Distal embolic protection device

Abstract

The present invention discloses a distal embolic protection device, comprising a protective umbrella and an intracavitary rib coaxially disposed on a delivery guidewire. The protective umbrella's support frame is a hollow structure with two first openings at its proximal end, the two first openings being symmetrically arranged along the central axis of the support frame. A membrane is fixed to the distal end of the support frame and partially wraps around it. The membrane is provided with a plurality of holes. The intracavitary rib is located within the support frame and is a hollow structure, with a second opening facing the distal end of the support frame. The present invention utilizes the intracavitary rib and the membrane to form a double-layer filtering structure, thereby effectively improving the accumulation of thrombus clots within the protective umbrella's lumen, reducing the probability of clogging of the protective umbrella's mesh / micropores, and ensuring adequate blood supply to the nervous system. The coaxial arrangement of the intracavitary rib and the support frame improves the stability of the protective umbrella within the blood vessel, making it less likely to tilt and ensuring effective capture of free thrombi. The provision of the two first openings ensures that an effective capture channel is provided even under tilted conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a coaxial distal embolism protection device. Background Art

[0002] During peripheral artery and coronary artery interventions, the use of implantable devices such as guidewires, catheters, balloons, and stents can lead to the formation of free thrombi. These clots can be transported by the bloodstream to the nervous system, causing vascular obstruction and potentially fatal harm to the patient. Therefore, embolic protection devices (distal umbrellas) are commonly used clinically, placed at the distal end of the bloodstream at the lesion site to capture free thrombi and prevent embolism in the nervous system.

[0003] In the prior art, embolic protection devices can be classified into two types, eccentric and coaxial, based on the relative positional relationship between the proximal opening and the delivery guidewire. In eccentric embolic protection devices, the guidewire and the protective umbrella are not coaxial, the proximal opening has no obstructing structure, and the capture efficiency of free thrombus clots is high. However, the disadvantage is poor centrality, which can easily lead to deflection due to uneven force during operation. In this case, whether the proximal opening is a circular opening parallel to the cross-section of the blood vessel or an elliptical opening at a certain angle to the cross-section of the blood vessel, the proximal opening will be blocked and some of the capture function will be lost. In extreme cases, the proximal opening of the protective umbrella will completely adhere to the blood vessel wall, causing the protective umbrella to completely lose its function. The coaxial embolic protection device overcomes the disadvantage of the eccentric type that is prone to tilting, but because of the need to maintain the coaxial effect, several connecting rods need to be added between the delivery guidewire and the protection device. The interference of the connecting rods reduces the capture efficiency of free thrombus.

[0004] Existing embolic protection devices can be categorized by structure into woven mesh and membrane-coated types. Woven mesh devices utilize dense meshes to intercept thrombi larger than the mesh diameter, while allowing blood cells smaller than the mesh diameter to pass through, providing blood supply to the nervous system. Similarly, membrane-coated devices incorporate micropores in a thin film to intercept thrombi larger than the mesh diameter, while allowing blood cells smaller than the mesh diameter to pass through, providing blood supply to the nervous system. However, if a large number of thrombi or large clots accumulate within the lumen of the device, they can clog the mesh / micropores, leading to insufficient blood supply to the nervous system and potentially harming the patient.

[0005] Therefore, it is necessary to provide a coaxial distal embolic protection device that can improve capture efficiency and reduce mesh / micropore clogging to solve the above problems. Summary of the Invention

[0006] The object of the present invention is to provide a coaxial distal embolic protection device that can improve capture efficiency and reduce mesh / micropore clogging.

[0007] To achieve the above-mentioned object, the technical solution of the present invention is as follows: a distal embolic protection device is provided, which includes a delivery guidewire, a protective umbrella and an intracavitary umbrella rib; wherein the protective umbrella includes a support bracket and a covering, the support bracket is hollow and has two first openings at its proximal end, the two first openings are symmetrically arranged along the central axis of the support bracket, the support bracket is coaxially passed through the delivery guidewire, and the support bracket has a compressed state and an expanded state, the covering is fixed to the distal end of the support bracket and adheres to the outside of the support bracket, the covering wraps a portion of the support bracket, the covering can be contracted and expanded with the support bracket, and a plurality of holes are opened on the covering; the intracavitary umbrella rib is hollow and has a second opening, the intracavitary umbrella rib is coaxially fixed to the delivery guidewire and is located in the support bracket, the second opening faces the distal end of the support bracket, and the intracavitary umbrella rib can be folded and expanded with the support bracket.

[0008] Preferably, the first opening is spindle-shaped or wedge-shaped, the length direction of each first opening is the same as the axial direction of the central axis of the support bracket, and the surface where each first opening is located forms an angle with the cross-section of the blood vessel. With this structural arrangement, even if the support bracket is tilted and the first opening on one side is blocked by the blood vessel wall, the first opening on the other side can still provide an effective capture channel equivalent to the entire blood vessel cross-sectional area, thereby improving the capture efficiency.

[0009] Preferably, the support bracket has a shuttle-shaped structure, which effectively increases the wall-adhering area, enhances the wall-adhering performance, and is not easy to tilt during use; in addition, the release and recovery of the protective umbrella are achieved by transmitting force through the delivery guide wire. The shuttle-shaped support bracket can keep the delivery guide wire in the center of the bracket segment, which is more conducive to the operation of the device.

[0010] Preferably, the support stent comprises a coaxially arranged cylindrical section and tapered sections at either end of the cylindrical section, with the first opening formed in one of the tapered sections. The cylindrical section increases the surface area for adherence to the wall, enhancing its adherence performance and making the support stent less susceptible to tilt. Furthermore, the coaxial connection of the support stent further enhances its stability within the blood vessel, effectively preventing the first opening from adhering to the vessel wall.

[0011] Preferably, the stent comprises a coaxially arranged proximal retaining ring and distal retaining ring, and a plurality of first branches connected therebetween. The plurality of first branches are staggered to form a mesh-like hollow structure. The proximal retaining ring and the distal retaining ring are respectively sleeved over the delivery guidewire. The coaxial connection between the stent and the delivery guidewire further enhances the stability of the stent within the blood vessel, making it less susceptible to tilting.

[0012] Preferably, the first branch rod includes a proximal connecting rod, a distal connecting rod and a middle connecting rod, a plurality of the middle connecting rods are staggered and connected to form a cylindrical segment with a hollow structure, at least two of the proximal connecting rods are connected to the middle connecting rod and the proximal limiting ring to form the first opening, and a plurality of the distal connecting rods are connected to the middle connecting rod and the distal limiting ring at intervals along the circumferential direction.

[0013] Preferably, the protective umbrella further comprises a head-end developing collar coaxially sleeved over the distal retaining ring, thereby pressing the coating tightly between the head-end developing collar and the distal retaining ring. The head-end developing collar effectively secures the coating to the support bracket and also facilitates positioning of the protective umbrella within the body.

[0014] Preferably, the distal limiting ring includes a first tube segment and a second tube segment in a stepped shape, and the head end developing ring is coaxially sleeved outside the first tube segment and abuts against the end face of the second tube segment, thereby stably fixing the film to the distal end of the support bracket.

[0015] Preferably, the head end developing ring is made of a radiopaque metal material.

[0016] Preferably, the head end developing sleeve is made of gold, platinum, tungsten or an alloy of at least two of the foregoing.

[0017] Preferably, the protective umbrella also includes two bracket developing springs, the two bracket developing springs are fixed on the supporting bracket and symmetrically arranged along the central axis of the supporting bracket, and the line connecting the head end developing ring and the two bracket developing springs forms an isosceles triangle, thereby forming an isosceles triangle developing effect. The operator can easily judge the deployment status of the protective umbrella, whether it is tilted, the release position, etc. according to the direction of the blood vessels and the relative positions of the three points, and can make timely adjustments.

[0018] Preferably, the support bracket is provided with an assembly branch rod, the bracket developing spring is fixed to the assembly branch rod and exposed outside the coating, and the bracket developing spring can be observed under X-rays, thereby intuitively observing the deployment status and corresponding position of the protective umbrella, thereby providing guidance for subsequent operations.

[0019] Preferably, the diameter of the holes in the covering gradually increases from the distal end to the proximal end along the central axis of the stent, and within a cross section perpendicular to the central axis of the stent, the holes have the same diameter. Because thrombi tend to accumulate near the central axis of the cone of the protective umbrella, this arrangement of holes can filter out small free thrombi while ensuring sufficient blood flow, thereby providing adequate blood supply to the nervous system.

[0020] Preferably, the covering includes a distal ring and an umbrella cap fixed to the distal ring, the distal ring is fixed to the distal end of the support bracket, and the umbrella cap is attached to the outside of the support bracket to form a protective umbrella.

[0021] Preferably, the umbrella cover includes a cone portion and a cylindrical portion, the tip of the cone portion is fixed to the distal ring, and the hole is at least opened in the cone portion, so that it can filter out smaller free thrombi and ensure sufficient blood flow to fully supply blood to the nervous system.

[0022] Preferably, the covering film is attached to the outside of the supporting bracket by heat shrinking, bonding or sewing with PP sutures.

[0023] Preferably, the covering film is a plastic film, and the holes are formed on the covering film by laser processing.

[0024] Preferably, the intracavitary ribs include a rib retaining ring and a plurality of second rods, each of which is fixed to the rib retaining ring at intervals along the circumference thereof. The end of each second rod, which is away from the rib retaining ring, forms the second opening. The rib retaining ring is coaxially fixed to the delivery guidewire. The intracavitary ribs and the peritoneum form a double-layer filtering structure. First, the intracavitary ribs are used to filter larger free thrombi, thereby preventing free thrombi from accumulating in the cone of the protective umbrella. Then, the covering membrane is used to capture smaller free thrombi, ensuring blood flow to the nervous system during surgery. Compared to the single-layer filtering structure in the prior art, the double-layer filtering structure of the present application solves the problem of free thrombi accumulating in the umbrella cavity, thereby effectively preventing clogging of the mesh or micropores. In addition, the intracavitary ribs increase the support of the protective umbrella, making it less likely to tilt or fail to fully unfold.

[0025] Preferably, each of the second rods and the rib limiting ring is integrally formed or is formed separately and then fixed into one.

[0026] Preferably, the outer diameter of the intracavitary rib when unfolded is smaller than the inner diameter of the support bracket when in the expanded state, thereby providing a cavity for the passage of blood and ensuring smooth passage of blood to provide blood supply to the nervous system.

[0027] Preferably, the supporting bracket and the intracavitary umbrella ribs are both made of shape memory alloy through laser cutting, sandblasting, electrolytic polishing and heat treatment.

[0028] Preferably, the distal embolic protection device further includes a pusher spring secured to the delivery guidewire and positioned between the proximal end of the intracavitary rib and the proximal end of the support stent. Therefore, when a free thrombus is detected near the first opening of the support stent, the delivery guidewire can be rotated to generate a vortex in the pusher spring, pushing the free thrombus near the first opening into the lumen of the protection umbrella, thereby improving capture efficiency.

[0029] Preferably, the distal embolic protection device further comprises a guidewire development spring, and the guidewire development spring is fixed to the distal end of the delivery guidewire.

[0030] Preferably, the guidewire development spring is made of a radiopaque metal material and is fixed to the distal end of the delivery guidewire by laser welding or brazing.

[0031] Preferably, the guide wire development spring is made of gold, platinum, tungsten or an alloy of at least two of the foregoing.

[0032] Preferably, the delivery guidewire comprises a grinding section and a coating section, the grinding section being more flexible than the coating section, and the guidewire development spring, the intracavitary rib, and the pusher spring are all fixed to the grinding section. This ensures that the delivery guidewire possesses a more flexible distal end structure while maintaining its pushability, ensuring good bending ability within tortuous blood vessels and protecting the vessel wall.

[0033] Preferably, the delivery guide wire is formed of shape memory alloy or stainless steel wire, and the grinding section has multiple tapered sections formed by grinding, which ensures the delivery guide wire's pushing ability while having a softer distal structure; the coating section is sequentially coated with a plastic coating, a hydrophilic coating or a hydrophobic coating to make the delivery guide wire have better smoothness.

[0034] Preferably, the distal end of the delivery guidewire has a guidewire tip, and the guidewire tip has a smooth fusion head to protect the blood vessel wall.

[0035] Compared with the prior art, the distal embolism protection device of the present invention has a protective umbrella and intracavitary umbrella ribs arranged on the delivery guide wire, wherein the protective umbrella includes a support bracket and a coating fixed to the distal end of the support bracket and adhered to the outside of the support bracket, and a plurality of holes are opened on the coating, and a layer of filtering structure is formed by the support bracket and the coating, and the intracavitary umbrella ribs are fixed in the support bracket and have a hollow structure, thereby forming another layer of filtering structure. First, the intraluminal ribs filter some larger free thrombi, and then the membrane captures smaller free thrombi, effectively improving the accumulation of thrombi in the lumen of the umbrella, reducing the probability of clogging the mesh / micropores of the umbrella, and providing spaces for blood flow, thereby ensuring adequate blood supply to the nervous system. Second, the support stent and intraluminal ribs are coaxially arranged with the delivery guidewire, which strengthens the support of the umbrella, making the support stent less likely to tilt, improving the stability of the umbrella within the blood vessel, and ensuring effective capture of free thrombi. Third, the provision of two first openings not only reduces the interference of the opening position of the umbrella on thrombi, but also greatly improves the thrombus capture efficiency based on the coaxial structure. Moreover, even if the umbrella tilts and causes the first opening on one side to be blocked by the vessel wall, the first opening on the other side can still provide an effective capture channel equivalent to the entire cross-sectional area of ​​the vessel, further ensuring thrombus capture efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic structural diagram of the distal embolic protection device of the present invention.

[0037] Figure 2a yes Figure 1 Schematic diagram of the structure from another angle.

[0038] Figure 2b yes Figure 2a Enlarged schematic diagram of part A.

[0039] Figure 3 yes Figure 1 Top view of .

[0040] Figure 4 yes Figure 1 Schematic diagram of the structure of the umbrella.

[0041] Figure 5 yes Figure 4 Schematic diagram of the structure of the support bracket.

[0042] Figure 6 yes Figure 4 Schematic diagram of the structure of the support bracket from another angle.

[0043] Figure 7 yes Figure 6 Top view of .

[0044] Figure 8 yes Figure 6 side view.

[0045] Figure 9 yes Figure 6 Top view of the device in the crimped state.

[0046] Figure 10 yes Figure 1 Schematic diagram of the structure of the coating.

[0047] Figure 11 yes Figure 10 Top view of .

[0048] Figure 12 yes Figure 1 Schematic diagram of the structure of the intracavity umbrella ribs.

[0049] Figure 13 yes Figure 12 side view.

[0050] Figure 14 yes Figure 12 Schematic diagram of the structure in which the intracavitary umbrella rib is fixed to the delivery guide wire.

[0051] Figure 15 yes Figure 1 Schematic diagram of the structure of the delivery guide wire.

[0052] Figure 16 yes Figure 15 A partial enlarged schematic diagram.

[0053] Figure 17 It is a schematic diagram of the interception state of the distal embolic protection device of the present invention. DETAILED DESCRIPTION

[0054] The embodiments of the present invention will now be described with reference to the accompanying drawings, in which similar element numbers represent similar elements. It should be noted that the orientation descriptions involved in the present invention, such as the orientations or positional relationships indicated by up, down, left, right, front, and back, are all based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the technical solutions of the present application or / and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. The first, second, etc. described are only used to distinguish technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0055] It should also be pointed out that the proximal end involved in this application refers to the end close to the operator during the operation, and the distal end refers to the end far away from the operator during the operation.

[0056] Combine Figures 1-17 As shown, the present invention provides a coaxial distal embolic protection device 1, which not only reduces the interference of the connecting rod of the existing coaxial protection device, thereby improving the efficiency of thrombus capture, but also designs a double-layer inner cavity structure, thereby effectively reducing the blockage of the mesh / micropores and ensuring safety in clinical use.

[0057] Continue to combine Figures 1-17 As shown, in one embodiment of the present invention, the distal embolic protection device 1 includes a delivery guidewire 100, a protective umbrella 200, and an intracavitary umbrella rib 300. The protective umbrella 200 is coaxially mounted on the delivery guidewire 100, and has two first openings 210a at its proximal end, symmetrically arranged along the central axis of the protective umbrella 200. A hole 220a is defined at the distal end of the protective umbrella 200. The intracavitary umbrella rib 300 is coaxially mounted on the delivery guidewire 100 and positioned within the protective umbrella 200. The intracavitary umbrella rib 300 is hollow and has a second opening 300a, which faces the distal end of the protective umbrella 200. In the present application, the protective umbrella 200 and the intracavitary umbrella rib 300 are coaxially arranged on the delivery guidewire 100, thereby improving the stability of both in the blood vessel and preventing them from tilting during use. The provision of the two first openings 210a not only reduces the interference of the opening position of the protective umbrella 200 on the thrombus, thereby greatly improving the efficiency of thrombus capture, but also, even if the protective umbrella 200 tilts and causes the first opening 210a on one side to be blocked by the blood vessel wall, the first opening 210a on the other side can still provide an effective capture channel equivalent to the entire cross-sectional area of ​​the blood vessel, further ensuring the efficiency of thrombus capture. Furthermore, the use of the intracavitary umbrella rib 300 and the protective umbrella 200 to form a double-layer filtering structure effectively reduces the probability of mesh / micropore blockage, thereby ensuring adequate blood supply to the nervous system.

[0058] The following combination Figure 1-3 、 Figure 14 As shown, in a preferred embodiment, the distal embolic protection device 1 further includes a push spring 400, which is fixed to the delivery guide wire 100 and located between the proximal end of the intracavitary rib 300 and the proximal end of the protective umbrella 200. For example, the push spring 400 is fixed to the delivery guide wire 100 by welding, bonding or other fixing methods, which are not specifically limited here. The length of the push spring 400 preferably extends from the proximal end of the intracavitary rib 300 to the proximal end of the protective umbrella 200, as shown in FIG. Figure 1 During use, if a free thrombus is found near the opening of the protective umbrella 200, the delivery guide wire 100 can be rotated to drive the pusher spring 400 to generate a vortex, pushing the free thrombus near the opening of the protective umbrella 200 into the inner cavity of the protective umbrella 200, thereby further improving the capture efficiency.

[0059] The following combination Figures 1-11 、 Figure 17 As shown, in one embodiment of the present invention, the protective umbrella 200 includes a support bracket 210 and a coating 220. The support bracket 210 is coaxially arranged on the delivery guide wire 100, and the support bracket 210 has a gripping state and an expanded state. The coaxial connection of the support bracket 210 improves its stability in the blood vessel, thereby effectively avoiding the situation where the first opening 210a is not coaxial with the blood vessel cavity. At the same time, the support bracket 210 is a hollow structure and two first openings 210a are provided at its proximal end. The two first openings 210a are symmetrically arranged along the central axis of the support bracket 210, that is, the two first openings 210a are provided on both sides of a plane passing through the central axis of the support bracket 210, and the length direction of each first opening 210a extends along the central axis direction of the support bracket 210, and the surface where each first opening 210a is located is at an angle to the cross-section of the blood vessel, as shown in FIG. Figure 17 In this embodiment, each first opening 210a has a larger width in the middle and smaller widths at both ends. Specifically, on the projection surface of the aforementioned plane, each first opening 210a is in the shape of a shuttle, as shown in FIG. Figure 4-5 As shown. This shape setting reduces interference near the first opening 210a, thereby greatly improving the capture efficiency of thrombus. Of course, the first opening 210a is not limited to a spindle shape. For example, it can be set to a wedge shape or other shapes that are conducive to the entry of thrombus. In addition, the two oppositely arranged first openings 210a, even if the support stent 210 is tilted and the first opening 210a on one side is blocked by the blood vessel wall, the first opening 210a on the other side can still provide an effective capture channel equivalent to the entire cross-sectional area of ​​the blood vessel, further ensuring the capture efficiency of thrombus.

[0060] In this embodiment, the coating 220 is fixed to the distal end of the support stent 210 and adheres to the outside of the support stent 210, and the coating 220 wraps a portion of the support stent 210, that is, the proximal portion of the support stent 210 is exposed outside the coating 220. The coating 220 is provided with a plurality of holes 220a, so that small free thrombi that enter the support stent 210 are captured by the coating 220, and the holes 220a ensure that blood can flow normally. In addition, the coating 220 can shrink and expand with the support stent 210, thereby placing the protective umbrella 200 in a compressed state and an expanded state. In the compressed state, the distal embolic protection device 1 can be inserted into or withdrawn from the blood vessel. In the expanded state, the protective umbrella 200 is placed at the distal end of the blood flow at the lesion site to capture free thrombus clots.

[0061] The following combination Figure 4-Figure 9As shown, in one embodiment of the present invention, the support stent 210 has a fusiform structure when in an expanded state, thereby effectively increasing the surface area of ​​adhesion and enhancing its wall adhesion performance, making it less likely to tilt during use. Furthermore, the release and retraction of the protective umbrella 220 is achieved through the transmission of force via the delivery guidewire 100. The fusiform support stent 210 can keep the delivery guidewire 100 centered within the stent segment, further facilitating the operation of the device.

[0062] Specifically, when the support stent 210 is in an expanded state, it includes a coaxial cylindrical section 210b and tapered sections 210c disposed at either end of the cylindrical section 210b. Both tapered sections 210c gradually narrow in a direction away from the cylindrical section 210b. The support stent 210 is connected to the delivery guidewire 100 via the two tapered sections 210c. Furthermore, the first opening 210a is formed in the proximal tapered section 210c. The cylindrical section 210b of the support stent 210 adheres to the inner wall of the blood vessel, thereby increasing the adherence area and enhancing its adherence performance, making the support stent 210 less susceptible to tilting.

[0063] Continue to combine Figure 4-Figure 9 As shown, in this embodiment, structurally, the support stent 210 comprises a plurality of first branches 211, which are staggered to form a mesh-like hollow structure. The distal end of the support stent 210 is covered with a coating 220, leaving the proximal end of the support stent 210 hollow, facilitating the effective capture of free thrombi. The first branches 211 are deformable and repositionable, thereby enabling the support stent 210 to transition between a compressed state and an expanded state.

[0064] More specifically, the first branch rod 211 includes a proximal connecting rod 2111, a middle connecting rod 2112 and a distal connecting rod 2113. Among them, multiple middle connecting rods 2112 are staggered and connected to form a mesh hollow structure, and the middle connecting rod 2112 forms the cylindrical section 210b after expansion. At least two proximal connecting rods 2111 are connected to the middle connecting rod 2112 to form the first opening 210a. In a specific embodiment, two proximal connecting rods 2111 are provided, and the two proximal connecting rods 2111 are relatively connected to one end of the middle connecting rod 2112, or in other words, the two proximal connecting rods 2111 are relatively connected to one end of the cylindrical section 210b, and two first openings 210a are formed between the two proximal connecting rods 2111. In other words, in the plane P1 (such as Figure 8 As shown in FIG), two first openings 210a are formed on both sides of the Figure 5As shown. This structure forming the first opening 210a reduces the number of rods supporting the proximal end of the stent 210, reducing interference with thrombi and thereby improving thrombus capture efficiency. Multiple distal connecting rods 2113 are connected to the other end of the middle connecting rod 2112 at intervals along the circumference. In other words, multiple distal connecting rods 2113 are connected to the other end of the cylindrical segment 210b at intervals along the circumference. The multiple distal connecting rods 2113 gradually converge to facilitate installation with the delivery guidewire 100.

[0065] Combine Figure 7 、 Figure 9 As shown, in one embodiment, a plurality of first branches 211 are staggered and connected to form a first closed-loop mesh 2111a, a second closed-loop mesh 2112a, an open-loop mesh 2112d, a third closed-loop mesh 2112b, a fourth ring-shaped mesh 2112c, and a fifth closed-loop mesh 2113a. Specifically, a plurality of middle connecting rods 2112 are staggered and connected to form a second closed-loop mesh 2112a, an open-loop mesh 2112d, a third closed-loop mesh 2112b, and a fourth ring-shaped mesh 2112c. In other words, the cylindrical section 210b is composed of the second closed-loop mesh 2112a, the open-loop mesh 2112d, the third closed-loop mesh 2112b, and the fourth ring-shaped mesh 2112c. The open-loop mesh 2112d is provided with an assembly branch 214 (described later). Unlike the conical protective umbrella in the prior art, the cylindrical section 210b of the support bracket 210 in the present application can better fit the blood vessel wall, is not easy to tilt, and can keep the delivery guide wire 100 in the center of the bracket section, which is more conducive to the operation of the device. In addition, the first closed-loop mesh 2111a is formed by two proximal connecting rods 2111. When the support bracket 210 is in an expanded state, the two proximal connecting rods 2111 are both curved, so that the first closed-loop mesh 2111a opens to form a first opening 210a. At the distal end of the support bracket 210, a fifth closed-loop mesh 2113a is formed by a plurality of distal connecting rods 2113 arranged at intervals. It can be understood that the number of the open-loop mesh and the closed-loop mesh is not limited to that in this embodiment, and can be flexibly increased or decreased according to the needs of the specific product.

[0066] Recombination Figure 1-3 、 Figure 6-Figure 9As shown, in one embodiment of the present invention, the support stent 210 further includes a coaxially arranged proximal limiting ring 212 and a distal limiting ring 213, wherein the proximal conical section 210c is connected to the proximal limiting ring 212, and the proximal conical section 210c is connected to the distal limiting ring 213. Structurally, two proximal connecting rods 2111 are connected to the proximal limiting ring 212, and a plurality of distal connecting rods 2113 are connected to the distal limiting ring 213. When installed on the delivery guide wire 100, the proximal limiting ring 212 and the distal limiting ring 213 are respectively sleeved on the outside of the delivery guide wire 100, thereby conveniently realizing the coaxial connection between the support stent 210 and the delivery guide wire 100, improving the stability of the support stent 210 in the blood vessel, and making the support stent 210 less likely to tilt.

[0067] In the present invention, at least the first branch 211 is formed by shape memory alloys (SMA), for example, by laser cutting, sandblasting, electrolytic polishing, and heat treatment of nickel-titanium shape memory alloy. Of course, it can also be made of other shape memory alloys. Since shape memory alloy (SMA) can automatically restore its own plastic deformation to its original shape at a certain temperature, the support bracket 210 can be more convenient and smooth in transition between the gripping state and the expanded state. In addition, the proximal limit ring 212 and the distal limit ring 213 can be formed of shape memory alloy (SMA) or other materials, which are not limited here.

[0068] The following combination Figure 1-4 、 Figure 10-11 As shown, in one embodiment of the present invention, the covering 220 includes a distal ring 221 and an umbrella cover 222 fixed to the distal ring 221. The two can be integrally formed or separately formed and then fixedly connected. The distal ring 221 is fixed to the distal end of the support bracket 210, and the umbrella cover 222 is attached to the outside of the support bracket 210, specifically to the conical section 210c and a portion of the cylindrical section 210b at the distal end of the support bracket 210. That is, the shape of the umbrella cover 222 is the same as the shape of the conical section 210c and the cylindrical section 210b at the distal end of the support bracket 210, thereby forming the protective umbrella 200.

[0069] See Figure 10-11 As shown, in this embodiment, the umbrella cover 222 also includes a cone portion 2221 and a cylindrical portion 2222. The tip of the cone portion 2221 is fixed to the distal ring 221. The cone portion 2221 is attached to the outside of the conical section 210c at the distal end of the support bracket 210, and the cylindrical portion 2222 is attached to the outside of the cylindrical section 210b. Figure 4-5The umbrella cover 222 can be attached to the support bracket 210 by heat shrinking, bonding or sewing with PP sutures, and other methods can also be used.

[0070] Continue to read Figure 10-11 As shown, in this embodiment, the hole 220a is provided at least in the cone portion 2221. Since thrombi tend to accumulate near the central axis of the cone portion of the protective umbrella 200, this location of the hole 220a can filter out small free thrombi while ensuring sufficient blood flow to provide blood supply to the nervous system. Of course, the hole 220a can also be provided in the cylindrical portion 2222.

[0071] In a preferred embodiment, the diameter of the holes 220a on the coating 220 gradually increases from the distal end to the proximal end along the central axis C of the support bracket 210. In other words, since the holes 220a are located in the cone portion 2221, that is, the diameter of the holes 220a gradually increases in the direction away from the central axis C of the umbrella cover 222. In the same cross section P2 perpendicular to the central axis C of the support bracket 210 (also the central axis C of the umbrella cover 222), the diameters of the holes 220a are the same, as shown in FIG. Figure 11 As shown. Because thrombi tend to accumulate near the central axis of the cone portion 2221 of the protective umbrella 200, this aperture configuration of the holes 220a can filter out smaller free thrombi while ensuring sufficient blood flow to supply the nervous system. In this embodiment, the holes 220a are formed in the umbrella cap 222 by laser processing; however, other processing methods are also possible.

[0072] In the present invention, the coating 220 is preferably a plastic film, for example, TPU (Thermoplastic polyurethanes), PTFE (Polytetrafluoroethylene) and other plastic films, but is certainly not limited to the aforementioned materials.

[0073] The following combination Figure 1-Figure 3 As shown, in one embodiment of the present invention, the protective umbrella 200 further includes a head-end developing collar 230, which is coaxially sleeved outside the distal retaining ring 213, thereby pressing the coating 220 between the head-end developing collar 230 and the distal retaining ring 213. Specifically, the distal ring 221 of the coating 220 is fixed between the head-end developing collar 230 and the distal retaining ring 213. The head-end developing collar 230 not only effectively secures the coating 220 to the support bracket 210 but also facilitates the positioning of the protective umbrella 200 within the body.

[0074] Combine Figure 4-Figure 8 As shown, the distal stop ring 213 includes a stepped first tube segment 2131 and a second tube segment 2132. The outer diameter of the first tube segment 2131 is smaller than that of the second tube segment 2132. The distal ring 221 of the coating 220 is sleeved over the distal stop ring 213, with its umbrella 222 extending toward the proximal end of the support bracket 210. The head end developing ring 230 is coaxially sleeved over the first tube segment 2131 and abuts the end surface of the second tube segment 2132, thereby stably pressing the distal ring 221 of the coating 220 between the head end developing ring 230 and the distal stop ring 213, thereby stably fixing the coating 220 to the distal end of the support bracket 210.

[0075] In the present invention, the head-end developing collar 230 is made of a metal material that is opaque to X-rays. For example, the head-end developing collar 230 can be made of gold, platinum, tungsten, or an alloy of at least two of the aforementioned materials. Of course, the materials are not limited to the aforementioned materials. The head-end developing collar 230 allows for intuitive visualization of the position of the protective umbrella 200 within the body, thereby facilitating positioning of the protective umbrella 200 within the body.

[0076] The following combination Figure 1-Figure 5 As shown, in one embodiment of the present invention, the protective umbrella 200 further includes a bracket developing spring 240 , and the supporting bracket 210 is provided with an assembly branch rod 214 , and the bracket developing spring 240 is fixed to the assembly branch rod 214 and exposed outside the coating 220 .

[0077] Combine Figure 6-Figure 8 As shown, the assembly branch rod 214 is fixed on the middle connecting rod 2112, and the position of the assembly branch rod 214 is set to form an open-loop mesh 2112d. The bracket developing spring 240 is inserted into the assembly branch rod 214 and fixed by laser welding. Of course, it can also be fixed in other ways. The bracket developing spring 240 is also made of a metal material that is not transparent to X-rays. For example, it is made of gold, platinum, tungsten or an alloy of at least two of the above. Therefore, the bracket developing spring 240 can be observed under X-rays, thereby intuitively observing the deployment status and corresponding position of the protective umbrella 200, providing guidance for subsequent operations.

[0078] Combine Figure 6-8 As shown, in one embodiment of the present invention, two assembly branches 214 are provided, and the two assembly branches 214 are symmetrically arranged along the central axis of the support bracket 210. Specifically, the two assembly branches 214 are arranged in a plane P1 passing through the two proximal connecting rods 2111 and the central axis of the support bracket 210, as shown in FIG. Figure 8 shown.

[0079] Combine Figure 4-5As shown, in this embodiment, the two bracket developing springs 240 are respectively fixed on the two assembly branches 214. In addition, the connecting line of the head end developing ring 230 and the two bracket developing springs 240 forms an isosceles triangle developing effect (as shown in FIG. Figure 4 As shown), the operator can easily determine the deployment status, tilt, release position, etc. of the protective umbrella 200 according to the direction of the blood vessels and the relative positions of the three points, and can make timely adjustments.

[0080] The following combination Figure 1-3 、 Figure 12-14 As shown, in one embodiment of the present invention, the intracavitary ribs 300 are specifically fixed within the covering 220. The intracavitary ribs 300 include a rib retaining ring 310 and a plurality of second branches 320. Each second branch 320 is fixed to the rib retaining ring 310 at intervals along the circumference of the rib retaining ring 310, and each second branch 320 is preferably evenly distributed along the circumference of the rib retaining ring 310. The end of each second branch 320 away from the rib retaining ring 310 forms a second opening 300a. During installation, the rib retaining ring 310 is coaxially fixed to the delivery guide wire 100, with the second opening 300a facing the distal end of the support bracket 210, that is, toward the tapered portion 2221 of the covering 220. The intracavitary ribs 300 increase the support of the protective umbrella 200, making it less likely for the protective umbrella 200 to tilt or fail to fully deploy. The intracavitary ribs 300 collapse as the support bracket 210 is compressed and expand as the support bracket 210 expands. Furthermore, the outer diameter of the expanded intracavitary ribs 300 is slightly smaller than the inner diameter of the support bracket 210 in its expanded state. Thus, the intracavitary ribs 300 and the membrane 220 form a double-layer filtering structure. First, the intracavitary ribs 300 filter larger free thrombi, preventing them from accumulating in the tapered portion of the protective umbrella 200. The gaps between the intracavitary ribs 300 and the support bracket 210 provide a cavity for blood flow, ensuring smooth blood flow and supplying the nervous system. Then, the membrane 220 captures smaller free thrombi, which then pass through the pores 220a in the membrane 220, ensuring adequate blood supply to the nervous system during surgery. Compared to conventional single-layer filtering structures, the double-layer filtering structure of the present application significantly reduces the accumulation of free thrombi in the umbrella cavity and effectively prevents clogging of the mesh or micropores in the membrane 220.

[0081] In this embodiment, each second branch rod 320 and the rib retaining ring 310 are preferably an integrally formed structure, for example, formed by cutting and shaping a metal pipe. Of course, each second branch rod 320 and the rib retaining ring 310 can also be formed separately and then fixed to form a whole.

[0082] In the present invention, at least the second branch 320 is formed from a shape memory alloy (SMA), for example, a nickel-titanium shape memory alloy that is laser cut, sandblasted, electropolished, and heat-treated to finalize the shape. Of course, the rib retaining ring 310 can also be formed from a shape memory alloy (SMA). Because SMA automatically returns to its original shape after plastic deformation at a specific temperature, this makes the ribs 300 in the cavity more convenient and smooth to fold and unfold.

[0083] The following combination Figure 1-3 、 Figure 15-16 As shown, in one embodiment of the present invention, the distal embolic protection device 1 further includes a guidewire development spring 500, which is fixed to the distal end of the delivery guidewire 100. The guidewire development spring 500 is made of an X-ray opaque metal material, such as gold, platinum, tungsten, or an alloy of at least two of the foregoing, but is not limited to these materials. The guidewire development spring 500 is fixed to the distal end of the delivery guidewire 100 by laser welding, brazing, or other fixing methods.

[0084] Specifically, the delivery guidewire 100 is sequentially threaded through the proximal retaining ring 212 of the protective umbrella 200, the pusher spring 400, the endoscopic skeleton 300, the distal retaining ring 213 of the protective umbrella 200, and the inner cavity of the guidewire development spring 500, while ensuring that the delivery guidewire 100 is coaxial with the aforementioned components. The threading method between the delivery guidewire 100 and the aforementioned components is conventional in the art.

[0085] The following combination Figure 15-16 As shown, in one embodiment of the present invention, the delivery guidewire 100 includes a grinding section 110, a coating section 120, and a guidewire tip 130. The guidewire tip 130 is located at the distal end of the delivery guidewire 100, and the guidewire tip 130 has a smooth melt head, which plays a role in protecting the blood vessel wall. The guidewire development spring 500 is fixed to the distal end of the delivery guidewire 100 and is attached to the guidewire tip 130. In addition, the flexibility of the grinding section 110 is greater than that of the coating section 120, and the grinding section 110 and the coating section 120 are arranged at intervals. Specifically, the position where the guidewire development spring 500, the intracavitary rib 300, and the pusher spring 400 are fixed is the grinding section 110, and the remaining positions are the coating section 120. In this way, while ensuring the pushing ability of the delivery guidewire 100, the delivery guidewire 100 has a softer distal structure, ensuring good bending ability in tortuous blood vessels and protecting the blood vessel wall.

[0086] In this embodiment, the delivery guidewire 100 is formed from a nickel-titanium shape memory alloy or stainless steel wire. The grinding segment 110 is ground into multiple tapered segments using a grinder, thereby providing a more flexible distal end structure while maintaining the pushability of the delivery guidewire 100. The coating segment 120 is formed by coating the nickel-titanium shape memory alloy or stainless steel wire with a plastic coating, then applying a hydrophilic or hydrophobic coating to enhance the smoothness of the coating segment 120.

[0087] It is understandable that the delivery guidewire 100 can also be set to other structures. The delivery guidewire 100 is a conventional structure in the art and will not be described in detail.

[0088] Combine again below Figures 1-17 As shown, the working principle and status of the distal embolic protection device 1 of the present invention are explained.

[0089] When in use, the protective umbrella 200 of the distal embolic protection device 1 is first inserted into the blood vessel 2 and placed at the distal end of the blood flow of the lesion site, such as Figure 17 During the interventional procedure, the protective umbrella 200 and the intracavitary ribs 300 are both retracted. Furthermore, the guidewire development spring 500, the head-end development collar 230, and the support development spring 240 all indicate the position of the protective umbrella 200 within the body, thereby facilitating positioning of the protective umbrella 200 within the body. The interventional procedures and methods for the protective umbrella 200 are conventional in the art and will not be described in detail.

[0090] Combine Figure 1-3 、 Figure 17 As shown, after the protective umbrella 200 is positioned distal to the blood flow of the lesion, the protective umbrella 200 and the intracavitary ribs 300 are opened. Specifically, the support bracket 210 transitions from a compressed state to an expanded state, thereby causing the membrane 220 attached to the support bracket 210 to expand. As the support bracket 210 expands, the intracavitary ribs 300 also unfold. The second openings 300a of the unfolded intracavitary ribs 300 face the conical portion 2221 of the membrane 220, and the intracavitary ribs 300 are positioned within the membrane 220. During this opening process, the support visualization spring 240 allows visual observation of the full deployment of the protective umbrella 200 and its position within the body, providing guidance for subsequent operations.

[0091] Combine Figure 4-Figure 8As shown, when the protective umbrella 200 is fully opened, the inflated protective umbrella 200 takes on a fusiform structure, with its cylindrical section 210b adhering to the inner wall of the blood vessel 2, thereby increasing the wall-adhering area and enhancing its wall-adhering performance, making the protective umbrella 200 less likely to tilt. At the same time, the two first openings 210a at the proximal end of the protective umbrella 200 are symmetrically arranged along the central axis of the support bracket 210. Specifically, the two first openings 210a are arranged on both sides of the plane P1 passing through the two proximal connecting rods 2111, as shown in FIG. Figure 5 、 Figure 8 As shown, even if the support bracket 210 tilts, causing the first opening 210a on one side to be blocked by the wall of the blood vessel 2, the first opening 210a on the other side can still provide an effective capture channel equivalent to the cross-sectional area of ​​the entire blood vessel 2, thereby ensuring the effective capture of free thrombi. Furthermore, only two proximal connecting rods 2111 are provided between the two first openings 210a, resulting in fewer rods surrounding the first openings 210a, reducing interference with thrombi at the entrance and thereby improving thrombus capture efficiency. Furthermore, the deployed intracavitary ribs 300 also enhance the support of the protective umbrella 200, making it less susceptible to tilting.

[0092] like Figure 17 As shown, during an interventional procedure, the protective umbrella 200 of this device expands and anchors to the inner wall of the blood vessel 2, maintaining the position of the delivery guidewire 100. This device functions as the delivery guidewire 100 during the procedure, allowing the introduction of a balloon 4 or stent as needed. The balloon 4 can be used to dilate the lesion. Specifically, the balloon 4 can be inserted along the delivery guidewire 100 to dilate or implant a stent. During the expansion of the lesion by the balloon 4, free thrombi 3 are generated. These thrombi 3 are captured by the double-layer filtering structure formed by the intraluminal ribs 300 and the protective umbrella 200. Specifically, as blood flows, blood and free thrombi 3 flow into the protective umbrella 200 through the first opening 210a. The intraluminal ribs 300 within the umbrella cavity first filter larger free thrombi 3. Smaller free thrombi 3 enter the tapered section 210c of the protective umbrella 200 and are captured by the coating 220. At the same time, blood flows into the cover 220 through the gaps on the intracavitary ribs 300 and the gaps between the intracavitary ribs 300 and the inner wall of the cover 220, and then flows out through the holes 220a on the cover 220, thereby providing sufficient cavity for the passage of blood. Compared with the single-layer filter structure in the prior art, the double-layer filter structure of the present application greatly improves the problem of mesh / micropore blockage, thereby ensuring sufficient blood supply to the nervous system.

[0093] Recombination Figure 1-3 、 Figure 17As shown, during the interventional treatment, blood flow near the protective umbrella 200 slows down. At this point, there is insufficient blood flow momentum to carry the free thrombus 3 into the interior of the protective umbrella 200, and free thrombus 3 may be attached near the first opening 210a. In this case, the delivery guidewire 100 can be rotated to drive the pusher spring 400 to generate a vortex, pushing the free thrombus 3 near the first opening 210a of the protective umbrella 200 into the inner cavity of the protective umbrella 200, thereby further improving capture efficiency.

[0094] After treatment is complete, the support frame 210 is moved from its expanded state to a compressed state. During this process, the support frame 210 causes the coating 220 attached thereto to contract, while simultaneously causing the internal ribs 300 to collapse. The protective umbrella 200 is then removed from the body using the delivery guidewire 100. The process and method for collapsing and removing the protective umbrella 200 are conventional in the art and will not be described in detail.

[0095] To sum up, in the distal embolic protection device 1 of the present invention, a protective umbrella 200 and an intracavitary umbrella rib 300 are coaxially arranged on the delivery guide wire 100, wherein the protective umbrella 200 includes a support bracket 210 and a coating 220 fixed to the distal end of the support bracket 210 and adhered to the outside of the support bracket 210, and a plurality of holes 220a are opened on the coating 220, and a layer of filtering structure is formed by the support bracket 210 and the coating 220, and the intracavitary umbrella rib 300 is fixed in the support bracket 210 and has a hollow structure, thereby forming another layer of filtering structure. The double-layer filtering structure of the present application has the following effects: first, the intracavitary umbrella ribs 300 are used to filter some large-sized free thrombi, and then the covering membrane 220 captures small-sized free thrombi, thereby effectively improving the accumulation of thrombus clots in the inner cavity of the protective umbrella 200, reducing the probability of clogging of the mesh / micropores of the protective umbrella 200, providing a cavity for the passage of blood flow, and thus ensuring sufficient blood supply to the nervous system; secondly, the supporting bracket 210 and the intracavitary umbrella ribs 300 are coaxially arranged with the delivery guide wire 100, which strengthens the support of the protective umbrella 200, so that the supporting bracket 210 does not It is easy to tilt, which improves the stability of the protective umbrella 200 in the blood vessel 2 and ensures the effective capture of free thrombi. Furthermore, the provision of the two first openings 210a not only reduces the interference of the opening position of the protective umbrella 200 on the thrombus, but also greatly improves the capture efficiency of free thrombi on the basis of the coaxial structure. Moreover, even if the protective umbrella 200 tilts and causes the first opening 210a on one side to be blocked by the wall of the blood vessel 2, the first opening 210a on the other side can still provide an effective capture channel equivalent to the cross-sectional area of ​​the entire blood vessel 2, further ensuring the capture efficiency of free thrombi.

[0096] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. Equivalent changes made within the scope of the patent application are still within the scope covered by the present invention.

Claims

1. A distal embolic protection device, characterized in that: include: Delivery guidewire; A protective umbrella includes a support bracket and a coating, wherein the support bracket has a hollow structure and is provided with two first openings at the proximal end, the two first openings are symmetrically arranged along the central axis of the support bracket, the support bracket is coaxially passed through the delivery guide wire, and the support bracket has a compressed state and an expanded state, the coating is fixed to the distal end of the support bracket and adheres to the outside of the support bracket, the coating wraps a portion of the support bracket, the coating can shrink and expand with the support bracket, and a plurality of holes are opened on the coating; an intracavitary rib, wherein the intracavitary rib is a hollow structure and has a second opening, the intracavitary rib is coaxially fixed to the delivery guidewire and is located in the support bracket, the second opening faces the distal end of the support bracket, the intracavitary rib can be folded and unfolded with the support bracket, and the outer diameter of the intracavitary rib when unfolded is smaller than the inner diameter of the support bracket when in the expanded state; The intracavitary ribs and the covering membrane form a double-layer filtering structure, and blood flows into the covering membrane through the gaps on the intracavitary ribs and the gaps between the intracavitary ribs and the inner wall of the covering membrane.

2. The distal embolic protection device according to claim 1, wherein: The first opening is fusiform or wedge-shaped, the length direction of each first opening is consistent with the axial direction of the central axis of the support stent, and the surface where each first opening is located forms an angle with the cross-section of the blood vessel.

3. The distal embolic protection device according to claim 1, wherein: The support bracket includes a coaxially arranged cylindrical section and tapered sections arranged at both ends of the cylindrical section, and the first opening is formed in one of the tapered sections.

4. The distal embolic protection device according to claim 1, wherein: The support bracket includes a coaxially arranged proximal limiting ring, a distal limiting ring and a plurality of first branch rods connected therebetween. The plurality of first branch rods are staggered to form a mesh hollow structure. The proximal limiting ring and the distal limiting ring are respectively sleeved on the outside of the delivery guide wire.

5. The distal embolic protection device according to claim 4, wherein: The protective umbrella also includes a head end developing sleeve, which is coaxially sleeved outside the distal end limiting ring, thereby pressing the coating tightly between the head end developing sleeve and the distal end limiting ring.

6. The distal embolic protection device according to claim 5, wherein: The protective umbrella also includes two bracket developing springs, which are fixed on the supporting bracket and symmetrically arranged along the central axis of the supporting bracket, and the connecting line of the head end developing ring and the two bracket developing springs forms an isosceles triangle.

7. The distal embolic protection device according to any one of claims 1 to 6, characterized in that: In the direction from the distal end to the proximal end along the central axis of the support bracket, the apertures of the holes on the covering membrane gradually increase, and in the same cross section perpendicular to the central axis of the support bracket, the apertures of the holes are the same.

8. The distal embolic protection device according to any one of claims 1 to 6, characterized in that: The covering film includes a distal ring and an umbrella cap fixed to the distal ring. The distal ring is fixed to the distal end of the support bracket, and the umbrella cap is attached to the outside of the support bracket.

9. The distal embolic protection device according to claim 8, wherein: The umbrella cover includes a cone portion and a cylindrical portion. The tip of the cone portion is fixed to the distal ring. The hole is at least opened in the cone portion.

10. The distal embolic protection device according to any one of claims 1 to 6, characterized in that: The intra-cavity umbrella rib includes an umbrella rib limiting ring and a plurality of second branches, each of the second branches is fixed to the umbrella rib limiting ring at intervals along the circumference of the umbrella rib, and an end of each second branch away from the umbrella rib limiting ring forms the second opening, and the umbrella rib limiting ring is coaxially fixed to the delivery guide wire.

11. The distal embolic protection device according to any one of claims 1 to 6, characterized in that: It also includes a push spring, which is fixed to the delivery guide wire and is located between the proximal end of the umbrella rib in the cavity and the proximal end of the support bracket.

12. The distal embolic protection device according to claim 11, wherein: It also includes a guide wire development spring, which is fixed to the distal end of the conveying guide wire; the conveying guide wire includes a grinding section and a coating section, the flexibility of the grinding section is greater than the flexibility of the coating section, and the guide wire development spring, the intracavitary umbrella rib, and the push spring are all fixed to the grinding section.

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