WO2022068550A1 - Venous valve stent and venous valve prosthesis - Google Patents

Abstract

A venous valve stent (1), which comprises a stent body (11) and at least one sinus cavity frame (12); the stent body (11) is a hollow cylindrical structure and can radially extend and retract; a window (115) is arranged on a side part of the stent body (11); each sinus cavity frame (12) has a fixed end and an opposing free end (1203); the fixed end is connected to an edge of a corresponding window (115); the free end (1203) is arranged in suspension; at least a portion of the sinus cavity frame (12) protrudes out from the stent body (11) in the radial direction of the stent body (11); a sinus area (102) is formed by an inner side of the sinus cavity frame (12), and the sinus area (102) is in communication with an inner part of the stent body (11) via the window (115). A venous valve prosthesis (100), which comprises a valve (2) and the venous valve stent (1), the valve (2) is fixed within the stent body (11), the valve (2) and at least a portion of the sinus cavity frame (12) are opposing in the radial direction of the stent body (11), and a side of the valve (2) away from the sinus cavity frame (12) is a free edge (202). This kind of structure can improve the reliability of a one-way guiding function, is able to prevent excessive stimulation of a blood vessel, and is also convenient to make.

Description

Venous valve stent and venous valve prosthesis technical field

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

Background technique

Venous surgery disease is a common disease in surgery, which mostly occurs in the lower extremities. Its main clinical manifestations are varicose veins, limb swelling, and skin dystrophic lesions in the boot area, such as dermatitis, pigmentation, and ulceration. The main pathological reason is that the venous valve loses the basic function of one-way opening under the action of pathogenic factors. Mild cases of venous disease hinder the ability to live and work, and severe cases can cause different degrees of disability. Therefore, the treatment of lower extremity venous valve disease has received increasing attention. At present, most of the clinical treatment of the disease is still conservative, such as drug therapy, pressure pump, etc., and surgical treatment such as femoral vein valve repair and reconstruction, etc., the clinical effect is not ideal. Especially in patients with severely damaged venous valves or congenital avalvular disease, venous valve transplantation seems to be the only option.

At present, the autologous valved iliac vein prosthesis or popliteal vein prosthesis is often used in clinic. The prosthesis is implanted into the venous blood vessel, and the stent of the prosthesis is attached to the blood vessel. The valve can open or close the channel to achieve a one-way opening function. However, in such a structure, local thrombus is easily formed between the valve and the stent, and the valve is also prone to degeneration and insufficient anti-reflux capability. In the long run, the effect is not ideal.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a venous valve stent and a venous valve prosthesis with better reliability.

In order to solve the above-mentioned technical problems, the present invention adopts the following technical solutions:

According to one aspect of the present invention, the present invention provides a venous valve stent, comprising a stent body and at least one sinus cavity frame; the stent body has a hollow cylindrical structure and can be radially expanded and contracted; the side portion of the stent body is provided with at least one fenestration; at least one sinus cavity frame is arranged corresponding to the at least one fenestration; each sinus cavity frame has opposite fixed ends and free ends; the fixed end is connected to a corresponding edge of the fenestration; the The free end is suspended; at least part of the sinus cavity frame protrudes outward from the stent body in the radial direction of the stent body; the inner side of the sinus cavity frame forms a sinus area, and the sinus area passes through the opening. The window communicates with the inside of the bracket body.

In some embodiments, along the radial direction of the stent body, the free end does not extend beyond the outermost portion of the rest of the sinus cage except the free end.

In some embodiments, the sinus lumen frame includes a first extension section and a second extension section, the second extension section is connected to the stent body through the first extension section, and the first extension section is connected to the stent body. The part where the second extension is connected forms the outermost part of the sinus cavity frame, the end of the second extension forms the free end, and the part where the first extension is connected with the stent body forms the fixing The distance between the outermost part and the central axis of the bracket body is greater than the distance between the fixed end and the central axis of the bracket body.

In some embodiments, the distance between the free end and the central axis of the stent body is smaller than the distance between the outermost portion and the central axis of the stent body.

In some embodiments, the second extension section extends in a curved line, and the curved line protrudes in a direction away from the bracket body.

In some embodiments, the second extension segment extends linearly.

In some embodiments, viewed on a plane passing through the central axis and the free end, the projection of the second extension on the plane is parallel to the central axis.

In some embodiments, the first extension section extends in a curved shape, and the curved line protrudes in a direction away from the bracket body.

In some embodiments, the first extension segment extends linearly.

In some embodiments, the sinus cavity rack includes a first strut and a second strut connected to the first strut, the first strut and the second strut are respectively connected to the stent body, The fixed end is formed at the part where the first support rod and the second support rod are connected to the bracket body respectively; the free end is formed at the connection part of the first support rod and the second support rod.

In some embodiments, the first strut and the second strut are directly connected.

In some embodiments, the sinus cage further includes a cross bar through which the first strut and the second strut are connected.

In some embodiments, in the direction from the first end to the second end, the part where the first strut and the bracket body are connected is connected to the second strut and the bracket body. The distance between the parts is greater than the distance between the part where the first support rod and the cross rod are connected and the part where the second support rod and the cross rod are connected.

In some embodiments, the included angle between the first strut and the second strut is 30°˜90°.

In some embodiments, the first strut and the second strut are symmetrical.

In some embodiments, at least one of the fenestrations is located in an axially central region of the stent body.

In some embodiments, the length of the sinus cage in the axial direction of the stent body is greater than half the length of the corresponding fenestration in the axial direction of the stent body.

In some embodiments, the bracket body includes at least two supporting bodies and a plurality of uprights, each of the uprights is connected to two of the supporting bodies at intervals, and the window is enclosed by the supporting bodies and the uprights become.

In some embodiments, each of the supporting bodies includes a plurality of wave circles that are connected in the axial direction; each wave circle has staggered wave crests and wave troughs along the circumferential direction, and in two adjacent wave circles, one of the wave circles is The peaks of the wave circles are connected with the valleys of the other wave circles to form a grid.

In some embodiments, the peaks of one of the supports are connected to the troughs of the other support through the posts.

In some embodiments, the uprights are linear and extend along the axial direction of the stent body.

In some embodiments, the bracket body is an integral structure, the entire outer peripheral wall thereof is in the shape of a mesh, and at least one of the openings is defined on the outer peripheral wall.

In some embodiments, the number of the fenestrations is multiple, and the multiple fenestrations are distributed along the circumference of the stent body; the sinus cavity frame is provided with a plurality of fenestrations, which are connected to the fenestrations in one-to-one correspondence. edge.

According to another aspect of the present invention, the present invention provides a venous valve prosthesis, comprising a valve and the above-mentioned venous valve stent; the valve is fixed in the stent body, and the valve is connected to the sinus cavity frame. At least partially opposite in the radial direction of the stent body; the valve has a free edge on the side of the valve facing away from the sinus region.

In some embodiments, the venous valve prosthesis further comprises a membrane covering the entire peripheral wall of the venous valve stent.

As can be seen from the above technical solutions, the present invention has at least the following advantages and positive effects: in the venous valve stent of the present invention, the stent body is a radially retractable cylindrical structure, so the venous valve stent can be in a contracted state before being implanted in the human body. It is accommodated in the delivery catheter, so that it can be delivered into the vein using the delivery catheter, and the surgical incision is small. After being implanted into the human body, the stent body is radially expanded and anchored in the blood vessel through self-expansion. The stent body can build a channel for blood to pass through, and can cooperate with the valve loaded in the venous valve stent to reconstruct the single venous valve. To guide function, and prevent venous blood reflux.

In particular, the venous valve stent has a sinus cavity frame that protrudes outward relative to the stent body, and a sinus area is formed inside the sinus cavity frame. The venous valve stent is loaded with a valve that can create eddy currents in the sinus region when blood flows back. Based on the vortex formed in the sinus area, when the blood flows downstream, the force of the downstream blood on the valve is balanced with the pressure generated by the vortex, so that the valve leaflet of the valve can be suspended without contacting the venous valve stent, reducing the stickiness of the valve leaflet. In addition, when the blood flows back, the backflowing blood impinges on the valve leaflets in suspension, which can more easily deform the valve leaflets in the direction of closing the blood flow channel, and quickly causes the valve leaflets to be deformed in the direction of closing the blood flow channel rather than impacting the valve leaflets that fit the venous valve stent. Close the channel to improve the sensitivity and reliability of the one-way open function. At the same time, under the action of the eddy current in the sinus area, the regurgitated blood can be guided to flow toward the heart again, which can effectively avoid the accumulation of blood and reduce the risk of local thrombosis.

Further, in this solution, the free end of the sinus cavity frame is suspended, so that the sinus cavity frame is elastic in the radial direction, which can avoid excessive stimulation of the blood vessel by the sinus cavity frame, reduce damage to the blood vessel, and prevent excessive intimal hyperplasia of the blood vessel. At the same time, the sinus cavity frame is connected to the fenestration edge of the stent body through its fixed end, and the structure and shape of the sinus cavity frame is not constrained by the stent body, which is convenient for the manufacture of the sinus cavity frame and the connection with the stent body. Afterwards, it is also convenient to maintain the structural form of the sinus cavity frame protruding from the stent body so as to maintain the stability of the sinus area.

Description of drawings

FIG. 1 is a schematic structural diagram of the first embodiment of the venous valve prosthesis of the present invention.

FIG. 2 is a front view of FIG. 1 .

FIG. 3 is a plan view of FIG. 1 .

FIG. 4 is a schematic view of the structure of FIG. 1 after removing the thin film.

FIG. 5 is a front view of the venous valve stent of FIG. 1 .

FIG. 6 is a side view of FIG. 5 .

FIG. 7 and FIG. 8 are schematic cross-sectional views of FIG. 1 after implantation in a human blood vessel, and the figures illustrate the open and closed states of the valve, respectively.

FIG. 9 is a schematic structural diagram of the second embodiment of the venous valve prosthesis of the present invention.

FIG. 10 is a plan view of FIG. 9 .

FIG. 11 is a schematic diagram of the internal structure of FIG. 9 .

FIG. 12 is a schematic structural diagram of the venous valve stent in FIG. 9 .

Fig. 13 is a schematic structural diagram of the third embodiment of the venous valve prosthesis of the present invention.

FIG. 14 is a plan view of FIG. 13 .

Fig. 15 is a schematic structural diagram of the fourth embodiment of the venous valve prosthesis of the present invention.

FIG. 16 is a schematic structural diagram of the venous valve stent in FIG. 15 .

17 is a schematic structural diagram of the fifth embodiment of the venous valve prosthesis of the present invention.

FIG. 18 is a front view of FIG. 17 .

Fig. 19 is a schematic structural diagram of the sixth embodiment of the venous valve prosthesis of the present invention.

FIG. 20 is a side view of the venous valve stent of FIG. 19 .

FIG. 21 is a front view of FIG. 20 .

Fig. 22 is a schematic structural diagram of the seventh embodiment of the venous valve prosthesis of the present invention.

FIG. 23 is a front view of FIG. 22 .

The reference numerals are explained as follows:

100/100a/100b/100c/100d/100e/100f, venous valve prosthesis; 500, blood vessel;

1/1a/1b/1c/1d/1e/1f, venous valve stent; 101/101a, channel; 102/102a/102b, sinus area;

11/11a/11c/11d/11e/11f, stent body; 111/111e, support body; 1111/1111f, wave circle; 1115, crest; 1116, trough; 1112, developing rod; 112/112a/112b/112e, Column; 115/115f, window opening;

12/12a/12b/12c/12d/12e/12f, sinus frame; 1201/1201c, first extension; 1202/1202c, second extension; 1203/1203c, free end; 1204/1204c, outermost part ; 121/121d/121e, first pole; 122/122d/122e, second pole; 123d, cross pole;

2/2a/2b, valve; 201, fixed edge; 202/202a, free edge; 21, valve body; 22, leaflet;

3/3a/3d, film.

Detailed ways

Exemplary embodiments embodying the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different embodiments without departing from the scope of the present invention, and the descriptions and drawings therein are essentially used for illustration rather than limitation this invention.

The invention provides a venous valve stent and a venous valve prosthesis, which are used for the interventional treatment of venous valve insufficiency. The venous valve prosthesis includes the venous valve stent and a valve connected within the venous valve stent. The venous valve prosthesis is delivered into the diseased vein by means of percutaneous puncture through a delivery catheter, and is precisely positioned and released, so as to prevent venous blood backflow.

For ease of presentation, it is defined herein that "proximal" refers to the end close to the location of the heart, and "distal" refers to the end that is remote from the location of the heart. The normal direction of blood flow in human veins is toward the heart, that is, from the distal end to the proximal end.

The following is a detailed introduction through several embodiments of the venous valve prosthesis.

For the first embodiment, please refer to the structures and usage states shown in FIG. 1 to FIG. 8 .

Referring first to FIGS. 1 to 4 , the venous valve prosthesis 100 of this embodiment includes a venous valve stent 1 , a valve 2 and a membrane 3 .

Among them, the venous valve stent 1 is a bare stent, which forms a channel 101 for blood to pass through the distal end and the proximal end in the unfolded state. In this embodiment, the side of the venous valve stent 1 is also formed with a convex sinus region 102 . The film 3 can be sutured, bonded or thermocompressed on the inner side of the venous valve stent 1, or can be sutured, bonded or thermocompressed on the outside of the venous valve stent 1, covering the entire peripheral wall of the venous valve stent 1, the film 3 and the venous valve stent 1. The valve stent 1 is combined into a whole, so as to increase the contact area between the venous valve prosthesis 100 and the human blood vessel. The valve 2 is a single-valve structure, located inside the venous valve stent 1 , connected and fixed with the venous valve stent 1 , and covers at least part of the sinus region 102 to function as one-way conduction.

Referring to FIGS. 5 and 6 , the venous valve stent 1 includes a stent body 11 and a sinus cavity frame 12 connected to the side of the stent body 11 . The bracket body 11 has a hollow cylindrical structure as a whole, so a channel 101 can be formed in its interior. A fenestration 115 is provided on the side of the stent body 11; the sinus cavity frame 12 is connected to the edge of the fenestration 115 and protrudes radially outward relative to the stent body 11, thereby forming the sinus region 102 inside the sinus cavity frame 12, The sinus region 102 communicates with the channel 101 inside the stent body 11 through the fenestration 115 .

The bracket body 11 of this embodiment mainly includes two supporting bodies 111 arranged at intervals and a plurality of uprights 112 connected between the two supporting bodies 111 .

The support body 111 is a self-expanding structure, and is in the shape of a cylindrical closed-loop in the circumferential direction. The two support bodies 111 are arranged coaxially and are opposite to each other along the axial direction.

Each support body 111 has a plurality of wave rings 1111 axially connected to each other. Each wave circle 1111 has crests 1115 and troughs 1116 that are staggered in the circumferential direction. The crest 1115 is toward the proximal end, and the trough 1116 is toward the distal end. The crests 1115 and troughs 1116 of two adjacent wave circles 1111 are connected to form a grid.

The adjacent wave crests 1115 and adjacent wave troughs 1116 of each wave ring 1111 can be close to or away from each other, so that the support body 111 and the entire stent body 11 can expand and contract in the radial direction. The stent body 11 is in a contracted state before being implanted into the human body to be accommodated in the delivery catheter, and after being implanted into the human body, it expands and anchors at a predetermined position of the human blood vessel through self-expansion. In particular, the anchoring is mainly achieved by combining the support body 111 with the human blood vessel after radial expansion.

Specifically, as shown in FIG. 5 , each support body 111 has two corrugated circles 1111 . Each wave ring 1111 can be regarded as a closed-loop structure extending in a Z-shape from a rod. Each wave circle 1111 has eight wave crests 1115 and eight wave troughs 1116 arranged in a circumferentially staggered manner. The wave troughs 1116 of the wave ring 1111 at the proximal end are connected with the wave crests 1115 of the wave ring 1111 at the far end, forming eight successively connected diamond-shaped grids along the circumferential direction of the support body 111 . The two wave rings 1111 form a circumferential closed-loop structure, so that the venous valve stent 1 has high radial support force and better anchoring effect.

Two developing rods 1112 protrude from the support body 111 located at the proximal end toward the proximal end, and two developing rods 1112 protrude toward the distal end from the support body 111 located at the distal end. The two developing rods 1112 on each supporting body 111 are circumferentially opposite, and the four developing rods 1112 are staggered circumferentially. A developing mark can be set on the developing rod 1112 to facilitate displaying the position of the venous valve stent 1 during implantation. The developing mark is set on the developing rod 1112 by using developing material, and can be set in a dot shape, a line shape, or the like. In this embodiment, the end of the developing rod 1112 is annular, which can be used for pressing dot-shaped developing marks.

Each of the uprights 112 is linear and extends along the axial direction of the bracket body 11 . The plurality of uprights 112 are circumferentially spaced around the central axis L of the support body 111 . The cylindrical structure formed by the plurality of uprights 112 is coaxial with the support body 111 .

Two ends of the upright column 112 are respectively connected with the wave crests 1115 and the wave troughs 1116 opposite to the two support bodies 111 . That is, the proximal end of the upright post 112 is connected to the trough 1116 of the proximal support body 111 , and the distal end of the upright post 112 is connected to the corresponding wave crest 1115 of the distal support body 111 .

Specifically, in this embodiment, the number of the uprights 112 is four, which are evenly arranged in the circumferential direction between the two support bodies 111 , and one upright post 112 is connected every at least one wave crest 1115 or wave trough 1116 along the circumferential direction. The interval between two adjacent uprights 112 forms a window 115 , and the distance between the two supports 111 or the length of the uprights 112 constitutes the axial length of the window 115 .

The structure of the stent body 11 can provide good radial support force by using the support bodies 111 located at both ends in a closed-loop structure, and has the advantage of strong anchoring force, which is convenient for fitting and fixing with human blood vessels. The upright post 112 in the middle increases the axial rigidity of the venous valve stent 1 , which facilitates the venous valve stent 1 to maintain the stability of the shape. Preferably, the width of the upright post 112 is greater than the width of the rod of the wave ring 1111 of the support body 111 .

Still referring to FIGS. 5 and 6 , the sinus cavity frame 12 is correspondingly connected to the opening 115 of the stent body 11 . The sinus frame 12 includes a first strut 121 and a second strut 122 . The first end, ie, the distal end, of the first support rod 121 is separated from the first end, ie, the distal end, of the second support rod 122 , and each is connected to a post 112 that defines the window 115 . The second end, ie, the proximal end, of the first strut 121 is connected to the second end, ie, the proximal end, of the second strut 122, and forms a free end 1203 of the sinus frame 12; the free end 1203 is overhanging from the The outer side of the bracket body 11 . The space enclosed between the first strut 121 , the second strut 122 and the two uprights 112 to which they are connected forms the sinus area 102 .

As shown in FIG. 5 , in this embodiment, in the direction from the distal end to the proximal end, the first strut 121 and the second strut 122 gradually approach each other. The proximal end of the first support rod 121 and the proximal end of the second support rod 122 are directly connected, and the first support rod 121 and the second support rod 122 are connected to form a V-shape. Preferably, the first support rod 121 and the second support rod 122 are symmetrical. The included angle α formed by the first support rod 121 and the second support rod 122 preferably ranges from 30° to 90°. In this embodiment, the distal ends of the first support rod 121 and the second support rod 122 are respectively connected to the distal ends of the two uprights 112 , so that the first support rod can be held by the radial support force of the support body 111 . The relative position of the rod 121 and the second support rod 122 .

In the direction from the distal end to the proximal end along the axial direction of the stent body 11, the sinus cavity frame 12 starts at the distal end of the post 112, and then extends proximally beyond the midpoint of the post 112, but is different from the one located at the proximal end. There is a space between the support bodies 111 . That is, the length of the sinus cavity frame 12 in the axial direction of the stent body 11 is greater than half of the axial length of the fenestration 115 , which is convenient for guiding the flow of blood and also facilitating the arrangement of the membrane 3 .

Referring to FIG. 6 , in the direction from the distal end to the proximal end along the axial direction of the stent body 11 , the sinus cavity frame 12 relative to the stent body 11 gradually extends outwardly and then gradually inwardly. That is, the free end 1203 of the sinus cavity frame 12 is bent toward the inner side of the stent body 11 , so that the free end 1203 of the sinus cavity frame 12 does not exceed the outermost part 1204 of the sinus cavity frame 12 along the radial direction of the stent body 11 . , which can effectively prevent the free end 1203 of the sinus cavity frame 12 from damaging the vascular tissue when implanted into a human blood vessel.

For convenience of description, along the axial direction of the stent body 11 , the sinus cavity frame 12 is divided into a first extension section 1201 near the distal end and a second extension section 1202 near the proximal end. In the direction from the distal end to the proximal end, the distance Di from each position of the first extension section 1201 to the central axis L of the stent body 11 gradually increases, and the distance from each position of the second extension section 1202 to the central axis L of the stent body 11 Dj gradually decreases. The distal end of the first extension section 1201 is connected to the stent body 11, and the part where the first extension section 1201 and the second extension section 1202 are connected constitutes the outermost part 1204 of the sinus frame 12 relative to the stent body 11. The second extension The end of the segment 1202 is the free end 1203 . The sinus cavity frame 12 is curved in an arc shape as a whole, so that the sinus cavity frame 12 will not form an obvious bending edge or a bending edge at the junction of the first extension section 1201 and the second extension section 1202, which can further prevent When implanted into a human blood vessel, the sinus cavity scaffold 12 damages the blood vessel tissue.

From the appearance of the venous valve stent 1, the outer diameter of the support body 111 of the stent body 11 is D1, and the distance between the outermost part 1204 of the sinus cavity frame 12 and the side wall on the opposite side of the support body 111 is D2 , D2>D1. The difference between D2 and D1 is the maximum distance that the sinus cavity frame 12 protrudes outward.

Further, in the present embodiment, in the direction from the distal end to the proximal end, the increasing speed of the distance from the first extending section 1201 to the central axis L gradually decreases, while the distance between the second extending section 1202 and the central axis L decreases the speed. gradually become larger.

That is to say, the first support rod 121 and the second support rod 122 are both curved in the range of the first extension section 1201 and the range of the second extension section 1202 , and the curves of the first extension section 1201 and the second extension section 1202 are curved. Both are protruding in the direction away from the bracket body 11 , which can improve the deformation resistance of the first support rod 121 and the second support rod 122 . And when implanted into a human blood vessel, the bending directions of the first strut 121 and the second strut 122 are both protruding toward the blood vessel, and the first strut 121 and the second strut 122 can withstand greater damage caused by the blood vessel wall. The radial pressure is easy to maintain the stability of the shape.

It can be understood that, in other feasible structures, the first extension section 1201 and the second extension section 1202 may also both extend in a straight line, and in the direction from the distal end to the proximal end, the first extension section 1201 reaches the central axis L The increasing speed of the distance remains unchanged, and the decreasing speed of the distance between the second extension section 1202 and the central axis L also remains unchanged. That is, the first support rod 121 and the second support rod 122 are both straight-section structures in the range of the first extension section 1201 and the range of the second extension section 1202 . In addition, when the first extension section 1201 extends in a curve shape, the second extension section 1202 may extend in a straight line. When the first extension section 1201 extends in a straight line, the second extension section 1202 may also extend in a curve shape.

The structure of the sinus cavity frame 12 in this embodiment is simple and easy to manufacture. In addition, the number of structural parts of the sinus cavity frame 12 is small, and the metal coverage rate is small, so as to avoid intimal hyperplasia caused by excessive stimulation of human blood vessels. Using the sinus region 102 formed on the inner side of the sinus cavity frame 12 , a vortex can be formed in the sinus region 102 when the blood flows back, which is beneficial to the pressure balance of the valve 2 .

Based on the structure of the venous valve stent 1 , referring to FIG. 4 again, the valve 2 is located in the stent body 11 of the venous valve stent 1 , aligned with the sinus cavity frame 12 , and covers at least a part of the sinus region 102 . At least part of the valve 2 and the sinus cavity frame 12 are opposite to each other in the radial direction of the stent body 11 , that is, there is at least one cross section perpendicular to the central axis of the stent body 11 which passes through the valve 2 and the sinus cavity frame 12 at the same time. The valve 2 has a substantially V-shaped fixing edge 201, and the fixing edge 201 is fixed to the stent body 11 or the membrane 3 by, for example, suturing or bonding.

The V-shaped apex of the fixed edge 201 is located on the side where the sinus cavity frame 12 is located, is close to the sinus cavity frame 12, and is closer to the distal end relative to the sinus cavity frame 12. For example, the V-shaped apex of the fixed edge 201 can be fixed at the distal end. On a wave crest 1115 of the support body 111 , the wave crest 1115 is located between the two uprights 112 to which the sinus cavity frame 12 is connected.

In the direction from the distal end to the proximal end, the fixed edge 201 starts from the apex of the V shape and extends obliquely along the inner wall of the stent body 11 toward the opposite side to the proximal end of the sinus cavity frame 12, so that if shown in FIG. 2 From the front view of (the valve 2 is obscured and not shown in FIG. 2 ), the valve 2 covers a portion of the sinus region 102 . The length of the valve 2 in the axial direction of the stent body 11 may be, for example, beyond the sinus cavity frame 12 .

The side of the valve 2 facing away from the sinus cavity frame 12 is not fixed with the stent body 11 , so a free edge 202 is formed, and both ends of the free edge 202 are connected to the V-shaped opening of the fixed edge 201 . By changing the position of the free edge 202 , the valve 2 can close or open the channel 101 in the stent body 11 .

When the blood flows from the proximal end to the distal end of the channel 101, the blood passes through the sinus region 102 and pushes the valve 2 to the inner wall of the stent body 11 on the opposite side of the sinus cavity frame 12, so that the free edge 202 of the valve 2 and the membrane on the stent body 11 are connected. 3, the blood will not be able to flow further distally through the valve 2, and the channel 101 is closed. When blood flows from the distal end to the proximal end, the blood will push the valve 2 to the side where the sinus region 102 is located, at this time, the free edge 202 of the valve 2 is separated from the membrane 3, and the channel 101 is opened. It should be noted that when the valve 2 is pushed to the inner wall of the stent body 11 on the opposite side of the sinus cavity frame 12, there may be a slight gap between the free edge 202 and the membrane 3. At this time, the free edge 202 does not fit the membrane 3, so that the The risk of adhesion between the free edge 202 and the stent body 11 or the membrane 3 is reduced, and the small gap between the free edge 202 and the membrane 3 does not affect the valve 2 to block most of the backflow blood flow.

The valve 2 may include a valve body 21 and a valve leaflet 22 . The valve body 21 constitutes the above-mentioned fixed edge 201 and is connected and fixed with the venous valve stent 1. The valve leaflet 22 is connected between the valve bodies 21. When the valve leaflet 22 is expanded into a plane, the area is greater than the area enclosed by the fixed edge 201. The part of the edge 22 that is not combined with the valve body 21 constitutes a free edge 202 . The middle part of the valve leaflet 22 is beyond the plane where the valve body 21 is located, and a sinus cavity is formed between the valve leaflet 22 and the valve body 21 . The valve leaflet 22 can be deformed, and through the deformation of the valve leaflet 22, the position of the free edge 202 of the valve leaflet 22 can be changed, so as to realize the switching of the closed state and the open state.

Based on the existence of the valve 2, a one-way passage of blood when passing through the venous valve stent 1 can be constructed, and the valve 2 is used as a one-way valve.

Both the valve 2 and the membrane 3 are made of different biological materials or medical polymer materials, such as polyester, polytetrafluoroethylene, polyurethane, medical silicone, polyester, biological valve, pericardium or other implantable medical materials.

Referring to FIG. 7 , when the venous valve prosthesis 100 of the present embodiment is implanted into a human blood vessel 500 , the venous valve stent 1 is attached to the intima of the blood vessel 500 . Normally, blood flows from the distal end of the venous valve prosthesis 100 to the proximal end and into the heart. In some cases, when blood flows back, the valve 2 moves toward the opposite side of the sinus cavity frame 12 under the impact of the blood flow under the action of the backflow blood flow from the proximal end to the distal end, thereby closing the channel in the stent body 11 101, effectively avoiding the backflow of blood at the distal end. At this time, the eddy current formed in the sinus region 102 makes the backflow blood flow to the proximal end again, so as to avoid blood retention and accumulation at the root of the valve 2, thereby avoiding the formation of local thrombus.

Referring to FIG. 8 , during the flow of downstream blood flow in the blood vessel 500, the area of the sinus region 102 covered by the valve 2 forms a vortex, which is beneficial to the pressure balance of the valve 2. At this time, the valve leaflet 22 of the valve 2 is in the Under the combined action of eddy current and downstream blood flow, it is in a suspended state, and does not adhere to the stent body 11, the membrane 3 or the inner wall of the blood vessel 500, thereby reducing the risk of adhesion, so as to ensure that the valve 2 continues to have a one-way closing function, In addition, the formed vortex can also avoid the risk of thrombosis due to blood flow retention at the root of the valve 2 .

Based on the above description, in the venous valve prosthesis 100 of the present embodiment, since the sinus region 102 is formed on the venous valve stent 1, the existence of the sinus region 102 enables the backflowing blood to form a vortex in the sinus region 102. When the blood flows downstream, the pressure balance generated by the eddy current in the sinus region 102 enables the valve 2 to open the channel 101 while the leaflets 22 of the valve 2 are suspended in the channel 101 without sticking to the venous valve stent 1 or membrane 3 This reduces the risk of failure of the valve leaflets 22 due to adhesion. In addition, when there is blood reflux, the valve 2 can more easily close the channel 101 by the blood flow impinging on the suspended valve leaflet 22 than by impinging on the venous valve stent 1 or the membrane 3 .

Further, the stent body 11 of the venous valve stent 1 is a radially expandable structure, and has a small size before being implanted into the blood vessel 500, and the surgical trauma is small. The stent body 11 adopts the support body 111 with a closed-loop structure at both ends, which has the advantages of high radial support force and strong anchoring force. Uniform force is applied to the intima of the blood vessel 500 , thereby reducing stimulation to the intima of the blood vessel 500 , and preventing excessive proliferation of the intima of the blood vessel 500 . The upright column 112 located in the middle of the stent body 11 increases the axial stiffness of the venous valve stent 1, so that the stent body 11 part of the load valve 2 does not change in diameter due to factors such as muscle pump and pressure gradient changes. The entire structure of the venous valve stent 1 exhibits greater rigidity, and the venous valve stent 1 always maintains a fixed shape after implantation, and does not affect the valve body 21 of the valve 2 and thus the function of the valve leaflets 22 due to changes in the transmural pressure of the blood vessel 500 .

The sinus cavity frame 12 of the venous valve stent 1 forms a sinus region 102 on the side of the stent body 11 , forming a structural advantage in line with hydrodynamics, so that blood does not generate thrombus at the valve 2 . In particular, the sinus cavity frame 12 adopts a design with a suspended free end 1203 to have elasticity in the radial direction, which can avoid excessive stimulation of the blood vessel 500 by the sinus cavity frame 12 . And after implantation into the human body, since the free end 1203 is suspended, the support body 111 closer to the proximal end of the sinus cavity frame 12 will not constrain the free end 1203, and the sinus cavity frame 12 can be more easily maintained at least partially outside. Convex the structural form of the stent body 11 , thereby maintaining the stability of the sinus region 102 .

Meanwhile, the sinus cavity frame 12 of this embodiment is formed by connecting the first support rod 121 and the second support rod 122 to the support body 11 , with few structural parts and a simple structure. In actual manufacture, the stent body 11 and the sinus cavity frame 12 can be manufactured separately first, and then the two are connected as a whole, which is convenient for manufacture. In addition, the sinus cavity frame 12 is connected with the upright post 112, and the sinus cavity frame 12 with a simple structure is matched with the upright posts 112 arranged at intervals, so that the venous valve stent 1 also has a large operating space for the connection of the valve 2, and the metal coverage rate is small, which effectively reduces the Stimulation of blood vessel 500 intima.

It can be understood that, in other structures not shown, the sinus cavity frame 12 is not limited to adopt the structural form composed of the first strut 121 and the second strut 122 in this embodiment. Based on the concept of the present invention, the sinus cavity frame 12 only needs to meet the following conditions: one end is a fixed end that is fixedly connected to the bracket body 11 , the opposite end is a free end 1203 that is suspended in the air, and the sinus cavity frame 12 is at least partially in the bracket body. The radial direction of 11 protrudes outward from the stent body 11 to form a sinus region 102 on the inner side of the sinus cavity frame 12 . Wherein, in this embodiment, the portions where the proximal end portion of the first support rod 121 and the proximal end portion of the second support rod 122 are respectively connected to the bracket body 11 constitute fixed ends. In fact, since one end of the sinus cavity frame 12 is fixed and the other end is a free end, the overall structural shape of the sinus cavity frame 12 is not constrained by the stent body 11 or specifically the fenestration 115 of the stent body 11 . In practice, the structural form of the sinus cavity frame 12 is flexibly set, which facilitates the manufacture of the sinus cavity frame 12 and the connection with the stent body 11 .

The venous valve stent 1 in this embodiment can be manufactured by laser engraving of NiTi alloy. In some embodiments, the total length L1 of the venous valve stent 1 (excluding the length of the developing rod 1112 ) may be 15 mm˜30 mm, the diameter D1 of the support body 111 may be 5 mm˜30 mm, and the maximum diameter D2 where the sinus cavity frame 12 is located is smaller than The diameter D1 of the support body 111 protrudes by 2.5 mm.

The thickness of the venous valve stent 1 can be designed to be 0.35mm, the width of each rod in the support body 111 can be designed to be 0.35mm, and the width of each rod in the upright post 112 and the sinus cavity frame 12 can be designed to be 0.6mm, so that the venous valve stent 1 has Better radial support and axial stiffness.

For the second embodiment, refer to the structures shown in FIGS. 9 to 12 .

The difference between the venous valve prosthesis 100a of this embodiment and the first embodiment is that the venous valve stent 1a of the venous valve prosthesis 100a has a plurality of sinus regions 102a, and in this embodiment, there are two sinus regions 102a . Correspondingly, the valve 2a has a double valve structure. The membrane 3a covers the two sinus regions 102a.

The venous valve stent 1a has two sinus cavity frames 12a disposed opposite to each other, and the two sinus cavity frames 12a respectively protrude outward relative to the stent body 11a, so that the directions of the two sinus regions 102a are also opposite.

The two valves 2a are sewn between the two sinus frames 12a. The free edges 202a of the two valves 2a meet in the middle of the venous valve stent 1a.

When blood flows back, the two valves 2a are arched, and the free edges 202a of the two valves 2a are abutted together to close the channel 101a and prevent the backflow blood from passing through. Eddy currents are formed in the two sinus regions 102a, respectively, so as to promote blood to return to the proximal end and avoid blood accumulation.

When the downstream blood passes through, the blood flow impacts the valve 2a, the free edges 202a of the two valves 2a are separated, and the channel 101a is opened to allow the blood to flow to the proximal end normally.

In this embodiment, the structure of two sinus cavity stents 12a is adopted to effectively balance the open state of the valve 2a, and eddy currents are formed on both sides of the venous valve stent 1a to avoid local thrombosis caused by blood accumulation.

Compared with the four uprights 112 in the first embodiment, in this embodiment, an additional upright 112a is provided in the interval between the two uprights 112a that are not connected to the sinus cavity frame 12a, that is, the stent body of this embodiment 11a has a total of six uprights 112a, increasing the radial support strength. Of course, when the radial support strength is sufficient, the extra two uprights 112a can also be omitted.

The second embodiment is described by taking a double valve as an example. Based on the concept of the present invention, the venous valve prosthesis can also have three or more sinus regions. Correspondingly, there are three-lobed and multi-lobed structures.

For the third embodiment, refer to the structures shown in FIGS. 13 and 14 .

This embodiment is a further extension of the above-mentioned second embodiment. In the venous valve prosthesis 100b of this embodiment, the venous valve stent 1b is provided with four sinus cavity frames 12b, and the four sinus cavity frames 12b are along the circumferential direction of the venous valve stent 1b Evenly distributed, they are respectively arranged between two adjacent uprights 112a. Accordingly, four sinus regions 102b are formed in the venous valve stent 1b. The number of valves 2b is also corresponding to four, which are arranged one by one relative to the sinus region 102b.

For the fourth embodiment, refer to the structures shown in FIGS. 15 and 16 .

The venous valve prosthesis 100c of this embodiment is different from the first embodiment in that the structure of the sinus cavity frame 12c of the venous valve stent 1c is different.

In this embodiment, the free end 1203c of the sinus cavity frame 12c is not bent toward the inner side of the stent body 11c, instead, the sinus cavity frame 12c is divided into a first extension section 1201c near the distal end and a first extension section 1201c near the distal end along the axial direction of the stent body 11c. For the second extension section 1202c at the proximal end, in the direction from the distal end to the proximal end, the distance from the first extension section 1201c to the central axis L of the stent body 11c gradually increases, and the distance from the second extension section 1202c to the central axis L remains constant. 16, viewed on a plane passing through the central axis L and the free end 1203c, the projection of the second extension 1202c on the plane is parallel to the central axis L.

In this embodiment, the free end 1203c of the sinus cavity frame 12c still does not extend beyond the outermost portion 1204c of the remaining part of the sinus cavity frame 12c except for the free end 1203c in the radial direction of the stent body 11c.

The distance from the second extension section 1202c to the central axis L remains unchanged. When the venous valve prosthesis 100c is implanted into a human blood vessel, the second extension section 1202c can avoid local stress concentration on the blood vessel wall and relieve the convexity of the sinus cavity frame 12c The pressure on the blood vessel wall to avoid excessive pressure on the blood vessel wall due to local stress concentration.

For the fifth embodiment, refer to the structures shown in FIGS. 17 and 18 .

The difference between the venous valve prosthesis 100d of the present embodiment and the first embodiment is that the structure of the sinus cavity frame 12d of the venous valve stent 1d is different.

In this embodiment, the sinus cavity frame 12d further includes a cross bar 123d. The first support bar 121d and the second support 122d are connected by the cross bar 123d. The cross bar 123d extends along the circumferential direction of the support body 11d. The proximal end portion of the first strut 121d and the proximal end portion of the second strut 122d are respectively connected.

The arrangement of the cross bar 123d can increase the supporting area of the membrane 3d, and ensure the firm performance of the part of the membrane 3d covering the sinus area under the impact of eddy currents. In addition, the transverse rod 123d can weaken the sharpness of the free end of the sinus cavity frame 12d, and the increase of the transverse area thereof can avoid damage to the vessel wall during implantation.

For the sixth embodiment, refer to the structures shown in FIGS. 19 to 21 .

The venous valve prosthesis 100e of this embodiment is different from the first embodiment in that the connection position of the sinus cavity frame 12e and the stent body 11e in the venous valve stent 1e is different.

In this embodiment, the first strut 121e and the second strut 122e of the sinus cavity frame 12e are not connected to the ends of the upright post 112e, but are connected to the middle area of the upright post 112e.

Wherein, there is a distance S1 between the free end 1203e of the sinus cavity frame 12e and the support body 111e near the proximal end, and the proximal end of the first strut 121e and the proximal end of the second strut 122e are separated from the proximal end of the first strut 121e The support body 111e has a distance S2, and in this embodiment, S1 and S2 are equal.

For the seventh embodiment, refer to the structures shown in FIG. 22 and FIG. 23 .

The venous valve prosthesis 100f of this embodiment is different from the first embodiment in that the structure of the stent body 11f of the venous valve stent 1f is different.

In this embodiment, the support body 11f is an integrated mesh support, and the entire outer peripheral wall thereof is mesh-shaped, and no longer has the upright column 112 as in the first embodiment. A substantially rectangular notch is formed on the side of the bracket body 11f to form a window 115f, and the window 115f is located in the middle area of the bracket body 11f in the axial direction of the bracket body 11f. The sinus cavity frame 12f is provided at the opening 115f.

The support body 11f includes a plurality of annular wave rings 1111f, and the plurality of annular wave rings 1111f are arranged in sequence along the axis of the support body 11f and axially connect to form a grid. And the opening 115f may be formed by cutting on the bracket body 11f.

This embodiment adopts the stent body 11f of an integrated mesh structure, which has better radial contraction and expansion performance. The window 115f provided on the side of the stent body 11f can improve the overall compliance performance of the venous valve stent 1f. The venous valve stent 1f can be bent at the fenestration 115f, so that it can pass through the circuitous and complicated vascular access more easily, and has higher flexibility than the first embodiment.

While the present invention has been described with reference to several exemplary embodiments, it is to be understood that the terminology used is of description and illustration, and not of limitation. Since the invention can be embodied in many forms without departing from the spirit or spirit of the invention, it is to be understood that the above-described embodiments are not limited to any of the foregoing details, but are to be construed broadly within the spirit and scope defined by the appended claims Therefore, all changes and modifications that come within the scope of the claims or their equivalents should be covered by the appended claims.

Claims (25)

1. A venous valve stent, comprising:

   a bracket body, which has a hollow cylindrical structure and can be radially extended and retracted; at least one opening window is provided on the side of the bracket body; and

   At least one sinus cavity frame is disposed corresponding to the at least one fenestration; each sinus cavity frame has opposite fixed ends and free ends; the fixed end is connected to a corresponding edge of the fenestration; the free end Suspended setting; at least part of the sinus cavity frame protrudes outward from the stent body in the radial direction of the stent body; the inner side of the sinus cavity frame forms a sinus area, and the sinus area is connected to the fenestration through the fenestration. The inside of the bracket body is communicated.
2. The venous valve stent according to claim 1, wherein in the radial direction of the stent body, the free end does not exceed the outermost part of the remaining part of the sinus cavity frame except the free end.
3. The venous valve stent according to claim 2, wherein the sinus cavity stent comprises a first extension section and a second extension section, and the second extension section is connected to the stent body through the first extension section, The part where the first extension section and the second extension section are connected forms the outermost part of the sinus cavity frame, the end of the second extension section forms the free end, and the first extension section and the The part where the bracket body is connected forms the fixed end, and the distance between the outermost part and the central axis of the bracket body is greater than the distance between the fixed end and the central axis of the bracket body.
4. The venous valve stent according to claim 3, wherein the distance between the free end and the central axis of the stent body is smaller than the distance between the outermost part and the central axis of the stent body.
5. The venous valve stent according to claim 4, wherein the second extension section extends in a curved manner, and the curve protrudes in a direction away from the stent body.
6. The venous valve stent according to claim 4, wherein the second extension section extends linearly.
7. The venous valve stent according to claim 3, wherein, viewed on a plane passing through the central axis and the free end, the projection of the second extending section on the plane is parallel to the central axis.
8. The venous valve stent according to claim 3, wherein the first extension section extends in a curved manner, and the curve protrudes in a direction away from the stent body.
9. The venous valve stent according to claim 3, wherein the first extension section extends linearly.
10. The venous valve stent according to claim 1, wherein the sinus cavity stent comprises a first strut and a second strut connected to the first strut, the first strut and the second strut The support rods are respectively connected to the bracket body, the parts where the first support rod and the second support rod are respectively connected to the support body form the fixed end, and the first support rod and the second support rod are connected The part forms the free end.
11. The venous valve stent according to claim 10, wherein the first strut and the second strut are directly connected.
12. The venous valve stent according to claim 10, wherein the sinus cavity stent further comprises a cross bar, and the first strut and the second strut are connected by the cross bar.
13. The venous valve stent according to claim 12, wherein the distance between the part where the first strut is connected to the stent body and the part where the second strut is connected to the stent body is greater than The distance between the part where the first support rod and the cross rod are connected and the part where the second support rod and the cross rod are connected.
14. The venous valve stent according to claim 10, wherein the included angle between the first strut and the second strut is 30°˜90°.
15. The venous valve stent according to claim 10, wherein the first strut and the second strut are symmetrical.
16. The venous valve stent according to any one of claims 1-15, characterized in that, at least one of the fenestrations is located in the axial middle region of the stent body.
17. The venous valve stent according to claim 16, wherein the length of the sinus cavity frame in the axial direction of the stent body is greater than the length of the corresponding fenestration in the axial direction of the stent body. half.
18. The venous valve stent according to claim 16, wherein the stent body comprises at least two support bodies and a plurality of uprights, each of the uprights is connected to the two spaced apart support bodies, and the window is formed by The support body and the upright column are enclosed.
19. The venous valve stent according to claim 18, wherein each of the supporting bodies comprises a plurality of corrugated circles that are connected in the axial direction; Among the two wave circles, the wave crest of one of the wave circles is connected with the wave trough of the other wave circle to form a grid shape.
20. The venous valve stent according to claim 19, wherein the wave crest of one support body is connected to the wave trough of the other support body through the post.
21. The venous valve stent according to claim 18, wherein the upright column is linear and extends along the axial direction of the stent body.
22. The venous valve stent according to claim 16, wherein the stent body is an integral structure, the entire peripheral wall thereof is in the shape of a mesh, and at least one of the fenestrations is provided on the peripheral wall.
23. The venous valve stent according to any one of claims 1-15, wherein the number of the fenestrations is multiple, and the multiple fenestrations are distributed along the circumference of the stent body; the sinus cavity is erected There are a plurality of them, which are connected to the edge of the window in one-to-one correspondence.
24. A venous valve prosthesis, characterized in that it comprises a valve and the venous valve stent according to any one of claims 1-23; the valve is fixed in the stent body, and the valve is connected to the sinus cavity frame At least part of the valve is opposite in the radial direction of the stent body; the valve has a free edge, the free edge is located on the side of the valve away from the sinus cavity frame.
25. The venous valve prosthesis according to claim 24, wherein the venous valve prosthesis further comprises a membrane covering the entire peripheral wall of the venous valve stent.

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