second sleeve 20, and the third sleeve 30 can also be a separate structure assembled by welding or bonding, etc., which is not limited herein.

[0042] In this embodiment, the notch of the deformation groove 10a is located at the end of the first sleeve 10 away from the end of the artery 200, so that the end has better adaptability. There is at least one deformation groove 10a, and four are shown in the figure. The four deformation grooves 10a can be evenly spaced along the circumference of the first sleeve 10, and the specific length and width are not limited.

[0043] It can be understood that the present invention provides an extravascular stent with improved structural design. By setting the deformation groove 10a and the hollow structure, the adaptability of the extravascular stent to the diameter change of the vein 100 is effectively improved, and the material consumption is less and the weight is lighter, which saves material costs and reduces patient treatment costs.

[0044] In order to further reduce the weight of the extravascular stent, further save material usage and reduce treatment costs, refer to Figures 2 to 4 In some embodiments, at least one of the second sleeve 20 and the third sleeve 30 is hollowed out, such as Figure 2 As shown, the third sleeve 30 is provided with a plurality of second hollow portions 30a.

[0045] In this embodiment, in order to enable the extravascular stent to better adapt to changes in the diameter of the artery 200 , strip grooves similar to or identical to the above-mentioned deformation grooves 10a may be provided at the ends of the second sleeve 20 and the third sleeve 30 .

[0046] In order to facilitate the installation of the extravascular stent at the arteriovenous anastomosis and reduce the operation time, the main reference is Figure 2 In one embodiment, the second sleeve 20 and the third sleeve 30 may be provided with an opening 20a for sleeved around the periphery of the blood vessel to form a "C"-shaped structure.

[0047] The extravascular stent of the present invention is provided with an opening 20a, which effectively improves the convenience of installing the extravascular stent and reduces the operation time. In addition, the structure of the extravascular stent is stable and reliable, ensuring the stability of the support of the arteriovenous anastomosis.

[0048] During the operation, the operator can first place the first connector 10 on the vein 100 (at this time, the vein 100 has a cut), make an incision on the artery 200, and then suture one end of the vein 100 to the incision of the artery 200. Then, the second connector 20 and the third connector 30 are placed on the upstream and downstream peripheries of the artery 200 respectively, thus completing the installation of the entire extravascular stent.

[0049] In one embodiment, if Figure 3 As shown, the diameter of the first sleeve 10 is smaller than or equal to the diameters of the second sleeve 20 and the third sleeve 30, and the diameters of the second sleeve 20 and the third sleeve 30 are the same. In this way, the support requirements of the arteriovenous anastomosis can be met when the diameter of the vein 100 is smaller than or equal to the diameter of the artery 200.

[0050] In another embodiment, Figure 4 As shown, the diameter of the first sleeve 10 is larger than the diameters of the second sleeve 20 and the third sleeve 30, and the diameters of the second sleeve 20 and the third sleeve 30 are the same. In this way, the support requirements of the arteriovenous anastomosis can be met when the diameter of the vein 100 is larger than the diameter of the artery 200.

[0051] In order to further improve the support stability of the extravascular stent, refer to Figure 5 and Figure 6 In another embodiment, the extravascular stent may further include a connector 40 , and the second sleeve 20 and the third sleeve 30 are connected via the connector 40 .

[0052] To facilitate processing and assembly of various components, in this embodiment, the connecting member 40 may include a first connecting rod 41, a second connecting rod 42, and a fixing member 43. The first connecting rod 41 is connected to the second socket 20, the second connecting rod 42 is connected to the third socket 30, and the first connecting rod 41 and the second connecting rod 42 are connected by the fixing member 43. The fixing member 43 may be a circular sleeve structure, with both ends of the fixing member 43 respectively sleeved on the first connecting rod 41 and the second connecting rod 42 and fixed by means of threaded connection or welding to connect the first connecting rod 41 and the second connecting rod 42 together.

[0053] In this embodiment, the first connecting rod 41 can be integrally formed with the second sleeve 20, and the second connecting rod 42 can be integrally formed with the third sleeve 30. This arrangement can further improve the overall reliability of the extravascular stent, while also reducing the number of parts and making assembly more convenient.

[0054] Of course, in some other embodiments, the first connecting rod 41 and the second sleeve 20 may also be independent components, and the two are connected by welding or bonding; similarly, the second connecting rod 42 and the third sleeve 30 may also be independent components, and the two are connected by welding or bonding.

[0055] The above descriptions are merely optional embodiments of the present invention and do not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present description and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. An extravascular stent, used for supporting an arteriovenous anastomosis, characterized in that: The extravascular stent comprises: a first sleeve member adapted to be sleeved around the periphery of a venous vessel, the first sleeve member having a first end remote from the arterial vessel and a second end proximal to the arterial vessel, the first sleeve member being provided with a plurality of deformation grooves extending axially thereof, the notches of the deformation grooves being located at the end of the first sleeve member remote from the arterial vessel, and the area between two adjacent deformation grooves being hollowed out, the deformation grooves and the first hollow portion being configured to enable the first sleeve member to adapt to dynamic changes in the diameter of the venous vessel; a second sleeve connecting piece connected to one side of the second end of the first sleeve connecting piece, wherein the second sleeve connecting piece is adapted to be sleeved on the periphery of the upstream arterial blood vessel; a third sleeve connected to the other side of the second end of the first sleeve, wherein the third sleeve is adapted to be sleeved on the periphery of the downstream arterial blood vessel; The diameter of the first sleeve is larger than the diameters of the second sleeve and the third sleeve, and the diameters of the second sleeve and the third sleeve are the same; and A connecting piece, the second socket and the third socket are connected by the connecting piece; the connecting piece includes a first connecting rod, a second connecting rod and a fixing piece, the first connecting rod is connected to the second socket, the second connecting rod is connected to the third socket, and the first connecting rod and the second connecting rod are connected by the fixing piece.

2. The extravascular stent according to claim 1, wherein: The second sleeve member and the third sleeve member are both provided with openings for being sleeved on the periphery of a blood vessel to form a "C"-shaped structure.

3. The extravascular stent according to claim 1 or 2, wherein: At least one of the second sleeve connecting piece and the third sleeve connecting piece is hollowed out.

4. The extravascular stent according to claim 1, wherein: The first connecting rod and the second sleeve are integrally formed, and the second connecting rod and the third sleeve are integrally formed.

5. The extravascular stent according to claim 1, wherein: The first sleeve connecting piece, the second sleeve connecting piece and the third sleeve connecting piece are integrally formed.

6. The extravascular stent according to claim 5, wherein: The extravascular stent is made by laser cutting a tube as a whole and then stretching and shaping it.

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