Fibrillated mesh for a medical implant and medical implant including the same

Abstract

The present invention provides a fibrillated mesh (100) for a medical implant (300), said medical implant (300) comprising at least one medical support structure (200), said fibrillated mesh (100) being configured to at least partially cover said medical support structure (200) to facilitate integration of the medical implant (300) with a native tissue (T) of a patient and promote tissue formation. The invention further provides a medical implant (300) comprising at least one fibrillated mesh (100) as defined above and at least one medical support structure.

Description

[0001] Fi bri Hated mesh for a medical implant and medical implant including the same

[0002] The present invention belongs to the technical field of medical devices, implants and techniques for providing structural support and promoting tissue formation in a bodily lumen of a patient.

[0003] Medical implants can be adapted for use in minimally-invasive endovascular procedures.

[0004] As a non-limiting example, medical implants of this kind may comprise medical support structures such as stents, scaffolds, endovascular grafts, stent grafts, covered stents, Transcatheter Aortic Valve Implant (TAVI), Left Atrial Appendage Closure (LAAC), or Right Atrial Appendage Closure devices.

[0005] When minimally-invasive endovascular procedures are performed, complications may occur due to malapposition of medical support structures, e.g. grafts, stents, scaffolds or valves, in particular when treating calcified lesions, which may cause the generation of cavities on a surface of a bodily lumen.

[0006] This may result in leakage of blood around instead of through the medical implant.

[0007] In particular, malapposition of medical support structures may cause complications such as endoleaks, paravalvular regurgitation, and / or peridevice leaks.

[0008] Endoleaks refer to the persistent flow of blood into an aneurysm sac, e.g. following the placement of an endovascular graft, when treating aortic aneurysms.

[0009] In particular, endoleaks may occur as a consequence of incomplete sealing or adherence of a medical support structure, e.g. an endovascular graft, with respect to the vessel wall.

[0010] Endoleaks are classified into different types, in particular Type I to Type V, as schematically illustrated in Fig. 1.

[0011] The above-mentioned complications mostly concern Type I endoleaks, occurring when a gap arises between a medical support structure, e.g. an endovascular graft, and a native artery at either the proximal (Type la endoleaks) or distal (Type lb endoleaks) end of the medical implant, allowing blood to flow into the aneurysm sac through this gap.

[0012] This flow of blood to the aneurysm sac may lead to ongoing pressurization, which poses a risk of aneurysm enlargement or rupture. Therefore, addressing Type 1 endoleaks is necessary to ensure long-term success of endovascular aneurysm repair (EVAR).

[0013] Other types of endoleaks may be related to retrograde flow into the aneurysm sac through side-branchen (Type II), defect of the graft (Type III), porosity of the graft (Type IV), and increasing aneurysm without identifiable endoleaks (Type V) (Fig. 1).

[0014] Paravalvular regurgitation represents a similar complication, which is associated with transcatheter aortic valve implant (TAVI) or other procedures involving the placement of artificial heart valves.

[0015] When calcified lesions are present, such as in case of aortic stenosis, the risk of paravalvular regurgitation increases.

[0016] In particular, paravalvular regurgitation refers to the leakage of blood around a prosthetic valve, typically at the annular level, rather than through the valve leaflets themselves.

[0017] In particular, when calcified lesions are concerned, the native aortic valve may be heavily calcified, making it challenging for the prosthetic valve to achieve a proper seal with the native tissue of the patient.

[0018] This lack of sealing may result in paravalvular regurgitation, where blood leaks between the prosthetic valve and the surrounding native tissue.

[0019] This regurgitation can lead to various and potentially severe complications, including heart failure, hemodynamic instability, and / or the need for surgical re-intervention.

[0020] Peridevice leaks may occur after occluding left atrial appendage.

[0021] Occlusion of the left atrial appendage is becoming an increasingly common approach in preventing strokes in individuals with atrial fibrillation.

[0022] Nevertheless, there is a notable occurrence of leaks around the device following this surgical procedure.

[0023] This has recently been linked to an increased likelihood of future ischemic events.

[0024] Type I endoleaks mostly occur when the distal and proximal ends of a medical support structure, e.g. a valve, are not fixed against the lumen of the native artery, leaving room for blood to flow around the valve into the aneurysm sac. Another mode of failure may be that the aneurysm neck progressively dilates after implantation of the endograft, for which the anchor point of the medical device detaches from the native wall causing an endoleak.

[0025] This can both happen at the inflow and outflow track.

[0026] Similarly, in paravalvular regurgitation, the valve is not well-placed against the aortic wall, leaving space for blood to flow around the valve.

[0027] This is especially likely to occur when the aorta is heavily calcified.

[0028] Also, when LAAC devices are implanted, an insufficient closure can lead to blood leaking into the left atrial appendage, causing further ischemic events.

[0029] The reasons for these leaks are twofold.

[0030] A first reason for these leaks is related to the rough and uneven lumen surface e.g. characterizing calcified lesions, which leads to the generation of gaps between the medical implant and the native tissue of the patient, through which blood can flow.

[0031] A second reason for these leaks is related to the medical implant not being properly integrated with, and thus reliably attached to, the surrounding native tissue of the patient.

[0032] JP7322115B2 discloses a polyurethane thermoset shape memory polymer (SMP) foam used to seal a space around implanted valves.

[0033] However, the used SMP foam does not enable to actively regenerating vascular tissue.

[0034] To the contrary, it only seals the valve so that blood cannot leak around the same.

[0035] US20220273852A1 discloses a process for treating an abdominal aortic aneurysm (AAA) endoleak with a shape memory polymer (SMP) foam device.

[0036] Here, the embolic SMPO foam expands and conforms to the aneurysm wall to counter blood flow from leaking around the graft.

[0037] However, similar as above, this known solution only allows preventing blood leakage, but does not enable promoting integration between the medical implant and the native tissue of the patient.

[0038] US11141273B2 discloses an occluder device for occluding a gap between a prosthetic heart valve and an adjacent body tissue, said occluder device comprising a conformable body having a hollow interior, a leading end and a trailing end, and a port which is arranged at the trailing end of the body and is in fluid communication with the interior of the body.

[0039] Securing features are provided to couple the occluder device to the prosthetic heart valve and the adjacent body tissue, said securing features being based on a fillable chamber having a delivery, pre-deployment configuration and a final, post-deployment configuration.

[0040] Similar as above, this known solution is only capable of preventing a blood flow from going around the valve.

[0041] However, the occluding device according to US11141273B2 is not adapted to promote integration of the medical implant with the native tissue of the patient.

[0042] EP3777770A1 discloses a solution comprising a stent, a plurality of leaflets for defining a prosthetic valve, an inner skirt, an outer skirt, and a paravalve seal designed for sealing against surrounding tissue.

[0043] In some examples, the paravalve seal comprises a material that swells in response to contact with blood. Also, said paravalve seal may comprise a flap or pocket that is distensible in response to back-pressure and / or paravalve back-flow of blood.

[0044] Again, this known solution only provides a sealing mechanism, rather than a solution that further promotes integration of the medical implant with the native tissue of the patient.

[0045] US20220088273A1 discloses a medical implant for enhanced durability and wear reduction, said medical implant comprising a medical implant support structure, an electrospun cover layer, covering at least a portion of the medical implant support structure, and an electrospun medical implant layer covering the electrospun cover layer. The electrospun cover layer configures an in-between layer provided between said portion of the medical implant support structure and the electrospun medical implant layer.

[0046] However, this known solution is directed at providing protection for the electrospun layer rather than promoting fusion between the medical support structure and the native tissue of the patient.

[0047] Therefore, there is the need for an improved solution allowing to promote integration of a medical implant, in particular an endovascular medical implant, with a surrounding native tissue of the patient, thereby preventing the occurrence of complications such as endoleaks, paravalvular regurgitation, and / or peridevice leaks, even in case of calcified or highly-calcified lesions. In the light of the above, it is an object of the present invention to provide a fibrillated mesh for use in a medical implant, said medical implant comprising a medical support structure such as a graft, stent, scaffold or valve, which facilitates optimized integration of the medical implant with a native tissue of the patient and tissue formation, thereby preventing complications such as endoleaks, paravalvular regurgitation, and / or peridevice leaks, even in case of calcified or highly-calcified lesions.

[0048] It is also an object of the present invention to provide a medical implant comprising at least one fibrillated mesh as recited above and at least one medical support structure.

[0049] These objects are achieved by the provision of a fibrillated mesh as defined in claim 1.

[0050] Accordingly, a fibrillated mesh for a medical implant is provided, said medical implant comprising at least one medical support structure, said fibrillated mesh being configured to at least partially cover said medical support structure to facilitate integration of the medical implant with a native tissue of a patient and promote tissue formation.

[0051] Provided is also a medical implant comprising at least one fibrillated mesh as defined above and at least one medical support structure, as described in more detail in the following.

[0052] The present invention provides a fibrillated mesh for a medical implant.

[0053] The medical implant comprises a medical support structure.

[0054] The fibrillated mesh is configured to at least partially cover said medical support structure.

[0055] This allows facilitating integration of the medical implant with a native tissue of a patient and promote tissue formation.

[0056] The invention is based on the basic idea that, by the provision of a fibrillated mesh as defined above, it is possible to enhance integration of the medical implant with a surrounding native tissue of the patient, thereby preventing the occurrence of malapposition, even in case of calcified or highly-calcified lesions.

[0057] Accordingly, the occurrence of complications such as endoleaks, paravalvular regurgitation, and / or peridevice leaks can be largely prevented.

[0058] Also, the fibrillated mesh allows exposing leaks to the medical support structure, e.g. a microfiber meshed structure, triggering a natural healing response that facilitates integration of the medical implant with the surrounding native tissue of the patient and promotes tissue formation.

[0059] Conveniently, the fibrillated mesh can be made of staggered fibers.

[0060] Conveniently, the fibrillated mesh may have a sponge-like structure.

[0061] In particular, the sponge-like structure of the fibrillated mesh allows effectively filling-up cavities and / or adapt and adhere to bulging portions that may be present on a surface of a bodily lumen.

[0062] The presence of cavities and / or bulging portions may generate gaps between the medical implant and the native tissue of the patient, potentially hindering adhesion of the implant to the native tissue.

[0063] By using a sponge-like fibrillated mesh, integration of the medical implant with the surrounding native tissue is facilitated.

[0064] For instance, surface cavities may derive from surface roughness and unevenness characterizing calcified lesions. Bulging portions are also a common consequence of calcified lesions. Advantageously, the fibrillated mesh can be resorbable.

[0065] Advantageously, the fibrillated mesh can be a fibrillated skirt.

[0066] In the present context, the definition “skirt” denotes an element that is adapted to fully or partially cover a medical implant over its circumference.

[0067] Preferably, said fibrillated skirt is a resorbable fibrillated skirt.

[0068] Conveniently, the fibrillated mesh can be obtained through electrospinning.

[0069] Alternatively, the fibrillated mesh can be obtained through electro-spraying.

[0070] Alternatively, the fibrillated mesh can be obtained through electro-writing.

[0071] Alternatively, the fibrillated mesh can be obtained through melt-electrospinning.

[0072] Alternatively, the fibrillated mesh can be obtained through 3D-printing.

[0073] The above-recited techniques, all known in the art, allow for easily manufacturing of the fibrillated mesh. Also, said techniques allow obtaining a fibrillated mesh that can be easily applied to any shape and even adapted to an already existing medical implant.

[0074] The present invention further provides a medical implant.

[0075] The medical implant may be adapted for minimally-invasive implantation.

[0076] For instance, said medical implant may be adapted for use in minimally-invasive endovascular procedures.

[0077] The medical implant comprises at least one fibrillated mesh as defined above.

[0078] For instance, the medical implant may comprise a single fibrillated mesh.

[0079] Alternatively, the medical implant may comprise two or more fibrillated meshes. The medical implant further comprises at least one medical support structure.

[0080] For instance, the medical implant may comprise a single medical support structure.

[0081] Alternatively, the medical implant may comprise two or more medical support structures.

[0082] The fibrillated mesh is configured to at least partially cover the at least one medical support structure to facilitate integration of the medical implant with a native tissue of a patient and promote tissue formation.

[0083] In one configuration, the at least one fibrillated mesh can be configured to entirely cover the medical support structure.

[0084] In an alternative configuration, the at least one fibrillated mesh can be configured to partially cover the medical support structure.

[0085] Here, the at least one fibrillated mesh can be configured to cover the medical support structure at its distal end and / or proximal end.

[0086] Different arrangements of the at least one fibrillated mesh and the at least one medical support structure are possible according to the invention.

[0087] In particular, the fibrillated mesh can be interposed between the medical support structure and the native tissue of the patient.

[0088] Alternatively, the medical support structure can be interposed between the fibrillated mesh and the native tissue of the patient. According to a further alternative, the medical support structure can be sandwiched between a first fibrillated mesh and a second fi bril lated mesh.

[0089] Here, the first fibrillated mesh is arranged between one side of medical support structure and the native tissue of the patient, while the second fibrillated mesh is arranged at the opposite side of the medical support structure.

[0090] According to yet another alternative, the fibrillated mesh can be interwoven with the medical support structure.

[0091] Conveniently, selection between different arrangements of the at least one fibrillated mesh and the at least one medical support structure is carried out on a case-by-case basis, in the light of medical implant and use in the anatomical location.

[0092] The medical support structure can be an endovascular graft.

[0093] In particular, this is convenient to prevent the occurrence of endoleaks, in particular Type I endoleaks.

[0094] Alternatively, the medical support structure can be a valve replacement, e.g. a pulmonary valve replacement, an aortic valve replacement, a mitral valve replacement, or a tricuspid valve replacement.

[0095] As a further alternative, the medical support structure can be a Transcatheter Aortic Valve Implant (TAVI).

[0096] In particular, this is convenient to prevent the occurrence of paravalvular regurgitation.

[0097] According to yet another alternative, the medical support structure can be a Left Atrial Appendage Closure (LAAC) device. In particular, this is convenient to prevent the occurrence of peridevice leaks.

[0098] Still further, the medical support structure can be a Right Atrial Appendage Closure device.

[0099] According to further alternatives, the medical support structure can be a stent, a scaffold, a stent graft or a covered stent.

[0100] Also, the medical support structure can be a closure device, e.g. a septum closure device or a vascular closure device, or an occluder, e.g. a Ventricular Septal Defect (VSD) occluder, a Septal occluder, a Patent Foramen Ovale (PFO) occluder, and a Left Atrial Appendage (LAA) occluder. Further details and advantages of the present invention shall now be disclosed in connection with the drawings, where:

[0101] Fig. 1 is a diagram schematically showing different types of endoleaks, namely endoleaks Types I to V;

[0102] Fig. 2 is a schematic view showing a fibril lated mesh according to an embodiment of the invention (right side). The fibrillated mesh can be arranged to at least partially cover a medical support structure (left side). According to an embodiment of the invention, a medical implant comprises at least one fibrillated mesh and at least one medical support structure;

[0103] Figs. 3a-b are schematic views illustrating how tissue ingrowth is accomplished using the medical implant of the invention. Here, the medical support structure is omitted for simplification;

[0104] Figs. 4a-b is a schematic view showing the ability of a sponge-like structure of the fibrillated mesh (a) to fill-up a cavity that is present on a surface of a bodily lumen, or (b) to adapt and adhere to a bulging portion of a tissue. Surface cavities and bulge portions are common consequences of calcified lesions;

[0105] Fig. 5 is a schematic view showing a detail of a first configuration of the medical implant according to the invention. Here, the fibrillated mesh is configured to entirely cover the medical support structure;

[0106] Fig. 6 is a schematic view showing a first arrangement of the fibrillated mesh and the medical support structure in the configuration of Fig. 5;

[0107] Fig. 7 is a schematic view showing a second arrangement of the fibrillated mesh and the medical support structure configuration of Fig. 5;

[0108] Fig. 8 is a schematic view showing a third arrangement of the at least one fibrillated mesh and the medical support structure in the configuration of Fig. 5. Here, a first fibrillated mesh and a second fibrillated mesh are provided, sandwiching the medical support structure;

[0109] Fig. 9 is a schematic view showing a fourth arrangement of the fibrillated mesh and the medical support structure in the configuration of Fig. 5; Fig. 10 is a schematic view showing a detail of a further configuration of the medical implant according to the invention. Here, the fibrillated mesh is configured to partially cover the medical support structure. In particular, the fibrillated mesh is illustrated covering the medical support structure at its proximal and distal ends;

[0110] Fig. 11 is a view showing an arrangement that is similar to that of Fig. 6, but referring to the configuration of Fig. 10;

[0111] Fig. 12 is a view showing an arrangement that is similar to that of Fig. 7, but referring to the configuration of Fig. 10;

[0112] Fig. 13 is a view showing an arrangement that is similar to that of Fig. 8, but referring to the configuration of Fig. 10;

[0113] Fig. 14 is a view showing an arrangement that is similar to that of Fig. 9, but referring to the configuration of Fig. 10.

[0114] Fig. 2 shows a fibrillated mesh 100 (right side of the figure) according to an embodiment of the invention.

[0115] The fibrillated mesh 100 is adapted for use in a medical implant 300 comprising at least one medical support structure 200, such as the medical support structure 200 shown in Fig. 2 (left side of the figure).

[0116] The fibrillated mesh 100 is configured to at least partially cover the medical support structure 200.

[0117] This facilitates integration of the medical implant 300 with a native tissue T of a patient and promotes tissue formation.

[0118] In the present embodiment, the fibrillated mesh 100 is made of stagged fibers.

[0119] Not shown is that other configurations are also possible according to the invention.

[0120] Fig 3 schematically illustrates how the fibrillated mesh 100 of the invention promotes tissue ingrowth. Here, the medical support structure 200 is omitted for simplification.

[0121] First, the fibrillated mesh 100 is arranged to at least partially cover a target portion of a native tissue T of a patient, as shown in Fig 3(a).

[0122] Then, tissue starts to naturally grow within the fibrillated mesh 100, as shown in Fig 3b. In the present embodiment, the fibrillated mesh 100 has a sponge-like structure 10 (Fig. 2).

[0123] This sponge-like structure 10 allows to effectively filling-up cavities C that may be present on a surface of a bodily lumen, as illustrated in Fig. 4(a).

[0124] The sponge-like structure 10 is also capable of adapting and adhering to bulge portions B that may be present on a surface of a bodily lumen, as illustrated in Fig. 4(b).

[0125] The presence of surface cavities C and / or bulge portions B formed on a surface of a bodily lumen are common consequences of calcified lesions. For example, surface cavities C and / or bulge portions B may generate as a consequence of surface unevenness and roughness characterizing calcified lesions.

[0126] The sponge-like structure 10 allows improving integration of the medical implant 300 with a surrounding native tissue T of the patient, thereby avoiding the occurrence of malapposition and preventing complications such as endoleaks, in particular Type I endoleaks, paravalvular regurgitation, and / or peridevice leaks.

[0127] Also, tissue formation can be enhanced.

[0128] In the present embodiment, the fibrillated mesh 100 is resorbable.

[0129] Alternatively, the fibrillated mesh 100 can be non-resorbable.

[0130] Conveniently, the fibrillated mesh 100 can be a skirt, preferably a resorbable skirt.

[0131] As mentioned, in the present context, the definition “skirt” denotes an element that is adapted to fully or partially cover a medical implant over its circumference.

[0132] The fibrillated mesh 100 may be obtained through one among: electrospinning; electro-spraying; electro-writing; melt-electrospinning, or

[0133] 3D-printing.

[0134] The above-mentioned techniques are well-known in the art and therefore not further described for the sake of brevity. According to an embodiment of the invention, a medical implant 300 comprises at least one fibrillated mesh 100, such as the fibrillated mesh 100 described in the foregoing (Fig. 2, left side), and at least one medical support structure 200.

[0135] An exemplary medical support structure 200 for use in the medical implant 300 is schematically shown in Fig. 2 (left side).

[0136] The fibrillated mesh 100 is configured to at least partially cover the at least one medical support structure 200, to facilitate integration of the medical implant 300 with a native tissue T of a patient and promote tissue formation.

[0137] The medical implant 300 may comprise a single fibrillated mesh 100.

[0138] Alternatively, the medical implant 300 may comprise two or more fibrillated meshes 100.

[0139] In the described configurations, the medical implant 300 comprises a single medical support structure 200.

[0140] Not shown is that, alternatively, the medical implant 300 may comprise a plurality, e.g. two, medical support structures 200.

[0141] The medical implant 300 may be adapted for minimally-invasive implantation. In particular, the medical implant 300 can be adapted for use in minimally-invasive endovascular procedures.

[0142] The fibrillated mesh 100 can be resorbable.

[0143] Alternatively, the fibrillated mesh 100 can be non-resorbable.

[0144] Fig. 5 shows a first configuration of the medical implant 300 according to the invention.

[0145] Here, the fibrillated mesh 100 is configured to entirely cover the medical support structure 200.

[0146] Figs. 6-7 schematically illustrate respective arrangements of the at least one fibrillated mesh 100 and the medical support structure 200, in the configuration of Fig. 5.

[0147] In particular, as shown in Fig. 6, the fibrillated mesh 100 can be interposed between the medical support structure 200 and the native tissue T of the patient.

[0148] Alternatively, as shown in Fig. 7, the medical support structure 200 can be interposed between the fibrillated mesh 100 and the native tissue T of the patient. As a further alternative, as shown in Fig. 8, a first fibrillated mesh 100 and a second fibrillated mesh 100 can be provided, sandwiching the medical support structure 200.

[0149] In particular, in this configuration, the first fibrillated mesh 100 is arranged between one side of the medical support structure 200 and the native tissue T of the patient, while the second fibrillated mesh 100 is arranged at the opposite side of the medical support structure 200 (Fig. 8).

[0150] According to yet another alternative, as shown in Fig. 9, the fibrillated mesh 100 can be interwoven with the medical support structure 200.

[0151] Conveniently, selection between different arrangements of the at least one fibrillated mesh 100 and the medical support structure 200 (Figs. 6-9) is carried out on a case-by-case basis, in the light of the surgical conditions of the patient.

[0152] Fig. 10 shows a further configuration of the medical implant 300 according to the invention.

[0153] Here, the fibrillated mesh 100 is configured to partially cover the medical support structure 200.

[0154] In particular, the fibrillated mesh 100 may be adapted to cover the medical support structure 200 at its proximal end and / or distal end.

[0155] In particular, in the shown configuration, the fibrillated mesh 100 is adapted to cover the medical support structure 200 at its proximal and distal ends (Fig. 10).

[0156] Figs. 11-14 schematically illustrate respective arrangements of the at least one fibrillated mesh 100 and the medical support structure 200 in the configuration of Fig. 10.

[0157] It may be noted that the arrangements shown in Figs. 11-14 substantially correspond to those of Figs. 6-9, respectively, only differing in that the fibrillated mesh 100 only partially covers the medical support structure 200.

[0158] A further description of the arrangements illustrated in Figs. 11-14 is therefore omitted for the sake of brevity. The medical support structure 200 may comprise a fiber mesh 20, as shown in Fig. 2.

[0159] In the shown embodiment, the medical support structure 200 is an endovascular graft (Fig. 2).

[0160] This is convenient to prevent the occurrence of endoleaks, in particular Type I endoleaks. Alternatively, the medical support structure 200 can be a valve replacement, e.g. a pulmonary valve replacement, an aortic valve replacement, a mitral valve replacement, or a tricuspid valve replacement (not shown),

[0161] As a further alternative, the medical support structure 200 can be a Transcatheter Aortic Valve Implant (TAVI) (not shown).

[0162] This is convenient to prevent the occurrence of paravalvular regurgitation.

[0163] According to yet another alternative, the medical support structure 200 can be Left Atrial Appendage Closure (LAAC) device (not shown). This is convenient to prevent the occurrence of peridevice leaks.

[0164] Still further, the medical support structure 200 can be a Right Atrial Appendage Closure device (not shown).

[0165] According to further alternatives (not shown), the medical structure 200 may as well be one of a stent, a scaffold, a stent graft or a covered stent.

[0166] Also, the medical support structure 200 can be a closure device, e.g. a septum closure device or a vascular closure device, or an occluder, e.g. a Ventricular Septal Defect (VSD) occluder, a Septal occluder, a Patent Foramen Ovale (PFO) occluder, and a Left Atrial Appendage (LAA) occluder (not shown).

[0167] The invention provides medical implant 300 comprising a fibrillated mesh 100 that is specifically designed to facilitate in-situ tissue engineering. Preferably, the medical implant 300 is resorbable in a biological environment. The medical implant 300 provides a scaffold structure that promotes cellular attachment, proliferation, and differentiation at the implantation site. The fibrillated architecture of the mesh is capable of mimicking the natural extracellular matrix, creating an environment conducive to cell infiltration. As the implant material degrades over time, it is progressively replaced by native tissue, supporting the integration and / or formation of functional or non-functional tissue, depending on the application’s specific requirements. This approach relies on endogenous healing mechanisms to enable tissue ingrowth that conforms to the physiological and functional requirements.

[0168] The tissue formation process induced and facilitated by the medical implant 300 of the invention is a multi-phase approach supported by the implant’s structural and biochemical properties, optimized for cardiovascular tissue engineering.

[0169] In particular, the process includes the following steps: 1. Cell Recruitment and Adhesion: Upon implantation of the implant 300, the fibrillated mesh 100, which is characterized by high surface area and porosity, facilitates host cell infiltration, e.g. infiltration of endothelial cells, fibroblasts, and progenitor cells. The fibrillated mesh 100 can be functionalized with biomolecules such as peptides or growth factors to enhance cell adhesion and selectively recruit cell types needed for the desired tissue formation;

[0170] 2. Cell Proliferation and Differentiation: Adhered cells proliferate and spread along the fibrillated structure. The interconnected pores and fibrillar configuration guide cellular migration within the mesh 100, facilitating cell distribution and cell-to-cell interactions. The physiological microenvironment may foster the differentiation of progenitor cells into cardiovascular cell types, including endothelial cells for lining and smooth muscle cells for structural integrity;

[0171] 3. Extracellular Matrix (ECM) Production: As cells proliferate and differentiate, they produce ECM proteins, such as collagen and elastin, progressively replacing the synthetic matrix of the fibrillated mesh 100. ECM deposition strengthens the developing tissue, enhancing its integration with the native tissue;

[0172] 4. Angiogenesis and Vascularization: The structure of the implant 300, and in particular the fibrillated mesh 100, may support angiogenesis by promoting formation of blood vessels within the implant, ensuring nutrient and oxygen supply to the developing tissue. This feature is particularly advantageous in cardiovascular applications, where robust vascularization may be essential for sustaining tissue viability and functionality;

[0173] 5. Controlled Scaffold Resorption: The the implant 300 can be formed of a resorbable material that is specifically engineered to degrade and / or resorb during and / or after tissue formation. As the implant 300 dissolves, it is replaced by native tissue that undergoes natural remodelling and integration into the surrounding tissue, minimizing the need for subsequent implant removal surgeries and reducing foreign body reactions,

[0174] 6. Functional or Non-Functional Tissue Integration: The end result can be integration with surrounding tissue as either functional or non-functional tissue, depending on the desired application. This flexibility enables the implant 300 to adapt to applications requiring either load-bearing, functional tissue or non-functional, structural support, providing durability and the capacity to withstand physiological forces over time. This tissue integration can secure implant fixation and can prevent and overcome leakage of blood at the interface of the medical implant 300 with the native tissue. References

[0175] 100 Fibrillated mesh

[0176] 200 Medical support structure

[0177] 300 Medical implant

[0178] 10 Sponge-like structure (fibrillated mesh)

[0179] 20 Fiber mesh (medical support structure)

[0180] T Native tissue (of a patient)

[0181] C Surface cavity (tissue)

[0182] B Bulging portion (tissue)

Claims

Claims1. A fibrillated mesh (100) for a medical implant (300), said medical implant (300) comprising at least one medical support structure (200), said fibrillated mesh (100) being configured to at least partially cover said medical support structure (200) to facilitate integration of the medical implant (300) with a native tissue (T) of a patient and promote tissue formation.

2. The fibrillated mesh (100) according to claim 1, characterized in that said fibrillated mesh (100) is made of stagged fibers.

3. The fibrillated mesh (100) according to claim 1 or 2, characterized in that said fibrillated mesh (100) has a sponge-like structure.

4. The fibrillated mesh (100) according any one of the preceding claims, characterized in that said fibrillated mesh (100) is resorbable.

5. The fibrillated mesh (100) according to any one of the preceding claims, characterized in that said fibrillated mesh (100) is a fibrillated skirt, preferably a resorbable fibrillated skirt.

6. The fibrillated mesh (100) according to any one of the preceding claims,characterized in that said fibrillated mesh (100) is obtained through one among: electrospinning; electro-spraying; electro-writing; melt-electrospinning, or3D-printing.

7. A medical implant (300) comprising: at least one fibrillated mesh (100) according to claims 1 to 6, and at least one medical support structure (200).

8. The medical implant (300) according to claim 7, characterized in that the fibrillated mesh (100) is configured to entirely cover the medical support structure (200).

9. The medical implant (300) according to claim 7, characterized in that the fibrillated mesh (100) is configured to partially cover the medical support structure (200), preferably wherein the fibrillated mesh (100) is configured to cover the medical support structure (200) at its proximal end and / or distal end.

10. The medical implant (300) according to any one of claims 7 to 9, characterized in that the fibrillated mesh (100) is interposed between the medical support structure (200) and the native tissue (T) of the patient.

11. The medical implant (300) according to any one of claims 7 to 9, characterized in that the medical support structure (200) is interposed between the fibrillated mesh (100) and the native tissue (T) of the patient.

12. The medical implant (300) according to any one of claims 7 to 9, characterized in that the medical support structure (200) is sandwiched between: a first fibrillated mesh (100), arranged between one side of the medical support structure (200) and the native tissue (T) of the patient, and a second fibrillated mesh (100), arranged at the opposite side of the medical support structure (200).

13. The medical implant (300) according to any one of claims 7 to 9, characterized in that the fibrillated mesh (100) is interwoven with the medical support structure (200).

14. The medical implant (300) according to any one of claims 7 to 13, characterized in thatthe medical support structure (200) is one among: an endovascular graft; a pulmonary valve replacement; an aortic valve replacement; a mitral valve replacement; a tricuspid valve replacement; a Transcatheter Aortic Valve Implant (TAVI); a Left Atrial Appendage Closure (LAAC) device; a Right Atrial Appendage Cosure device; a stent; a scaffold; a stent graft, or a covered stent; a septum closure device; a vascular closure device; a duct occluder; a Ventricular Septal Defect (VSD) occluder; a Septal occluder; a Patent Foramen Ovale (PFO) occluder, and a Left Atrial Appendage (LAA) occluder.

15. The medical implant (300) according to any one of claims 7 to 14, characterized in thatthe medical implant (300) is configured for minimally-invasive implantation.

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