CN216168086U

CN216168086U - Braided stent and braided stent system

Info

Publication number: CN216168086U
Application number: CN202122688665.4U
Authority: CN
Inventors: 不公告发明人
Original assignee: Shanghai Bochang Medical Technology Co ltd
Current assignee: Shanghai Bochang Medical Technology Co ltd
Priority date: 2021-11-04
Filing date: 2021-11-04
Publication date: 2022-04-05
Anticipated expiration: 2031-11-04

Abstract

The utility model provides a braided stent and a braided stent system, wherein the braided stent is formed by cross-braiding at least one braided wire, one or more grooves are formed in the surface of at least part of the braided wire, a drug coating is coated in at least part of the grooves, the braided stent system comprises a delivery tube sheath, a pushing guide wire and the delivery tube sheath, and the pushing guide wire and the delivery tube sheath are accommodated in the delivery tube sheath. According to the utility model, the grooves coated with the drug coating are arranged on the surface of the braided wire of the braided stent, so that the drug storage capacity and the drug storage quantity of the braided stent are improved, and the accidental falling of the drug coating in the delivery of the braided stent is avoided.

Description

Braided stent and braided stent system

Technical Field

The utility model relates to the technical field of medical instruments, in particular to a braided stent and a braided stent system.

Background

Intracranial aneurysms are mostly abnormal bulges on the wall of an intracranial artery, are the first causes of subarachnoid hemorrhage, and are second only to cerebral thrombosis and hypertensive cerebral hemorrhage in cerebrovascular diseases and are the third cause. For some complicated aneurysms (such as large aneurysms, wide-neck aneurysms, fusiform and sandwich aneurysms and the like), intravascular braided stents are mostly adopted for treatment, the stents are utilized to interfere blood flow entering the aneurysms from parent arteries, so that blood in the aneurysms is blocked and deposited, thrombosis in the aneurysms is caused, and the aneurysms is further promoted to be completely blocked, and the stents can form a 'scaffold' for the climbing growth of vascular endothelial cells, so that the endothelialization of neck mouths of the aneurysms is promoted, and the aneurysms are prevented from being broken. When the intravascular braided stent is used for improving the cure rate of the existing refractory large aneurysm and various complex aneurysms, complications, especially ischemic complications, also exist, but in order to reduce the risk of the ischemic complications, double-resistance is adopted, and the risk of bleeding complications is increased. Therefore, the stent is usually provided with an antithrombotic drug to reduce the risk of ischemic complications.

Similar to the concept of reducing ischemic complications, in the treatment of ischemic vascular diseases such as intravascular stenosis, drug stents are also used to prevent ischemic complications such as restenosis, as disclosed in U.S. patent application No. 20090132031a1, in which an anti-stenosis drug is loaded in the lumen (central lumen) of the shaft of a spring stent and in the through-holes (channels) connecting the lumen to the outside, the lumen and the through-holes of the stent shaft are cut from the surface to the center of the shaft by a laser, and the stent is delivered to the site of a stenotic lesion by a balloon. However, the stent is used for a narrow part, a certain radial supporting force is required to prevent the stent from shifting, and the inner cavity and through hole structures on the rod are realized by laser cutting, so that the rod is required to have a larger diameter, laser grooving is realized, and a certain radial supporting force is still provided under the condition of having the hollow inner cavity and the through hole structures; in addition, at present, most of medicine stents used for intravascular stenosis are formed by digging grooves with the depth of dozens of microns on a laser engraving stent through laser to carry anti-stenosis medicines, compared with a woven stent, the laser engraving stent has poor flexibility and stent adherence, ischemic complications are easier to occur, and the laser engraving stent is difficult to balance the relationship between the flexibility adherence and the blood flow guiding effect.

At present, most of intravascular stents for treating complex aneurysms are woven stents, the woven stents need to have larger mesh density (namely, the number of meshes in a unit area) to achieve the function of guiding blood flow and good adherence and radial supporting force, so that woven braided wires are required to be thinner, and the woven stents are mainly characterized in that the surfaces of the metal braided wires of the stents are treated and grafted with phosphorylcholine coatings or hydrophilic coatings to reduce the risk of thrombus in the stents. The outer surface of the braided wire is coated with the drug coating, the braided wire is fine, the surface area of the coating is limited, namely the coating content on the surface of a single stent is also limited, and the coating is only coated on the surface of the braided wire of the stent, so that the drug release is fast, and the drug is difficult to match with the proliferation curve of smooth muscle cells in blood vessels so as to achieve the optimal anti-proliferation effect; in addition, the existing coating process is complex, the coating is very easy to be uneven to influence the anticoagulation effect, and the coated coating is very easy to be adhered or caked among fine meshes or weaving wire cross points on the woven stent, so that the adhered or caked coating falls off in the stent conveying and expanding process to block intracranial far-end blood vessels.

SUMMERY OF THE UTILITY MODEL

In view of the problems in the prior art, an object of the present invention is to provide a braided stent and a braided stent system, in which a groove for accommodating a drug is formed on the surface of a braided wire of the braided stent, so as to improve the drug storage capacity of the braided stent and prevent the drug coating from accidentally dropping off during the delivery of the braided stent.

The embodiment of the utility model provides a braided stent, which is formed by cross-braiding at least one braided wire, wherein one or more grooves are formed in the surface of at least part of the braided wire, and a medicine coating is coated in at least part of the grooves.

In some embodiments, the grooves extend in the direction of extension of the braided wire, or the grooves are dimples distributed over the surface of the braided wire.

In some embodiments, the groove has a shape of a sector, an ellipse, or a polygon in a cross section of the braided wire.

In some embodiments, the braided wire has a radial dimension of 15 μm to 150 μm.

In some embodiments, the braided wire has a radial dimension of 15 μm to 60 μm.

In some embodiments, in a cross section of the braided wire, an area of the groove is 3% to 40% of a cross sectional area of the braided wire when the groove is not provided.

In some embodiments, the braided wire is formed by a first braided wire and a second braided wire wound helically around the outside of the first braided wire, forming a helical spring structure encircling the first braided wire.

In some embodiments, the gap of the helical spring structure is the groove, or a surface of the first and/or second braided wire is provided with the groove.

In some embodiments, the second woven wire is a developable wire.

The utility model also provides a braided stent system which comprises a delivery tube sheath, a pushing guide wire and the braided stent, wherein the braided stent is loaded at the distal end of the pushing guide wire, and the delivery tube sheath is used for accommodating the pushing guide wire and the braided stent.

The braided stent and the braided stent system provided by the utility model have the following advantages:

(1) the utility model provides a braided stent formed by cross-braiding braided wires and a braided stent system comprising the braided stent.

(2) Furthermore, in the conveying process of the woven stent, the medicine in the groove can be released from outside to inside, a certain release period is provided, and a curve of the medicine release amount changing along with time can be designed according to the cycle of thrombus formation in blood vessels so as to achieve the best curative effect.

(3) Furthermore, because the medicine coating is accommodated in the groove of the knitting wire, the medicine coating can not be adhered or caked at the cross part between meshes or knitting wire due to the small meshes of the knitting stent, and further the problems of blood vessel embolism and the like caused by falling off in the conveying process due to the adhesion or caked of the medicine coating can be avoided. Meanwhile, most of the medicine is not on the surface of the braided stent, so that the medicine coating cannot fall off even if slippage between braided wires occurs or friction occurs between the outer surface of the braided stent and the inner surface of a delivery sheath in the process of releasing the medicine along with delivery of the braided stent, and the effectiveness of an integral product formed by the braided stent and the medicine is improved;

(4) the braided stents and braided stent systems of the present invention may be used not only to treat intracranial aneurysms, but also to treat aneurysms at other locations in the body, as well as to treat other types of vascular disease.

Drawings

Other features, objects and advantages of the present invention will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, with reference to the accompanying drawings.

FIG. 1 is a schematic structural view of a braided stent system according to a first embodiment of the utility model;

FIG. 2 is a schematic structural view of a braided stent according to a first embodiment of the utility model;

FIGS. 3 to 5 are schematic cross-sectional views of a braided wire with grooves of three shapes according to a first embodiment of the present invention;

FIG. 6 is a schematic illustration of the calculated cross-sectional area of the first embodiment of the present invention;

fig. 7 is a structural view of a braided wire of a braided stent of a second embodiment of the present invention.

Reference numerals:

10 braided stent system 141 braided wire

11 delivery sheath 141a first braided wire

12 push wire 141b second braided wire

13 developer ring 142 groove

14 weaving support 15 developing spring

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their repetitive description will be omitted. In the specification, "or" may mean "and" or ". The term distal in the present invention is used in relation to proximal, meaning the end closer to the operator than distal, and distal meaning the end further away from the operator than proximal. The "radial dimension" in the present invention means a distance between the farthest two points on the cross section, and the radial dimension of the braided wire is the diameter of the braided wire, taking the cross section of the braided wire as a circle as an example.

The utility model provides a braided stent which is formed by cross-braiding at least one braided wire, wherein one or more grooves are formed in the surface of at least part of the braided wire, and a drug coating is coated in at least part of the grooves, so that the drug storage capacity and the drug storage amount of the braided stent are improved, and the drug coating in the delivery of the braided stent is prevented from falling off accidentally. The utility model further provides a braided stent system comprising the braided stent, the system further comprises a push guide wire and a delivery tube sheath used for accommodating the braided stent and the push guide wire, and the braided stent is loaded at the distal end of the push guide wire.

The structure of the braided stent and the braided stent system of the present invention will be described in detail with reference to the accompanying drawings and various embodiments.

Fig. 1-6 are schematic structural views of a braided stent system and a braided stent according to a first embodiment of the present invention. As shown in fig. 1, in a first embodiment of the present invention, a braided stent system includes a delivery sheath 11, a push guidewire 12, and a braided stent 14. The braided stent 14 is loaded on the distal end of the push guidewire 12, and the delivery sheath 11 is used for accommodating the push guidewire 12 and the braided stent 14. Further, in this embodiment, the braided stent system may further include a visualization ring 13 disposed on the pushing wire 12 for indicating complete release of the braided stent 14 and a visualization spring 15 for indicating a tip end of the pushing wire 12. As shown in fig. 2, in this embodiment, the braided stent 14 is formed by cross-braiding at least one braided wire 141. Specifically, when a plurality of braided wires 141 are used, the plurality of braided wires 141 may be braided with each other in a crossing manner, in a parallel manner, or in a nested manner, or may be axially connected end to end. The braided wire 141 may be a metal alloy wire or other high-temperature material wire, for example, a nickel alloy braided wire, a cobalt-based alloy braided wire, or the like.

As shown in fig. 2, in order to improve the drug storage capacity and drug storage capacity of the braided stent 14, at least a part of the surface of the braided wire 141 is provided with one or more grooves 142, and at least a part of the grooves 142 are coated with a drug coating. Here, at least a part of the surface of the braided wire 141 is provided with the groove 142, which means that: when a plurality of braided wires 141 are provided, a groove 142 may be provided on the surface of one or more braided wires 141; as for the braided wire 141 provided with the grooves 142, the grooves 142 may be provided only partially on the surface thereof, for example, the grooves 142 are provided at intervals in the extending direction thereof, the grooves 142 are provided only in the middle portion, or the grooves 142 are provided only in the end portions, and the like. The coating of the drug coating in at least a portion of the grooves 142 means that the drug coating can be coated in all the grooves 142, or the drug coating can be coated in a portion of the grooves 142, and the drug coating is not coated in a portion of the grooves 142.

Therefore, the grooves 142 for containing the medicine are formed in at least part of the surface of the braided stent 14, and the medicine coating is coated in at least part of the grooves 142, so that the medicine storage capacity and the medicine storage amount of the braided stent 14 are improved, and the accidental falling of the medicine coating in the delivery of the braided stent 14 is avoided, so that the problems of low medicine content and uneven coating caused by thin wire diameter and high mesh density of the existing intravascular braided stent 14 for treating intracranial aneurysm are solved, and the problems of high clinical risk caused by the fact that the medicine on the existing braided stent is easy to adhere or even agglomerate between stent meshes, and further the coating falls off in the delivery and expansion process to cause intracranial far-end vascular embolism and the like are solved. In addition, compared with a laser cutting bracket with a medicine carrying groove, the utility model solves the problems that the rod diameter of the laser cutting bracket is larger, the adherence is poor, so that thrombus in the bracket is easy to generate, and the laser cutting bracket can not be used for treating intracranial aneurysm.

In this embodiment, the drug may be at least one of an anticoagulant drug, an anticancer drug, a vascular smooth muscle cell proliferation inhibition drug, an anti-inflammatory drug, or an immunosuppressive drug, as required, and the present invention is not limited thereto, and the drug may also be other types of drugs as required.

In this embodiment, as shown in fig. 2, the groove 142 extends along the extending direction of the knitting yarn 141 to form a continuous groove 142 on the knitting yarn 141, which can increase the space for filling the groove 142 with the medicine. The grooves 142 are preferably open on the outer surface of the braided stent 14. However, the present invention is not limited thereto, and in other alternative embodiments, the inner surface of the woven stent 14 may be provided with the grooves 142, or both the inner surface and the outer surface of the woven stent 14 may be provided with the grooves 142.

In another alternative embodiment, the grooves may be pits distributed on the surface of the braided wire 141. A plurality of the pits are distributed at intervals on the surface of the braided wire 141. Alternatively, the pits are uniformly arranged in the extending direction of the braided wire 141. When the pits are small, more than one row of pits may be provided on the braided wire 141. The pits may be, for example, spherical pits, or pits of other shapes.

In this embodiment, as shown in fig. 3 to 5, the shape of the groove may be a sector, an ellipse, or a polygon in the cross section of the braided wire 141. For the sake of distinction, in fig. 3-5, the grooves are respectively denoted by

reference numerals

142a, 142b and 142 c. E.g. grooves 142a shown in fig. 3The cross-section is a sector, the cross-section of the groove 142b shown in fig. 4 is a trapezoid, and the cross-section of the groove 142c shown in fig. 5 is a triangle, and the present invention is not limited to the shape shown in the drawings. The braided wire 141 has a radial dimension of 15 to 150 μm, preferably 15 to 60 μm. In this embodiment, the braided wire 141 may be a round wire as shown in fig. 3 to 5, and the diameter of the braided wire 141 is 15 to 150 μm, preferably 15 to 60 μm. In this embodiment, in the cross section of the braided wire 141, the area of the groove is 3% to 40%, preferably 4% to 20%, of the cross section of the braided wire 141 without the groove. Here, the cross-sectional area of the braided wire 141 without the groove refers to: for the braided wire 141 using a round wire material, taking the right side in fig. 6 as an example, the cross-sectional area a1 when the groove 142a is not provided in the braided wire 141 is

d is the diameter of the round wire. The area a2 of the groove refers to the cross-sectional area lost by the braided wire 141 after the groove 142a is provided, i.e., the portion of the hatched area a2 shown on the left side in fig. 6. When the braided wire 141 having another cross-sectional shape is used, the radial dimension refers to a distance between two farthest points on the cross-section of the braided wire 141. For example, in other alternative embodiments, the braided wire may be a square wire, the width of the braided wire is 15 to 150 μm, preferably 15 to 60 μm, and/or the thickness of the braided wire is 15 to 150 μm, preferably 15 to 60 μm. In an embodiment where a square wire is used as the braided wire, the cross-sectional area of the braided wire when the groove is not provided is equal to the width multiplied by the thickness of the braided wire.

Fig. 7 is a schematic structural view of a braided wire 141 according to a second embodiment of the present invention. This second embodiment is the same as the first embodiment in that the braided stent system includes a delivery sheath 11, a push guidewire 12, and a braided stent 14, and the braided stent 14 is formed by cross-braiding at least one braided wire 141. The second embodiment differs from the first embodiment in that: in the second embodiment, the braided wire 141 is formed by winding a first braided wire 141a and a second braided wire 141b, and at least a part of the surface of the second braided wire 141b is provided with the groove 142. The first weaving wire 141a may be one or more, the second weaving wire 141b may be one or more, and fig. 7 illustrates an example of using one first weaving wire 141a and one second weaving wire 141 b. In this second embodiment, the braided wire refers to a wire material that is cross-braided to obtain a braided stent, and the braided wire refers to a wire material that is combined to obtain a braided wire. Namely, the braided wires are combined to obtain braided wires, and then the braided wires are crossed and braided to obtain the braided stent.

Specifically, as shown in fig. 7, the first braided wire 141a serves as a mandrel, the second braided wire 141b is spirally wound on the outer side of the first braided wire 141a to form a spiral spring structure surrounding the first braided wire 141a, and the groove 142 is disposed on the surface of the second braided wire 141 b. By adopting the structure of the knitting yarn 141 of the embodiment, under the condition that the length of the knitted stent 14 is fixed, because the length of the second knitting yarn 141b is greater than the length of the knitting yarn 141 obtained by combining the first knitting yarn 141a and the second knitting yarn 141b, the length of the groove 142 can be greatly increased, and the space of the groove 142 for accommodating the medicine is also increased, so that the medicine storage capacity of the knitted stent can be further improved, and the problems of thrombus, intimal hyperplasia and the like after the stent is implanted can be effectively treated.

In this embodiment, when the braided stent is braided with a plurality of braided wires 141, each braided wire 141 may have the structure shown in fig. 7, or a part of the braided wires 141 may have the structure shown in fig. 7, and a part of the braided wires 141 may have the structure in the first embodiment.

In this embodiment, the first braided wire 141a may be made of a common medical metal material, such as a nickel alloy, a cobalt-based alloy, or the like. The second braided wire 141b may be made of a developable metal material, such as gold, platinum-tungsten, platinum-iridium, platinum alloy, and the like. Therefore, the developing function of the woven support can be further enhanced, an operator can be helped to judge the opening state, the wall adhering state and the specific position of the woven support, and the operation is convenient to carry out. In other alternative embodiments, it is within the scope of the present invention to adopt a developable metal material for both the first weaving wire 141a and the second weaving wire 141b, adopt a developable metal material for the first weaving wire 141a and adopt a common medical metal material for the second weaving wire 141b, or adopt a common medical metal material or other high temperature materials for both the first weaving wire 141a and the second weaving wire 141 b. In addition, at least a portion of the braided wire 141 in the first embodiment shown in fig. 2 may be made of a developing metal material such as gold, platinum-tungsten, platinum-iridium, and platinum alloy, to enhance the developing function of the braided stent itself.

In this embodiment, the groove 142 extends along the extending direction of the second braided wire 141b to form a groove 142 continuous with the second braided wire 141b, and the groove 142 is formed on the outer side surface of the coil spring structure, so that the space for filling the groove 142 with the medicine can be increased. In another alternative embodiment, the groove 142 may also be formed on the inner side surface of the coil spring structure, or both the inner side surface and the outer side surface of the coil spring structure are opened with the groove 142. In another alternative embodiment, the groove 142 is a gap in a surface of the coil spring structure, such as a gap between two adjacent coils. In yet another alternative embodiment, the grooves 142 may also be pits distributed on the surface of the second braided wire 141 b. A plurality of the concave pits are distributed at intervals on the surface of the second braided wire 141 b. Alternatively, the dimples are uniformly arranged along the extending direction of the second weaving wire 141 b. When the dimples are small, more than one row of dimples may be provided on the second weaving wire 141 b. The pits may be, for example, spherical pits, or pits of other shapes.

In this embodiment, the shape of the groove 142 may be a sector, an ellipse, a triangle, a trapezoid, or other polygons in the cross section of the second weaving wire 141 b. In the cross section of the second weaving wire 141b, the area of the groove 142 is 3% to 40%, preferably 4% to 20% of the cross section of the second weaving wire 141b without the groove 142. The first and

second weaving wires

141a and 141b may have a radial dimension of 15 to 150 μm, preferably 15 to 60 μm, respectively. The radial dimensions of the first and

second braided wires

141a, 141b may be the same, or the radial dimension of the first braided wire 141a may be greater than the radial dimension of the second braided wire 141b to better support the coil spring structure.

In this embodiment, the first and

second weaving wires

141a and 141b are combined in such a manner that the first weaving wire 141a is used as a mandrel and the second weaving wire 141b is spirally wound on the outside of the first weaving wire 141 a. In other alternative embodiments, the first knitting wire 141a and the second knitting wire 141b may be wound in other manners, for example, two knitting wires are wound in a crossing manner or in parallel to form a complete knitting wire 141, and the length of the groove 142 on the knitting wire 141 may also be increased. In this embodiment, an example of combining two kinds of knitting yarns to obtain a knitting yarn is given, in other alternative embodiments, a knitting yarn may also be obtained by combining more kinds of knitting yarns, the knitting yarns may be arranged in a side-by-side manner, intertwined with each other, or connected end to obtain a knitting yarn, and one or more of the knitting yarns are provided with a groove.

The preparation method of the braided stent comprises the following steps:

s100: providing at least one braided wire, wherein one or more grooves are formed on the surface of the braided wire and are used for containing medicines;

s200: the at least one knitting line is crossed and knitted to obtain a knitted support body;

s300: immersing the braided stent body in a medicament, or spraying a medicament in a groove of the braided stent body to form a medicament coating in the groove, thereby obtaining the braided stent. I.e., by dip coating or spray coating, in the grooves of the braided stent.

Grooves for containing medicines are formed on the surface of the braided stent obtained by the method, and medicine coatings are arranged in at least part of the grooves, so that the medicine storage quantity and the medicine storage capacity of the braided stent are improved, and the accidental falling of the medicine coatings in the conveying of the braided stent are avoided.

In one embodiment, in the preparation of the braided stent of the first embodiment, in the step S100, when at least one braided wire is provided, the groove of the braided wire may be obtained by a drawing process or a femtosecond laser cutting process to obtain the braided wire with one or more grooves formed on the surface. Specifically, when the drawing process is adopted, the step S100: providing at least one braided wire, comprising the steps of:

enabling the braided wire raw material to enter a drawing die hole through the first end of the drawing die hole, wherein at least one bulge is arranged on the inner surface of the drawing die hole; the braided wire raw material can be a metal blank or other high-temperature materials, for example, the braided wire can be made of common medical metal materials such as nickel alloy, cobalt-based alloy and the like, and can also be made of developing metal materials such as gold, platinum tungsten, platinum iridium, platinum alloy and the like;

obtaining the braided wire from the second end of the drawing die hole, wherein a groove corresponding to the position of the protrusion is formed on the surface of the braided wire; for example, when one protrusion or a plurality of protrusions distributed along the axial direction are arranged in the drawing die hole, one or a plurality of continuous strip-shaped grooves extending along the extending direction of the braided wire are formed on the surface of the braided wire, and when a plurality of protrusions not distributed along the axial direction are arranged in the drawing die hole, a plurality of concave-shaped grooves are formed on the surface of the braided wire.

In another embodiment, when the grooves of the braided wire are obtained by a femtosecond laser cutting method, the step S100: providing at least one braided wire, comprising the steps of:

the method comprises the following steps of (1) enabling a braided wire raw material to enter a drawing die hole through a first end of the drawing die hole, wherein the braided wire raw material can be a metal blank (developed or not) or other high-temperature materials, and in the other embodiment, the inner surface of the drawing die hole is smooth and is not provided with bulges;

obtaining a braided wire without a groove from the second end of the drawing die hole;

at least one groove is formed on the surface of the braided wire by adopting a femtosecond laser cutting method, for example, one or more continuous strip-shaped grooves extending along the extension direction of the braided wire can be formed, and a plurality of concave pit-shaped grooves distributed on the surface of the braided wire can also be formed.

The woven stent according to the second embodiment of the present invention can also be prepared by the above steps S100 to S300. The method of manufacturing the braided stent of the second embodiment differs from the method of manufacturing the braided stent of the first embodiment in that: the manner of providing the braided wire in step S100 of the second embodiment is different.

In one embodiment, in preparing the braided stent of the second embodiment described above, the step S100: providing at least one braided wire, comprising the steps of:

providing a first weaving wire and a second weaving wire, spirally winding the second weaving wire on the outer side of the first weaving wire to form a spiral spring structure surrounding the first weaving wire, wherein the surface of the spiral spring structure is provided with a gap so as to form one or more grooves on the surface of the weaving wire, and the spiral spring structure forms the weaving wire with one or more grooves on the surface. I.e. the gaps of the helical spring structure act as grooves for accommodating the medicament.

In another embodiment, in preparing the braided stent of the second embodiment, the step S100: providing at least one braided wire, comprising the steps of:

providing a first weaving wire and a second weaving wire, spirally winding the second weaving wire on the outer side of the first weaving wire to form a spiral spring structure surrounding the first weaving wire, wherein the grooves are formed on the surfaces of the first weaving wire and/or the second weaving wire, and the spiral spring structure forms the weaving wire with one or more grooves formed on the surface.

For example, when the grooves are formed on the surface of the second weaving wire, the first weaving wire may be obtained by using a drawing die hole with a smooth inner surface, the material of the first weaving wire may be a common medical metal material, a developable metal material or other high-temperature materials, the second weaving wire may be obtained by using a drawing die hole with a protrusion on the inner surface, or the second weaving wire may be obtained by using a drawing die hole with a smooth inner surface and then forming the grooves by femtosecond laser cutting, and the material of the second weaving wire may be a common medical metal material, a developable metal material or other high-temperature materials.

In the above embodiments, the drug may be at least one of an anticoagulant drug, an anticancer drug, a vascular smooth muscle cell proliferation inhibition drug, an anti-inflammatory drug, or an immunosuppressive drug, as required, and the present invention is not limited thereto, and the drug may also be other types of drugs as required. The groove of the same braided stent can be provided with a coating of one drug, and also can be provided with coatings of various different drugs. For example, when one drug coating is disposed in one of the grooves and another drug coating is disposed in another of the grooves, the grooves at different positions are respectively immersed in different drugs or the grooves at different positions are respectively sprayed with different drugs when the drug coatings are formed in step S300. In another embodiment, after a drug coating is disposed in at least a portion of the recess, another drug coating may be further applied to the surface of the formed drug coating. For example, when the drug coating is formed in step S300, at least a portion of the grooves is first immersed in one drug, and then the grooves are taken out and then immersed in another drug, or at least a portion of the grooves is first sprayed with one drug and then the grooves are sprayed with another drug.

(1) the utility model provides a braided stent formed by cross-braiding braided wires and a braided stent system comprising the braided stent, wherein grooves are formed in original braided wires adopted by the braided stent through a drawing process or femtosecond laser cutting treatment, the grooves are used for containing medicines, and medicine coatings are arranged in at least part of the grooves, so that the medicine storage amount of the braided stent can be increased.

(3) Furthermore, because the medicine coating is accommodated in the groove of the knitting wire, the medicine coating can not be adhered or caked at the cross part between meshes or knitting wire due to the small meshes of the knitting stent, and further the problems of blood vessel embolism and the like caused by falling off in the conveying process due to the adhesion or caked of the medicine coating can be avoided. Meanwhile, most of the medicine is not on the surface of the braided stent, so that the medicine coating cannot fall off even if slippage between braided wires occurs in the process of releasing the medicine along with the delivery of the braided stent or friction occurs between the outer surface of the braided stent and the inner surface of a delivery sheath, and the effectiveness of an integral product formed by the braided stent and the medicine is improved.

The foregoing is a more detailed description of the utility model in connection with specific preferred embodiments and it is not intended that the utility model be limited to these specific details. For those skilled in the art to which the utility model pertains, several simple deductions or substitutions can be made without departing from the spirit of the utility model, and all shall be considered as belonging to the protection scope of the utility model.

Claims

1. A woven stent is formed by cross weaving at least one woven wire, one or more grooves are formed in the surface of at least part of the woven wire, and a medicine coating is coated in at least part of the grooves.

2. The woven stent of claim 1 wherein the grooves extend in the direction of the extent of the woven wire or the grooves are dimples distributed across the surface of the woven wire.

3. The braided stent of claim 1 wherein the shape of the groove is a sector, an ellipse, or a polygon in the cross-section of the braided wire.

4. The braided stent of claim 1 wherein the braided wires have a radial dimension of 15 to 150 μm.

5. The braided stent of claim 4 wherein the braided wires have a radial dimension of 15 to 60 μm.

6. The braided stent of claim 1 wherein the area of the groove in the cross-section of the braided wire is between 3% and 40% of the cross-sectional area of the braided wire when the groove is not provided.

7. The braided stent of claim 1 wherein said braided wire is formed by a first braided wire and a second braided wire wound helically around the outside of said first braided wire to form a helical spring structure encircling said first braided wire.

8. The braided stent of claim 7 wherein the gaps of the helical spring structure are the grooves or the surface of the first braided wire and/or the second braided wire is provided with the grooves.

9. The woven stent of claim 8 wherein the second woven wire is a developable wire.

10. A braided stent system comprising a delivery sheath carried on a distal end of a push guidewire, and the braided stent of any one of claims 1-9, the delivery sheath being adapted to receive the push guidewire and the braided stent.