CN111053629A

CN111053629A - Heart valve support and prosthesis thereof

Info

Publication number: CN111053629A
Application number: CN201811205699.XA
Authority: CN
Inventors: 刘世红; 赵婧; 陈国明; 李�雨
Original assignee: Shanghai Microport Cardioflow Medtech Co Ltd
Current assignee: Shanghai Microport Cardioflow Medtech Co Ltd
Priority date: 2018-10-17
Filing date: 2018-10-17
Publication date: 2020-04-24
Also published as: WO2020078349A1

Abstract

The invention discloses a heart valve stent and a prosthesis thereof, which comprise a stent main body, wherein the stent main body consists of mutually connected grid structure units, the stent main body is axially divided into an inflow channel, a transition section and an outflow channel which are sequentially connected, and the stent also comprises a limiting structure connected with the stent main body; the limiting structures are distributed on the outflow channel or the transition section along the circumferential direction, and the limiting structures are provided with first protrusions used for limiting the support to move from the inflow channel to the outflow channel. According to the invention, the limiting structure is arranged on the outflow tract of the stent, so that the stent can be prevented from moving towards the outflow tract under the scouring of blood flow. The inflow channel of the support is set to be in a shape suitable for the native tissue, and the outer skirt edge is arranged on the outer side circumference of the inflow channel at the joint part of the inflow channel and the native tissue, so that the perivalvular leakage can be effectively prevented, and the valve is prevented from moving towards the direction of the inflow channel. In addition, the size of the inflow channel of the stent can be shorter, the atrioventricular conduction block is effectively prevented, and the size of the outflow channel can also be shorter, so that the compression on the aorta is reduced.

Description

Heart valve support and prosthesis thereof

Technical Field

The invention relates to an interventional medical prosthesis, in particular to a heart valve stent and a prosthesis thereof.

Background

With the advent of the global aging society, aortic valvular disease has become one of the common cardiovascular diseases. The incidence rate in China is 2% -5%, and the incidence rate is third after coronary heart disease and hypertension in Europe and America. Thousands of patients can benefit from surgical aortic valve replacement every year, but even in developed countries, a large number of patients with serious aortic valve diseases cannot receive surgical treatment due to late disease, advanced age, various complications and the like, and the appearance of percutaneous artificial aortic valve products and the continuous improvement of the product performance undoubtedly bring good news to the part of patients and provide an effective treatment method.

In 2002, Cribiier et al first reported a first case of transcatheter aortic valve replacement in humans, and thereafter, many scholars and doctors at home and abroad developed basic and clinical studies on Transcatheter Aortic Valve Replacement (TAVR) and achieved better clinical effects, and the studies showed that: the new technique is safe and effective for patients who can not perform surgical valve replacement or have high risk of surgical valve replacement. Compared with the surgical operation, the percutaneous aortic valve replacement does not need thoracotomy and extracorporeal circulation support, and is a treatment method which has the advantages of small wound, less complication, quick postoperative rehabilitation, less pain of patients and easy acceptance. Although most of patients who are subjected to TAVR surgery are high-risk patients, the survival rate of the patients after surgery is higher than 90 percent in 30 days, and the hemodynamics index of the patients after surgery is obviously improved.

The release of the existing TAVI valve prosthesis is mostly by means of self-expansion or balloon expansion. The principle is that the stent is compressed in a sheath tube, is conveyed to the aortic valve through the femoral artery or the apex of the heart by a conveyor and is released at the calcified valve ring, the expanded stent immediately props up the calcified valve ring, the whole artificial valve prosthesis is fixed, and the valve leaf starts to work after being opened.

In view of clinical manifestations, home and abroad aortic stents face a plurality of problems to be solved urgently.

1. After the stent is released in vivo, the stent is easy to displace;

2. the valve prosthesis has limited perivalvular leakage prevention capability;

3. an excessively long inflow channel of a heart valve prosthesis easily causes atrioventricular block.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a heart valve stent and a prosthesis thereof, which can prevent the risk that the stent moves from an inflow channel to an outflow channel under the scouring of blood flow, and have simple structure and easy implementation.

The technical scheme adopted by the invention for solving the technical problems is to provide a heart valve stent, which comprises a stent main body, wherein the stent main body consists of mutually connected grid structure units, the stent main body is axially divided into an inflow channel, a transition section and an outflow channel which are sequentially connected, and the stent is also provided with a limiting structure connected with the stent main body; the limiting structures are distributed on the outflow tract or the transition section along the circumferential direction, and the limiting structures are provided with first protrusions used for limiting the support from moving from the inflow tract to the outflow tract.

Furthermore, the limiting structure and the bracket main body are manufactured separately and then assembled.

Further, the first protruding part is an arc-shaped protrusion, a trapezoid protrusion, a wave-shaped protrusion or a sawtooth protrusion.

Further, the area of the grid structure unit of the bracket at the transition section is larger than that of the inflow channel or the outflow channel.

Further, the transition section has a concave structure away from the first protrusion.

Further, the distance between the plane where the vertex of the first convex part is located and the plane where the outflow tract port is located is 0-30 mm.

Further, the port of the outflow tract does not protrude out of the sinotubular junction after the stent is released for stenting.

Further, the inflow channel presents at least one contact location with native tissue above the annulus after the stent is released from the stent.

Further, after the stent is released and expanded, the inflow channel is tightly attached to native tissue below the valve annulus.

Furthermore, the value range of the distance d from the plane of the tail end of the inflow channel of the bracket to the plane of the valve ring is more than 0 and less than or equal to 15 mm.

The present invention provides a heart valve prosthesis, including a stent and a leaflet, wherein the stent is the stent, and the leaflet is fixed on the inner side of the stent.

Further, the heart valve prosthesis also comprises an inner skirt edge which is arranged on the inner side of the support.

Further, the stent is released from the stent and the inflow channel has at least one contact location with native tissue above the annulus, and the stent is provided with an outer skirt at the contact location of the inflow channel and native tissue.

Further, after the support is released and expanded, the inflow channel is tightly attached to the native tissue below the valve ring, and an outer skirt edge is arranged at the attachment position of the inflow channel and the native tissue.

Compared with the prior art, the invention has the following beneficial effects: according to the heart valve stent and the prosthesis thereof provided by the invention, the limiting structure is arranged at the position of the outflow tract or the transition section of the stent, so that the risk that the stent moves from the inflow tract to the outflow tract direction under the scouring of blood flow can be prevented. The inflow channel of the support is set to be in a shape matched with the native tissue, and meanwhile, the outer skirt edge is arranged on the outer circumferential direction of the inflow channel at the joint part of the inflow channel and the native tissue, so that the valve periphery leakage can be effectively prevented. In addition, because the first bulge is arranged, the inflow channel is arranged to be matched with the shape of the native tissue to fix the support, the size of the extension of the inflow channel of the support towards the valve ring direction can be set to be shorter, and atrioventricular block can be effectively prevented.

Drawings

FIG. 1 is a schematic structural view of a heart valve stent according to an embodiment of the present invention;

FIG. 2a is a schematic view of a retention structure on the stent outflow tract of a heart valve prosthesis according to an embodiment of the present invention;

2 b-2 e are schematic structural views of first protrusions on a limiting structure on a stent outflow tract of a heart valve prosthesis according to an embodiment of the invention;

FIG. 3 is a schematic view of a concave structure on a stent transition section of a heart valve prosthesis according to an embodiment of the invention;

fig. 4a and 4b are schematic structural diagrams of an inflow passage of a heart valve prosthesis according to an embodiment of the invention.

In the figure:

10 support 20 annulus 30 coronary sinus ostium

101 inflow 102 transition 103 outflow

104 contact position 1021 concave structure 1022 second convex part

1031 limiting structure 1032 first bulge 40 sinotubular junction

Detailed Description

The invention is further described below with reference to the figures and examples.

Fig. 1 is a schematic structural diagram of a heart valve stent in an embodiment of the invention.

The heart valve prosthesis provided by the invention comprises a support 10, valve leaflets and a skirt (not shown in the figure), and referring to fig. 1, the support 10 comprises a support main body and a limiting structure 1031 connected with the support main body. The stent main body consists of grid structure units which are connected with each other, and the stent main body is axially divided into an inflow channel 101, a transition section 102 and an outflow channel 103; depending on the direction of blood flow, the transition section 102 is located downstream of the inflow channel 101 and the outflow channel 103 is located downstream of the transition section 102. Inflow channel 101 corresponds to the portion of blood flowing into the prosthesis during valve operation, and outflow channel 103 corresponds to the portion of blood flowing out of the prosthesis during valve operation. After the stent 10 is released and expanded, the inflow channel 101 is matched with the shape of the native tissue, a limiting structure 1031 is arranged on the outflow channel 103 or the transition section 102 along the circumferential direction of the stent 10, the limiting structure 1031 is provided with a first convex part 1032 for limiting the stent 10 to move from the inflow channel 101 to the outflow channel 103, preferably, the limiting structure 1031 is arranged on the outflow channel 103, and the vertical distance between the plane of the vertex of the first convex part 1032 and the plane of the port of the outflow channel 103 is 0-30 mm; in another embodiment, the limiting structure 1031 is arranged on the transition section 102, preferably, the limiting structure 1031 is arranged on the transition section 102 near the outflow tract 103. Preferably, after the stent 10 is released from the stent, the port of the outflow tract 103 does not extend beyond the sinotubular junction 40, i.e., the port of the outflow tract 103 is in a plane that is flush with or below the plane of the sinotubular junction 40, and the sinotubular junction 40 is the junction of the aortic sinus and the aorta. The limiting structures 1031 may be partially distributed in the circumferential direction, may be completely distributed in the circumferential direction, and preferably are completely distributed in the circumferential direction.

In the heart valve prosthesis provided by the invention, the stent 10 is made of a metal material, and is preferably prepared by cutting a nickel-titanium tube. The valve leaf and the skirt are made of animal-derived materials, such as animal pericardium, or biocompatible high polymer materials, such as polyurethane.

Fig. 2a is a schematic view of a position-limiting structure on a stent outflow tract of a heart valve prosthesis according to an embodiment of the present invention.

Referring to fig. 1 and 2a, the limiting structure 1031 has a first protrusion 1032, and the first protrusion 1032 has elasticity and can be compressed in the radial and axial directions. The first boss 1032 may be made of the same material as the holder main body, or may be made of another material or structure having elasticity. The first boss 1032 can be integrally manufactured with the bracket main body, or can be assembled and connected after being manufactured in a split mode, wherein the integral manufacturing means that the bracket main body is cut from a metal pipe and then is shaped through heat treatment; or braided from one or more wires. The separate manufacturing means that the components are separately manufactured and then assembled and connected by welding or the like. The first protrusion 1032 may be an arc protrusion, a trapezoid protrusion, a wave protrusion, a zigzag protrusion, or the like, as shown in fig. 2b to 2 e. The first protrusion 1032 has at least one protrusion which is located on a region between the sinotubular junction 40 and the coronary ostium 30, and is in contact with or not in contact with tissue located between the sinotubular junction 40 and the coronary ostium 30 when the stent 10 is released and fixed at a specific location of the heart, and the first protrusion 1032 functions to restrict the stent 10 from moving in a blood flow direction from the inflow tract toward the outflow tract. When the stent 10 is subjected to an external force in the direction of blood flow, such as blood flow scouring, the stent 10 will tend to displace in the direction of the sinotubular junction 40, and at least one contact point between the first projections 1032 and the native tissue will limit the stent 10 from moving further upward.

The stent 10 of the present invention has a lattice cell structure, generally diamond-shaped, but may be any other suitable shape, such as pentagonal, hexagonal, etc., that forms a closed shaped cell. In order to avoid the coronary sinus ostium 30 from being blocked, the transition section 102 may be designed to have a larger size lattice structure, for example, the lattice structure cell area is larger than the cross-sectional area of the coronary sinus ostium 30, or the lattice structure cell area of the transition section 102 is larger than the lattice structure cell area of the inflow tract 101 or outflow tract 103. It is also possible to have a concave structure 1021 in the transition section 102 away from the first boss 1032, and in particular, the transition section 102 has a concave structure 1021 at the location of the coronary ostium 30. The concave structure 1021 is concave towards the direction away from the coronary ostium 30, and has a certain distance with the coronary ostium 30, and the two ends of the concave structure 1021 are provided with second convex portions 1022, as shown in fig. 3, the concave structure 1021 can also prevent the coronary ostium 30 from being blocked.

The shape of the inflow channel 101 of the stent 10 of the present invention is configured to conform to the shape of the native tissue to prevent paravalvular leakage. In order to more clearly describe the structural features of the present invention, the present invention adopts "upper" and "lower" as the directional words, the inflow channel 101 is located "lower", and the outflow channel 103 is located "upper". As shown in fig. 4a, there may be at least one contact site 104 with native tissue above the annulus 20, and a close fit with native tissue below the annulus 20, the contact site 104 above the annulus 20 with native tissue may further prevent paravalvular leakage. Alternatively, as shown in fig. 4b, the inflow channel 101 may be in close proximity to the annulus 20 and in close proximity to the native tissue.

In order to further prevent the paravalvular leakage, the inflow channel 101 of the stent 10 is sewn with a skirt, and the skirt can be single-layer or double-layer. The double-layer skirt means that the skirt is sewn on both the inner layer and the outer layer of the inflow channel 101, the inner skirt is sewn on the inner layer of the inflow channel 101, and the outer skirt is sewn on the outer layer of the inflow channel 101. The single-layer skirt means that an inner skirt is sewn to the inner layer of the inflow channel 101. The inner skirt is fixed to the inside of the inflow channel 101 and is fixedly connected to the valve leaflet. Preferably, the inner layer of the inflow channel 101 is sewn with an inner skirt, the outer skirt is sewn at the contact position 104, and the outer skirt is sewn at the joint position of the inflow channel 101 and the native tissue, so that the perivalvular leakage can be effectively prevented.

Since the stent 10 has been fixed by providing the first protrusion 1032 in the area of the outflow channel 103 and by adapting the inflow channel 101 to the native tissue shape, the dimension of the inflow channel 101 of the stent 10 extending beyond the valve annulus 20 can be set short, for example, the vertical distance d from the plane of the valve annulus 20 to the plane of the distal end of the inflow channel 101 of the stent is 0 < d ≦ 15 mm. Compared with the traditional stent, the stent has the advantages that d is smaller, and atrioventricular block can be effectively prevented; the conventional stent is long in this portion because paravalvular leakage is prevented, and the stent is set to be too short to easily move from the inflow channel toward the outflow channel.

In summary, the outflow tract 103 of the heart valve prosthesis and the stent 10 according to the present invention is provided with the position-limiting structure 1031 near the transition section 102, so that the risk that the stent 10 moves from the inflow tract to the outflow tract under the scouring of blood flow can be prevented. The inflow channel 101 of the stent 10 is configured to match the native tissue, and the outer skirt is provided on the outer circumference of the inflow channel 101 at the position where the inflow channel is attached to the native tissue, so that the paravalvular leakage can be effectively prevented. In addition, because the first convex part 1032 is arranged and the inflow channel 101 is arranged to be adapted to the shape of the native tissue to realize the fixation of the stent 10, the size of the inflow channel 101 of the stent 10 extending towards the valve annulus 20 can be set to be short, and atrioventricular block, embolism and the like can be effectively prevented. Meanwhile, the port of the outflow tract 103 may not extend out of the sinotubular junction 40, and the outflow tract may be set to be shorter in size, thereby reducing the pressure on the aorta.

Although the present invention has been described with respect to the preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A heart valve stent comprises a stent main body, wherein the stent main body is composed of grid structure units which are connected with each other, and the stent main body is axially divided into an inflow channel, a transition section and an outflow channel which are sequentially connected with each other; the limiting structures are distributed on the outflow tract or the transition section along the circumferential direction, and the limiting structures are provided with first protrusions used for limiting the support from moving from the inflow tract to the outflow tract.

2. The heart valve stent of claim 1, wherein the retention structure is fabricated separately from the stent body and then assembled.

3. The heart valve stent of claim 1, wherein the first projections are arcuate projections, trapezoidal projections, wavy projections, or saw-tooth projections.

4. The heart valve stent of claim 1, wherein the area of the lattice structure cells at the transition section on the stent is greater than the area of the lattice structure cells of the inflow tract or outflow tract.

5. The heart valve stent of claim 1, wherein the transition section has a concave configuration distal to the first protrusion.

6. The heart valve stent of claim 1, wherein a distance between a plane of the apex of the first boss and a plane of the outflow tract port is 0-30 mm.

7. The heart valve stent of claim 6, wherein the port of the outflow tract does not protrude beyond the sinotubular junction after the stent is released from the stent.

8. The heart valve stent of claim 1, wherein the inflow tract presents at least one contact location with native tissue above the annulus after the stent is released from stenting.

9. The heart valve stent of claim 1 or 8, wherein the inflow tract is in close proximity to native tissue below the annulus after the stent is released from stenting.

10. The heart valve stent of claim 1, wherein the distance d from the plane of the inflow channel end of the stent to the plane of the valve annulus is in the range of 0 < d ≦ 15 mm.

11. A heart valve prosthesis comprising a stent and leaflets, wherein the stent is a stent according to any one of claims 1 to 10, and the leaflets are fixed to the inside of the stent.

12. The heart valve prosthesis of claim 11, further comprising an inner skirt disposed inside the stent.

13. The heart valve prosthesis of claim 12, wherein the inflow channel has at least one contact location with native tissue above the annulus after the stent is released from the stent, and wherein the stent is provided with an outer skirt at the contact location of the inflow channel and native tissue.

14. The heart valve prosthesis of claim 11 or 13, wherein the inflow tract is in close apposition to native tissue below the annulus after the stent is released from the stent, the stent being provided with an outer skirt at the apposition of the inflow tract and native tissue.