Transcatheter antiembolic filter for arterial and venous vessels

Abstract

An intravascular catheter-based filtering device (1) designed to capture and remove emboli, thus preventing distal embolization, comprising: - a tubular filter (2) comprising a flexible porous material and defined by a distal element and a proximal element, i.e. by a main body (3) and a funnel (4); i. the length of said main body (3) is suitable to extend within an appropriate vascular tract; said main body (3) comprises: a) a distal end (5) suitable to be coupled radially with said tract and to seal hermetically to said tract when the device is in active configuration, said distal end (5) being provided with selectively actuatable closing means so that said distal end is designed to open when the device is in active configuration and to close before the device is retracted; b) a proximal end (6); ii. said funnel (4) forms an extension of said main body (3), the base of said funnel being located at said proximal end (6), - a support structure assembly (8) comprising: i. a support catheter (11) extending within said main body (3); ii. one radially expandable distal structure (9) fixed to said distal end (5); iii. one radially expandable proximal structure (10) positioned in correspondence of said proximal end (6), said distal structure (9) and said proximal structure (10) being fixed at least at one end to said support catheter (11).

Description

Technical Field

[0001] The present invention relates generally to a transcatheter antiembolic filter and, more particularly, to an intra-aortic filter for protecting the brain and peripheral vessels from the potential propagation of emboli. Background Art

[0002] Clinical complications of transcatheter heart valve implantation (TAVI) are primarily related to overlap with the diseased native valve. Severe tissue calcification involving the valve device and surrounding tissues impairs proper deployment of the prosthesis, creating conditions for embolic events.

[0003] Procedural embolic events, also known as "macroembolic brain events," occur during the TAVI implantation procedure (before, during implantation, or after dilation). They are primarily related to the embolization of large, calcium-fragmented, fibroelastic particles, typically to the brain (stroke), coronary arteries, or peripheral organs. However, stroke is the most formidable clinical event, currently occurring in 2.7% of patients, compared to 3.3% with previous generations of TAVI. This reduction in stroke is associated with a lower need for pre- and post-dilation procedures during TAVI implantation, but this data is ambiguous as it refers to aortic valves with minimal calcification. Postoperative microembolic brain events were documented in at least 8% of patients investigated. The high incidence of new brain lesions after TAVI warrants long-term assessment of neurocognitive function.

[0004] In this short-term follow-up study of 3 months, no clinical impairment of neurocognitive function was observed, and most lesions (80%) had resolved on MRI at 3 months. However, once the indications for TAVI are expanded to include younger patients with longer life expectancies, the issue of perioperative cerebral embolism and its potential impact on neurocognitive function may portend greater clinical significance.

[0005] Therefore, future research in the field of TAVI should focus on developing strategies to reduce the risk of embolism (eg, less invasive, smaller-bore catheter systems, improved identification of patients at risk for embolism, and the potential use of brain protection devices).

[0006] In some clinical studies, at least 10% of patients undergoing TAVI implantation showed detectable neurologic impairment on psychometric testing. While this rate is acceptable in high-risk and elderly patient populations, it appears unacceptable in lower-risk, younger patients. Several clinical studies are underway to better investigate this clinical situation.

[0007] Another type of embolic event is subacute and chronic microembolic events that occur shortly after surgery. The calcified native aortic valve is rough and warty, immobilizing it like an atherosclerotic plaque. This condition favors the formation of microthrombi, which can subsequently embolize to the brain and other peripheral organs. The presence of a retained native aortic valve as a source of microemboli has been considered in some clinical studies, suggesting a role in the pathogenesis of vascular dementia. This evidence raises concerns when TAVI is implanted in younger patients, as the accelerated development of vascular dementia has significant societal costs.

[0008] In summary, perioperative clinical complications after TAVI implantation are significantly associated with the presence of a severely calcified aortic valve that remains in situ. This leads to acute macroembolic cerebral events (stroke) and hemodynamic consequences, such as the development of PVL with varying degrees of aortic valve dysfunction. These unsatisfactory clinical outcomes are closely related to irregular deployment of the transcatheter valve prosthesis and the highly calcified native aortic valve. Long-term clinical complications are characterized by cerebral microemboli from the retained native aortic valve leaflets, which serve as a source of emboli leading to vascular dementia.

[0009] The overall clinical complication rate of TAVI is between 5% and 12%. This rate is likely an underestimate because it does not include patients with highly calcified and bicuspid native valves.

[0010] These findings highlight the importance of protecting peripheral organs, particularly the brain and heart, to prevent embolism during TAVI.

[0011] The increasing overall utilization of TAVI relative to SAVR and the increasing proportion of intermediate-risk patients undergoing TAVI suggest the desirability of using embolic protection to optimize long-term survival and quality of life in these patients.

[0012] AKI (acute kidney injury) is a common complication after TAVI, with reported rates ranging from 8.3% to 58%. These discrepancies may be partly due to the use of different definitions of AKI. Generally, this complication is related to comorbidities, the route of access (transfemoral, apical, or other), and the amount of contrast agent used during the procedure. There are no clinical studies investigating the association between embolic processes occurring during TAVI and AKI, particularly since no device can directly capture emboli in the renal region. However, it is conceivable that embolic clouds dislodged from the valve during the procedure may contribute to this complication.

[0013] The complications described above with TAVI also apply to other transcatheter procedures, such as valvuloplasty (when not associated with TAVI), native valve repair, and cardiac recovery procedures, all of which can result in the release of emboli from the ventricles, native valves, or thoracic aorta. Furthermore, navigation of the catheter along the calcified aorta can itself dislodge calcifications and release emboli.

[0014] Furthermore, embolic complications have also occurred during transcatheter procedures in addition to intra-aortic procedures, and therefore, antiembolic protection can be strongly recommended in other areas as well.

[0015] In fact, patent applications disclosing embolic protection have been filed for a long time, see for example US patent US 6,361,545, which shows a perfusion filtration catheter that can be employed in SAVR and cardiopulmonary bypass surgery frameworks, or Australian patent application AU 2011202667, which discloses an embolic filtration device and method for heart valve replacement.

[0016] Currently, there are only a few devices in clinical use to protect the brain and peripheral circulation within the framework of transcatheter cardiac and aortic procedures.

[0017] Deflector devices deflect emboli away from the humeral cephalad and left common carotid arteries toward the peripheral circulation: thus, they only prevent fragments from entering the cerebral vasculature and divert them to the peripheral circulation. Furthermore, if they are displaced from their intended location, their diversion function is lost.

[0018] The anti-embolic filter on the market, whose main features are disclosed in US patent application US 2018 / 177582, actually captures emboli with a mesh, but only covers two of the three cerebral blood vessels, not the peripheral circulation.

[0019] Other patents (e.g., U.S. patent applications US 2014 / 0005540 and US 2016 / 0235515) disclose an embolic protection device filter that can protect the brain and systemic circulation, but they present some difficulties in interacting with other working catheters (e.g., the catheter carrying the TAVI device), which need to be positioned before the filter is deployed; in addition, during the TAVI positioning process, a small area of ​​the aorta is not protected because its catheter is outside the protection range of the filter; finally, in the event that TAVI repositioning in the descending aorta is required, the protection of the filter needs to be temporarily removed.

[0020] US Patent Application No. US 2018 / 0110607 discloses an embolic protection device filter capable of protecting the brain and systemic circulation; the device has a collection chamber for embolic capture and confinement while allowing passage of other catheters within its cylindrical body. However, some shortcomings are manifested in the mesh size, which ranges from approximately 1 mm to approximately 0.1 mm, and the lack of a distal closure mechanism that inherently prevents upstream release of embolic blocks during closure.

[0021] International patent application WO 2017 / 042808 discloses an embolic protection device comprising a distal porous deflector covering a cerebral vessel, connected to a proximal embolic collector comprising at least one traversable filter bag. While the distal deflector appears to offer advantages over a full filter configuration in terms of affordability, it exhibits disadvantages when interacting with other active catheters, resulting in a loss of brain protection with even minor deflector movement.

[0022] International patent applications WO 2015 / 185870 and WO 2018 / 211344 both disclose a filtering device comprising a temporary valve prosthesis intended for insertion into the aorta. Both devices offer improvements over other prior art devices. However, they exhibit several drawbacks, such as their proximal location to the native valve, which limits direct access, and the difficulty of inserting other devices through the prosthesis due to catheter size limitations. Summary of the Invention

[0023] As discussed in the previous chapter, the occurrence of clinical events is prevented by the device of the present invention as defined in the claims.

[0024] The device according to the present invention comprises an anti-embolic filter with a proximal funnel that allows a working catheter to pass through a substantially closed filter port while preventing the release of downstream collected emboli. This allows the working catheter of an accessory and / or transcatheter device to be tracked within the filter without direct contact with the vessel, helping to prevent vessel wall damage and associated calcification shedding while also preventing embolic release. Furthermore, the filter includes a distal closure mechanism, which is applied prior to device removal, to prevent the release of upstream emboli during closure. Furthermore, due to the appropriate selection of filter mesh size, protection of the brain and peripheral circulation from both macro- and microembolic emboli is ensured.

[0025] Preferably, the device according to the present invention comprises a transcatheter filter prosthesis for use in a blood vessel, particularly an aortic vessel, comprising a tubular filter and expandable distal and proximal support structures; the tubular filter, when deployed, forms a tubular shape with a generally open distal end and a generally closed proximal port. Full expansion and contraction of the filter is achieved by relative linear movement of an outer shaft relative to an inner support catheter.

[0026] In one specific intra-aortic embodiment, the deployed filter is positioned with its distal end in the ascending aorta (upstream of the innominate artery) and its proximal end in the descending aorta (downstream of the end of the aortic arch).

[0027] In another specific embodiment, the configuration of the funnel can be modified during surgery by maintaining its apex downstream, or returning to an intermediate position within the filter body.

[0028] During surgery, the device can be fully or partially retracted to allow for repositioning. At the conclusion of the procedure, both the distal and proximal closure mechanisms are activated, and the device is retracted, retracted into the shaft, and completely removed from the patient.

[0029] The filtering device is intended to be inserted before starting other transcatheter procedures and removed after other transcatheter devices are removed.

[0030] In summary, the filter device described herein is suitable for ensuring anti-embolic protection, enabling navigation of other working catheters into the filter, permanent closure at the proximal end, and closure at the distal end prior to filter removal, and thus offers advantages over existing devices and methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be better understood with reference to some illustrative embodiments below.

[0032] Figure 1 : A filter device assembly in an active configuration, the assembly comprising a filter-structure-conduit assembly (12), an outer shaft (13), and a handle (16);

[0033] Figure 1a :Terminology for filter device components;

[0034] Figure 1b : Body of the filter (3): Some geometrical examples (a) cylindrical, b) conical, c) cylindrical-conical, d) biconical, e) polygonal;

[0035] Figure 1c: Support structure assembly embodiment (8);

[0036] Figure 2 : Example of two distal ring structure implementation (9b) in active configuration;

[0037] Figure 2a : Adaptability mechanism of two distal ring structure implementations;

[0038] Figure 2b : Retraction mechanism of two distal ring structure embodiments;

[0039] Figure 3 : An example of a distal ring structure implementation (9a) in an active configuration;

[0040] Figure 3a : An adaptable mechanism for implementing a distal ring structure;

[0041] Figure 3b : A retraction mechanism of a distal ring structure embodiment;

[0042] Figure 4 : A movable proximal funnel embodiment (4);

[0043] Figure 4a : movable funnel in inactive configuration (funnel downstream);

[0044] Figure 4b : movable funnel in active configuration (funnel re-enters the main body);

[0045] Figure 5 : An example of a fixed funnel embodiment (4) with an "8"-shaped proximal end structure (10);

[0046] Figure 6 : An embodiment of a fixed funnel (4) having a ring-shaped proximal end structure (10);

[0047] Figure 7a : Example of distal closure mechanism (15);

[0048] Figure 7b : Example of proximal closure mechanism (14);

[0049] Figure 8: Ring configuration example;

[0050] Figure 9: Integration of the distal structure (9b) and the movement mechanism of the funnel (4);

[0051] Figure 10: Example of trackability and navigation tools: outer shaft (13), radiopaque marker (19), and tip (17);

[0052] Figure 11a to Figure 11g : Methods of Embolic Protection: An Intra-Aortic Procedure Example;

[0053] Figure 11a : Ascending aorta with guidewire (29);

[0054] Figure 11b : Navigation of a telescopic filtering device (1) along the aortic arch (25);

[0055] Figure 11c: The device is deployed at the predetermined position;

[0056] Figure 11d: Interaction between the device, pigtail and other working conduits (31);

[0057] Figure 11e : Embolic entrapment and direction of blood flow through the device;

[0058] Figure 11f: Activation of the proximal (14) and distal closure (15);

[0059] Figure 11g: The filter device was removed after surgery;

[0060] Figures 12a to 12d : Examples of different filters with a funnel configuration defined by one or more suture lines.

[0061] Reference numerals used in the drawings

[0062] Device-related items

[0063] 1 Transcatheter filtration device

[0064] 2 Tubular filters

[0065] 3 Tubular filter body

[0066] 4 Funnel

[0067] 5 Distal end of tubular filter

[0068] 6 Proximal end of tubular filter

[0069] 7 Tubular filter port (matches the top of the funnel)

[0070] 8 Structural components

[0071] 9 Distal structures

[0072] a. Implementation with one ring

[0073] b. Embodiment with two rings

[0074] 10 Proximal structures

[0075] 11 Support catheter

[0076] 12 Filter-Structure-Catheter Assembly

[0077] 13 external axis

[0078] 14 Proximal Closure System

[0079] a. Self-sealing automatic closing mechanism (aa; ab: two different implementation methods)

[0080] b. Mechanical closing mechanism (b1 open; b2 closed)

[0081] 15 Distal Closure System

[0082] 16. Handles and associated commands. These commands may include the following:

[0083] a. Command for movement of the outer shaft (13)

[0084] b. Command for trimming the distal structure (9)

[0085] c. Command post for funnel (4) movement

[0086] d. Command for activating the proximal port (7)

[0087] e. Command for activating remote port (7)

[0088] f. Flush port for guidewire (29)

[0089] g. Flushing port for outer shaft (13)

[0090] 17 Tip

[0091] 18 Prosthetic valves

[0092] 19 Radiopaque markers

[0093] Anatomical reference symbols

[0094] 20 Aortic valve

[0095] 21 Coronary artery ostium

[0096] 22 Sinotubular junction

[0097] 23 Ascending aorta

[0098] 24 Innominate artery

[0099] 25 Aortic arch

[0100] 26 Descending aorta

[0101] 27 Femoral access

[0102] Working tubes and other accessories

[0103] 28 Introducer

[0104] 29 Guidewire

[0105] 30 pigtails

[0106] 31 Working catheter

[0107] 32 Subfunnel suture

[0108] 33 Sutura suprafugal

[0109] 34 Intermediate structure (Example A)

[0110] 35 Intermediate Structure (Example B) DETAILED DESCRIPTION

[0111] In one embodiment, the anti-embolic filter device comprises the following macroscopic elements ( Figure 1 ): component 12, which includes a tubular filter 2 suitable for retaining emboli while allowing blood flow; a structural component 8, which is used to support the filter and connect the filter to the blood vessel; an outer shaft 13, which is used to retract / track / expand / remove the component; and a handle 16, which is used to utilize specific commands to achieve the operation and optimal sealing with the blood vessel and interaction with other devices.

[0112] like Figure 1 As shown in FIG, the tubular filter 2 is placed outside the structural assembly 8: the assembly includes a distal support structure 9, which is placed upstream relative to the direction of blood flow and is intended to connect the filter to the blood vessel without leaking; a proximal support structure 10, which defines an area for collecting emboli and other devices passing through the area inside the filter by passing through the relevant port 7; and a support conduit 11, as shown in FIG. Figure 1c In a specific embodiment, the tubular filter 2, structural assembly 8, outer shaft 13 and handle 16 are permanently connected.

[0113] In a specific embodiment ( Figure 2 、 3 ), the filtering device is suitable for use as a protective device within the aorta, extending from the ascending aorta 23 upstream relative to the innominate artery 24 to the descending aorta 26.

[0114] Figure 1a The main components of the filtering device 1 described below are shown, starting with the tubular filter 2 component, then the structure 8, the shaft 13, and the handle 16.

[0115] The tubular filter 2 is preferably made of a low-friction porous flexible polymeric material or composite material, including polyester or polyamide, and its mesh size is preferably less than 150 microns. It can be coated with a hydrophilic coating, a low-friction coating or an anti-thrombotic coating or a combination thereof. The filter material, coating and shape are conducive to the navigation of the catheter device in the body during insertion and removal, preventing direct contact with the blood vessel wall, which can damage the blood vessel wall. Specific embodiments include perforated membranes and fabrics. In one embodiment, a woven fabric can be selected, whose warp and weft are made of multifilament or monofilament yarns, with a constant or variable weaving pattern, thereby producing holes composed of square and circular geometric shapes, and also producing constant or variable mesh size and opening area along the longitudinal and circumferential directions of the filter.

[0116] The tubular filter 2 is geometrically defined by a distal element and a proximal element, namely a body 3 and a funnel 4 ( Figure 1a The body 3 comprises a distal end 5 and a proximal end 6; the distal end 5 is adapted to be opened when the device is in an active configuration, to be airtightly connected to the blood vessel, and to be closed before the device is retracted; the proximal end 6 is adapted to be opened when the device is in an active configuration; the funnel 4 forms an extension of the body 3, with the base of the funnel being located at the proximal end (6).

[0117] Filter body 3 ( Figure 1 ) includes cylindrical, conical and combinations thereof. Specific embodiments for intra-aortic surgery include a three-zone body 3e ( Figure 1b ), which has a distal cylindrical portion 3-1 that connects to the aorta, a mid-conical portion 3-2 with a gradually decreasing diameter, and a proximal cylindrical portion 3-3. The mid-section is shaped to reduce the associated pressure drop in blood circulation and the burden on the integral filter along the inner side of the aortic arch 25; the geometry of the proximal cylindrical portion is intended to allow free forward and backward movement of the working catheter, even in the case of a partially retracted TAVI procedure after removal from the descending aorta. The main body is generally 10 to 30 centimeters in length to accommodate the entire length of the blood vessel to be protected, extending from the ascending aorta 23 (upstream relative to the innominate artery 24) to the descending aorta 26.

[0118] Embodiments of the funnel 4 include movable and fixed funnels, having symmetrical or asymmetrical shapes.

[0119] Figure 4 One embodiment of the movable funnel 4 is shown, the funnel being in its extreme configurations: a first position (see Figure 4b ), wherein the funnel apex is proximal relative to the proximal opening end 6 of the main body 3, the second position (see Figure 4a), wherein the funnel apex is located within the body, between the distal and proximal ends of the body 3. In the active configuration, the funnel top is generally located within the body, thereby acting as a sliding conveyor for the working catheter to pass through, while simultaneously collecting emboli in the space between the body and the funnel 4c, which makes the interaction between the working catheter and the funnel port essentially embolism-free. In this embodiment, the funnel is oriented by acting on the apex, i.e., using a push-pull system directed by a handle, such as Figure 4b and Figure 4a As shown in detail in , this embodiment allows the funnel to move as the working conduit passes through it.

[0120] The second implementation of the funnel ( Figure 5 ) comprises a fixed funnel element having a distal apex 4-2 which enables the passage of the working conduit, connected to the following elements: on the lateral side, connected to a fixed conical element which is the proximal part of the main body 3 and has a proximal apex 4-1 suitable for collecting emboli; connected to a proximal ring 10 which has the shape of an "8" and defines the base of the funnel and the collecting conical element; connected to a flap 4-3 whose distal base is connected to the filter body 3 or the support conduit 11 and whose proximal end is connected at least at one point to the funnel 4-2, the flap being suitable for preventing the release of emboli downstream while allowing the passage of the funnel.

[0121] In the third embodiment of the funnel ( Figure 6 ), which comprises a funnel element of fixed orientation, the base of which is open at the proximal end in the active configuration, acting as a transmitter; the funnel is connected to at least the following elements: on the lateral side, to a fixed conical element, which is the proximal part of the body 3, the apex of which is closed at the proximal end; to a radially expandable proximal structure (10), which can be manually activated or self-expanding.

[0122] The funnel element is typically located in a straight portion of the vessel to ensure easy passage of the working catheter through its apex. The funnel is shorter than the main body, with the ratio of funnel to main body length typically ranging from 1 / 10 to 1 / 3, depending on the specific vessel centerline length, shape, and vessel diameter. In specific intra-aortic embodiments, the funnel length is typically between 2 and 10 centimeters.

[0123] A proximal closure system 14 preventing downstream embolic release is located at the apex of the funnel 4, known as the filter proximal port 7: it can be constituted by a funnel geometry so as to orient the apex downstream with respect to the blood flow, or by a folded top or a combination of systems thereof, or by an actual closure system; one embodiment of the closure system is constructed by a lazoo system activated by a wire, which can be activated manually 14b or automatically 14a thanks to an elastic wire. Figure 7bAn embodiment of a proximal port applied to a movable funnel system is shown: in the top two pictures the mechanical closure mechanism is shown in the open position b1 and in the closed position b2, while in the bottom two pictures two different self-sealing automatic closure embodiments aa; ab are shown.

[0124] The distal closure system 15 is used to prevent upstream displacement at the end of the procedure and is activated before re-expansion of the device ( Figure 7a ), which can be a manually activated lazoo system or an automatic elastic system that is manually deactivated in an active configuration.

[0125] Figure 1c A specific embodiment of the support structure assembly 8 is shown in the figure; it includes at least: a support catheter 11 extending within the main body; a radially expandable distal structure 9 connected to the distal end of the main body; a radially expandable proximal structure 10 located at the proximal end level of the main body, and the distal structure 9 and the proximal structure 10 are fixed to the support catheter 11.

[0126] Figure 2 and Figure 3 Two embodiments of the filter device 1 in an active configuration are shown, differing in the elements of the distal structure 9. In both cases, the mechanical stability of the filter device, whether in a stand-alone state or when traversed by other working catheters, is ensured at least by the connection of the distal structure 9 to the ascending aorta and the connection of the support catheter 11 to the aortic arch.

[0127] The radially expandable nature of the distal structure ensures coverage of a wide range of geometries (ascending aorta diameter typically ranges from 20 to 40 mm) and anatomies, with reduced size of the filtering device without risk of device displacement or migration.

[0128] exist Figure 2 In the specific embodiment shown in , the distal end 9 structure includes two annular elements 9b, referred to herein as the more proximal element and the more distal element, which are connected to each other: the more distal annular element is connected to the catheter 11 at its distal end and to the more proximal annular element at its proximal end, and is also connected to the distal end of the body 3 along its periphery; the more proximal element is connected to a specific handle sealing command at its proximal end via a rod, passing through the lumen of the supporting catheter 11. This structure can be composed of a single wire or multiple wires, and the cross-section of the wire can be circular, oval, rectangular, or a combination thereof; the connection between the components can be formed by crimping, welding, gluing, bundling, or in the case of wire elements, by twisting them, or by using a combination thereof.

[0129] The distal annular element is designed to expand radially conforming to the aorta in an active configuration, thereby ensuring a leak-free connection: this is ensured by the high elastic limit of the material used (preferably but not limited to Nitinol), its geometry (circumference larger than the aortic vessel), the relative free orientation of the axis (tilted relative to the aortic centerline), and the relative deformation mechanism commanded by the handle. For example, by actively pushing on the sealing handle command (moving forward on the command 16b: Figure 2a ), pushing the proximal annular element onto the distal annular element, thereby tilting the relevant annular plane portion, resulting in radial compression on the aortic wall. In this embodiment, the handle command portion can be pulled (moved backward on the command portion 16b: Figure 2b ) to close the distal end of the filter body without using a specific command. Figure 9 In a further specific configuration shown in , the interconnection between the distal ring and the funnel command portion can simultaneously act on the closure mechanism of the distal end of the filter and the movement of the funnel apex, thereby simplifying the handle mechanism and the operations to be performed before device removal.

[0130] exist Figure 3 In the embodiment shown in FIG, the distal end 9 structure comprises a ring element 9a, the proximal end of which is connected to the catheter 11, the periphery of which is connected at the distal end of the body 3, the distal end of which is connected to a single or multiple wires passing through the interior of the filter and connected to a specific handle sealing command. In this case, the radial expansion of the ring is ensured by a pulling system instead of a pushing system command ( Figure 3a ), for the radial expansion of the ring, an analogy is applied Figure 2a Considerations for distal annular elements mentioned in.

[0131] Figure 4 FIGURE 1 shows a specific embodiment of a proximal structure 10, which is annular in shape and is connected to a support catheter. This ring defines the base of the funnel 4 and allows its apex to be tilted proximally and distally by means of specific commands connected to the handle. In the illustrated embodiment, the ring does not couple to the descending aorta. In other embodiments, the proximal structure 10 can be shaped similarly to the distal structure 9, thereby allowing for radial coupling to the aortic vessel.

[0132] Specific embodiments may be constructed in which intermediate structures relative to the distal end 9 and the proximal end 10 may be connected to a support conduit 11 to increase the stability of the device and to facilitate full expansion of the tubular filter body.

[0133] For both the distal and proximal structures and applicable intermediate structures, the overall geometric shape may be elliptical in plan view, but may also be a different shape, e.g. Figure 8Similarly, the transverse view can show a planar structure, but can also be an "S" shaped transverse profile to enhance leak-free conformity to the aortic arch, as shown in FIG. Figure 8 As shown in .

[0134] The support catheter 11 is connected to the distal 9 and proximal 10 structures and the tubular filter 2, and in the active configuration adapts to the extrados of the aortic arch and bears all the loads generated by the operation (see Figures 11a-11g ): To this end, it can be made of a flexible polymer or composite material, here including a metal braided polymer, selected as an optimal compromise between high elongation / compression / torsion stiffness and considerable flexibility. The contour of the support catheter 11 is adapted to accommodate, within a specific lumen, the command for compressing / deploying the filter 2, acting, where applicable, on the distal 9 and proximal 10 structures and the distal and proximal filter closure systems, and accommodating other accessories / working catheters, here including a guidewire, pigtail and balloon catheter, which helps to simplify the entire procedure.

[0135] Outer shaft 13 (see Figure 10 and 11a -11g) is adapted to guide the telescopic filter assembly 12 into position and allow deployment / retrieval of the device by sliding it posteriorly and anteriorly relative to the multi-lumen catheter. The outer shaft 13 is made of a flexible polymer or composite material, preferably a polymer braided with metal, that has low tensile and compressive elongation and sufficient flexural conformability to ensure optimal pushability when tracking the filtering device along the aortic arch, thereby allowing it to conform to the lateral curvature of the aorta without forcing itself thereon and minimizing entrapment when interacting with the support catheter to compress / deploy the filter.

[0136] A tip 17 may be included in any of the structures 9, 11 or the outer shaft 13 or other structures to allow for sufficient excitation effect to facilitate the introduction of the guide through and smooth navigation into the aorta ( Figure 2 and Figure 10 ).

[0137] Radiopaque marker 19 (see Figure 10 、 Figure 11b details in the accompanying drawings) can be attached to specific locations 11, 13, 9, 10 or other structures to facilitate positioning of the device (1) and other working catheters intended to traverse it through adequate imaging.

[0138] Handle 16 ( Figure 1a) Allows for specific commands, including sliding movement between the outer shaft 13 and support catheter 11, where applicable, to allow for filter compression or deployment 16a, activation of the distal closure mechanism 16e, activation of the closure mechanisms at the proximal ends 14, 16d, and distal ends 15, 16e, tensioning of the distal support structure 9, 16b, funnel movement 16c, flushing of the guidewire port 16f and the outer shaft port 16g, direct loading of other devices or accessories (not limited to guidewires and / or pigtail catheters), and, where applicable, activation / deactivation of the prosthetic valve 18. The handle structure is preferably, but not limited to, a polymer material; it houses all commands, made of rods or wires, as well as the support catheter 11 and the proximal end of the outer shaft 13, either directly or through a metal tube. The handle may incorporate linear / rotational mechanisms to allow for the described movement and, where applicable, the occlusion system to secure it in a defined position.

[0139] The following will describe in detail transcatheter procedures using the anti-embolic filter device 1 , with particular reference to intra-aortic procedures (including TAVI herein), which allow for cerebral and systemic embolic protection.

[0140] In this embodiment, access to the anti-embolic filter device 1 is made from the (secondary) femoral artery opposite the (aorta) through which the working catheter 31 of the device for prosthetic or therapeutic aortic valve is introduced. Figure 11d The following are the details of the relevant surgery:

[0141] a) The guide 28 is inserted into the femoral passage 27;

[0142] b) Insert the guidewire 29 into the introducer 28 and navigate to the aortic arch ( Figure 11a As an option, a pigtail is inserted and navigated up to the ascending aorta for fluoroscopic reference before insertion of the filter device;

[0143] c) Before introducing the filter device into the arterial blood vessel, it is expanded, infused and bubbled into the outer shaft catheter 13 ( Figure 11b );

[0144] d) With the aid of radiopaque markers and appropriate imaging techniques, the device is tracked along the vessel and positioned upstream of the innominate artery 24; the device is deployed and connected to the ascending aorta by retracting the outer shaft catheter 13 ( Figure 11c );

[0145] e) When the device is deployed, the distal end of the filter 5 conforms to the aortic wall, thereby conveying all blood and possible debris into its funnel ( Figure 11e ), thanks to the support structure 9, which pushes the distal filter surface 5 circumferentially towards the aortic wall;

[0146] f) Other working conduits can now be introduced into the filter by passing through funnel 4, while the configuration of funnel 4 and port 7 prevents debris from being displaced forward. Figure 11d Shows the interaction between the filter device and other working catheters commonly used in TAVI surgery;

[0147] g) At the conclusion of the procedure, the distal end of the filter 5 (which remains open in the expanded configuration) can be sealed before the device is re-expanded to prevent upstream displacement of any debris from emboli collected at the proximal end of the device ( Figure 11f );

[0148] h) If Figure 11g As shown in FIG, the device is fully re-expanded by pushing the outer shaft catheter 13 distally. In this way, the device structure gradually expands and contracts until it reaches the distal end of the device, safely retaining any captured blood clots or calcium fragments.

[0149] i) Finally, remove the entire device.

[0150] Specific procedures may require partial closure, repositioning, and redeployment at different levels (e.g., from the sinotubular junction to the descending aorta), ultimately requiring different support catheter positioning.

[0151] Furthermore, procedures other than intra-aortic procedures may require different geometric arrangements of the above concepts, so this filter device can in principle be applied in any arterial or venous system where anti-embolic protection is required.

[0152] This approach allows the deployment of the filter device prior to the other working conduits 31 (see Figure 11d ), and remove it after all other working catheters, thus being able to:

[0153] a) Collect and retain emboli released during transcatheter procedures, with the working device eventually moving along the filter;

[0154] b) tracking the working catheter within the filter without direct contact with the vessel wall;

[0155] c) The proximal port 14 of the filter is normally closed throughout the procedure, while the distal port 15 is closed until the filter device is retracted and removed, thereby preventing any downstream and upstream embolic release ( Figure 11f ).

[0156] Figures 12a to 12d The funnel 4 is shown, along with different configurations of dead ends for capturing emboli generated during surgery. Figure 12aThe middle funnel 4 is delimited by two sutures 32, 33 connecting the two walls of the tubular filter 2. In particular, the upper suture 33 runs along the catheter body 11. The space between the upper suture 33 and the stent 11 is dedicated to the distal structure 9b.

[0157] In another embodiment ( Figure 12b ), the boundary of funnel 4 and Figure 12a The tubular filter 2 is the same as in the embodiment of FIG. 1 , but further comprises an intermediate structure 34 for capturing emboli. The intermediate structure 34 has a conical shape and is defined between the two sutures 32′ and 32″. The base of the cone is located at the distal end and forms an embolic inflow port composed of a rigid ring.

[0158] Figure 12c Describes the Figure 12a A similar solution, where the distal end of the funnel 4 is a rigid ring 7 .

[0159] exist Figure 12d In the embodiment, the tubular filter 2 comprises an "8"-shaped element consisting of two rigid rings, wherein the upper ring 7 forms the distal end port of the funnel 4 and the lower ring forms the base of the intermediate structure 35 for embolic capture.

Claims

1. An intravascular transcatheter filtering device (1) designed to capture and remove emboli, thereby preventing distal embolism, the filtering device comprising: - a tubular filter (2) comprising a flexible porous material and defined by a distal element and a proximal element, comprising a body (3) and a funnel (4); i. The length of the main body (3) is suitable for extending within an appropriate vascular zone; the main body (3) comprises: a) a distal end (5) adapted to be radially coupled to the zone and hermetically sealed to the zone when the filtering device is in the active configuration, the distal end (5) being provided with selectively actuatable closing means so that the distal end is designed to open when the filtering device is in the active configuration and to close before the filtering device is retracted; b) proximal end (6); ii. the funnel (4) forms an extension of the body (3), the base of the funnel being located at the proximal end (6), and - a supporting structure assembly (8), said supporting structure assembly comprising: i. a support conduit (11) extending within the body (3), the support conduit being a tubular body extending completely through the body from the proximal end of the body to the distal end of the body; ii. a radially expandable distal structure (9) fixed to the distal end (5); iii. a radially expandable proximal structure (10), said proximal structure being positioned corresponding to said proximal end (6), It is characterized in that the supporting catheter (11) is directly attached to the radially expandable distal structure (9) and the radially expandable proximal structure (10).

2. The device according to claim 1, wherein The funnel (4) is fixed relative to the body (3) between the distal end (5) and the proximal end (6), and the top of the funnel is located inside the body (3).

3. The device according to claim 1, wherein The porosity of the flexible porous material of the filter (2) is less than 150 microns.

4. The device according to claim 1, wherein The proximal end (6) is provided with a selectively actuatable closing mechanism.

5. The device according to claim 1, wherein The filter is made of a low friction and flexible polymer, or a low friction and flexible composite material.

6. The device according to claim 1, wherein The filter is coated with a hydrophilic coating, a low friction coating, or an anti-thrombotic coating, or a combination thereof.

7. The device according to claim 1, wherein The distal structure (9) and the proximal structure (10) have an annular shape.

8. The device according to claim 7, wherein At least one of the distal structure (9) and the proximal structure (10) comprises two rings connected to each other.

9. The device according to claim 1, wherein The apex of the funnel (4) is provided with a catheter access port, so that the funnel (4) is designed to act as a conveyor for a working catheter to pass through it.

10. The device according to claim 1, wherein The support catheter (11) is suitable for tracking other working catheters or instruments in the relevant cavity while allowing embolism to be retained.

11. The device according to claim 1, wherein The geometry of the filter device is suitable for intravascular surgery, and the length of the filter body is suitable for extending within an appropriate vascular zone, including between 10 cm and 30 cm for intra-aortic surgery, so as to be suitable for extending from the ascending aorta (23) to the descending aorta (26).

12. The device according to claim 1, comprising an artificial valve (18).

13. The device according to claim 1, comprising an intermediate structure (34, 35) comprising a dead end, said intermediate structure (34, 35) being adapted to capture emboli transported by the blood flow.

14. The device according to claim 1, wherein The tubular filter (2) comprises one or several sutures defining specific areas including the funnel (4), the intermediate structure (34, 35) with a dead end or the passage for the distal structure (9).

15. The device according to claim 1, wherein The porosity of the flexible porous material of the filter (2) is between 40 and 70 microns.

16. The device according to claim 1, wherein The support conduit (11) is connected to the tubular filter (2).

17. The device according to claim 16, wherein The funnel (4) is fixed relative to the body (3) between the distal end (5) and the proximal end (6), and the top of the funnel is located inside the body (3).

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