A paravalvular leakage occlusion device

Abstract

The application relates to a paravalvular leakage plugging device applied to a prosthetic valve with an annular body, comprising biodegradable foam attached to at least a section of the outer periphery of the annular body, which is water-swellable and has a first degradation rate; and a film wrapping the biodegradable foam, which is configured as a porous film and has a second degradation rate; when the biodegradable foam swells upon contact with water, the film does not constrain the swelling of the biodegradable foam, and the first degradation rate is different from the second degradation rate. The paravalvular leakage plugging device adopts biodegradable foam to plug the leakage, compared with a traditional metal plugging device, does not cause damage to the heart tissue and the valve, reduces the risk of complications, and meanwhile, the biodegradable foam gradually degrades after completing plugging, so that no residues are left in the human body, further reducing the long-term risk.

Description

Technical Field

[0001] This application relates to the technical field of medical devices, specifically to a paravalvular leak sealing device. Background Technology

[0002] Paravalvular leakage (PVL) is a common complication after artificial valve replacement surgery. It occurs when the suture ring tears from the surrounding tissue, creating a residual leak. It usually develops about one year after surgery. Besides being related to surgical suturing technique and the type of valve used, PVL is also associated with factors such as annular calcification, local tissue fragility, a history of bacterial endocarditis, or systemic malnutrition. The incidence of PVL in the aortic and mitral valves is 0.5–7% and 5%–10%, respectively. Patients with moderate to severe PVL may experience complications such as heart failure and hemolytic anemia.

[0003] The main treatments for PVL include medication and reoperation. Medication primarily uses antibiotics and anticoagulants to prevent infection and blood clots. Reoperation is necessary after the initial surgery if the PVL severely impacts cardiac function to repair the leak. However, both methods have limitations. Medication only relieves symptoms and cannot completely resolve the PVL problem; while reoperation requires another open-heart surgery, which significantly increases the risks and mortality due to postoperative pericardial adhesions and anatomical displacement.

[0004] The minimally invasive percutaneous interventional closure technique, which has developed in recent years, provides a relatively ideal treatment option for PVL (percutaneous transcatheter closure), offering advantages such as minimal trauma, rapid postoperative recovery, and no need for re-opening the chest or cardiopulmonary bypass. Previous clinical applications have demonstrated that transcatheter PVL closure can significantly reduce the severity of PVL, improve clinical symptoms in the short term, and is minimally invasive, safe, and effective. However, there is currently a lack of dedicated PVL closure devices on the market. Commonly used devices include Abbott's vascularplug III, cardiac occluders, and coils, all of which are "off-label" treatments. These devices may not fit the PVL shape well, may compress adjacent tissues, or may interfere with the prosthetic valve, thus affecting valve function. Occlutech's PLD (Paravalvular Device) occluder is a dedicated PVL closure device, but it is more suitable for bioprosthetic PVLs and is prone to interference with mechanical valves. Furthermore, this device is made of nickel-titanium alloy, posing short- and long-term risks such as compression or abrasion of cardiac tissue and nickel ion allergy after implantation. Summary of the Invention

[0005] To overcome at least one of the defects described in the prior art, the purpose of this application is to provide a paravalvular leakage sealing device for use in an artificial valve. The artificial valve has an annular body, wherein the paravalvular leakage sealing device includes:

[0006] A biodegradable foam is attached to at least one section of the outer periphery of an annular body. The biodegradable foam is water-swellable and has a first degradation rate.

[0007] A thin film encapsulating biodegradable foam, the film being constructed as a porous film, and the film exhibiting a second degradation rate;

[0008] When biodegradable foam expands upon contact with water, the membrane does not constrain the expansion of the biodegradable foam, and the first degradation rate differs from the second degradation rate.

[0009] In one embodiment, the inner surface of the film is provided with a sensor facing the biodegradable foam and a wireless communication module. The sensor is configured to detect the force exerted outward by the biodegradable foam during expansion and convert the sensed force into an electrical signal. The wireless communication module transmits the electrical signal to an associated terminal.

[0010] In another embodiment, the sensor and wireless communication module are configured as patches.

[0011] In another embodiment, the sensor and wireless communication module are attached to the inner surface of the film using a biocompatible adhesive.

[0012] In another embodiment, the thin film serves as a substrate in which conductive wires are embedded, and the conductive wires are electrically connected in sequence to the sensor and the wireless communication module.

[0013] In another embodiment, the biodegradable foam is loaded with a drug, which is sealed within the biodegradable foam when it is not in contact with water.

[0014] In another embodiment, the available material for the biodegradable foam is selected from collagen or chitosan; or, the available material for the biodegradable foam is selected from one of the homopolymers polylactic acid, polycaprolactone, polyacetal alcohol, and polyhydroxybutyrate, or a combination of homopolymers.

[0015] In another embodiment, the material available for the thin film is selected from metals or polymers.

[0016] In another embodiment, the film is hydrophilic or hydrophobic.

[0017] In another embodiment, the biodegradable foam is divided into segments along its longitudinal direction, each of the segments having the same or different expansion rates.

[0018] The paravalvular leak closure device of this application uses biodegradable foam as the closure material. Compared with traditional metal occluders, it does not damage adjacent heart tissue and valves, reducing the risk of complications. Furthermore, the biodegradable foam gradually degrades after completing its closure function, leaving no residue in the body, further reducing long-term risks. The flexibility, toughness, and mechanical properties of the biodegradable foam material are similar to those of human perivalvular tissue, resulting in less pressure on heart tissue after implantation. Compared with traditional metal devices, it significantly reduces the risks of abrasion and damage, minimizing the impact on cardiac function. Furthermore, by incorporating sensors, the expansion effect of the foam can be displayed as an electrical signal or a further converted digital signal, facilitating the operator's effective assessment of the closure effect and subsequent decision-making. The combination of biodegradable material properties and intelligent conversion technology effectively improves the effectiveness, safety, and accuracy of PVL closure, significantly reducing the incidence of complications from artificial valve replacement surgery and improving the quality of life for patients with perivalvular disease. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic diagram of a paravalvular leak sealing device applied to the mitral valve location is shown according to one embodiment of this application.

[0021] Figure 2 A schematic diagram of a paravalvular leak sealing device applied to the mitral valve location, according to another embodiment of this application, is shown.

[0022] Figure 3 A schematic diagram of a paravalvular leakage sealing device applied to the mitral valve location is shown according to another embodiment of this application.

[0023] Figure 4 A cross-sectional view showing the relative positions of the biodegradable foam, sensor, and film is shown.

[0024] Figure 5 The schematic diagram of a microelectronic system consisting of a sensor and a wireless communication module is shown.

[0025] Figure 6a and 6b The diagrams show the shapes of the biodegradable foam before and after expansion. Detailed Implementation

[0026] It should be understood that the exemplary embodiments described herein should be considered descriptive only and not for limiting purposes. The description of features or aspects in each exemplary embodiment should generally be considered applicable to similar features or aspects in other exemplary embodiments.

[0027] Reference Figure 1-3 The diagrams illustrate different embodiments of paravalvular leak closure devices applied to the mitral valve location according to this application. PVL problems can occur on one side, opposite sides, or even irregularly distributed multiple sides of the mitral valve, such as the commonly seen crescent-shaped mitral valve (one-sided) PVL, porous PVL, etc. Therefore, this application provides a paravalvular leak closure device applied to an artificial valve 100, wherein the artificial valve 100 has an annular body. The paravalvular leak closure device includes a biodegradable foam 1 and a film 2. The biodegradable foam 1 is attached to at least one segment of the outer periphery of the annular body, for example, as shown in the diagram. Figure 1 As shown, biodegradable foam 1 is attached to one outer side of the annular body; as Figure 2 As shown, biodegradable foam 1 is attached to the opposite outer side of the annular body; as Figure 3 As shown, the biodegradable foam 1 can be clearly divided into several segments 1a, 1b, and 1c, which are connected in series and irregularly attached to multiple sections of the annular body. The specific locations depend on the locations of the various leaks in the porous PVL. The biodegradable foam 1 has the property of expanding upon contact with water. Furthermore, the biodegradable foam 1 also exhibits a first degradation rate.

[0028] On the other hand, the membrane 2 completely encapsulates the biodegradable foam 1. The membrane 2 is constructed as a porous membrane, giving it a loosely configured structure. This configuration allows blood flowing through the mitral valve to pass through the porous membrane 2 and come into contact with the biodegradable foam 1 when the PVL closure device is positioned at the mitral valve location. Ultimately, the biodegradable foam 1 expands under the immersion of blood (water) and seals the multiple leaks in the PVL. Furthermore, similar to the biodegradable foam 1, the membrane 2 also exhibits a second degradation rate.

[0029] The first degradation rate differs from the second degradation rate. The relationship between the first and second degradation rates depends on the specific treatment regimen for the patient; it can be set such that the first degradation rate is greater than the second, or vice versa. Generally, the setting where the first degradation rate is greater than the second is more widely applied, meaning that the biodegradable foam 1 degrades in the patient's body faster than the film 2.

[0030] When the biodegradable foam 1 comes into contact with blood and expands, the membrane 2 does not restrict the expansion of the biodegradable foam 1, allowing it to expand unimpeded to its pre-designed shape. In other words, the presence of the membrane 2 prevents incomplete expansion of the biodegradable foam 1, which could otherwise lead to incomplete sealing of PVL leaks.

[0031] Reference Figure 4-5 A sensor 3 facing the biodegradable foam 1 and a wireless communication module 4 are arranged on the inner surface of the film 2. The sensor 3 is configured to detect the force F exerted outward by the biodegradable foam 1 during expansion and convert the sensed force F into an electrical signal. The force F exerted outward by the biodegradable foam 1 mainly acts on the tissue around the mitral valve, so the sensor 3 facing the biodegradable foam 1 also experiences this force F. The selection of the sensor 3 can be determined based on the expansion rate of the biodegradable foam 1, which will be detailed below. Furthermore, a threshold can be set for the sensor 3, i.e., the deformation of the foam after full expansion is sufficient to trigger the threshold, indicating that the biodegradable foam 1 has completely filled the leak. The wireless communication module 4 transmits the electrical signal to an associated terminal, such as a personal computer, tablet computer, smartphone, etc. In some embodiments, the sensor 3 detects the force F exerted by the biodegradable foam 1, and the resulting signal can also be, in particular, an analog electrical signal. Preferably, both the sensor 3 and the wireless communication module 4 are constructed in the form of patches. The sensor 3, in patch form, and the wireless communication module 4 are attached to the inner surface of the thin film 2 using a biocompatible adhesive. Furthermore, the thin film 2 also serves as a substrate, in which conductive wires (not shown) are embedded. These conductive wires electrically connect the sensor 3 and the wireless communication module 4 sequentially to form a complete microelectronic system / circuit.

[0032] Specifically, a force threshold is set for sensor 3, for example, F. D =2N,F U =10N, if the monitored force value is within F D With F U Between these values, it is evident that the peripheral leak sealing device fits well into the perivalvular tissue; if the monitored force value is consistently greater than F... U If the force value is less than F, it indicates that the paravalvular leak closure device is too large, posing a risk of compressing the perivalvular tissue. Replacing it with a smaller device should be considered. D If the size of the periocular leakage sealing device is too small, there is a risk of it falling off or leaving a leak. It is advisable to consider replacing it with a larger size periocular leakage sealing device, or to further fill it with a smaller size periocular leakage sealing device.

[0033] Furthermore, the analog electrical signals transmitted by the wireless communication module 4 to the associated terminal enable the terminal holder to monitor the expansion performance of the paravalvular leak closure device in real time, thereby inferring the therapeutic effect of the device. In addition, the physical / physiological data characterized by the analog electrical signals can be used for further analysis; however, these functions / designs are not the focus of this application and therefore will not be described in detail herein.

[0034] Reference Figure 6a , 6b The biodegradable foam 1 can be divided into several segments along its longitudinal direction, each segment having the same or different expansion rates. This allows the biodegradable foam 1 to expand to different shapes / sizes when immersed in blood due to their similar or different expansion rates, resulting in a variety of different, possible pre-designed shapes. For example, as... Figure 6a As shown, when biodegradable foam 1 is immersed in blood, the expansion rate of the lower longitudinal section is less than that of the upper longitudinal section, ultimately causing biodegradable foam 1 to expand into a truncated cone shape; alternatively, such as Figure 6b As shown, the biodegradable foam 1 before expansion is a slender cylinder. After expansion, because the expansion rate of the longitudinal segment relative to the middle is less than that of the longitudinal segments relative to the top and bottom, the biodegradable foam 1 eventually expands into a specific shape that converges from both ends (top / bottom) towards the middle. Of course, other pre-designed shapes are also available, such as cylindrical, semi-cylindrical, etc.

[0035] Materials that can be used as biodegradable foam 1 may include natural polymers, such as collagen and chitosan; or synthetic polymers, such as one or more of homopolymers including polylactic acid (PLA), polycaprolactone (PCL), polyacetic acid alcohol (PGA), and polyhydroxybutyrate (PHA), or polymers of the above homopolymers. In one embodiment, biodegradable foam 1 is composed of polylactic acid-glycolic acid copolymer (PLGA). Biodegradable foam 1 made using the above materials can be prepared by physical foaming or by chemical methods, for example, by adding a foaming agent to the above polymers.

[0036] Conversely, the materials that can be used as film 2 may include metals or polymers (e.g., PLA). Film 2 made from the above materials can be processed by an electrospinning process, or it can simply be woven. Combining the materials used and the processing steps of film 2, the resulting film 2 can be either hydrophilic or hydrophobic.

[0037] The density of biodegradable foam 1 can be set at 0.1 g / cm³. 3 up to 0.5 g / cm 3The thickness of the membrane can be set within the range of 1 mm to 5 mm. It is conceivable that, based on the loose configuration of the biodegradable foam 1, there are numerous pores inside. Therefore, preferably, the biodegradable foam 1 can be loaded with medication, which is sealed within it when the biodegradable foam 1 is not in contact with blood. However, when the biodegradable foam 1 comes into contact with blood and begins to expand, the medication originally sealed within is released and then gradually diffuses to the outside of the membrane 2 to treat leaks near the mitral valve. These medications can be heparin-like substances, phosphocholine (MPC)-like substances, collagen components that mimic the function of the human extracellular matrix, etc. Such drug treatment can reduce the risk of thrombosis at the point of contact between the device and human tissue and promote tissue adhesion and rapid endothelialization at the implantation site.

[0038] The paravalvular leak closure device of this application can be used to treat PVL patients, including:

[0039] S1. Select a suitable biodegradable foam 1 material and prepare a biodegradable foam 1 with mechanical properties (especially compressive strength, elastic modulus, etc.) that are closest to human tissue through physical / chemical foaming. In this process, it is necessary to measure key performance parameters such as expansion rate, thermal expansion coefficient, and elastic modulus of the prepared biodegradable foam 1, and evaluate its deformation degree and mechanical response when subjected to different degrees of tissue compression under human physiological environment. According to the common PVL size in clinical practice, cut the prepared biodegradable foam 1 or further process it into cross-sections such as circular, semi-circular, and slit-shaped, with diameters covering the common PVL size and shape.

[0040] S2. Based on the measured expansion rate and mechanical response under specific conditions of the biodegradable foam 1, a suitable force-to-electrical conversion sensor 3 is selected, preferably a self-powered polymer sensor 3, whose sensitivity is suitable for identifying the force applied by the periplocellar leakage sealing device and for converting the identified force into a voltage / current signal, such as... Figure 5 As shown;

[0041] S3. Based on the size and shape of the biodegradable foam 1, a certain number of sensors 3 are arranged at the location where the peripheral leakage sealing device directly contacts the heart tissue, and they are numbered according to their location so as to identify the heart tissue location that bears the force later.

[0042] S4. Based on the characteristics of the analog electrical signal output by sensor 3, select the wireless communication module 4 that can identify the electrical signal;

[0043] S5. Select a suitable thin film 2 as a substrate, preferably a polymer material that can embed conductive wires, such as polylactic acid, and attach the sensor 3 and wireless communication module 4 to the substrate (i.e., thin film 2) to form a microelectronic system.

[0044] S6. The unexpanded paravalvular leak sealing device is delivered to the leak site via the sealing device delivery system. The paravalvular leak sealing device gradually expands by absorbing blood in the human body. After contacting the perivalvular tissue, it generates pressure, and when the pressure value reaches the triggerable force-to-electric conversion threshold of sensor 3, it generates an analog electrical signal. The wireless communication module 4 further transmits the analog electrical signal to terminals outside the human body. These terminals perform signal conversion, specifically restoring the analog electrical signal to a value that is easy for the operator to understand intuitively. This allows monitoring of the expansion effect of the paravalvular leak sealing device for subsequent scheme judgment. The conventional sealing device delivery system may include catheters, delivery devices, etc. The diameter of the catheter can be selected according to the size of the leak, usually between 1mm and 5mm.

[0045] S7. If the biodegradable foam 1 does not completely fill the leak, repeat S2-S6 above until the biodegradable foam 1 completely fills the leak. Then, remove the delivery system to complete the implantation of the artificial valve and the paravalvular leak sealing device.

[0046] After completing its sealing function, the biodegradable foam 1 will gradually degrade. This process can be completed within 6-12 months, depending on the properties of the material and the size of the leak. During degradation, the biodegradable foam 1 will gradually shrink and eventually disappear completely, leaving no residue in the body. Similarly, the film 2 will also gradually degrade within the patient's body. As mentioned above, the relationship between the first and second degradation rates depends on the specific treatment plan for the individual patient.

[0047] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A paravalvular leakage sealing device, applied to an artificial valve, wherein the artificial valve has an annular body, characterized in that, The periocular leakage sealing device includes: A biodegradable foam, wherein the biodegradable foam is attached to at least one segment of the outer periphery of the annular body, the biodegradable foam is water-swellable, and the biodegradable foam has a first degradation rate; A thin film encapsulating the biodegradable foam, the thin film being constructed as a porous film and having a second degradation rate; When the biodegradable foam expands upon contact with water, the film does not restrict the expansion of the biodegradable foam, and the first degradation rate is different from the second degradation rate.

2. The periploval leakage sealing device according to claim 1, characterized in that, The inner surface of the film is provided with a sensor facing the biodegradable foam and a wireless communication module. The sensor is configured to detect the force exerted outward by the biodegradable foam during expansion and convert the sensed force into an electrical signal. The wireless communication module transmits the electrical signal to an associated terminal.

3. The periocular leakage sealing device according to claim 2, characterized in that, The sensor and the wireless communication module are configured as patches.

4. The periocular leakage sealing device according to claim 3, characterized in that, The sensor and the wireless communication module are attached to the inner surface of the film using a biocompatible adhesive.

5. The periocular leakage sealing device according to claim 4, characterized in that, The thin film serves as a substrate, in which conductive wires are embedded, and the conductive wires are electrically connected in sequence to the sensor and the wireless communication module.

6. The periocular leakage sealing device according to claim 1, characterized in that, The biodegradable foam contains a drug that is sealed within it when it is not in contact with water.

7. The periploval leakage sealing device according to claim 1, characterized in that, The biodegradable foam may be made from materials selected from collagen or chitosan; or, the biodegradable foam may be made from materials selected from homopolymer polylactic acid, polycaprolactone, polyacetal, or polyhydroxybutyrate.

8. The periocular leakage sealing device according to claim 1, characterized in that, The available materials for the thin film are selected from metals or polymers.

9. The periploval leakage sealing device according to claim 8, characterized in that, The film is either hydrophilic or hydrophobic.

10. The periploval leakage sealing device according to claim 1, characterized in that, The biodegradable foam is divided into several segments along its longitudinal direction, each of which has the same or different expansion rates.

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