Method for manufacturing a heart valve prosthesis and its components

Abstract

A heart valve prosthesis implanted by catheter surgery, comprising an expandable central body (16, 116), a housing (18) having one or more auxiliary components (22), and at least one connection block (20, 120) for connecting each auxiliary component of the housing (18) to the central body (16, 116), each connection block being provided with a mechanical coupling mechanism (38, 138 and 40, 140) for the expandable central body (16).

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a heart valve prosthesis and components thereof.

[0002] The present invention has been developed in particular, but not exclusively, with respect to a valvular prosthesis intended to replace the physiological function of an incompetent heart valve, in particular, but not exclusively, a cardiac prosthesis for an atrioventricular heart valve, which has been specially developed for use by a transcatheter implantation procedure. [Background technology]

[0003] Heart valves are complex and delicate components that regulate the correct functioning of the human heart. Their main purpose is to allow one-way blood flow within the heart chambers, both during the filling phase (diastole) and the emptying phase (systole).

[0004] To optimize the efficiency of pumping blood, the heart is divided into two distinct compartments, the right and left compartments, each of which is divided into two chambers, the atrium and the ventricle. The right compartment of the heart, consisting of the right atrium and right ventricle, returns blood from the peripheral circulation and sends it to the pulmonary circulation for oxygenation. The left compartment, similarly divided into the left atrium and left ventricle, supplies blood to the peripheral circulation and returns oxygenated blood from the pulmonary circulation to the systemic circulation.

[0005] To ensure that blood flows in one direction within the heart, valves are located at the outlet of each ventricle and atrium. The valves located at the outlet of the atria are called atrioventricular valves, as they connect the atria and ventricles on each side of the heart. On the right side of the heart, this valve is also called the tricuspid valve, while on the left side it is usually called the mitral valve. Finally, the valve located at the outlet of the right ventricle is called the pulmonary valve, and the valve at the outlet of the left ventricle is called the aortic valve.

[0006] Conditions that alter the function of the heart valves are among the most serious in the cardiovascular field. Among them, mitral valve insufficiency, or the inability of the mitral valve to close completely, is a very debilitating valvular condition because it reduces the efficiency of the pumping action of the left side of the heart, which is responsible for circulating blood throughout the body.

[0007] With the current state of the art, the standard of care to treat severe valve insufficiency is to replace the valve with an implanted prosthesis. In other cases, mainly in the case of mitral valve insufficiency, valve repair is performed. In both cases, an open-heart surgery is performed that allows direct access to the insufficient valve. This operation requires the heart to be temporarily stopped and an artificial extracorporeal blood circulation to be generated using an appropriate pump and oxygen exchanger. Despite improvements in the techniques for managing cardiac arrest and improvements in extracorporeal circulation systems, open-heart treatments carry risks due to their invasiveness and the duration of the operation. In fact, both repair and replacement implanted prostheses typically used in conventional surgery usually require lengthy operations to be fixed at the implant site using specific suturing techniques. In some cases, the patient's overall condition, such as their advanced age or coexisting medical conditions, makes surgical treatment impossible.

[0008] To overcome these limitations, minimally invasive interventional procedures have been developed recently, the so-called transcatheter procedures. For this purpose, a radially foldable prosthesis is used that can self-fixate at the implantation site. This prosthesis can be implanted by a catheter that can be moved in the vasculature to reach the implantation site from a remote access made in a peripheral vessel, for example a vein or the femoral artery, and release the cardiac prosthesis. This allows the correction of valve insufficiency with limited use of surgery, while the heart is still beating. Currently, transcatheter techniques are only used clinically for the treatment of the aortic valve.

[0009] The situation is different when it comes to the treatment of atrioventricular valve dysfunction, and in particular mitral regurgitation: the complex anatomical configuration of the valve and its surrounding structures, the variety of pathologies that differ significantly from each other and that directly or indirectly affect the valve, make it extremely difficult to meet the requirements for a safe and effective implantation into the mitral valve via a transcatheter route.

[0010] In recent years, numerous transcatheter prostheses for atrioventricular valves have been developed, which can be implanted according to different accesses and procedures. The first implantation method, especially adapted for the mitral valve, creates an access to the native valve to be replaced via the apex of the left ventricle, a method already developed by the same applicant (WO2014 / 080338 and WO2014 / 080339). In this procedure, a chest incision is made to expose the apex of the left ventricle. Via the apex, direct access to the ventricle is surgically obtained, possibly by temporarily placing an apical port, i.e. limited to the duration of the procedure. Via the apical access, the catheters necessary to carry out the implantation procedure are then inserted at any time.

[0011] In another methodology developed by the same applicant (WO2021 / 014400), transseptal access is provided instead. The term "transseptal access" is intended to be understood as an access to the atrioventricular valve to be replaced, starting from the peripheral femoral vein and ascending up the inferior vena cava to the right atrium. In case of implantation in the mitral position, it is also necessary to reach the left atrium through an opening created in the septum between the two atria in an interventional procedure. The left atrium allows antegrade access to the native mitral valve. In this way, damage to the left ventricle, i.e. perforation, associated with a transapical procedure allowing access to the mitral valve from the ventricular side, i.e. retrogradely, is prevented.

[0012] Valve prostheses implanted via the transcatheter route have been specially studied so that they can assume a configuration of minimal radial dimensions, so that they can be inserted into a catheter for navigation within the patient's cardiovascular system. Patent application WO2015 / 118464 by the same applicant describes, for example, a transcatheter prosthesis particularly suitable for this purpose. This prosthesis has a support and interface structure with the native valve and a group of flexible prosthetic leaflets fixed therein. The prosthesis structure consists in particular of a central body of valve action, a receiving section formed by two or more arcuate segments, and a connecting block attached to the end of a connecting arm fixedly connected to the structure of the central body, providing mechanical continuity between the central body and the arcuate segments.

[0013] In patent application WO2015 / 118464, the connection block appears to be fixed to the connection arm by welding or soldering. In fact, it is technically complex and uneconomical to construct a connection block, particularly of a design that meets the requirements imposed on the prosthesis described in patent application WO2015 / 118464, integrally with the connection arm of the central body structure. In fact, it should be noted that the structural parts of this type of prosthesis are usually constructed by laser cutting from tubes of superelastic alloys (for example Nitinol), and this technology does not allow the central body and the connection block to be constructed integrally.

[0014] However, the applicant points out that known prostheses have problems with the durability of the welded connections between the connecting block and the flexible arms due to the in vivo surgical conditions, in particular the cardiac cycle, which places significant cyclical loads on their components. At the same time, the consequences of structural failure in vivo are clearly catastrophic, since separation of the connecting block from the connecting arms of an implanted prosthesis can lead to dislodging or migration of the prosthesis with potentially serious adverse effects on the patient. Summary of the Invention

[0015] One of the objectives of the present invention is to solve the problems of the prior art. In particular, it is intended to provide a heart valve prosthesis that is foldable and durable. Another objective is to provide a heart valve prosthesis that minimizes the risk of separation between the connection block and the central body both during implantation and during use, making it particularly safe over time and even under large fatigue loads. Another objective is to provide a device that is economical and easy to manufacture.

[0016] To achieve these and other objects, the present application relates to a prosthesis according to the appended claims.

[0017] In particular, a transcatheter implantable heart valve prosthesis is described that includes an expandable central body, a housing having one or more auxiliary components, and at least one connection block for connecting each auxiliary component of the housing to the central body.

[0018] According to one aspect, each connection block is provided with a mechanical coupling mechanism to the central body, more particularly to a connection arm fixedly connected to the structure of the central body, said coupling mechanism being preferably of the snap-fit ​​type, said coupling mechanism being preferably reversible.

[0019] This results in a connection that is extremely stable, simple in design and construction, and without the risk of breaking even under heavy cyclic fatigue loads. Moreover, the described solution maintains the possibility of constructing the structure of the central body and the connecting arms by standard laser cutting techniques, which constitute an integration technique for this type of part. Laser cutting of a tubular base material is in fact a known and preferred process for obtaining the structure of the central body, but it does not allow to generate the shapes required for the function of the connecting blocks. It is therefore technically and economically advantageous to construct the connecting blocks separately from the structure of the central body. However, a stable and durable connection between these two parts is essential, which is achieved by the present invention.

[0020] According to one embodiment, the coupling mechanism comprises at least one housing, which is provided on the connection block, into which at least one corresponding coupling member provided on the central body is inserted. Preferably, the coupling member is provided with one or more hook teeth for connecting in a snap-fit ​​manner with the connection block. The coupling member, or the housing on the connection block, or both parts of the coupling mechanism have elastically deformable parts to enable the snap-fit ​​connection.

[0021] Furthermore, a heart valve is described in which the coupling member is a peg, which may be provided on a resilient arm extending from the structure of the central body, in particular at the distal end of the resilient arm, which may be constructed integrally with the structure of the central body, preferably the peg is also constructed integrally with the central body, for example by laser cutting.

[0022] According to one embodiment, a prosthesis is described that includes two or more auxiliary parts forming a receiving part and two or more corresponding connection blocks between the receiving part and the central body. In this configuration, a particularly advantageous variant can be used in which at least one echo-opaque or radio-opaque marker is provided on one of the connection blocks. This marker clearly identifies the orientation of the prosthesis and also provides an indication on the direction of the angular rotation to be imposed on the implant catheter for a potential correction on the orientation of the prosthesis. In this way, another assistance is provided to the operator implanting the prosthesis, i.e. by operating with a transcatheter technique, the operator can view the prosthesis only by echo- or radio-examination during the positioning of the prosthesis. The limitations of these imaging methods, combined with the substantial symmetry of the configuration of the prosthesis, are particularly advantageous in order to have a clear reference for identifying the orientation of the prosthesis. The placement of a marker on one of the connection blocks solves this problem.

[0023] According to another aspect, a prosthesis is described in which the connecting arms are joined at the end regions in pairs, with each pair being provided with a single joining mechanism.

[0024] According to another aspect, a prosthesis is described with a connection block that can be fully described as the intersection of two planar profiles projected at 90° to each other. This feature makes the connection block compatible with high-quality and economically advantageous working techniques and at the same time capable of fulfilling all the functional and structural requirements related to the above-mentioned transcatheter valve prosthesis. In particular, its construction is made possible by a wire EDM process, which guarantees high dimensional accuracy, optimal quality of the surface and convenience in terms of manufacturing costs compared to parts assembled by conventional machining operations (e.g. machining with chip removal) or welding.

[0025] Further, a method for constructing a connection block for connecting an auxiliary part of a receiving part to a central body of a heart valve prosthesis to be implanted in a transcatheter procedure is described. The method comprises the steps of providing a material slab. The method comprises the steps of performing a first profiling, preferably by wire EDM, along a first cutting path to obtain a semi-finished product. The method comprises the steps of rotating the semi-finished product through a predetermined angle. Preferably, the angle is 90°. The method comprises the steps of performing a second profiling, preferably by wire EDM, along a second cutting path to obtain a connection block. [Brief description of the drawings]

[0026] Further characteristics and advantages will become apparent from the following detailed description of preferred embodiments of the invention, given purely by way of non-limiting example with reference to the accompanying drawings, in which: FIG. 1 is a schematic exploded view of the structural components of a heart valve prosthesis according to the invention; FIG. 2 shows the central body and the connecting block of the heart valve prosthesis of FIG. 1 assembled together; FIG. 3 is a perspective view of a connection block between the central body and the receiving part, which is connected to the auxiliary part of the receiving part; FIG. 4 is a front view of the connection block of FIG. 3 connected to the central body; FIG. 5 shows a central body according to a second embodiment, 6a and 6b are different perspective views of the connection mechanism between a connection block according to a second embodiment and the central body shown in FIG. 5; 7a to 7d show a procedure for assembling the connection block to the coupling mechanism according to the second embodiment shown in FIGS. 5 and 6; · Figures 8a to 8f show the steps of constructing a connection block according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Referring now to the drawings, FIG. 1 shows an implantable cardiac prosthesis 10 used to replace the function of the atrioventricular valves.

[0028] The prosthesis 10 may, in particular, ·Central body 16, - Storage compartment 18, A connection block 20 connecting the central body 16 and the receiving part 18; A group of flexible prosthetic valves, not shown, fixed inside the central body It consists of:

[0029] The prosthesis 10, as well as each of its constituent parts, is configured to be foldable without adversely affecting the safety and functionality of the prosthesis itself. Thus, the overall radial dimensions of the central body 16 and the housing 18 can be temporarily reduced to allow introduction into the heart cavity through an access with a small opening compatible with minimally invasive surgical techniques, with transcatheter techniques for positioning and implanting the cardiac prosthesis. In other words, the cardiac prosthesis can be inserted through a catheter with a low radial profile that can carry the prosthesis through the patient's cardiovascular system to the interior of the heart cavity, i.e., to the implantation site, where it can be deployed and implanted to functionally replace the native valve.

[0030] More specifically, the central body 16 is the part of the prosthesis 10 that delimits a conduit for blood to pass through the device. A flexible prosthetic valve that allows unidirectional flow of blood in the conduit is fixed in the central body 16, as known for example from Italian patent no. 20140204 by the same applicant.

[0031] The central body 16 is a radially collapsible elastic structure which, as a result of springback, tends to expand to a diameter greater than the maximum diameter that maintains the joint, i.e. contact, between the free ends of the closed prosthesis. The central body is provided with connecting arms 19 to which connecting blocks 20 are fixed, as shown in FIG. 2.

[0032] The receiving portion 18 is the portion of the prosthesis 10 that resists and limits the free expansion of the central body 16, preventing it from exceeding a maximum diameter compatible with maintaining the coaptation between the prosthetic valves. The receiving portion 18 has a substantially annular shape and is longitudinally inextensible, i.e., its peripheral expansion is not significantly altered even if the central body 16 is internally expanded by the application of an outward radial force.

[0033] The receiving part 18 is preferably divided into two mutually separated and substantially arcuate sub-parts 22, which for the sake of brevity will be referred to below by the term "arc". Each arc 22 can be selectively coupled to a connection block 20 and is fixedly coupled to the connection block 20 in the final implanted configuration. Although only one of the two connection blocks 20 is shown in the figures, the embodiment described here comprises two connection blocks 20 arranged symmetrically with respect to each other, one of which is hidden by the illustrated connection block 20.

[0034] Each arc 22 has two ends 24, each of which is provided with a coupling 26. The connecting block 20 is provided with a pin 28 which can be connected to the coupling 26. The pins 28 are connected to each other by a rigid, inelastic transverse structure 31, the function of which is to rigidly connect the ends 24 of the arcs 22 and to prevent the two ends 24 of two successive arcs from moving away from each other in the assembled state of the prosthesis, so that the inelasticity of the entire receiving part 18 is not compromised.

[0035] Now, referring to FIG. 3, in a preferred embodiment, the pin 28 is provided with a slot 29 on the side. The coupling 26 at the end 24 of the arc 22 is substantially tubular and has an axial hole 27 suitable for receiving the pin 28. The coupling 26 is further provided with a cutout in the tubular structure, which defines a tongue 30. The tongue 30 is formed so as to extend towards the inside of the tubular structure and interferes with the slot 29 when the pin 28 is inserted into the axial hole 27. In fact, the end 32 of the tongue 30 abuts against the slot 29 formed in the pin 28, preventing the inserted pin 28 from being pulled out. This prevents the arcs 22 from accidentally separating from each other and from the connection block 20, ensuring the stability of the prosthesis and ensuring the safety of the patient. For the sake of clarity, the figures show only one coupling 26 of the arc 22 fixed to the respective pin 28 of the connection block 20. It will be appreciated that in use, all of the arcs 22 are secured at their respective ends to pins in the connection block 20 .

[0036] In use, after connection of the arc 22 with the connection block 20 , the leaflets of the native valve remain trapped within the bond between the central body 16 and the housing 18 .

[0037] Referring now to the details of FIG. 4, the connecting block 20 provides a coupling mechanism to the expandable central body 16 .

[0038] This is in particular a coupling mechanism of the snap-fit ​​type, which in fact comprises two housings 38 provided on each connecting block 20 for corresponding pegs 40 provided on the central body, in particular on the ends of the connecting arms 19. The pegs are provided with hook teeth 42 for snapping into edges 43 formed on the corresponding housings 38 of the connecting blocks 20.

[0039] The peg 40 is further provided with a stop surface 44 adapted to abut the connecting block 20, specifically abutting a lower surface 46 thereof. In this manner, once the peg is inserted into the housing 38, it is locked in place and remains fixedly attached to the connecting block 20, i.e., the hook teeth 42 prevent the peg from being pulled out and the stop surface 44 prevents the peg from advancing further within the housing 38.

[0040] 4, the housing 38 is an elongated throughway that extends in a direction substantially parallel to the direction of extension of the pins 28 of the connecting block 20. When the connecting block 20 is connected to the arm 19, the pins 28 and the pegs 40 are preferably disposed in the same plane.

[0041] Housing 38 preferably has lateral openings 48 to facilitate blood cleaning of the interior of housing 38 .

[0042] As can be seen in the figures, in the embodiment described, each connection block 20 is provided with two housings 38, each adapted to receive a peg 40. The arms 19 in the embodiment shown are paired in two sets, each with a peg 40. Although an embodiment in which a connection block 20 is provided with one arm 19, one peg 40 and one housing 38 should not be excluded, the use of at least two pegs and respective housings increases the torsional stability of the attached structure, which is particularly appreciated during its use, in particular during the connection of the connection block 20 with the arc 22, which is carried out during the operation to implant the prosthesis directly into the ventricle of the patient's heart.

[0043] The pegs 40, as previously mentioned, are preferably arranged at the ends of the arms 19 and may be arranged integrally with the central body 16. In particular, it is possible to construct the entire assembly formed by the central body, the arms 19 and the pegs 40 by laser cutting directly from a tube of a material exhibiting superelastic behaviour, such as Nitinol.

[0044] In the embodiment shown in FIG. 4, the portion of the peg 40 arranged in the housing 38 features two cross sections of different dimensions. The cross section of the stop surface 44 has dimensions very similar to the cross section of the housing 38 in order to ensure the stability of the connection and therefore of the joint between the connection block 20 and the arm 19. Instead, the cross section of the peg 40 in the vicinity of the hook tooth 42 is reduced in dimensions relative to the cross section of the housing 38, especially in the direction in which the hook tooth 42 is pointing, in order to allow the end of the peg to bend during the introduction of the hook tooth 42 and its engagement with the edge 43 of the housing itself. Naturally, the cross section of the hook tooth 42 is adapted for insertion through the housing 38.

[0045] The portion of the peg 40 proximate the hook tooth 42 may also be pre-curved to resist the deformation required to couple the hook tooth 42, making the coupling operation more stable as the peg 40 itself acts as a preloaded resilient element once inserted into place.

[0046] With reference to FIG. 5, in a second embodiment of the structure of the central body 116 of the prosthesis, the connecting arms 119, which grip the same connecting block 120, are joined to each other at their respective ends at the joint 121. The joining mechanism comprises a pair of consecutive pegs 140, which are arranged in the middle of the joint 121 between the two connecting arms 119. Both pegs have hook teeth 142 at their ends, which point in opposite directions. In the illustrated version, the pegs can have a configuration characterized by a predetermined camber 145 oriented according to the orientation of the hook teeth 142. As a result, the pegs 140 diverge away from each other. In this way, the effect of the elastic preload of the pegs makes the joining of the teeth even more stable. In any case, it is not excluded that the pegs 140 may also be straight, like the pegs 40 in the embodiment of FIGS. 1 to 4.

[0047] Figures 6a and 6b show, according to two different projections, a connecting block 120 compatible with the central body 116 described in Figure 5. In this particular embodiment, the connecting block 120 comprises a single housing 138, which is centrally located and dimensioned to accommodate both pegs 140. The coupling mechanism is thus formed by a pair of pegs 140 and the common housing 138.

[0048] The hook teeth 142 engage with an upper edge 143 of this housing 138. At this location, two plates 147 are provided on the connecting block 120, which are preferably planar and protrude from both sides of the housing 138. The plates cover the hook teeth 142 and prevent interference between them and the surrounding subvalvular structures of the atrioventricular valve (e.g. chordae tendineae). Indeed, interference could lead to damage of the anatomical structures themselves, and also to the risk that the mechanical action on the hook teeth could dislodge them from the end of the housing, resulting in an accidental separation of the connecting block from the connecting arms. The joint 121 between the two connecting arms 119 also defines a stop surface 144 that abuts against a lower surface 146 of the connecting block when the connecting block is coupled with the connecting arms. The interference between the hook teeth 142 and the upper edge 143, combined with the abutment between the stop surface 144 and the lower surface 146 of the connecting block, stabilizes the connecting block axially.

[0049] Figures 7a to 7d show the procedure for coupling the connection block 120 and the connection arm 119 according to the structural solution described in Figure 6a. Figure 7a shows the coupling mechanism in a configuration in which the pegs 140 are not deformed. From this configuration, the pegs 140 are elastically deformed until the rear parts of the hook teeth 142 come into contact with each other in order to move together (Figure 7b). In this configuration, the entire front part of the hook teeth 142 has a smaller spatial requirement than the cross section of the housing 138 present on the connection block 120. In this way, as shown in Figure 7c, the peg 140 can be introduced into the housing 138 and slide therein. When the peg 140 is fully inserted into the housing 138 of the connection block 120 and the lower surface 146 of the connection block comes into contact with the joint 121 between the connection arms, in particular the stop surface 144, the hook teeth 142 are separated from each other by the springback of the pegs 140 and come into engagement with the upper edge 143 of the housing 138, as shown in Figure 7d.

[0050] In this way, the connection block 120 is fixedly joined to the connection arm 119. The design of the connection block may also provide additional extension pieces, such as two flat plates 149, which protrude from the underside of the connection block and engage the joint 121 between the two connection arms to increase the stability of the connection block against lateral or torsional loads.

[0051] The connection block 120 has pins 128 similar to the pins 28 described in the first embodiment. The pins 128 allow for connection of the arc 22 to the coupling 26.

[0052] 8a to 8f show, by way of non-limiting example, the construction process of the connection block 120, which requires only two machining steps by wire EDM, a technique that allows mass production at low cost and guarantees a high level of dimensional accuracy and a high quality surface finish. Figures 8a and 8b show the first step of the machining operation, where, as seen in Figure 8a, a first wire cutting pass 200 performed on a slab 202 of the metal material selected for the connection block 120 allows the construction of a prismatic semi-finished product 204, shown in Figure 8c, which, when viewed from the A direction, already has the same profile as the final part. By rotating the prismatic semi-finished product 204 by 90° according to the perspective shown in Figure 8d, the second step of the machining operation can be performed, where a second cutting pass is performed along the profile 206 shown in Figure 8e. This final profile allows the final shape of the connection block 120 to be obtained without the need for additional subsequent machining operations, as shown in Figure 8f.

[0053] It should be noted that the above manufacturing method is possible as a result of the particular design of the connecting block 120, which can be perfectly described as the intersection of two planar profiles projecting at a precise angle to each other.

[0054] A further advantage of the above-mentioned embodiment of the invention is the reversibility of the coupling mechanism between the connection block 20,120 and the connection arm 19,119. In fact, by means of a suitable mechanical tool, the hook teeth 42,142 can be disengaged from the edge 43,143 of the housing 38,138, which allows the pegs 40,140 to be removed from the housing itself and the connection block to be separated from the connection arm. Reversibility here is understood as the possibility of being able to detach the connection block from the connection arm during the assembly phase of the manufacturing cycle of the prosthesis or at any stage before the prosthesis is inserted into the patient's body. However, the coupling mechanism is configured to be irreversible during the insertion phase into the patient's body and in use, i.e. while the valve is implanted. The connection between the parts is indeed stable under operating conditions, and the connection block can never accidentally detach from the connection arm. An accidental detachment would in fact lead to a separation of the receiving part and the central expandable part, which could lead to a failure of the prosthesis or to its migration, with harmful consequences for the patient. In the configuration shown in the drawings, the hook teeth 42, 142 are recessed relative to the thickness of the wall that defines the upper edge 43, 143 with which they engage. Thus, the hook teeth remain protected and cannot be accidentally disengaged. It is understood that other arrangements are possible to ensure that the connection is stable. By way of example, the pegs 40, 140 can be made sufficiently rigid to prevent the pegs from bending and disengaging the coupling mechanism, taking into account the forces and stresses that occur during insertion into the patient's body and during use. Alternatively, a locking device can be provided to prevent release of the coupling mechanism.

[0055] According to a variant not shown, one of the connection blocks 20, 120 can be provided with a radiopaque or echopaque marker that can be identified with absolute certainty by the imaging equipment (echocardiography and radiography) typically used in transcatheter procedures.

[0056] In the above-described embodiments, in the configuration of the prosthesis in FIG. 1, there is always reference to the presence of two connection blocks, equal to the number of auxiliary parts 22 of the receiving part. Naturally, the prosthesis may comprise a different number of auxiliary parts 22 of the receiving part. The described version is the preferred version, since the presence of two auxiliary parts 22 allows the use of two guide wires, which are easier to position correctly than one guide wire that may remain entangled in the chordae tendineae, as described in patent application WO2021 / 014400. However, the possibility of the receiving part being composed of one auxiliary part, i.e. formed like a cut ring, should not be excluded. In this case, one connection block is provided.

[0057] Finally, in the case of prostheses primarily intended for the replacement of the tricuspid valve, solutions with a third auxiliary part should not be excluded, even though this requires a higher complexity of the positioning operations.If more than two auxiliary parts, i.e. more than two connecting blocks, are provided, it is particularly advantageous to provide two of the three connecting blocks with radiopaque or echopaque markers, which may differ from each other.

[0058] Furthermore, it should be emphasized that the above-described coupling mechanism between the central body 16, 116 and the connection block 20, 120, formed by the housing 38, 138 and the pegs 40, 140, can also be used with connection blocks having a different coupling system to the arc 22. Similarly, the above-described pin / hole coupling mechanism between the arc 22 and the pin 28, 128 can also be used with connection blocks 20, 120 having a different coupling system to the central body 16, 116.

[0059] Naturally, the principles of the invention remain the same and the details of the form and construction of the embodiments may vary widely with respect to that described and illustrated without departing from the scope of the invention.

Claims

1. 1. A cardiac valve prosthesis for transcatheter implantation, comprising: an expandable central body (16, 116); a housing (18) having one or more auxiliary components (22); and at least one connection block (20, 120) separate from the central body (16, 116) for connecting each auxiliary component of the housing (18) to the central body (16, 116), each connection block being provided with a mechanical coupling mechanism (38, 138 and 40, 140) for coupling the connection block to the expandable central body (16).

2. 10. The heart valve prosthesis of claim 1, wherein the coupling mechanism is of the snap-fit ​​type.

3. 3. The heart valve prosthesis of claim 2, wherein the coupling mechanism comprises at least one housing (38, 138) mounted on the connection block (20, 120), into which at least one corresponding coupling member (40, 140) mounted on the central body (16, 116) is inserted, the coupling member (40, 140) having hook teeth (42, 142) for snap-fit ​​coupling with the connection block.

4. 2. The heart valve prosthesis of claim 1, wherein the coupling mechanism is provided with an abutment element (44, 144) arranged to abut against the connection block (20, 120).

5. 5. A heart valve prosthesis as claimed in claim 3 or 4, wherein the connecting block comprises two pins (28, 128) engageable with corresponding holes (27) provided in the auxiliary part (22) of the receiving part (18), and at least one of the housings (38, 138) is elongated in a direction substantially parallel to the axis of the pins.

6. 3. The heart valve prosthesis of claim 2, wherein the coupling members (40, 140) are pegs provided at the distal ends of resilient arms (19) integral with the central body (16).

7. 2. A heart valve prosthesis according to claim 1, wherein there are two connecting blocks (20), one of which is provided with a radiopaque or echopaque marker.

8. 2. The heart valve prosthesis of claim 1, wherein at least one of the connecting blocks (20) comprises two pins (28) engageable with corresponding holes (27) in at least one of the auxiliary parts (22) of the receiving part (18), and a transverse structure connecting these pins (28), each of which has a slot (29) that allows at least one of the auxiliary parts of the receiving part to engage in a snap-fit ​​manner.

9. 1. A method for constructing a connecting block (120) for connecting an auxiliary component of a receiving part (18) to a central body (16, 116) of a cardiac valve prosthesis to be implanted by transcatheter surgery, comprising: Providing a slab of material (202); - making a first cut along a first cutting path (200), preferably by wire EDM, to obtain a blank (204); - rotating the semi-finished product through a predetermined angle; making a second cut, preferably by wire EDM, along a second cutting path (206) to obtain said connection block (120); Methods including:

10. 1. A method for manufacturing a cardiac valve prosthesis to be implanted by catheter surgery, comprising an expandable central body (16, 116), a housing (18) having one or more auxiliary components (22), and at least one connection block (20, 120) for connecting each auxiliary component of the housing (18) to the central body (16, 116), comprising: - constructing a connection block (120) according to the method of claim 9, - connecting said connection block (120) to said central body (16, 116) A method comprising:

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