Left atrial appendage closure device

Abstract

The present application relates to a left atrial appendage occluder, comprising: an expandable frame transitionable between a compressed state and an expanded state; a covering membrane arranged along at least part of the outer surface of the expandable frame; a connecting structure arranged at the proximal end of the expandable frame and being connectable to and disconnectable from a conveying system; and an anticoagulant coating arranged only on at least part of the outer surface of the covering membrane. The present application can reduce the risk of thrombus formation on the surface of the left atrial appendage occluder and accelerate the endothelialization process.

Description

Left atrial appendage closure device TECHNICAL FIELD

[0001] The present application relates to the field of medical devices, in particular to a left atrial appendage closure device with an anticoagulant composite coating. BACKGROUND

[0002] Atrial fibrillation (AF) is a common arrhythmia in clinical practice, and thromboembolism is the main cause of death in patients with AF. Clinical data shows that more than 90% of thrombosis in patients with AF is related to the left atrial appendage. At present, left atrial appendage occlusion has become a mature method to prevent thromboembolism.

[0003] After the implantation of the left atrial appendage occluder, at least 4-6 weeks are needed for endothelialization, so during this process, continuous anticoagulant therapy is needed, and coating an anticoagulant coating on the surface of the left atrial appendage occluder can effectively reduce the risk of blood clotting and reduce the risk of some complications. Among the many complications of left atrial appendage occlusion, thrombus formation on the surface of the occluder is a very common complication in the long term after the operation, and the reasons are complex and diverse, related to the patient's own coagulation disease, postoperative anticoagulant drug situation, the shape of the left atrial appendage and the occlusion situation of the occluder, and many other factors, and after falling off, it has a very high embolism risk. Therefore, the formation of thrombus seriously affects the safety of the use of the device, and the anticoagulant treatment of the device surface in contact with blood for a long time is very necessary.

[0004] However, the main strategy for dealing with the problem of anticoagulant treatment in clinical practice at present is to use antibiotics and anticoagulants for auxiliary treatment through systemic administration, but long-term use of antibiotics and anticoagulants will inevitably cause a series of side effects, such as antibiotic resistance and thrombocytopenia, and even bleeding. Therefore, the best way is to directly set an anticoagulant coating on the surface of the device. However, the existing heparin coating is mainly used for anticoagulation, and the heparin coating is combined to the surface of the device in a chemical grafting manner, which involves surface modification, complex process, repeated surface pretreatment, and toxic chemical reagents, etc. The safety is questionable, especially the coating is easy to fall off and cannot maintain long-term anticoagulant effect.

[0005] It should be noted that the information disclosed in the background section of this application is only intended to deepen the understanding of the general background of the present application, and should not be regarded as acknowledging or implying in any form that the information constitutes prior art known to those skilled in the art. SUMMARY

[0006] Therefore, the purpose of the present application is to provide a left atrial appendage closure device which can effectively reduce the risk of thrombus formation on the surface of the device, accelerate the endothelialization process, and solve the common problem of blood clotting on the surface of medical devices in the prior art.

[0007] According to a first aspect, the application provides a left atrial appendage closure device, comprising: a frame; a covering film arranged along at least a portion of an outer surface of the frame; and an anticoagulant composite coating arranged on at least a portion of an outer surface of the covering film; the anticoagulant composite coating comprises a first adhesive layer and a second anticoagulant layer arranged from inside to outside along the thickness direction of the covering film, and the first adhesive layer comprises an amphiphilic polymer.

[0008] Optionally, the covering film comprises a fiber bundle comprising a plurality of fiber filaments, and the anticoagulant composite coating is arranged on the surface exposed by the outer fiber filaments in the fiber bundle and the gap between the outer fiber filaments.

[0009] Optionally, the material of the covering film is at least one of polyethylene, polypropylene, polyester, polyurethane, and polyethylene terephthalate.

[0010] Optionally, the pore size of the covering film is 50 μm to 300 μm.

[0011] Optionally, the first adhesive layer comprises at least one of polyamide, polycarbonate, polydimethylsiloxane, polycaprolactone, methyl cellulose, ethyl cellulose, and polybutylene adipate / terephthalate.

[0012] Optionally, the thickness of the first adhesive layer is not more than 0.1 μm.

[0013] Optionally, the second anticoagulant layer has at least one of the following characteristics:

[0014] The thickness of the second anticoagulant layer is not more than 1 μm;

[0015] The surface contact angle of the second anticoagulant layer is 100° to 130°;

[0016] The second anticoagulant layer comprises a fluorine-containing polymer.

[0017] Optionally, the second anticoagulant layer comprises at least one of polytetrafluoroethylene, polyvinylidene fluoride, fluorinated ethylene propylene copolymer, and polyvinylidene fluoride-hexafluoropropylene copolymer.

[0018] Optionally, further comprising a connecting structure arranged at the proximal end of the frame and used for releasable connection with a delivery system; the surface of the connecting structure and the surface of the frame are not provided with the anticoagulant composite coating.

[0019] And / or, the covering film has a proximal portion and a distal portion arranged in an axial direction from a proximal end to a distal end of the frame, the proximal portion extends from the proximal end of the frame and covers to a maximum outer diameter of the frame, and the anti-coagulation composite coating is arranged on an entire outer surface of the proximal portion and extends beyond the maximum outer diameter of the frame.

[0020] Optionally, the covering film is configured to arrange the anti-coagulation composite coating only on at least a portion of an outer surface thereof, and the covering film is further configured to be a non-anti-coagulation region on other surfaces except the surface arranged with the anti-coagulation composite coating.

[0021] The left atrial appendage closure device provided above comprises: a frame; a covering film arranged along at least a portion of an outer surface of the frame; and an anti-coagulation composite coating arranged on at least a portion of an outer surface of the covering film; the anti-coagulation composite coating comprises a first adhesive layer and a second anti-coagulation layer arranged in a thickness direction of the covering film from inside to outside, and the first adhesive layer comprises an amphiphilic polymer.

[0022] In this way, because the anti-coagulation composite coating containing the second anti-coagulation layer is arranged on the outer surface of the covering film, the surface of the covering film can play an anti-coagulation role through the second anti-coagulation layer, thereby reducing the risk of thrombosis on the surface of the device and accelerating the process of endothelialization. In addition, because the first adhesive layer has both hydrophilic and hydrophobic properties, it can be better combined with the covering film and the second anti-coagulation layer, thereby increasing the firmness of the entire coating, reducing the risk of coating falling off, and maintaining long-term anti-coagulation effect. In addition, because the anti-coagulation composite coating is combined with the surface of the covering film in a physical coating manner, the process is simple and safe.

[0023] According to a second aspect, the present application further provides another left atrial appendage closure device, which comprises:

[0024] An expandable frame capable of converting between a compressed state and an expanded state;

[0025] A covering film arranged along at least a portion of an outer surface of the expandable frame;

[0026] A connecting structure arranged at a proximal end of the expandable frame and capable of being connected and disconnected with a delivery system; and

[0027] An anti-coagulation coating covering only at least a portion of an outer surface of the covering film.

[0028] Optionally, the covering film comprises a fiber bundle comprising at least one fiber filament, and the anti-coagulation coating covers the surface exposed by the outer fiber filament in the fiber bundle and the gap between the outer fiber filament and the fiber filament.

[0029] Optionally, the material of the film is at least one of polyethylene, polypropylene, polyester, polyurethane, polyethylene terephthalate.

[0030] Optionally, the pore size of the film is 50 μm to 300 μm.

[0031] Optionally, the film has a non-anticoagulation region in addition to the region covered by the anticoagulation coating, the non-anticoagulation region including a non-anticoagulation coating and / or a portion of the film exposed, the non-anticoagulation coating being less hydrophobic than the film.

[0032] Optionally, the non-anticoagulation coating has at least one of the following characteristics:

[0033] The non-anticoagulation coating includes at least one of polyacrylamide, polyvinyl alcohol, polyvinylpyrrolidone, polyetherimide, polyester, polyurethane.

[0034] The thickness of the non-anticoagulation coating is less than or equal to 0.1 μm.

[0035] The surface contact angle of the non-anticoagulation coating is 45° to 90°.

[0036] Optionally, the anticoagulation coating has at least one of the following characteristics:

[0037] The anticoagulation coating is more hydrophobic than the film.

[0038] The thickness of the anticoagulation coating is less than or equal to 1 μm.

[0039] The surface contact angle of the anticoagulation coating is 100° to 130°.

[0040] The friction coefficient of the anticoagulation coating is less than that of the non-anticoagulation region on the film.

[0041] The anticoagulation coating includes a fluorine-containing polymer.

[0042] Optionally, the anticoagulation coating includes at least one of polytetrafluoroethylene, polyvinylidene fluoride, fluorinated ethylene propylene copolymer, polyvinylidene fluoride and hexafluoropropylene copolymer.

[0043] Optionally, the fluorine content of the anticoagulation coating is 8 to 80 μg / cm 2 , and / or the friction coefficient of the fluorine-containing polymer is not more than 0.1.

[0044] Optionally, the surface of the connection structure and the surface of the expandable frame are not provided with the anti-coagulation coating, and / or the covering membrane has a proximal portion and a distal portion arranged in an axial direction from the proximal end to the distal end of the expandable frame, the proximal portion extends from the proximal end of the expandable frame and covers the position of the maximum outer diameter of the expandable frame, and the anti-coagulation coating covers the entire outer surface of the proximal portion and extends beyond the maximum outer diameter of the expandable frame.

[0045] The left atrial appendage occluder provided by the present application has at least the following beneficial effects:

[0046] The left atrial appendage occluder provided by the present application has at least the following beneficial effects:

[0047] In this way, on the one hand, the anti-coagulation coating provided on at least a portion of the outer surface of the covering membrane can effectively inhibit the formation of thrombus, thereby accelerating the process of endothelialization; on the other hand, the hydrophobic surface provided by the anti-coagulation coating can also effectively avoid tissue adhesion during implantation, improve operability, and reduce damage caused by operation. BRIEF DESCRIPTION OF DRAWINGS

[0048] Those skilled in the art will understand that the provided drawings are for better understanding of the present application and do not constitute any limitation on the scope of the present application. Among them:

[0049] FIG. 1 is a structural schematic view of the left atrial appendage occlusion device according to an embodiment of the present application, and the connection structure at the proximal end is highlighted in detail A;

[0050] FIG. 2 is a structural schematic view of the anti-coagulation composite coating provided on at least a portion of the outer surface of the covering membrane according to an embodiment of the present application;

[0051] FIG. 3 is a schematic view of the braided mesh covering membrane with an anti-coagulation composite coating and the cross section of the fiber bundle according to an embodiment of the present application;

[0052] FIG. 4 is a cross-sectional view of the fiber bundle according to an embodiment of the present application;

[0053] FIG. 5 is a structural schematic view of the left atrial appendage occluder according to an embodiment of the present application;

[0054] FIG. 6 is a structural schematic view of the left atrial appendage occluder according to an embodiment of the present application;

[0055] Fig. 7 is a structural schematic diagram of the left atrial appendage occluder according to the third embodiment of the present application;

[0056] Fig. 8 is a structural schematic diagram of the left atrial appendage occluder according to the fourth embodiment of the present application.

[0057] In the drawings: 1 - frame; 11 - distal tail; 2 - covering membrane; 201 - fiber bundle; 202 - fiber filament; 21 - outer surface of the covering membrane; 22 - inner surface of the covering membrane; 210 - proximal portion; 220 - distal portion; 3 - connecting structure; 4 - anticoagulant composite coating; 41 - first adhesive layer; 42 - second anticoagulant layer. DETAILED DESCRIPTION

[0058] The advantages and effects of the present application can be easily understood by those skilled in the art from the above description. The present application can also be implemented or applied in other different specific embodiments, and the details in the description can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be noted that the drawings provided in the present embodiment only schematically illustrate the basic concept of the present application, and thus only show the components related to the present application in the drawings, rather than being drawn according to the number, shape and size of the components in actual implementation. The actual implementation of each component can be randomly changed in terms of type, number and ratio, and the layout type of the components can be more complex.

[0059] In addition, each embodiment of the following description has one or more technical features, but this does not mean that all technical features in any embodiment must be implemented simultaneously, or only one or all technical features in different embodiments can be implemented separately. In other words, under the premise of implementation, those skilled in the art can selectively implement part or all of the technical features in any embodiment according to the disclosure of the present application, and according to the design specification or implementation requirements, or selectively implement a combination of part or all of the technical features in multiple embodiments, thereby increasing the flexibility of the implementation of the present application.

[0060] As used in this specification, the singular forms "a," "an" and "the" include plural referents unless the context clearly dictates otherwise. The plural forms "multiple," "plurality" and "a plurality" include two or more referents unless the context clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense of "and / or" unless the content clearly dictates otherwise. The terms "mount," "connected," "connecting," and "connection" are to be broadly interpreted, for example, as including fixed and removable connections, or as permanently, releasably, or detachably connected. It can be a mechanical connection, a direct connection, an indirect connection via an intermediate medium, an internal connection of two elements, or an interaction relationship between two elements. The terms "first," "second," and the like are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between the entities or operations, nor indicate or imply relative importance or implicitly indicate the number of the indicated technical features. It should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," "circumferential," and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as limiting the present application. The specific meanings of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

[0061] In the present application, the term "axial" generally refers to the direction along the central axis of the left atrial appendage closure device, "circumferential" refers to the direction around the central axis of the left atrial appendage closure device, and "radial" generally refers to the diameter direction of the left atrial appendage closure device, i.e. perpendicular to the axial direction; the term "outer side" generally refers to the direction away from the central axis of the left atrial appendage closure device, and the term "inner side" refers to the direction close to the central axis of the left atrial appendage closure device; the terms "distal end" and "proximal end" are described based on the relative orientation and position of each component and element of the left atrial appendage closure device, although non-limiting, "distal end" generally refers to the end of the left atrial appendage closure device that enters the patient's body first during normal use, and "proximal end" is the opposite end of "distal end", i.e. the end of the left atrial appendage closure device closer to the operator. In this document, "not more than" means less than or equal to, and "not less than" means greater than or equal to.

[0062] The core of the present application is to provide a left atrial appendage closure device to solve the common problem of blood clotting on the surface of medical devices in the prior art. The following description is made with reference to the accompanying drawings.

[0063] Figure 1 schematically illustrates a configuration of a left atrial appendage closure device in some embodiments. As shown in Figure 1, the left atrial appendage closure device includes an expandable frame 1, a covering 2 disposed on the frame 1, and a connection structure 3 that can be connected and disconnected from a delivery system.

[0064] The frame 1 is preferably a self-expandable structure. The frame 1 can be made of any suitable material, and currently, a nickel-titanium alloy is the best choice. Alternatively, the frame 1 can be cut from a nickel-titanium tube. The frame 1 has a compressed state and an expanded state, and can be freely converted between the compressed state and the expanded state. Specifically, the left atrial appendage closure device is in the compressed state during delivery via the delivery system, and once the frame 1 is released from the delivery system, the frame 1 autonomously expands to the expanded state (i.e., the use configuration).

[0065] The configuration of the frame 1 is not limited, and common occluders include plug-type occluders and disc-type occluders. For the plug-type occluder described in the figure, the frame 1 is basically a mesh cage structure with a distal end open and a proximal end closed, and the configuration of the entire left atrial appendage closure device is similar to a hemispherical plug. This structure is suitable for the shape of the left atrial appendage opening of most patients. Of course, the configuration of the frame 1 can be adjusted and changed according to the use scenario, and thus is not limited to the structure configuration described in the figure.

[0066] At least part of the outer surface of the frame 1 is covered by the covering 2 to form an occlusion disc surface. The covering 2 can prevent thrombus (i.e., blood clots, etc.) from passing through the covering 2 and entering the bloodstream from the left atrial appendage. In some embodiments, the covering 2 can also promote endothelial cell growth, reduce the risk of restenosis, etc.

[0067] Specifically, the covering 2 is disposed along at least part of the outer surface of the frame 1 to cover at least part of the outer surface of the frame 1. For example, in some cases, the covering 2 can be disposed along part of the outer surface of the frame 1 to expose the distal tail 11 of the frame 1 outside the covering 2 to form a skirt tail. The skirt tail is generally inwardly bent to prevent damage to the tissue structure by the skirt tail of the frame 1 during implantation and after implantation. However, it should be understood by those skilled in the art that the covering 2 can extend along the outer surface of the frame 1 to any extent, for example, to extend along almost the entire outer surface of the frame 1.

[0068] The covering 2 can be a knitted material, a fiber, a fabric, a non-woven fabric, a woven or other suitable structure, and is preferably a fiber mesh woven membrane. The covering 2 can be made of a suitable material, such as polyethylene (PE), polypropylene (PP), polyester, polyurethane (PU), polyethylene terephthalate (PET), or other materials, and the covering 2 can include one material or a combination of multiple materials.

[0069] The height of the covering film 2 can be no more than 2 / 3 of the total height of the frame 1, but is not limited thereto. The total height of the frame 1 refers to the distance from the proximal end to the distal end of the frame 1. The height of the covering film 2 refers to the distance covered by the covering film 2 extending from the proximal end to the distal end of the frame 1.

[0070] The connecting structure 3 is provided at the proximal end of the frame 1 and can be releasably connected to the distal end of the delivery system using a suitable structure. For example, the connecting structure 3 is internally threaded and is threadedly connected to the distal end of the delivery system. However, the threaded connection is not limiting, and in practice, the connecting structure 3 can be releasably connected to the distal end of the delivery system by various means.

[0071] It should also be understood that although the covering film 2 itself has good mechanical properties, biostability and safety, the anticoagulant effect of the covering film material is generally poor, and therefore a material with better hydrophobicity needs to be selected for anticoagulant treatment. The covering film 2 therefore needs to be provided with an anticoagulant coating.

[0072] As shown in FIGS. 1-3, in various embodiments of the present application, the left atrial appendage closure device further comprises an anticoagulant composite coating 4 provided on at least a portion of the outer surface 21 of the covering film 2. The anticoagulant composite coating 4 has an anticoagulant effect, which can reduce the risk of thrombosis on the surface of the device and accelerate the process of endothelialization. Preferably, the covering film 2 is provided with the anticoagulant composite coating 4 only on its outer surface 21, and the other surfaces are non-anticoagulant regions 5 except for the surface provided with the anticoagulant composite coating 4. Specifically, the connecting structure 3 usually does not need to be provided with the covering film 2, and therefore the anticoagulant composite coating 4 does not need to be provided at the connecting structure 3, and if provided, the anticoagulant composite coating 4 is prone to fall off. The frame 1 is mainly responsible for providing a supporting function, and if the anticoagulant composite coating 4 is provided on the frame 1, the anticoagulant composite coating 4 is prone to fall off during the process of releasing the device under compression, and therefore the frame 1 does not need to be provided with the anticoagulant composite coating 4. Therefore, the anticoagulant and non-anticoagulant described in the present application are for the covering film 2.

[0073] In more detail, as shown in FIGS. 2 and 3, the anticoagulant composite coating 4 has a double-layer structure, which includes a first adhesive layer 41 and a second anticoagulant layer 42 provided from inside to outside along the thickness direction of the covering film 2. The first adhesive layer 41 comprises an amphiphilic polymer. The amphiphilic polymer refers to a polymer with both hydrophilic and hydrophobic properties, specifically a high molecular polymer containing both hydrophilic groups and hydrophobic groups. In addition to comprising an amphiphilic polymer, the first adhesive layer 41 can further comprise other components or no further components. Preferably, the first adhesive layer 41 is composed of only an amphiphilic polymer, for example, comprising one amphiphilic polymer or a combination of multiple amphiphilic polymers.

[0074] In this way, the coating 2 can form an anti-coagulation outer surface by the outermost second anti-coagulation layer 42, which can effectively inhibit the formation of thrombus, thereby accelerating the process of endothelialization, thus accelerating the occlusion process and reducing self-reaction. In addition, the second anti-coagulation layer 42 has hydrophobic properties, which can effectively prevent tissue adhesion during implantation, improve the operability of the device, reduce tissue damage caused by device operation, and increase the safety of the operation.

[0075] Specifically, when the anti-coagulation outer surface of the coating 2 is in contact with blood, the second anti-coagulation layer 42 in the anti-coagulation composite coating 4 directly prevents the adhesion and coagulation of blood on the surface of the device. In particular, when the second anti-coagulation layer 42 is an inert hydrophobic polymer coating, the anti-coagulation effect is better. The inert hydrophobic polymer coating can prevent the adhesion of blood plasma components by hydrophobic interaction, thereby achieving anti-coagulation effect.

[0076] Meanwhile, the first adhesive layer 41 (i.e., the coating interlayer) exists between the second anti-coagulation layer 42 and the outer surface 21 of the coating 2. The first adhesive layer 41 is substantially completely covered by the second anti-coagulation layer 42. Since the first adhesive layer 41 has both hydrophilic and hydrophobic properties, the first adhesive layer 41 can better combine with the coating 2 and the second anti-coagulation layer 42, thereby increasing the firmness of the entire coating, reducing the risk of coating falling off, especially not easily falling off when repeatedly pushed in the sheath, thereby enabling the coating to maintain long-term anti-coagulation effect.

[0077] The anti-coagulation composite coating 4 can be provided on the outer surface 21 of the coating 2 by a suitable method, such as physical coating, for example, optionally, ultrasonic spraying, dipping, physical / chemical deposition, plasma coating, atomization spraying, etc. More suitable method is ultrasonic spraying. Here, since the anti-coagulation composite coating 4 is combined with the outer surface 21 of the coating 2 by physical coating, the process is simple and safe.

[0078] In addition, compared with other methods, ultrasonic spraying has more stable process and more controllable preparation process. Moreover, ultrasonic spraying is suitable for single-sided anti-coagulation treatment, and it is easy to adjust and control process parameters, making the process more stable and reliable. The advantage of ultrasonic spraying is also less material and low cost. The ultrasonic spraying can be performed before or after the coating 2 is provided on the frame 1, and preferably, the ultrasonic spraying is performed after the coating 2 is provided on the frame 1, so that the spraying process is more controllable and the spraying effect is better.

[0079] In practice, the anticoagulant composite coating 4 is only required to be provided on the portion of the outer surface 21 of the covering film 2 that is directly in contact with blood, while the inner surface 22 of the covering film 2 does not need to be treated with the anticoagulant coating since the inner portion of most medical devices has little to do with thrombosis and surface endothelialization. Such single-sided anticoagulation not only reduces the amount of material used and the cost, but also helps to fix the entire left atrial appendage closure device. Here, when the inner surface 22 of the covering film 2 is not treated with the anticoagulant, blood clots can be formed in the interior of the filling frame 1 in a short time after the left atrial appendage closure device is implanted in the body, which can help the left atrial appendage closure device to be quickly fixed in the left atrial appendage, so that the entire left atrial appendage closure device is more firmly fixed and less likely to be displaced.

[0080] In the present embodiment, the anticoagulant composite coating 4 does not cover the entire covering film 2, but only covers at least part of the outer surface 21 of the covering film 2 and is uniformly provided along the outer surface 21 of the covering film 2, so that single-sided anticoagulation can be better achieved.

[0081] Referring to FIG. 4, in a preferred embodiment, the covering film 2 is a fiber mesh woven film, wherein the anticoagulant composite coating 4 only covers the surface exposed by the outer fiber filaments 202 in the fiber bundle 201 and the gaps between the outer fiber filaments 202 and the fiber filaments 202. The range of the surface of the outer fiber filaments 202 in the fiber bundle 201 covered by the anticoagulant coating 4 is emphasized by the dashed line in FIG. 4. Here, it is considered that the fiber filaments 202 with and without the anticoagulant composite coating 4 are distinguished under the micro-morphology, that is, it is clear that when the fiber mesh woven film is covered on the outer surface of the frame 1, the inner fiber filaments 202 and the fiber filaments 202 without exposed surface are not coated with the anticoagulant composite coating 4.

[0082] When the covering film 2 is a fiber mesh woven film, it includes one or more fiber bundles 201. Each fiber bundle 201 can include a proper number of fiber filaments 202. The fiber filaments 202 are individual filaments. After a proper number of fiber filaments 202 are wound to form a fiber bundle 201, one or more fiber bundles 201 are formed into a fiber mesh structure of the covering film 2, for example, by weaving, knitting, weaving, electrospinning or other means.

[0083] It should be noted that the anticoagulant composite coating 4 does not encapsulate each of the fiber filaments 202 in the fiber bundle 201. In addition, the anticoagulant composite coating 4 is only provided on the outside of the fiber bundle 201 and does not pass through the fiber bundle 201 to reach the internal region of the fiber bundle 201, so that the internal fiber filaments 202 do not have the anticoagulant composite coating 4, thereby achieving single-sided anticoagulation. At the same time, the anticoagulant composite coating 4 does not block the mesh holes formed by the interweaving of the fiber bundles 201 on the covering film 2, and does not affect the performance of the covering film 2 itself, so that the covering film 2 can maintain the original pore structure (i.e. mesh holes).

[0084] Here, when the covering membrane 2 is a fiber mesh woven membrane, the mechanical support is good, and the mesh of the fiber mesh woven membrane can allow blood flow to pass through, but can prevent thrombus from passing through. Thus, the covering membrane 2 itself is a porous structure. Preferably, the pore size of the covering membrane 2 is 50 μm to 300 μm; the pore size is conducive to the passage of blood through the covering membrane 2, but can effectively prevent the passage of thrombus.

[0085] Preferably, the anticoagulant composite coating 4 is applied to the surface of the fiber filament 202 by ultrasonic spraying.

[0086] As described above, the anticoagulant composite coating 4 is at least required to be provided on the part of the outer surface 21 of the covering membrane 2 that directly contacts the blood, and in practice, the anticoagulant composite coating 4 is thus at least required to be provided on the disc surface of the left atrial appendage closure device (i.e., the position of the section line in FIG. 1), and can cover the entire outer surface of the covering membrane 2 at most.

[0087] Please refer to FIG. 1. In the embodiment, the covering membrane 2 has a proximal portion 210 and a distal portion 220 arranged in the axial direction from the proximal end to the distal end of the frame 1; the proximal portion 210 and the distal portion 220 do not overlap, and both of them surround the frame 1, so that the covering membrane 2 surrounds the frame 1 on the peripheral side of the frame 1. The entire outer surface of the proximal portion 210 is covered with the anticoagulant composite coating 4, and the entire outer surface of the distal portion 220 is the non-anticoagulation region 5. The proximal portion 210 needs to extend from the proximal end of the frame 1 and cover the position of the maximum outer diameter (Dmax) of the frame 1. The distal portion 220 extends from the junction with the proximal portion 210 and covers the distal end of the covering membrane 2, that is, the region of the covering membrane 2 other than the proximal portion 210 is the distal portion 220.

[0088] The distal portion 220 is an anchoring region, which needs to be in contact with the wall of the left atrial appendage to ensure the stability of the device after being implanted in the left atrial appendage, so that the device can stably and effectively occlude the left atrial appendage. The proximal portion 210 is basically not used for anchoring support, and is located on the atrial side, positioned at the entrance of the left atrial appendage, in contact with the blood, and does not need to be anchored.

[0089] Preferably, the anticoagulant composite coating 4 extends from the proximal end of the frame 1 and covers the position of the maximum outer diameter (Dmax) of the frame 1, for example, the anticoagulant composite coating 4 extends beyond the maximum outer diameter (Dmax) of the frame 1, so that the anticoagulant composite coating 4 can sufficiently cover the position of the maximum outer diameter of the frame 1, and the distance beyond the maximum outer diameter can be 3 mm, 5 mm or other sizes. The region of the covering membrane 2 other than the region covered with the anticoagulant composite coating 4 is the non-anticoagulation region 5.

[0090] It should also be understood that the left atrial appendage closure device often needs to be retracted into or out of the delivery sheath during delivery or retraction, and the presence of the anticoagulation composite coating 4 also helps to reduce the friction between the covering 2 and the sheath when entering and exiting the sheath, so that the covering 2 at the position of the maximum outer diameter (Dmax) of the frame 1 has a smaller sheath entry force, and when the anticoagulation composite coating 4 adopts a fluoropolymer coating, a lower surface friction coefficient can be obtained, and the sheath entry force is smaller. In addition, after the left atrial appendage closure device is implanted in the body, the friction between the covering 2 and the left atrial appendage wall can be increased through the non-anticoagulation area 5 on the covering 2, thereby enhancing the stability of the left atrial appendage closure device after implantation.

[0091] Therefore, the sheath entry performance and anchoring performance can also be considered through the anticoagulation area and the non-anticoagulation area 5 of the covering 2, and low sheath entry force and high anchoring force can be achieved without sacrificing other aspects of the device performance, and the safety of the closure device can also be increased. In this application, although the position of the maximum outer diameter of the frame 1 is covered by the anticoagulation composite coating 4, because the fixation of the device is mainly ensured by the anchoring of the non-anticoagulation area 5, the anticoagulation composite coating 4 will not affect the stability of the entire device.

[0092] The first adhesive layer 41 can include a suitable amphiphilic polymer, for example, including at least one of polyamide (PA), polycarbonate (PC), polydimethylsiloxane (PDMS), polycaprolactone (PCL), methyl cellulose (MC), ethyl cellulose (EC), polybutylene adipate / terephthalate (PBAT), and more preferably, at least one of polyacrylamide (PAM) and polyethylene glycol (PEG). Preferably, the first adhesive layer 41 is composed of only amphiphilic polymers.

[0093] The thickness of the first adhesive layer 41 is preferably not more than 0.1 μm; this thickness does not increase the thickness of the entire anticoagulation composite coating 4, while ensuring the firmness of the coating and having good film forming performance. Further, the thickness of the first adhesive layer 41 is not less than 0.05 μm.

[0094] Preferably, the second anticoagulation layer 42 includes a fluoropolymer, such as a combination of one fluoropolymer or a plurality of fluoropolymers.

[0095] When the second anti-coagulation layer 42 comprises a fluorine-containing polymer, the surface of the second anti-coagulation layer 42 exhibits high hydrophobicity due to the presence of fluorine groups, and the anti-coagulation effect is better. Meanwhile, the surface hydrophobicity of the second anti-coagulation layer 42 makes it difficult for fibrinogen and platelets to adhere to the surface of the covering 2, and thus the coagulation reaction is not caused, thereby achieving the anti-coagulation effect. In addition, the surface hydrophobicity of the second anti-coagulation layer 42 allows albumin to be firmly adsorbed on the surface of the second anti-coagulation layer 42, and promotes the migration and crawling of endothelial cells, thereby accelerating the endothelialization of the surface of the material, so as to effectively reduce the complications. In addition, the fluorine-containing polymer also has good film-forming performance, and can uniformly coat the outer surface 21 of the covering 2 and rapidly solidify into a film, and is firmly combined with the first adhesive layer 41 and is not easy to fall off, and will not form particles falling off, and has good biological safety and stability. Of course, the fluorine-containing polymer also has good biocompatibility and stable properties, and can stably achieve the anti-coagulation effect for a long time.

[0096] The second anti-coagulation layer 42 comprises, for example, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), fluorinated ethylene propylene copolymer (FEP), polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP) or the like, or other fluorine-containing polymers having similar properties, and can comprise a combination of one or more of these fluorine-containing polymers. Preferably, the second anti-coagulation layer 42 is composed of polyvinylidene fluoride-hexafluoropropylene copolymer, and the effectiveness and safety of such an anti-coagulation coating are relatively better, and it is not easy to fall off, and has good long-term anti-coagulation effect.

[0097] The second anti-coagulation layer 42 can also comprise a non-fluorine-containing polymer, specifically, a high-molecular polymer (non-fluorine-containing polymer) having better hydrophobicity than the covering 2. The second anti-coagulation layer 42 comprises, for example, polystyrene, polyurethane, polyester and combinations thereof.

[0098] The second anti-coagulation layer 42 can be a single polymer coating or a combination coating of at least two polymers.

[0099] The thickness of the second anti-coagulation layer 42 should not be too large or too small. Preferably, the thickness of the second anti-coagulation layer 42 is not more than 1 μm; in this way, the anti-coagulation effect of the second anti-coagulation layer 42 can be ensured, and it is not easy to fall off, and the safety and effectiveness are better, and it also does not affect the sheathing of the instrument.

[0100] Preferably, the surface contact angle of the second anti-coagulation layer 42 is 100°-130°, for example, 100°, 110°, 120° or 130°; the surface contact angle is conducive to efficient anti-coagulation and better promotion of endothelialization.

[0101] Referring to FIGS. 1-4, the anti-coagulation coating 4 is only coated on at least a portion of the outer surface 21 of the covering film 2, and the areas of the covering film 2 other than the areas coated with the anti-coagulation coating 4 are non-anti-coagulation areas 5. It is worth noting that the expandable frame 1 and the connecting structure 3 can be substantially free of the anti-coagulation coating 4, or in other words, the surfaces of the metal parts are not provided with the anti-coagulation coating 4. Specifically, the connecting structure 3 usually does not need to be provided with the covering film 2, and thus the anti-coagulation coating 4 does not need to be provided at the connecting structure 3, otherwise the anti-coagulation coating 4 is prone to falling off. The expandable frame 1 is mainly responsible for providing support, and if a polymer coating is provided on the expandable frame 1, the polymer coating is more prone to falling off during the instrument crimping and releasing process. Therefore, the anti-coagulation and non-anti-coagulation described in the present application are in relation to the covering film 2.

[0102] It should be understood that the non-anti-coagulation coating is composed of a non-anti-coagulation polymer material, which has less hydrophobic groups and poor hydrophobicity of the groups, and thus in general, the hydrophobicity of the non-anti-coagulation coating is inferior to that of the covering film 2, which is beneficial to the rapid coagulation of blood in the inside of the sealing device and filling the inside area of the sealing device. In addition, the non-anti-coagulation coating can also be made of a non-anti-coagulation polymer material with hydrophilic groups.

[0103] The non-anti-coagulation coating can be coated on the inner surface 22 of the covering film 2 or on the outer surface 21 of the covering film 2. When the non-anti-coagulation coating is coated on the outer surface 21 of the covering film 2, the friction coefficient of the non-coagulation area of the outer surface of the covering film 2 can be increased, and thus the friction between the covering film 2 and the wall of the left atrial appendage is increased, thereby enhancing the stability of the device after implantation.

[0104] Optionally, the non-anti-coagulation coating includes at least one of polyacrylamide (PAM), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and polyetherimide (PEI).

[0105] Optionally, the thickness of the non-anti-coagulation coating is less than or equal to 0.1 μm. Optionally, the surface contact angle of the non-anti-coagulation coating is 45°-90°, such as 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, or 90°, etc.

[0106] The left atrial appendage sealing device provided by the present application is further described below through the following specific examples, and of course, the following specific examples are only used for illustration and do not limit the present application in any way.

[0107]

Example One

[0108] Referring to FIG. 5, the left atrial appendage sealing device provided by Example One of the present application includes a frame 1 formed by cutting a nickel-titanium tube, and a portion of the outer surface of the frame 1 is covered with a PET knitted covering film 2.

[0109] The proximal portion 210 of the PET knitted covering 2 is a blocking disc, and the entire outer surface of the proximal portion 210 is coated with a first adhesive layer 41 composed of polydimethylsiloxane by ultrasonic spraying, and then a second anti-coagulation layer 42 composed of polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP) is coated by ultrasonic spraying.

[0110] It should be understood that the PET knitted covering 2 is a non-anti-coagulation area 5 except for the surface provided with the anti-coagulation composite coating 4, and the non-anti-coagulation area 5 here is directly the PET knitted film material.

[0111] In a separate contact angle test, the contact angles of the anti-coagulation area and the non-anti-coagulation area of the PET knitted film with respect to pure water are tested, and the test results are shown in Table 1 below.

[0112] Table 1: Contact angles (°) of anti-coagulation area and non-anti-coagulation blood

[0113] In Table 1, the contact angle of the double-layer composite anti-coagulation coating area composed of polydimethylsiloxane and polyvinylidene fluoride-hexafluoropropylene copolymer is greater than 90°, so the hydrophobicity of the double-layer composite anti-coagulation coating area is good, and the contact angle of the PET film without coating is less than 90°, which indicates that the hydrophobicity is worse than that of the double-layer composite anti-coagulation coating area.

[0114] In another separate anti-coagulation test, the coagulation performance of the anti-coagulation area and the non-anti-coagulation area of the PET knitted film is characterized by using adult pig artery blood (without heparin) for whole blood immersion, and the results are shown in Table 2 below.

[0115] Table 2: Coagulation time (min) of anti-coagulation area and non-anti-coagulation blood

[0116] In Table 2, the double-layer composite anti-coagulation coating area composed of polydimethylsiloxane and polyvinylidene fluoride-hexafluoropropylene copolymer shows a significant difference in coagulation time from the PET film without coating, which confirms that the double-layer composite anti-coagulation coating area can effectively play a single-sided anti-coagulation effect.

[0117]

Example Two

[0118] Referring to FIG. 6, the application provides a left atrial appendage closure device, wherein the frame 1 is formed by cutting a nickel-titanium tube, and a part of the outer surface of the frame 1 is covered with a PET knitted covering 2.

[0119] The proximal portion 210 of the PET knitted film 2 is a blocking disc, and the entire outer surface of the proximal portion 210 is coated with a first adhesive layer 41 composed of polycaprolactone (PCL) by ultrasonic spraying, and then a second anti-coagulation layer 42 composed of fluorinated ethylene propylene copolymer (FEP) is coated by ultrasonic spraying.

[0120] In a separate contact angle test, the contact angles of the anti-coagulation and non-anti-coagulation regions of the PET knitted film with respect to pure water were tested, and the test results are shown in Table 3.

[0121] Table 3: Contact angles (°) of anti-coagulation and non-anti-coagulation blood

[0122] In Table 3, the contact angle of the double-layer composite anti-coagulation coating region composed of polycaprolactone and fluorinated ethylene propylene copolymer is greater than 90°, so the hydrophobicity of the double-layer composite anti-coagulation coating region is also good, while the contact angle of the uncoated PET film is less than 90°, so the hydrophobicity of the uncoated PET film is poorer than that of the double-layer composite anti-coagulation coating region.

[0123] In another separate anti-coagulation test, the coagulation performance of the anti-coagulation and non-anti-coagulation regions of the PET knitted film was characterized by full blood immersion using adult pig artery blood (without heparin), and the results are shown in Table 4.

[0124] Table 4: Coagulation time (min) of anti-coagulation and non-anti-coagulation blood

[0125] In Table 4, the double-layer composite anti-coagulation coating region composed of polycaprolactone and fluorinated ethylene propylene copolymer also shows a significant difference in coagulation time from the uncoated PET film, confirming that the double-layer composite anti-coagulation coating region can effectively achieve one-sided anti-coagulation effect.

[0126] [Example Three]

[0127] Referring to FIG. 7, the application provides a left atrial appendage closure device, wherein the frame 1 is formed by cutting a nickel-titanium tube, and a portion of the outer surface of the frame 1 is covered with a PET knitted film 2.

[0128] The proximal portion 210 of the PET knitted film 2 is a blocking disc, and the entire outer surface of the proximal portion 210 is coated with a first adhesive layer 41 composed of polycaprolactone (PCL) by ultrasonic spraying, and then a second anti-coagulation layer 42 composed of fluorinated ethylene propylene copolymer (FEP) is coated by ultrasonic spraying.

[0129] In a separate contact angle test, the contact angles of the anti-coagulation region and non-anti-coagulation region of the PET knitted film against pure water were tested, and the test results are shown in Table 5 below.

[0130] Table 5: Contact angles of anti-coagulation region and non-anti-coagulation blood (°)

[0131] In Table 5, the contact angle of the double-layer composite anti-coagulation coating region composed of polycaprolactone and fluorinated ethylene propylene copolymer is also greater than 90°, thus the hydrophobicity of the double-layer composite anti-coagulation coating region is good, and the contact angle of the PET film without coating is less than 90°, and the hydrophobicity of the PET film without coating is worse than that of the double-layer composite anti-coagulation coating region.

[0132] In another separate anti-coagulation test, the coagulation performance of the anti-coagulation region and non-anti-coagulation region of the PET knitted film was characterized by using adult pig artery blood (without heparin) for whole blood immersion, and the results are shown in Table 6 below.

[0133] Table 6: Coagulation time of anti-coagulation region and non-anti-coagulation blood (min)

[0134] In Table 6, the double-layer composite anti-coagulation coating region composed of polycaprolactone and fluorinated ethylene propylene copolymer shows a significant difference in coagulation time compared with the PET film without coating, which confirms that the fluorinated ethylene propylene copolymer (FEP) can effectively achieve the anti-coagulation effect on one side.

[0135] [Example Four]

[0136] Referring to FIG. 8, in Example Four, an expandable frame 1 formed by cutting a nickel-titanium tube is provided, and a portion of the outer surface of the expandable frame 1 is covered with a PET knitted covering film 2.

[0137] The proximal portion 210 of the covering film 2 is the occlusion disc surface, and thus the outer surface of the proximal portion 210 is covered with a FEP hydrophobic coating 43, for example, by ultrasonic spraying, to form an anti-coagulation region.

[0138] Different from Examples One and Two, the inner surface 22 of the covering film 2 in this example is covered with a PAM (polyacrylamide) amphiphilic coating 51, and the portion of the outer surface 21 of the PET knitted film without the FEP hydrophobic coating 43 is directly the PET knitted covering film material, which all form non-anti-coagulation regions 5.

[0139] In a separate contact angle test, the contact angles of the anti-coagulation region and non-anti-coagulation region of the PET knitted film against pure water were tested, and the test results are shown in Table 7 below.

[0140] Table 7: Contact angles of anti-coagulation region and non-anti-coagulation blood (°)

[0141] As can be seen from Table 7, the contact angle of the FEP anti-coagulation region is also greater than 90°, which indicates that the hydrophobicity of the FEP hydrophobic coating 43 is also good, and the contact angle of the PAM non-anti-coagulation region is smaller than that of the non-anti-coagulation region of Example One and Example Two, which indicates that the hydrophobicity of the PAM non-anti-coagulation region is worse.

[0142] In another separate anti-coagulation test, the coagulation performance of the anti-coagulation region and the non-anti-coagulation region of the PET knitted film was characterized by using adult pig artery blood (without heparin) for whole blood immersion, and the results are as follows in Table 8.

[0143] Table 8: Coagulation time (min) of anti-coagulation region and non-anti-coagulation blood

[0144] As can be seen from Table 8, the FEP anti-coagulation region and the PAM non-anti-coagulation region show obvious coagulation time difference, which confirms that the FEP anti-coagulation coating can effectively achieve the anti-coagulation effect of a single side, and the anti-coagulation effect is equivalent to the anti-coagulation effect of the double side of the film.

[0145] [Comparative Example]

[0146] The comparative example is a left atrial appendage closure device, wherein the frame 1 is formed by cutting a nickel-titanium tube, and part of the outer surface of the frame 1 is covered with a PET knitted film 2.

[0147] The proximal portion 210 of the PET knitted film 2 is a blocking disc, at this time, the entire outer surface of the proximal portion 210 is only coated with a second anti-coagulation layer 42 by ultrasonic spraying, and the composition of the second anti-coagulation layer 42 is polyvinylidene fluoride-hexafluoropropylene copolymer (PVDF-HFP).

[0148] In a separate contact angle test, the contact angle of the anti-coagulation region and the non-anti-coagulation region of the PET knitted film with respect to pure water was tested, and the test results are as follows in Table 9.

[0149] Table 9: Contact angle (°) of anti-coagulation region and non-anti-coagulation blood

[0150] In Table 9, the contact angle of the single-layer anti-coagulation coating region formed by polyvinylidene fluoride-hexafluoropropylene copolymer is greater than 90°, so the hydrophobicity of this double-layer composite anti-coagulation coating region is good, and the contact angle of the uncoated PET film is less than 90°, which indicates that the hydrophobicity is worse than that of the double-layer composite anti-coagulation coating region.

[0151] In another separate anti-coagulation test, the coagulation performance of the anti-coagulation region and non-anti-coagulation region of the PET knitted film was characterized by using adult pig artery blood (without heparin) to soak the whole blood, and the results are shown in Table 10.

[0152] Table 10: Coagulation time (min) of anti-coagulation region and non-anti-coagulation blood

[0153] In Table 10, the single-layer anti-coagulation coating region formed by polyvinylidene fluoride-hexafluoropropylene copolymer showed a significant difference in coagulation time compared with the uncoated PET film, which confirmed that the double-layer composite anti-coagulation coating region can effectively play a single-sided anti-coagulation effect.

[0154] In another group of separate coating firmness tests, the left atrial appendage closure devices prepared in different embodiments and comparative examples were loaded into a delivery sheath tube, subjected to a fixed number of in-vitro multiple sheathing tests, and the surface coating morphology was observed by scanning electron microscopy to evaluate the firmness of the coating prepared in different schemes

[0155] Table 11: In-vitro sheathing test results of different embodiments

[0156] As can be seen from Table 11, compared with Examples 1-3, the contact angle and coagulation time performance of the comparative example did not show obvious differences, but the coating firmness results showed that the coating prepared in the comparative example was more prone to fall off, especially as the number of sheathing increased, the coating of the comparative example showed obvious damage and falling off, which confirmed that the double-layer composite anti-coagulation coating has better firmness performance.

[0157] In summary, the present application physically coats the anti-coagulation composite coating 4 on the outer surface 21 of the covering film 2, which on the one hand enhances the anti-coagulation performance of the outer surface of the covering film 2, thereby reducing the possibility of thrombosis on the surface of the device, on the other hand, the hydrophobic surface is conducive to cell adhesion and migration, thereby accelerating the endothelialization process of the surface of the device, and on the other hand, the first adhesive layer 41 can be better combined with the covering film 2 and the second anti-coagulation layer 42, thereby increasing the firmness of the entire coating, reducing the risk of coating falling off, maintaining long-term anti-coagulation effect, and in addition, since the anti-coagulation composite coating 4 is combined with the surface of the covering film 2 in a physical coating manner, it also has the characteristics of simple process and good safety.

[0158] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, but as long as the combinations of the technical features do not exist contradictions, they should be considered as the scope of the present disclosure.

[0159] The above embodiments only express several implementation ways of the present application, and the description is more specific and detailed, but it should not be understood as a limitation to the patent scope of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the protection scope of the present application.

Claims

1. A left atrial appendage closure device, characterized by The frame; a film disposed along at least a portion of an outer surface of the frame; and an anticoagulant composite coating disposed on at least a portion of an outer surface of the film; the anticoagulant composite coating comprising a first adhesive layer and a second anticoagulant layer disposed in a thickness direction of the film from inside to outside, the first adhesive layer comprising an amphiphilic polymer. The film comprises a fiber bundle comprising at least one fiber filament, and the anticoagulant composite coating is disposed on the surface exposed by the outer fiber filament in the fiber bundle and the gap between the outer fiber filament and the fiber filament.

2. The LAA closure device of claim 1, wherein The material of the film is at least one of polyethylene, polypropylene, polyester, polyurethane, polyethylene terephthalate.

3. The LAA closure device of claim 2, wherein The pore size of the film is 50 μm to 300 μm.

4. The LAA closure device of claim 2, wherein, The first adhesive layer comprises at least one of polyamide, polycarbonate, polydimethylsiloxane, polycaprolactone, methyl cellulose, ethyl cellulose, polybutylene adipate / terephthalate.

5. The LAA closure device of claim 1, wherein, The thickness of the first adhesive layer is not more than 0.1 μm.

6. The LAA closure device of claim 1, wherein, The second anticoagulant layer has at least one of the following characteristics:

7. The LAA closure device of claim 1, wherein The thickness of the second anticoagulant layer is not more than 1 μm; The surface contact angle of the second anticoagulant layer is 100° to 130° The second anticoagulant layer comprises a fluorine-containing polymer. The second anticoagulant layer comprises at least one of polytetrafluoroethylene, polyvinylidene fluoride, fluorinated ethylene propylene copolymer, polyvinylidene fluoride-hexafluoropropylene copolymer.

8. The LAA closure device of claim 1, wherein, Further comprising a connection structure disposed at the proximal end of the frame and used for releasable connection with a delivery system; the surface of the connection structure and the surface of the frame are not provided with the anticoagulant composite coating; 9. The LAA closure device of claim 1, wherein, And / or The film has a proximal portion and a distal portion disposed in an axial direction from the proximal end to the distal end of the frame, the proximal portion extends from the proximal end of the frame and covers to the maximum outer diameter of the frame, the anticoagulant composite coating is disposed on the entire outer surface of the proximal portion and extends beyond the maximum outer diameter of the frame. The film is configured to dispose the anticoagulant composite coating only on at least a portion of its outer surface, and the film is further configured to be a non-anticoagulant region on other surfaces except the surface provided with the anticoagulant composite coating.

10. The LAA closure device of claim 1, wherein, The frame; a film disposed along at least a portion of an outer surface of the frame; and an anticoagulant composite coating disposed on at least a portion of an outer surface of the film; the anticoagulant composite coating comprising a first adhesive layer and a second anticoagulant layer disposed in a thickness direction of the film from inside to outside, the first adhesive layer comprising an amphiphilic polymer.

11. A left atrial appendage occluder, characterized by, The film comprises a fiber bundle comprising at least one fiber filament, and the anticoagulant composite coating is disposed on the surface exposed by the outer fiber filament in the fiber bundle and the gap between the outer fiber filament and the fiber filament. The material of the film is at least one of polyethylene, polypropylene, polyester, polyurethane, polyethylene terephthalate. The pore size of the film is 50 μm to 300 μm. ​ ​ ​ 12. The left atrial appendage occluder of claim 11, wherein, ​ 13. The LAA occluder according to claim 11, characterized in that ​ 14. The LAA occluder according to claim 12, characterized in that ​ 15. The LAA occluder of claim 11, wherein, The non-anticoagulation coating is inferior to the covering film in hydrophobicity.

16. The LAA occluder according to claim 15, characterized in that The non-anticoagulation coating has at least one of the following characteristics: The non-anticoagulation coating comprises at least one of polyacrylamide, polyvinyl alcohol, polyvinylpyrrolidone, polyetherimide, polyester, and polyurethane. The non-anticoagulation coating has a thickness less than or equal to 0.1 μm. The non-anticoagulation coating has a surface contact angle of 45° to 90°.

17. The LAA occluder of claim 11, wherein, The anticoagulation coating has at least one of the following characteristics: The anticoagulation coating is superior to the covering film in hydrophobicity. The anticoagulation coating has a thickness less than or equal to 1 μm. The anticoagulation coating has a surface contact angle of 100° to 130°. The anticoagulation coating has a friction coefficient less than that of the non-anticoagulation area on the covering film. The anticoagulation coating comprises a fluorine-containing polymer.

18. The left atrial appendage occluder of claim 17, wherein, The anticoagulation coating comprises at least one of polytetrafluoroethylene, polyvinylidene fluoride, fluorinated ethylene propylene copolymer, and polyvinylidene fluoride-hexafluoropropylene copolymer.

19. The LAA occluder according to claim 17, characterized in that The anti-coagulant coating has a fluorine content of 8 to 80 μg / cm 2 and / or the fluoropolymer has a coefficient of friction of no more than 0.

1.

20. The LAA occluder of claim 11, wherein, The surface of the connecting structure and the surface of the expandable frame are not provided with the anticoagulation coating, and / or the covering film has a proximal portion and a distal portion arranged axially from the proximal end to the distal end of the expandable frame, the proximal portion extends from the proximal end of the expandable frame and covers the position of the maximum outer diameter of the expandable frame, the anticoagulation coating covers the entire outer surface of the proximal portion and extends beyond the maximum outer diameter of the expandable frame.

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