Aneurysm covered stent

Abstract

The invention discloses an aneurysm endo-covered stent, the technical solution of which is as follows: it comprises a plurality of groups of metal rods and biofilms, wherein the plurality of groups of metal rods form a lantern-shaped skeletal stent body, the biofilm covers the outer surface at the middle position of the stent body, the thickness of the biofilm is 8-24 μm, one end of the stent body is connected with a pushing device, the pushing device comprises a guide wire and a delivery catheter sleeved on the guide wire, an opening mechanism is further arranged on the inner side of the biofilm, the opening mechanism is used to open the biofilm so that the biofilm completely blocks the aneurysm neck, the front end of the guide wire is welded to one end of the opening mechanism by hot-melt metal; the blood flow from the tumor-bearing artery to the aneurysm is reduced by the arranged biofilm, and the blood flow impact is reduced; and the invention is arranged between the aneurysm and the tumor-bearing artery to solve the problem of blockage of the side branch blood vessels of the stent segment caused by the conventional covered stent.

Description

Technical Field

[0001] The present invention relates to the technical field of aneurysms, and in particular to an aneurysm endo-covered stent. Background Art

[0002] Aneurysm is a localized or diffuse dilation or bulging of the arterial wall due to lesions or damage to the arterial wall. It is characterized by an expansive, pulsating mass. It can occur in any part of the arterial system, but is more common in the main arteries of the limbs, the aorta, and the carotid arteries.

[0003] At present, the main treatment methods for intracranial aneurysms are surgical clipping of the aneurysm neck and endovascular interventional therapy. The long-term follow-up results of endovascular interventional therapy for intracranial aneurysms show that there is no significant difference in the rebleeding rate compared with clipping surgery, but the re-treatment rate is 7 times that of clipping surgery. Therefore, endovascular interventional treatment of aneurysms is generally better than surgical clipping of the aneurysm neck, so endovascular interventional therapy has gradually become the preferred method for treating aneurysms. The theoretical support of endovascular interventional surgery is to change the hemodynamics in the tumor-bearing artery, achieve vascular reconstruction of the tumor-bearing artery, promote thrombosis in the tumor, and promote endothelialization of the tumor neck, so as to achieve the purpose of curing the aneurysm. The main methods are stent-assisted coil embolization, blood flow guidance device implantation, and covered stent implantation. At present, covered stent implantation has gradually become a new way to treat aneurysms. The existing covered stent includes a support structure and a membrane. The membrane is coated on the outside of the support structure. Through the physical isolation effect of the membrane, the blood flow in the aneurysm lesion site is isolated from the normal circulation, and the blood flow channel is re-established in the tumor-bearing artery. However, this type of covered stent may cause blockage of the side branch vessels in the stent segment or restenosis after stent implantation. Summary of the invention

[0004] In view of the problems mentioned in the background technology, the purpose of the present invention is to provide an aneurysm endovascular stent to solve the problems mentioned in the background technology.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions:

[0006] An aneurysm endo-covered stent comprises a plurality of groups of metal rods and a biomembrane, wherein the plurality of groups of metal rods form a lantern-shaped skeletal stent body, the biomembrane covers the outer surface at the middle position of the stent body, the thickness of the biomembrane is 8-24 μm, one end of the stent body is connected with a pushing device, the pushing device comprises a guide wire and a delivery catheter sleeved on the guide wire, an opening mechanism is further arranged on the inner side of the biomembrane, the opening mechanism is used to open the biomembrane so that the biomembrane completely blocks the aneurysm neck, and the front end of the guide wire is welded to one end of the opening mechanism by heat-melting metal.

[0007] Preferably, the opening mechanism includes an opening plate, an adhesive layer, a push plate, a first hinge block, an opening rod, a second hinge block and a moving block, the opening plate is slidably arranged on the inner side of the biofilm, the adhesive layer is arranged on the outer side of the opening plate, the push plate is arranged on the inner side of the opening plate, the first hinge block is fixedly arranged on the surface of the push plate, the front end of the guide wire is connected to one end of the moving block, the second hinge block is fixedly arranged on the surface of the moving block, and the two ends of the opening rod are respectively hinged to the first hinge block and the second hinge block.

[0008] Preferably, the moving block is arranged at a central position inside the biofilm.

[0009] Preferably, two ends of the stent body are symmetrically provided with first X-ray-opaque marking points, and the number of the first marking points is eight.

[0010] Preferably, two ends of the biofilm are symmetrically provided with second X-ray-opaque marking points, and the number of the second marking points is four.

[0011] Preferably, the method for preparing the stent body comprises the following steps:

[0012] S101. Select a nickel-titanium alloy tube with an outer diameter of 0.60-1.00 mm and a wall thickness of 0.036-0.080 mm, cut it into a mesh shape, the nickel-titanium alloy tube has a filamentous end extending from the distal end, and the proximal opening is an inclined surface, and the process parameters are: current 80-110A, pulse width 3.0-6.0ms, frequency 5-10HZ;

[0013] S102. Expand into a tube with an outer diameter of 2-6 mm. The process parameters are: vacuum degree 10 -3 Pa, heat from room temperature to 400-600℃ in 8-24min, keep warm for 20-40min, cool naturally to room temperature in the furnace to obtain the bracket body.

[0014] Preferably, the method for preparing the biofilm comprises the following steps:

[0015] S201. Decellularizing a mammalian membrane tissue to obtain a decellularized membrane tissue; the decellularized membrane tissue is a double-layer structure having a dense layer and a loose layer;

[0016] S202. Drying the decellularized membrane tissue to volatilize part of the water in the membrane tissue, so that the membrane tissue collapses and shrinks to obtain a shrunk membrane tissue, wherein the moisture content of the shrunk membrane tissue is 20-30%;

[0017] S203. Freeze-dry and sterilize the shrunk membrane tissue to obtain a biofilm.

[0018] Preferably, the mammalian membrane tissue is selected from any one of the small intestinal mucosa, peritoneum, pericardium, amnion or diaphragm; the drying temperature of S202 is 40-60° C., and the drying time is 2-4 hours.

[0019] Preferably, the method for operating the aneurysm stent graft comprises the following steps:

[0020] Step 1: Insert the delivery catheter axially into the aneurysm-bearing artery and push it forward until its front end passes through the aneurysm neck;

[0021] Step 2: Determine the specific position of the stent body by using the development positioning function of the first marking point, and then slowly adjust the stent body according to the position of the second marking point until the biofilm covers the aneurysm neck;

[0022] Step 3: Push the guide wire inwards, so that the guide wire pushes the opening mechanism, so that the moving block pushes the opening plate outwards through the action of the opening rod, contacts and fixes with the adhesive layer, and opens the biofilm, so that the biofilm completely blocks the aneurysm neck;

[0023] Step 4: Keep the guide wire still and remove the delivery catheter;

[0024] Step 5: Connect the electrolytic release device to the end of the guide wire, perform electrofusion release, and remove the guide wire.

[0025] Preferably, the current of the electrolytic release device is 0.4-1 mA, and the time of the electric melting release is 4-8 seconds.

[0026] In summary, the present invention mainly has the following beneficial effects:

[0027] First, the biofilm is set to reduce the blood flow from the parent artery to the aneurysm, reducing blood flow impact, and the present invention is set between the aneurysm and the parent artery to solve the problem of blockage of the side branch blood vessels of the stent segment caused by the previous covered stent;

[0028] Second, the lantern-shaped stent body between the aneurysm and the parent artery uses a biofilm to reduce blood flow and is deployed using the stent, which not only solves the problem of stent blockage but also effectively blocks the aneurysm neck.

[0029] Third, by configuring several groups of metal rods into a lantern-shaped skeletal stent body, rapid deployment of the stent graft can be achieved, while also preventing blockage of side branch vessels of the stent graft segment, reducing blood flow from the parent artery to the aneurysm, and reducing blood flow impact. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is one of the structural schematic diagrams of the present invention;

[0031] Figure 2 It is the second structural cross-sectional view of the present invention.

[0032] Figure numerals: 1. metal rod; 2. biomembrane; 3. stent body; 4. guide wire; 5. delivery catheter; 6. aneurysm neck; 7. opening plate; 8. bonding layer; 9. push plate; 10. first hinge block; 11. opening rod; 12. second hinge block; 13. moving block; 14. first marking point; 15. second marking point; 16. tumor-bearing artery. DETAILED DESCRIPTION

[0033] 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.

[0034] Example 1

[0035] refer to Figure 1-2 , an aneurysm endo-covered stent, comprising a plurality of groups of metal rods 1 and a biomembrane 2, wherein the plurality of groups of the metal rods 1 form a lantern-shaped skeletal stent body 3, wherein the biomembrane 2 covers the outer surface of the middle position of the stent body 3, wherein the thickness of the biomembrane 2 is 8 μm, and a pushing device is connected to one end of the stent body 3, wherein the pushing device comprises a guide wire 4 and a delivery catheter 5 sleeved on the guide wire 4, and an opening mechanism is further arranged on the inner side of the biomembrane 2, wherein the opening mechanism is used to open the biomembrane 2 so that the biomembrane 2 completely blocks the aneurysm neck 6, and the front end of the guide wire 4 is welded to one end of the opening mechanism by heat-melting metal.

[0036] refer to Figure 2 The opening mechanism includes an opening plate 7, an adhesive layer 8, a push plate 9, a first hinge block 10, an opening rod 11, a second hinge block 12 and a moving block 13. The opening plate 7 is slidably arranged on the inner side of the biomembrane 2, the adhesive layer 8 is arranged on the outer side of the opening plate 7, the push plate 9 is arranged on the inner side of the opening plate 7, the first hinge block 10 is fixedly arranged on the surface of the push plate 9, the front end of the guide wire 4 is connected to one end of the moving block 13, the second hinge block 12 is fixedly arranged on the surface of the moving block 13, and the two ends of the opening rod 11 are respectively hinged to the first hinge block 10 and the second hinge block 12; by pushing the guide wire 4 inward, the guide wire 4 pushes the opening mechanism, so that the moving block 13 pushes the opening plate 7 to open outward through the action of the opening rod 11, contacts and fixes with the adhesive layer 8, opens the biomembrane 2, and makes the biomembrane 2 completely block the aneurysm neck 6.

[0037] refer to Figure 2In order to facilitate force balance and push the moving block 13 , the moving block 13 is arranged at the center position of the inner side of the biofilm 2 .

[0038] refer to Figure 1 , in order to facilitate positioning; the two ends of the stent body 3 are symmetrically provided with first X-ray-proof marking points 14, and the number of the first marking points 14 is eight.

[0039] refer to Figure 1 , in order to facilitate positioning; the two ends of the biofilm 2 are symmetrically provided with second X-ray-proof marking points 15, and the number of the second marking points 15 is four.

[0040] In this embodiment, the method for preparing the support body 3 comprises the following steps:

[0041] S101. Select a nickel-titanium alloy tube with an outer diameter of 0.60 mm and a wall thickness of 0.036 mm, cut it into a mesh shape, the nickel-titanium alloy tube has a filamentous end extending from the distal end, and the proximal opening is an inclined surface, and the process parameters are: current 80-110A, pulse width 3.0ms, frequency 5HZ;

[0042] S102. Expand into a tube with an outer diameter of 2 mm. The process parameters are: vacuum degree 10 -3 Pa, raise the temperature from room temperature to 400°C in 8 minutes, keep it at that temperature for 20 minutes, and naturally cool it to room temperature in the furnace to obtain the bracket body 3.

[0043] In this embodiment, the method for preparing the biofilm 2 comprises the following steps:

[0044] S201. Decellularizing a mammalian membrane tissue to obtain a decellularized membrane tissue; the decellularized membrane tissue is a double-layer structure having a dense layer and a loose layer;

[0045] S202. Drying the decellularized membrane tissue to volatilize part of the water in the membrane tissue, so that the membrane tissue collapses and shrinks to obtain a shrunk membrane tissue, wherein the moisture content of the shrunk membrane tissue is 20%;

[0046] S203. Freeze-dry and sterilize the shrunk membrane tissue to obtain biofilm 2.

[0047] In this embodiment, the mammalian membrane tissue is selected from the small intestinal mucosa; the drying temperature of S202 is 40° C., and the drying time is 4 hours.

[0048] In this embodiment, the method for operating the aneurysm stent graft comprises the following steps:

[0049] Step 1: Extend the delivery catheter 5 axially into the aneurysm-bearing artery 16 and push it forward until its front end passes through the aneurysm neck 6;

[0050] Step 2: Determine the specific position of the stent body 3 by using the development positioning function of the first marking point 14, and then slowly adjust the stent body 3 according to the position of the second marking point 15 until the biofilm 2 covers the aneurysm neck 6;

[0051] Step 3: Push the guide wire 4 inwards, so that the guide wire 4 pushes the opening mechanism, so that the moving block 13, through the action of the opening rod 11, pushes the opening plate 7 to open outwards, contacts and fixes with the adhesive layer 8, and opens the biofilm 2, so that the biofilm 2 completely blocks the aneurysm neck 6;

[0052] Step 4: Keep the guide wire 4 still and remove the delivery catheter 5;

[0053] Step 5: Connect the electrolytic release device to the end of the guide wire 4, perform electrofusion release, and remove the guide wire 4.

[0054] In this embodiment, the current of the electrolytic release device is 0.4 mA, and the time of the electric melting release is 4 seconds.

[0055] Example 2

[0056] The difference from Example 1 is that the preparation method of the stent body 3 comprises the following steps:

[0057] S101. Select a nickel-titanium alloy tube with an outer diameter of 1.00 mm and a wall thickness of 0.080 mm, cut it into a mesh shape, the distal end of the nickel-titanium alloy tube has a filamentary end extending out, and the proximal opening is an inclined surface, and the process parameters are: current 110A, pulse width 6.0ms, frequency 10HZ;

[0058] S102. Expand into a tube with an outer diameter of 6 mm. The process parameters are: vacuum degree 10 -3 Pa, the temperature was raised from room temperature to 600°C in 24 min, kept at that temperature for 40 min, and naturally cooled to room temperature in the furnace to obtain the bracket body 3.

[0059] In this embodiment, the method for preparing the biofilm 2 comprises the following steps:

[0060] S201. Decellularizing a mammalian membrane tissue to obtain a decellularized membrane tissue; the decellularized membrane tissue is a double-layer structure having a dense layer and a loose layer;

[0061] S202. Drying the decellularized membrane tissue to volatilize part of the water in the membrane tissue, so that the membrane tissue collapses and shrinks to obtain a shrunk membrane tissue, wherein the moisture content of the shrunk membrane tissue is 30%;

[0062] S203. Freeze-dry and sterilize the shrunk membrane tissue to obtain biofilm 2.

[0063] In this embodiment, the mammalian membrane tissue is selected from peritoneum; the drying temperature of S202 is 60° C., and the drying time is 2 hours.

[0064] In this embodiment, the method for operating the aneurysm stent graft comprises the following steps:

[0065] Step 1: Extend the delivery catheter 5 axially into the aneurysm-bearing artery 16 and push it forward until its front end passes through the aneurysm neck 6;

[0066] Step 2: Determine the specific position of the stent body 3 by using the development positioning function of the first marking point 14, and then slowly adjust the stent body 3 according to the position of the second marking point 15 until the biofilm 2 covers the aneurysm neck 6;

[0067] Step 3: Push the guide wire 4 inwards, so that the guide wire 4 pushes the opening mechanism, so that the moving block 13, through the action of the opening rod 11, pushes the opening plate 7 to open outwards, contacts and fixes with the adhesive layer 8, and opens the biofilm 2, so that the biofilm 2 completely blocks the aneurysm neck 6;

[0068] Step 4: Keep the guide wire 4 still and remove the delivery catheter 5;

[0069] Step 5: Connect the electrolytic release device to the end of the guide wire 4, perform electrofusion release, and remove the guide wire 4.

[0070] In this embodiment, the current of the electrolytic release device is 1 mA, and the time of the electric melting release is 8 seconds.

[0071] Principle and advantages of use:

[0072] First, the biological membrane 2 is provided to reduce the blood flow from the parent artery 16 to the aneurysm, thereby reducing the blood flow impact. Moreover, the biological membrane 2 is provided between the aneurysm and the parent artery 6 to solve the problem of blockage of the side branch vessels of the stent segment caused by the conventional covered stent.

[0073] Second, the lantern-shaped stent body 3 between the aneurysm and the parent artery 6 uses the biofilm 2 to reduce blood flow and uses the stent to achieve deployment, thereby solving the problem of stent blockage and effectively blocking the aneurysm neck 6;

[0074] Third, by configuring several groups of metal rods 1 into a lantern-shaped skeleton stent body 3, rapid deployment of the stent graft can be achieved, while also preventing blockage of side branch vessels of the stent graft segment, reducing blood flow from the parent artery 16 into the aneurysm, and reducing blood flow shock.

[0075] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An aneurysm stent graft, characterized in that: The invention comprises a plurality of groups of metal rods (1) and biofilms (2), wherein the plurality of groups of metal rods (1) form a lantern-shaped skeletal stent body (3), wherein the biofilm (2) covers the outer surface of the middle position of the stent body (3), wherein the thickness of the biofilm (2) is 8-24 μm, wherein one end of the stent body (3) is connected with a pushing device, wherein the pushing device comprises a guide wire (4) and a delivery catheter (5) sleeved on the guide wire (4), wherein an opening mechanism is further arranged on the inner side of the biofilm (2), wherein the opening mechanism is used to open the biofilm (2) so that the biofilm (2) completely blocks the aneurysm neck (6), and wherein the front end of the guide wire (4) is welded to one end of the opening mechanism by heat-melting metal. The opening mechanism comprises an opening plate (7), an adhesive layer (8), a push plate (9), a first hinge block (10), an opening rod (11), a second hinge block (12) and a moving block (13); the opening plate (7) is slidably arranged on the inner side of the biofilm (2); the adhesive layer (8) is arranged on the outer side of the opening plate (7); the push plate (9) is arranged on the inner side of the opening plate (7); the first hinge block (10) is fixedly arranged on the surface of the push plate (9); the front end of the guide wire (4) is connected to one end of the moving block (13); the second hinge block (12) is fixedly arranged on the surface of the moving block (13); and the two ends of the opening rod (11) are respectively hinged to the first hinge block (10) and the second hinge block (12).

2. The aneurysm stent graft according to claim 1, characterized in that: The moving block (13) is arranged at the center position inside the biofilm (2).

3. The aneurysm stent graft according to claim 1, characterized in that: Two ends of the stent body (3) are symmetrically provided with first marking points (14) that are not transparent to X-rays, and the number of the first marking points (14) is eight.

4. The aneurysm stent graft according to claim 1, characterized in that: X-ray-proof second marking points (15) are symmetrically arranged at both ends of the biofilm (2), and the number of the second marking points (15) is four.

5. The aneurysm stent graft according to claim 1, characterized in that: The method for preparing the stent body (3) comprises the following steps: S101. Select a nickel-titanium alloy tube with an outer diameter of 0.60-1.00 mm and a wall thickness of 0.036-0.080 mm, cut it into a mesh shape, the nickel-titanium alloy tube has a filamentous end extending from the distal end, and the proximal opening is an inclined surface, and the process parameters are: current 80-110A, pulse width 3.0-6.0ms, frequency 5-10HZ; S102. Expand into a tube with an outer diameter of 2-6 mm. The process parameters are: vacuum degree 10 -3 Pa, heating from room temperature to 400-600°C in 8-24 minutes, keeping the temperature for 20-40 minutes, and naturally cooling to room temperature in the furnace to obtain the bracket body (3).

6. The aneurysm stent graft according to claim 1, characterized in that: The method for preparing the biofilm (2) comprises the following steps: S201. Decellularizing a mammalian membrane tissue to obtain a decellularized membrane tissue; the decellularized membrane tissue is a double-layer structure having a dense layer and a loose layer; S202. Drying the decellularized membrane tissue to volatilize part of the water in the membrane tissue, so that the membrane tissue collapses and shrinks to obtain a shrunk membrane tissue, wherein the moisture content of the shrunk membrane tissue is 20-30%; S203. Freeze-dry and sterilize the shrunk membrane tissue to obtain a biofilm (2).

7. The aneurysm stent graft according to claim 6, characterized in that: The mammalian membrane tissue is selected from any one of small intestinal mucosa, peritoneum, pericardium, amnion or diaphragm; the drying temperature of S202 is 40-60° C., and the drying time is 2-4 hours.

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