CN118750076A - An occluder - Google Patents

Abstract

The present invention discloses an occluder, which relates to the technical field of medical devices. The occluder includes an occluding bracket and two restraining members; the occluding bracket includes an inner wall member, an outer wall member and a flow blocker filled between the inner wall member and the outer wall member, the inner wall member is connected to the two ends of the outer wall member, the inner wall member surrounds and forms a hollow channel that allows a through barrier to pass through, and the occluding bracket is lantern-shaped, columnar or irregular in shape; the two restraining members are respectively coated on the two ends of the occluding bracket along the length direction of the hollow channel, and are used to restrain the radial dimension of the hollow channel. The present invention proposes an occluder structure, which is used for filling and plugging a cavity with a through barrier inside, and can effectively reduce the incidence of internal leakage.

Description

An occluder

Technical Field

The present invention relates to the technical field of medical devices, and in particular to an occluder.

Background Art

Endovascular Abdominal Aortic Repair (EVAR) is increasingly being used in clinical practice due to its minimally invasive and safe advantages. The main complication after EVAR is endoleak. The most common type of endoleak is blood reflux into the aneurysm cavity through branch arteries (such as the lumbar artery, inferior mesenteric artery, internal iliac artery, and accessory renal artery), resulting in continuous expansion of the aneurysm cavity, and in severe cases, rupture with serious consequences.

Embolization of the responsible vessel (the inferior mesenteric artery or lumbar artery) is the most common way to treat type II endoleak. However, due to the distorted anatomical course of some collateral vessels, superselection is time-consuming and has a low success rate. In addition, there is a risk of distal vascular embolism caused by thrombus detachment from the aneurysm cavity during the treatment process. In actual clinical practice, it has been found that preventive filling of the aneurysm cavity during EVAR can also reduce the incidence of type II endoleak.

The most common abdominal aortic aneurysm is fusiform. After implantation of the covered stent, the remaining cavity surrounds the covered stent and presents an irregular structure with small gaps between the proximal and distal ends and the vascular wall and large gaps between the middle and the vascular wall. However, the occlusion devices currently on the market are difficult to effectively fill, and the incidence of type II endoleak is still high.

Summary of the invention

The main purpose of the present invention is to provide an occluder, aiming to improve the occlusion effect and reduce the incidence of type II endoleak.

To achieve the above object, the present invention provides an occluder, comprising:

A blocking bracket, comprising an inner wall component, an outer wall component and a flow blocker filled between the inner wall component and the outer wall component, wherein the inner wall component is connected to both ends of the outer wall component, the inner wall component surrounds and forms a hollow channel allowing a through-blocker to pass through, and the blocking bracket is in a lantern shape, a column shape or an irregular shape; and

Two restraining members are respectively covered on two ends of the blocking stent along the length direction of the hollow channel, and are used to restrain the radial dimension of the hollow channel.

Optionally, the inner wall member extends in at least one position along the length direction of the hollow channel toward the outer wall member to form a radially extending channel communicating with the hollow channel.

Optionally, the axial cross-section of the radially extending channel is in a strip shape, an arc shape or a T-shape.

Optionally, the flow barrier comprises at least one of a fiber membrane, a water-absorbent expandable foam material and a hydrogel material.

Optionally, the inner wall component and the outer wall component are both composed of a single-layer, double-layer or multi-layer woven mesh, and the material of the woven mesh is at least one of PPDO degradable wire, PLA degradable wire and nickel-titanium alloy wire.

Optionally, the restraining member is a film, cloth or wire.

Optionally, the film is at least one of a PPDO film, a PLA film, a PCL film, a PLCL film and a PTFE film; and/or the cloth is an elastic woven cloth made of PA or PET elastic yarn.

Optionally, the silk is at least one of PA or PET elastic silk, PPDO degradable silk, PLA degradable silk, PCL degradable silk, and PLCL degradable silk.

Optionally, both the flow blocker and the restraining member carry the material with antibacterial efficacy by at least one deposition method selected from the group consisting of immersion, co-blending electrospinning, and mixed synthesis.

Optionally, the material is at least one of triclosan, curcumin, chitosan and tetracycline hydrochloride.

In the technical solution of the present invention, the occluder includes an occluding stent and two restraining members; the occluding stent includes an inner wall member, an outer wall member and a flow obstruction filled between the inner wall member and the outer wall member, the inner wall member is connected to the two ends of the outer wall member, the inner wall member surrounds and forms a hollow channel that allows the through-blocking object to pass through, and the occluding stent is in the shape of a lantern, a column or an irregular shape; the two restraining members are respectively coated on the two ends of the occluding stent along the length direction of the hollow channel, and are used to restrain the radial dimension of the hollow channel. It can be understood that the structure of the occluder proposed in the present invention is used for filling and plugging a cavity with a through-blocking object inside. Since the occluding stent is in the shape of a lantern, a column or an irregular shape, it is adapted to the shape of the cavity or the sac, can effectively fill the gap, and improve the plugging effect, thereby helping to reduce the incidence of type II internal leakage.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

FIG1 is a schematic diagram of an application of an occluder according to an embodiment of the present invention;

FIG2 is a perspective view of an occluder according to an embodiment of the present invention;

FIG3 is a cross-sectional view of an occluder according to an embodiment of the present invention;

FIG4 is a cross-sectional view of another embodiment of the occluder of the present invention;

FIG5 is a cross-sectional view of another embodiment of the occluder of the present invention;

FIG6 is a cross-sectional view of another embodiment of the occluder of the present invention;

FIG7 is a diagram showing the preparation of antibacterial materials for the flow blocker and the restraining member in an embodiment of the occluder of the present invention;

FIG8 is a structural diagram of a wire-binding neck at one end of an occluder in an embodiment of the present invention;

FIG9 is a structural diagram of a side surface of one end of an occluder in an embodiment of the present invention;

FIG. 10 is a cross-sectional view of the side surface of one end of an occluder in an embodiment of the present invention.

Description of Figure Numbers:

10. Blocking stent; 20. Restraining member; 200. Covered stent; 11. Inner wall member; 12. Outer wall member; 13. Flow blocker; 10a. Hollow channel; 10b. Radially extending channel.

The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and/or" appearing in the full text is to include three parallel solutions. Taking "A and/or B" as an example, it includes solution A, or solution B, or a solution that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

The present invention provides an occluder for filling and sealing a cavity having a through-blocking object inside, but the present invention is not limited here.

Referring to Fig. 1 to Fig. 6, in some embodiments of the present invention, the occluder includes an occluding stent 10 and two restraining members 20; the occluding stent 10 includes an inner wall member 11, an outer wall member 12 and a flow blocker 13 filled between the inner wall member 11 and the outer wall member 12, the inner wall member 11 is connected to the outer wall member 12 at both ends, the inner wall member 11 and the outer wall member 12 can be an integral structure, or assembled from two or more parts, the inner wall member 11 surrounds a hollow channel 10a that allows a through barrier to pass through, and the occluding stent 10 is lantern-shaped, columnar or irregular in shape; the two restraining members 20 are respectively coated on both ends of the occluding stent 10 along the length direction of the hollow channel 10a, and are used to restrain the radial dimension of the hollow channel 10a. As shown in Fig. 1, the through barrier can be a coated stent 200, etc., and its shape, size, etc. are not limited. The hollow channel 10a should be designed to be adapted to the specific through barrier.

In this embodiment, the outer wall of the occluder can be viewed from the side to be lantern-shaped, column-shaped or other irregular shapes that are adapted to the shape of the cavity or the pouch. The inner wall of the occluder can be viewed from the side to be column-shaped, diamond-shaped or other irregular shapes that are adapted to the shape of the through barrier.

In this embodiment, both the inner wall component 11 and the outer wall component 12 can be woven and shaped using degradable wires or metal wires with shape memory function, so that the occluder is suitable for use in cavities or bags with penetrating barriers.

The restraining member 20 can be a film, cloth, or silk, etc., and is made of medical material, which is not specifically limited here.

It can be understood that the structure of the occluder proposed in the present invention is used for filling and plugging a cavity with a penetrating barrier inside. Since the occluding stent 10 is lantern-shaped, columnar or irregular in shape, it adapts to the shape of the cavity or the sac and can effectively fill the gap, thereby improving the plugging effect and helping to reduce the incidence of type II endoleak.

In order to improve the support stability of the occluding stent 10 and further improve the compliance of the occluding device to adapt to more application environments, referring to Figures 3 to 6, in some embodiments, the inner wall member 11 extends in at least one position along the length direction of the hollow channel 10a toward the direction close to the outer wall member 12 to form a radially extending channel 10b connected to the hollow channel 10a. In this embodiment, the axial cross-section of the radially extending channel 10b is strip-shaped, arc-shaped, or "T"-shaped, etc., which is not limited here.

It should be noted that the facade of the outer wall member 12 of the occluder should maintain continuity, and at least one portion of the inner wall member 11 is close to the outer wall member 12, which can support the outer wall member 12 and help improve the support stability of the occluder stent 10. In addition, the outer convex portion of the inner wall member 11 that forms the radial extension channel 10b increases the length of the inner wall member 11 after being straightened along the axial direction. By adjusting the length to be the same as the length of the outer wall member 12 after being straightened along the axial direction, it can be ensured that the occluder can use a small-caliber sheath tube as much as possible during interventional delivery.

In one embodiment, as shown in Fig. 3, the flow blocker 13 includes at least one of a fiber membrane, a water-absorbing expandable foam material, a hydrogel material, etc. In this way, the occluder can have better adaptability, which is conducive to improving the occlusion effect.

Mainly referring to FIG2 , in one embodiment, the inner wall member 11 and the outer wall member 12 are both composed of a single-layer, double-layer or multi-layer braided mesh, and the material of the braided mesh is at least one of PPDO degradable wire, PLA degradable wire and nickel-titanium alloy wire. This arrangement can, on the one hand, make the occluder adapt to the shape of the cavity or the pouch, and on the other hand, can solve the problem of the parts of the occluder being left in the human body after surgery and causing harm.

To ensure that the end of the tie is stretchable, referring to Figures 1 to 6, in one embodiment, the tie 20 may preferably be a film, a cloth or a thread. Specifically, the film may be at least one of PPDO film, PLA film, PCL film, PLCL film and PTFE film; the cloth may be an elastic woven cloth made of PA or PET elastic wire; the thread may be at least one of PA or PET elastic wire, PPDO degradable thread, PLA degradable thread, PCL degradable thread, PLCL degradable thread and the like.

The present invention uses a binding member 20 such as a film, cloth or wire to bind and block the openings at both ends of the stent 10, which can effectively limit the radial size of the end of the hollow channel 10a surrounded by the inner wall member 11 to accommodate the through-blocking object, and allow the through-blocking object that is a certain proportion larger than the radial size of the hollow channel 10a in the natural state without force to pass through.

In this embodiment, the length of the restraining member 20 can be the same as the circumference of the end surface of the hollow channel 10a in a natural state without force, so that it has a better restraining effect and saves material costs.

To further improve the safety of the operation, please refer to FIG. 7 . In one embodiment, the flow blocker 13 and the restraining member 20 can carry materials with antibacterial efficacy by at least one deposition method selected from the group consisting of immersion, co-blending electrospinning, and mixed synthesis.

In this embodiment, the material may be at least one of triclosan, curcumin, chitosan and tetracycline hydrochloride, etc., which are not limited here.

In a specific embodiment, the occluding stent 10 is made by weaving a 3-0 wire diameter PPDO degradable wire one by one in the cross direction into a mesh type with two ends through, and then shaping it at a high temperature of 70°C to 110°C by loading a mold. As shown in FIG2 , the occluding stent 10 includes an inner wall component 11 and an outer wall component 12, and both the inner wall component 11 and the outer wall component 12 are composed of a single-layer woven mesh. Observed from the side of the outer wall of the occluding stent 10, it is lantern-shaped.

In this embodiment, the axial ends of the blocking stent 10 should avoid retaining free degradable filaments. After the degradable filaments are woven to the axial ends, they are folded back to the middle part away from the two ends and continue to be woven in a one-press-one manner. Each fold back forms a closed loop at the axial ends. As shown in Figure 8, after 1 to 5 3-0 wire diameter PPDO degradable filaments are bundled and sequentially passed through the closed loop, the free bundles at both ends are tightened to make the inner wall of the stent form a hollow channel 10a that adapts to the through barrier, and the radial dimensions of the outlets at the axial ends are between 90% and 100% of the radial dimensions of the through barrier. After tightening, the free bundles are knotted or continue to be woven in a one-press-one manner toward the middle part away from the two ends.

In this embodiment, a PLCL film is filled between the outer wall component 12 and the inner wall component 11 of the occluding stent 10. The film is obtained by electrospinning by electrostatic spinning technology after the high molecular polymer PLCL is blended with triclosan, and can provide antibacterial effect. Preferably, its thickness ranges from 0.05mm to 0.15mm. The film is sutured to the inner side of the outer wall by 6-0 PPDO sutures against the outer wall. After the sutured film is unfolded, the length in the axial direction of the occluding stent 10 is in the range of 100% to 150% of the length of the occluding stent 10 after it is pulled into a strip.

As shown in FIG. 2 , the inner wall member 11 of the occluding stent 10 of the present embodiment protrudes toward the outer wall member 12 until it is in contact with the outer wall member 12 in the middle part where the radial length of the entire occluding stent 10 is the largest. When the protruding part is observed from the side, it is in the shape of an arc. With the junction of the inner and outer walls at the two end faces as the clamping point, the length of the continuous outer wall member 12 after being straightened along the axial direction and the length of the inner wall member 11 with the protruding part after being straightened along the axial direction are in the ratio of 100% to 105%, and shall not exceed 5 mm. This arrangement allows the outer wall of the occluding stent 10 to maintain its shape and ensure the occluding effect; in addition, this ensures that a small-caliber sheath can be used as much as possible during interventional delivery of the occluder.

When in use, the occluder of this embodiment needs to be delivered into the affected area. A small-caliber metal tube is used to penetrate the hollow channel 10a of the occluder, and the occluder is axially stretched into a long strip. The closed rings at both ends of the axial direction of the occluder are suspended on two padlock devices of the delivery device along the axial direction of the small-caliber metal tube. The padlock device, the long-shaped occluder, and the small-caliber metal tube in the long-shaped occluder are received in the large-caliber outer sheath. The guide wire is inserted into the small-caliber metal tube to guide the establishment of the delivery path. After reaching the target position, the distal padlock device of the delivery system is unlocked to release the distal end of the occluder, and the occluder is gradually released toward the proximal end by withdrawing the outer sheath until the proximal padlock device of the delivery system is finally unlocked, and the delivery system is withdrawn, retaining the guide wire that passes through the hollow channel 10a of the occluder to guide the implantation of a through barrier such as a coated stent 200. The state after implementation can be seen in Figure 1.

In another specific embodiment, the occluding stent 10 is a stent formed by weaving 144 0.06 mm nickel-titanium alloy wires into a mesh with two ends connected on a mesh weaving device, and then forming the stent at a high temperature of 500°C to 600°C through a shaping mold. The stent includes an inner wall component 11 and an outer wall component 12, both of which are composed of double-layer woven mesh. The side view of the outer wall of the stent is lantern-shaped.

As shown in FIG6 , in this embodiment, the inner wall of the occluding stent 10 protrudes in a “T” shape toward the outer wall in the middle section along the axial direction of the through channel, the width of the protruding mesh in the gap between the inner and outer walls is between 2 mm and 10 mm along the axial direction of the through channel, and the length of the mesh close to the outer wall is between 10 mm and 40 mm along the axial direction of the through channel. This arrangement can provide sufficient support for the outer wall of the stent to maintain its shape, so that the occluder can meet the occlusion requirements of endovascular repair of fusiform abdominal aortic aneurysms.

As shown in Figures 9 and 10, the occluding stent 10 of this embodiment is wrapped with an elastic PLCL film on the inner and outer walls at both ends along the axial direction of the through channel. The length of the film from the end face on the outer and inner walls is in the range of 2mm to 10mm to achieve a better binding effect. The two free edges of the film are sutured continuously on the inner and outer walls with a non-degradable suture with a diameter of 6-0 at a distance of about 1mm from the edge. The diameter of the stent graft 200 implanted in the through channel after expansion is larger than the diameter of the hollow channel 10a, which will cause the hollow channel 10a and the film coated at both ends to be stretched without being broken, greatly improving the reliability of the occluder.

In this embodiment, the pores between the inner and outer walls of the occluding stent 10 are filled with a hydrogel material that absorbs water and expands. The hydrogel material exists in two states: a dry state and a wet state that expands when exposed to water. When tetracycline hydrochloride is added to the solution of the synthetic hydrogel, it becomes powder or granular after volatilization. Because the woven mesh is made of fine filaments and multiple woven strands, it has a high density and small pores. The dry hydrogel is arranged between the inner and outer walls without leaking out. After the occluder is implanted in the body, the dry hydrogel absorbs water and expands to fill the pores between the inner and outer walls, increasing the occluder's resistance to blood flow and providing antibacterial efficacy.

The occluder of this embodiment needs to be delivered into the affected area when in use. A small-caliber metal tube is used to penetrate the hollow channel 10a of the occluder, and the occluder is axially stretched into a long strip. The axial ends of the occluder are pressed by two compression locking devices of the conveying device along the axial direction of the small-caliber metal tube. The compression locking devices, the long-shaped occluder, and the small-caliber metal tube in the long-shaped occluder are received in the large-caliber outer sheath. The guide wire is inserted into the small-caliber metal tube to guide the establishment of the delivery path. After reaching the target position, the distal compression locking device of the delivery system is unlocked to release the distal end of the occluder, and the occluder is gradually released proximally by withdrawing the outer sheath until the proximal compression locking device of the delivery system is finally unlocked, and the delivery system is withdrawn, retaining the guide wire that passes through the hollow channel 10a of the occluder to guide the implantation of a through barrier such as a coated stent 200. The state after implementation can be referred to and combined with Figures 1 and 6.

The above descriptions are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly/indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims (10)

1. An occluder, comprising: A blocking bracket, comprising an inner wall component, an outer wall component and a flow blocker filled between the inner wall component and the outer wall component, wherein the inner wall component is connected to both ends of the outer wall component, the inner wall component surrounds and forms a hollow channel allowing a through-blocker to pass through, and the blocking bracket is in a lantern shape, a column shape or an irregular shape; and Two restraining members are respectively covered on two ends of the blocking stent along the length direction of the hollow channel, and are used to restrain the radial dimension of the hollow channel. 2. The occluder according to claim 1, characterized in that the inner wall member extends in at least one position along the length direction of the hollow channel toward the outer wall member to form a radially extending channel communicating with the hollow channel. 3. The occluder according to claim 2, characterized in that the axial cross-section of the radially extending channel is in the shape of a strip, an arc or a T-shape. 4. The occluder according to claim 1, characterized in that the flow barrier comprises at least one of a fiber membrane, a water-absorbing expandable foam material and a hydrogel material. 5. The occluder according to claim 1, characterized in that the inner wall component and the outer wall component are both composed of a single-layer, double-layer or multi-layer woven mesh, and the material of the woven mesh is at least one of PPDO degradable wire, PLA degradable wire and nickel-titanium alloy wire. The occluder according to claim 1 , wherein the restraining member is a film, a cloth or a wire. 7. The occluder according to claim 6, characterized in that the membrane is at least one of a PPDO film, a PLA film, a PCL film, a PLCL film and a PTFE film; and/or the cloth is an elastic woven cloth woven from PA or PET elastic yarn. 8. The occluder according to claim 6, characterized in that the wire is at least one of PA or PET elastic wire, PPDO degradable wire, PLA degradable wire, PCL degradable wire, and PLCL degradable wire. 9. The occluder according to claim 1, characterized in that the flow blocker and the restraining member both carry the material with antibacterial efficacy by at least one deposition method selected from the group consisting of immersion, co-blending electrospinning, or mixed synthesis. 10. The occluder according to claim 9, characterized in that the material is at least one of triclosan, curcumin, chitosan and tetracycline hydrochloride.