Balloon-expandable covered stent for arterial occlusion

Abstract

The present invention discloses a balloon-expandable covered stent for arterial occlusion, belonging to the field of medical devices, which includes: a main channel, a first branch and a second branch, the first branch and the second branch are both connected to the same end of the main channel; a balloon, which is sleeved on the stent structure in a bent state, including a first section and a second section, the first section is sleeved on the first branch, the second section is sleeved on the second branch, and the first section and the second section are connected in the main channel. Through the above-mentioned arrangement, the present invention can accurately position the expansion and release in the patient's body, and has extremely high feasibility; after release, the lumen can be regained to avoid thrombus or plaque detachment and embolism; and it can be used for stenosis and occlusion lesions of the starting segments of the abdominal aorta and iliac arteries, and to reconstruct the distal bifurcation morphology of the abdominal aorta to make it more consistent with the original morphology of the aorta and iliac arteries, reduce complications, and reduce the difficulty of later treatment.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and in particular relates to a balloon-expandable covered stent for arterial occlusion. Background Art

[0002] Currently, people's work and rest and eating habits are constantly changing with the accelerated pace of life, which leads to a slowdown in the body's metabolism and blood circulation, and in turn makes the incidence of vascular diseases increasingly higher. Such diseases can cause consequences such as organ lesions. If not treated in time, they will pose a huge risk to life safety.

[0003] Vascular stents are often used in the treatment of vascular diseases. By sending the vascular stent into the occluded section of the blood vessel and expanding it after positioning, the blood flow in the blood vessel is restored. Vascular stent implantation surgery has the characteristics of high success rate, small incision, and long effective time. It is an effective means of vascular dilation. The vascular stents currently used in clinical practice mainly include two types according to the release method: self-expanding stents that expand by themselves after the fixation is released in the blood vessel, and balloon-expandable stents that expand by balloon expansion in the blood vessel. The stents used for peripheral arteries are mostly self-expanding stents, and balloon-expandable stents are often used for lesions at the arterial opening and are not easily compressed by external forces. Currently, most vascular stents used to solve arterial occlusions use self-expanding stents, which have the defect of relative displacement with the blood vessel during expansion, resulting in inaccurate positioning. The abdominal aorta is divided into two iliac arteries at the distal end. The bifurcation is a high-incidence area of ​​arterial stenosis and occlusion. Because the abdominal aorta is divided into two here, the requirements for the stent are relatively high. The commonly used technology is the kissing technique, that is, stents are implanted in both iliac arteries at the same time, and the stents are extended to the same height of the abdominal aorta. This technology does not reconstruct the bifurcation morphology of the abdominal aorta. The residual lumen after surgery is prone to thrombosis, and the positioning is inaccurate, making further intervention difficult.

[0004] Therefore, it is necessary to design a balloon-expandable vascular stent that can ensure accurate positioning and reconstruct the morphology of the abdominal aorta, specifically a balloon-expandable covered stent for arterial occlusion. Summary of the invention

[0005] In order to overcome the problems raised in the background technology, the present invention adopts the following technical solutions:

[0006] A balloon-expandable covered stent for arterial occlusion, comprising: a stent structure, comprising a main channel, a first branch and a second branch, the first branch and the second branch are both connected to the same end of the main channel, the axis of the first branch is parallel to the axis of the second branch, and the axis of the first branch is parallel to the axis of the main channel; a balloon, which is sleeved on the stent structure in an empty state, comprising a first section and a second section, the first section is sleeved on the first branch, the second section is sleeved on the second branch, and the first section and the second section are connected in the main channel.

[0007] Furthermore, the main channel, the first branch and the second branch are all mesh structures, and the mesh structure is lined with a coating layer.

[0008] Furthermore, in the axial direction of the main channel, the length of the mesh structure is equal to the length of the coating layer; in the axial direction of the first branch, the length of the mesh structure is equal to the length of the coating layer; in the axial direction of the second branch, the length of the mesh structure is equal to the length of the coating layer. There are marks on the first branch and the second branch for connecting other brackets and marking the starting positions of the first branch and the second branch.

[0009] Furthermore, the material of the coating layer is expanded polytetrafluoroethylene.

[0010] Furthermore, the mesh structure is made of a material selected from the group consisting of nickel-titanium alloy and cobalt-chromium alloy.

[0011] Furthermore, the length and diameter of the first branch are the same as those of the second branch.

[0012] Furthermore, the diameter of the main channel ranges from 12 mm to 30 mm, and the total length of the support structure in the axial direction of the main channel is at least 35 mm.

[0013] Furthermore, the diameter of the first branch is in the range of 6 mm to 12 mm, the diameter of the second branch is the same as the diameter of the first branch, the axial length of the first branch is at least 13 mm, and the axial length of the second branch is the same as the first branch.

[0014] Furthermore, the balloon has an initial state after expansion, and in the initial state, the first section and the second section have the same length.

[0015] Furthermore, a filling cavity and a delivery rod are provided in the balloon, a guide wire cavity is provided in the delivery rod, the delivery rod is arranged through the first section, one end of the delivery rod is arranged to pass through the outside of the first section, and the other end of the delivery rod is retained outside the patient's body through the blood vessel.

[0016] Furthermore, a traction guide wire is connected to the balloon, one end of which is connected to the inner wall of the second section, and the other end of the traction guide wire penetrates into the stent structure from the second branch and exits from the first branch. The other end of the traction guide wire extends out of the patient's body along the delivery rod. In the empty state, the delivery rod is pushed toward the abdominal aorta to separate the balloon and the stent structure in the axial direction of the main channel, and then the traction guide wire is pulled to make the second section stick to the first section, and finally the balloon is withdrawn from the patient's body through the first branch.

[0017] Alternatively, after the stent is deployed and positioned, the balloon is emptied and the delivery rod is pushed toward the abdominal aorta so that both the first section and the second section enter the main channel, and then the delivery rod is pulled outward along the insertion path so that the balloon is pulled out of the body.

[0018] Furthermore, the support structure also includes a developing mark point, and the developing mark point is connected to the outer wall of the support structure.

[0019] Furthermore, two developing marking points are arranged in an array on the outer walls at both ends of the main channel, one developing marking point is arranged on the outer wall of the end of the first branch that is not connected to the main channel, and one developing marking point is arranged on the outer wall of the end of the second branch that is not connected to the main channel.

[0020] Furthermore, the delivery rod includes a closed end, which is an end that passes through the first section and enters the blood vessel first when implanted.

[0021] Furthermore, one end of the main channel opening includes point A, and a developing identification point is provided at point A. Another developing identification point is provided at one end of the main channel opening at a position symmetrical to point A. The first branch includes point B at one end of the opening, and the second branch includes point C at one end of the opening. A developing identification point is provided at point B and point C respectively. The connection point between the first branch and the second branch at one end close to the main channel is point D. The line connecting point A and point B includes point E, and a developing identification point is also provided at point E. The last developing identification point is provided at a position symmetrical to point E about the axis of the main channel on the bracket structure. The distance from point E to point B or point A is 10mm-20mm, and the distance from point D to point E can be set to 3-5mm. The part of the connected bracket that enters the first branch or the second branch cannot pass through point D.

[0022] Alternatively, a developing mark point is arranged in an array on the outer wall of one end of the main channel, a developing mark line is arranged on the outer wall of the other end of the main channel, a developing mark point is arranged on the outer wall of the end of the first branch that is not connected to the main channel, and a developing mark point is arranged on the outer wall of the end of the second branch that is not connected to the main channel. The developing mark line can be set at point A or point E, the developing mark line is parallel to the axis of the delivery rod, and the developing mark line is parallel to the axis of the main channel. When the stent structure is inserted into the abdominal aorta by the delivery rod but not released, it is impossible to intuitively judge whether the first branch and the second branch can be aligned with the two iliac arteries. Since the stent structure cannot be rotated and adjusted after being released, releasing the stent structure when the first branch and the second branch are not aligned with the two iliac arteries will make it difficult to connect other stents later. By setting a development marking line, when the stent structure is inserted into the abdominal aorta by the delivery rod but not released, the rotation angle of the stent structure relative to the abdominal aorta can be judged by observing the position of the development marking line on the stent structure in the development image. If the development marking line is shown in the image at the edge of the outline of the stent structure, the first branch and the second branch are aligned with the two iliac arteries respectively; if the development marking line is shown in the image at the center of the outline of the stent structure, the deflection angle of the stent structure and the two iliac arteries is large. At this time, the deflecting delivery rod rotates the stent structure, thereby moving the development marking line to the edge of the outline of the stent structure in the imaging. At this time, releasing the stent structure can ensure that the first branch and the second branch are aligned with the two iliac arteries respectively.

[0023] Beneficial effects of the present invention:

[0024] 1. By adopting a balloon dilatation scheme and setting development marking points, the stent graft can be released at an accurate position without displacement along the blood vessel during the release process. The user can grasp the position change of the stent graft in the blood vessel so as to fine-tune the stent graft through the delivery rod, thereby ensuring the accuracy of positioning and effectively solving the problem of arterial stenosis and occlusion.

[0025] 2. By placing the covered stent above the bifurcation of the blood vessel and allowing the first branch and the second branch to connect with the stent, the connected stent enters the branch blood vessel and reshapes the shape of the bifurcation of the abdominal aorta. The covered stent can press the thrombus or plaque on the wall of the vessel to prevent it from falling off, thereby making it have excellent practical effects. The stent can be designed with different lengths and diameters, and can be connected with connecting stents of different lengths, so that the total length of the covered stent can be adjusted, and thus it can be suitable for stenosis areas of blood vessels of different lengths, and has excellent practical effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the present invention after the balloon is filled;

[0027] Figure 2is a schematic diagram of the cross-sectional structure of the support structure;

[0028] Figure 3 It is a schematic diagram of the cross-sectional structure of the present invention when the balloon is in an initial state;

[0029] Figure 4 is a schematic diagram of the overall cross section after the balloon is emptied;

[0030] Figure 5 It is a schematic diagram of the overall structure of the present invention when point A is replaced with a developing marking line;

[0031] Figure 6 It is a schematic diagram of the local structure of the present invention after the protective outer sheath is sleeved when the balloon is emptied;

[0032] In the figure, 1. stent structure; 11. main channel; 12. first branch; 13. second branch; 14. coating layer; 15. development mark point; 2. balloon; 21. first section; 22. second section; 23. delivery rod; 231. traction guide wire; 232. closed end; 233. guide wire cavity; 24. filling cavity; 3. protective outer sheath; 4. point A; 5. point B; 6. point C; 7. point D; 8. point E; 9. development mark line. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention are described clearly and completely below through specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation methods. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in 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] A balloon-expandable covered stent for arterial occlusion, such as Figure 1-5As shown, it includes: a balloon-expandable covered stent for arterial occlusion, including: a stent structure 1, including a main channel 11, a first branch 12 and a second branch 13, the first branch 12 and the second branch 13 are both connected to the same end of the main channel 11; a balloon 2, a filling cavity 24 is provided inside the balloon 2, the balloon 2 expands when the filling cavity 24 is filled, and the balloon 2 contracts when the filling cavity 24 is emptied, and is sleeved on the stent structure 1 in an empty state, including a first section 21 and a second section 22, the first section 21 is sleeved on the first branch 12, the second section 22 is sleeved on the second branch 13, the first section 21 and the second section 22 are connected in the main channel 11, wherein the main channel 11, the first branch 12 and the second branch 13 are all mesh structures, and both sides of the mesh structure are lined with a coating layer 14. The material of the coating layer 14 is expanded polytetrafluoroethylene; the material of the mesh structure is nickel-titanium alloy. When in use, the existing herringbone covered stent needs to be placed at the bifurcation of the abdominal aorta and the bilateral iliac arteries so that the two legs of the herringbone covered stent are respectively inserted into the bilateral iliac arteries. However, since the herringbone covered stent needs to be inserted into the abdominal aorta through one iliac artery, after the herringbone covered stent as a whole enters the abdominal aorta, it needs to be pulled back along the insertion path so that one of the branches of the covered stent is inserted into the other iliac artery. However, since the covered stent can rotate around the axis of the abdominal aorta in the abdominal aorta, the landing point of the branch of the covered stent is not necessarily the entrance of the iliac artery when pulling back. Moreover, for stenotic and occlusive lesions of the abdominal aorta and iliac arteries, the arterial lumen is narrow, making it difficult to rotate or withdraw the stent in the blood vessel. Therefore, this operation has a high degree of implementation difficulty, and the entrance of the bilateral iliac arteries may be difficult to insert due to the occlusive lesions of the blood vessels. It often takes multiple attempts to insert the two legs of the herringbone covered stent into the bilateral iliac arteries. In the present application, one of the branches of the covered stent is connected to a guide wire during implantation, and the purpose of the guide wire is to push the covered stent into the abdominal aorta through one of the bilateral iliac arteries, and after the covered stent enters the abdominal aorta, there is no need and no way to insert the first branch 12 and the second branch 13 into the bilateral iliac arteries respectively.

[0036] A more preferred embodiment is as follows Figure 1-5As shown, the stent structure 1 is integrally formed, and the side walls of the first branch 12 and the second branch 13 are joined to each other. The end of any structure on the coated stent close to the abdominal aorta is defined as the proximal end, and the end close to the double iliac arteries is defined as the distal end. When in use, the coated stent is first inserted into the abdominal aorta. Specifically, it is the same as the prior art: the balloon 2 penetrated by the delivery rod 23 and the stent structure 1 attached to the surface of the balloon 2 are extended into the iliac artery, and the coated stent is delivered through one of the double iliac arteries and finally passes through the bifurcation into the abdominal aorta. After implantation, the stent graft is located in the abdominal aorta as a whole, and the first branch 12 and the second branch 13 face the bifurcation of the bilateral iliac arteries. After that, the stent structure 1 does not need to be moved any more, and multiple other stents can be connected to the first branch 12 and the second branch 13 according to the occlusion situation in the bilateral iliac arteries, so as to open the occluded blood vessels of any length; when the distance between the distal end of the first branch 12 and the bifurcation of the bilateral iliac arteries is a, stop and start the expansion and positioning of the balloon 2. When the balloon 2 expands, the distal end of the balloon 2 will need a space beyond the stent, so 3mm≤a≤10m m, so that the present stent graft has the following differences from the existing stent grafts: there is no need to insert the first branch 12 and the second branch 13 into the double iliac arteries respectively, more stents are placed from the double iliac arteries, and these stents are successively connected to the distal ends of the first branch 12 and the second branch 13 of the earlier placed stent graft, so that the length of the expansion area can be adjusted and the positioning is accurate, and the bifurcation morphology of the abdominal aorta can be reconstructed at the same time, thereby overcoming the problems of the existing technology in application that it is difficult to place the branches of the stent into the double iliac arteries and cannot reconstruct the bifurcation morphology of the abdominal aorta.

[0037] A more preferred embodiment is as follows Figure 1-5 As shown, in the axial direction of the main channel 11, the length of the mesh structure is equal to the length of the coating layer 14; in the axial direction of the first branch 12, the length of the mesh structure is equal to the length of the coating layer 14; in the axial direction of the second branch 13, the length of the mesh structure is equal to the length of the coating layer 14. There are marks on the first branch 12 and the second branch 13 for connecting other stents of different types. The specific connection operation is: after the stent structure 1 is positioned, the other stents are placed into the first branch 12 or the second branch 13 through the bilateral iliac arteries, and the connection with the first branch 12 or the second branch 13 is completed. The more specific connection structure or connection method belongs to the prior art.

[0038] A more preferred embodiment is as follows Figure 1-5As shown, the balloon 2 is also connected with a pulling guide wire 231, one end of which is connected to the inner wall of the second section 22, the other end of which penetrates the stent structure 1 from the second branch 13 and exits from the first branch 12, and the other end of which extends out of the patient's body along the delivery rod 23. In the emptying state, the delivery rod 23 is pushed toward the abdominal aorta so that the balloon 2 is separated from the stent structure 1 in the axial direction of the main channel 11, and then the pulling guide wire 231 is pulled so that the second section 22 is attached to the first section 21, and finally the balloon 2 is withdrawn from the patient's body through the first branch 12. The purpose of setting the pulling guide wire 231 is to pull the second section 22 placed in the second branch 13 back to the first branch 12 where the first section 21 is located, so that the balloon 2 can be more smoothly detached from the stent structure 1, and the balloon 2 will not be scratched with the bifurcation of the stent structure 1 during the detachment process. Before releasing the stent structure, the pulling guide wire 231 is passed through the stent structure 1 and is located outside the balloon 2 ; one end of the delivery rod 23 passing through the balloon 2 is a closed end 232 .

[0039] Another more preferred embodiment is that after the stent is deployed and positioned, the balloon 2 is emptied and the delivery rod 23 is pushed toward the abdominal aorta, so that both the first section 21 and the second section 22 enter the main channel 11, and then the delivery device and the pulling guide wire 231 are synchronously withdrawn to the outside along the iliac artery serving as the insertion path, so that the balloon 2 can be pulled out of the body.

[0040] A more preferred embodiment is as follows Figure 1-5 As shown, the stent structure 1 further includes spherical development marking points 15, which are connected to the outer wall of the stent structure 1. Specifically, each development marking point 15 is arranged on the coating layer 14; or, the development marking point 15 is arranged on the mesh structure and is coated with the mesh structure, so in this way, the diameter of the development marking point 15 is greater than the thickness of the coating layer 14. A development enhancer is coated on each development marking point 15, so that the operator can observe the rotation of the coated stent about the abdominal aorta in the patient's body in vitro.

[0041] Another more preferred embodiment is that array sheets are vertically arranged on the surface of the development mark point 15, and the interval between the array sheets is not less than the wavelength of the ultrasonic wave used in development, so that the development effect can be enhanced without applying a development enhancer.

[0042] A more preferred embodiment is as follows Figure 1-5As shown, one end of the main channel 11 opening includes point A 4, and a developing mark point 15 is provided at point A 4. Another developing mark point 15 is provided at one end of the main channel 11 opening at a position symmetrical to point A 4. The first branch 12 and the second branch 13 include point B 5 and point C 6 at the far end, respectively, and a developing mark point 15 is provided at point B 5 and point C 6, respectively. The connection point of the first branch 12 and the second branch 13 at one end close to the main channel 11 is point D 7. The line connecting point A 4 and point B 5 includes point E 8, and a developing mark point 15 is also provided at point E 8. The last developing mark point 15 is provided at a position symmetrical to point E 8 about the axis of the main channel 11 on the support structure 1. The distance from point E 8 to point B 5 is 10mm-20mm, and the distance from point D 7 to point E 8 can be set to 3-5mm. The best end position of the connected stent entering the first branch 12 or the second branch 13 is point E 8 and cannot go beyond point D 7. When the connected stent goes beyond point D 7, it forms a kissing stent, which will squeeze and collide with each other in the main channel 11. After the stent structure 1 enters the abdominal aorta, the three imaging marking points 15 on each side of the stent structure 1 or the straight line formed by two imaging marking points 15 and a imaging marking line 9 are parallel to the axis of the main channel 11.

[0043] Another more preferred embodiment is that the position of point A 4 or point E 8 is a developing mark line 9, and the developing mark line 9 is parallel to the axis of the delivery rod 23. When the stent structure 1 is placed into the abdominal aorta by the delivery rod 23 but not released, it is impossible to intuitively judge whether the first branch 12 and the second branch 13 can be aligned with the two iliac arteries. When the two branches are aligned with the two iliac arteries, the stent structure 1 is in the left-right position, and when the two branches are not aligned with the two iliac arteries and the offset is the largest, the stent structure 1 is in the front-back position. Since the stent structure 1 cannot be rotated and adjusted after being released, releasing the stent structure 1 when the stent structure 1 is in the front-back position will make it difficult to connect other stents later. By setting the development marking line 9, when the stent structure 1 is inserted into the abdominal aorta by the delivery rod 23 but not released, the rotation angle of the stent structure 1 relative to the abdominal aorta can be judged by observing the position of the development marking line 9 on the stent structure 1 in the development image. If the development marking line 9 is shown in the image to be at the edge of the contour of the stent structure 1, the first branch 12 and the second branch 13 are respectively aligned with the two iliac arteries; if the development marking line 9 is shown in the image to be at the center of the contour of the stent structure 1, the deflection angle of the stent structure 1 and the two iliac arteries is large. At this time, the deflection delivery rod 23 causes the stent structure 1 to rotate, thereby causing the development marking line 9 to move to the edge of the contour of the stent structure 1 in the imaging. At this time, releasing the stent structure 1 can ensure that the first branch 12 and the second branch 13 are respectively aligned with the two iliac arteries. The manufacturing material of the development marking line 9 is the same as that of the development marking point 15.

[0044] A more preferred embodiment is as follows Figure 1-5As shown, two imaging marking points 15 are laid out in a circular array on the outer walls at both ends of the main channel 11, and the first branch 12 and the second branch 13 are respectively provided with imaging marking points 15 10 mm away from the far end for marking when connecting the bracket.

[0045] A more preferred embodiment is as follows Figure 1-5 As shown, the length of the first branch 12 is the same as that of the second branch 13. Compared with the long-short leg design in the prior art, the stent structure 1 in this embodiment is conducive to reducing the risk of tilting or scratching caused by the different surface areas on both sides when the coated stent moves in the blood vessel. Since the lengths of the first branch 12 and the second branch 13 are the same, the spacing between different imaging marking points 15 on the first branch 12 and the second branch 13 is the same. Although the operator cannot distinguish the left and right of the two branches of the stent structure 1 based on this difference in the imaging image, the deployment effect of the stent body can still be analyzed based on whether the three imaging marking points 15 on each side of the imaging image are in a straight line. If the imaging marking points 15 on each side can be in a straight line, it indicates that the stent structure 1 before deployment is intact, or the stent structure 1 is deployed successfully; if the imaging marking points 15 on at least one side cannot be in a straight line, it indicates that the stent structure 1 before deployment is deformed, the stent structure 1 fails to be deployed, or one of the branches is stuck on the blood vessel wall. Therefore, the unequal lengths of the first branch 12 and the second branch 13 combined with the setting of the imaging mark 15 can better facilitate the operator to grasp the state of the stent graft. In addition, since the stent graft does not need to be inserted into the bilateral iliac arteries respectively, the rotation of the stent structure 1 around the vascular axis does not affect the use of the stent graft.

[0046] A more preferred embodiment is as follows Figure 1-5 As shown, the diameter of the main channel 11 ranges from 12 mm to 30 mm, and the axial length of the main channel 11 is at least 35 mm; the diameter of the first branch 12 ranges from 6 mm to 12 mm, and the diameter of the second branch 13 is the same as the diameter of the first branch 12 .

[0047] A more preferred embodiment is as follows Figure 1-5As shown, the balloon 2 is similar to a pair of trousers as a whole, and its symmetrical two sides are respectively the first section 21 and the second section 22. There is a merged part between the first section 21 and the second section 22. The end of the first section 21 is connected to an external pump device through a guidewire cavity 233. The pump device is used to inject or suck out fluid into the balloon 2 through a catheter, so as to expand or shrink the balloon 2. The perfusion device and the catheter are both prior art. The balloon 2 is placed in an undeployed stent in an empty state. After the balloon 2 is expanded, it has an initial state. In the initial state, the lengths of the first section 21 and the second section 22 are the same. In the initial state, the maximum diameter of the merged part of the first section 21 and the second section 22 is not less than twice the maximum diameter of the first section 21 or the second section 22, so as to ensure that the stent structure 1 can be fully and fully deployed. In the initial state, the length difference between the first section 21 and the second section 22 is zero, and there is no risk of detaching from the stent structure 1 during expansion; in this embodiment, the first section 21 and the second section 22 do not have a length difference, so that the first section 21 and the first branch 12 can achieve length adaptation, and the second branch 13 and the second section 22 can achieve length adaptation. The balloon 2 has a withdrawn state after contraction, and in the withdrawn state, the second section 22 is completely moved from the second branch 13 to the main channel 11. Specifically, when the balloon 2 is expanded and the stent structure 1 is fully deployed and positioned, the balloon 2 is contracted by the perfusion device. At this time, a guide wire can be inserted into the second branch 13 through the branch blood vessels of the aorta and iliac arteries, so that the second section 22 can be pushed out toward the distal end of the stent structure 1, and then the shape of the balloon 2 is adjusted to the withdrawn state. At this time, the delivery rod 23 connected to the balloon 2 can be pulled to completely withdraw the balloon 2 from the stent structure 1.

[0048] Example 2

[0049] A more preferred embodiment is as follows Figure 6 As shown, the stent structure 1 is delivered into the abdominal aorta by pushing the delivery rod 23 connected to the balloon 2, and the balloon 2 and the stent structure 1 are in contact with each other by surface tension and friction. Therefore, there is a risk of unloading of the stent structure 1 during the implantation process, so that the stent structure 1 and the balloon 2 are separated during the implantation process. Therefore, this embodiment is different from embodiment 1. A protective outer sheath 3 is sleeved on the outside of the stent structure 1 to prevent the stent structure 1 sleeved on the balloon 2 from being scratched and falling off from the blood vessel wall along the way during the implantation process of the abdominal aorta. After the stent structure 1 is implanted into the abdominal aorta, the protective sheath is first withdrawn, and then the balloon 2 is filled to unfold and release the stent; after releasing the stent, the balloon 2 is emptied and then pushed into the abdominal aorta so that the balloon 2 leaves the stent, and then the traction guide wire is pulled so that the second section 22 is attached to the first section 21, and then the balloon 2 is pulled back as a whole through the first branch 12 into the protective outer sheath 3 still in the iliac artery, and finally the protective outer sheath 3 and the balloon 2 are simultaneously removed from the iliac artery.

Claims

1. A balloon-expandable covered stent for arterial occlusion, characterized in that: include: A support structure, comprising a main channel, a first branch and a second branch, wherein the first branch and the second branch are both connected to the same end of the main channel, an axis of the first branch is parallel to an axis of the second branch, and an axis of the first branch is parallel to an axis of the main channel; The balloon is similar to a pair of trousers as a whole, and has two symmetrical sides, namely a first section and a second section, and there is a merged portion between the first section and the second section, which is sleeved on the support structure in an empty state, the first section is sleeved on the first branch, the second section is sleeved on the second branch, and the first section and the second section are connected in the main channel; The support structure also includes a developing mark point, which is connected to the outer wall of the support structure; two developing mark points are arranged in an array on the outer walls of both ends of the main channel, one developing mark point is arranged on the outer wall of the end of the first branch that is not connected to the main channel, and one developing mark point is arranged on the outer wall of the end of the second branch that is not connected to the main channel; The balloon is also connected to a traction guide wire, one end of which is connected to the inner wall of the second section, the other end of which passes through the stent structure from the second branch and out from the first branch, and the other end of which extends out of the patient's body along the delivery rod.

2. The balloon-expandable covered stent for arterial occlusion according to claim 1, characterized in that: The length and diameter of the first branch are the same as those of the second branch.

3. The balloon-expandable covered stent for arterial occlusion according to claim 2, characterized in that: The diameter of the main channel ranges from 12 mm to 30 mm, the axial length of the main channel is at least 35 mm, the diameter of the first branch ranges from 6 mm to 12 mm, and the diameter of the second branch is the same as the diameter of the first branch.

4. The balloon-expandable covered stent for arterial occlusion according to claim 3, characterized in that: The balloon has an initial state after expansion, and in the initial state, the lengths of the first section and the second section are the same.

5. The balloon-expandable covered stent for arterial occlusion according to claim 4, characterized in that: A guidewire cavity is provided in the balloon, and the guidewire cavity is arranged through the first section. A filling cavity and a delivery rod are provided in the balloon, and a guidewire cavity is provided in the delivery rod, and the delivery rod is arranged through the first section. One end of the delivery rod is arranged outside the first section, and the other end of the delivery rod is retained outside the patient's body through the blood vessel.

Images