Heart valve prosthesis and method for manufacturing heart valve prosthesis

Abstract

The present invention relates to a heart valve prosthesis (100) for implantation into the heart of a patient, wherein the heart valve prosthesis (100) comprises: a stent frame (102) and a plurality of units arranged in circumferential rows; a valve element (120) mounted to the heart valve prosthesis (100) and comprising at least two, preferably three leaflets (121); a skirt (130) attached to the stent frame (102), where the skirt (130) comprises a skirt body (131) and at least two, preferably three, skirt flaps (132) integral with or attached to the skirt body (131), where the skirt body (131) covers at least the nearest row unit (110) of the stent frame, where each skirt flap forms a decoupling element (99) in a folded state, and wherein each skirt valve (132) covers one of the commissure units (117) of the distal-most units (114) of the stent frame, and wherein the leaflets (120) are mounted to the heart valve prosthesis (100), respectively, within the commissure units (117) of the distal-most units (114) by decoupling elements (99).

Description

Technical Field

[0001] The present invention relates to a heart valve prosthesis for implantation into a body cavity, in particular by transluminal delivery. The heart valve prosthesis presented herein is particularly suitable for replacing a natural heart valve in a patient, and the present invention also relates to a method for preparing or manufacturing the heart valve prosthesis. Background Art

[0002] Heart valve disease remains a significant cause of morbidity and mortality, and replacement of diseased native heart valves with heart valve prostheses has become a routine surgical procedure for patients with valvular regurgitation or leaflet stenosis and calcification.

[0003] Heart valve replacement is required in cases where the native heart valves are damaged, malfunctioning or non-functioning. In the heart, the heart valves maintain a one-way flow of blood by opening and closing according to the pressure difference on each side. The mammalian heart contains four chambers, two atria, which are filling chambers, and two ventricles, which are pumping chambers. There are four heart valves in the mammalian heart, which normally allow blood to flow through the heart in only one direction, whereby the heart valves open or close according to the differential blood pressure on each side.

[0004] The four main valves in the heart are the mitral valve (equivalent to the bicuspid valve) and the tricuspid valve, which are between the upper atrium and the lower ventricle, respectively, and are therefore called atrioventricular (AV) valves. In addition, there are the aortic valve and the pulmonary valve, which are in the arteries leaving the heart. The mitral valve and the aortic valve are in the left heart, and the tricuspid valve and the pulmonary valve are in the right heart.

[0005] The valves consist of leaflets or cusps, each of which has three cusps, except for the mitral valve, which has only two. For example, the aortic valve is made up of three leaflets, where the leaflet cusps are named the Right Coronary Cusp (RCC), the Left Coronary Cusp (LCC), and the Non-Coronary Cusp (NCC). Each cusp has two commissures that are shared with the adjacent cusps. The commissures are the spaces or areas where the two leaflets adjoin and fuse with the aortic wall. They act as supports for the cusp infrastructure.

[0006] Ideally, the natural leaflets of a heart valve move away from each other when the valve is in the open position, and meet or "coapt" when the valve is in the closed position. As a result, heart valves can be affected by a range of diseases and may therefore require heart valve replacement surgery. The valve may leak, i.e., regurgitate or insufficiency, in which case the aortic valve is not functional and blood passively flows back into the heart in the wrong direction. In addition, the valve may partially close, i.e., stenosis, in which case the valve cannot fully open, thereby hindering blood flow from the heart. These two conditions often exist together.

[0007] Until recently, the vast majority of heart valve replacements required a complete sternotomy and placement of the patient on cardiopulmonary bypass. Traditional open surgery causes significant patient trauma and discomfort, requires extensive recovery time, and can result in life-threatening complications. To address these concerns, efforts have been made over the past two decades to perform heart valve replacements using minimally invasive techniques (e.g., percutaneous access and transluminal delivery). These percutaneous heart valve replacement treatments utilize the lumen of the patient's vascular system and use a catheter to deliver the valve prosthesis to the diseased site.

[0008] Generally speaking, there are two types of prosthetic heart valve devices used in the industry to replace defective natural heart valves, namely mechanical prosthetic valve devices and bioprosthetic valve devices. Bioprosthetic valve devices use natural tissue (usually mammalian, such as porcine or bovine origin) to form the foldable leaflets of the bioprosthetic valve device.

[0009] Despite the great efforts invested in developing heart valve prostheses, existing valve prostheses have many disadvantages, including premature failure due to wear, complexity of manufacturing and less than ideal performance, which are present in both the valve assembly and the frame of existing heart valve prostheses. For example, less than ideal leaflet design can lead to poor sealing of fluid channels and / or undesirable overlap and / or curling of foldable leaflets during the closed state. In addition, when inserting a frame that can serve as a stent assembly, there is usually a lack of sufficient structural support for the commissure and / or a suitable geometry for properly anchoring the valve assembly. A major disadvantage of most percutaneous heart valve prostheses is that they lack flexible attachment of leaflets to the support structure (i.e., stent frame). Surgical implant prostheses that incorporate flexible parts in the commissure attachment point area have been developed. It has been shown that this feature improves the overall durability of the prosthesis by reducing the stress level that remains in the leaflet and cannot be dissipated by the flexible support structure. Incorporating this feature into percutaneous heart valves (and especially balloon-expandable percutaneous heart valves) is far more challenging than surgical implant prostheses.

[0010] It is crucial for a fully functional heart valve prosthesis that all its components fulfill their respective tasks: On the one hand, the valve needs to be adequately attached to the frame / stent support, because otherwise the valve is prone to failure and valve failure in the circulatory system has significant consequences for the patient. On the other hand, the stent support needs to be fully expanded and thereby ensure a secure fixation within the heart vessels.

[0011] Furthermore, loading the valve onto a minimally invasive deployment system can be very challenging, as heart valve prostheses by their nature require careful loading, while at the same time their compression is mandatory for tightly packing them onto the deployment system.

[0012] Therefore, there is a need for improved heart valve prosthetic devices and methods of making the same. Summary of the invention

[0013] According to the present invention, this and other objects are solved by a heart valve prosthesis for implantation in a patient's heart, wherein the heart valve prosthesis comprises: a stent frame comprising a lumen, a luminal side and an abluminal side and a plurality of cells arranged in circumferential rows, wherein the plurality of cells comprises at least a closest row of cells, at least one (preferably two, three, four or five) middle row of cells and a farthest row of cells; a valve element mounted to the heart valve prosthesis and comprising at least two, preferably three leaflets; a skirt attached to the stent frame, wherein the skirt comprises a skirt body and at least two, preferably three skirt flaps integral with or attached to the skirt body, wherein the skirt body covers at least the closest row of cells, preferably on the lumen side, wherein each skirt flap covers a corresponding commissure cell in the farthest row of cells, thereby forming a decoupling element. element), and wherein the leaflets are mounted to the heart valve prosthesis within the commissure unit in the most distal row unit via respective decoupling elements.

[0014] With the heart valve prosthesis of the present invention, or more precisely, due to the specific design, i.e., the decoupling element with specific flexibility provided in the heart valve prosthesis of the present invention, a commissure with defined flexibility is produced, i.e., a flexible attachment of the valve is achieved through the commissure of the leaflets. Compared with known heart valve prostheses in which the commissure is usually fixed / sutured to the stent frame, this design provides a better and more flexible function for the valve as a whole; in addition, since the commissure has a customized flexibility, the tensile stress (tensioning stress) applied to the valve is reduced when it is dissipated by the flexible decoupling element, which generally leads to a longer life of the prosthetic device / heart valve prosthesis.

[0015] Currently, the use of a "decoupling element", i.e. an element with limited flexibility, means that: through this element, the fixation of the leaflet is decoupled from the stent frame or stent support, so that it is not directly attached or fixed (for example, sutured) to the stent frame or part of the stent frame, thereby decoupling the mechanical load of the joint and the leaflet from the stent frame.

[0016] According to one embodiment of the invention, the decoupling element is formed by each petal in a folded state, ie a state in which the petal is bent so that one part of the petal rests on another part.

[0017] Thus, a defined or specific flexibility of the decoupling element may be achieved, for example, by using specific materials for the petals.

[0018] Therefore, in one embodiment, the skirt has a defined flexibility, wherein the defined flexibility is defined by: a Young's modulus / tensile modulus of 50 to 3000 MPa, preferably 100 to 500 MPa, tested with a uniaxial tensile tester according to ISO527-1. In the case of this defined flexibility, the mechanical load borne by the leaflet can be decoupled from the stent frame.

[0019] In this article, and as generally understood, Young's modulus is understood as the elastic modulus in tension or compression (i.e., negative tension) and is a mechanical property that measures the tensile or compressive stiffness of a solid material when a force is applied longitudinally. Therefore, Young's modulus indicates a specific flexibility. Young's modulus is a mechanical material property commonly known in engineering design, and particularly in materials science / development. For example, one method for determining Young's modulus / tensile modulus is to apply a tensile test standard, in which Young's modulus is defined as the ratio of stress to strain during elastic loading and can be determined according to ISO 527-1 or ISO 13934-1. In one embodiment, the determination of Young's modulus can be performed, for example, by the following method: the decoupling element is installed in a uniaxial tensile testing machine and pulled to the end of the elastic limit, i.e., yield strength. The proportionality coefficient of the stress and strain obtained gives the elastic modulus, i.e., Young's modulus.

[0020] This defined flexibility can be achieved, for example, by using a specific material for the petals, as defined below. Furthermore, the material used for the petals can be the same or different from the material used for the skirt body. Furthermore, the petals can contain additional material to locally reinforce the decoupling element formed by the petals.

[0021] In one embodiment of the heart valve prosthesis of the present invention, since the skirt has a limited flexibility, the decoupling element also has a specific flexibility, which can also be represented by a Young's modulus, which is similar / identical to the Young's modulus of the skirt (in the absence of reinforcement between the skirt) and / or is preferably 50 to 3000 MPa, preferably 100 to 500 MPa, and more preferably 150 to 300 MPa.

[0022] By means of a decoupling element (or uncoupling element), a mechanism is provided which allows for flexible attachment of the leaflets in a heart valve prosthesis device, which in turn results in a better function of the valve as a whole: the flexible valve element cannot dissipate the mechanical loads into the rather stiff stent frame when closed, but the decoupling element allows this transfer of mechanical loads into the stent frame. By reducing the stress level in the leaflets, the life of the valve is thus extended.

[0023] For now, and as is generally understood, terms relating to cardiac anatomy have the same meanings as generally understood in the art, as discussed in part at the beginning of this disclosure.

[0024] In addition, and as generally understood in the art, the term "skirt" used in the present invention means a sealing system attached to the stent frame to prevent paravalvular leaking, usually a thin layer / membrane made of biological or artificial materials. The attachment of the skirt to the stent frame is usually achieved by suturing or chemically attaching the skirt frame to the stent frame.

[0025] For definition purposes and in accordance with the present invention, a "stent" or "stent frame" refers to a structural component that can be anchored in the tissue of an annular heart valve space. The stent frame is typically and preferably formed of a biocompatible metal frame (e.g., stainless steel or Nitinol), and can be, for example, laser cut or braided, or otherwise made of interwoven wire filaments. Other stents that can preferably be used with the valve of the present invention include rigid rings, spirally wound tubes, and other such tubes that are closely arranged in the annular valve space and define an orifice for blood to pass through. The stent frame typically and preferably has a tubular or hollow cylindrical shape.

[0026] In the present invention, and as generally understood, "valve" or "valve member / element" refers to a component of a heart valve that has a fluid blocking surface to prevent blood from flowing in one direction and allow blood to flow in another direction, as described above; a variety of valve member configurations are available, including those with flexible leaflets and those with rigid leaflets, or even a ball and cage arrangement. The leaflets may be bioprosthetic, synthetic, metallic, or other suitable means.

[0027] The terms "about" or "approximately" as used herein apply to all numerical values, whether or not explicitly stated. These terms generally refer to numerical ranges that are considered by those skilled in the art to be equivalent to the recorded values ​​(i.e., having the same function or result). In many cases, these terms may include numbers rounded to the nearest significant figure. The terms "substantially" and "substantially" or "essentially" as used herein mean that when the various parts are compared to each other, the compared parts are equal or close enough in size that those skilled in the art would consider to be the same. The basic and substantially and essentially used herein are not limited to a single size and specifically include the range of values ​​of those parts being compared. The range of values ​​in these two cases of being higher and lower (e.g., more / less than or greater / less than) includes the range of variation of reasonable tolerances for the mentioned parts known to those skilled in the art.

[0028] As used herein, the terms "integrally formed" or "unitary" and "unitary construction" refer to a construction that does not include any welds, fasteners, or other means for securing separately formed material components to one another.

[0029] Furthermore, as used herein, when referring to the skirt body and the skirt flaps, "directly attached to" means a direct connection of the skirt body and the skirt flaps. For example, a skirt body of a first material may be attached to a skirt flap made of a different material. Thus, "attachment" includes means for securing separately formed components of the same or different materials to each other.

[0030] In the context of the present invention, the terms "near" and "far" are used interchangeably with the terms "inflow" and "outflow", respectively, so that, for example, the "nearest" cells of a stent frame are the cells at the (blood) inflow end, and the farthest cells are the cells at the (blood) outflow end of the stent frame. In other words, the nearest row of cells is the last row of cells at the proximal end of the stent frame, and the farthest row of cells is the last row of cells at the distal end of the stent frame. Therefore, the stent frame includes a proximal (inflow) end and a far (outflow) end. Therefore, for example, the heart valve prosthesis illustrated in Figure 1 is shown in a direction associated with an implanted heart valve, and therefore the nearest row of cells of the stent frame represents the cells at its inflow end, and the farthest row of cells of the stent frame represents the cells at its outflow end.

[0031] The term "unit" as used herein refers to a closed compartment in a stent framework, forming a "hole" in the stent framework (if not covered by a prosthetic material attached to the stent framework), and the unit can be formed in different shapes by surrounding stent materials or stent struts. A row of units refers to a series of units directly adjacent to each other seen in the circumferential direction of a tubular stent framework, wherein adjacent units share a common edge or strut with the unit adjacent to the left or right in the unit.

[0032] A "skirt flap" within the meaning of the present invention is a piece of skirt extending from the main body of the skirt and which is attached / integral to the main body of the skirt on only one side and which extends freely on the other side.

[0033] According to a preferred embodiment of the invention, the decoupling element functions in such a way that the leaflets are mounted to the heart valve prosthesis via the decoupling element in the commissure unit in the most distal row of units each covered by a flap. In this way, the flap of the covering unit functions as a decoupling element.

[0034] In this embodiment, advantageously, the skirt covering the commissure unit in the most distal row of units serves as the attachment zone; since the skirt itself has a certain flexibility, the leaflet also retains its flexibility after attachment to the skirt.

[0035] Furthermore, according to the present invention, the leaflets do not contact the stent frame at the commissure level.

[0036] According to one embodiment of the heart valve prosthesis according to the invention, each petal comprises an opening such that the opening is located within a commissure unit respectively covered by each petal.

[0037] This embodiment has the advantage that, through the openings, the leaflets can be attached to the petal while maintaining the flexibility of the petal and the flexibility of the attachment thereto.

[0038] In one embodiment of the heart valve prosthesis of the present invention, the skirt body is attached to the stent frame on the luminal side.

[0039] In one embodiment of the heart valve prosthesis of the present invention, the skirt body is preferably attached to the luminal side of the stent frame, and preferably, each skirt flap includes a first part and a second part, the first part is attached to the luminal side of the stent frame and includes an opening, the opening is located in the at least one commissure unit, and preferably, the second part is designed to fold over the farthest edge of the commissure unit from the luminal side of the stent frame to the luminal outside of the stent frame, so that the second part is attached to the stent frame extraluminally, thereby at least partially covering the opening.

[0040] In this embodiment, the skirt also serves as an attachment means for the leaflets: the leaflets can be guided from the luminal side of the stent frame through the openings in the first part of the skirt covering the unit, respectively, and the second part can be folded over the farthest edge of the commissure unit, thereby at least partially covering the openings and the commissure unit, and the second part can be folded from the luminal side of the stent frame to the outside of the luminal side. Thus, an even more stable and flexible attachment of the leaflets can be achieved.

[0041] Thus, in one embodiment, a first portion of the skirt is attached to the stent frame on the luminal side of the stent frame and a second portion of the skirt is on the luminal side of the stent frame.

[0042] In another embodiment, each skirt flap includes a first part and a second part, the first part is attached to the tubular cavity side and includes an opening, the opening is located in the at least one connecting unit, and preferably, the second part is designed to be folded around the side struts of the connecting unit from the tubular cavity side of the stent frame so that the second part is attached to the stent frame extraluminally, thereby at least partially covering the opening.

[0043] In another embodiment, the skirt body is attached to the luminal side of the stent frame, and each skirt flap includes a first portion and a second portion, wherein the first portion is attached to the outside of the luminal side, and wherein the second portion is designed to be folded around the side struts of the commissure unit from the outside of the luminal side of the stent frame to the luminal side of the stent frame, so that the second portion is luminally attached to the stent frame, so that an opening is formed on the luminal side.

[0044] Therefore, in one embodiment of the heart valve prosthesis of the present invention, each leaflet includes a leaflet body and a leaflet flap, wherein the leaflet body is arranged in the tubular cavity of the stent frame, and the leaflet flap is guided from the tubular cavity side of the stent frame to the outside of the tubular cavity through an opening located in the unit covered by the skirt flap, for fixing each leaflet at / through the decoupling element.

[0045] In one embodiment of the heart valve prosthesis of the invention, the most distal cell comprises at least two, preferably three commissure cells spaced apart from one another by spacing cells, wherein the commissure cells are longer than the spacing cells and thus protrude in the distal direction D.

[0046] In the case of this embodiment, or more precisely, in the case of a particular commissure unit, the anatomy of the heart can be addressed. By providing only two or three longer commissure units, the farthest edge of the heart valve prosthesis does not uniformly cover the site of the blood vessel where the prosthesis is placed circumferentially; instead, by means of shorter separation units, spaces are created between the longer commissure units, allowing for the de-branching arteries, such as the coronary arteries, to be left open.

[0047] Therefore, in a preferred embodiment, the most distal row of cells comprises three commissure cells, each separated from one another by three separation cells, the commissure cells being longer than the separation cells.

[0048] In the present invention, the term "longer" means that the commissure unit protrudes about a certain length x in the distal direction compared to the shorter separation unit. The length x may be about 2 mm to about 8 mm, preferably less than or equal to 5 mm.

[0049] Furthermore, in the present invention, the term "commissure cell" refers to a cell that serves as an attachment area for the leaflets of a valve element, thereby creating commissures of the valve element. Thus, a "separation cell" refers to a cell in the farthest row that separates commissure cells from each other.

[0050] In one embodiment of the invention, the joining units have a substantially diamond shape, and optionally, wherein the separating units have a substantially triangular shape.

[0051] This specific design of the commissure and separation units also provides a stent frame design by which the distal portion of the heart valve prosthesis is allowed to be firmly anchored in the area of ​​the native valve, while ensuring that the replacement valve elements can function fully without the debranched arteries being blocked by the prosthesis.

[0052] In one embodiment of the heart valve prosthesis of the present invention, the proximalmost row of cells comprises cells having a substantially heart-shaped shape.

[0053] With this design of the shape of the nearest row of cells, an overall better adjustment and better sealing to the heart wall can be achieved. Furthermore, with the specific heart-shaped cells, radial forces are reduced, which advantageously avoids stimulation interruptions.

[0054] In one embodiment of the heart valve prosthesis of the invention, the stent frame comprises at least one intermediate row directly adjacent to the most distal row, which preferably comprises cells having a substantially triangular shape.

[0055] In the case of such a triangular shaped unit, an asymmetric design of the unit is created, allowing the unit to additionally keep a debranched artery (eg a coronary artery) open.

[0056] According to a preferred embodiment, the number of cells of the intermediate row directly adjacent to the farthest row comprises 6 to 16 cells, i.e. 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16 cells, preferably 12 cells.

[0057] In one embodiment of the heart valve prosthesis of the invention, the stent frame comprises a first intermediate row directly adjacent to a nearest row, which preferably comprises cells having a substantially hexagonal shape.

[0058] In one embodiment of the inventive heart valve prosthesis, the stent frame comprises a second intermediate row directly adjacent to the first intermediate row, wherein preferably the second intermediate row comprises cells having a substantially hexagonal shape.

[0059] Preferably, the stent frame comprises a second intermediate row directly adjacent to the first intermediate row, said second intermediate row preferably comprising cells having a substantially hexagonal shape.

[0060] In one embodiment of the present invention, the first intermediate row and the second intermediate row each comprise 6 to 16 cells, preferably each comprise 10 to 12 cells, more preferably each comprise 12 cells.

[0061] In one embodiment of the heart valve prosthesis of the invention, the first intermediate row and the second intermediate row comprise symmetrical cells.

[0062] One embodiment of the heart valve prosthesis of the present invention includes a stent frame having five rows of cells: a farthest row of cells, three middle rows of cells and one closest row of cells, wherein the farthest row of cells and the closest row of cells include cells having shapes as defined above, and wherein the three middle rows include cells having shapes as defined above, a middle row directly adjacent to the farthest row (in the proximal direction), a first middle row directly adjacent to the closest row (in the distal direction), and a second middle row adjacent to the first middle row (in the distal direction).

[0063] In one embodiment of the heart valve prosthesis of the present invention, the skirt, i.e. the skirt flap and / or the skirt body comprises a fabric, membrane or tissue material with defined and preferably uniform flexibility, and preferably comprises a material selected from polyester, polyurethane, polytetrafluoroethylene (PTFE).

[0064] By providing a material with a specific and uniform flexibility, a specific flexibility of the decoupling element as discussed above is ensured and as a result a secure attachment of the leaflets with a defined flexibility is achieved.

[0065] The valve element or more precisely the leaflets of the valve element are preferably produced from mammalian pericardium.

[0066] In one embodiment of the heart valve prosthesis of the present invention, the stent frame is balloon expandable or self-expanding.

[0067] The self-expanding stent frame can be curled or otherwise compressed into a small tube and has sufficient elasticity to expand by itself when a restriction (e.g., an outer sheath) is removed. In contrast, the balloon-expandable stent frame is made of a material that is substantially less elastic and must be plastically expanded from the inside to form when it is converted from a contracted diameter to an expanded diameter. It should be understood that the term "balloon-expandable stent frame" includes a plastically expandable stent frame, whether or not a balloon is used to actually expand it (e.g., a device with a mechanical finger can expand the stent frame). The stent frame material is plastically deformed after a deforming force such as an inflatable balloon or a mechanical expansion finger is applied. Therefore, the term "balloon-expandable stent" should be understood to refer to the material or type of the stent frame, rather than a specific expansion medium.

[0068] The invention also relates to a method for manufacturing a heart valve prosthesis, the method comprising the following steps:

[0069] - providing a stent frame, the stent frame comprising a lumen, a lumen side and a lumen side, and a plurality of cells arranged in circumferential rows, wherein the plurality of cells comprises at least a proximal row of cells, a middle row of cells and a distal row of cells;

[0070] - attaching, preferably suturing, a skirt to the stent frame, wherein the skirt comprises a skirt body and at least two, preferably three, skirt flaps integral with the skirt body, such that the skirt body covers at least the most proximal row of cells on the luminal side of the stent frame, and each skirt flap has a respective first portion and a second portion, the first portion comprising an opening, covering cells in the most distal row of cells on the luminal side of the stent frame, and the second portion extending along the most distal edge of the covered cells;

[0071] - attaching at least two, preferably three leaflets to the stent frame, wherein each leaflet comprises a leaflet body and a leaflet flap, the leaflet body being disposed within the lumen of the stent frame, and the leaflet flap being guided from the lumen side of the stent frame to the outside of the lumen through the opening of the first portion of the skirt flap;

[0072] - folding the corresponding second portion of the flap over the outermost edge of the covered unit so as to at least partially cover the leaflet and the opening with the second portion;

[0073] - Attaching the second skirt portion to the stent frame, thereby securing the leaflets to the stent frame via the decoupling element.

[0074] With the method provided herein, a secure attachment of the valve element within the stent frame is ensured, while at the same time a flexible attachment of the valve is achieved, allowing an optimized stress distribution and thus making the valve run and function as naturally as possible.

[0075] In the heart valve prosthesis and method of the present invention, the expression "fixing / fixating the leaflet to the stent frame by means of a decoupling element" means that the leaflet is not directly attached to the stent frame, but is directly attached to the decoupling element (and indirectly attached to the stent frame), which in turn forms an integral part / connected with the stent frame.

[0076] In one embodiment of the method of the invention, each leaflet comprises two petals which are guided through the opening in a folded state and which, after passing through the opening, unfold and are subsequently covered by the second portion of the skirt.

[0077] Furthermore, in one embodiment of the method of the present invention, a heart valve prosthesis as disclosed above is manufactured.

[0078] The heart valve prosthesis / prosthetic device of the present invention is suitable for / for replacing any valve of a mammalian patient's heart (preferably a human, preferably an adult heart), namely the aortic valve, pulmonary valve, mitral valve and tricuspid valve, wherein replacement of the aortic valve is preferred.

[0079] Therefore, the present invention also relates to a method for treating a defective natural valve in the heart of a mammal (preferably a human) to replace the function of the natural valve, wherein the natural valve is preferably an aortic valve, wherein the method for treatment comprises the following steps: - advancing the heart valve prosthesis disclosed above through the patient's vascular system along the blood vessel wall to the treatment site; - (i) expanding the expansion member within the stent frame so that the stent frame expands and contacts the blood vessel wall, or (ii) withdrawing the sheath that maintains compression of the heart valve prosthesis so that the stent frame expands and contacts the blood vessel wall when the sheath is withdrawn.

[0080] It should be understood that the features described above and the features still to be described below fall within the scope of the invention not only in the respective specified combinations, but also in different combinations or by themselves, so that the present disclosure should also be considered to specifically relate to other embodiments with any other possible combination of the features of the dependent claims. For example, for the purpose of claim disclosure, if the multiple dependency format is an acceptable format in the jurisdiction, any subsequent dependent claim should be deemed to be written alternatively in such multiple dependency form based on all preceding claims, which have all prerequisites cited in such dependent claims (for example, each claim directly dependent on claim 1 should be deemed to be dependent on all preceding claims instead). In jurisdictions where the multiple dependent claim format is restricted, the following dependent claims should also be deemed to be written alternatively in each individual dependent claim format, which format creates a dependency on the claim with the prior prerequisite, rather than the specific claim listed later in such dependent claims.

[0081] Some preferred embodiments are shown in the drawings and are described in further detail below. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] In the attached picture:

[0083] Fig. 1 shows schematic diagrams of modes of a stent frame of one embodiment of a heart valve prosthesis of the present invention, with the outline of the tubular form being flattened in different ways, without a valve in a first view (A) and with a schematic outline of an attached valve (B), and a view of the stent frame in tubular form (C);

[0084] Figure 2 A schematic diagram showing a skirt element for one embodiment of a heart valve prosthesis of the present invention, the skirt element being flattened and not attached to a stent frame;

[0085] FIG3 shows schematic diagrams of leaflets of a valve element of an embodiment of a heart valve prosthesis of the present invention, which are two different shapes of a single leaflet (A) and (B);

[0086] FIG4 shows an enlarged view of a portion of a stent frame and a portion of a method for making a heart valve prosthesis of the present invention, wherein a skirt is attached to a stent frame of one embodiment of a heart valve prosthesis of the present invention, wherein the skirt body covers the most proximal and intermediate rows of the stent frame, wherein a first portion of the skirt flap covers cells in the most distal row of cells of the stent frame without being folded over and without directing the leaflets through the opening (A); wherein the leaflets are partially directed through the opening and a second portion of the skirt flap is not folded over (B); and the second portion of the skirt flap is folded over the edge of the cell covered by the first portion (C);

[0087] Figure 5 shows a schematic diagram of a cross-section of a portion of a stent frame of an embodiment of a heart valve prosthesis of the present invention, wherein the leaflet flap is partially guided through an opening in a first portion of a skirt flap that covers the cells in the farthest row of the stent frame; (A) shows an embodiment in which the second portion of the skirt flap is folded over the farthest edge of the commissure cell without being wrapped around the struts of the commissure cell of the stent frame; (B) shows an embodiment in which the second portion of the skirt flap is folded over the farthest edge of the commissure cell, wherein the flap is wrapped around the struts of the commissure cell of the stent frame; and (C) shows an embodiment in which the second portion of the skirt flap is folded over the farthest edge of the commissure cell, wherein the flap is wrapped around the struts of the commissure cell of the stent frame, and wherein the second portions of the flap are separated and overlap each other.

[0088] FIG6 shows a schematic diagram of the mechanism of the decoupling element, with a front view (A) and a cross section through the stent frame (B); and

[0089] Figure 7 A diagram of one embodiment of an assembled heart valve prosthesis of the present invention is shown in perspective view. DETAILED DESCRIPTION

[0090] The accompanying drawings, which are incorporated herein and constitute a part of the specification, also serve to explain the principles of the invention and to enable one skilled in the relevant art to make and use the invention. The drawings are not drawn to scale.

[0091] Some specific embodiments of the present invention are now described with reference to the accompanying drawings, wherein the same reference numerals represent the same or functionally similar elements. The following detailed description is merely exemplary in nature and is not intended to limit the present invention and the uses of the present invention. In addition, it is not intended to be bound by any express or implied theory presented in the aforementioned technical field, background technology, summary of the invention or the following detailed description.

[0092] FIG. 1 shows schematic diagrams of a stent frame 102 of one embodiment of a heart valve prosthesis 100 of the present invention in 1A and 1B, wherein the tubular closed form is flattened / opened in different ways. Figure 1A As can be seen in the figure, the stent frame 102 includes a plurality of circumferential rows 110, 111a, 111b, 112, 114, having a nearest row 110, a farthest row 114, an intermediate row 112 directly adjacent to the farthest row 114 (in the proximal direction P), a first intermediate row 111a directly adjacent to the nearest row 110 (in the distal direction D), and a second intermediate row 111b directly adjacent to the first intermediate row 111a.

[0093] As in Figure 1A , 1B1C, the nearest row 110 includes cells having a substantially heart-shaped shape. As a result of the heart-shaped shape, in the embodiment shown here, the cells in the nearest row 110 are larger / have larger openings than the first and second intermediate rows 111a, 111b.

[0094] The heart shape is exemplary only, and other shapes may be used to achieve the same purpose, namely better attachment and sealing to the heart wall.

[0095] In the embodiment shown in FIG. 1 , the cells of the first intermediate row 111a and the second intermediate row 111b have a substantially hexagonal shape and are smaller than the cells of the nearest row 110. As a result, the number of cells contained in the first row 111a and the second row 111b is also greater. In FIG. 1 , in particular Figure 1C In the embodiment shown in , the number of cells in the nearest row is 6, and the number of cells in the first intermediate row 111a and the second intermediate row 111b is 12, respectively. However, it should be understood that the number of cells is merely exemplary; other numbers / ranges may also be used to achieve the same purpose.

[0096] In the embodiment depicted in Fig. 1, the cells of the most distal row 114 include cells in which three larger cells (also referred to as commissure cells 117) are spaced apart from each other by respective spacing cells 118. In the embodiment shown in Fig. 1, the three commissure cells 117 are separated from each other by respective spacing cells 118. The commissure cells 117 are larger / longer than the spacing cells 118 and thus protrude in the distal direction D compared to the shorter spacing cells 118. The commissure cells are longer than the length L of the shorter spacing cells, or in other words, the length L protruding from the shorter spacing cells is about 2 mm to about 2 cm, preferably 2 mm to 8 mm.

[0097] The three commissure cells 117 represent cells 117 in which the commissures are installed (via skirts, see description below). The two rows 111b and 111a induce radial forces for securing the heart valve prosthesis at the implantation site.

[0098] In the embodiment shown in FIG1 , the nearest row of cells 110 includes 6 heart-shaped cells, thus providing lower radial forces and higher flexibility to better fit the annulus of the native heart valve to be replaced. The different shapes of the cells of the row affect different gradients of the struts that interconnect the cells. By having different gradients, radial forces are reduced to avoid disruption of stimulation.

[0099] Figure 1BAlso schematically depicted are the attachments of the commissures (via skirt 130; not shown in FIG. 1; but see description below), represented by three crosses x, and the attachments of the contours of the valve leaflet VL / semilunar junctions: the apex x is within the commissure cell 117, and the nadir is at 111c between two cells in the first intermediate cell row 111a above the nearest or inflow row 110.

[0100] Commissure cells 117 of the most distal row of cells 114 of heart valve prosthesis 100 shown in FIG. 1 have a substantially diamond shape, and septal cells 118 have a substantially triangular shape.

[0101] exist Figure 1C , the stent frame 102 is shown in its tubular shape, thus having a lumen 103, a luminal side 104, and an aluminal side 105. As can also be seen in this figure, the stent frame 102 of this embodiment includes 5 rows of cells, the most proximal row representing the inflow end of the stent frame 102, and the most distal row 114 representing the outflow end of the stent frame 102.

[0102] Figure 2 A schematic diagram of the skirt 130 is shown, which, in the assembled state of the heart valve prosthesis 100, is attached / arranged on the luminal side 104 of the stent frame 102 together with its body 131 and the first part 133 of the skirt flap 132. Figure 1A and 1B The support frame 102 is not shown for better understanding. Figure 2 The skirt 130 in FIG. 1 is attached to the stent frame 102 and is also not shown in tubular form, but rather in an open / flattened form.

[0103] As from Figure 2 As can be seen in the figure, the skirt includes a skirt body 131 and three skirt petals 132, which are integrally formed with the skirt body 131 and extend from the skirt body 131 in the distal direction D. In the assembled state of the heart valve prosthesis of the present invention, the three skirt petals 132 cover the three commissure units 117 of the farthest row 114 of the stent frame 102.

[0104] Each skirt flap 132 comprises a first portion 133 and a second portion 134, respectively. The respective first portion 133 comprises an opening 135 (or window or hole) which, in the assembled state of the heart valve prosthesis of the present invention, i.e., in the case where the skirt 130 is attached to the stent frame 102, is located within the cell 117 (i.e., the commissure cell). In order to assemble the heart valve prosthesis of the present invention, the skirt 130 is attached to the luminal side 104 of the stent frame 102, wherein the skirt body 131 covers at least the cells of the nearest row 110 from the inside of the lumen 103. The respective second portions 134 of the skirt flaps 132 are designed so that they can be folded over the most distal edge 116 of the commissure cell 117 (see FIG. 1 ) from the luminal side 104, so that the second portions 134 are attached to the stent frame 102 extraluminally. The assembly of the skirt 130 to the stent frame is shown in more detail in FIG. 4 , which will be further described below.

[0105] like Figure 2 The schematic diagram of the skirt 130 shown in illustrative figures shows that the proximal-most contour 136 or shape of the skirt 130 conforms to the contour of the proximal-most contour 113 of the stent framework 102 .

[0106] Thus, in the assembled state of the heart valve prosthesis 100 of the present invention, the skirt is attached to the entire height of the stent frame 102 .

[0107] FIG. 3 depicts a valve element 120 of one embodiment of a heart valve prosthesis 100 of the present invention (see Figure 7 ) are schematic diagrams of a leaflet 121, exemplarily showing two different shapes (A) and (B) of a single leaflet 121, not attached to a stent frame 102.

[0108] As shown in Fig. 3, each leaflet 121 includes a leaflet body 123 and two leaflet flaps 122 or wings. The leaflet body 123 is disposed within the lumen 103 of the stent frame 102, and the leaflet flaps 122 are guided through openings 135 in the skirt flaps 132 and within the corresponding commissure units 117 covered by the skirt flaps 132, from the lumen side 104 of the stent frame 102 to the lumen side 105 for securing each leaflet 121 to the stent frame 102 via the decoupling element 99. The leaflet flaps 122 are formed and designed so that they can be guided through the openings 135 of the skirt flaps 132, as will be described below with respect to Fig. 4.

[0109] As in Figure 3A , 3B As can be seen in FIG. 1 , the shape of the leaflet petals 122 has a rounded free edge below the petals 122. The leaflet petals 122 have inclined edges 125 corresponding to the cells of the stent frame.

[0110] FIG. 4 shows an enlarged view of a portion of stent frame 102 and illustrates a portion of the steps of a method for manufacturing heart valve prosthesis 100 according to one embodiment of the present invention. Figure 4A The alignment of the skirt 130 in the luminal side 104 of the stent frame is shown such that the skirt body 131 covers the most proximal row 110 as well as the first intermediate row 111a and the second intermediate row 111b within the lumen 103. As can be seen in FIG. 4 , the first portion 133 of the respective skirt flap 132 covers the commissures 117 of the most distal row 114 of the stent frame 102 such that the opening 135 is located in the commissures 117. In this step, the second portion 134 of the skirt flap 132 extends beyond the most proximal edge 116 of the commissures 117 in the distal direction D. In other words, the second portion 134 of the skirt flap 132 has not yet been folded over the most proximal edge 116 of the commissures. Furthermore, the leaflets 121, or more precisely, the leaflet flaps 122 or wings have not yet been guided through the openings / holes 135 located in the commissures 117.

[0111] In the next step, Figure 4B As shown in the figure, the leaflet 121 or more precisely, the leaflet flap 122 is guided or pushed from the luminal side 105 of the stent frame 102 through the opening 135 located in the joint unit 117, and is folded to the right and left sides of the opening 135 respectively, and is thus guided to the luminal outside 105 of the stent frame 102.

[0112] Figure 4C It is shown that in a subsequent step, the second portion 134 of the skirt flap 132 is folded over the nearest edge 115 of the commissure unit 117 so that it at least partially covers the opening 135 and the leaflet flap 122. Subsequently, the second portion in this position can be attached (e.g., sutured) to the stent frame 102 on the luminal outside 105 of the stent frame 102, thereby fixing the leaflet in the prosthetic heart valve. With this unique fixing method, the leaflet does not contact the stent frame 102.

[0113] By the attachment method for the leaflets shown in FIG4 , and as described therein, the leaflets are decoupled from the stent frame, providing improved flexibility of the valve element. Thus, the combination of the skirt 130 with a first portion 133 of the skirt flap 132 covering the commissure unit 117 and including the opening 115, and a second portion 134 of the leaflet flap 122 folded over and directed through the opening 115 provides a decoupling element 99 (see FIG6 ).

[0114] In Fig. 5, different embodiments for forming a decoupling element 99 with respect to the stent frame 102 by means of the skirt flaps 132 and for attaching the skirt / flaps to the stent frame are shown.

[0115] therefore, Figures 5A to 5CSchematic diagrams each showing a cross section of a portion of a stent frame 102 of one embodiment of a heart valve prosthesis 100 of the present invention, showing leaflets 121 / leaflet flaps 122 partially guided through openings 135 of skirt flaps 132 covering commissure cells 117 in the most distal row 114 of the stent frame 102. In Fig. 5, 138 denotes a strut of the most distal commissure cell in the cross section.

[0116] Figure 5A An embodiment is shown in which a first portion 133 of the skirt flap 132 covers the stent frame 102 at the lumen and a second portion 134 of the skirt flap 132 covers the stent frame 102 outside the lumen. The skirt flap 132 is not guided or wrapped around the struts 138 of the commissure unit. In this embodiment, the skirt body 131 is also attached to the lumen side 104 of the stent frame 102.

[0117] Figure 5B Another embodiment for attaching the skirt element and for forming the decoupling element 99 is shown. Here, the first portion 133 of the skirt flap 132 (and as a result: also the body 131 of the skirt 130, which, however, is not shown in FIG. 5 ) is attached to the luminal side 105 of the stent frame 102, and the second portion 134 of the skirt flap 132 is wrapped around the struts 138 of the commissure unit. An opening 135 is formed on the luminal side 104 of the stent frame 102, for example, by not connecting the two ends of the second portion 134 of the skirt flap 132 on the luminal side 104.

[0118] Figure 5C Yet another embodiment for attaching skirt elements and for forming decoupling element 99 is shown. Here, skirt body 131 is attached from the luminal side 104 of the stent frame, and first portion 133 of skirt flap 132 is also attached to the luminal side 104 and includes opening 135. Opening 135 is located within commissure unit 117. Second portion 134 of skirt flap 132 is wrapped around struts 138 of the commissure unit so that the second portion is attached to the stent frame 102 extraluminally and covers opening 135 extraluminally. Ends 134a and 135b of the second portion may be stacked one on top of the other, as shown in FIG. Figure 5C as shown in .

[0119] In FIG6 , a schematic diagram of the mechanism of the decoupling element 99 is shown, with a front view (A) and a cross-section (B) through the stent frame 102. As schematically depicted, the decoupling element 99 (see above description) provides a flexible "suspension" for the leaflets in the heart valve prosthesis 100 of the present invention, represented by a representative spring element 90. In the embodiment shown in FIG4 , the decoupling element is achieved by attachment of the leaflets via the skirt 132 covering the commissure unit 117. Thus, in this embodiment, the skirt (or rather the skirt portion) covering the commissure unit 117 achieves the suspension of the spring element for the commissure. In this way, as discussed above, the leaflets are decoupled from the stent frame 102 and the movement of the stent frame 102, achieving a flexible commissure, and thus the valve element has a higher flexibility than if it were directly attached to the stent frame / its struts.

[0120] Figure 7 A diagram showing an assembled embodiment of the heart valve of the present invention. Figure 7 In FIG. 1 , it can be seen that the valve element 120 is Figure 7 In the embodiment shown, there are three leaflets 121. The valve element 120 is attached to the lumen 103 of the stent frame 102. The skirt 130 is attached to the lumen 103 of the stent frame 120 together with the skirt body 131, luminally covering the most proximal row 110 as well as the first and second intermediate rows 111a, 111b. The separation cells 118 of the cells of the most distal row 114 are not covered, while the commissure cells 117 of the most distal row 114 are covered from the lumen side 103 by the first portion 133 of the skirt flap 132 and are covered from the outside by the second skirt 134 folded over the most distal edge of the commissure cells 117. The skirt is sutured to the stent frame using sutures to attach it to the struts of the cells forming the stent frame. In the case where the cells of the most distal row 114 and the cells in the intermediate row 112 directly adjacent to the most distal row 114 are not covered, sufficient space is provided for erosion.

Claims

1. A heart valve prosthesis (100) for implantation into a patient's heart, wherein the heart valve prosthesis (100) comprises: - a stent framework (102) comprising a lumen (103), a lumen side and an abluminal side (104; 105) and a plurality of cells (110; 111; 112; 114) arranged in circumferential rows, wherein the plurality of cells comprises at least a proximal row of cells (110), at least one intermediate row of cells (112) and a distal row of cells (114); - a valve element (120) which is mounted to the heart valve prosthesis (100) and comprises at least two, preferably three leaflets (121); - a skirt (130) attached to the stent frame (102), wherein the skirt (130) comprises a skirt body (131) and at least two, preferably three skirt flaps (132) integral with or attached to the skirt body (131), wherein the skirt body (131) covers at least the nearest row of cells (110), and wherein each skirt flap (132) covers a corresponding coupling cell (117) in the farthest row of cells (114), thereby forming a decoupling element (99); and The leaflets (121) are mounted to the heart valve prosthesis (100) within the commissure unit (117) in the most distal unit (114) via corresponding decoupling elements (99).

2. The heart valve prosthesis of claim 1, wherein each skirt flap (132) comprises an opening (135), such that the opening (135) is located within the commissure unit (117) respectively covered by each skirt flap (132).

3. A heart valve prosthesis as described in any one of claims 1 or 2, wherein each skirt flap (132) includes a first part (133) and a second part (134), the first part (133) including an opening (135) located within the at least one commissure unit (117), and the second part (134) is designed to fold over the farthest edge (116) of the commissure unit (117) so that the second part (134) is attached to the stent frame (102) extraluminally, thereby at least partially covering the opening (135).

4. A heart valve prosthesis as described in any one of claims 1 to 3, wherein the skirt body (131) is attached to the luminal side (104) of the stent frame (102), and each skirt flap (132) includes a first part (133) and a second part (134), wherein the first part (133) is attached to the outside of the luminal side (105), and wherein the second part (134) is designed to be folded around the side support (138) of the connection unit (117) from the outside of the luminal side (105) of the stent frame, so that the second part (134) is luminally attached to the stent frame (102), thereby forming an opening (135) on the luminal side (104).

5. A heart valve prosthesis as described in any one of claims 1 to 3, wherein each skirt flap (132) includes a first part (133) and a second part (134), the first part (133) being attached to the luminal side (104) and including an opening (135), the opening (135) being located within the at least one commissure unit (117), and the second part (134) being designed to be folded from the luminal side (104) of the stent frame (102) around a side support (138) of the commissure unit (117) so that the second part (134) is attached to the stent frame (102) extraluminally, thereby at least partially covering the opening (135).

6. A heart valve prosthesis as claimed in any one of the preceding claims, wherein each leaflet (121) comprises a leaflet body (123) and a leaflet flap (122), the leaflet body (123) being arranged in the lumen of the stent frame (102), and the leaflet flap (122) being guided from the lumen side of the stent frame (102) to the outside (105) of the lumen through an opening (135) located in the connection unit (117) covered by a skirt flap (132), for fixing each leaflet (121) to the stent frame (102) through the decoupling element.

7. A heart valve prosthesis according to any of the preceding claims, wherein the farthest row unit (114) comprises at least two, preferably three connection units (117) separated from each other by separation units (118), wherein the connection units (117) are longer than the separation units (118) and therefore protrude in the distal direction D.

8. The heart valve prosthesis of claim 7, wherein the commissure units (117) have a substantially rhombic shape, and optionally, wherein the separation units (118) have a substantially triangular shape.

9. The heart valve prosthesis of any of the preceding claims, wherein the proximal row of cells (110) comprises cells (119) having a substantially heart-shaped shape.

10. The heart valve prosthesis of any of the preceding claims, wherein the stent frame comprises an intermediate row (112) directly adjacent to the most distal row (114), preferably the intermediate row (112) comprising cells having a substantially triangular shape.

11. A heart valve prosthesis as claimed in any of the preceding claims, wherein the stent frame comprises a first intermediate row (111a) directly adjacent to the nearest row (110), preferably wherein the first intermediate row (111a) comprises cells having a substantially hexagonal shape, and preferably wherein the stent frame comprises a second intermediate row (111b) directly adjacent to the first intermediate row (111a), preferably wherein the second intermediate row (111b) comprises cells having a substantially hexagonal shape.

12. The heart valve prosthesis according to any of the preceding claims, wherein the skirt (130) comprises a fabric, membrane or tissue material having a defined flexibility, and preferably comprises a material selected from polyester, polyurethane, PTFE.

13. A heart valve prosthesis as claimed in any of the preceding claims, wherein a skirt body (131) of a skirt (130) is arranged on the lumen side (104) of the stent frame (102), a corresponding first portion (133) of the skirt flap (132) is arranged on the lumen side (104) of the stent frame (102), and a second portion (133) of the skirt flap (132) is arranged on the lumen outer side (105) of the stent frame (102).

14. The heart valve prosthesis of any of the preceding claims, wherein the stent frame (102) is balloon expandable or self-expanding.

15. A method for manufacturing a heart valve prosthesis (100), the method comprising the following steps: - providing a stent framework, the stent framework comprising a lumen, a lumen side and a lumen side, and a plurality of cells arranged in circumferential rows, wherein the plurality of cells comprises at least a proximal row of cells, a middle row of cells and a distal row of cells; - attaching, preferably suturing, a skirt to the stent frame, wherein the skirt comprises a skirt body and at least two, preferably three, skirt flaps integral with the skirt body, such that the skirt body covers at least the most proximal row of cells on the luminal side of the stent frame, and each skirt flap has a respective first portion and a second portion, the first portion comprising an opening, covering cells in the most distal row of cells on the luminal side of the stent frame, and the second portion extending along the most distal edge of the covered cells; - attaching at least two, preferably three leaflets to the stent frame, wherein each leaflet comprises a leaflet body and a leaflet flap, the leaflet body being disposed within the lumen of the stent frame and the leaflet flap being guided from the lumen side of the stent frame to the outside of the lumen through the opening of the first portion of the skirt flap; - folding the respective second portion of the flap over the outermost edge of the covered unit so as to at least partially cover the leaflet and the opening with the second portion; - Attaching a second skirt portion to the stent frame, thereby securing the leaflet to the stent frame via a decoupling element.

16. The method of claim 15, wherein each leaflet comprises two petals which are guided through the opening in a folded state and which unfold after passing through the opening and are subsequently covered by the second portion of the skirt.

17. The method of claim 15 or 16, wherein a heart valve prosthesis according to any one of claims 1 to 14 is manufactured.

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