Left atrial appendage occluder with improved connection method

Abstract

The present invention discloses a left atrial appendage occluder with an improved connection method, comprising a sealing portion and an anchoring portion, each of which has a connection portion formed by converging shapes, the connection portions of the sealing portion and the anchoring portion extending toward each other and being fixed in an offset manner. By improving the connection method, the present invention achieves a staggered connection between the sealing portion and the anchoring portion, allowing the sealing portion to adhere more closely to the left atrial appendage and occlude the left atrial appendage opening, thereby reducing the incidence of endoleak and residual shunt.

Description

Technical Field

[0001] The present invention relates to medical devices, and in particular to an interventional treatment device for occluding the left atrial appendage. Background Art

[0002] Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. The incidence of AF increases with age, reaching 10% in people over 75 years old. During AF, the atrial excitation frequency reaches 300-600 beats per minute, the heart rate is often fast and irregular, and the atria lose their effective contractile function. During AF, the contractile force of the left atrial appendage decreases. Coupled with the morphological characteristics of the left atrial appendage itself and the uneven muscle trabeculae within it, the blood flow in the left atrial appendage produces vortices and slows down the flow rate, promoting thrombosis. More than 90% of left atrial thrombi in patients with non-valvular AF are located in the left atrial appendage. After the thrombus breaks off, it will enter the cerebral arteries through the aorta and cause cerebral embolism, that is, stroke.

[0003] Currently, three main clinical approaches are used to prevent and treat the risk of stroke in patients with atrial fibrillation: anticoagulant therapy, surgical intervention, and percutaneous left atrial appendage closure. Anticoagulant therapy involves taking anticoagulants to inhibit blood clotting, thereby reducing the risk of thrombosis in the left atrial appendage (LAA), and thus the incidence of stroke. Clinical trials have shown that anticoagulant therapy can significantly reduce the incidence of stroke, but it is a lengthy process and carries significant complications, primarily bleeding complications, which can be severe. Surgical intervention involves surgical resection or suturing of the LAA. However, this procedure is highly invasive and is typically performed during other procedures such as valve replacement or coronary artery bypass grafting. This procedure is often difficult for patients, especially the elderly, to undergo. Percutaneous LAA closure involves the percutaneous delivery of a LAA closure device to the LAA located in the right atrium of the heart using a small-diameter delivery sheath. A left atrial appendage occluder (LAA) occludes the opening of the left atrial appendage (LAA), preventing blood flow from entering the LAA and thus preventing thrombus formation, thereby preventing thromboembolism in patients with atrial fibrillation. Percutaneous LAA occlusion has been used since 2001, with animal experiments and clinical trials conducted. Clinical trials have shown that LAA occlusion can effectively reduce the incidence of stroke in patients with atrial fibrillation.

[0004] From a structural perspective, there are two main types of left atrial appendage occluders on the market: plug structure and double-disc structure.

[0005] Because left atrial appendage occluders have been used for a relatively short time and the technology is relatively immature, some complications may occur after surgery, affecting the patient's quality of life. Among them, residual shunt from the device is one of the main complications of left atrial appendage occlusion surgery. For the plug structure, 8% of patients had residual shunt complications based on the 6-month follow-up results, and 32% to 34.5% of patients in different centers had some degree of residual shunt complications based on the 12-month follow-up results. For the double-disc structure left atrial appendage occluder, 2% to 16.2% of patients had moderate residual shunt complications based on the 6-month clinical follow-up results from different centers. The high incidence of residual shunt complications will affect the patient's quality of life. Therefore, reducing residual shunt after left atrial appendage occlusion surgery is one of the main goals of improving the clinical application value of left atrial appendage occluders.

[0006] The left atrial appendage occluder with a double-disc structure is usually composed of a sealing part and an anchoring part. After release, the sealing part blocks the left atrial appendage opening position, and the anchoring part is released inside the left atrial appendage and has barbs, which plays the role of fixing the sealing part. After release, the sealing part of the left atrial appendage occluder should be tightly fitted at the left atrial appendage opening position to block the left atrial appendage mouth. If the sealing part cannot be tightly fitted with the left atrial appendage mouth, it may cause the sealing part to hang in the left atrium, which cannot effectively play the effect of blocking the left atrial appendage mouth and may further increase the risk of thrombosis. A major factor that causes the sealing part to be unable to effectively attach to the left atrial appendage mouth position is related to the connection method between the sealing part and the anchoring part, that is: the anchoring part and the sealing part cannot be tightly connected together, the overall length of the product is longer, and the anchoring part is radially compressed after release, further increasing the overall length of the product after release. At the same time, the axial distance between the sealing part and the anchoring part can be increased. After the sealing part is released, it cannot be effectively attached to the left atrial appendage mouth, causing residual shunt. Summary of the Invention

[0007] The present invention provides a left atrial appendage occluder, which improves the connection mode between the sealing part and the anchoring part, can avoid and delay the overall axial lengthening of the left atrial appendage occluder, and further ensure that the sealing part adheres to and occludes the left atrial appendage opening.

[0008] A left atrial appendage occluder with an improved connection method comprises a sealing portion and an anchoring portion, wherein the sealing portion and the anchoring portion respectively have a connection portion formed by shape convergence, and the connection portions of the sealing portion and the anchoring portion extend toward each other and are staggered and fixed.

[0009] In the prior art, the connection parts of the sealing part and the anchoring part are generally aligned with each other. If they are directly connected, the end faces will directly abut each other. Of course, a transition connector can also be used. This structure will cause the overall axial length of the occluder to be too long, which is not conducive to sealing.

[0010] In the present invention, the connection portion between the sealing portion and the anchoring portion is staggered, which can avoid spatial interference during the process of approaching each other, greatly reduce the distance between the sealing portion and the anchoring portion, and improve the sealing effect.

[0011] Optionally, the sealing portion and the anchoring portion are an integral structure with their respective connecting portions, or are separate structures fixed to each other.

[0012] The sealing part and the anchoring part can be processed by weaving or cutting respectively. The sealing part (anchoring part) can adopt a regular or irregular wire frame structure. When adopting a wire frame structure, a skeleton can be set at an appropriate position as needed to improve the strength. The skeleton can be an increase in cross-sectional area relative to other parts, or at least have higher strength. The mesh structure can be a regular or irregular cell, preferably a diamond or approximately diamond-shaped cell, at least it can be compressed in the radial direction for easy recovery and release. The mesh structure has a clear warp and weft structure, and the intersection of the warp and weft can be a fixed node. It is more preferred to adopt a non-fixed method, that is, the warp and weft can be dislocated and slipped to provide compliance and deformation ability.

[0013] The sealing part and the anchoring part can be cut or woven into an integral structure with their respective connecting parts, or the connecting parts can be independent parts assembled and fixed by welding or other means. The preferred method is an integral structure, which is easy to process and ensures overall strength.

[0014] Optionally, the shape convergence is overall convergence or local convergence.

[0015] The sealing part and the anchoring part have a certain diameter range because they are to block the left atrial appendage, while the connecting part has a thinner diameter. The diameter change therebetween can be gradual or sudden. For example, when the overall convergence method is adopted, the position of the diameter change presents a conical structure, and the local convergence can be regarded as a sudden change in diameter, such as a sudden change from a larger cross-sectional area to a thinner rod or bundle.

[0016] Optionally, the connecting portions on both the sealing portion and the anchoring portion are in one place and are connected to each other; or the connecting portions on both the sealing portion and the anchoring portion are in multiple places and are connected to each other in a one-to-one correspondence.

[0017] There is no strict limit on the number and location of the connection parts. When only one connection part is used, it is usually located at the sealing part or

[0018] Optionally, the connection parts of the sealing part and the anchoring part are directly connected or connected through a connecting piece.

[0019] Direct connection means that the connecting parts of the two are in contact with each other and are fixed to each other by welding, clamping, winding, etc., while connection through a connecting piece means that the connecting parts of the two may not be in contact with each other, but are fixed respectively relative to the connecting piece. The connecting piece can be a single component or an assembly composed of multiple components.

[0020] Optionally, the connection portion between the sealing portion and the anchoring portion extends along a straight line; or

[0021] the connection of one extends along a straight line and the extension of the other extends along a curved line; or

[0022] The connection between the two extends along a curve.

[0023] The sealing part and the anchoring part are arranged relative to each other, and their connecting parts extend close to each other and are connected. Their paths are not strictly restricted during the extension process. In order to simplify the structure, it is preferred that the connecting parts of the sealing part and the anchoring part extend along a straight line.

[0024] The shape of the connecting portion itself may be a simple straight rod or a more complex three-dimensional structure, so the straight extension here should be understood as an overall trend, that is, there is no overall detour or bend in the extension process.

[0025] As a further preference, the connection portions of the sealing portion and the anchoring portion both extend along the axial direction of the left atrial appendage occluder.

[0026] Optionally, the connection parts of the sealing part and the anchoring part are nested with each other or deviated from each other at the mutually matching positions.

[0027] Since the connection parts of the sealing part and the anchoring part are arranged in a staggered manner, they can be nested or deviated from each other to achieve continued extension under the premise of staggered arrangement without spatial interference. The mutual deviation here is relative to the nesting and should not be understood as being away from each other. For example, on a cross section perpendicular to the axis of the left atrial appendage occluder, the connection parts of the sealing part and the anchoring part can be close to each other or have a certain gap.

[0028] Optionally, the connection portions of the sealing portion and the anchoring portion extend toward each other and pass over each other's ends.

[0029] When one of the connecting parts passes over the other end, it also means that the end of the other connecting part passes over its own end. In this way, the two connecting parts are arranged side by side or at least partially overlap along the projection perpendicular to the axis of the left atrial appendage occluder at the mutually cooperating position.

[0030] When the connecting parts of the sealing part and the anchoring part are nested with each other, their projections must overlap. When they deviate from each other, the projection shape is related to the viewing angle, so side by side or partial overlap are possible. If the sealing part and the anchoring part are misaligned but do not continue to extend beyond the other end, there is still space to further pull the sealing part and the anchoring part closer, and the product structure is not compact enough.

[0031] Optionally, the sealing portion and the anchoring portion are in contact with each other in peripheral areas of their respective connecting portions.

[0032] The mutual contact can block the gap between the sealing part and the anchoring part, thereby improving the sealing effect.

[0033] As a further preference, the sealing portion and the anchoring portion are pressed against each other in the peripheral areas of their respective connecting portions.

[0034] The sealing part and the anchoring part can be pressed against each other by applying a pre-tightening force. After the occluder is released, it can better adhere to and seal the left atrial appendage orifice. Even if the anchoring part or the sealing part is radially compressed and lengthened, the sealing part and the anchoring part can still be kept in contact to ensure the sealing effect.

[0035] In combination with the existing technology, one or more flow-blocking films are provided in the sealing portion; and the periphery of the anchoring portion may also be coated, for example, the outer surface of the anchoring disc may be fully or partially coated.

[0036] Unless otherwise specified, the shapes and positional relationships described in the present invention are the states of the left atrial appendage occluder after it is released and expanded in the body, which can also be referred to as the released state or the expanded state. Before release, the left atrial appendage occluder is compressed in the delivery device, which can be referred to as the compressed state or the pre-release state.

[0037] Optionally, the sealing portion and the anchoring portion are each independently a wireframe structure or a mesh structure.

[0038] Optionally, the sealing portion is a sealing disk or a sealing plug.

[0039] The "disc" and "plug" here are understood to refer to the general shape characteristics, for example, the disc is flat, and the shape of its outer edge basically conforms to the physiological structure characteristics of the left atrial appendage, such as round or other shapes according to actual needs.

[0040] For example, the plug is cylindrical with a certain thickness, such as an approximate cylinder, a truncated cone, etc., but the shape of its periphery or busbar is not strictly limited. On the one hand, it can refer to the existing technology, and on the other hand, it can be based on actual needs. The shape of the sealing part itself is not the focus of improvement of the present invention. Of course, the present invention provides a preferred or improved solution.

[0041] Preferably, the sealing portion is a sealing disk having a predetermined forming state in which it is not in contact with the anchoring portion and a pressed state in which it is in contact with the anchoring portion; relative to the predetermined forming state, the middle portion of the sealing disk in the pressed state has a deformation that is axially protruding toward the anchoring portion.

[0042] Preferably, the sealing portion includes a disk surface facing away from the anchoring portion, a disk bottom facing the anchoring portion, and a waist connecting the disk surface and the disk bottom, wherein the disk bottom is flat or the middle of the disk bottom is convex toward one side of the anchoring portion.

[0043] The disk surface, disk bottom and waist constitute a cage structure as a whole. One or more flow-blocking membranes can be arranged inside the cage structure. The cage structure can be closed or partially open except for the necessary hollow parts. When weaving the sealing part, there can be a convergent end at the disk bottom and the disk surface.

[0044] Since the cage-shaped structure has a certain space inside, it can ensure the sealing effect even if there is a certain deformation, which is particularly suitable for the feature of being tightly pressed against the anchoring part in the present invention.

[0045] The diameter of the cage structure is mainly the diameter of the waist which is basically equivalent to the diameter of the anchoring part, while the diameter of the disk surface is slightly larger than the diameter of the waist to improve the sealing effect of the end.

[0046] Optionally, the sealing portion has a predetermined forming state in which it is not in contact with the anchoring portion and a pressed state in which it is in contact with the anchoring portion. In the predetermined forming state, the diameter of the disk surface is larger than the diameter of the disk bottom.

[0047] The diameter of the disk surface or the disk bottom described here can be approximately circular. If it is other shapes, it can be understood as the relative relationship between the cross-sectional area or the overall thickness. Taking the circle as an example, since the diameter of the disk surface is larger than the diameter of the disk bottom, the overall shape is a truncated cone, with a slightly larger top surface at the top, which converges more downwards, and a slightly smaller bottom surface at the bottom, so that when it is in contact with the anchoring part, it can fit in with the anchoring part in a conforming manner.

[0048] Optionally, the sealing portion has a predetermined forming state in which it is not in contact with the anchoring portion and a pressed state in which it is in contact with the anchoring portion. Relative to the predetermined forming state, the sealing portion in the pressed state has deformation at the waist and / or the bottom of the disc.

[0049] The pre-formed state refers to the shape obtained by heat setting after the sealing part itself is processed and is not assembled or subjected to external force. After assembly, it is pressed against the anchor part, and in order to increase or maintain this pre-tightening force, it is deformed after being pressed against the anchor part.

[0050] Optionally, relative to the predetermined forming state, the sealing portion in the pressed state has a radially contracted deformation at the waist.

[0051] When the sealing portion and the anchoring portion move away from each other or are radially compressed, the radial contraction can offset or slow down the axial extension to ensure the sealing of the left atrial appendage opening. The radial contraction can also create a certain taper at the waist, which can better fit the left atrial appendage and improve the sealing effect.

[0052] Optionally, relative to the predetermined forming state, the sealing portion in the pressed state has a deformation at the bottom of the disc that is axially convex toward the anchoring portion.

[0053] Based on a similar principle, the deformation of the axial projection toward the anchoring portion can also offset or delay the overall axial extension of the left atrial appendage occluder, thereby maintaining the sealing portion and the anchoring portion in contact as much as possible to ensure a sealing effect.

[0054] Optionally, the sealing portion abuts against the anchor portion at least at the outer edge of the disc bottom. The abutment between the outer edge of the disc bottom and the anchor portion can achieve greater deformation of the sealing portion under the same preload force, which is more conducive to compensating and offsetting axial extension.

[0055] Optionally, the sealing portion and the anchoring portion are staggeredly connected through their respective connecting ends.

[0056] Optionally, the sealing portion and the anchoring portion are each converged and connected via a connector.

[0057] If the structure is a mesh, the threads used to weave the sealing portion or the anchoring portion are individually bundled and connected by a connector. This bundling is a structural feature and also includes the corresponding step during processing, that is, bringing multiple threads together into a bundle.

[0058] If it is a wire frame structure, the sealing part or anchoring part is generally cut by pipe, and the end of the pipe can be understood as the convergence part.

[0059] Optionally, the side of the sealing portion facing the anchoring portion is the bottom, the bottom of the sealing portion has a first convergence, the radial middle portion of the anchoring portion has a second convergence, and the connecting member has two channels to respectively pass through and fix the first convergence and the second convergence.

[0060] The first and second tightening portions are pulled in opposite directions relative to the connector to bring the sealing portion and the anchoring portion body closer to each other until they are in contact with each other. Build-up of independent channels can avoid interference during pulling and facilitate assembly.

[0061] Optionally, the two channels on the connector are arranged side by side or nested inside and outside. Generally speaking, the two channels are staggered with each other to further avoid interference during traction and facilitate assembly.

[0062] Optionally, the anchoring portion extends from the connecting piece back to the sealing portion to form an extension section, and the side of the extension section away from the connecting section is turned outward and folded back to the bottom of the sealing portion to form a folded section, and the folded section is against the bottom of the sealing portion.

[0063] The anchoring part is an outward-turned structure as a whole, and the return section surrounds the periphery of the extension section to form a double-layer structure. There is a certain space inside the double-layer structure, which can absorb and allow the anchoring part to deform after it is pressed against the sealing part, but does not weaken its anchoring effect.

[0064] Optionally, the folded section is folded inwardly at the bottom position of the sealing portion to form a closing section, and the closing section is against the bottom of the sealing portion.

[0065] The closing section extends roughly radially inward, forming surface contact with the bottom of the sealing portion, which is more conducive to applying pre-tightening force. Although the anchoring portion and the sealing portion are both hollow structures, the so-called surface contact here can be understood as the contact between the mesh surfaces, and does not require physical surface contact.

[0066] Optionally, the first convergence is located at the center of the bottom of the sealing portion, and the closing section is against the outer edge of the bottom of the sealing portion, so that the bottom of the sealing portion can be made into an inverted cone by the pulling of the pre-tightening force.

[0067] Optionally, the closing section is suspended on the periphery of the extending section or is connected to the extending section.

[0068] "Suspended" means that there is no connection with the periphery of the extension section or it is only in contact with the periphery. When each other is deformed, they can move freely relative to each other. If there is a connection, it can be a fixed connection or a sliding or rotating fit, which to a certain extent restricts the relative movement of the two.

[0069] Optionally, the extension section is conical, with the large end side (i.e. the cone bottom side) away from the connecting piece and open.

[0070] The extension section is trumpet-shaped for easy recovery, and the expanded portion can also improve the strength and stability of the structure.

[0071] Optionally, the anchor portion has a predetermined forming state in which it is not pressed against the sealing portion and a pressed state in which it is in contact with the sealing portion. In the predetermined forming state, the connector is further away from the sealing portion than the closing section in the axial direction of the anchor portion.

[0072] That is, when the sealing part and the anchoring part are relatively close, the closing section contacts the bottom of the sealing part first. Since there is still a distance between the connecting piece and the sealing part, this distance also leaves space and possibility for further pulling to form pre-tightening force.

[0073] Optionally, in the tightened state, the connecting piece is flush with the closing section in the axial direction of the anchoring portion or is further away from the sealing portion than the closing section.

[0074] Optionally, the connecting member includes an inner ring and an outer ring that are nested with each other, the bottom of the sealing part has a first convergence, and the radial middle part of the anchoring part has a second convergence, and one of the first convergence and the second convergence is inserted into and fixed in the inner ring, and the other is inserted into and fixed in the gap between the inner ring and the outer ring.

[0075] Optionally, the connecting member includes an inner ring and an outer ring that are nested with each other, the bottom of the sealing portion has a first contraction, and the radial middle portion of the anchoring portion has a second contraction, and one of the first contraction and the second contraction is inserted into and fixed in the gap between the inner ring and the outer ring, and the other passes through the inner ring and is fixed with an anti-slip head at the exit end that abuts against the connecting member.

[0076] Optionally, the connecting piece includes a main body having two side-by-side channels, the bottom of the sealing part has a first convergence, and the radial middle part of the anchoring part has a second convergence, the first convergence and the second convergence respectively pass through the corresponding channels, and anti-slip heads are respectively fixed at the outlet ends to abut against the main body.

[0077] The connector and anti-detachment head can be made of stainless steel, nickel-titanium alloy, or other metal materials that meet biocompatibility requirements. The left atrial appendage occluder of the present invention is delivered to the left atrial appendage of the heart via a delivery sheath via percutaneous puncture, thereby occluding the left atrial appendage and preventing the risk of thrombosis in the left atrial appendage and subsequent stroke in patients with atrial fibrillation.

[0078] The present invention realizes the staggered connection of the sealing part and the anchoring part through an improved connection method, which can make the sealing part adhere to the left atrial appendage more closely and block the left atrial appendage opening, thereby reducing the incidence of endoleak and residual shunt. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 is a schematic diagram of the left atrial appendage occluder in Example 1;

[0080] Figure 2 This is a schematic diagram of the sealing portion after heat setting in Example 1;

[0081] Figure 3 This is a schematic diagram of the anchoring portion after heat setting in Example 1;

[0082] Figure 4a Schematic diagram of the connection process between the anchoring portion and the sealing portion (on the anchoring portion side) in Example 1;

[0083] Figure 4b for Figure 4a Enlarged view of part A;

[0084] Figure 5 Schematic diagram of the connection process between the anchoring portion and the sealing portion (sealing portion side) in Example 1;

[0085] Figure 6 This is a schematic diagram of the anchoring portion and the sealing portion beginning to dock in Example 1;

[0086] Figure 7a This is a schematic diagram of the completed connection between the anchoring portion and the sealing portion in Example 1;

[0087] Figure 7b Schematic diagram of the connection between the sealing part and the anchoring part in the prior art;

[0088] Figure 7c for Figure 7a Schematic diagram of partial omission;

[0089] Figure 8 Schematic diagram of the left atrial appendage occluder in Example 1 being placed in the left atrial appendage for occlusion;

[0090] Figure 9a is a schematic diagram of the left atrial appendage occluder in Example 2;

[0091] Figure 9b for Figure 9a Enlarged view of part A;

[0092] Figure 10 Schematic diagram of the connection process between the anchoring portion and the sealing portion in Example 2;

[0093] Figure 11a Schematic diagram of the left atrial appendage occluder in Example 3;

[0094] Figure 11b for Figure 11a Enlarged view of part A;

[0095] Figure 12a Schematic diagram of the connection process between the anchoring portion and the sealing portion in Example 3;

[0096] Figure 12b for Figure 12a Enlarged view of part A;

[0097] Figure 13 Schematic diagram of the connection process between the anchoring portion and the sealing portion in Example 3;

[0098] Figure 14 Schematic diagram of the left atrial appendage occluder in Example 4. DETAILED DESCRIPTION

[0099] Example 1:

[0100] like Figure 1 As shown, the left atrial appendage occluder 1000 according to the first embodiment of the present invention comprises a sealing portion 1100 and an anchoring portion 1200 connected to each other. The sealing portion 1100 and the anchoring portion 1200 are both braided with nickel-titanium wire.

[0101] The sealing part 1100 includes a disk surface 1110, a waist 1120 and a disk bottom 1170. There is a bolt head 1130 at the end of the disk surface, a layer of PET flow-blocking film 1140 is sewn inside the disk surface, a layer of flow-blocking film 1150 is sewn inside the middle of the waist, and a layer of flow-blocking film 1160 is sewn inside the disk bottom.

[0102] The anchoring portion is composed of an inner mesh cone 1210, an outer mesh cylinder 1220, an outer end bent portion 1230, an arc transition portion 1240 between the inner mesh cone 1210 and the outer mesh cylinder 1220, and an arc transition portion 1250 between the outer mesh cylinder 1220 and the end bent portion 1230. There are evenly distributed barbs 1270 on the circumference of the outer surface of the outer mesh cylinder 1220.

[0103] The inner mesh cone 1210 is equivalent to the extension section; the outer mesh cylinder 1220 is equivalent to the return section; and the outer end bending portion 1230 is equivalent to the closing section.

[0104] The distal end of the sealing portion disc bottom is connected to the conical proximal end of the inner layer mesh of the anchoring portion, and the connection can be achieved by fastening with a rigid sleeve or laser welding.

[0105] Before being connected, the sealing part and the anchoring part are respectively formed by using cylindrical braided nickel-titanium mesh and undergoing high-temperature heat treatment in a mold. Figure 2 、 Figure 3 They are respectively the sealing part 1100 and the anchoring part 1200 of the left atrial appendage occluder 1000 after heat treatment and shaping in Example 1 of the present invention, wherein the sealing part 1100 has a distal nickel-titanium wire bundle, and the inner layer mesh cone 1210 of the anchoring part 1200 has a proximal nickel-titanium wire bundle.

[0106] Figures 4a to 7c This is a connection method for the sealing portion 1100 and the anchoring portion 1200 of the left atrial appendage occluder 1000 in the first embodiment of the present invention.

[0107] The proximal nickel-titanium wire 1261 of the anchoring part is gathered between an outer steel sleeve 1262 (equivalent to an outer ring) and an inner steel sleeve 1263 (equivalent to an inner ring). As can be seen in the figure, the nickel-titanium wire used to braid the anchoring part is gathered at the proximal end of the extension section and connected to the inner and outer steel sleeves serving as connectors. Figure 4a It can be seen that the inner and outer steel sleeves serving as connectors are further away from the sealing portion than the closing section. The anchoring portion of the roll-up structure is generally bowl (or nest) shaped, and the connector is located inside the bowl, that is, sunk below the bowl mouth.

[0108] Then, the inner and outer steel sleeves and the proximal nickel-titanium wire 1261 therebetween are fixed together by welding or pressing. The inner steel sleeve 1263 is a hollow structure. Then, the nickel-titanium wire outside the proximal end of the outer steel sleeve 1262 is removed by cutting or laser processing.

[0109] like Figure 5 and Figure 6The distal nickel-titanium wire 1171 of the sealing part is gathered in the middle of the bottom of the disc and then passes through the inner steel sleeve 1263, which can apply a certain pulling force to tightly connect the sealing part 1100 and the anchoring part 1200, forming a certain pre-tightening force. The waist of the sealing part is stretched into a tapered structure through this pre-tightening force, and the overall height of the left atrial appendage occluder can be reduced at the same time.

[0110] like Figure 6 The sealing structure shown in the figure is as follows: the distal nickel-titanium wire 1171 of the sealing part is fixed together through a steel sleeve 1172 (equivalent to an anti-slip head). The steel sleeve 1172 should slide and press against the distal end of the inner steel sleeve 1263 before being fixed to the distal nickel-titanium wire 1171. The outer diameter of the steel sleeve 1172 is larger than the inner diameter of the inner steel sleeve 1263 to prevent the distal nickel-titanium wire 1171 from slipping out of the inner steel sleeve 1263.

[0111] The excess distal nickel-titanium wire 1171 at the distal end of the sealing portion is then cut off or laser-processed. The steel sleeve material of the present invention can be stainless steel, nickel-titanium alloy or other metal materials that meet biocompatibility requirements. In this embodiment, stainless steel is selected.

[0112] After the sealing part 1100 is connected to the anchoring part 1200, a layer of PET flow-blocking film 1140 is sutured inside the sealing part of the left atrial appendage occluder by suturing, and a layer of PET flow-blocking film 1150 and a layer of PET flow-blocking film 1160 are sutured in the middle of the waist of the sealing part and the bottom of the disk respectively. Figure 1 shown.

[0113] The sealing part 1100 is a cage-shaped structure with a certain internal space. In the pre-formed state, the waist is roughly cylindrical. Figure 2 and Figure 7a It can be seen that after assembly, the bottom of the disc and the closing section are pressed against each other, and the distal side of the waist is radially contracted and deformed with a certain taper, forming a roughly inverted frustum structure. Not only that, under the action of the preload force, the middle part of the bottom of the disc also bulges toward the anchoring part.

[0114] See also Figure 7b In the prior art, the sealing portion 1100 has a connecting portion 1180, and the anchoring portion 1200 has a connecting portion 1280. The connecting portions of the sealing portion 1100 and the anchoring portion 1200 extend toward each other and align with each other, and are fixed by welding or annular hoops after extending to contact each other.

[0115] As can be seen from the figure, there is a large gap between the sealing portion 1100 and the anchoring portion 1200, and the sealing effect needs to be improved.

[0116] In this embodiment, the respective convergence parts of the sealing part 1100 and the anchoring part 1200 serve as the connecting part. Figure 5It can be seen that the connecting portion of the sealing portion 1100, that is, the distal nickel-titanium wire 1171 after being converged, is formed by the convergence of the disk bottom 1170, and the disk bottom 1170 with a larger area suddenly converges to form a thinner convergence.

[0117] Combine Figure 4a It can be seen that the connecting portion of the anchoring portion 1200, that is, the proximal nickel-titanium wire 1261 after being converged, gradually converges from the inner layer mesh cone 1210 to form a thinner convergence.

[0118] See also Figure 7c After assembly is completed, the connecting part of the anchoring part 1200 is fixed between the outer steel sleeve 1262 and the inner steel sleeve 1263, and the connecting part of the sealing part 1100 passes through the inner steel sleeve 1263 and is fixed by the steel sleeve 1172. The steel sleeve 1172 is pressed against the distal side of the inner steel sleeve 1263. From this connection method, it can be seen that the connecting part of the sealing part 1100 is in the central area, and the connecting part of the anchoring part 1200 is in its peripheral area. The connecting parts of the two are staggered inside and outside, and pass over each other's end parts.

[0119] Along the axis of the left atrial appendage occluder Figure 7c If projected in the middle A direction, the connecting part of the anchoring part 1200 and the connecting part of the sealing part 1100 are nested with each other, and their respective extension paths are straight lines, that is, they extend along the axial direction of the left atrial appendage occluder. Due to the staggered arrangement, there is no spatial interference when they extend respectively, and the distance between the sealing part 1100 and the anchoring part 1200 is shortened as much as possible until they are pressed against each other in the outer area of ​​the connecting part.

[0120] Along the vertical axis of the left atrial appendage occluder Figure 7c In case of projection in the middle B direction, the connection portion of the anchoring portion 1200 overlaps with the connection portion of the sealing portion 1100 , and the connection portion of the sealing portion 1100 is within the projection area of ​​the connection portion of the anchoring portion 1200 .

[0121] In this embodiment, the sealing portion 1100 and the anchoring portion 1200 are all integral structures with their respective connecting portions. Not only that, they can also be in a split form, that is, there is no convergence extending toward each other, but both are fixed with connecting rods in the middle of the opposite side, one of the connecting rods is a hollow structure, and the other connecting rod passes through it, so that a fixed connection of the inside and outside can be achieved.

[0122] like Figure 8As shown, after the left atrial appendage occluder 1000 of this embodiment is delivered into the left atrial appendage through a percutaneous catheter delivery system, the left atrial appendage occluder is anchored in the left atrial appendage, and the connection method between the anchoring part and the sealing part forms a pre-tightening force between the two parts. The tapered structure of the waist 1120 of the left atrial appendage occluder can better adhere to the opening position of the left atrial appendage, and the pre-tightening force can make the sealing part disk 1110 adhere to the left atrial appendage more closely, so that the three layers of coating can effectively block the blood flow into the left atrial appendage, so as to reduce the incidence of internal leakage.

[0123] Example 2:

[0124] The left atrial appendage occluder 2000 of the second embodiment of the present invention is composed of a sealing part 2100 and an anchoring part 2200. The structural shape of the sealing part and the anchoring part after heat setting is the same as that of the first embodiment. The difference from the first embodiment is that the connection method of the anchoring part and the sealing part is different. Figure 9a and Figure 9b shown.

[0125] The sealing portion 2100 and the anchoring portion 2200 of the left atrial appendage occluder 2000 after heat treatment and shaping in the second embodiment of the present invention, wherein the sealing portion 2100 has a distal nickel-titanium wire bundle, and the anchoring portion 2200 has a proximal nickel-titanium wire bundle.

[0126] like Figure 10 As shown, in this embodiment, the distal nickel-titanium wire 2171 of the sealing portion and the proximal nickel-titanium wire 2261 of the anchoring portion are each bundled and passed through a steel sleeve 2272 (equivalent to the connector body) from opposite directions (towards).

[0127] along Figure 10 Apply tension to the two bundles of nickel-titanium wires in the direction indicated by the middle arrows, so that the sealing disk 2100 and the anchoring portion 2200 are tightly connected, forming a certain pre-tightening force, and through this pre-tightening force, the waist 2120 of the sealing portion is stretched into a tapered structure; then Figure 9b The proximal nickel-titanium wire 2261 of the anchoring part can be fixed together through the steel sleeve 2172 by pressing or welding, and the distal nickel-titanium wire 2171 of the sealing part can be fixed together through the steel sleeve 2263 by pressing or welding, and then clamped on both sides of the steel sleeve 2272, and the excess nickel-titanium wire can be cut off or processed by laser.

[0128] See also Figure 9b In this embodiment, the sealing portion 2100 and the anchoring portion 2200 also adopt a similar method to that of the first embodiment, with an integral structure and connecting portions extending toward each other. The difference is that the connecting portions of the two are staggered in a mutually deviated manner. Taking the orientation in the figure as an example, one is on the left and the other is on the right.

[0129] Likewise, spatial interference when extending toward each other can be avoided, and the sealing portion 2100 and the anchoring portion 2200 can be brought as close to each other as possible.

[0130] Example 3:

[0131] The left atrial appendage occluder 3000 in the third embodiment of the present invention is composed of a sealing portion 3100 and an anchoring portion 3200. The structural shape of the sealing portion 3100 and the anchoring portion 3200 after heat setting is the same as that of the first and second embodiments. The difference from the first and second embodiments is that the connection method between the anchoring portion and the sealing portion is different. Figure 11a and Figure 11b shown.

[0132] The sealing portion 3100 and the anchoring portion 3200 of the left atrial appendage occluder 3000 after heat treatment and shaping in the third embodiment of the present invention, wherein the sealing portion 3100 has a distal nickel-titanium wire bundle, and the anchoring portion 3200 has a proximal nickel-titanium wire bundle. Figures 12a to 13 This is another connection method between the sealing portion 3100 and the anchoring portion 3200 of the left atrial appendage occluder 3000 in the third embodiment of the present invention.

[0133] In the left atrial appendage occluder 3000 of this embodiment, the distal nickel-titanium wire 3171 of the sealing portion 3100 is bundled and passed between the outer steel sleeve 3172 and the inner steel sleeve 3173, and then the nickel-titanium wires of the outer steel sleeve 3172 and the inner steel sleeve 3173 are fixed together by welding or pressing. The inner steel sleeve 3173 is a hollow structure, and then the nickel-titanium wire outside the distal end is removed by cutting or laser processing.

[0134] The proximal nickel-titanium wire 3261 of the anchoring part is bundled and passes through the inner steel sleeve 3173 at the distal end of the sealing part, and penetrates into the middle of the mesh of the sealing part. A certain pulling force can be applied to tightly connect the sealing part and the anchoring part to form a certain pre-tightening force, and through this pre-tightening force, the waist of the sealing part is stretched into a tapered structure; then the proximal nickel-titanium wire bundle of the anchoring part is fixed together through the steel sleeve 3162, the outer diameter of this steel sleeve 3162 is larger than the inner diameter of the inner steel sleeve 3173 of the sealing part, and the excess nickel-titanium wire at the proximal end of the anchoring part is cut off or laser-treated.

[0135] Example 4:

[0136] The difference between this embodiment and the first embodiment lies in the shape of the sealing portion 4100, such as Figure 14 shown.

[0137] In this embodiment, the sealing portion 4100 is in the shape of a flat disk, namely a sealing disk. Under the action of the pre-tightening force, the middle portion of the sealing disk bulges toward one side of the anchoring portion.

[0138] The above disclosure is merely a specific embodiment of the present invention, but the present invention is not limited thereto. Those skilled in the art may make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Such modifications and variations are clearly within the scope of protection claimed by the present invention. Furthermore, although certain specific terms are used in this specification, these terms are for convenience only and do not constitute any particular limitation on the present invention.

Claims

1. A left atrial appendage occluder with an improved connection method, comprising a sealing portion and an anchoring portion, characterized in that: The sealing portion and the anchoring portion each have a connecting portion formed by converging shapes, and the connecting portions of the sealing portion and the anchoring portion extend toward each other and are staggered and fixed; The sealing portion and the anchoring portion are pressed against each other at the peripheral areas of their respective connecting portions; The sealing portion has a predetermined state in which it is not in contact with the anchor portion and a pressed state in which it is in contact with the anchor portion; The sealing portion in the pressed state is deformed relative to the predetermined state; One or more flow-blocking films are arranged in the sealing portion.

2. The left atrial appendage occluder with improved connection method according to claim 1, characterized in that: The sealing portion and the anchoring portion are integrally formed with their respective connecting portions, or are separate structures fixed to each other.

3. The left atrial appendage occluder with improved connection method according to claim 1, characterized in that: The shape convergence is overall convergence or local convergence.

4. The left atrial appendage occluder with improved connection method according to claim 1, characterized in that: The connecting portions on both the sealing portion and the anchoring portion are located at one location and are connected to each other; or the connecting portions on both the sealing portion and the anchoring portion are located at multiple locations and are connected to each other in a one-to-one correspondence.

5. The left atrial appendage occluder with improved connection method according to any one of claims 1 to 4, characterized in that: The connection parts of the sealing part and the anchoring part are directly connected or connected through a connecting piece.

6. The left atrial appendage occluder with improved connection method according to claim 1, characterized in that: The connection between the sealing portion and the anchoring portion extends in a straight line; or the connection of one extends along a straight line and the extension of the other extends along a curved line; or The connection between the two extends along a curve.

7. The left atrial appendage occluder with improved connection method according to claim 1, characterized in that: The connection parts of the sealing part and the anchoring part are nested with each other or deviated from each other at the mutually matched positions.

8. The left atrial appendage occluder with improved connection method according to claim 1, characterized in that: The connection parts of the sealing part and the anchoring part extend toward each other and pass over the ends of each other.

9. The left atrial appendage occluder with improved connection method according to claim 1, characterized in that: The sealing portion is a sealing disk, and has a predetermined state in which it is not in contact with the anchor portion and a pressed state in which it is in contact with the anchor portion. Relative to the predetermined state, the middle portion of the sealing disk in the pressed state has a deformation that axially protrudes toward the anchor portion.

10. The left atrial appendage occluder with improved connection method according to claim 1, characterized in that: The sealing part includes a disk surface facing away from the anchoring part, a disk bottom facing the anchoring part, and a waist connecting the disk surface and the disk bottom, wherein the disk bottom is flat or the middle part of the disk bottom is convex toward the anchoring part, or the middle part of the disk bottom is convex away from the anchoring part.

11. The left atrial appendage occluder with improved connection method according to claim 10, characterized in that: The sealing portion has a predetermined state in which it is not in contact with the anchor portion and a pressed state in which it is in contact with the anchor portion. In the predetermined state, the diameter of the disk surface is larger than the diameter of the disk bottom.

12. The left atrial appendage occluder with improved connection method according to claim 5, characterized in that: The anchoring portion extends from the connecting piece toward the sealing portion to form an extension section, and the side of the extension section away from the connecting section is turned outward and folded back to the bottom of the sealing portion to form a folded section, which is against the bottom of the sealing portion.

13. The left atrial appendage occluder with improved connection method according to claim 12, characterized in that: The folded-back section is folded inwardly at the bottom position of the sealing portion to form a closing section, and the closing section abuts against the bottom of the sealing portion.

14. The left atrial appendage occluder with improved connection method according to claim 13, characterized in that: The closing section is suspended on the periphery of the extending section or is connected to the extending section.

15. The left atrial appendage occluder with improved connection method according to claim 14, characterized in that: The extension section is tapered, with a large end thereof being away from the connecting piece and being open.

16. The left atrial appendage occluder with improved connection method according to claim 15, characterized in that: The anchor portion has a predetermined state in which it is not pressed against the sealing portion and a pressed state in which it is in contact with the anchor sealing portion. In the predetermined state, the connector is further away from the sealing portion than the closing section in the axial direction of the anchor portion.

17. The left atrial appendage occluder with improved connection method according to claim 16, characterized in that: In the tightened state, the connecting piece is flush with the closing section in the axial direction of the anchoring portion or is further away from the sealing portion than the closing section.

18. The left atrial appendage occluder with improved connection method according to claim 5, characterized in that: The connecting member includes an inner ring and an outer ring that are nested with each other, the bottom of the sealing part has a first convergence, and the radial middle part of the anchoring part has a second convergence. Of the first convergence and the second convergence, one is inserted into and fixed in the inner ring, and the other is inserted into and fixed in the gap between the inner ring and the outer ring.

19. The left atrial appendage occluder with improved connection method according to claim 5, characterized in that: The connecting piece includes an inner ring and an outer ring that are nested with each other, the bottom of the sealing part has a first convergence, and the radial middle part of the anchoring part has a second convergence. Among the first convergence and the second convergence, one is inserted into and fixed in the gap between the inner ring and the outer ring, and the other passes through the inner ring and is fixed with an anti-slip head at the exit end that abuts against the connecting piece.

20. The left atrial appendage occluder with improved connection method according to claim 5, characterized in that: The connector includes a main body with two side-by-side channels, a first convergence at the bottom of the sealing portion, and a second convergence at the radial middle of the anchoring portion. The first convergence and the second convergence respectively pass through the corresponding channels, and anti-slip heads that abut against the main body are fixed at the exit ends.

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