阅读说明：本技术 医用自膨胀支架及其制造方法 (Medical self-expanding stent and manufacturing method thereof ) 是由 魏征 穆云泓 孙云昌 于 2021-01-07 设计创作，主要内容包括：本发明公开了一种医用自膨胀支架及其制造方法,医用自膨胀支架包括：多个单体支架、多个柔性连接件和药物涂层,每个单体支架为环形,且被构造成可在径向发生弹性形变,多个单体支架同轴设置且沿轴向间隔开分布。每个柔性连接件用于将多个单体支架连接成串,各个柔性连接件沿单体支架的周向对称分布或均匀分布,每个柔性连接件同时连接所有单体支架,柔性连接件连接在多个单体支架的内侧和/或外侧,多个柔性连接件和多个单体支架配合构成医用自膨胀支架本体。而药物涂层设置在医用自膨胀支架本体的外表面上。由此,增加了医用自膨胀支架的顺应性,可以适应复杂的病变情况。(The invention discloses a medical self-expanding stent and a manufacturing method thereof, and the medical self-expanding stent comprises: the single stent comprises a plurality of single stents, a plurality of flexible connecting pieces and a drug coating, wherein each single stent is annular and is constructed to be elastically deformed in the radial direction, and the plurality of single stents are coaxially arranged and are distributed at intervals in the axial direction. Every flexible connectors is used for connecting a plurality of monomer supports into a string, and each flexible connector is along monomer support's circumference symmetric distribution or evenly distributed, and all monomer supports are connected simultaneously to every flexible connectors, and flexible connectors connects the inboard and/or the outside at a plurality of monomer supports, and a plurality of flexible connectors and a plurality of monomer support cooperation constitute medical self-expanding support body. And the drug coating is arranged on the outer surface of the medical self-expanding stent body. Therefore, the compliance of the medical self-expanding stent is increased, and the medical self-expanding stent can adapt to complex pathological conditions.)

1. A medical self-expanding stent, comprising:

the single supports are annular, each single support is configured to be elastically deformed in the radial direction, and the single supports are coaxially arranged and axially distributed at intervals;

the flexible connecting pieces are used for connecting the single supports into a string, the flexible connecting pieces are symmetrically or uniformly distributed along the circumferential direction of the single supports, each flexible connecting piece is simultaneously connected with all the single supports, the flexible connecting pieces are connected to the inner sides and/or the outer sides of the single supports, and the flexible connecting pieces and the single supports are matched to form a medical self-expansion support body; and

and the drug coating is arranged on the outer surface of the medical self-expansion stent body.

2. The medical self-expanding stent according to claim 1, wherein each of the single stents comprises a plurality of rings and a plurality of connecting rods connecting adjacent rings, and the plurality of rings are coaxially arranged and axially spaced apart.

3. The medical self-expanding stent of claim 2,

each monomer support comprises 2-5 ring bodies; and/or

The width of the ring body is 0.03mm-0.2 mm; and/or

The thickness of the ring body is 0.05mm-0.2 mm; and/or

The ring body extends along the wave shape to form a wave-shaped ring, and the wave-shaped ring is provided with wave crests and wave troughs, and the angle of each wave crest and each wave trough is 105-145 degrees.

4. The medical self-expanding stent according to claim 2 or 3, wherein the width of the connecting rod is 0.02mm to 0.19mm, and the ratio of the width of the ring body to the width of the connecting rod is 1.2 to 1.5.

5. The medical self-expanding stent according to any one of claims 1-3, wherein said flexible connecting member is a porous structure.

6. The medical self-expanding stent according to claim 2 or 3, wherein the flexible connecting member is a strip-shaped structure and has a length direction parallel to the axial direction of the single stent, and the flexible connecting member coincides with the connecting rod.

7. The medical self-expanding stent according to claim 6, wherein the flexible connectors comprise outer connecting films and inner films, the outer connecting films correspond to the inner films in a one-to-one manner, the inner films are located on the inner sides of the single stents and are attached to the inner side walls of the ring bodies and the inner surfaces of the connecting rods, the outer connecting films are located on the outer sides of the single stents and are attached to the outer side walls of the ring bodies and the outer surfaces of the connecting rods, and the side surfaces of the connecting rods are bonded to the inner films after being coated by the two sides of the outer connecting films.

8. A method for manufacturing a medical self-expandable stent, wherein the medical self-expandable stent is the medical self-expandable stent according to any one of claims 1 to 7, the method comprising:

s1, preparing a plurality of single stents by cutting or weaving;

s2, sequentially sleeving the single supports on an inner mold pipe, and inserting positioning columns on the inner mold pipe for positioning, so that the single supports are coaxially arranged and the axial distance is a preset distance;

s3, connecting the single stents into a string by a plurality of flexible connectors to obtain a medical self-expanding stent body;

s4, detaching the positioning column, and taking down the medical self-expansion support body;

s5, atomizing the medicine liquid containing the medicine into particles, and coating the particles on the outer surface of the medical self-expansion stent body to obtain the medical self-expansion stent.

9. The method of manufacturing of claim 8, wherein the flexible connection comprises an outer connection membrane and an inner membrane,

before the step S2, a step S11 is performed:

a second air hole is formed in the inner mold pipe, an adhesive is coated on one surface of the inner mold, and the other surface of the inner mold is adsorbed on the inner mold pipe by negative pressure along the circumferential direction of the inner mold pipe through the second air hole;

further, the step S3 includes:

follow the circumference of interior mould pipe sets up a plurality of outer matrixes of seting up first gas pocket, outer connection membrane with outer matrix one-to-one, one of them surface coating of outer connection membrane has the adhesive, and another surface quilt outer matrix passes through first gas pocket negative pressure adsorbs, removes outer matrix makes outer connection membrane's both sides with the both sides of inner membrane are laminated and are bonded each other.

10. The manufacturing method according to claim 9,

after the step S3 is performed, before the step S4 is performed, the step S31 is further performed: raising the temperature of the inner mould pipe and the outer mould sheet to 400-450 ℃, and after the temperature is reached, respectively blowing inert gases with the same temperature as the inner mould pipe and the outer mould sheet through the second air hole of the inner mould pipe and the first air hole of the outer mould sheet, and keeping the temperature for 10-30 min; and

step S32 is performed: stopping heating the inner die tube and the outer die piece, and blowing cooling air to cool the second air hole of the inner die tube and the first air hole of the outer die piece;

when the step S4 is performed, the method further includes: the outer mold piece is removed.

Technical Field

The invention relates to the field of medical instruments, in particular to a medical self-expansion stent and a manufacturing method thereof.

Background

The stent is a medical instrument commonly used in interventional operations, is widely applied to body lumens such as blood vessels, urethra, airway, esophagus, nasal cavity and the like, and can effectively solve the problems of body lumen stenosis, infarction and the like, thereby effectively improving the survival probability and the survival quality of patients.

Common stents include balloon expandable stents as well as self-expanding stents. The saccule expansion bracket is a bracket which is pre-arranged on a saccule, is conveyed to a lesion part together with the saccule, pressurizes the saccule to expand the saccule, so that the bracket is expanded, and the expanded bracket supports the lesion part to ensure that the lesion part is smooth. The self-expanding stent is a stent which is contained in the conveying catheter after being radially compressed, is conveyed to a lesion part through the conveying catheter and then is pushed out, and after the limitation is removed, the stent self-expands to support the lesion part, so that the lesion part is smooth.

However, the only physical support cannot repair or treat the lesion, and the stent may stimulate the body to cause inflammation after implantation, resulting in intimal hyperplasia or scar tissue, thereby causing restenosis of the body lumen. Based on the above, the existing balloon expandable stent and self-expandable stent can be loaded with drugs to treat the stenosis of the body lumen and prevent or reduce the occurrence of the restenosis of the body lumen.

In order to enable the drug to better repair or treat the diseased site, the stent needs to adapt to all movements and deformations of the lumen to better conform to the inner wall of the lumen, so that the drug can be effectively released to the diseased site.

However, the movement and deformation of the lumen is diverse. For example, the coronary arteries undergo slight expansion and contraction as the heart beats. In contrast, peripheral arteries have more complex motions and deformations, and in addition to expansion and contraction, also twist. In addition, the carotid artery also experiences similar motion and deformation as the peripheral artery due to the motion of the head.

However, the balloon expandable stent has strong radial stiffness and torsional stiffness, not only can not be well attached to the inner wall of the lumen, but also can limit the expansion, contraction or torsion of the lumen, so that the inner wall of the lumen can be scraped and abraded, and the lumen is damaged. Although the existing self-expanding stent has good elasticity in the radial direction and can conform to the expansion or compression of the lumen, the existing self-expanding stent still has certain torsional rigidity and cannot well adapt to the torsion of the lumen.

In addition, both the existing balloon expandable stent and the self-expandable stent are integrated, and all parts are mutually constrained, cannot be independently expanded, contracted or twisted, and cannot be flexibly adjusted.

In conclusion, the existing balloon expandable stent and self-expandable stent have poor compliance and cannot adapt to complex pathological changes, so that the medicine cannot better repair or treat pathological changes.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, an object of the present invention is to provide a self-expandable stent with good compliance, in which each part of the stent can expand, contract or twist relatively independently, and can better fit the affected part, so that the drug can effectively repair or treat the affected part.

A medical self-expanding stent according to an embodiment of the first aspect of the invention comprises: a plurality of monolithic stents, a plurality of flexible connectors, and a drug coating. Each monomer support is annular, and each monomer support is constructed and can radially take place elastic deformation, a plurality of the monomer support coaxial arrangement and along axial interval distribution. Every flexible connectors is used for being a plurality of monomer support connects into the cluster, each flexible connectors follows monomer support's circumference symmetric distribution or evenly distributed, every flexible connectors connects all simultaneously monomer support, flexible connectors connects a plurality of monomer support's inboard and/or outside, it is a plurality of flexible connectors and a plurality of monomer support cooperation constitutes medical self-expanding support body. And the drug coating is arranged on the outer surface of the medical self-expanding stent body.

Therefore, the flexible connecting parts are distributed on any side or two sides of the single bracket, and the connection diversity of the flexible connecting parts is increased. In addition, the flexible connecting piece has flexibility, so that on one hand, the interference effect among the monomer stents connected by the flexible connecting piece is small, and the monomer stents can be expanded, contracted or twisted relatively independently; on the other hand, the medical self-expanding stent body can be axially extended, contracted, twisted or bent to a certain degree, so that the medical self-expanding stent body can adapt to the complex pathological changes and is fully attached to the pathological changes, and the medicine in the medicine coating can effectively repair or treat the pathological changes.

In some embodiments, each of the single-body brackets includes a plurality of ring bodies and a plurality of connecting rods connecting adjacent ring bodies, and the ring bodies are coaxially arranged and axially spaced apart.

In some embodiments, each of the unitary scaffolds includes 2-5 of the loops.

Optionally, the ring body has a width of 0.03mm to 0.2 mm.

Optionally, the ring body has a thickness of 0.05mm to 0.2 mm.

Optionally, the ring body extends along a wave shape to form a wave-shaped ring, and the wave-shaped ring is provided with wave crests and wave troughs, and the angle of each wave crest and each wave trough is 105-145 degrees.

In some embodiments, the connecting rod has a width of 0.02mm to 0.19mm, and the ratio of the width of the ring body to the width of the connecting rod is 1.2 to 1.5.

In some embodiments, the flexible connector is a porous structure.

In some embodiments, the flexible connecting member is a strip-shaped structure and the length direction is parallel to the axial direction of the single bracket, and the flexible connecting member is coincident with the connecting rod.

In some embodiments, the flexible connecting element includes an outer connecting film and an inner film, the outer connecting film corresponds to the inner film one by one, the inner film is located inside the single support and attached to the inner side wall of the ring body and the inner surface of the connecting rod, the outer connecting film is located outside the single support and attached to the outer side wall of the ring body and the outer surface of the connecting rod, and the two sides of the outer connecting film coat the connecting rod and then are bonded to the inner film.

According to a second aspect of the present invention, there is provided a method of manufacturing a medical self-expanding stent, the medical self-expanding stent being the medical self-expanding stent according to any one of the above embodiments, the method including:

s1, preparing a plurality of single stents by cutting or weaving;

s2, sequentially sleeving the single supports on an inner mold pipe, and inserting positioning columns on the inner mold pipe for positioning, so that the single supports are coaxially arranged and the axial distance is a preset distance;

s3, connecting a plurality of single stents into a string by a plurality of flexible connectors to obtain a medical self-expanding stent body;

s4, detaching the positioning column, and taking down the medical self-expansion support body;

s5, atomizing the medicine liquid containing the medicine into particles, and coating the particles on the outer surface of the medical self-expansion stent body to obtain the medical self-expansion stent.

In some embodiments, the flexible connector comprises an outer connecting membrane and an inner membrane, and before performing the step S2, the step S11 is performed:

a second air hole is formed in the inner mold pipe, an adhesive is coated on one surface of the inner mold, and the other surface of the inner mold is adsorbed on the inner mold pipe by negative pressure along the circumferential direction of the inner mold pipe through the second air hole;

further, the step S3 includes:

follow the circumference of interior mould pipe sets up a plurality of outer matrixes of seting up first gas pocket, outer connection membrane with outer matrix one-to-one, one of them surface coating of outer connection membrane has the adhesive, and another surface quilt outer matrix passes through first gas pocket negative pressure adsorbs, removes outer matrix makes outer connection membrane's both sides with the both sides of inner membrane are laminated and are bonded each other.

In some embodiments, after the step S3 is performed, before the step S4 is performed, a step S31 is further performed: raising the temperature of the inner mould pipe and the outer mould sheet to 400-450 ℃, and after the temperature is reached, respectively blowing inert gases with the same temperature as the inner mould pipe and the outer mould sheet through the second air hole of the inner mould pipe and the first air hole of the outer mould sheet, and keeping the temperature for 10-30 min; and

step S32 is performed: and stopping heating the inner die tube and the outer die piece, and blowing cooling air to cool the second air hole of the inner die tube and the first air hole of the outer die piece.

When the step S4 is performed, the method further includes: the outer mold piece is removed.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic view of a medical self-expanding stent according to an embodiment of the present invention.

Fig. 2 is an enlarged schematic view of a portion M in fig. 1.

Fig. 3 is a schematic view of a one-piece stent of the medical self-expandable stent according to an embodiment of the present invention.

Fig. 4 is a schematic view showing the attachment of an outer connecting membrane to an inner membrane of a medical self-expandable stent according to an embodiment of the present invention.

Fig. 5 is a schematic view of a manufacturing mold for a medical self-expanding stent according to an embodiment of the present invention.

Fig. 6 is a schematic view of an outer mold sheet for manufacturing a medical self-expanding stent according to an embodiment of the present invention.

FIG. 7 is a schematic illustration of an inner membrane tube for making a medical self-expanding stent, according to an embodiment of the present invention.

Fig. 8 is a method of manufacturing a medical self-expanding stent according to an embodiment of the present invention.

Reference numerals:

a medical self-expanding stent 100;

a single body frame 10; a ring body 11; an inner side wall 111; an outer side wall 112; a peak 113; wave troughs 114; a connecting rod 12;

a flexible connector 20; an outer connecting film 21; an inner membrane 22;

an inner mold tube 40; a second air hole 41;

an outer die 50; a relief hole 51; a first air vent 52;

and a positioning post 60.

Detailed Description

The embodiments of the present invention will be described in detail below, and the embodiments described with reference to the drawings are exemplary and should not be construed as specifically limiting the present invention.

A medical self-expanding stent 100 and a method of manufacturing the same according to an embodiment of the present invention will be described with reference to fig. 1 to 8.

As shown in fig. 1 and 2, the medical self-expanding stent 100 includes: a plurality of single stents 10, a plurality of flexible connectors 20, and a drug coating. In the present embodiment, a plurality of means includes two or more.

Each of the unit supports 10 is annular, each of the unit supports 10 is configured to be elastically deformable in a radial direction, and a plurality of the unit supports 10 are coaxially arranged and axially spaced apart.

Thus, after being implanted into a body lumen (e.g., blood vessel), the annular single stent 10 can be used to open the lesion without affecting the normal flow of fluid (e.g., blood) in the body lumen. Every monomer support 10 can radially take place elastic deformation, has increased the variability of monomer support 10 shape, has improved medical self-expanding support 100's practicality for in addition, make monomer support 10 have self-expanding performance, thereby make medical self-expanding support 100 can adapt to the expansion of organism lumen, compression. In addition, when three or more of the single stents 10 are provided, they may be uniformly spaced apart in the axial direction, or may be non-uniformly spaced apart in the axial direction. When the plurality of single stents 10 are uniformly distributed at intervals, the single stents can contact with the lesion part to the maximum extent for treatment; when the plurality of single stents 10 are unevenly distributed at intervals, the single stents 10 are selectively used to effectively treat a lesion while reducing the treatment cost, mainly aiming at the uneven distribution at intervals of the lesion.

Each flexible connecting piece 20 is used for connecting a plurality of monomer supports 10 into a string, each flexible connecting piece 20 is symmetrically distributed or uniformly distributed along the circumference of each monomer support 10, each flexible connecting piece 20 is connected with all monomer supports 10 at the same time, the flexible connecting pieces 20 are connected on the inner side and/or the outer side of each monomer support 10, and the plurality of monomer supports 10 and the plurality of flexible connecting pieces 20 are matched to form a medical self-expansion support body.

Specifically, the flexible connecting element 20 may connect a plurality of single-piece scaffolds 10 at the inner side of the single-piece scaffold 10, or may connect a plurality of single-piece scaffolds 10 at the outer side of the single-piece scaffold 10, or may be distributed at the inner and outer sides of the single-piece scaffold 10.

Therefore, the flexible connecting members 20 are distributed on either side or both sides of the single-body stent 10, and the diversity of connection of the flexible connecting members 20 is increased. In addition, because the flexible connecting element 20 has flexibility, on one hand, the interference effect between the single stents 10 connected by the flexible connecting element 20 is small, and the single stents can be expanded, contracted or twisted relatively independently, and on the other hand, the medical self-expanding stent body can be expanded, contracted, twisted or bent to a certain degree in the axial direction, so that the medical self-expanding stent body can adapt to complex pathological changes and can be fully attached to the pathological change part.

The drug coating is arranged on the outer surface of the medical self-expanding stent body.

The outer surface of the medical self-expanding stent body comprises the outer surface of the one-piece stent 10. In addition, when the flexible connectors 20 are connected to the outside of the plurality of single stents 10, the outer surface of the medical self-expanding stent body also includes the outer surface of the flexible connectors 20. The drug coating can be uniformly arranged on the outer surface of the medical self-expansion stent body, and can also be locally arranged on the outer surface of the medical self-expansion stent body according to actual requirements. As mentioned above, under the cooperation of the single stent 10 and the flexible connector 20, the medical self-expandable stent body can be flexibly adjusted to adapt to complex pathological changes, and the medical self-expandable stent body can be better attached to the inner wall of the lumen of the body, so that the drug in the drug coating can be effectively released to the pathological changes, and the medical self-expandable stent has better repairing or treating effects on the pathological changes. In addition, the medicine coating is only arranged on the outer surface of the medical self-expansion bracket body, so that the risk that the medicine is brought to other parts of the body by fluid in the body cavity and unnecessary side effects are generated on tissues and organs of other parts of the body is reduced.

Alternatively, the one-piece stent 10 may be made of a degradable material or a non-degradable material. Wherein, the degradable material is any one or the combination of at least two of the following materials: polylactide, polylactide-glycolide, polyglycolide, polyglycolic acid/polylactic acid copolymer, polyethylene glycol, polycaprolactone, polyorthoester, polyglycolic acid, polybutylene succinate, caprolactone-lactide copolymer, and polyhydroxyalkanoate. The non-degradable material is any one or a combination of at least two of the following materials: rubber, silicone rubber, polyester, polyvinyl chloride, polyurethane, stainless steel, nickel-titanium alloy, cobalt-chromium alloy.

Due to the different market segments, the single stent 10 made of degradable material has good degradability, so that the risk of secondary operation can be avoided, and the safety is improved. The single bracket 10 made of the non-degradable material has the advantages of relatively simple material, low manufacturing cost and low use cost.

From this, the monomer support 10 that different materials made can increase the selection variety of disease, combines self demand to select suitable oneself monomer support 10, improves monomer support 10's practicality, receives more people.

The number of the single stents 10 can be 2-200, and the specific number is determined according to the applied body lumen, the length of the lesion part and the like. For example, when the body lumen is a blood vessel, the number of the single stent 10 may be 2 to 15.

The outer diameter of the single stent 10 is 1mm to 10mm (corresponding to a blood vessel), which means the outer diameter that can be achieved by the single stent 10 without limitation in the radial direction, and the outer diameter of the single stent 10 may be larger or smaller depending on the body lumen to be used.

As shown in fig. 3, each of the single supports 10 includes a plurality of ring bodies 11 and a plurality of connecting rods 12 connecting adjacent ring bodies 11, and the plurality of ring bodies 11 are coaxially disposed and axially spaced apart.

The number of the ring bodies 11 forming the monomer support 10 is more than one, and may be 2 to 5, preferably 2 or 3. And, when the ring body 11 is 3-5, the ring body 11 is evenly distributed along the axial direction. When only one ring body 11 is used for forming the single bracket 10, the single bracket 10 is easy to incline and even fall down, and is difficult to fit with a lesion part; when the number of the ring bodies 11 forming the single stent 10 is five or more, the axial length of a single stent 10 is too long, so that the number of the single stents 10 that the medical self-expandable stent 100 can include is too small, and the flexible adjustment capability of the medical self-expandable stent 100 is drastically reduced. In addition, the ring bodies 11 are connected through the connecting rods 12, so that the structural strength of the single support 10 is improved, and the structural stability is higher.

The width of the ring body 11 is 0.03mm-0.2 mm. The motions of expansion, contraction and torsion of the body lumen act on the ring body 11, so the width of the ring body 11 cannot be too small, otherwise the strength of the ring body 11 is too small, and the ring body 11 cannot bear the expansion, contraction and torsion of the body lumen, and in addition, if the width of the ring body 11 is too small, the ring body 11 may generate linear cutting force on the inner wall of the body lumen, thereby damaging the body lumen; the width of the ring body 11 cannot be too large, which may cause the endothelialization of the medical self-expanding stent 100 to be too long.

The thickness of the ring body 11 is 0.05mm-0.2 mm. The elasticity of the ring body 11 is related to the thickness, within the range, the ring body 11 has better elasticity, and if the thickness is too large, the elasticity is smaller, so that the use requirement cannot be met; too small thickness makes it difficult to process on the one hand and too large elasticity on the other hand, which makes the medical self-expanding stent 100 unable to be compressed into a delivery catheter and thus difficult to deliver to a lesion site of a body lumen.

The ring body 11 extends in a wave shape to form a wave ring having peaks 113 and valleys 114. The wave ring has 4-20 wave crests 113 and wave troughs 114, respectively, the wave crests 113 and the wave troughs 114 are multiples of 3 or 2, and the angle of each wave crest 113 and wave trough 114 is 105-145 degrees.

Therefore, the angles of the wave crests 113 and the wave troughs 114 are controlled, and the single bracket 10 has small elasticity and cannot meet the use requirement if the angle is too small; if the angle is too large, the elasticity is too large, so that the medical self-expanding stent 100 cannot be compressed into a delivery catheter, and thus is difficult to deliver to a lesion site of a body lumen.

The wave crests 113 and wave troughs 114 of each ring body 11 are axially opposite, and the two ends of the connecting rod 12 are respectively connected to the mutually opposite wave crests 113 or mutually opposite wave troughs 114 of two adjacent ring bodies 11. In brief, a plurality of rings 11 are distributed in the axial direction of the unit bracket 10, the wave crests 113 of each ring 11 in the axial direction are all corresponding, and the wave troughs 114 of each ring 11 in the axial direction are also corresponding, that is, the projections of the plurality of rings 11 in the axial direction of the same unit bracket 10 coincide, or the wave crests 113 of one ring 11 and the wave crests 113 of the other ring 11 are in the same position in the circumferential direction, and the wave troughs 114 of one ring 11 and the wave troughs 114 of the other ring 11 are in the same position in the circumferential direction. The wave crests 113 and the wave troughs 114 of the ring body 11 are opposite in the axial direction, so that the single support 10 can be deformed in the radial direction conveniently, and the structural stability is maintained.

The number of the connecting rods 12 between two adjacent ring bodies 11 of each single bracket 10 is at least two, and the connecting rods 12 are symmetrically or uniformly distributed along the circumferential direction of the ring bodies 11. Specifically, when two connecting rods 12 are arranged between two adjacent rings 11, the connecting rods 12 are symmetrically distributed along the circumferential direction of the rings 11; when the number of the connecting rods 12 between two adjacent ring bodies 11 is more than two, the connecting rods 12 are distributed at equal intervals along the circumferential direction of the ring bodies 11.

The connecting rod 12 is a straight rod or a curved rod, and the width of the connecting rod 12 is 0.02mm-0.19 mm. The ratio of the width of the ring body 11 to the width of the connecting rod 12 is 1.2-1.5. The connecting rod 12 plays a connecting role and is used for connecting the ring body 11, and the expansion, contraction and torsion of the body cavity act on the ring body 11 instead of the connecting rod 12, so that the width of the connecting rod 12 can be designed to be smaller, and the width of the connecting rod 12 is slightly smaller than that of the ring body 11, so that the material consumption is reduced. For degradable monomeric scaffolds 10, the amount of material is reduced, which can reduce the burden of late degradation. Particularly, the material consumption is large, a large amount of lactic acid and acetic acid can be generated during degradation, the degradation products cannot be completely metabolized in a short time by body tissues, local aggregation can be caused, and then later sterile inflammation can be generated, and the amount of the material is reduced, namely the amount of the degradation products can be reduced, so that the later sterile inflammation can be avoided. In addition, the thickness of the connecting rod 12 corresponds to the thickness of the ring body 11.

Optionally, the flexible connector 20 is made of any one of the following materials: expanded polytetrafluoroethylene, polyethylene terephthalate, thermoplastic polyurethane elastomer rubber and silicon rubber. Therefore, the flexible connecting pieces 20 are made of the materials with good flexibility, the flexible connecting pieces 20 have good biocompatibility and compliance, the flexible connecting pieces are convenient to be attached to diseased regions, the harm of the flexible connecting pieces 20 to human bodies is reduced, the flexible connecting pieces 20 have small restraining effect on the single support frames 10, and the single support frames 10 have high independence in the processes of movement and deformation.

The flexible connecting piece 20 is of a porous structure, and is beneficial to the growth and the propagation of cells entering the porous structure and the realization of the rapid endothelialization of the medical self-expanding stent 100, so that the medical self-expanding stent 100 can be rapidly and stably arranged at a diseased region, and the medical self-expanding stent 100 is prevented from displacing under the action of fluid in a body lumen and the like to influence the repair or treatment of the diseased region.

The flexible connector 20 is a connection membrane. The number of the connecting films is at least two, and when the number of the connecting films is two, the connecting films are symmetrically distributed on the circumferential direction of the monomer support 10; when the number of the connection films exceeds two, the connection films are equally spaced in the circumferential direction of the cell holder 10.

From this, a plurality of monomer support 10 can be connected better to the connection membrane of symmetric distribution or equidistant distribution, make it form can stretch out and draw back in the axial, twist reverse or crooked medical self-expanding support 100 structure, and connect the membrane and be the platykurtic, when playing the connection effect, can not form linear cutting to the inner wall of organism lumen, can avoid causing the damage to the inner wall of organism lumen, also can not form linear cutting to monomer support 10, can avoid destroying the mechanical strength of monomer support 10.

The flexible connecting member 20 has a strip-shaped structure and a length direction parallel to the axial direction of the single bracket 10. When connected, the flexible connector 20 may be coincident with the connector rod 12 (as shown in FIG. 1), or may be offset from, and preferably coincident with, the connector rod 12.

Preferably, the flexible connecting element 20 is overlapped with the connecting rod 12, so that the radial limitation of the flexible connecting element 20 on the single-body support 10 can be reduced, and two adjacent single-body supports 10 can move in a relative staggered mode in the radial direction. In addition, the independence of the single-unit stents 10 can be increased, and the influence of one single-unit stent 10 on the adjacent single-unit stent 10 when the single-unit stent is compressed, expanded or twisted can be minimized.

The thickness of the flexible connecting piece 20 is 0.03mm-0.2 mm. The length of the flexible connector 20 depends on the overall desired length of the medical self-expanding stent 100. The width of the flexible connecting member 20 is greater than or equal to the width of the connecting rod 12 and less than the distance between the two rods constituting the peak 113. The distance between the two rods constituting the peak 113 refers to the distance between the ends of the two rods which are relatively separated. The width of the flexible connector 20 cannot be too small, otherwise it would be difficult to set; the width of the flexible connecting member 20 should not be too large, which would limit the individual supports 10 and affect the relative independence between the individual supports 10.

As shown in fig. 4, the flexible connector 20 includes an outer connecting membrane 21 and an inner membrane 22. It will be appreciated that the flexible connector 20 may include only the outer connecting membrane 21 (as shown in FIG. 1) or only the inner membrane 22. The outer connecting films 21 correspond to the inner films 22 one by one, the inner films 22 are located on the inner sides of the single body supports 10 and attached to the inner side walls 111 of the ring bodies 11 and the inner surfaces of the connecting rods 12, the outer connecting films 21 are located on the outer sides of the single body supports 10 and attached to the outer side walls 112 of the ring bodies 11 and the outer surfaces of the connecting rods 12, and the two sides of the outer connecting films 21 are bonded to the inner films 22 after wrapping the side surfaces of the connecting rods 12.

That is, the outer surface and the side surface of the tie bar 12 are covered with the outer connection film 21, and the inner surface of the tie bar 12 is bonded with the inner film 22, and the number of the inner films 22 is equal to the number of the outer connection films 21, corresponding to one another. After covering the side surfaces of the connecting rods 12, both sides of the outer connecting film 21 enter the inner side of the cell support 10 from the gap between two adjacent ring bodies 11, and are bonded to the inner film 22. Thus, when the flexible connecting element 20 is arranged, only two sides of the outer connecting membrane 21 and two sides of the inner membrane 22 need to be pressed and bonded, pressure does not need to be applied to the ring body 11 and the connecting rod 12, and damage to the single support 10 can be avoided.

Optionally, the materials of the outer connecting film 21 and the inner film 22 are the same.

The thickness of the inner membrane 22 is greater than the thickness of the outer connecting membrane 21. Therefore, the inner film 22 is thick and can play a role in shaping, the outer connecting film 21 is thin and is beneficial to covering the connecting rod 12 after deformation, and two sides of the outer connecting film can enter the inner side of the single body support 10 from the gap between two adjacent ring bodies 11 and are bonded with the inner film 22.

The drug coating includes a drug. The medicine is one or the combination of at least two of antithrombotic medicine, analgesic and anti-inflammatory medicine, anti-smooth muscle cell proliferation medicine, anti-vascular smooth muscle cell migration medicine, endothelium healing promoting medicine and hormone anti-inflammatory medicine. Wherein the anti-smooth muscle cell proliferation drug comprises one or a combination of at least two of rapamycin, paclitaxel, angiopeptin, mycophenolic acid, macrolide antibiotics, everolimus, cyclosporine A and methyl-RAPM.

Optionally, the drug coating further comprises a controlled release factor for controlling the release of the drug. The controlled release factor is degradable polymer or non-degradable polymer. The degradable polymer can be any one or the combination of at least two of gelatin, starch, hyaluronic acid, cellulose, chitosan, polylactic acid, polyglycolic acid, polycaprolactone, polylactide-caprolactone and polylactic acid-caprolactone; the non-degradable polymer may be any one of silicone rubber, polyurethane, poly (ethylene-vinyl acetate) copolymer, acrylic polymer, polyethylene, polypropylene, polyamide, polyvinylpyrrolidone, polyamides, polyethers, and parylene, or a combination of at least two thereof.

Therefore, the medicine coating formed by atomizing the medicine liquid containing the medicines and the controlled release factors into particles is used for repairing or treating a pathological change part on one hand, and on the other hand, the medical self-expanding stent 100 is implanted into a lumen of an organism, so that the organism is possibly stimulated to cause inflammation, the intima hyperplasia of the organism or scar tissues are generated, and the lumen of the organism is further narrowed, so that the medicines can inhibit secondary damage brought by the medical self-expanding stent 100 while repairing or treating, the harm to a human body is minimized, and the treatment comfort is improved.

A method of manufacturing a medical self-expanding stent 100 according to a second embodiment of the present invention, as shown in fig. 5 to 8, includes:

s1, preparing a plurality of the single stents 10 by cutting or weaving;

s2, sequentially sleeving the plurality of single supports 10 on the inner mold pipe 40, and inserting the positioning columns 60 on the inner mold pipe 40 for positioning, so that the plurality of single supports 10 are coaxially arranged and the axial distance is a preset distance;

specifically, as shown in fig. 5 and 7, the inner mold tube 40 is a hollow tube with two ends penetrating through, a plurality of positioning pillars 60 are detachably inserted on the inner mold tube 40, and one single-piece support 10 is supported and positioned by at least one positioning pillar 60, preferably by a pair of positioning pillars 60 symmetrically arranged;

s3, connecting a plurality of single stents 10 into a string by a plurality of flexible connectors 20 to obtain a medical self-expanding stent body;

s4, detaching the positioning column 60, and taking down the medical self-expansion bracket body;

s5, atomizing the medicine liquid containing the medicine into particles, and coating the particles on the outer surface of the medical self-expansion stent body to obtain the medical self-expansion stent.

In one embodiment, the flexible connector 20 includes an outer connecting membrane 21. Step S3 specifically includes: a plurality of outer mold pieces 50 provided with first air holes 52 are arranged along the circumferential direction of the inner mold tube 40, the outer connecting films 21 correspond to the outer mold pieces 50 one by one, one surface of each outer connecting film 21 is coated with an adhesive, the other surface of each outer connecting film 21 is adsorbed by the outer mold piece 50 through the first air holes 52 in a negative pressure mode, and the outer mold pieces 50 are moved to enable the outer connecting films 21 to be adhered to the outer sides of the plurality of monomer supports 10.

Further, in order to facilitate the removal of the medical self-expanding stent body, in step S4, the method further includes: the outer die 50 is removed.

In another embodiment, the flexible connector 20 includes an inner membrane 22. Before proceeding to step S2, step S11 is performed: a second air hole 41 is formed in the inner mold pipe 40, one surface of the inner film 22 is coated with an adhesive, and the other surface is adsorbed on the inner mold pipe 40 by negative pressure along the circumferential direction of the inner mold pipe 40 through the second air hole 41; further, step S3 specifically includes: the second air holes 41 blow air so that the inner film 22 moves toward the inner sides of the plurality of cell supports 10 and adheres to the inner sides of the plurality of cell supports 10.

In yet another embodiment, the flexible connector 20 includes an outer connecting membrane 21 and an inner membrane 22. Before proceeding to step S2, step S11 is performed: a second air hole 41 is formed in the inner mold pipe 40, one surface of the inner film 22 is coated with an adhesive, and the other surface is adsorbed on the inner mold pipe 40 by negative pressure along the circumferential direction of the inner mold pipe 40 through the second air hole 41; further, step S3 specifically includes: a plurality of outer die pieces 50 provided with first air holes 52 are arranged along the circumferential direction of the inner die tube 40, the outer connecting films 21 correspond to the outer die pieces 50 one by one, one surface of each outer connecting film 21 is coated with an adhesive, the other surface of each outer connecting film 21 is adsorbed by the outer die pieces 50 through the first air holes 52 in a negative pressure mode, and the outer die pieces 50 are moved to enable the two sides of the outer connecting films 21 and the two sides of the inner die 22 to be mutually attached and bonded.

Specifically, as shown in fig. 7, the second air holes 41 and the positioning pillars 60 are distributed at intervals in the circumferential direction of the inner mold pipe 40, and in order to ensure that the inner mold 22 can be well adsorbed, each inner mold 22 is adsorbed by the plurality of second air holes 41 arranged along the axial direction of the inner mold pipe 40, so that each inner mold 22 can extend along the axial direction of the inner mold pipe 40 on the outer surface of the inner mold pipe 40. In addition, as shown in fig. 5 and 6, the outer dies 50 are in a strip shape to match the shape of the outer connection film 21, each outer die 50 is provided with a plurality of first air holes 52 to better adsorb the outer connection film 21, and the plurality of outer dies 50 are spaced apart along the circumferential direction of the inner mold tube 40 such that the outer connection films 21 correspond to the inner films 22 one by one.

Further, in order to avoid the connecting rod 12 and prevent the outer connecting film 21 and the inner film 22 from damaging the connecting rod 12 during press bonding, the outer mold piece 50 is provided with an avoiding hole 51 for avoiding the connecting rod 12, so that when the outer mold piece 50 is moved, the outer mold piece 50 does not generate pressure on the connecting rod 12, and the connecting rod 12 can be prevented from being damaged. Specifically, as shown in fig. 5 and 6, the avoiding holes 51 correspond to the connecting rods 12 one by one, and at least one first air hole 52 is disposed between two adjacent avoiding holes 51.

Further, in order to ensure that the adhesive can be sufficiently softened and that both sides of the outer connecting film 21 and both sides of the inner film 22 are sufficiently attached so that the outer connecting film 21 and the inner film 22 can be well adhered, after performing step S3 and before performing step S4, step S31 is further performed: and raising the temperature of the inner mold tube 40 and the outer mold 50 to 400-450 ℃, and after the temperature is reached, respectively blowing inert gas with the temperature consistent with that of the inner mold tube 40 and the outer mold 50 through the second air hole 41 of the inner mold tube 40 and the first air hole 52 of the outer mold 50, so that the inner film 22 and the outer connecting film 21 are fully attached and kept for 10-30 min.

Further, in order to avoid scalding and to make the adhesive curable, after step S31, before step S4, step S32 is performed: the heating of the inner mold tube 40 and the outer mold piece 50 is stopped, and the second air holes 41 of the inner mold tube 40 and the first air holes 52 of the outer mold piece are both blown with cooling air for cooling.

Further, in order to facilitate the removal of the medical self-expanding stent body, in step S4, the method further includes: the outer die 50 is removed.

A method of implanting a medical self-expanding stent 100 according to a third aspect of the present invention comprises: compressing the medical self-expanding stent 100 into a delivery catheter; after the delivery catheter is moved to the lesion site, the medical self-expanding stent 100 is pushed out; the delivery catheter is withdrawn.

It should be noted that the medical self-expanding stent 100 may be relatively less compliant. Therefore, before the medical self-expandable stent 100 is implanted, the lesion site may be firstly expanded by the balloon catheter, then the balloon catheter is withdrawn, and finally the medical self-expandable stent 100 is implanted. The medical self-expandable stent 100 is mainly used for making the drug coating layer fully attached to the lesion part by utilizing the excellent compliance thereof, and has better repairing or treating effect on the lesion part. Unlike the existing balloon expandable stent and self-expandable stent, the medical self-expandable stent 100 does not forcibly open the lesion site by a mechanical action, but mainly plays a role in repair or treatment, so that the lumen can naturally recover the proper size.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

In the description of the present invention, "the first feature" and "the second feature" may include one or more of the features. In the description of the present invention, "a plurality" means two or more. In the description of the present invention, the first feature being "on" or "under" the second feature may include the first and second features being in direct contact, and may also include the first and second features being in contact with each other not directly but through another feature therebetween. In the description of the invention, "above", "over" and "above" a first feature in a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.