CN116138928A - Interventional mitral valve capable of reducing left ventricular outflow port - Google Patents

Abstract

The invention relates to an interventional mitral valve comprising a frame, leaflets and a sealing group, the valve having three leaflets, characterized in that the frame is composed of a ventricular part and an atrial part, wherein the ventricular part has an opening on one side of the anterior leaflet of the natural valve, allowing the anterior leaflet to at least partially return to its natural position when the ventricle contracts. The valve is used for reducing the blocking of the left ventricular outflow port after valve implantation while maintaining the valve positioning, further improving the clinical effect of the intervention mitral valve and expanding the application range of the intervention mitral valve.

Description

Interventional mitral valve capable of reducing left ventricular outflow port

Technical Field

The invention belongs to the technical field of medical appliances, and particularly relates to an interventional mitral valve.

Background

Valve disease is a common heart valve disease with a gradually increasing incidence with age. For diseased valves, surgical operations are generally used for prosthetic heart valves, but some patients cannot accept surgical operations due to age and the like, and for such patients, interventional valves can be used, so that the surgical heart valves do not need to open the chest, have the advantages of small wounds, quick recovery and the like, and are receiving more and more attention.

Interventional aortic valves have evolved over the last two decades with good progress and are now becoming the standard treatment for non-surgically or surgically high risk patients. However, because of the complex anatomy of the mitral valve, many complications occur after the intervention mitral valve is implanted in the body, which makes the intervention mitral valve relatively slow to develop.

The native mitral valve differs from the aortic valve by having three leaflets, which have only two leaflets: anterior and posterior lobes. When the ventricle contracts, the two valve leaflets close together, so that blood in the ventricle enters the aorta in one way. When the pathological changes occur, mitral valve leaflets cannot be effectively involuted, so that backflow in the atrial direction is generated when the ventricles contract, and the blood supply efficiency is affected. In addition, when the valve leaflet is closed, the front leaf is far away from the ventricular outflow port, so that the front leaf can not block the ventricular outflow port when the ventricle contracts. After the intervention mitral valve is implanted, the anterior leaflet can be supported by the valve frame of the valve, so that the anterior leaflet can not shrink along with ventricular contraction, the left ventricular outflow port is blocked by the valve frame, and the effect of the intervention mitral valve after implantation is affected.

Meanwhile, the aortic valve is mainly stenosed caused by calcification of the valve, the main lesion of the mitral valve is valve regurgitation, calcified plaque of the structure of the regurgitation mitral valve is less, the implanted interventional mitral valve is difficult to position, and the valve is easy to slide after implantation. In addition, the natural mitral valve annulus structure presents a three-dimensional saddle shape in three dimensions, and its projection on a plane presents a D-shaped non-circular shape. The current conventional round design causes the deformation of the valve frame to seriously affect the function of the valve leaflet of the interventional mitral valve after the valve is implanted. Finally, tendon structures are attached to the lower surfaces of the natural mitral valve leaflets, and the existence of the tendon structures further interferes with the implantation of the intervention mitral valve.

Many designs and inventions have been developed to solve the above-mentioned problems of the interventional mitral valve, but there are always some problems at present due to the specific manner of the structure adopted, especially in the blocking of the left ventricular outflow port, and although the new design can effectively reduce the blocking effect, the effect is limited due to the limited implementation form of the specific structure of the interventional valve, and the clinical use effect and the clinical use range are limited on the premise of keeping the effective positioning and working of the interventional mitral valve. Therefore, the structural design of the novel valve holder is very important.

Disclosure of Invention

The present invention provides an interventional mitral valve, the valve holder being comprised of a ventricular portion and an atrial portion. Wherein the ventricular part valve frame and the corresponding part of the anterior leaflet of the self-valve are provided with partial valve frame supporting structures or are not provided with valve frame supporting structures, so that the anterior leaflet of the natural valve can maintain partial or complete natural functions after the interventional mitral valve is implanted in a body. For the condition of only having a part of the support structure of the valve frame, the natural anterior leaflet of the mitral valve can be in a partial closing state when the ventricle contracts, and the partial closing can effectively reduce the blocking of the left ventricular outflow port. For the situation that the supporting structure is not arranged on the corresponding part of the anterior leaflet, the anterior leaflet can realize the maximum closing when the ventricle contracts, the closing amplitude depends on the structural design of the intervention mitral valve frame and the leaflet, and under ideal conditions, the closing of the leaflet corresponding to the intervention mitral valve and the natural valve anterior leaflet can be realized. The implementation of the invention can further improve the clinical effect of the intervention mitral valve and expand the application range thereof.

For a surgically replaced mitral valve, because the leaflets of the native mitral valve are removed, while the surgically implanted prosthetic mitral valve has one leaflet that substantially corresponds to the anterior leaflet of the native valve, there is no other blocking structure in the corresponding position, so that when the ventricle contracts, the valve She Hui closes, thus reducing or eliminating the obstruction of the left ventricular outflow orifice. The key of the invention is to endow the surgical mitral valve with the feature of a prosthetic mitral valve.

In view of the posterior leaflet of a native mitral valve, there are generally no problems associated with the posterior leaflet portion of the valve frame, and thus the corresponding posterior leaflet portion of the valve frame can be designed with reference to conventional designs so that the frame can prop up the posterior leaflet of the native mitral valve from functioning. In addition, designs similar to the anterior leaflet position of the valve frame are also contemplated, but are not preferred.

Further, to maximize the reduction of anterior leaflet obstruction to the left ventricular outflow orifice, the valve recommends a conventional three leaflet structure, with the leaflets meeting one another. The two supporting structures which are connected with the two corresponding valve leaflets of the valve frame are respectively positioned near the fiber triangle of the front valve leaflet of the natural valve when being implanted, and one supporting structure is positioned at the central part of the rear valve leaflet of the natural valve. The supporting structure is positioned at the anterior leaflet fiber triangle, so that the influence of the leaflet supporting structure on the anterior leaflet motion of the natural mitral valve can be reduced to the greatest extent. While maximizing the surgical effect of the simulated surgical flap.

In practice, the ventricular part of the valve holder of the present invention may be provided with a fixing element for fixing the valve to the implantation site, and the fixing element may be one or a combination of more than one of barbs, barbs and traction. The barb structure can partially clamp the front leaf or the rear leaf of the natural valve, so that the natural valve leaf is positioned between the valve frame and the barb, and the valve is prevented from moving to an atrium when the ventricle contracts. The barbs are preferably arranged at the front leaf position and the rear leaf position of the natural valve respectively, the fiber triangular positions at the two sides of the front leaf are preferably arranged at one, and the scheme is that the barbs are arranged at the rear leaf position. The specific position of the valve is preferentially consistent with the valve leaflet involution fixed supporting position so as to maximally reduce the blocking of the natural valve leaflet movement. The barbs are arranged on the valve frame, and a plurality of thorns facing to the atrial surface are arranged on the valve frame, so that the barbs penetrate through natural valve leaflets, and the purpose of moving the valve to the atrium when the tissue ventricle contracts is achieved. The traction structure is a traction rope arranged on the valve frame, the other end of the traction rope is fixed on cardiac muscle of the ventricle, and when the ventricle contracts, the blood bears the rope which is used for traction on the impact force of the implanted intervention mitral valve to the atrial direction, so as to prevent the valve from moving to the ventricular direction. The end of the pull cord in contact with the valve frame is preferentially disposed on the support structure of the valve leaflet.

The fixing piece and the valve frame are integrally designed, and the fixing piece is directly used as a part of the valve frame structure, for example, the fixing piece is integrally cut on a pipe material and then qualitatively obtained by means of heat treatment; or qualitatively obtained after integral braiding. In addition, the fixing piece can also be of an independent structure, and is obtained by being connected with other parts of the valve frame after being processed. For example, the main body is processed by adopting a pipe cutting mode, and the fixing piece is formed by connecting the main body structure through a connecting mode such as welding, riveting or sewing after weaving or independent cutting.

In the implementation process, the valve holder disclosed by the invention can be provided with corresponding atrial surface fixing parts at the atrial part, and the fixing parts are one or more of a planar flange structure, a conical surface structure and a circular structure. The atrial surface is arranged to prevent the valve from sliding in the ventricular direction during ventricular diastole. The ventricular surface can be matched with the mitral valve annulus by adopting a planar flange structure, can also be matched with the mitral valve annulus and part of the atrial wall by adopting a conical surface structure, or can be matched with the integral structure of the atrium by adopting a circular or special-shaped structure. Once the valve is matched with the integral structure of the atrium, the valve can slide towards the ventricular direction, and the atrium can bear the impact force of the valve towards the atrial direction when the ventricle contracts, and the ventricular surface is fixed.

The valve frame disclosed by the invention can be provided with the fixing layer between the atrial part and the ventricular part, and is used for specially fixing the valve to the implantation position, the diameter of the fixing layer is generally smaller than that of the ventricular part and the atrial part, so that the valve frame integrally forms a girdle structure, the fixing layer is matched with an annulus of a natural valve, and the corresponding atrial part and ventricular part are correspondingly arranged on corresponding atrial surface and ventricular surface, so that the valve is fixed at the implantation position. The corset is formed to effectively prevent movement of the valve into the atrium when the ventricle contracts, and also to allow movement of the valve into the ventricle when the heart is diastole.

The valve frame can be provided with a flexible contact surface or a rigid isolation structure for reducing damage when the natural valve leaflet is closed and/or interference with the valve leaflet of the intervention mitral valve. To prevent or reduce damage to the native mitral valve leaflets during ventricular systole due to repeated contact with the valve frame.

Wherein the flexible contact surface is any material that can meet this purpose, such as biological material, e.g. porcine pericardium, bovine pericardium material; or polymer materials such as silica gel, implantable fabrics, and soft swelling materials such as swelling polytetrafluoroethylene; combinations of corresponding materials are also possible, such as a fabric wrapped with a silicone pericardial material, wrapped with silicone.

In addition, the rigid isolation structure is a structure for isolating the natural valve leaflet from being contacted with the valve leaflet of the intervention mitral valve in a closed state, for example, the rigid structure can be adopted to rigidly isolate the corresponding parts of the natural valve leaflet and the implanted valve, so that the natural valve leaflet cannot generate impact movement with valve components in the movement process.

Finally, considering that the natural mitral valve annulus is of a non-circular structure, in order to reduce side effects caused by deformation of the valve frame after the circular structure is implanted, the valve frame structure of the mitral valve is preferably designed in a D-type structure, but is limited to be designed in a conventional circular design structure. The valve provided by the invention can be used for tricuspid valve after being regulated to a certain extent, and can be used for reducing the blocking of the right ventricular outflow opening when the tricuspid valve leaves shrink in the ventricle under the premise of ensuring the positioning and the functions.

Drawings

FIG. 1 is a schematic illustration of a natural mitral valve in its normal state with a contracted ventricle;

FIG. 2 is a schematic illustration of a natural mitral valve undergoing regurgitation with ventricular contractions;

FIG. 3 is a schematic view of a projection of the mitral valve as seen in an atrial direction;

fig. 4 a) to 4 c) are schematic views of different angles of an interventional mitral valve according to an embodiment of the present invention;

fig. 5 a) and 5 b) are schematic views of the position of an interventional mitral valve (without the subvalvular structure) when placed in the body;

FIGS. 6 a) and 6 b) are schematic views of the position of an interventional mitral valve (containing an subvalvular structure) as it is placed into the body;

FIG. 7 is a schematic illustration of the structure of an interventional mitral valve in accordance with another embodiment of the present invention;

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings and embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

As shown in fig. 1, heart 10 includes a left atrium 101, a left ventricle 102, mitral valve leaflets 103, chordae tendineae 104, papillary muscles 105, and the like. When the natural mitral valve is not diseased, and in a normal state, the heart chamber 102 contracts, the mitral valve leaflets 103 coapt, and blood can only flow out of the aorta 106 in the direction of the arrows as shown. The mitral valve leaflet closes while the anterior leaflet 1031 is away from the aortic orifice so that the leaflet does not block the left ventricular outflow orifice. When a lesion occurs, the ventricle 102 contracts, the anterior and posterior leaflets of the mitral valve still show coaptation, but the coaptation at this time cannot completely close the two leaflets, as shown in fig. 2, so that when blood flows out from the aorta 106, a part of the blood flows into the left atrium 101 from the gap where the blood is not completely closed, and the blood supply of the human body is insufficient, but when the blood is not completely closed, a corresponding complication occurs.

Fig. 3 a) and b) show the situation when the natural valve is completely involuted without lesions and when the lesions are not completely involuted, respectively, when seen from the atrial direction. Fig. 3 a) is a normal valve with the anterior leaflet 1031 and the posterior leaflet 1032 attached to the annulus and the ventricle normally closed when contracted. Fig. 3 b) shows the valve in a diseased state, with gaps after anterior and posterior closure when the ventricle contracts. It can also be seen that the natural annulus assumes a D-shaped configuration, rather than a circular configuration resembling an aortic valve, with the non-circular portion being located at the junction of the anterior leaflet 1031 and the junction of the posterior leaflet 1032 remaining substantially circular, thereby assuming a D-shaped configuration as a whole. In addition, the fiber triangles are located in the area adjacent to the anterior leaflet 1031 and the posterior leaflet 1032, the natural valve annulus between the fiber triangles is relatively stiff, and is relatively less contracted during diastole and relatively larger elsewhere.

Fig. 4 is a schematic structural view of an interventional mitral valve according to an embodiment of the present invention. In this embodiment, the valve is composed of a valve frame 20, a valve leaflet and a sealing skirt, wherein the sealing skirt is wrapped on the valve frame to prevent paravalvular leakage after the valve is implanted, the valve leaflet is fixed on the valve frame and the sealing skirt through a suture, and the valve leaflet and the sealing skirt are not shown in the figure and can be obtained by referring to the related art. The valve frame structure is composed of a ventricular part 202 and an atrial part 201. The atrium 201 is in a flange-shaped structure, which is adapted to the annular structure, and has a diameter larger than that of the natural valve annulus, so that the valve can be prevented from sliding into the ventricle from the atrium during diastole. The flange structure referred to herein means that the diameter of the atrial portion is larger than the diameter of the ventricular portion, in other words, the atrial portion expands radially outwardly relative to the ventricular portion. In this embodiment, the ventricular section 202 is formed with three struts 2021 which are preferably uniformly distributed over the circumferential surface of the ventricular section. Each strut is used for connecting two adjacent valve leaflets and is an involutory supporting part of the adjacent valve leaflets. By adjusting the support structure 2022 of the ventricular part other than the struts 2021, the range of motion of the mitral valve leaflet 103 can be varied, and preserving full or partial natural motion of the mitral valve leaflet 103 can be achieved.

Fig. 5 and 6 show schematic views of an interventional mitral valve when implanted in a body, and fig. 5 and 6 also show comparative schematic views of a conventional interventional mitral valve and an interventional mitral valve of the present invention, respectively, after implantation. In which fig. 5, in order to more clearly show the movement of the natural leaflet, the inferior structural chordae tendineae, papillary muscles, etc. of the leaflet are removed so as to more clearly show the corresponding mechanism of action. As can be seen in fig. 5 a) and 6 a), after implantation of the conventional interventional mitral valve 20, the natural leaflets 103 are both spread apart tightly around the periphery of the valve 20. When the ventricle contracts, the natural leaflet 103 can not be closed any more, and is completely disabled, and its function is replaced by the artificial leaflet of the interventional mitral valve. But the natural anterior leaflet and the valve frame can not be closed, so that the left ventricular outflow port is blocked, the passage area of blood flow is reduced, and corresponding resistance is generated. In severe cases, blood flow may even be completely blocked from entering the aortic valve, making blood supply inefficient. While the interventional mitral valve 20 of the present invention is implanted with the two support posts 202 of the control valve symmetrically positioned about two fiber triangles and the other is positioned about the center of the posterior leaflet 1032 of the native valve. In this structure, the anterior leaflet 1031 of the natural valve does not have the blocking of the valve structure, so that when the ventricle 102 contracts, the anterior leaflet 1301 of the natural valve can realize all or part of the movement, and the blocking of the outflow opening of the left ventricle 102 is reduced, as shown in fig. 5 b) and 6 b).

As shown in fig. 4 a), b) and c), the struts are preferably not uniformly sized from top to bottom, but have an inverted triangular shape, which is advantageous in that the illustrated struts provide sufficient support strength relative to the rod-shaped struts, while limiting the extent to which the anterior leaflet 1031 of the heart closes, and reducing interference with the operation of the leaflets of the interventional valve.

As a variant, the ventricular part may be of a structure without three struts, but only with an opening on the side of the ventricular part facing the anterior leaflet of the natural valve, allowing said anterior leaflet to return at least partially to its natural position when the ventricle contracts, the remainder of the ventricular part being of a circumferential structure or of a strut structure, the struts being open outside.

In addition, the present invention may simultaneously couple one rope 203 to each of the vertices of the three struts 2021. The other end of this cord 203 is then secured to the ventricular wall, preferably at the apex of the ventricular wall. The three cords pull effectively prevents the valve from sliding into the atrium due to the force of the ventricular blood impact when the ventricle contracts, further increasing the positioning ability of the valve in the body, as shown in fig. 7.

In addition, corresponding developing points can be selectively arranged on two support columns 202 adjacent to the fiber triangle, so that a doctor can conveniently identify corresponding positions during implantation, and implantation is effectively realized. At the same time, at a position outside the two fiber triangle areas corresponding to the front lobe 1031, a supporting structure can be added, so that the natural rear lobe 1032 is unfolded and does not work any more, and possible interference of the natural rear lobe is reduced.

In this embodiment, the valve may be provided with barbs on the sides of the three struts 2021. When the valve is implanted, the leaflets 103 of the native valve are trapped between the barbs and the ventricular portion of the interventional valve 20, that is, the barbs catch on the leaflets 103 of the native valve, by control of the release process. In this way, the impact of ventricular blood on the interventional valve during ventricular systole can be effectively prevented from causing the interventional valve to slide into the atrium, and the barb structures can be arranged as described in US10537422B2 or US9744036B 2. But differs in that the barbs in the reference are all located at non-strut locations, whereas the barbs of the present invention are located at strut locations, which both function to prevent the valve 20 from sliding into the heart chamber 102 as described in the reference, and effectively reduce the obstruction of the left ventricular outflow port by the native leaflet anterior leaflet 1031. The barb and the intervention valve main body are preferably arranged into a split structure, the barb and the intervention valve main body are independently processed, and then the barb is sewn on the support 2021, and can be connected in a welding, riveting and other modes. Preferably woven from wire, or cut or machined in any other feasible manner, such as sheet or tube.

In addition, to prevent the valve 20 from sliding from the atrium 101 into the ventricle 102 during diastole, the three struts 202 may have corresponding barb structures on their sides, which, when the valve 20 is implanted, penetrate the leaflets 103 of the native valve by control of the release process. The barb and the valve main body are of an integrated structure, the barb and the valve main body are integrally cut through a pipe, and then are shaped through a shaping process, and the barb structure can be arranged in a split-type shaping mode and then connected with a specific barb structure, and can be obtained according to the CN109106470A and other documents.

Preferably, a waist-shaped structure with a thick upper part and a thin middle part is formed between the atrium part 201 and the ventricle part 202, and is clamped at the annulus of the natural mitral valve, and the larger ventricle part and the larger atrium part are used for preventing the valve from sliding in the positioning position. The ventricular section also retains three struts 2021, each for connecting adjacent leaflets. There is no other support structure beyond the struts. The corset structure is described in US10368990B2, etc. Other structural arrangements for preventing slippage to the atrium 101 may be referred to in the relevant literature and will not be described again.

In addition, in order to ensure the effect of valve implantation, the support column 202 of the valve frame in the present invention is preferably arranged in a conical structure inclined to the center of the valve, or in any structure gathered to the center, such as a circular arc structure. The structure can ensure the closing of the anterior leaflet of the natural valve when the ventricle contracts, and can partially reduce the blocking of the left ventricle outflow opening after the intervention mitral valve is implanted.

The natural valve annulus generally assumes a D-shape, as shown in fig. 3, so that the valve frame structure of the valve may be configured as a D-shape to better conform to the shape of the natural valve annulus. The D shape can effectively reduce the influence of deformation of the valve frame on valve leaflet involution after valve implantation and reduce the central reflux of the implanted valve. Meanwhile, the D-shaped structure can reduce the support to the anterior annulus of the valve annulus, reduce the influence on the anterior leaflet of the aorta and the mitral valve, and greatly reduce the blocking to the outflow port of the left ventricle.

In addition, at present, the valve is designed to be generally coated with only one layer of polymer fabric outside the valve frame so as to reduce the peripheral leakage of the valve, but the overall rigidity is high, the natural valve leaves repeatedly move to be contacted with the valve frame to easily cause the valve She Sunshang, the outer layers of the three support posts and the valve frame part contacted with the valve leaves are preferably considered to be provided with one layer of flexible damage prevention structure for reducing the damage speed, and the flexible damage structure is divided into three layers. Wherein the innermost layer is a valve frame body, the valve frame is tightly adhered with silica gel, and the outer layer is made of fabric material. Wherein the silica gel material is used for providing buffering when contacting with the valve, and the silica gel material with lower hardness and better elasticity is recommended. Other soft and elastic materials may be used instead, such as gels, foams, fabrics, etc. The outer layer is made of fabric material and is used for promoting the growth of endothelial cells and accelerating the endothelialization of the implant.

The silica gel material and other flexible materials can be connected with the support column by adopting modes of integral cladding, integral injection molding, compression molding, dipping and the like. Or may be a preformed material which is then directly wrapped with fabric material after contact with the support posts. The fabric can be a commonly used medical implant fabric material, such as polyester fiber cloth, polytetrafluoroethylene fabric and the like.

Considering that the tricuspid valve has a similar structure to the mitral valve, the valve according to the invention can be applied to the tricuspid valve directly or after a certain modification while retaining the technical features of the invention.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.

Claims (10)

1. An interventional mitral valve comprising a frame, leaflets and a sealing population, the valve having three leaflets, characterized in that the frame is composed of a ventricular part and an atrial part, wherein the ventricular part has an opening on the anterior leaflet side of the natural valve, allowing the anterior leaflet to at least partially return to its natural position when the ventricle contracts.

2. The interventional mitral valve of claim 1, wherein the ventricular portion is formed of 3 struts, each strut connecting two adjacent leaflets, the struts being apposed support sites for the adjacent leaflets, the portions between the struts being substantially open, two of the struts after implantation being located respectively adjacent to the anterior leaflet fiber triangle of the native valve and the other being located at the central portion of the posterior leaflet of the native valve.

3. The interventional mitral valve of claim 1, wherein the ventricular portion of the valve frame has a fixation element that secures the valve to an implantation site, the fixation element being one or a combination of more than one of barbs, traction.

4. The interventional valve of claim 3, wherein the fixture is of unitary construction with the valve frame.

5. The interventional mitral valve of claim 3, wherein the barbs are located at a support site where the leaflets are coaptally fixed on the valve frame.

6. The interventional mitral valve of claim 3, wherein the securing member is of a self-contained construction that is fixedly attached to the rest of the valve frame after machining.

7. The interventional mitral valve of claim 1, wherein the atrial portion of the valve frame is one or a combination of more than one of a flange structure, a conical surface structure, a spherical structure.

8. The interventional mitral valve of claim 1, wherein between the atrial portion and the ventricular portion is a corset mechanism having a smaller diameter than the ventricular portion and the atrial portion, the corset mechanism causing the interventional valve to clip onto an annulus of a native valve.

9. The interventional mitral valve of claim 1, wherein the valve frame is provided with a flexible contact surface or rigid isolation structure that reduces damage to and/or interference with the leaflets of the interventional mitral valve when the natural leaflets are closed.

10. The interventional mitral valve of claim 1, wherein the struts are inverted triangular in shape from top to bottom.

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