A biodegradable left atrial appendage occluder

Abstract

This invention discloses a biodegradable left atrial appendage occlusion device, belonging to the field of interventional medical device technology. It includes an occlusion part, a connecting part, and a fixing part. The occlusion part is connected to the fixing part via the connecting part. The fixing part includes a first occlusion membrane, a first support and fixing mechanism, and a second support and fixing mechanism. The first occlusion membrane is connected to the connecting part, and both the first and second support and fixing mechanisms are disposed inside the first occlusion membrane and connected to the connecting part. This invention, through the combined design of the first and second support and fixing mechanisms, solves the problems of current occlusion devices failing to adhere well to the inner wall of the left atrial appendage, resulting in poor fixation, and the potential for concentrated pressure during fixation that could lead to abrasion or puncture of the left atrial appendage wall. It achieves a superior fixation effect to the inner wall of the left atrial appendage.

Description

Technical Field

[0001] This invention belongs to the field of interventional medical device technology, specifically relating to a biodegradable left atrial appendage occluder. Background Technology

[0002] Atrial fibrillation (AF) is one of the most common arrhythmias. Besides the discomfort caused by palpitations, the most significant danger of AF is the occurrence of complications such as thromboembolism. Therefore, the prevention and treatment of stroke caused by thrombosis due to AF is of great clinical importance.

[0003] Currently, methods for preventing and treating thrombotic events in atrial fibrillation include surgery, drug therapy, and interventional treatment. Surgical methods are not widely used due to their high invasiveness and risks. Drug therapy typically involves long-term oral anticoagulants, but these carry the risk of bleeding. Based on the problems with these two methods, an interventional treatment method has been developed in recent years both domestically and internationally. Specifically, a specially designed left atrial appendage occluder is implanted into the left atrial appendage through a thin catheter to block it, thereby preventing and treating thrombotic events and stroke in patients with atrial fibrillation. This treatment method, due to its advantages of minimal invasiveness, low risk, rapid recovery, and good efficacy, is gradually becoming a reliable treatment for preventing and treating stroke caused by atrial fibrillation.

[0004] Left atrial appendage occlusion devices primarily comprise two core functions: left atrial appendage occlusion and device fixation. Currently, commonly used left atrial appendage occlusion devices are mainly divided into single-disc and double-disc types. Single-disc occlusion devices require a longer axial dimension to ensure effective contact and fixation with the left atrial appendage wall. However, this increased size makes insertion and deployment difficult, hindering surgical operation. Furthermore, the fixation and occlusion effectiveness of a single-disc device depends heavily on the fit between the occlusion contour and the atrial appendage wall. Due to the irregular shape and individual differences within the left atrial appendage, ensuring a good fit is challenging. Double-disc occlusion devices, on the other hand, offer superior fixation and occlusion compared to single-disc devices.

[0005] The invention patent with authorization announcement number CN112315523B discloses a sealing device, including a sealing part and a fixing part connected to the sealing part. The fixing part includes a flipping rod and a support net connected in series along its axial direction. The proximal end of the support net is connected to the distal end of the flipping rod. The support net is woven into a mesh shape by first braided filaments. The flipping rod is made into a rod shape by cutting a tubular part or by winding multiple second braided filaments. During the unfolding of the fixing part, the distal end of the flipping rod extends toward the distal end and then flips outward toward the sealing part. At least a portion of the support net forms the sidewall of the fixing part after the fixing part is unfolded. Although the technical solution uses a mesh-like support net woven from the first braided filament to maintain a large contact area with the left atrial appendage wall after the fixing part is released, making the pressure exerted on the wall by the fixing part more even and dispersed, thus avoiding stress concentration, the interior of the left atrial appendage is irregularly shaped and has individual differences. Therefore, the support net with the smooth arc structure cannot fit well with the inner wall of the left atrial appendage, thus affecting the fixation effect of the occluder. Moreover, the anchor in this solution needs to penetrate into the body tissue for further fixation, which may cause damage to the atrial appendage wall or even puncture, resulting in surgical accidents.

[0006] The invention patent with authorization announcement number CN110960282B discloses a left atrial appendage occlusion device. Although the technical solution uses the design of an elastic fixing arc and a concave deformation part to make the deformation resistance of the first fixing strip small and the deformation resistance of the second solid strip large, dividing the fixing part into two parts with different deformation resistance in the circumferential direction, thus increasing the gripping force of the fixing part at the opening of the left atrial appendage through the part with larger deformation resistance, and deforming through the part with smaller deformation resistance to adapt to different sizes of the opening of the left atrial appendage, in the actual fixing process, it is only fixed by the elastic fixing arc and the concave deformation part adhering to the inner wall of the left atrial appendage, and cannot completely adhere to the inner wall of the left atrial appendage, resulting in a less than ideal fixing effect. Moreover, because the fixing is only achieved by adhering to the inner wall of the left atrial appendage through the elastic fixing arc and the concave deformation part, the compressive force is concentrated, which may lead to abrasion or puncture of the cavity wall of the left atrial appendage and adverse consequences.

[0007] Based on the structural analysis of the existing dual-disc occluder, it can be seen that the existing dual-disc occluder has the problem that it cannot fit well with the inner wall of the left atrial appendage, resulting in poor fixation. In addition, the compression force may be concentrated during the fixation process, which may cause abrasion or puncture of the left atrial appendage cavity wall. Based on this problem, the present invention designs a biodegradable left atrial appendage occluder that can be well fixed with the inside of the left atrial appendage. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a biodegradable left atrial appendage occluder.

[0009] The biodegradable left atrial appendage occlusion device provided by this invention, through the design of two support and fixation mechanisms, not only provides excellent support for the occlusion membrane, but also, through the multi-arc bending design of the support mechanism, allows for excellent adhesion to the inner wall of the left atrial appendage after the occlusion membrane degrades. Furthermore, the design of the adsorption and fixation structure enables negative pressure adsorption with the inner wall of the left atrial appendage, further enhancing the fixation effect. Moreover, by designing the occlusion membrane as a biodegradable structure, after the occlusion membrane degrades, the support and fixation mechanism can further unfold under the force of its own restorative elastic deformation, making full contact with the inner wall of the left atrial appendage and achieving stable fixation.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0011] This invention discloses a biodegradable left atrial appendage occlusion device, comprising an occlusion part, a connecting part, and a fixing part. The occlusion part is connected to the fixing part through the connecting part. The fixing part includes a first occlusion membrane, a first support and fixing mechanism, and a second support and fixing mechanism. The first occlusion membrane is connected to the connecting part. The first support and fixing mechanism and the second support and fixing mechanism are both disposed inside the first occlusion membrane and are both connected to the connecting part. The first occlusion membrane is made of a bioabsorbable material.

[0012] Preferably, the first support and fixing mechanism includes an anchor and a plurality of first support and fixing rods. The plurality of first support and fixing rods are spaced apart in the circumferential direction inside the first sealing membrane, and one end of each first support and fixing rod is connected to the end face of the connecting part near the fixing part, and the other end is connected to the anchor.

[0013] Preferably, each of the first support fixing rods is an elastic rod with multiple arc-shaped portions.

[0014] Preferably, the second support and fixing mechanism includes a plurality of second support and fixing rods, an auxiliary support and fixing mechanism, and an adsorption and fixing mechanism. The plurality of second support and fixing rods are spaced apart along the circumferential direction inside the first sealing membrane. Each second support and fixing rod is disposed between two adjacent first support and fixing rods. One end of each second support and fixing rod is connected to the end face of the connecting part near the fixing part, and the other end is connected to the corresponding adsorption and fixing mechanism. Each auxiliary support and fixing mechanism is connected to the corresponding second support and fixing rod.

[0015] Preferably, each of the second support fixing rods includes a first connecting rod and a second connecting rod. One end of the first connecting rod is connected to the end face of the connecting part near the fixing part, and the other end is connected to the second connecting rod. The movable end of the second connecting rod is connected to the corresponding adsorption fixing mechanism.

[0016] Preferably, the first connecting rod is an elastic rod with multiple different curvatures, and the second connecting rod is an elastic rod with a multi-segment wave-shaped structure.

[0017] Preferably, each auxiliary support fixing mechanism includes two auxiliary connecting rods and two auxiliary support rods. The two auxiliary connecting rods are symmetrically arranged on the outer surface of the second connecting rod, and the two auxiliary support rods are respectively connected to the movable end of the corresponding auxiliary connecting rod.

[0018] Preferably, each of the auxiliary connecting rods is an elastic rod with multiple different curvatures, and each auxiliary support rod is an elastic rod with a multi-segment wave-shaped structure.

[0019] Preferably, each adsorption and fixing mechanism includes a suction cup and multiple annular grooves. The suction cup is connected to the movable end of the second connecting rod, and the multiple annular grooves are circumferentially formed on the inner surface of the suction cup.

[0020] Preferably, a first one-way valve and a second one-way valve are respectively provided inside the connecting part and inside the suction cup connecting end. The second connecting rod is a hollow structure, and both ends of the second connecting rod are respectively connected to the connecting part and the suction cup.

[0021] Compared with the prior art, the advantages of this invention are as follows:

[0022] (1) The present invention provides a relatively stable support and fixation effect for the occlusion membrane through the design of the first support and fixation mechanism, forming a fixed foundation. Furthermore, by designing the first support and fixation rod as a structure with multiple arc-shaped parts, the first support and fixation rod can be unfolded to initially fit against the inner wall of the left atrial appendage after the first occlusion membrane degrades, thus improving the support and fixation effect. Moreover, by designing the first occlusion membrane as a biodegradable material, the present invention enables the first and second support and fixation rods to unfold again after the first occlusion membrane degrades, further improving the fixation effect with the inner wall of the left atrial appendage.

[0023] (2) Through the design of the second support and fixing mechanism, since the end of the second support and fixing rod away from the connecting part is located on the outside of the sealing membrane, after the sealing device of the present invention is removed from the sheath, the outer end of the second support and fixing rod will be extended outward and fully contact the inner wall of the left atrial appendage under the force of its own restoring elastic deformation, thus improving the support and fixing effect.

[0024] (3) By designing the first connecting rod as a structure with multiple different curvatures, the present invention can meet the space requirements of the folded state and fully maintain its outward expansion force after unfolding, thereby improving its fit with the atrial appendage wall; and by designing the second connecting rod as a structure with multiple wave-shaped segments, it can fit well with the shape of the inner wall of the left atrial appendage, thereby improving the support and fixation effect.

[0025] (4) By setting an auxiliary connecting rod at the second connecting rod and designing the auxiliary connecting rod as a structure with multiple different curvatures, the present invention can not only meet the space requirements of the folded state, but also fully maintain its outward expansion force after unfolding, and improve its fit with the atrial appendage wall; at the same time, through the design of the auxiliary support rod, it can further fit with the shape of the inner wall of the left atrial appendage. When the biodegradable occlusion membrane is present, the auxiliary support rod supports the first occlusion membrane, greatly improving the fit of the first occlusion membrane and reducing the gap with the ventricular wall. After the occlusion membrane degrades, the second support fixing rod loses the constraint of the first occlusion membrane and extends further outward, enhancing the bonding strength with the ventricular wall. On the basis of the extension of the second support fixing rod, the auxiliary support rod further improves the fit with the inner wall of the left atrial appendage through its own extension, and strengthens the fixing effect.

[0026] (5) Through the design of the adsorption and fixation mechanism, the present invention can simultaneously perform negative pressure adsorption on the suction cup when the blood in the left atrial appendage is suctioned under negative pressure after the occluder is initially installed, so that the suction cup is attracted to the negative pressure inside the left atrial appendage, resulting in a better fixation effect.

[0027] (6) The invention, through the design of the first connecting rod, the second connecting rod, the second support fixing rod and the auxiliary support rod with multiple bends, can fit well with the inner wall of the left atrial appendage, so that there will be no problem of concentrated pressure, which would cause abrasion or puncture of the left atrial appendage cavity wall. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the biodegradable left atrial appendage occluder provided in an embodiment of the present invention;

[0029] Figure 2 A side view of the biodegradable left atrial appendage occluder provided in an embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the biodegradable left atrial appendage occluder provided in an embodiment of the present invention with the first occlusion membrane removed.

[0031] Figure 4 This is a schematic diagram of the connection structure between the connecting part and the first support fixing mechanism, the second support fixing mechanism and the auxiliary support fixing mechanism in an embodiment of the present invention.

[0032] Figure 5 This is a schematic diagram of the connection structure between the connecting part and the first support and fixing mechanism in an embodiment of the present invention;

[0033] Figure 6 This is a schematic diagram of the connection structure of the connecting part and the second support fixing mechanism in an embodiment of the present invention;

[0034] Figure 7 This is a schematic diagram of the structure of the second support and fixing mechanism in an embodiment of the present invention;

[0035] Figure 8 This is a schematic diagram of the structure of the first support fixing rod in an embodiment of the present invention;

[0036] Figure 9 This is a schematic diagram of the structure of the second support fixing rod in an embodiment of the present invention;

[0037] Figure 10 This is a schematic diagram of the adsorption and fixation mechanism in an embodiment of the present invention;

[0038] Figure 11 This is a cross-sectional view of the adsorption and fixation mechanism along the AA direction in an embodiment of the present invention;

[0039] Figure 12 for Figure 11 A magnified view of part A in the middle;

[0040] Figure 13 This is a schematic diagram of the biodegradable left atrial appendage occluder in use according to an embodiment of the present invention;

[0041] Figure 14 This is a diagram showing the state of the biodegradable left atrial appendage occluder provided in this embodiment of the invention when it is inside the left atrial appendage.

[0042] In the diagram: 1. Sealing part; 2. Connecting part; 3. Fixing part; 31. First sealing membrane; 32. First support and fixing mechanism; 321. Anchor; 322. First support and fixing rod; 33. Second support and fixing mechanism; 331. Second support and fixing rod; 3311. First connecting rod; 3312. Second connecting rod; 332. Auxiliary support and fixing mechanism; 3321. Auxiliary connecting rod; 3322. Auxiliary support rod; 333. Adsorption and fixing mechanism; 3331. Suction cup; 3332. Annular groove; 4. First connecting hole; 5. Second connecting hole; 6. Left atrial appendage. Detailed Implementation

[0043] The following will be described in conjunction with embodiments of the present invention. Figures 1 to 14 The technical solutions in the embodiments of the present invention are clearly and completely described herein. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0044] Example 1

[0045] like Figures 1 to 6 , Figure 13 and Figure 14As shown, this embodiment of the invention provides a biodegradable left atrial appendage occlusion device, including an occlusion part 1, a connecting part 2, and a fixing part 3. The occlusion part 1 is connected to the fixing part 3 through the connecting part 2. The fixing part 3 includes a first occlusion membrane 31, a first support and fixing mechanism 32, and a second support and fixing mechanism 33. The first occlusion membrane 31 is connected to the connecting part 2. The first support and fixing mechanism 32 and the second support and fixing mechanism 33 are both disposed inside the first occlusion membrane 31 and are both connected to the connecting part 2. The occlusion part 1 and the connecting part 2 in this embodiment of the invention can refer to existing technologies. This invention does not involve improving the structure of the occlusion part 1 and the connecting part 2, so the structure of the occlusion part 1 and the connecting part 2 will not be described in detail in this embodiment. The first occlusion membrane 31 in this embodiment of the invention is made of a bioabsorbable material, which can be any one of polylactic acid, poly(lactic-co-glycolic acid), or poly(p-dioxane), or other existing bioabsorbable materials. The present invention, through the biodegradable design of the first occlusion membrane 31, enables the left atrial appendage function to be restored after the patient's condition is controlled and the factors causing thrombosis in the left atrial appendage are eliminated, as the first occlusion membrane 31 degrades, allowing the human body to return to its original state.

[0046] In this embodiment of the invention, the first support and fixing mechanism 32 includes an anchor 321 and a plurality of first support and fixing rods 322. The plurality of first support and fixing rods 322 are spaced apart along the circumferential direction inside the first sealing membrane 31, and one end of each first support and fixing rod 322 is connected to the end face of the connecting part 2 near the fixing part 3, and the other end is connected to the anchor 321. Each first support and fixing rod 322 is an elastic rod with multiple arc-shaped portions. In this embodiment, the first support fixing rod 322 is made of shape memory alloy. This material design allows the first support fixing rod 322 to be folded and retracted under external force, and to unfold and restore its original shape when the external force is removed. Preferably, there are four first support fixing rods 322. The anchoring member 321 in this embodiment has a spherical, elliptical, or oblate structure, or other structures with smooth surfaces. In this embodiment, a spherical structure is preferred. Specifically, multiple first connecting holes 4 are provided on the end face of the connecting part 2 near the fixing part 3. The design of the first connecting holes 4 facilitates the connection between the first support fixing rod 322 and the connecting part 2. This embodiment, through the combined design of the anchoring member 321 and multiple first support fixing rods 322, forms a mesh structure. After the occluder detaches from the sheath, it can unfold to provide stable support for the first sealing membrane 31. Furthermore, to ensure that the first support fixing rod 322 can adapt to the space requirements of the folded state, this embodiment further designs the first support fixing rod 322 as a curved rod structure with multiple arc-shaped portions, such as… Figure 8As shown, this design allows it to meet the space requirements of the folded state, and through the design of the special structure, it can fully maintain the outward expansion force after the first support fixing rod 322 is unfolded, thereby improving the fit with the inner wall of the left atrial appendage 6.

[0047] In this embodiment of the invention, the second support and fixing mechanism 33 includes a plurality of second support and fixing rods 331, an auxiliary support and fixing mechanism 332, and an adsorption and fixing mechanism 333. The plurality of second support and fixing rods 331 are spaced apart along the circumferential direction inside the first sealing membrane 31. Each second support and fixing rod 331 is disposed between two adjacent first support and fixing rods 322, and one end of each second support and fixing rod 331 is connected to the end face of the connecting part 2 near the fixing part 3, and the other end is connected to the corresponding adsorption and fixing mechanism 333. Each auxiliary support and fixing mechanism is connected to the corresponding second support and fixing rod 331. In this embodiment of the invention, the second support fixing rod 331 and the auxiliary support fixing mechanism 332 are made of shape memory alloy. This material design allows the second support fixing rod 331 and the auxiliary support fixing mechanism 332 to be folded and retracted under external force, and to unfold and restore their original shape when the external force is removed. Specifically, the end face of the connecting part 2 near the fixing part 3 has multiple second connecting holes 5 that communicate with the internal channel of the connecting part 2. The design of the second connecting holes 5 facilitates the connection between the second support fixing rod 331 and the connecting part 2. In this embodiment of the invention, the number of the second support fixing rod 331, the auxiliary support fixing mechanism 332, and the adsorption fixing mechanism 333 are preferably four. However, in specific designs, the number can be adjusted according to actual conditions. The number of the second support fixing rods 331, auxiliary support fixing mechanism 332, and adsorption fixing mechanism 333 is designed to be 8 or 12. Since there are multiple second support fixing rods 331, after the multiple second support fixing rods 331 in this embodiment of the invention are detached from the sheath, they form a diverging petal shape. Therefore, the combined design of the second support fixing rods 331 and the auxiliary support fixing mechanism 332 can provide good support for the first occlusion membrane 31. After the first occlusion membrane 31 degrades, the multiple second support fixing rods 331 can better fit with the left atrial appendage, disperse the extrusion pressure, and because they can fit and fix well with the left atrial appendage, the second support fixing rods 331 will not easily detach from the left atrial appendage, thereby improving safety and providing a better occlusion effect.

[0048] Example 2

[0049] To further improve the fixation effect between the occluder and the left atrial appendage provided by the present invention, the embodiments of the present invention, based on Embodiment 1, further design the structure of the second support fixing rod 331, specifically as follows:

[0050] like Figure 9As shown in the embodiment of the present invention, each second support fixing rod 331 includes a first connecting rod 3311 and a second connecting rod 3312. One end of the first connecting rod 3311 is connected to the end face of the connecting part 2 near the fixing part 3, and the other end is connected to the second connecting rod 3312. The movable end of the second connecting rod 3312 is connected to the corresponding adsorption fixing mechanism 333. In a specific design, one end of the first connecting rod 3311 is connected to the corresponding second connecting hole 7, while the movable end of the second connecting rod 3312 is located outside the first sealing membrane 31. When the occluder in this embodiment of the present invention is removed from the sheath, since the movable end of the second connecting rod 3312 loses the limiting effect of the sheath, the second connecting rod 3312 expands outward under the force of its own restoring elastic deformation and contacts the inner wall of the left atrial appendage. Since it is not limited by the first sealing membrane 31, its outward expansion is greater than that of the first connecting rod 3311. Therefore, through sufficient contact with the inner wall of the left atrial appendage, it can achieve good fixation with the inner wall of the left atrial appendage.

[0051] In order to ensure that the first connecting rod 3311 can adapt to the spatial requirements of the folded state, this embodiment of the invention further designs the first connecting rod 3311 as a curved rod-like structure with multiple different curvatures, so that it can meet the spatial requirements of the folded state. Through the design of the above-mentioned special structure, the outward expansion force can be fully maintained after the first connecting rod 3311 is unfolded, improving the fit with the inner wall of the left atrial appendage. Furthermore, in order to ensure that the second connecting rod 3312 can fit well with the shape of the inner wall of the left atrial appendage, this embodiment of the invention further designs the second connecting rod 3312 as a curved rod-like structure with multiple wavy sections, further conforming it to the shape of the inner wall of the left atrial appendage, increasing the fit with the shape of the inner wall of the left atrial appendage, and achieving good fixation with the inner wall of the left atrial appendage.

[0052] Example 3

[0053] To further improve the fixation effect of the occluder to the left atrial appendage and to meet the requirements of the occlusion state, this embodiment of the invention, based on Embodiments 1 and 2, further designs the structure of the auxiliary support and fixation mechanism 332, specifically as follows:

[0054] like Figure 7As shown, each auxiliary support fixing mechanism 332 includes two auxiliary connecting rods 3321 and two auxiliary support rods 3322. The two auxiliary connecting rods 3321 are symmetrically arranged on the outer surface of the second connecting rod 3312, and the two auxiliary support rods 3322 are respectively connected to the movable ends of the corresponding auxiliary connecting rods 3321. Through the combined design of the auxiliary connecting rods 3321 and the auxiliary support rods 3322, this embodiment of the invention enables simultaneous auxiliary support from the first support fixing rod 322 and the second support fixing rod 331 when supporting the first occlusion membrane 31. This not only improves the support effect but also disperses the compressive force on the inner wall of the left atrial appendage after the first occlusion membrane 31 degrades.

[0055] In this invention, each auxiliary connecting rod 3321 is an elastic rod with multiple different curvatures, and each auxiliary support rod 3322 is an elastic rod with multiple wave-shaped structures.

[0056] To ensure that the auxiliary connecting rod 3321 can adapt to the spatial requirements of the folded state, this embodiment of the invention further designs the auxiliary connecting rod 3321 as a curved rod-like structure with multiple different curvatures. This allows it to meet the spatial requirements of the folded state. Furthermore, through this special structural design, the auxiliary connecting rod 3321 can maintain its outward expansion force after unfolding, improving its fit with the inner wall of the left atrial appendage. To ensure that the auxiliary support rod 3322 can fit well with the shape of the inner wall of the left atrial appendage, this embodiment of the invention further designs the auxiliary support rod 3322 as a curved rod-like structure with multiple wavy sections. This further conforms to the shape of the inner wall of the left atrial appendage, increasing the fit and achieving good fixation.

[0057] Example 4

[0058] To further improve the fixation effect between the occluder and the left atrial appendage provided by the present invention, the present invention further designs the structure of the adsorption fixation mechanism 333 based on Embodiments 1 and 2, specifically as follows:

[0059] like Figures 10 to 12As shown, the adsorption and fixation mechanism 333 in this embodiment of the invention includes a suction cup 3331 and multiple annular grooves 3332. The suction cup 3331 is connected to the movable end of the second connecting rod 3312, and the multiple annular grooves 3332 are circumferentially formed on the inner surface of the suction cup 3331. A first one-way valve and a second one-way valve are respectively provided inside the connecting part 2 and inside the connecting end of the suction cup 3331. The second connecting rod 3312 has a hollow structure, and its two ends are respectively connected to the connecting part 2 and the suction cup 3331. In this embodiment of the invention, the design of the suction cup 3331 enables negative pressure adsorption between the suction cup 3331 and the inner wall of the left atrial appendage, resulting in better fixation. The design of the multiple annular grooves 3332 increases the contact friction with the inner wall of the left atrial appendage, further improving its fixation degree. The first one-way valve and the second one-way valve maintain a negative pressure state inside the suction cup, maintaining the adsorption effect.

[0060] During the left atrial appendage occlusion process provided in this embodiment of the invention, there must be no blood remaining inside the occluder. Otherwise, after the first occlusion membrane 31 degrades, a thrombus will form directly. Therefore, a first one-way valve needs to be set in the connecting part 2. After the initial placement of the occluder is completed, the blood remaining inside the left atrial appendage is suctioned by negative pressure to ensure that there is no residual blood inside. While suctioning the blood, the suction cup 3331 is also suctioned by negative pressure through the internal channel of the second connecting rod 3312, so that the suction cup 3331 is suctioned to the inner wall of the left atrial appendage by negative pressure, thereby improving the fixation effect with the left atrial appendage.

[0061] When the biodegradable left atrial appendage occluder provided in this embodiment of the invention is needed to occlude the left atrial appendage, the existing left atrial appendage occluder's delivery device is first connected to the occlusion part 1 and inserted into the sheath. When the left atrial appendage occluder separates from the sheath, the occlusion part 1 unfolds. Simultaneously, the first occlusion membrane 31 unfolds outward along with the first support fixing rod 322 and the second support fixing rod 331, so that the first occlusion membrane 31 adheres and is fixed to the inner wall of the left atrial appendage. At this time, the second connecting rod 3312, under the force of its own restoring elastic deformation, It unfolds outward and contacts and fixes itself to the inner wall of the left atrial appendage. At this time, negative pressure is applied to aspirate the blood retained inside the left atrial appendage to ensure that there is no residual blood. While aspirating the blood, the suction cup 3331 is also negatively adsorbed through the internal channel of the second connecting rod 3312, so that the suction cup 3331 is negatively adsorbed to the inner wall of the left atrial appendage, further improving the fixation effect with the left atrial appendage. Moreover, as the first sealing membrane 31 degrades, it unfolds again as the first sealing membrane 31 degrades, further improving the fixation effect with the inner wall of the left atrial appendage.

[0062] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A biodegradable left atrial appendage occlusion device, comprising an occlusion part (1), a connecting part (2), and a fixing part (3), wherein the occlusion part (1) is connected to the fixing part (3) via the connecting part (2), characterized in that, The fixing part (3) includes a first sealing membrane (31), a first supporting fixing mechanism (32), and a second supporting fixing mechanism (33). The first sealing membrane (31) is connected to the connecting part (2). The first supporting fixing mechanism (32) and the second supporting fixing mechanism (33) are both disposed inside the first sealing membrane (31). The first supporting fixing mechanism (32) and the second supporting fixing mechanism (33) are both connected to the connecting part (2). The first sealing membrane (31) is made of bioabsorbable material. The first support and fixing mechanism (32) includes an anchor (321) and a plurality of first support and fixing rods (322). The plurality of first support and fixing rods (322) are spaced apart in the circumferential direction inside the first sealing membrane (31), and one end of each first support and fixing rod (322) is connected to the end face of the connecting part (2) near the fixing part (3), and the other end is connected to the anchor (321). Each of the first support fixing rods (322) is an elastic rod with multiple arcuate portions; The second support and fixing mechanism (33) includes a plurality of second support and fixing rods (331), an auxiliary support and fixing mechanism (332), and an adsorption and fixing mechanism (333). The plurality of second support and fixing rods (331) are spaced apart in the circumferential direction inside the first sealing membrane (31). Each second support and fixing rod (331) is disposed between two adjacent first support and fixing rods (322). One end of each second support and fixing rod (331) is connected to the end face of the connecting part (2) near the fixing part (3), and the other end is connected to the corresponding adsorption and fixing mechanism (333). Each auxiliary support and fixing mechanism is connected to the corresponding second support and fixing rod (331). Each of the second support fixing rods (331) includes a first connecting rod (3311) and a second connecting rod (3312). One end of the first connecting rod (3311) is connected to the end face of the connecting part (2) near the fixing part (3), and the other end is connected to the second connecting rod (3312). The movable end of the second connecting rod (3312) is connected to the corresponding adsorption fixing mechanism (333). The first connecting rod (3311) is an elastic rod with multiple different curvatures, and the second connecting rod (3312) is an elastic rod with multiple wave-shaped structures. Each auxiliary support fixing mechanism (332) includes two auxiliary connecting rods (3321) and two auxiliary support rods (3322). The two auxiliary connecting rods (3321) are symmetrically arranged on the outer side of the second connecting rod (3312), and the two auxiliary support rods (3322) are respectively connected to the movable end of the corresponding auxiliary connecting rod (3321). Each of the auxiliary connecting rods (3321) is an elastic rod with multiple different curvatures, and each auxiliary support rod (3322) is an elastic rod with a multi-segment wave-shaped structure.

2. The biodegradable left atrial appendage occlusion device as described in claim 1, characterized in that, Each adsorption fixing mechanism (333) includes a suction cup (3331) and multiple annular grooves (3332). The suction cup (3331) is connected to the movable end of the second connecting rod (3312), and the multiple annular grooves (3332) are circumferentially opened on the inner surface of the suction cup (3331).

3. The biodegradable left atrial appendage occlusion device as described in claim 2, characterized in that, The interior of the connecting part (2) and the interior of the suction cup (3331) are respectively provided with a first one-way valve (4) and a second one-way valve (5). The second connecting rod (3312) is a hollow structure, and the two ends of the second connecting rod (3312) are respectively connected to the connecting part (2) and the suction cup (3331).

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