Device and assembly process for implanting a heart valve prosthesis

Abstract

A device for implanting a cardiac prosthesis, comprising a central body (16) and a containing portion (18) having one or more subassemblies (22); comprising release means for the central body, which are insertable into a catheter; and means for assisting the operation of connecting between the central body (16) and the subassemblies of the containing portion (18), comprising a catheter assembly in which each subassembly of the containing portion has at least two catheters, which are connected to each other on a portion thereof and have at least one free end for each catheter.

Description

TECHNICAL FIELD

[0001] The present invention relates to a device and assembly procedure for implanting a heart valve prosthesis.

[0002] Although in a non-limiting manner, the present invention has been developed with particular reference to a device for use in the procedure of implanting a heart prosthesis for replacing the physiological function of a dysfunctional heart valve, in particular for an atrio-ventricular heart valve. BACKGROUND

[0003] Heart valves are complex and delicate organs that control the normal function of the human heart. Their main purpose is to allow the blood to flow unidirectionally within the heart cavities, which is essential both during the filling phase of the cavities (i.e. diastole) and during the blood ejection phase (i.e. systole).

[0004] In order to optimize the efficiency of the blood pumping action, the heart is structured in two distinct compartments, each being a right compartment and a left compartment, each of which is in turn subdivided into two chambers, respectively atrium and ventricle. The right compartment of the heart, consisting of the right atrium and the right ventricle, returns the blood from the peripheral circulation and directs it to the pulmonary circulation for its oxygenation. The left compartment, in turn subdivided into left atrium and left ventricle, supplies the peripheral vessels, returning the oxygenated blood from the pulmonary circulation and pumping it into the systemic circulation.

[0005] In order to allow the blood to flow unidirectionally within the heart, valves are provided at the outlet of each chamber. Valves located at the outlet of the atrium are atrio-ventricular valves, as they connect the atrium chamber to the ventricle chamber on each side of the heart. On the right side of the heart, this valve is also known as tricuspid valve, while on the left side it is commonly known as mitral valve. Finally, the valve located at the outlet of the right ventricle is known as pulmonary valve, while the valve located at the outlet of the left ventricle is known as aortic valve.

[0006] The pathologies that affect the function of the heart valves are among the most serious in the cardiovascular field. Among these, the insufficiency of the mitral valve, i.e. the inability to close completely, is a highly impairing valve pathology, as it reduces the efficiency of the pumping action of the left side of the heart, which is responsible for the circulation of blood throughout the body.

[0007] In the current state of the art, the standard therapy for the treatment of severe valvular dysfunctions is the replacement of the valve with an implantable prosthesis. In other cases, mainly in the case of mitral valve dysfunctions, there are regulations for their repair. In both cases, it is provided through a direct vision surgery procedure, which allows direct access to the dysfunctional valve. This surgery requires the temporary arrest of the heart and the creation of an extracorporeal artificial blood circulation through suitable pumps and oxygenators. Despite the improvements in the techniques for managing the arrest of the heart and improving the extracorporeal circulation system, the treatment under open heart conditions is risky due to its invasiveness and duration. In fact, the implantable prostheses commonly used for repair and replacement in traditional surgical therapies usually require long surgeries to be fixed in the implantation site through specific suturing techniques. In some cases, due to the general condition of the patient, for example due to advanced age or the presence of accompanying pathologies, it is even impossible to perform surgical interventions.

[0008] To overcome these limitations, in recent years surgical interventions have been developed with reduced invasiveness, so-called trans-catheter surgeries. For this purpose, radially foldable prostheses are used, which can self-anchor at the implantation site. The prostheses can be implanted through a catheter, which is able to navigate within the vascular system and release the cardiac prosthesis reaching the implantation site through a remote access created, for example, in a peripheral vessel, such as the femoral vein or artery. Therefore, it is possible to correct valvular dysfunctions with a beating heart and limited use of surgical interventions. In the current state, trans-catheter technology is the standard of care for the treatment of aortic valves only.

[0009] The situation is different for the treatment of atrio-ventricular valve dysfunctions, in particular for the treatment of mitral valve insufficiency. The complex anatomical conformation of the valve and the surrounding structures, the variability of the pathology, which is very different from each other, directly or indirectly affecting the valve, makes it extremely difficult to meet the requirements for reliable and effective implantation in the mitral valve through the trans-catheter route.

[0010] Among the various single designs developed, the main technique developed for trans-catheter prostheses for atrio-ventricular valves provides for an apical access to the heart. This procedure requires a thoracic incision to expose the apex of the left ventricle. Subsequently, the apex is punctured in order to be able to insert an apical port. Through the apical port, the catheters necessary for the completion of the surgery are inserted in succession.

[0011] One problem of this approach is that it causes damage to the heart in a rather delicate part, such as the apex, with consequent adverse effects on the patient, such as bleeding, aneurysms, etc. SUMMARY

[0012] It is an object of the present invention to solve the problems of the prior art, in particular to provide a method for implanting a cardiac prosthesis, which is trans-catheter and does not damage the apex of the heart. It is a further object to provide a procedure which is safer for the patient. In particular, it is an object to provide a guide wire guide device and a device for implanting a cardiac prosthesis which are reliable and safe during use to allow performing such a procedure. It is a further object to provide a procedure for assembling a cardiac prosthesis using such an implantation device.

[0013] The present invention relates to a guide wire guide device and a device for implanting a cardiac prosthesis, which are particularly developed to allow a trans-catheter implantation procedure with trans-septal access as developed by the applicant. Trans-septal access is to be understood as an access to the mitral valve starting from the peripheral femoral vein, navigating in the inferior vena cava up to the right atrium and finally reaching the left atrium by using an interventional method to form a hole in the septum between the two atria. The left atrium can be antegrade into the mitral valve to be treated. In this way, the damage of the left ventricle associated with the trans-apical surgery, i.e. the perforation, which provides an access to the mitral valve from the ventricular side, i.e. retrograde, is prevented.

[0014] According to a first aspect, a guide wire guide device for positioning at least one guide wire around a heart valve is described. The device can be able to deploy a guide wire through a trans-septal access. The device can comprise a first catheter, which can be provided with at least one distal deflection system. The device can comprise a second catheter, which can be inserted inside the first catheter. The second catheter can comprise a lumen adapted to slide a guide wire therein. The second catheter can be provided with a distal deflection system for deflecting its end, preferably by an angle greater than 90°, to allow best reaching the area just below the native valve leaflets. The device can comprise a third catheter. The third catheter can be inserted inside the first catheter. The third catheter can have therein a device for capturing a guide wire. The third catheter can be provided with a distal deflection system. The deflection system of the second catheter can comprise a wire.

[0015] According to another aspect, a guide wire guide device for deploying at least two guide wires around a heart valve is described. The second catheter can comprise two lumens adapted to slide a guide wire therein. The two lumens can terminate to face substantially opposite each other.

[0016] According to an advantageous aspect, the guide wire guide device comprises a second catheter. The guide wire guide device is provided with a radiopaque and / or echogenic element. The radiopaque / echogenic element can be positioned on the distal tip of the second catheter, preferably embedded therein.

[0017] According to another aspect, the guide wire guide device can comprise a first catheter with a single lumen.

[0018] According to another aspect, a procedure for positioning at least one guidewire around a heart valve is described; the procedure can comprise the step of providing access for a first catheter through a vein, preferably the femoral vein. The first catheter can be introduced through the inferior vena cava, IVC, into the right atrium. To access the left atrium, a puncture can be made in the septum between the two atria. The procedure can comprise the steps of inserting a guidewire introducer device into the left ventricle, through the mitral valve, and deploying one or more guidewires around the native valve.

[0019] According to a preferred aspect, a procedure for positioning at least one guidewire around a heart valve is described, the procedure comprising the steps of:

[0020] - providing access for a first catheter through a vein,

[0021] - inserting the first catheter through the inferior vena cava into the right atrium and puncturing the septum between the two atria to access the left atrium,

[0022] - inserting a guidewire introducer device into the left ventricle, through the mitral valve, and positioning one or more guidewires around the native valve.

[0023] According to another aspect, a device for implanting a heart prosthesis is described. The heart prosthesis can comprise a central body and a containment portion. The containment portion can be subdivided into one or more subassemblies. The device for implanting a heart prosthesis can comprise a release device for the central body. The release device can be insertable into a catheter. The device for implanting a heart prosthesis can comprise a device for assisting the connection operation between the central body and the subassemblies of the containment portion. The device for assisting the connection operation between the central body and the subassemblies of the containment portion can comprise a catheter assembly. Each subassembly of the containment portion can have at least two catheters. The catheters can be connected to each other by a portion thereof and can each have at least one free end. The catheters can be combined together in the same sheath. The sheath can combine the catheters together along a portion thereof. The sheath can leave free at least one end for each catheter. The sheath can also comprise an additional lumen for a guidewire, preferably a central lumen. Advantageously, the catheters constituting the catheter assembly can be stably connected to each other.

[0024] According to another aspect, the device for assisting the connection operation between the central body and the subassemblies of the containment portion can comprise a catheter assembly that is incompressible in the longitudinal direction. In this way, during use, they form an incompressible contiguous passage for the guidewire. Preferably, the catheters constituting the catheter assembly can be flexible.

[0025] According to another aspect, a process for assembling a heart prosthesis is described. The heart prosthesis can comprise a central body and a containment portion. The containment portion can be subdivided into one or more subassemblies. The described process can comprise the step of inserting a guide wire into each subassembly of the containment portion. It can comprise the step of sliding the subassembly in such a way that both ends of the guide wire are outside the subassembly itself. The process can comprise the step of inserting each end of the guide wire into a respective connection element for connecting the central body and the containment portion for each subassembly of the containment portion. The process can comprise the step of inserting each end of the guide wire into a respective catheter of a catheter assembly. It can comprise the step of pulling the end of each guide wire to connect the subassembly of the central body and the containment portion.

[0026] According to another aspect, a process for implanting a heart prosthesis is also described. The heart prosthesis can comprise a central body and a containment portion subdivided into one or more subassemblies. The process can comprise the step of providing access for a first catheter through a vein. Preferably, access can be provided in the femoral vein. The process can comprise the step of inserting the first catheter through the inferior vena cava, IVC. The first catheter can be inserted into the right atrium. A puncture can be made in the septum between the two atria. Through this puncture, access can be gained to the left atrium. The process can comprise the step of providing one or more guide wires around the native valve; this operation can be performed by means of a guide wire introducer device. The subassemblies of the containment portion can be inserted. The process can comprise the step of inserting a device for implanting a heart prosthesis. The central body can then be connected to the subassemblies 22 of the containment portion 18. The in situ release of the central body can be achieved by pushing the central body out of the device for implantation.

[0027] According to another aspect, the process of implanting a heart prosthesis provides the step of inserting each subassembly into the heart by guiding each subassembly with at least one guide wire arranged around the native valve, preferably sliding each subassembly over (on) at least one guide wire.

[0028] According to another aspect, the process for implanting a heart prosthesis can provide for the use of a device for implanting a heart prosthesis, comprising means for assisting the operation of connecting the central body and the subassemblies of the containment portion, which can comprise a catheter assembly; the process can comprise the steps of inserting each end of the guide wire into a respective connection element for connecting the central body and the containment portion at its free end and inserting each end of the guide wire into a respective catheter of the catheter assembly. The process can also comprise the step of acting on the ends of the guide wire to establish a connection between the central body and the subassemblies of the containment portion.

[0029] According to another aspect, a process for implanting a heart prosthesis is described, the process comprising a central body for the prosthetic valve leaflets and a containment portion subdivided into one or more subassemblies, the process comprising the steps of:

[0030] - providing access for the first catheter through a vein,

[0031] - inserting the first catheter into the right atrium through the inferior vena cava and into the left atrium through a septal puncture,

[0032] - providing one or more guide wires around the native valve,

[0033] - inserting the sub-assembly of the containment portion,

[0034] - inserting the device for implanting a cardiac prosthesis,

[0035] - connecting the central body to the sub-assembly of the containment portion,

[0036] - pushing the central body until it is released in position.

[0037] The procedure for implanting a cardiac prosthesis is further described, wherein each sub-assembly is inserted by sliding it on one of the guide wires arranged around the native valve.

[0038] Advantageously, the procedure for implanting a cardiac prosthesis uses the device for implanting a cardiac prosthesis having all or some of the features described above; according to the procedure, after inserting the sub-assembly, for each sub-assembly of the containment portion, the following steps are performed:

[0039] - inserting each end of the guide wire into a respective connecting element for connecting the central body and the containment portion,

[0040] - inserting each end of the guide wire into a respective catheter of the catheter assembly at its free end,

[0041] - tensioning the ends of the guide wire to create a connection between the sub- assemblies of the central body and the containment portion. Preferably, access is achieved through the femoral vein. BRIEF DESCRIPTION OF DRAWINGS

[0042] The solution according to one or more embodiments of the present application, as well as the additional features and relative advantages, will be better understood with reference to the following detailed description, given by way of non-limiting example only and intended solely to be read in conjunction with the attached drawings. Figure 1 The drawings are to be read in conjunction with the detailed description, in which, for the sake of simplicity, corresponding elements are denoted with the same or similar references and their explanation is not repeated. In this regard, it can be clearly understood that the drawings are not necessarily to scale, in which some details can be exaggerated and / or simplified, and that they are solely intended to conceptually illustrate the described structures and processes, unless otherwise indicated.

[0043] In particular:

[0044] Figure 1 is a general schematic view of a cardiac prosthesis for treating a heart valve according to an embodiment of the present application.

[0045] Figure 2 showing the heart prosthesis in a disassembled state. Figure 1

[0046] Figure 3 showing a step of the process of implanting the heart prosthesis, in which a passage is provided through the atrial septum.

[0047] Figure 4 showing details of the second catheter of the guide wire guide device.

[0048] Figure 5 are different views of the same detail. Figure 4

[0049] Figure 5a showing a variant of the second catheter of the guide wire guide device.

[0050] Figure 6 showing a step of the process of implanting the heart prosthesis, in which the second catheter of the guide wire guide device is advanced in the direction of the mitral valve.

[0051] Figure 7 showing a step of the process of implanting the heart prosthesis, in which the second catheter of the guide wire guide device enters the left ventricle through the mitral valve.

[0052] Figure 8 showing a step of the process of implanting the heart prosthesis in close-up view. Figure 7

[0053] Figure 9 showing a step of the process of implanting the heart prosthesis, in which a capture device for the guide wire is positioned.

[0054] Figure 10 showing a step of the process of implanting the heart prosthesis, in which a first guide wire is positioned.

[0055] Figure 11 showing a step of the process of implanting the heart prosthesis, in which the positioning of the first guide wire is completed.

[0056] Figure 12 showing a step of the process of implanting the heart prosthesis, in which a subassembly of the containment portion of the heart prosthesis is inserted.

[0057] Figure 13 showing a step of the process of implanting the heart prosthesis, in which a device for implanting the heart prosthesis is inserted.

[0058] Figure 14 is a view of a device for assisting the connection operation between the central body and the subassembly of the containment portion.

[0059] Figure 15 is a cross section of the device. Figure 14 ​​​​

[0060] Figure 16 A step in the procedure for implanting a cardiac prosthesis is shown, wherein the central body is advanced.

[0061] Figure 17 Steps in the process of implanting a cardiac prosthesis are shown, wherein the subassemblies of the central body and the receiving portion are connected.

[0062] Figure 18 Shown are steps in the procedure of implanting a cardiac prosthesis, with the assist device removed.

[0063] Figure 19 The cardiac prosthesis is shown in a configuration ready for release in situ.

[0064] Figure 20 A cardiac prosthesis is shown ready for deployment in situ, shown within the heart.

[0065] Figure 21 The cardiac prosthesis is shown in a correctly positioned state.

[0066] Figure 22 is a cross section of a variation of the second and third catheters of a guidewire introducer device.

[0067] Figures 23 to 26 Another variation of the second and third catheters of a guidewire introducer device is shown. DETAILED DESCRIPTION

[0068] Now referring to the drawings, Figure 1 and Figure 2 An implantable cardiac prosthesis 10 for replacing the function of the atrioventricular valve is described in .

[0069] The cardiac prosthesis 10 comprises a prosthetic structure 12 for supporting the native valve and connected to the native valve and to a set of flexible prosthetic leaflets 14 fixed therein. The prosthetic structure 12 comprises, in particular:

[0070] - centrosome 16,

[0071] - a receiving portion 18,

[0072] A connecting element 20 for connecting the central body 16 and the receiving portion 18 .

[0073] The prosthesis structure 12, as regards each of its elements, is configured to be foldable without any impact on the safety and functionality of the cardiac prosthesis. It is therefore possible to temporarily reduce the radial dimensions of the prosthesis to allow its introduction into the heart cavity through access ports having reduced hole diameters and compatible with minimally invasive surgical techniques, in particular with the trans-catheter positioning and cardiac prosthesis implantation techniques according to the present application. In other words, it is possible to insert the cardiac prosthesis 10 into a catheter having a small radial profile, which is able to transport the prosthesis through a minimally invasive access to the heart cavity, in the vicinity of the implantation site, and there carry out its deployment and implantation, functionally replacing the native valve.

[0074] In the following, the different portions into which the prosthesis structure 12 is divided are described in detail.

[0075] The central body 16 is the portion of the prosthesis structure 12 which delimits the passage for the blood through the device. Inside the central body 16, the flexible prosthetic leaflets 14 are fixed, which allow the unidirectional flow of the blood flow inside the catheter, for example as known from the Italian patent No. 20140204 of the same Applicant.

[0076] The central body 16 is a radially foldable elastic structure, which, due to the elastic return, also tends to expand to a diameter greater than the maximum diameter, which maintains the contact, i.e. the closed prosthetic leaflets 14 between the free edges.

[0077] The containment portion 18 is the portion of the prosthesis structure which counteracts and limits the free expansion of the central body 16, preventing it from exceeding the maximum diameter compatible with maintaining the contact between the prosthetic leaflets 14. The containment portion 18 has a substantially annular geometry and is not longitudinally extensible, i.e. it does not significantly change its perimeter extent even when the central body 16 expands inside it while exerting a radial force outwards.

[0078] The containment portion 18 is preferably subdivided into two sub-assemblies 22 substantially in the form of arcs, separated from each other; for simplicity, in the following these two sub-assemblies will be indicated with the term "arc". Each arc 22 can be selectively engaged with the connecting element 20, with which it is stably engaged in the final implantation configuration.

[0079] Each end 24 of each sub-assembly 22 is equipped with an engagement portion 26, preferably able to assume an orientation other than that of a planar ring. In the depicted embodiment, the engagement portions 26 are oriented substantially perpendicularly to the plane of the annulus. In turn, the connecting elements 20 are equipped with pins 28 adapted to be housed in axial holes 27 present in the engagement portions 26. A pair of pins 28 is present on each of the two connecting elements 20, substantially arranged in angular positions diametrically opposite with respect to the central body 16. These pins 28 and the engagement portions 26 present at the ends of the arcs 22 of the containment portion 18 can be provided with barbs or lips or other surface discontinuities intended to create a mechanical interference between these portions and / or to increase the friction in the pin / hole connection, increasing the stability of the connection between the sub-assembly 22 of the containment portion 18 and the connecting element 20. The orientation of the pins 28 with respect to the engagement portions 26 present on the sub-assembly 22 of the containment portion 18 is oriented in a coherent manner so that the pin / hole connection keeps the containment portion in a plane having a congruent geometry with the native valve annulus. Furthermore, the pins 28 are axially pierced to allow the passage of a guide wire, as better described below.

[0080] It is clear that the pin / hole connection mechanism can alternatively comprise pins at the ends of the sub-assembly 22 and cylindrical holes in the connecting element 20. More generally, the pin / hole connection has purely exemplary purposes, without any limitative intent as to the generality of the solution.

[0081] Naturally, the prosthesis can also comprise a different number of sub-assemblies 22. For example, it can comprise a single sub-assembly and thus be formed in an open ring manner. However, the version described using two sub-assemblies 22 is the preferred one, as it allows the use of two guide wires, which, thanks to the guide wire guide device described below, are easier to position correctly than a single guide wire that can remain entangled in the chordae tendinae. However, a third sub-assembly does not simplify the positioning operation and is therefore substantially unnecessary, but should not be excluded.

[0082] In use, the leaflets of the native valve remain trapped within the coupling between the central body 16 and the containment portion 18. Furthermore, the containment portion 18 also has the function of stabilizing the native valve annulus against the radial forces exerted by the central body 16, while having to ensure the effective anchoring of the prosthesis, transferred to the surrounding anatomical morphology, which is generally affected by regressive and dilatative processes, related to the pathology that causes the dysfunction of the atrio-ventricular valves.

[0083] For the sake of clarity, in the following description of the operation of the device, reference will be made to the device in the open ring configuration, i.e. with the connecting elements 20 not connected to each other. Figure 1 and Figure 2In the drawings of the attached figures, and in the subsequent figures, the outer diameter of the central body 16 is illustrated as having a size smaller than the internal dimension of the containment portion 18. In other words, these figures show the two components of the prosthetic structure 12 not in contact with each other in the fully expanded configuration. In fact, the size of the central body 16 can be oversized with respect to the size of the containment portion 18. In this case, there is interference between the two portions of the prosthetic structure 12 and the central body 16 effectively exerts a radial pressure on the containment portion 18 when the latter performs its constraining action on the expansion independently of the thickness of the tissue held captive between the two portions of the prosthetic structure 12. This radial pressure increases the stability of the anchoring to the native leaflets.

[0084] The preferred procedure for implanting the above-mentioned cardiac prosthesis 10 will now be described.

[0085] Initially, access is provided through the femoral or iliac vein. Where possible, access from the femoral vein is preferred as it is significantly simpler and more direct. In particular, it does not require invasive surgery. A guide catheter can be used for the primary purpose of protecting the femoral vein, which has a small caliber.

[0086] The guide catheter, when present, is positioned through the femoral vein to create access to a blood vessel with a larger diameter. The main catheter 32 is then inserted, which, when provided, slides within the guide catheter, reaching the right atrium through the inferior vena cava IVC, as shown in Figure 3 .

[0087] The main catheter 32 is provided with a distal deflection system so that its end 34 can be bent by the operator in the direction of the left atrium. A puncture is then made in the septum S between the two atria, allowing access to the left atrium. Inside the main catheter 32, the guide wire introducer device 36 is inserted.

[0088] As mentioned above, the provision of the guide catheter is not mandatory, but it is possible to use directly the main catheter 32 which enters the right atrium through the inferior vena cava. In addition, it is also possible to insert the main catheter to a position inside the left atrium. This allows the guide wire introducer device 36 to be inserted directly into the left atrium.

[0089] The guide wire introducer device 36 is a device whose function is to allow the deployment of a guide wire around the leaflets of the native mitral valve V, which is necessary for the subsequent positioning of the cardiac prosthesis 10.

[0090] The guide wire introducer device 36 comprises a first catheter 40, inside which a second catheter 44 and a third catheter 45 slide. The first catheter 40 is a single-lumen catheter. It is provided with a distal deflection system so that its end 42 can be oriented by the operator in the direction of the mitral valve V.

[0091] In the detailed Figure 4 and Figure 5The second catheter 44, which can be better seen in the figure, comprises two lumens 46 and 48, which are adapted to slide a guide wire therein. The two lumens are arranged parallel to each other and side by side over a larger portion of the second catheter 44. In the end 50 of the second catheter 44, the two lumens are bent in substantially opposite directions over an angle of about 90°. Thus, the two lumens 46 and 48 do not terminate in the distal tip 51 of the catheter 44, but in its lateral face, in diametrically opposite positions in the respective holes 41 and 43. In other words, the two guide wires inserted in the lumens 46 and 48 exit from the second catheter 44 oriented in diametrically opposite directions.

[0092] The second catheter 44 also comprises a deflection system. The deflection system according to the exemplary embodiment depicted comprises a wire 52. The wire 52 is fixed to the end 50 of the catheter, passes through a small portion from the outside of the catheter and then extends inside the catheter. The operator can pull the wire 52 in order to establish a curvature to the second catheter 44 which can be very pronounced, as Figure 4 can be clearly seen in the figure. The curvature is greater than 90°. However, it is not impossible to use other deflection systems. For example, a segment of shape memory material can be included within the second catheter, so that it can be inserted in the first catheter 40 in a stretched state and recover the correct curvature when it is pushed out of the first catheter 40. Figure 5a An example of such a configuration is shown in the figure, in which a wire 152 of shape memory material, for example titanium-nickel alloy (nitinol), is incorporated within the second catheter 144.

[0093] A segment 53 of radiopaque or echolucent material is provided at the distal tip 51. The segment 53 is embedded within the distal tip 51, which is preferably circular to prevent accidental injuries.

[0094] As better described hereinafter, the third catheter 45 is also inserted within the first catheter 40 and receives therein a guide wire capture device 47 (snaring device), as better described hereinafter. It can be noted that the guide wire capture device depicted, which comprises different foldable loops or circuits combined together, is one of the many possible capture devices that can be used, which have been found particularly effective for the specific application. However, different capture devices are not excluded, for example with a single loop or a different number than one of the depicted devices.

[0095] Turning now to the process of implanting the cardiac prosthesis, the guide wire introducer device 36, which has been inserted inside the main catheter 32, is pushed inside the left atrium Figure 3 , through the septum S. It can be noted that the end 34 of the main catheter 32 can be located in the right atrium, as shown in the figure, or in the left atrium. The end 42 of the first catheter 40 of the guide wire introducer device 36 is bent so that it is directed towards the valve V, and therefore towards the bottom in the Figure 6 .

[0096] sliding the second catheter 44 of the guidewire guide device 36 within the first catheter 40 of the guidewire guide device 36 Figure 6 ); the end 50 exits and assumes a clear curvature, which is directed in the opposite direction to the curvature of the end 42 of the first catheter 40. The second catheter 44 is in fact bent upwards in Figure 6 .

[0097] The guidewire guide device 36 is further advanced within the main catheter 32 Figure 7 ) and the second catheter 44 is pushed through the valve V into the left ventricle.

[0098] Once the second catheter 44 of the guidewire guide device 36 is inside the left ventricle, it is slightly retracted so that its distal tip 51 is positioned behind the posterior leaflet of the native valve. In particular, the distal tip 51 is preferably positioned behind the central segment (sector) generally designated P2. To this end, the presence of a segment 53 of radiopaque material at the distal tip 51 is particularly advantageous. If there is doubt about the correct positioning or orientation of the catheter end 50, it can in fact be verified directly with an ultrasound probe or by fluoroscopy. The segment 53 of radiopaque material will be oriented in a direction tangent to the edge of the valve.

[0099] Figure 8 A detailed schematic view of the left ventricle is shown, in which the native mitral valve V is clearly visible, with the two chords T and the aortic valve A. The end 50 of the second catheter 44 of the guidewire guide device 36 is depicted in the correct positioning condition behind the posterior leaflet of the native valve V. It can be noted that the catheter 44 does not pass through the chord bundle.

[0100] Reference is now made to Figure 9 in which the third catheter 45, with the guidewire capture device 47, slides within the first catheter 40 until it is introduced inside the left ventricle. The second catheter also has a deflection system 56 near its end 54. This deflection system can in general be identical to the wire 52 described above with reference to the second catheter 44. According to a preferred variant, however, for structural simplicity it is made with a wire that slides within the catheter wall; a flexible metal structure with a rigid backbone embedded in the thickness of the catheter produces a bending effect. However, other known mechanisms in the prior art should not be ruled out. Furthermore, the guidewire capture device 47 is inserted into a covering sheath 55.

[0101] The third catheter 45 is oriented so that the end 54 is bent in the opposite direction to the curvature of the end 50 of the second catheter, thus in the direction of the aortic valve. The guidewire capture device 47 is pushed out of the respective third catheter 45 and sheath 55 until it is positioned in the LVOT (left ventricular outflow tract), i.e. before the aortic valve.

[0102] By keeping the guidewire capture device 47 in this position, the first guidewire 56 is inserted into the first lumen 46 of the second catheter of the guidewire guide device 36. The end 57 of the guidewire 56 is pushed by the operator into the ventricle. Figure 10 Due to the precise positioning of the distal tip 51 of the second catheter 44, the lateral position of the outlet 41 of the lumen 46, the heart anatomy and the influence of the blood flow during systole which is naturally directed towards the aortic valve A, the end 57 of the guidewire 56 is driven around the valve and in the direction of the LVOT. Once it reaches the LVOT, it is captured by the guidewire capture device 47 which has been pre-positioned. Subsequently, the end 57 of the guidewire 56 is withdrawn by withdrawing the third catheter 45.

[0103] Alternatively, the guidewire capture device 47 can also be positioned inside the aorta, i.e. beyond the aortic valve A. The guidewire will be pushed by the blood flow into the aorta and thus the capture operation can be performed.

[0104] Once the end 57 of the guidewire 56 has been captured, the guidewire 56 forms a half loop around the valve V. Figure 11

[0105] In a substantially symmetrical manner, a similar half loop is formed around the valve V with a second guidewire 58 inserted into the second lumen 48 of the second catheter 44. In this way, the valve V is completely surrounded by two guidewires 56 and 58 which are correctly positioned. For this purpose, the same guidewire capture device 47 used for capturing the first wire can be used, or preferably, another guidewire capture device 47 is also received in the third catheter 45. In this case, the third catheter 45 preferably has a double lumen.

[0106] Naturally, a guidewire positioning device similar to the one described in detail above can also be used in order to position a single guidewire performing a complete loop around the native valve. However, in this case, the guidewire positioning procedure becomes more complex: while the number of required steps is less (it is not necessary to repeat these steps for the second wire), it is not easy to direct the guidewire around the entire valve in a sufficiently precise manner, since there is a risk of becoming entangled in the chordae tendinae. In fact, the use of two guidewires allows to exploit the geometry of the heart and the natural blood flow to facilitate the operation and minimize the risk of errors which, if not immediately identified and corrected, can have serious consequences for the patient.

[0107] Reference is now made to Figure 12 ​, the first and second catheters 40 and 44 are preferably left in place in order to facilitate the insertion of the two arcs 22 constituting the containment portion 18 of the cardiac prosthesis 10 into the ventricle. The two arcs are inserted on the wires, i.e. by sliding on the guide wires. In other words, the longitudinal channel extending through one of the two arcs is used in order to insert the end 57 of the guide wire 56 just recovered therein; similarly, the end of the guide wire 58 is inserted in the longitudinal channel extending through the other arc. The two arcs 22 are then pushed until they exit the first catheter 40 and enter the heart. The arcs 22 are pushed until they come into contact with the tip 51 of the second catheter 44. At this point, the first and second catheters 40 and 44 can be removed.

[0108] The main catheter 32 is preferably left in place and is subsequently used to introduce therein the device 60 for implanting the cardiac prosthesis, with insertion of the central body 16. In any case, the removal of the main catheter 32 or its replacement with another catheter is not excluded.

[0109] The device 60 for implanting the cardiac prosthesis, the details of which can be seen in Figure 13 、 14 and 15, comprises a catheter 61 through which all the other elements and the central body 16 of the prosthesis are inserted.

[0110] The device for implanting the cardiac prosthesis also comprises a release device 62 for the central body 16 of the prosthesis. The release device 62 is adapted to be inserted in the catheter to advance the central body 16 of the prosthesis therein. The device 60 for implanting the cardiac prosthesis also comprises a device 64 for assisting the connection operation between the central body 16 and the subassemblies of the containment portion 18. This auxiliary device 64 comprises an assembly of catheters 66, with at least two catheters for each arc of the containment portion, which are combined together in the same sheath 68, which partially covers the catheters and leaves at least one free end 70 for each catheter.

[0111] In the preferred case depicted, in which the prosthesis comprises two arcs 22, the auxiliary device 64 comprises four catheters 66. Naturally, if the prosthesis comprises a single subassembly of the containment portion 18, two catheters are sufficient. However, if the prosthesis comprises three or more subassemblies, six or more catheters will be provided.

[0112] The catheters 66 are incompressible in the longitudinal direction and are flexible. Furthermore, they are fixed inside the sheath 68 so that they do not slide with respect to each other. Preferably, the sheath 68 also comprises a free longitudinal lumen 72, in which, if advantageous, a guide wire can slide.

[0113] Turning now to the implantation process of the cardiac prosthesis 10, for each arc 22 of the containing portion 18, the two ends of the guide wires 56, 58 that extend through them are inserted into the respective pins 28 of the two connecting elements 20 and then in the catheter 66 of the auxiliary device 64. For example, the guide wire 56 is passed in sequence through the first catheter 66, the first pin 28 of the first connecting element 20, the arc 22, the first pin 28 of the other connecting element 20 and the second catheter 66, as can be seen in the figure Figure 13 It can be seen.

[0114] The catheter 61 is then forced to advance within the main catheter 32 and through the mitral valve until its end 63 is inside the left ventricle. Although for greater clarity, Figures 16 to 19 Only the devices are shown, but the operations shown therein are generally performed inside the heart of a patient.

[0115] The central body 16 is then pushed so as to advance further inside the catheter 61 until the connecting elements 20 are released from the catheter. It can be noted that, when the central body 16 is in the folded configuration, the connecting elements are deformed in order to be able to slide inside the catheter. However, they are made of shape memory material, so that as soon as they exit the catheter they immediately take the intended configuration.

[0116] In order to connect the central body 16 and the containing portion 18, or in other words in order to engage the arcs 22 with the connecting elements 20, it is now sufficient to pull the end of each guide wire Figure 17 ). In this way, the pins 28 of the connecting elements 20 are inserted into the axial holes 27 of the junctions 26 located at the ends of the circular arcs 22. It can be noted that, in order to tighten, the presence of the auxiliary device 64, and in particular of the catheter 66, is essential. In fact, the incompressible catheter 66 allows the guide wires to be pulled without kinking against the edges of the catheter 61. In other words, the catheter allows the traction force that would otherwise not be able to be exerted to be transmitted to the portion of guide wire inside each arc, which is sufficient to connect the arcs 22 and the connecting elements 20 to each other.

[0117] Once the components of the prosthesis are fixed to each other, the guide wires, as well as the auxiliary device 64, can be withdrawn Figure 18 ).

[0118] The prosthesis is therefore assembled and held in the correct position, the central body 16 is still inside the catheter 61, the two arcs 22 are correctly oriented with respect to each other, thus constituting the containing portion 18 of the prosthesis Figure 19 and 20 ).

[0119] By acting on the release device 62 and the catheter 61, the central body 16 of the prosthesis is forced to advance within the catheter 61 while the catheter 61 is withdrawn. The central body remains substantially in a stable position within the heart so that the receiving portion 18 does not lose contact with the annulus of the native valve when the catheter 61 is withdrawn. When the central body 16 is released from the catheter 61, it expands within the native valve until it is constrained by the receiving portion 18 ( Figure 21 ). The leaflets of the native valve thus remain trapped between the central body of the cardiac prosthesis and the receiving portion 18. This configuration results in a stable and secure positioning of the prosthesis.

[0120] All that has been described above must naturally be understood as a possible embodiment of the present invention, and not the only embodiment. In an exemplary manner, some variations of the above objects will now be described. However, it should be understood that this is not an exhaustive list of possible variations.

[0121] According to a variant of the invention, Figure 22 The second and third catheters 244, visible in the cross-section of FIG, slide within the first catheter 40 of the guidewire introducer device 36. The second catheter 244 provides two lumens 46 and 48 suitable for sliding a guidewire therethrough. Unlike the second catheter 44 described above, the catheter 244 has a D-shaped cross-section. Preferably, the second catheter 244 provides an additional lumen 250 for passage of the deflection system wire 52 of the distal portion of the catheter.

[0122] The third catheter 254 also has two lumens 45a, 45b adapted to accommodate two guidewire capture devices 47. The third catheter 245 also has a D-shaped cross section that is complementary to the cross section of the second catheter 244. In this way, a correct mutual orientation between the catheters 244 and 245 is ensured, and thus a correct mutual orientation between the guidewires inserted into the lumens 46 and 48 and the guidewire capture devices 47 is ensured, thereby allowing the guidewires to be positioned around the annulus more easily.

[0123] In this regard, it is clear that the D-shape is intended to be understood as exemplary: the cross-sections of the two conduits 244 and 245 are sufficient to ensure that the correct relative orientation is maintained. For example, the cross-sections of the two conduits 244 and 245 are complementary to each other within the conduit 40 (in other words, the two juxtaposed cross-sections correspond to the cross-section of the first conduit 40 of the guidewire introducer device 36) and the two conduits 244 and 245 include at least one planar abutment surface 270 and 272, respectively. It should be understood that the conduits 244 and 245 can slide independently within the first conduit 40. A single lumen 45a can also be provided.

[0124] The third catheter 245 also has an additional lumen 260 for passage of a wire of a deflection system at the distal portion of the catheter.

[0125] Now refer to Figures 23 to 26 The second and third catheters 344 and 345 can comprise a metal structure that can be mechanically bent. These metal structures constitute the lumens 346 and 348 of the second catheter 344 and the lumens 345a, 345b of the third catheter 345. Each lumen 346 and 348 has a wire 352 that allows it to be bent. Preferably, each lumen 346 and 348 can form two curves. The first curve is greater than 90°, preferably between 120° and 180°; the second curve is about 90°. Preferably, the two curves lie in two mutually perpendicular planes. These two curves are obtained by means of respective portions 354 and 356, which are suitably perforated to create anisotropic portions that advantageously ensure the precise and univocal orientation of the lumens. This variant also allows all the lumens to be straightened before the second and third catheters are removed. In this way, the friction associated with the catheter 40, in which the catheters 344 and 345 slide, is greatly reduced, as is the friction associated with the guide wire in which they slide, making it easier and faster to withdraw the second and third catheters. Furthermore, the metal lumens have a particularly small thickness.

[0126] The catheters 344 and 345 slide within the catheter 40 in a straightened configuration Figure 24 When they are externalized from the catheter 40, the deflections are then activated to bend the portion 354 and create the first curve Figure 25 The distal deflection of the portion 356 is then activated to create the second curve Figure 26 In a substantially similar manner, the deflections on the lumens 345a and 345b of the third catheter are also activated. At the end of the operation of positioning the guide wire, all the lumens are straightened Figure 24 to extract them.

[0127] Naturally, the principle of the application remaining the same, the forms of implementation and the details of construction can be widely varied with respect to those described and illustrated, without thereby departing from the scope of the application.

Claims

1. A device for implanting a cardiac prosthesis, comprising a central body (16) and a receiving portion (18) having one or more subassemblies (22), the device for implanting a cardiac prosthesis comprising: - a release device for the central body, which can be inserted into the catheter, - Means for assisting the connection operations between the subassemblies of the central body (16) and the housing portion (18), comprising an assembly of conduits, wherein for each subassembly of the housing portion there are at least two conduits, the conduits being connected to one another over a portion thereof and each conduit having at least one free end. 2 . The device for implanting a cardiac prosthesis according to claim 1 , wherein the catheter constituting the catheter assembly is incompressible in the longitudinal direction.

3. The device for implanting a cardiac prosthesis according to claim 1, wherein the catheter constituting the catheter assembly is flexible.

4. The device for implanting a cardiac prosthesis according to claim 1, wherein the catheter constituting the catheter assembly is incompressible and flexible in a longitudinal direction.

5. The device for implanting a cardiac prosthesis according to any one of claims 1 to 4, wherein the catheters constituting the catheter assembly are combined in a same sheath, the sheath combining the catheters together along a portion thereof.

6. The device for implanting a cardiac prosthesis according to claim 5, wherein the sheath further comprises a longitudinal lumen (72).

7. The device for implanting a cardiac prosthesis according to any one of claims 1 to 4, wherein there are at least two subassemblies (22) of the receiving portion (18) and there are at least four catheters of the catheter assembly.

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