CN115153949A

CN115153949A - Far-end embolism protection device and manufacturing method thereof

Info

Publication number: CN115153949A
Application number: CN202210847312.0A
Authority: CN
Inventors: 赵振心; 侯可顺; 成立萍; 朱佳英
Original assignee: Skynor Medical Technology Shanghai Co ltd
Current assignee: Skynor Medical Technology Shanghai Co ltd
Priority date: 2022-07-19
Filing date: 2022-07-19
Publication date: 2022-10-11
Anticipated expiration: 2042-07-19
Also published as: CN115153949B

Abstract

The invention discloses a far-end embolic protection device, which comprises a pushing guide wire, a filter screen and an outer sheath tube, wherein the filter screen is of a cone-like structure with an opening at the near end, and the far end and the near end of the filter screen are fixed by a fixing ring; the filter screen is provided with a support ring. The distal end embolism protection device is conveyed into a diseased vessel through a catheter and is used in nerve and peripheral intervention operations, and the device provides high radial force to be supported in the vessel wall after being opened, so that the maximum opening degree of a collecting opening is always kept. Avoiding the displacement of the distal protection device in the blood vessel during the subsequent delivery or release of the therapeutic device. The aperture of the mesh of the filter screen is reduced, so that embolic particles falling off in the operation can be effectively intercepted and collected, and the vascular complications caused by the fact that the embolus enters and blocks the downstream blood vessel along with the blood flow can be prevented.

Description

Far-end embolism protection device and manufacturing method thereof

Technical Field

The invention relates to the technical field of medical instruments, in particular to a distal embolic protection device and a manufacturing method thereof.

Background

Some procedures involving interventional cerebral and lower extremity arteries, etc., involve the formation of platelet polymers (e.g., emboli, lipid droplets, bacterial clots and/or other foreign matter, tumor cells or other small tissue fragments) or atheromatous debris and debris from the arterial wall broken down by the surgical instruments during the procedure, which are transported through the bloodstream and enter the cerebral blood circulation and other important systemic arterial systems as embolized vascular material. Embolic material entering cerebral blood circulation can block arterioles, thereby causing local cerebral vascular embolism to occur, and the cerebral vascular embolism becomes an important complication of ischemic brain diseases at present. Substances entering the blood circulation of the lower limb can cause embolism of blood vessels below the knee, and the embolism of the blood vessels below the knee can cause dysfunction of activities or necrosis of foot tissues.

Generally, to prevent complications from embolic particles, it is often necessary to capture or collect forward flowing plaque, debris, or emboli with a distal protective device during the procedure to prevent the formation of an embolism. However, the conventional distal protection system is interfered by a subsequent treatment instrument in the using process, so that poor adherence is easy to occur, and the distal protection device is displaced, so that the probability of embolus escape is high.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a distal embolic protection device and a manufacturing method thereof, wherein the distal embolic protection device is delivered into a diseased vessel through a catheter. The device is used in nerve and peripheral intervention operation, provides high radial force to support in a vessel wall after being opened, and always keeps the maximum opening degree of a collecting opening. Avoiding the displacement of the distal protection device in the blood vessel during the subsequent delivery or release of the therapeutic device. The aperture of the mesh of the filter screen is reduced, so that embolic particles falling off in the operation can be effectively intercepted and collected, and the vascular complications caused by the fact that the embolus enters and blocks the downstream blood vessel along with the blood flow can be prevented.

In order to achieve the purpose, the invention provides a far-end embolic protection device and a manufacturing method thereof. The filter screen is arranged in the propelling movement seal wire distal end, is equipped with stop device in the middle of filter screen and the propelling movement seal wire, the propelling movement seal wire is worn in a sheath pipe together with the filter screen. Distal end embolism protection device including propelling movement seal wire 10, filter screen 20, outer sheath pipe 60, the filter screen be near-end open-ended class conical structure, the filter screen far-end near-end fixed by solid fixed ring 40, the filter screen on contain support ring 30, propelling movement seal wire and filter screen between be equipped with stop device 50, the support ring on contain anti breaking stress diffusion structure 31, solid fixed ring be hollow structure.

Furthermore, the filter screen is formed by weaving one or more of round wires, flat wires and spiral wires;

furthermore, the mixed weaving mode of the filter screen is that two round wires and one flat wire are added; the whole filter screen is in a cone-like shape with an opening at the near end; the filter screen is made of one or more of stainless steel, nickel-titanium alloy, cobalt-chromium alloy, polyurethane, nylon, terylene and polyether block amide;

further, the aperture of the filter screen is gradually enlarged from the far end to the near end mesh;

furthermore, the limiting device is of a spiral structure and is made of developing materials;

furthermore, the limiting device is cut into a spiral shape in a tubular shape and can also be formed by winding silk threads;

further, the number of the support rings is not less than 1; the support rings are arranged along the axial direction of the push guide wire; the support rings which are arranged axially are wound on the filter screen;

furthermore, a support ring matched with the shape of the opening at the near end of the filter screen is wound at the opening of the near end of the filter screen;

further, the support ring is made of silk or made by laser cutting;

further, the support ring is one of a circular, oval and unclosed annular structure; the supporting ring can be made of developing materials or developing materials added on the supporting ring;

furthermore, the anti-bending stress diffusion structure is arranged on one or more of a spiral line type structure, an omega type structure, a convex type structure and a concave type structure on the support ring;

further, the support ring is provided with the anti-bending stress diffusion structure and is subjected to heat treatment setting, and the shape of the support ring is subjected to heat treatment or not;

further, the opening part is connected with the opening of the near end of the filter screen in a winding way to form a whole;

furthermore, the spiral limiting device is integrally sleeved between the filter screen and the pushing rod, and can also be flexibly connected with the far end of the pushing guide wire and the near end of the pushing guide wire through a spring;

furthermore, fixing rings at two ends of the conical filter screen are of a hollow structure, so that the filter screen can integrally slide on the pushing guide wire; the fixing ring is made of developing materials;

further, the manufacturing method of the anti-bending stress diffusion structure of the support ring comprises the following steps: the anti-bending stress diffusion structure is manufactured by heat treatment after passing through a forming die; the forming die is provided with a forming structure positioning column.

Compared with the prior art, the invention has the following beneficial effects:

the invention provides a distal protection device and a manufacturing method thereof, wherein the distal protection device comprises a filter screen and a push guide wire which are connected together, and a cone-like proximal opening type filter screen structure can provide a more stable sheath tube which can be compressed to a smaller diameter. When in operation, the sheath tube with the embolism protection device is implanted into a human blood vessel and pushed to the distal end of a stenotic lesion, and the filter screen is released by withdrawing the sheath tube. The filter screen struts the opening at the near end of the filter screen under the action of the support ring, clings to the inner wall of the blood vessel and plays a role in collecting emboli dropped from the blood vessel.

Wherein the mixed woven filter screen of the round filaments and the flat filaments 2+1 effectively reduces the aperture of the meshes and improves the capability of intercepting emboli.

Wherein the opening at the near end of the filter screen is provided with a supporting structure for helping the filter screen to be opened; the support ring is configured to provide a radial force between the screen proximal opening and the vessel wall in the open state. Thereby improving the adherence performance of the filter screen and the blood vessel and preventing the device from shifting caused by the interference of subsequent treatment instruments in the using process.

The support ring of the present invention also achieves an anti-buckling effect. When the filter screen is compressed into the small-diameter sheath tube (2-3F) and is subjected to material limit deformation, the original set size capability is recovered again, and the protection device after shrinkage loses the original natural diameter. The antiflex structure is capable of resisting material damage caused by extreme deformation.

The spiral limiting structure can reduce the risk of displacement of the protective umbrella caused by subsequent conveying or withdrawing of the therapeutic apparatus.

Drawings

The features and advantages of the present invention will become apparent from the following detailed description of the embodiments of the invention, which proceeds with reference to the accompanying drawings.

FIG. 1 shows a schematic view of the deployment of an embolic protection device with a reinforcing support ring of the present invention;

FIG. 2-1 shows a schematic of the screen construction of the present invention;

FIG. 2-2 is a schematic diagram illustrating the manner in which the filter screen of the present invention is woven;

FIG. 3-1 shows a schematic view of the support ring structure of the present invention;

FIG. 3-2 shows a schematic view of the structure of the invention for resisting the spreading of flexural stresses on the support ring;

FIGS. 3-3 show a schematic view of a plurality of flexural stress diffusion resistant structures of the present invention on a support ring;

FIG. 4 is a schematic view of the support ring of the present invention mounted to the periphery of the proximal end opening of the filter screen;

FIG. 5 is a schematic view of the proximal end of the support ring and the screen secured within the retaining ring of the present invention;

FIG. 6 is a schematic view of another open-loop support ring structure according to the present invention;

FIG. 7 shows the mounting and pushing of the retaining rings at the two ends of the screen of the present invention onto a guidewire;

FIG. 8 is a schematic view of the filter screen, push wire, and retainer assembly of the present invention;

FIG. 9 shows a mold for manufacturing a bending stress diffusion resistance structure according to the present invention;

fig. 10 shows a support ring forming mold of the present invention.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In describing the embodiments of the present invention in detail, the drawings are not necessarily to scale, and the drawings are not intended to limit the invention.

In the invention referred to in the patent of the invention, the "proximal end" refers to the end close to the doctor performing the operation, and the "distal end" refers to the end far from the doctor performing the operation.

Fig. 1 shows a schematic deployment view of a distal protection device with a reinforced support ring according to the present invention, which comprises a push wire 10, a filter mesh 20, a support ring 30, a filter mesh distal and proximal fixation ring 40, a helical stop 50, and an outer sheath 60. The far-end protection device penetrates through the push guide wire, the far end of the push guide wire is provided with a developing section 11, and the far-end and near-end fixing rings of the far-end protection device are developing points. The spiral limiting device is installed between the pushing guide wire and the filter screen.

When the device is used, the push guide wire far-end protection device is firstly withdrawn, can smoothly enter the outer sheath tube, and then is integrally conveyed to the far-end part of the diseased blood vessel, and the outer sheath tube is withdrawn to release the far-end protection device.

Fig. 2-1 shows a schematic structural diagram of a filter screen according to the present invention, wherein the filter screen is formed by interlacing and weaving a plurality of shape memory materials, which can be made of a nickel-titanium material, a cobalt-chromium alloy or a polymer material with shape memory. The number of the braided wires is determined by the final natural molding diameter of the filter screen, and 32, 48, 64, 72 and 96 wires 21 can be selected. The knitting can be selected from the modes of 1+1 (1 up and 1 down), 2+1 (2 up and 1 down) and 2+2 (2 up and 2 down), and the filter screen in the invention is knitted by 2+1 (figure 2-2), namely the knitting mode of 2 round wires 210 and 1 flat wire 211. The method effectively reduces the aperture of the meshes and considers the characteristics of structural stability and easy compression. The filter screen is of a cone-like near-end opening type, the knitting yarns are uniformly knitted on a cylindrical die in a fixed mode, then the knitting yarns are replaced on the conical die, and the filter screen is formed by closing the far end and expanding the near end for heat setting. When the blood vessel is manufactured, the diameter of the opening at the near end is slightly larger than that of a target blood vessel, and the opening is a longitudinal section of a beveled blood vessel, so that the contact surface is enlarged, and all forward blood flows can be ensured to pass through the opening. The distal end closes up to form a collecting net bag, and the mesh holes of the conical filter net are gradually changed from big mesh holes at the proximal end 23 to small mesh holes at the distal end 22. The aperture range of the filter screen is 350um-50um. The structure can capture and collect the fallen thrombus to the maximum extent.

Fig. 3-1 shows a schematic view of the structure of the support ring of the present invention, the shape of the support ring is matched with the shape of the opening at the proximal end of the filter screen, and the support ring can be circular, oval, or unclosed ring. The anti stress diffusion structure of rolling over that is provided with on the support ring increases and transversely opens the dynamics, supports whole filter screen opening, guarantees filter screen and blood vessel joint strength. The filter screen is helped to be fixed in the far-end blood vessel, and the far-end protective device is not displaced or dropped due to the interference of the delivery and the release of the subsequent therapeutic device.

At the same time, the support rings may be arranged in a plurality of axial directions along the push rod (fig. 2-1), thereby ensuring that more thrombus can be captured or accommodated.

The rupture stress spreading structure 31 on the support ring may be a spiral, omega-shaped, concave or convex structure (fig. 3-2). Preferably, the spiral structure is similar to a daily spring component, and can store stronger elastic force and prevent the filter screen from being restored to a natural initial state between compression and expansion due to plastic deformation of the material. The entire distal protection device needs to work within a sheath that is compressed to a minimum. The compression ratio is 4-8 times, and the natural form of the filter screen is greatly tested, so that the invention is specially designed on the support ring.

The support ring is made of a shape memory material, or can be made by twisting a plurality of wires into a strand. Can also be produced in the form of laser cutting from corresponding tubes or sheets. The invention is preferably made of a single nitinol wire. The anti-bending stress diffusion structure is arranged at the top end of the support ring component, and can also be arranged around the support ring, and the number of the anti-bending stress diffusion structure is 1-3 (figures 3-3). The support ring can be a complete circle or a semi-open circular arc. In the embodiment, the anti-bending stress diffusion structure is arranged at the top end of the support ring, and the other end of the support ring is converged into two end points which are pressed and held in the fixing ring at the proximal end of the filter screen. In order to maximize the function of the anti-bending stress diffusion structure, the anti-bending stress diffusion structure on the support ring needs to be shaped by heat treatment setting in the manufacturing process, and the shape of the support ring is shaped by heat treatment or not. The invention is preferably a support ring which is not shaped by heat treatment, and the support ring is hooped into a similar circular ring shape by utilizing the elasticity of the nickel-titanium alloy in a linear state, so that the stress diffusion is further increased, the supporting force is more effectively increased, and the filter screen is ensured not to be influenced by subsequent treatment instruments to displace.

FIG. 4 the support ring of the present invention is integrally attached to the periphery 24 of the proximal end opening of the screen in a wound manner and secured within the proximal end retainer ring of the screen (FIG. 5). The mode can ensure the synchronization performance of the support ring and the opening at the near end of the filter screen, and prevent the filter screen from being asynchronous when being compressed into the outer sheath tube. Fig. 6 shows another way of installing an open loop support ring by forming hangers at both ends of the support ring to hang over the openings at the proximal end of the screen. And also for the purposes of fixing and synchronizing.

In order to judge that the support ring is coated with the developing material from the compressed state to the opened adherence state in the using process, the invention adopts the form of winding the developing wire on the support ring. The development performance can also be realized by the hollow form of the nickel-titanium material which is internally provided with the development material.

FIG. 7 shows that the hollow retainer rings at both ends of the filter screen facilitate the overall sliding of the filter screen over the push guidewire. The filter screen is wrapped by two metal material pipes to form a sandwich structure, and the three are welded into a whole by using a laser welding technology. The support rings are also secured together within the proximal end retainer ring. The fixed ring is divided into an outer ring 41 and an inner ring 42, and both rings may select the same developing material or only one ring may select the developing material. The two-end visualization can accurately judge the position of the far-end protection device in the far-end blood vessel.

Fig. 8 shows an installation diagram of a filter screen, a push guide wire and a stopper according to the present invention, wherein the filter screen is installed on the push guide wire, the stopper is fixed between the filter screen and the push guide wire, and the stopper serves to limit the lateral displacement of the filter screen and also enables the filter screen to integrally slide on the push guide wire. The stopper can realize the recovery and the release function of filter screen. The filter screen is relatively kept to be independently supported in a target blood vessel, and the subsequent therapeutic instruments are conveyed in place by pushing the guide wire, so that the filter screen is kept independent, and better embolus can be captured and collected.

Fig. 7 shows a schematic view of the spacing device, which is cut in a tubular shape into a spiral shape 51, and is also a developing material. When in use, the distal protection device is required to be conveyed in a tortuous blood vessel, so that the spiral shape plays a role in flexibility and is convenient to convey in place. In another embodiment of fig. 8, the stop device can be made of a coil spring 52, the push guide wire is split, the stop device is connected with the distal end 101 and the proximal end 102 of the push guide wire, and the middle of the stop device is suspended, so that the risk of puncture of a blood vessel due to the movement of the distal end of the push guide wire when a subsequent therapeutic device is conveyed can be reduced.

The manufacturing method of the support ring structure of the invention is that,

wherein, the preparation of the support ring comprises the following steps:

a nickel-titanium alloy wire with the wire diameter of 0.15-0.05mm is selected to be wound into a spiral anti-bending stress diffusion structure along a positioning rod 70 above a die, the wire material is straightened and fixed on fixing pieces 71 at two ends, and the wire material can be directly used as a support ring part to be installed at the opening of the near end of the filter screen after heat treatment, shaping and cutting (figure 9).

Or fixing the nickel-titanium wire with the anti-bending stress diffusion structure on the filter screen opening forming die again for the second heat treatment 72 to ensure that the shape of the support ring structure is the same as that of the filter screen opening, thereby achieving the same matching purpose (figure 10).

The embolic protection device of the present invention, in the proper size, may also be suitable for other intravascular treatments. Those skilled in the art will appreciate that the foregoing description is by way of example only. That is, all equivalent changes and modifications made according to the content of the claims of the present invention should be considered as the technical scope of the present invention.

Claims

1. A distal embolic protection device comprises a propelling guide wire (10), a filter screen (20) and an outer sheath tube (60), wherein the filter screen is of a cone-like structure with an opening at the proximal end, and the distal end and the proximal end of the filter screen are fixed by a fixing ring (40); the method is characterized in that: the filter screen on contain support ring (30), propelling movement seal wire and filter screen between be equipped with stop device (50), the support ring on contain anti breaking stress diffusion structure (31), solid fixed ring be hollow structure.

2. The distal embolic protection device of claim 1, wherein the screen is woven from one or more of round, flat, and spiral filaments.

3. The distal embolic protection device of claim 1, wherein the filter mesh is made of one or more of stainless steel, nitinol, cobalt-chromium alloy, polyurethane, nylon, polyester, and polyether block amide.

4. The distal embolic protection device of claim 1, wherein the mesh size increases from the distal to the proximal mesh.

5. The distal embolic protection device of claim 1, wherein the stop device is a helical structure.

6. The distal embolic protection device of claim 1, wherein the retention means is comprised of a contrast material.

7. The distal embolic protection device of claim 1, wherein the number of support rings is not less than 1.

8. A distal embolic protection device as in claims 1 and 7, wherein the proximal opening of the filter mesh is wrapped with a support ring conforming to its shape.

9. A distal embolic protection device as in claims 1 and 7, wherein the support ring of the filter mesh is axially aligned on the filter mesh along the pusher wire.

10. The distal embolic protection device of claim 1, wherein the support ring is one of circular, oval, or non-enclosed annular in configuration.

11. The distal embolic protection device of claim 1, wherein the support ring comprises a developable material.

12. The distal embolic protection device of claim 1, wherein the rupture stress spreading resistance structure is one or more of a helical structure, an omega-shaped, a convex and a concave structure disposed on the support ring.

13. The method of making a distal embolic protection device of claim 1, wherein: the anti-bending stress diffusion structure of the support ring comprises: the anti-bending stress diffusion structure is manufactured by heat treatment after passing through a forming die; the forming die is provided with a forming structure positioning column.