CN117045408A - Support frame - Google Patents

Abstract

The invention provides a bracket, which comprises a plurality of braiding wires; at least part of the filament bodies of at least two knitting filaments are jointed along the axial direction of the knitting filaments, so that at least one groove is formed on the outer surfaces of the at least two knitting filaments jointed mutually. The invention uses the gap formed by the jointing of the knitting yarns as the groove to bear the medicine, and the groove is not required to be arranged alone, so the process is simple and convenient. Compared with the mode of coating the surface of the woven wire with the medicine, the invention can avoid the problems of medicine falling and particle increase caused by scratch and impact during transportation by using the groove to carry medicine, thereby realizing the problem of reducing the risk of medicine falling in the transportation process of the bracket. And the grooves are in a shape with wide upper part and narrow lower part, so that the effect of rapid front and slow rear parts can be achieved in the drug release process, complications possibly generated after the stent is placed can be quickly released in the initial stage, and the treatment time of the drug can be prolonged by slow release in the later stage. Meanwhile, compared with a metal cutting bracket, the bracket has better flexibility and adherence.

Description

Bracket

Technical field

The present invention relates to the technical field of medical devices, and in particular to a stent.

Background technique

Cardiovascular and cerebrovascular diseases are important diseases that affect human health. Currently, stents for cardiovascular and cerebrovascular diseases are mainly drug-eluting stents (DES). Large-scale randomized, double-blind clinical trials have shown that drug-eluting stents can significantly reduce the occurrence of in-stent restenosis (RS) and major adverse cardiac events (Major Adverse Cardiovascular Events, MACE).

At present, most drug stents are coated with drugs on their inner and outer metal surfaces. This not only results in a high concentration of drugs in blood vessels and a too fast release rate, but also fails to effectively control the release direction of drugs, resulting in some drugs not being absorbed by the blood vessel wall. In addition, the drug coating applied to the position where the shape of the stent changes greatly can easily fall off during the pushing and expansion process of the stent. The shed coating pieces will flow with the blood and easily form thrombus, causing harm to the human body. In this regard, there are some metal-cut stents on the market that use grooves on the wave rods to load drugs, which reduces the risk of drug falling off during the delivery process of the stent, improves the safety and effectiveness of the stent, and at the same time reduces the cost of the stent. risk of internal restenosis and late thrombosis.

Compared with metal cutting stents, braided stents have better flexibility and adhesion, are especially suitable for small and tortuous intracranial blood vessels, and have a wider range of applications. However, because the braided wire of the braided stent is too thin, it is impossible to use grooves to load the drug. The only way to load the drug is to coat the surface of the braided wire, which cannot solve the problem of drug falling off and the increase of particles caused by scratches and impacts during transportation. .

Contents of the invention

The object of the present invention is to provide a stent to solve the problem of how to reduce the risk of drug falling off during the delivery process of the braided stent.

In order to solve the above technical problems, the present invention provides a stent, which includes a plurality of braided wires; wherein, along the axial direction of the braided wires, at least part of the filament bodies of at least two of the braided wires are in contact with each other, so that when they are in contact with each other, At least one groove is formed on the outer surface of at least two of the combined braided wires.

Optionally, in the stent, the groove extends along the axial direction of the braided wire; and in the cross-section of the groove, the width of the groove extends along the edge close to the at least two braided wires. The silk is tapered in the direction of the joint.

Optionally, in the stent, at least one of the grooves contains medicine, and the groove containing the medicine is located on the inner wall of the stent and/or the outer wall of the stent.

Optionally, in the stent, the at least two braided wires are thermally set to fit together.

Optionally, in the stent, the at least two braided wires are adhered together through adhesion; wherein a partial area of at least one of the grooves is filled with adhesive.

Optionally, in the stent, the viscose intervals are arranged in the groove; wherein, along the axial direction of the braided wire, the length range of the intervals is 10 times the length of the braided wire. %-40%; and/or, the total length of all the viscose in the groove is 1%-10% of the length of the braided wire.

Optionally, in the stent, two of the braided wires fit together along the axial direction of the braided wires to form two of the grooves on the outer surfaces of the two braided wires; Medicine is accommodated in all of the grooves, or medicine is accommodated in one of the grooves.

Optionally, in the stent, the material of the braided wire includes cobalt-based alloy, platinum-iridium alloy, platinum, platinum-tungsten alloy, silver alloy, aluminum alloy, copper alloy, stainless steel, nickel-titanium alloy, active ceramics and At least one type of carbon.

Optionally, in the stent, at least two of the braided wires that are attached to each other are made of the same or different materials.

Optionally, in the stent, the cross-sectional shape of the braided wire is at least one of a circle, an ellipse, or a polygon.

Optionally, in the stent, the stent has a mesh structure and is woven from at least one set of the braided wires that fit together, or is made from at least one set of the braided wires that fit together. At least one single braided wire is woven.

Optionally, in the stent, at least one end of the stent is in a flared shape; and the braided wires located at the end are knitted back into an arc shape, and/or adjacent The bare ends of the braided wires are connected in pairs.

To sum up, the present invention provides a stent that includes a plurality of braided wires; wherein, along the axial direction of the braided wires, at least part of the filament bodies of at least two of the braided wires are in contact with each other, so that when they are in contact with each other, At least one groove is formed on the outer surface of at least two of the braided wires. The present invention uses the gaps formed by the braided wires as grooves to carry the medicine. There is no need to set up separate grooves, and the process is simple. Moreover, compared with the method of loading drugs on the surface of braided wires, the present invention uses grooves to load drugs, which can avoid the problems of drug falling off and the increase of particles caused by scratches and impacts during transportation, and reduces the drug falling off during the transportation process of the stent. risk, improving the effectiveness and safety of the stent during operation and use, while solving the problems of in-stent restenosis and late thrombosis. At the same time, because the groove is wide at the top and narrow at the bottom, it can achieve the effect of fast at the front and slow at the back during the release process of the drug. The rapid release in the early stage can treat the complications that may occur after the placement of the stent, and the slow release in the later stage can extend the treatment time of the drug. In addition, compared with metal cutting brackets, the bracket provided by the present invention has better flexibility and wall adhesion.

Description of the drawings

Figure 1 is a partial structural schematic diagram of a stent in an embodiment of the present invention;

Figure 2 is a schematic diagram of the position of the groove in the embodiment of the present invention;

Figure 3 is a schematic diagram of the position of the groove in the embodiment of the present invention;

Figure 4 is a schematic diagram of the position of the groove in the embodiment of the present invention;

Figure 5 is a schematic diagram of the position of the groove in the embodiment of the present invention;

Figure 6 is a schematic diagram of the distribution of drugs in an embodiment of the present invention;

Figure 7 is a schematic diagram of the distribution of drugs in an embodiment of the present invention;

Figure 8 is a schematic diagram of the distribution of viscose in an embodiment of the present invention;

Figure 9 is a schematic diagram of the distribution of viscose and drugs in an embodiment of the present invention;

Figure 10 is a schematic diagram of the distribution of viscose and drugs in the embodiment of the present invention;

Figure 11 is a schematic diagram of the distribution of viscose and drugs in the embodiment of the present invention;

Figure 12 is a schematic structural diagram of a stent in an embodiment of the present invention;

Among them, the description of the reference signs is:

10-stent; 10a-distal part; 10b-middle part; 10c-proximal part; 100-braided wire; 101-development sleeve;

M-drug; G-glue; T-groove.

Detailed ways

In order to make the purpose, advantages and features of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are in a very simplified form and are not drawn to scale, and are only used to conveniently and clearly assist in explaining the embodiments of the present invention. In addition, the structures shown in the drawings are often part of the actual structure. In particular, each drawing needs to display different emphasis, and sometimes uses different proportions. It should also be understood that, unless otherwise specified or pointed out, the terms "first", "second", "third" and other descriptions in the specification are only used to distinguish various components, elements, steps, etc. in the specification, rather than Used to express the logical relationship or sequential relationship between various components, elements, steps, etc.

The definitions of "proximal" and "distal" in this article are: "distal" usually refers to the end of the medical device that first enters the patient's body during normal operation, and "proximal" usually refers to the end of the medical device that enters the patient's body during normal operation. The end closest to the operator during the process.

Currently, stent drug-loading methods include full-surface coating, single-sided drug coating, trench coating, etc. However, the coating method of coating on the surface of the stent is not suitable for microcatheter delivery. Because scratches are easy to occur during transportation, resulting in a reduction in drug dosage and an increase in particles. The form of grooving is suitable for laser cutting brackets because the cut wall thickness and shape are uniform and easy to achieve grooving. The stents delivered by braided self-elastic microcatheters do not have a good drug-loading form.

In this regard, this embodiment provides a bracket. Referring to Figures 1 and 2, the stent includes a plurality of braided wires 100; wherein, along the axial direction of the braided wires 100, at least part of the filament bodies of at least two braided wires 100 are attached to each other, so that when they are attached together, At least one groove T is formed on the outer surface of at least two braided wires 100 . It can be seen that the stent provided in this embodiment uses the at least two braided wires 100 that fit together to form a natural groove T, which solves the previous engineering contradiction and overcomes the technical problem of drug loading in the groove of the braided stent. At the same time, it solves the problem of the combination of the coating and the stent, improves the effectiveness and safety of the drug stent during operation, and solves the problems of restenosis and late thrombosis in the stent. At the same time, compared with the metal cutting bracket, the bracket provided in this embodiment has better flexibility and wall adhesion.

The bracket provided in this embodiment will be introduced in detail below with reference to Figures 1-12.

Please refer to Figures 1-2. The stent provided in this embodiment is woven from a plurality of braided wires 100, and has better flexibility and wall adhesion than the woven stent. Wherein, along the axial direction of the braided wires, at least part of the filament bodies of at least two braided wires 100 are in contact with each other to form at least one groove on the outer surface of the at least two braided wires 100 that are in contact with each other. T. It can be understood that among all the braiding wires 100 used to weave the stent, at least some of the braiding wires 100 are in contact with each other, or three, four, five, etc., are in contact with each other. The fitting methods include but are not limited to side by side fitting, combination in a circular shape, combination in a triangular shape, or combination in a rectangular shape. Moreover, the bonding form of the braided yarn 100 may be that the entire yarn body is bonded together, or part of the yarn body is bonded together and part of the yarn body is separated.

In view of the cross-sectional shape of the braided wire 100, a gap is formed where the wire body of the braided wire 100 is in contact, and the gap is the groove T shown in FIG. 2. The groove T extends along the axial direction of the braided wire 100 and is used to carry medicine. In this embodiment, the cross-sectional shape of the braided wire 100 is circular. In other embodiments, as shown in FIGS. 3-5 , the cross-sectional shape of the braided wire 100 may also be an ellipse, a polygon, or the like. For example, the cross-section of the braided wire 100 shown in Figure 3 is an ellipse; the cross-section of the braided wire 100 shown in Figure 4 is square; and the cross-section of the braided wire 100 shown in Figure 5 is a pentagon. Therefore, different cross-sectional shapes of the braided wire 100 result in different bonding areas, and thus the number and volume of the grooves T formed are different. Among them, two grooves T are formed in Figures 2-4, and one groove T is formed in Figure 5. When three or four equal braided wires 100 are attached, three or four equal grooves may be formed. T. Furthermore, the braided wires 100 with different shapes of cross-sections can be selected according to the needs of drug loading, which is not limited in this embodiment.

It can be understood that this embodiment circumvents the technical difficulty of making grooves on the braided wires 100 by fitting the braided wires 100 together, and using the gaps formed by the joining as grooves T for carrying drugs. Therefore, the stent provided in this embodiment can achieve drug loading in the grooves without the need for separate grooves, thereby avoiding the problems of drug falling off and increasing particles due to scratches and impacts during transportation, and reducing the drug falling off during the transportation process of the stent. risks of.

Referring to FIGS. 2-5 , from a cross-section view of the groove T, the width of the groove T tapers in a direction close to the joint of the at least two braided wires 100 . That is, the cross section of the groove T is similar to a triangle or an inverted triangle, that is, a shape with a wide upper side and a narrow lower side, where the upper side refers to a position away from the joint of the at least two braided wires 100, and the lower side is close to The position where the at least two braided wires 100 meet. Since the groove T is wide at the top and narrow at the bottom, it can achieve the effect of fast in the front and slow in the back during the release process of the drug. The rapid release in the early stage can treat the complications that may occur after the placement of the stent, and the slow release in the later stage can extend the treatment of the drug. time.

Further, at least one of all the grooves T formed by the at least two braided wires 100 contains the medicine M. In other words, the drug M is accommodated in all the grooves T, or the drug M is accommodated in one of the grooves T, or the drug M is accommodated in two of the grooves T. Moreover, the drug M may cover the entire area or part of the groove T. This embodiment will be specifically described by taking the two braided wires 100 to form two grooves T as an example. Referring to FIGS. 2 and 6 , the filament bodies of the two braided wires 100 are in contact with each other to form two grooves T on the outer surfaces of the two braided wires 100 . According to the need to carry the amount of medicine, both of the two grooves T may contain the medicine M, or one of the grooves T may contain the medicine M. As shown in FIG. 6 , the drug M fills the groove T completely. Wherein, the cross section of the braided wire 100 is circular, then the volume of the groove T is: (4-π)*(r ² L)/2; r is the radius of the braided wire 100, and L is Depending on the axial length of the braided wire 100, usually the drug loading amount of one groove is 10 micrograms to 150 micrograms. Alternatively, as shown in FIG. 7 , some areas of the groove T are filled with the drug M, and some areas are not filled with the drug M.

Furthermore, in order to ensure the diffusion of drugs, part of the grooves T on the inner wall of the stent 10 can be selected to carry the drug, or part of the grooves T on the outer wall of the stent 10 can be selected to carry the drug, or the stent Parts of the grooves T on the inner wall and outer wall of 10 are loaded with medicine.

Furthermore, the at least two braided wires 100 are thermally set to fit together, that is, there is no gap between the at least two braided wires 100 and are closely connected after being heated and set to prevent the leakage of the medicine M. In order to further strengthen the connection between the at least two braided wires 100, adhesive can also be used to achieve adhesion between the at least two braided wires 100. As shown in Figures 8-11, at least a partial area of the groove T contains adhesive G. In one embodiment, the at least two braided wires 100 are formed with more than two grooves T. For example, if two grooves T are formed in the fitting method shown in Figures 2 and 8, one of the grooves T may contain the medicine M, and the other groove T may contain adhesive. G. It can be understood that the groove T on one side shown in Figures 6 and 7 contains medicine M, and the side shown in Figure 8 contains adhesive G. In another embodiment, the groove containing the adhesive G also contains the drug M, as shown in Figure 9, to achieve better control of the distribution and dosage of the drug M, and If multiple drugs M are filled, they can be separated by the adhesive G.

Please continue to refer to Figures 8-11. The adhesive G is arranged in the groove T at intervals. Wherein, in the axial direction of the braided wire 100, the length range of the interval is 10%-40% of the length of the braided wire 100, optionally: 10%, 20%, 30% or 40%; And/or, the total length of all the viscose G in the groove T is 1%-10% of the length of the braided wire 100, optionally: 1%, 5% or 10%. Optionally, the adhesive G is set by dispensing glue. Further, as shown in Figures 8 and 9, the adhesives G are arranged at equal intervals, or the intervals between the adhesives G are unequal. Alternatively, as shown in FIG. 10 , the viscose G is disposed at opposite ends of the braided wire 100 , and the medicine M is disposed at the middle section of the braided wire 100 . Or, as shown in FIG. 11 , the viscose G is disposed at the middle section of the braided wire 100 , and the medicine M is disposed at the opposite ends of the braided wire 100 .

In some embodiments, the braided wire 100 is made of cobalt-based alloys, platinum-iridium alloys, platinum, platinum-tungsten alloys, silver alloys, aluminum alloys, copper alloys, stainless steel, nickel-titanium alloys, active ceramics and carbon. At least one. Because different materials can bring out the advantages of different materials, for example: stainless steel materials have better corrosion resistance, higher strength, and lower cost; nickel-titanium alloy materials, shape memory alloys, better elasticity, and strong plasticity; and cobalt-based alloy materials Better mechanical properties and corrosion resistance. Therefore, the materials of at least two braided wires 100 that are attached together are the same or different. For example, the material of the at least two braided wires 100 that are attached together is nickel-titanium alloy. After heat setting, the at least two nickel-titanium alloy braided wires 100 have a shape memory function and are less likely to separate, thereby preventing leakage of the medicine M. Alternatively, some of the at least two braided wires 100 that are attached together are made of stainless steel, and some of the braided wires are made of nickel-titanium alloy. Or, among the at least two braided wires 100 that are attached together, some of the braided wires 100 are made of cobalt-based alloy, and some of the braided wires are made of nickel-titanium alloy. Alternatively, among the plurality of braided wires woven into the stent 10 , some of the braided wires 100 are made of nickel-titanium alloy, and some of the braided wires 100 are made of cobalt-based alloy. In this embodiment, the material of the braided wire 100 is not specifically limited.

Please refer to Figure 12. The stent 10 has a mesh structure, and at least two of the braided wires 100 that are in contact with each other form a set of braided wires. Then the stent 10 is woven from at least one set of braided wires, or is made of At least one group of braided wires and at least one single braided wire 100 are braided together. In other words, in one embodiment, the braided wires 100 woven into the stent 10 are adhered to each other in pairs or in plurality. For example, the stent 10 uses 64 braided wires 100 . Every two braided wires 100 are joined together to form a group of braided wires, and the stent 10 is woven from 32 groups of braided wires joined in pairs. In another embodiment, parts of the braided wires 100 woven into the stent 10 are attached in pairs or in plurality, and the remaining part is a single braided wire 100 . For example, the stent 10 uses 48 braided wires 100 . Among the 30 braided wires, every two braided wires 100 are bonded together to form 15 groups of braided wires that are bonded in pairs. The remaining 18 braided wires 100 and the 15 groups of braided wires that fit in pairs are braided together to form the stent 10 .

Further, the stent 10 includes a distal end portion 10a, a middle portion 10b and a proximal end portion 10c that are connected in sequence. At least one end of the distal end portion 10a and the proximal end portion 10c is in a flared shape, that is, the distal end portion 10a and/or the proximal end portion 10c has a flaring shape in a direction away from the middle portion 10b. The radial dimensions are increased to increase the anchorage of the stent 10 . In order to reduce damage to the vascular endothelium by the end of the braided wire 100, the distal end 10a and the proximal end 10c have a closed structure. The closed structure may be an arc-shaped structure formed by braiding back the braided yarn 100 . As shown in the distal part 10a in Figure 12, the braided wire 100 woven to the end of the stent 10 is folded into a smooth arc shape and continues to be woven in the opposite direction to avoid puncturing the blood vessel wall. The closed structure may also be the structure of the proximal end 10c as shown in Figure 12, that is, after the braided wires 100 are braided to the end, the bare ends of the adjacent braided wires 100 are connected in pairs. Optionally, an adhesive or welding connection method is used to fix the extended free end of the braided wire 100, which can also avoid puncturing the blood vessel wall. This embodiment does not limit the specific shapes of the distal part 10a and the proximal part 10c. As shown in Figure 12, one end can be knitted and the other end can be connected, or both ends can be knitted. The knitting method, or the connecting method is used, or the bare ends of the braided wires 100 at each end can be knitted back, and the bare ends of some of the braided wires 100 can be connected. In addition, in order to further protect the blood vessel wall, a developing sleeve 101 can be placed at the bare end connection of each braided wire 100, which can also improve the developing effect of the stent 10. In some other embodiments, at least one end of the bracket 10 may have an unclosed flared structure.

To sum up, this embodiment provides a stent 10 that includes a plurality of braided wires 100; wherein, along the axial direction of the braided wires 100, at least part of the filament bodies of at least two braided wires 100 are in contact with each other, so as to At least one groove T is formed on the outer surface of the at least two braided wires 100 that are in contact with each other. In this embodiment, the braided wires 100 are bonded together, and the gap formed by the bonding is used as a groove T for carrying the medicine. There is no need to separately set the groove T, and the process is simple. Moreover, compared with the method of loading drugs on the surface of the braided wire 100, this embodiment uses grooves to load drugs, which can avoid the problems of drug falling off and the increase of particles due to scratches and impacts during transportation, and reduces the problem of the stent 10 during the transportation process. The risk of Chinese medicine falling off improves the effectiveness and safety of the stent 10 during operation and use, and simultaneously solves the problems of restenosis and late thrombosis in the stent 10 . At the same time, because the groove T is wide at the top and narrow at the bottom, it can achieve the effect of fast in the front and slow in the back during the release process of the drug. The rapid release in the early stage can treat the complications that may occur after placing the stent for 10 years, and the slow release in the later stage can extend the treatment of the drug. time. In addition, compared with metal cutting brackets, the bracket 10 provided in this embodiment has better flexibility and wall adhesion.

In addition, it should be recognized that although the present invention has been disclosed above in preferred embodiments, the above embodiments are not intended to limit the present invention. For any person familiar with the art, without departing from the scope of the technical solution of the present invention, they can use the technical content disclosed above to make many possible changes and modifications to the technical solution of the present invention, or modify it into equivalent changes. Example. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of protection of the technical solution of the present invention.

Claims (12)

1. A stent characterized by comprising a plurality of braided wires; at least part of the filament bodies of at least two braiding filaments are attached to each other along the axial direction of the braiding filaments, so that at least one groove is formed on the outer surfaces of the attached at least two braiding filaments.

2. The stent of claim 1, wherein the grooves extend in an axial direction of the braided wires; and on the cross section of the groove, the width of the groove is gradually reduced along the direction close to the joint of the at least two braiding wires.

3. The stent of claim 1, wherein at least one of the grooves contains a drug and the groove containing a drug is located on an inner wall of the stent and/or an outer wall of the stent.

4. The stent of claim 1, wherein the at least two braided filaments are heat-set to conform to one another.

5. The stent of claim 1, wherein the at least two braided filaments are bonded together; wherein, at least one partial area in the groove contains viscose.

6. The bracket of claim 5, wherein the adhesive is disposed in the recess at intervals; wherein, along the axial direction of the braided wire, the length of the interval ranges from 10% to 40% of the length of the braided wire; and/or the total length of all the viscose in the grooves is 1% -10% of the length of the braided filaments.

7. The stent of claim 1, wherein two of said braided wires are attached to each other in an axial direction of said braided wires to form two of said grooves in an outer surface of said two braided wires; the two grooves are respectively provided with a medicament, or one of the grooves is provided with a medicament.

8. The stent of claim 1, wherein the braided wire comprises at least one of cobalt-based alloy, platinum iridium alloy, platinum tungsten alloy, silver alloy, aluminum alloy, copper alloy, stainless steel, nickel titanium alloy, reactive ceramics, and carbon.

9. The stent of claim 1, wherein at least two of the braided filaments that are in contact are the same or different.

10. The stent of claim 1, wherein the cross-sectional shape of the braided wires is at least one of circular, elliptical, or polygonal.

11. The stent of claim 1, wherein the stent is a mesh structure and is woven from at least one set of the braided filaments that are bonded or from at least one set of the braided filaments that are bonded and at least one single braided filament.

12. The stent of claim 1, wherein at least one end of the stent is flared; and the braiding wires positioned at the end parts are in a circular arc shape after being braided back, and/or the bare ends of the adjacent braiding wires are connected in pairs.