medical devices

Abstract

This invention relates to a medical device for intercepting obstructions in blood vessels, characterized by comprising an interception section, a balancing section, and a connecting section. The interception section includes anchors for anchoring the interception mesh into the blood vessel. The connecting section includes a plurality of biodegradable connecting wires, one end of each connecting wire being connected to the end of the interception section away from the anchor, and the other end being connected to the balancing section. This medical device is easily recyclable.

Description

Technical Field

[0001] This invention relates to the field of interventional medical devices, and in particular to a medical device. Background Technology

[0002] This section provides only background information relevant to this disclosure and is not necessarily prior art.

[0003] Thromboembolism is a common and potentially fatal emergency, such as deep vein thrombosis (DVT), with an incidence rate of 4% to 20%. If DVT is not removed promptly, it can lead to post-thrombotic syndrome, characterized by significant swelling, darkening, and skin ulceration at the affected site, severely impacting the patient's quality of life. Therefore, timely removal of DVT to prevent pulmonary embolism remains a major challenge.

[0004] Clinically, temporary medical devices are often implanted in blood vessels to intercept thrombi. However, during use, to ensure stable anchoring of the device within the vessel, the device must have a sufficiently large contact area with the vessel wall to maintain a supporting position and provide adequate radial support. This inevitably leads to endothelial cell migration, making retrieval difficult. To mitigate endothelial cell migration, structural design is often employed to reduce the contact area between the device and the vessel wall. However, reducing the contact area can decrease the device's stability within the vessel. Under the impact of blood flow or vascular tortuosity, the device is prone to tilting, causing the retrieval components to adhere to the vessel wall, which in turn also complicates retrieval. Summary of the Invention

[0005] Therefore, it is necessary to provide a medical device that is easy to recycle.

[0006] A medical device for intercepting obstructions in a blood vessel includes an interception section, a balancing section, and a connecting section. The interception section includes anchors for anchoring the interception net in the blood vessel. The connecting section includes a plurality of biodegradable connecting wires, one end of each connecting wire being connected to the end of the interception section away from the anchor, and the other end being connected to the balancing section.

[0007] In one embodiment, the connecting wire is made of L-polylactic acid, racemic polylactic acid, polyglycolic acid, polylactic acid-glycolic acid copolymer, polyhydroxy fatty acid ester, polydioxanone, polycaprolactone, polygluconic acid, polyhydroxybutyric acid, polyanhydride, polyphosphate, polyglycolic acid, or polydioxanone.

[0008] In one embodiment, the connecting wire is made of a polymer visible under medical imaging equipment. The polymer includes a biodegradable polymer and a material visible under medical imaging equipment, wherein the biodegradable polymer and the material visible under medical imaging equipment are linked by chemical bonds.

[0009] In one embodiment, the diameter of the connecting wire is 0.5 to 5 mm.

[0010] In one embodiment, the connecting wires have different diameters, and the diameter of the end of the connecting wire connected to the balancing part is smaller than the diameter of the other parts of the connecting wire.

[0011] In one embodiment, the connecting wire includes a first segment and a second segment connected to the first segment, the second segment being connected to the balancing part, and the ratio of the wire diameter of the first segment to the second segment is (2~5):1.

[0012] In one embodiment, the connecting wire includes a biodegradable wire body and a plurality of filaments disposed on the biodegradable wire body, the plurality of filaments being radially spread out.

[0013] In one embodiment, the material of the balancing part is an absorbable material.

[0014] In one embodiment, the balancing part is a hollow tube structure, including at least one wave-shaped ring, and when there are multiple wave-shaped rings, the multiple wave-shaped rings are arranged at intervals along the axial direction.

[0015] In one embodiment, the wavy annulus is provided with an endothelial-promoting coating that at least covers the inner wall of the wavy annulus.

[0016] The aforementioned medical device is anchored via balancing sections and anchors located at both ends of the connecting portion. This ensures that the balancing and intercepting sections remain balanced on both sides of the connecting portion along its axial direction. Under the impact of blood flow or vascular torsion, the medical device is prevented from tilting, thus avoiding the difficulty in retrieval caused by tilting and adhering to the vessel wall. Furthermore, because the intercepting section is anchored in the blood vessel via the anchors, the contact area between the entire intercepting section and the vessel wall is small. Even if endothelial overgrowth occurs, the area of ​​the intercepting section covered by the endothelial cell membrane is also small. This makes it easier to retrieve the intercepting section when the connecting wire breaks due to degradation and the connection between the connecting wire and the intercepting or balancing section is severed. Attached Figure Description

[0017] Figure 1 A schematic diagram of the structure of a medical device according to one embodiment;

[0018] Figure 2 for Figure 1 A schematic diagram of the planar structure of the medical device shown;

[0019] Figure 3 This is a schematic diagram of the interception part and the connecting part of a medical device according to one embodiment;

[0020] Figure 4A schematic diagram of the structure of a medical device according to another embodiment;

[0021] Figure 5 for Figure 4 A schematic diagram of the planar structure of the medical device shown;

[0022] Figure 6 This is a schematic diagram of the connecting wire in one embodiment. Detailed Implementation

[0023] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0025] In the field of interventional medical devices, the "proximal end" is defined as the end closer to the heart, and the "distal end" is defined as the end farther from the heart. "Axial" refers to the direction parallel to the line connecting the center of the distal end and the center of the proximal end of the medical device, and "radial" refers to the direction perpendicular to the aforementioned axial direction.

[0026] Please refer to the following: Figure 1 and Figure 2 A medical device 100 according to one embodiment includes an interception section 10, a balancing section 20, and a connecting section 30. The interception section 10 is used to intercept an obstruction (e.g., a thrombus) in a blood vessel, and the balancing section 20 is used to keep the interception section 10 balanced axially to prevent the interception section 10 from tilting. The two ends of the connecting section 30 are respectively connected to the interception section 10 and the balancing section 20. Furthermore, the connection between the connecting section 30 and one of the interception section 10 and the balancing section 20 is detachable, so that after the interception section 10 has completed its intended interception function, the connection between the connecting section 30 and one of the interception section 10 and the balancing section 20 is disconnected, thereby allowing the interception section 10 to be retrieved.

[0027] Please refer to 1 and 2 together. Figure 3In one embodiment, the interception section 10 includes an interception net 1, a connector 110, and anchor spikes 120. The interception net 1 includes an inner interception net 130. The inner interception net 130 includes a plurality of first interception bars 131, one end of which converges at the connector 110, and the other end opens radially. That is, the plurality of first interception bars 131 open radially from the end connected to the connector 110 in a direction away from the longitudinal central axis III-III, thereby forming a structure with an outline shape similar to an octopus.

[0028] An anchor 120 is disposed at the end of the first interceptor 131 away from the connector 110. In one embodiment, all the first interceptors 131 are provided with anchor 120. In another embodiment, some of the first interceptors 131 are provided with anchor 120, and some of the first interceptors 131 are not provided with anchor 120. When the medical device 100 is implanted into a blood vessel, the anchor 120 penetrates into the blood vessel wall, thereby anchoring the interceptor 10 in the blood vessel.

[0029] Please see Figure 3 In one embodiment, the first intercepting rod 131 has an end face 1311 away from the connector 110. The anchor 120 is connected to the end face 1311, and the contact area between the anchor 120 and the end face 1311 is smaller than the area of ​​the end face 1311 itself, so that the portion of the end face 1311 that does not contact the anchor 120 forms an abutment portion 1311A. When the anchor 120 pierces the blood vessel wall, the abutment action of the abutment portion 1311A prevents the anchor 120 from excessively piercing the blood vessel wall and rupturing the blood vessel, thereby improving the safety of use.

[0030] In one embodiment, there are two anchors 120 on the first intercepting bar 131, and the two anchors 120 are disposed at intervals on the end face 1311. The free ends of the two anchors 120 are far apart from each other, and the end face 1311 forms an abutment portion 1311A.

[0031] It should be noted that in other embodiments, the anchor 120 can adopt other structures and arrangements, as long as the intercepting part 10 is anchored in the blood vessel through a spike-like structure with a small contact surface. For example, in one embodiment, the anchor 120 and the first intercepting rod 131 are an integral structure. The end of the first intercepting rod 131 away from the connector 110 is bent or folded, and the bent or folded end is ground and polished to form a spike structure, which is the anchor 120. Alternatively, in another embodiment, a cutting method is used to cut one end of the first intercepting rod 131 into two parts, and the spike structure formed by grinding and polishing one part is the anchor 120.

[0032] In one embodiment, a protective layer is provided on at least a portion of the surface of the first interceptor bar 131 and on the anchor bar 120 to slow endothelial cell migration. Furthermore, at least a portion of the surface of the first interceptor bar 131 with the protective coating includes the surface of the first interceptor bar 131 adjacent to the anchor bar 120. The material of the protective layer is tertiary amine-modified polyethersulfone, heparinized polyethersulfone, polytetrafluoroethylene, or polyethylene terephthalate.

[0033] Among them, tertiary amine-modified polyethersulfone refers to polyethersulfone with a tertiary amine grafted onto its molecular chain. For example, polyethersulfone undergoes a chlorosulfonation reaction, and then the tertiary amine is grafted between the chlorosulfonic acid group and the hydroxyl group. Heparinized polyethersulfone refers to polyethersulfone with a heparin molecule grafted onto its molecular chain. For example, heparin molecules are grafted onto the diamine spatial arm.

[0034] Please continue reading. Figure 3 In one embodiment, the intercepting net 1 further includes an outer intercepting net 140, which includes a plurality of second intercepting rods 141. One end of each second intercepting rod 141 converges at the connector 110, and the other end opens radially, i.e., the plurality of second intercepting rods 141 open radially from the end connected to the connector 110 in a direction away from the longitudinal central axis III-III, thereby forming a structure with an octopus-like outline. The axial length of the second intercepting rods 141 is shorter than the axial length of the first intercepting rod 131. Furthermore, the plurality of second intercepting rods 141 are all located outside the first intercepting rod 131. Here, "outer side" refers to the side away from the longitudinal central axis III-III, and "inner side" refers to the side closer to the longitudinal central axis III-III. That is, when the medical device 100 is implanted into a blood vessel, the radially opposite portion of the first intercepting rod 131 to the second intercepting rod 141 is further away from the blood vessel wall than the corresponding second intercepting rod 141.

[0035] It is understood that in other embodiments, the outer intercepting net 140 can be omitted, and only the inner intercepting net 130 can effectively intercept blockages in blood vessels. Furthermore, by only providing the inner intercepting net 130, the radial dimension of the radially compressed intercepting part 10 is smaller, making it easier to deliver and release.

[0036] However, by simultaneously setting up an inner intercepting net 130 and an outer intercepting net 140 to form a dual intercepting net structure, selective interception of obstructions of different sizes can be achieved. This helps to prevent excessive obstructions from adhering to the inner intercepting net 130 and the outer intercepting net 140 and thus blocking blood flow before thrombolysis or aspiration measures are taken.

[0037] The diameters of the first interceptor bar 131 and the second interceptor bar 141 can be equal or unequal, and the number of the first interceptor bar 131 and the second interceptor bar 141 can also be equal or unequal. By reasonably setting the diameter and number of the first interceptor bar 131 and the second interceptor bar 141, selective interception can be achieved.

[0038] In one embodiment, the first interceptor bar 131 and the second interceptor bar 141 have the same diameter, and the number of first interceptor bars 131 is greater than the number of second interceptor bars 141, so that the inner interceptor net 130 can intercept smaller obstructions, and the outer interceptor net 140 can intercept larger obstructions. In a more specific embodiment, the first interceptor bar 131 and the second interceptor bar 141 have the same diameter, ranging from 0.2 to 3 mm, and the number of first interceptor bars 131 is greater than the number of second interceptor bars 141, with the number of first interceptor bars 131 ranging from 4 to 7 and the number of second interceptor bars 141 ranging from 3 to 5, to balance selective interception and transport performance.

[0039] In another embodiment, the number of first interceptor bars 131 and second interceptor bars 141 is equal, but the diameter of the first interceptor bar 131 is larger than that of the second interceptor bar 141, so that the inner interceptor net 130 can intercept smaller obstructions, and the outer interceptor net 140 can intercept larger obstructions. In a more specific embodiment, the number of first interceptor bars 131 and second interceptor bars 141 is equal, and the number ranges from 3 to 8. The diameter of the first interceptor bar 131 is larger than that of the second interceptor bar 141, and the diameter of the first interceptor bar 131 ranges from 1 to 2 mm, while the diameter of the second interceptor bar 141 ranges from 0.2 to 1 mm, to balance selective interception and transport performance.

[0040] It is understood that in other embodiments, the number and diameter of the first intercepting rod 131 and the second intercepting rod 141 can be different. By reasonably setting the diameter and number of the two rods, the inner intercepting net 130 and the outer intercepting net 140 can also have selective interception functions.

[0041] Whether the interceptor 10 includes only the inner interceptor mesh 130 or both the inner interceptor mesh 130 and the outer interceptor mesh 140, the interceptor 10 can be integrally formed by cutting a tube. For example, the interceptor 10 can be formed by cutting a shape memory material tube.

[0042] It is also understood that the shape of the first interceptor bar 131 and the second interceptor bar 141 is not limited, and can be a round bar, a rectangular bar, a square bar, or other regular or irregular shape bars.

[0043] Please return Figure 2The balancing section 20 is a hollow tubular structure, including at least one corrugated annular element 210. In one embodiment, the number of corrugated annular elements 210 is one. In another embodiment, there are at least two corrugated annular elements 210, which are arranged at axial intervals. Any two adjacent corrugated annular elements 210 are connected by a connector (not shown). The structure of the connector is not limited; any connector capable of axially connecting the corrugated annular elements 210 without affecting the conveying and anchoring performance is suitable.

[0044] Each waveform ring 210 has a peak-valley structure, including a wave rod and an arc-shaped connector for connecting the wave rod. The radial force of the waveform ring 210 stably anchors the balance part 20 in the blood vessel, thereby reliably anchoring the medical device 100 in the blood vessel.

[0045] It should be noted that the axial length of each waveform ring 210 should not be too long, and the number of waveform rings 210 should not be too many. Under the premise of being able to achieve anchoring and maintain balance with the interception part 10 in the axial direction, the axial length of the balancing part 20 should be as short as possible, so that the medical device 100 has better flexibility and is conducive to convenient delivery through curved blood vessels.

[0046] In one embodiment, when the number of wave-shaped rings 210 is 1, the axial length of the wave-shaped rings 210 is 0.8 to 3.5 cm.

[0047] In another embodiment, the number of wave-shaped rings 210 is 2 to 4, and the axial length of each wave-shaped ring 210 is 0.5 to 1.8 cm.

[0048] In one embodiment, the wave-shaped ring 210 includes 8 to 16 wave rods, and the number of wave-shaped rings 210 is 2 to 6, with each wave-shaped ring 210 having an axial length of 0.5 to 1 cm. This arrangement avoids excessive axial length of the balancing part 20 and ensures that each wave-shaped ring 210 has sufficient radial support performance.

[0049] In one embodiment, the material of the wave-shaped ring 210 is a shape memory material, which gives the balancing part 20 self-expanding properties. When the compressed medical device 100 is delivered into the blood vessel through the delivery sheath, the balancing part 20 expands and abuts against the blood vessel wall to achieve anchoring.

[0050] In one embodiment, the material of the wavy annular structure 210 is an absorbable material so that the balancing section 20 can gradually degrade after the interception section 10 has completed its intended interception function and been recovered from the blood vessel. The absorbable material can be a corrosive metal or a biodegradable polymer.

[0051] In one embodiment, the absorbable material is pure iron, an iron-based alloy, pure magnesium, or a magnesium-based alloy. In another embodiment, the absorbable material is polylactic acid, polyglycolic acid, polycaprolactone, or a polylactic-glycolic acid copolymer.

[0052] In one embodiment, the wavy ring 210 is provided with an endothelial-promoting coating that at least covers the inner wall of the wavy ring 210, so that after implantation, regardless of whether the wavy ring 210 is made of absorbable or non-absorbable material, the wavy ring 210 can be quickly covered by the endothelial cell membrane, thus avoiding thrombosis.

[0053] In one embodiment, the material for promoting the endothelial coating is selected from at least one of tyrosine-isoleucine-glycine-serine-arginine pentapeptide, cyclic (arginine-glycine-aspartic acid-tyrosine-lysine), and polypeptides containing the arginine-glycine-aspartic acid sequence.

[0054] In one embodiment, the thickness of the endothelial coating is 20 to 80 micrometers.

[0055] Please refer to the following: Figure 2 and Figure 3 The connecting part 30 includes multiple connecting rods 310. One end of each connecting rod 310 is connected to the intercepting part 10, and the other end is connected to the balancing part 20. Furthermore, the connection between the connecting rod 310 and one of the intercepting part 10 and the balancing part 20 is detachable. Specifically, one end of each connecting rod 310 is connected to the end of the intercepting part 10 furthest from the anchor 120, and the other end is connected to the balancing part 20, meaning the connecting rod 310 is located between the anchor 120 and the balancing part 20. The anchor 120 is used to anchor the intercepting part 10. The connecting action of the connecting rods 310 lifts the end of the intercepting part 10 furthest from the anchor 120, preventing the end of the intercepting part 10 furthest from the anchor 120 from tilting and adhering to the wall due to lack of support and the impact of blood flow. This allows the medical device 100 to maintain its implanted shape for a longer period, thus better achieving the function of intercepting vascular obstructions.

[0056] In one implementation, such as Figure 2 As shown, one end of each connecting rod 310 is connected to the connector 110, and the other end extends into the balance part 20 and is connected to the end of the balance part 20 away from the intercepting part 10.

[0057] In one implementation, such as Figure 2As shown, one end of each connecting rod 310 is connected to the connector 110, and the other end extends into the balancing part 20 and is connected to the end of the balancing part 20 away from the intercepting part 10. Furthermore, the connection between the connecting rod 310 and the connector 110 is detachable. When the connection between the connecting rod 310 and the connector 110 is broken, the end of the connecting rod 310 connected to the connector 110 moves towards the inner wall of the balancing part 20 until the connecting rod 310 is parallel or approximately parallel to the longitudinal central axis of the balancing part 20.

[0058] When the connection between the connecting rod 310 and the connector 110 is broken, the end of the connecting rod 310 connected to the connector 110 can move towards the inner wall of the balancing part 20 until the connecting rod 310 and the longitudinal central axis of the balancing part 20 are parallel. This can be achieved in various ways. For example, both the connecting rod 310 and the balancing part 20 are made of shape memory material, and the connecting rod 310 and the balancing part 20 are a single-piece structure (e.g., a single-piece structure formed by cutting a tube, a single-piece structure formed by 3D printing, or a single-piece structure formed by weaving shape memory alloy wire). Before one end of the connecting rod 310 is connected to the connector 110, in its natural state, the connecting rod 310 is parallel to the longitudinal central axis of the balancing part 20. When the connection between the connecting rod 310 and the connector 110 is broken, the connecting rod 310 returns to its natural shape and is parallel or approximately parallel to the longitudinal central axis of the balancing part 20.

[0059] For example, the connecting rod 310 is an elastic rod, and the connecting rod 310 and the balancing part 20 are not an integral structure. One end of the connecting rod 310 is fixedly connected to the end of the balancing part 20 away from the anchor 120 (e.g., by welding, snap-fit ​​connection, etc.). When the other end of the connecting rod 310 is not yet connected to the intercepting part 10, the connecting rod 310 is parallel to the longitudinal central axis of the balancing part 20. When the other end of the connecting rod 310 is connected to the intercepting part 10, the connecting rod 310 deforms. When the connection between the connecting rod 310 and the intercepting part 10 is broken, the connecting rod 310 returns to its original position and becomes parallel to the longitudinal central axis of the balancing part 20.

[0060] In this context, "approximately parallel" means that when the connection between the connecting rod 310 and the joint 110 is broken, the connecting rod 310 tends to align with the inner wall of the balancing part 20, but it may not be 100% parallel to the longitudinal central axis of the balancing part 20. Instead, it may deviate slightly. For example, if the angle between the connecting rod 310 and the longitudinal axis of the balancing part 20 after the connection with the joint 110 is broken is greater than 0° and less than 10°, it can be considered approximately parallel.

[0061] Please refer to the following: Figure 4 and Figure 5In one embodiment, one end of each connecting rod 310 is connected to the connector 110, and the other end is connected to the end of the balancing part 20 near the intercepting part 10. Furthermore, the connection between the connecting rod 310 and the balancing part 20 is detachable.

[0062] In another embodiment, when the connection between the connecting rod 310 and the balancing part 20 is detachable, the connecting rod 310 can be connected to either the end of the balancing part 20 closest to the intercepting part 10 or the end of the balancing part 20 furthest from the intercepting part 10. When the connection between the connecting rod 310 and the balancing part 20 is broken, since the connecting rod 310 remains connected to the intercepting part 10, it retracts along with the retraction of the intercepting part 10. For example, in one embodiment, such as Figure 2 As shown, one end of each connecting rod 310 is connected to the connector 110, and the other end extends into the balancing part 20 and is connected to the end of the balancing part 20 away from the intercepting part 10. Furthermore, the connection between the connecting rod 310 and the balancing part 20 is detachable. When the connection between the connecting rod 310 and the balancing part 20 is broken, the connecting rod 310 and the intercepting part 10 are retracted together.

[0063] When the connection between the connecting rod 310 and the balance part 20 is detachable, in one embodiment, the diameter of the connecting rod 310 is 0.1 to 2.5 mm. Properly setting the diameter of the connecting rod 310 avoids both situations where the connecting rod 310 is too thick, requiring a larger sheath for transport and retrieval, and where the connecting rod 310 is too thin, increasing manufacturing difficulty.

[0064] Regardless of the connection method between the connecting rod 310 and the interception section 10 and the balancing section 20, when the connecting rod 310 is simultaneously connected to both the interception section 10 and the balancing section 20, the multiple connecting rods 310 form an additional interception net, enabling the connecting section 30 to simultaneously perform both connecting and intercepting vascular obstructions. By rationally setting the number and diameter of the multiple connecting rods 310, and cooperating with the inner interception net 130 and the outer interception net 140, a three-level progressive interception is achieved, improving the selectivity for obstructions and further helping to avoid blocking blood flow.

[0065] When the interception section 10 is located at the proximal end and the balance section 20 is located at the distal end, the blood flow flows from the distal end to the proximal end. Therefore, the blood flow first passes through the additional interception net. In order to achieve the effect of selective interception, the additional interception net should be able to intercept larger obstructions while allowing smaller obstructions to pass through.

[0066] In one embodiment, the number of connecting rods 310 ranges from 3 to 5, and the rod diameter ranges from 0.5 to 2 mm.

[0067] In one embodiment, the diameters of the first intercepting rod 131 and the second intercepting rod 141 are equal and range from 0.2 to 3 mm. The number of the first intercepting rods 131 is greater than the number of the second intercepting rods 141, and the number of the first intercepting rods 131 ranges from 4 to 7, while the number of the second intercepting rods 141 ranges from 3 to 5, in order to balance selective interception and transport performance. The number of connecting rods 310 is 3 to 5, and the diameter of each connecting rod 310 is smaller than the diameters of the first intercepting rods 131 and the second intercepting rods 141, so that the additional intercepting net can intercept the largest size of the obstruction, the outer intercepting net 140 can intercept the larger size of the obstruction, and the inner intercepting net can intercept the smallest size of the obstruction.

[0068] In another embodiment, the number of first interceptor bars 131 and second interceptor bars 141 is equal, ranging from 3 to 8. The diameter of the first interceptor bar 131 is larger than that of the second interceptor bar 141, and the diameter of the first interceptor bar 131 ranges from 1 to 2 mm, while the diameter of the second interceptor bar 141 ranges from 0.5 to 1 mm. The number of connecting bars 310 is 3 to 4, and the diameter of the connecting bars 310 ranges from 0.1 to 0.2 mm. This arrangement enables the outer interceptor bar 140 to intercept the largest size obstruction, the outer interceptor bar 140 to intercept larger size obstructions, and the inner interceptor bar 130 to intercept the smallest size obstruction.

[0069] It should be noted that when the additional intercepting net is located at the proximal end and the intercepting part 10 is located at the distal end, the order of selective interception is reversed, that is, the inner intercepting net 130 intercepts the largest size obstruction, the outer intercepting net 140 intercepts the larger size obstruction, and the additional intercepting net intercepts the smallest size obstruction.

[0070] It should also be noted that the disconnectable connection can be any disconnectable connection method known to those skilled in the art. In one embodiment, the connecting rod 310 is connected to the intercepting part 10 or the balancing part 20 via a biodegradable line (not shown). When the biodegradable line breaks due to degradation, the connection between the connecting rod 310 and the intercepting part 10 or the balancing part 20 is disconnected.

[0071] In one embodiment, one end of the connector 110 has a through hole, and a biodegradable thread is wound around the through hole and connected to the connecting rod 310. A weak point is provided on the biodegradable thread, but this weak point is not located at the through hole. This allows the biodegradable thread to break preferentially at this weak point, thus disconnecting the connection between the connecting rod 310 and the intercepting part 10. Furthermore, the broken biodegradable thread remains wound around the connector 110, preventing the formation of broken fragments. Alternatively, the biodegradable thread is wound around a corrugated ring 210, and a weak point is provided on the biodegradable thread, located outside the corrugated ring 210. This allows the biodegradable thread to break preferentially at this weak point, thus disconnecting the connection between the connecting rod 310 and the balancing part 20. Furthermore, the broken biodegradable thread remains wound around the corrugated ring 210, preventing the formation of broken fragments.

[0072] It should be noted that the connecting rod 310 can be a rod-shaped object made of metal. For example, the connecting rod 310 is a nickel-titanium alloy rod.

[0073] In one embodiment, the connecting rod 310 is omitted, and the connecting portion 30 includes a plurality of connecting wires. The connecting wires are flexible filaments, and the material of the connecting wires is absorbable. It is understood that the connection method between the connecting wires and the intercepting portion 10 and the balancing portion 20 is the same as the connection method between the connecting rod 310 and the intercepting portion 10 and the balancing portion 20, and will not be repeated here. The only difference between the connecting wires and the connecting rod 310 is the material and rigidity. The connecting wires are biodegradable polymer fibers. In one embodiment, the biodegradable polymer is L-polylactic acid, racemic polylactic acid, polyglycolic acid, polylactic-co-hydroxyacetic acid copolymer, polyhydroxyalkanoate, polydioxanone, polycaprolactone, polygluconic acid, polyhydroxybutyric acid, polyanhydride, polyphosphate, polyglycolic acid, or polydioxanone.

[0074] In one embodiment, the connecting wire is made of a polymer visible under medical imaging equipment. The polymer includes a biodegradable polymer and a material visible under medical imaging equipment, the biodegradable polymer and the material visible under medical imaging equipment being linked by chemical bonds. In one embodiment, the material visible under medical imaging equipment is an iodine-containing material.

[0075] The use of a polymer that is visible under medical imaging equipment allows the connecting wires to be visualized under medical imaging equipment (e.g., DSA). Because the connecting wires are visible under medical imaging equipment, it is possible to confirm whether the connecting wires are broken before recycling the medical device 100.

[0076] In one embodiment, the polymer visible under medical imaging equipment is selected from at least one of polylactic acid iodide (I-PLA), polycarbonate iodide (I-PC), cellulose iodide, polymethyl methacrylate iodide (I-PMMA), polyurethane iodide (I-PU), and polycaprolactone iodide (I-PCL). A portion of the groups on the molecular chains of polylactic acid, polycarbonate, cellulose, polymethyl methacrylate, polyurethane, and polycaprolactone are acquired by I to obtain the aforementioned polymer visible under medical imaging equipment.

[0077] The material and diameter of the connecting wire can be appropriately set so that the breakage of the connecting wire matches the recycling window of the medical device 100. For example, if it is desired to recycle the medical device 100 in about one month, the connecting wire will break within about one month.

[0078] In one embodiment, the molecular weight of the biodegradable polymer ranges from 1,000 Da to 400,000 Da, and the polydispersity index of the biodegradable polymer ranges from 1.1 to 5.

[0079] In one embodiment, the diameter of the connecting wire is 0.5 to 5 mm.

[0080] In one embodiment, the connecting wires have different diameters, and the diameter of the end of the connecting wire connected to the balance part 20 is smaller than the diameter of the other parts of the connecting wire, so that the connecting wire breaks from the end connected to the balance part 20. When the intercepting part 10 is recycled, the remaining connecting wire and the intercepting part 10 are recycled together.

[0081] In one embodiment, the connecting wire 320 includes a first segment and a second segment axially connected to the first segment. Both the first and second segments are of equal diameter, with the diameter of the first segment being larger than that of the second segment. The second segment is connected to the balancing part 20, allowing it to break preferentially. In one embodiment, the ratio of the diameters of the first and second segments is (2~5):1, and the ratio of the lengths of the first and second segments is (2~4):1, to ensure that the second segment breaks preferentially and to maintain the overall connection strength of the connecting wire 320, preventing premature breakage of the connecting wire 320.

[0082] In another embodiment, the first segment is a wire of constant diameter and the second segment is a wire of variable diameter. The wire diameter of the second segment gradually decreases from the end where it is connected to the first segment and the balance part 20, so that the part where the second segment is connected to the balance part 20 breaks first.

[0083] In one embodiment, the cross-section of the connecting wire 320 is circular or elliptical, and the wire diameter of the connecting wire 320 gradually decreases from the end connected to the intercepting part 10 to the end connected to the balancing part 20. In this way, the end of the connecting wire 320 connected to the balancing part 20 can be broken first.

[0084] The connecting wire has a weak point, causing it to break preferentially at the weak point, thus severing its connection with the intercepting part 10 or the balancing part 20. In one embodiment, the weak point may be a portion of the connecting wire with a degradation-promoting coating, or it may be a portion of the connecting wire not covered by a protective layer. For example, the portion of the connecting wire that connects to the intercepting part 10 or the balancing part 20 may have a degradation-promoting coating.

[0085] In one embodiment, when the balancing part 20 is located at the proximal end and the intercepting part 10 is located at the distal end, such as Figure 6 As shown, the connecting wire includes a biodegradable wire body 321 and multiple threads 322 disposed on the biodegradable wire body 321. The multiple threads 322 are radially spread out. The material of the threads 322 can be the same as or different from the material of the biodegradable wire body 321. This structure of the connecting wire is beneficial for adsorbing thrombi, so that without increasing the wire diameter of the biodegradable wire body 321 or increasing the number of connecting wires, the additional interception network formed by the multiple connecting wires can further adsorb smaller vascular obstructions, thereby preventing embolism.

[0086] The intercepting part 10 and the balancing part 20 of the aforementioned medical device 100 are balanced axially, which helps to prevent the intercepting part 10 from tilting and sticking to the wall. Furthermore, the intercepting part 10 is anchored to the blood vessel wall by the anchor 120. This anchoring method minimizes the contact area between the intercepting part 10 and the blood vessel wall, preventing the intercepting part 10 from being extensively covered by the endothelial cell membrane, thus facilitating retrieval.

[0087] Meanwhile, because the medical device 100 can maintain balance in the blood vessels and can avoid the interception part 10 being covered by the endothelial cell membrane over a large area, its recovery window is relatively long.

[0088] Furthermore, the interception section 10 and the balancing section 20 are connected by the connecting part 30. By reasonably setting the structure of the connecting part 30 and the connection method between the connecting part 30 and the interception section 10 and the balancing section 20, the connecting part 30 forms an additional interception net, which improves the filtration selectivity of the medical device 100, avoids obstruction of blood flow, and improves the safety of use.

[0089] Please return Figure 4The medical device 100 also includes a retrieval section 40. The retrieval section 40 is connected to the end of the connector 110 furthest from the anchor 120. The retrieval section 40 is used in conjunction with a grasping device to retrieve the interceptor section 10. In this embodiment, the retrieval section 40 is a hook-shaped member with a curved hook portion 410. During retrieval, the grasping device grabs the curved hook portion 410 to retrieve the interceptor section 10. It is understood that in other embodiments, the retrieval section 40 may have other structures. For example, the retrieval section 40 may include a support member and a plurality of retrieval hooks spaced circumferentially along the support member, and the support member is connected to the connector 110. When retrieving the interceptor section 10, the retrieval of the interceptor section 10 can be conveniently achieved by using the grasping device to grab any one of the retrieval hooks.

[0090] The following specific examples further illustrate this point.

[0091] Example 1

[0092] A medical device includes an interception section, a balancing section, and a connecting section. The interception section includes an inner interception mesh and an outer interception mesh. The balancing section includes three axially connected corrugated rings. The connecting section includes three polylactic acid (PLA) filaments. One end of each PLA filament is connected to a connector in the interception section, and the other end is connected to the end of the balancing section closest to the interception section. Furthermore, each PLA filament has a circular cross-section, and the diameter of the filament gradually decreases from the end connected to the interception section to the end connected to the balancing section, with a diameter of 2 mm at the end connected to the interception section and 0.5 mm at the end connected to the balancing section.

[0093] A tertiary amine-modified polyethersulfone coating is formed on the first interceptor bar of the interceptor section by spraying. The thickness of the tertiary amine-modified polyethersulfone coating is 20 micrometers.

[0094] The medical device was implanted into the inferior vena cava of a sheep and retrieved after 3 months. The retrieval process was successful, indicating that the area of ​​the medical device covered by the endothelial cell membrane was small and that the connecting wire had already broken at the time of retrieval.

[0095] Example 2

[0096] A medical device includes an interception section, a balancing section, and a connecting section. The interception section includes an inner interception mesh and an outer interception mesh. The balancing section includes two axially connected corrugated rings. The connecting section includes three polylactic acid iodide filaments. One end of each polylactic acid iodide filament is connected to a connector of the interception section, and the other end is connected to the end of the balancing section closest to the interception section. Each polylactic acid iodide filament includes a first segment of equal diameter and a second segment of equal diameter. The first segment and the second segment are axially connected. The end of the first segment furthest from the second segment is connected to the interception section, and the end of the second segment furthest from the first segment is connected to the balancing section. The diameter of the first segment is 1 mm, and the diameter of the second segment is 0.5 mm.

[0097] A tertiary amine-modified polyethersulfone coating is formed on the first interceptor bar of the interceptor section by spraying. The thickness of the tertiary amine-modified polyethersulfone coating is 20 micrometers.

[0098] The medical device was implanted into the inferior vena cava of pigs. Two months later, a follow-up revealed that the connecting wire had broken. Retrieval was successful, indicating that the area of ​​the medical device covered by the endothelial cell membrane was relatively small.

[0099] Example 3

[0100] A medical device includes an interception section, a balancing section, and a connecting section. The interception section includes an inner interception mesh and an outer interception mesh. The balancing section includes three axially connected corrugated rings made of pure iron, and all surfaces of the corrugated rings are coated with a tyrosine-isoleucine-glycine-serine-arginine pentapeptide coating. The connecting section includes three iodinated poly(ε-caprolactone) filaments. One end of each iodinated poly(ε-caprolactone) filament is connected to a connector in the interception section, and the other end is connected to the end of the balancing section closest to the interception section. Each iodinated poly(ε-caprolactone) filament includes a first segment and a second segment of equal diameter, which are axially connected. The end of the first segment furthest from the second segment is connected to the interception section, and the end of the second segment furthest from the first segment is connected to the balancing section. The diameter of the first segment is 5 mm, and the diameter of the second segment is 12 mm.

[0101] A heparinized polyethersulfone coating is formed on the first interceptor bar of the interceptor section by spraying. The thickness of the heparinized polyethersulfone coating is 50 micrometers.

[0102] The medical device was implanted into the inferior vena cava of pigs. A follow-up three months later revealed that the connecting wire had broken. Retrieval was successful, indicating that the area of ​​the medical device covered by the endothelial cell membrane was relatively small.

[0103] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0104] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A medical device for intercepting blockages in blood vessels, characterized in that, The device includes an interception section, a balancing section, and a connecting section. The interception section includes an interception net and anchors for anchoring the interception net in a blood vessel. The balancing section is used to keep the interception section balanced in the axial direction. The connecting section includes a plurality of biodegradable connecting wires, one end of each connecting wire being connected to the end of the interception section away from the anchor, and the other end being connected to the balancing section. The diameters of the connecting wires are not equal, and the diameter of the end of the connecting wire connected to the balance part is smaller than the diameter of the other parts of the connecting wire. The balancing part is a hollow tube structure, including at least one wave-shaped ring, and when there are multiple wave-shaped rings, the multiple wave-shaped rings are arranged at intervals along the axial direction.

2. The medical device according to claim 1, characterized in that, The connecting wire is made of L-polylactic acid, racemic polylactic acid, polyglycolic acid, polylactic acid-glycolic acid copolymer, polyhydroxy fatty acid ester, polydioxanone, polycaprolactone, polygluconic acid, polyhydroxybutyric acid, polyanhydride, polyphosphate ester, polyglycolic acid, or polydioxanone.

3. The medical device according to claim 1, characterized in that, The connecting wire is made of a polymer visible under medical imaging equipment. The polymer includes a biodegradable polymer and a material visible under medical imaging equipment, and the biodegradable polymer and the material visible under medical imaging equipment are linked by chemical bonds.

4. The medical device according to claim 1, characterized in that, The diameter of the connecting wire is 0.5 to 5 mm.

5. The medical device according to claim 1, characterized in that, The connecting wire includes a first segment and a second segment connected to the first segment. The second segment is connected to the balancing part. The ratio of the wire diameter of the first segment to the second segment is (2-5):

1.

6. The medical device according to claim 1, characterized in that, The connecting wire includes a biodegradable wire body and multiple filaments disposed on the biodegradable wire body, the multiple filaments being radially spread out.

7. The medical device according to claim 1, characterized in that, The material of the balancing part is an absorbable material.

8. The medical device according to claim 1, characterized in that, The wavy annular structure is provided with an endothelial-promoting coating that at least covers the inner wall of the wavy annular structure.

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