Aortic arch stent graft

Abstract

The utility model discloses an aortic arch covered stent, including support body, support body is covered stent, and the recessed portion is formed to the inside recess of the outer wall of support body middle part from its one side, and the covered inner platform is equipped with in the recessed portion of support body, and the aortic arch covered stent still is equipped with at least one arch outer support, the covered outer overhang of covered inner platform is located in the arch outer support one end, and the other end is fixed with covered inner platform, to block covered inner platform to adhere aortic arch big bending side. The utility model has solved the cerebral ischemia, the need extracorporeal circulation, the difficulty of guide wire into branch stent, the branch stent easy to close, the operation difficulty, the need to block branch blood vessel, the chimney stent inner leakage and other problems in the process of aortic arch three branch luminal reconstruction.

Description

Technical Field

[0001] This utility model belongs to the field of medical device technology, specifically an aortic arch endovascular stent graft. Background Technology

[0002] The aortic arch is the curved, arched portion of the upper aorta. With an aging population and increasing prevalence of hypertension and arteriosclerosis, the number of patients with aortic disease is rising annually. Type A aortic dissection, involving the aortic arch, accounts for 70% of aortic dissections, and these patients still primarily require open surgery. However, open surgery is highly invasive, requiring cardiopulmonary bypass or even deep hypothermic circulatory arrest, resulting in longer operation times, a higher probability of postoperative complications, and a higher mortality rate. Minimally invasive treatment of aortic arch diseases represents the goal of aortic disease treatment after achieving minimally invasive treatment for simpler lesions.

[0003] The integrated endovascular reconstruction technique of the three branches of the aortic arch is the pinnacle of endovascular reconstruction techniques. Currently, endovascular ablation techniques are mainly used for non-major branch segments such as the descending aorta and for branch vessels where there are no strict requirements for operation time and blood flow occlusion, such as the abdominal aorta-iliac artery. The thoracic aortic arch has three important branch vessels responsible for supplying blood to the brain and upper limbs. The cerebral blood supply occlusion time cannot be too long; ischemia exceeding ten minutes can lead to severe and irreversible brain damage due to hypoxia. The diameter, spacing, location, and course of the three branches vary from person to person. These factors mean that multi-branch designs are difficult to meet most clinical needs, and the operation is more difficult with a higher surgical complication rate. Furthermore, the aortic arch is adjacent to the ascending aorta, the largest blood vessel in the human body. In addition to serving as a blood flow channel, the ascending aorta also relies on its elasticity to maintain stable blood pressure.

[0004] Currently, endovascular repair of the ascending aorta using combined embedded branches, while simpler with multiple branch stents, presents several challenges:

[0005] I. The chimney technology, which uses parallel main and branch supports, offers flexible branch support combinations and is relatively simple to operate. However, the chimney technology is prone to internal leakage due to the obvious grooves at the edges where the branch supports meet the main body. Using the chimney technology for all three branch supports will result in severe internal leakage, making it difficult to reconstruct the three branches on the arch using this technology.

[0006] Second, the positioning accuracy is poor, and the surgical technique is too demanding. Because the ascending aorta gathers blood from sources other than the coronary arteries, the blood flow velocity and impact force are very high, resulting in poor precision in the main body release.

[0007] Third, the overlapping combination of multiple stents in the ascending aorta and aortic arch brings many negative effects, such as severe loss of elasticity of the ascending aorta and aortic arch, resulting in loss of blood pressure regulation function. It also leads to continuous friction between the metal stents (due to pulsation), significantly reducing stent durability. The risk of endoleak between overlapping interfaces is high, and it is more difficult to insert the guidewire into the embedded branch, resulting in excessively long operation time.

[0008] Fourth, the number of embedded branches is insufficient, requiring the closure of one branch vessel or bypass surgery, increasing the difficulty of the operation and posing a risk of ischemia. The existing delivery system has an excessively large diameter, making it difficult to navigate the aorta. Furthermore, the ascending aorta to descending aorta forms a 180° bend, which makes it difficult for the delivery system to pass through patients with small bending radii.

[0009] Fifth, three-branch vessels require one vessel to supply blood in reverse, resulting in poor blood supply. There are requirements for the spacing between branches, making stent placement difficult during deployment and demanding high surgical skill.

[0010] 6. The stent's poor flexibility makes it unsuitable for patients with small curvatures. It can affect cerebral blood flow, limiting surgical effectiveness. Guidewire entry into small branch openings is difficult, leading to longer operation times. Excessive anastomoses in the drape challenge the stability of the drape structure.

[0011] The aforementioned problems limit the widespread adoption of endovascular repair therapy for the aortic arch.

[0012] Related terms:

[0013] The aortic arch is the arched, curved portion of the upper aorta. Three major arteries emerge from the convex side of the arch, from right to left: the brachiocephalic trunk (innominate artery), the left common carotid artery, and the left subclavian artery. The aortic arch connects to the ascending aorta anteriorly and the descending aorta posteriorly.

[0014] Aortic syndrome mainly includes aortic dissection, aortic wall hematoma, and penetrating aortic ulcer.

[0015] Extracorporeal circulation: The purpose of extracorporeal circulation is to maintain the body's blood supply during open surgery. This is a life support technique that uses a series of specialized artificial devices to drain blood from the veins back into the body, artificially exchange gases, regulate temperature, and filter the blood before returning it to the arterial system. Extracorporeal circulation, also known as cardiopulmonary bypass, involves artificial devices replacing human bodily functions.

[0016] Deep hypothermic circulatory arrest: a measure to reduce oxygen consumption in the body, especially the brain. It involves establishing extracorporeal circulation, lowering the body's core temperature to 18-20°C, and then stopping the extracorporeal circulation; after completing heart and major vascular surgery, extracorporeal circulation is then resumed to restore body temperature; finally, extracorporeal circulation is stopped. It is used for the correction of complex heart malformations in infants and young children, and for surgeries involving the ascending aorta and aortic arch.

[0017] Endovascular aortic repair: Endovascular aortic repair is a minimally invasive endovascular treatment technique that involves inserting a stent through a femoral artery incision to the diseased area of ​​the aorta, repairing the aortic lesion from within the arterial lumen, thus avoiding open surgery. Compared with traditional surgery, endovascular aortic repair significantly reduces surgical trauma, substantially shortens operation time, and reduces surgical complications and mortality.

[0018] The greater curvature of the aortic arch: the convex side of the aortic arch, that is, the side where the aortic arch connects to the three branch arteries.

[0019] Lesser curvature side of the aortic arch: the concave side of the aortic arch. Utility Model Content

[0020] To address the aforementioned problems in existing technologies, the purpose of this invention is to solve the issues of excessive product specifications, high operational difficulty, tight operation time, and high complication rates in endovascular repair of thoracic aortic lesions involving the aortic arch. This invention provides an aortic arch endovascular stent graft system that solves problems such as cerebral ischemia, the need for cardiopulmonary bypass, difficulty in guidewire insertion into branch stents, easy occlusion of branch stents, high surgical difficulty, the need to seal branch vessels, and leakage within the chimney stent during endovascular reconstruction of the three branches of the aortic arch. This makes endovascular repair of lesions involving the aortic arch simpler, easier, less difficult, and shorter in operation, facilitating wider application, improving postoperative outcomes, and reducing complications.

[0021] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0022] A endovascular stent graft for aortic arch includes a stent body, which is a endovascular stent graft. A recess is formed in the middle of the stent body from one side of its outer wall. An inner endovascular platform is provided in the recess. The aortic arch endovascular stent graft also includes at least one outer endovascular stent. One end of the outer endovascular stent is connected to the inner endovascular platform, and the other end extends out of the platform and is located within the recess to prevent the inner endovascular platform from adhering to the greater curvature of the aortic arch. In other words, one end of the outer endovascular stent is suspended outside the inner endovascular platform, while the other end is fixed to the inner endovascular platform.

[0023] As a further improvement to the above technical solution:

[0024] The external support of the bow is an elastic support.

[0025] The outer support of the bow is a non-linear linear structure.

[0026] The stent body also includes a first end and a second end arranged and connected sequentially along the axial direction. The inner lining collapse is located between the first and second ends. The outer stent is fixed to the outside of the stent body. The portion of the outer stent located in the recessed area has a large single-waveform structure. This waveform is not fixed to the lining and forms a semi-circular space axially with the collapsed lining. The remaining portion of the outer stent has a small-wave multi-waveform structure, fixed to the inner lining collapse without affecting the bending performance of the stent. The main stent can easily bend to this side to conform to the arch structure. This ensures that the lining at the inner lining collapse platform does not adhere to the vessel wall on the large bend side of the arch during stent implantation. This ensures that branch blood flow is not interrupted during stent implantation. Simultaneously, the main stent does not compress the branch vessel stent, avoiding the risk of branch stent kinking or collapse due to compression from the main stent. The completely suspended portion of the outer stent has a large waveform structure with the peak pointing distally, facilitating stent loading, release, and position adjustment during release. Meanwhile, the single-wave structure has minimal impact on the bridging of the branched covered stent, and it is also easier to adjust the position of the external stent during the implantation of the branched covered stent. Specifically, the portion of the external stent located in the recess includes two arc-shaped filaments, which are symmetrically arranged. One end of one filament is connected to the inner collapse of the covered stent, and the other end extends towards the second end of the stent body, gradually moving away from the inner collapse of the covered stent, and then connects to one end of the other filament. The concave side of the filament faces the inner collapse of the covered stent.

[0027] The aortic arch endovascular stent graft has at least two external stents, which are spaced apart along the axial direction of the stent body.

[0028] The main body of the support includes a first end, a membrane inner collapse platform and a second end arranged and connected in sequence along the axial direction. Three embedded branches are provided inside the main body of the support. One embedded branch is embedded in the membrane inner collapse platform and the other two embedded branches are embedded in the first end. The opening at the connection between the first end and the membrane inner collapse platform is directly opposite the recessed part and connects the inside and outside of the membrane of the main body.

[0029] The embedded branch, which is embedded in the inner collapse platform of the film, is inclined relative to the inner collapse platform of the film. The opening of the embedded branch near the second end faces the recess and connects the inner and outer sides of the film.

[0030] The axial direction of the embedded branch located in the inner collapse platform of the membrane is not parallel to the axial direction of the support body, and the tilt angle is towards the second end.

[0031] The main body of the support includes a first end, a membrane-covered inner collapse platform and a second end arranged and connected sequentially along the axial direction. The three embedded branches are all located in the first end on the same side of the membrane-covered inner collapse platform, and the openings of the three embedded branches are in the same direction but not all in the same plane.

[0032] The main body of the support is equipped with a restraint component, which restrains the main body of the support to a retracted state. Releasing the restraint component releases the main body of the support to an extended state.

[0033] The beneficial effects of this utility model are:

[0034] 1. The procedure will not block blood flow to the aorta and supra-arch branches, which will significantly reduce the complications caused by intracranial ischemia during trans-arch endovascular repair and significantly reduce the time limit for stent reconstruction during trans-arch repair. The surgeon can proceed with the surgery at a more relaxed pace, thereby achieving better surgical operation and reducing the difficulty of the operation.

[0035] 2. The design of the arch-outer stent in the recessed part ensures that the endovascular stent will not collapse due to factors such as delivery device or vascular configuration, and will not be attached to the greater curvature of the aortic arch, thus avoiding the risk of blood flow blockage before branch vessel reconstruction. It also ensures that the blood flow of the branch branches will not be interrupted during the branch stent (embedded branch) bridging process, and at the same time ensures that the main stent will not compress the branch stent, causing the branch stent to collapse.

[0036] 3. Multiple embedded branches are set up, and embedded branches are also set up in the covered collapse platform, corresponding to multiple supra-arc branch vessels. This reduces the space for guidewires inserted into branch vessels to advance, so that guidewires inserted into branch vessels can be easily inserted into embedded branches. The "upward" setting of the third branch keeps the axis of the third branch at a suitable angle, so that the corresponding peripheral covered stent can connect to the third branch more smoothly during reconstruction. At the same time, since the third branch is located in the covered collapse platform, the distance between the left subclavian artery and the third branch is closer than that of the embedded branch located in the first end. Therefore, the guidewire in the left subclavian artery can be superselectively inserted into the third branch more quickly and accurately.

[0037] 4. The first and second branches are designed side by side to avoid the problem of not being able to adapt to different branch spacing, angles, sizes, and number of branches (some people have a close distance between the brachiocephalic trunk and the left carotid trunk, and there are also cases where the brachiocephalic trunk and the left carotid trunk share a trunk). The distance between the exit of the third branch and the exit of the first branch is less than the distance of the anterior edge of the opening of the corresponding branch vessel in most patients. The above design allows all branch vessels to be reconstructed without ischemia, diversion, or endoleak. It does not change the blood flow direction of the branch vessels, has little impact on hemodynamics, and can meet the problems of different spacing, angles, and shared trunks of the supraclavicular branch vessels. It avoids the problem that the reverse blood flow scheme is difficult to reconstruct when the angle between the left subclavian artery and the aorta is too small.

[0038] 5. The covered stent is an integrated stent, which is simpler to operate, has a shorter operation time, and less blood loss. It avoids the problem of multiple aortic stents overlapping in the ascending aorta and aortic arch, which can cause a significant reduction or loss of elasticity of the ascending aorta and aortic arch, resulting in the loss of blood pressure regulation function of the ascending aorta. The integrated stent design preserves the blood pressure regulation function of the ascending aorta as much as possible, and avoids the risk of reduced durability, stent breakage, and endoleak at the connection point caused by the overlapping and mutual friction of multiple aortic stents.

[0039] 6. The covered stent will not compress the peripheral covered stent of the reconstructed branch vessels, thus avoiding the risk of branch stent occlusion due to compression.

[0040] 7. The covered stent is equipped with markers indicating the positions of each component, which facilitates the installation of the covered stent and the positioning and adjustment of each component during the operation.

[0041] 8. Embedded branches are positioned proximal to the corresponding branch vessels to ensure that the blood flow direction of the branches is not altered after reconstruction. The combination of covered stents and peripheral covered stents achieves branch reconstruction, reducing the number of stent sizes. With a relatively small number of sizes, it addresses issues such as the diameter before and after the arch, lesion length, spacing and angle of branches on the arch, and significant differences in branch diameter. This avoids the limitations of customization and meets the needs of most anatomical structures with a relatively small number of sizes. All three branches on the arch use antegrade blood flow, which is more in line with hemodynamics. Compared to the retrograde blood flow reconstruction of the left subclavian artery, this approach is simpler in branch reconstruction, has better blood supply, lower risk of branch stent occlusion, and can be used in patients with a small angle between the left subclavian artery and the aorta (because a small angle between the left subclavian artery and the descending aorta makes retrograde blood flow reconstruction of the left subclavian artery difficult to achieve, the delivery system cannot achieve a near 180-degree sharp turn, and excessive bending can easily lead to occlusion of the covered stent).

[0042] 9. It can meet all the reconstruction needs of the left subclavian artery, while not changing the blood flow direction of the branch vessels, avoiding long-length reverse blood flow in the left subclavian artery, and overcoming the problem of difficult reconstruction of reverse embedded branches when the angle between the left subclavian artery and the aorta is too small. Attached Figure Description

[0043] Figure 1 This is a structural schematic diagram of one embodiment of the present invention.

[0044] Figure 2 This is a schematic diagram of another embodiment of the present invention.

[0045] Figure 3 This is a schematic diagram of the thoracic aorta.

[0046] Figure 4 This is a schematic diagram of a covered stent located in the thoracic aorta and partially unfolded, according to one embodiment of the present invention.

[0047] Figure 5 This is a schematic diagram of the three-branch blood flow in the arch portion of the covered stent after it is fully deployed, according to one embodiment of this utility model.

[0048] Figure 6 This is a schematic diagram of the head and arm trunk after reconstruction according to one embodiment of this utility model.

[0049] Figure 7 This is a schematic diagram of the brachiocephalic trunk and left common carotid artery after reconstruction according to one embodiment of this utility model.

[0050] Figure 8 This is a schematic diagram of the reconstructed three branches of the bow according to one embodiment of the present invention. Detailed Implementation

[0051] The specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of this utility model.

[0052] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0053] Example 1

[0054] A type of aortic arch covered stent, such as Figure 1 and 2 As shown, this is a self-expanding stent, consisting of a stent body 1 and three embedded branches 2. The stent body 1 and the embedded branches 2 have similar structures, both supported by a metal stent and a membrane 4. The membrane collapses in the middle of the stent body 1, forming an inner collapse platform 103, which is formed by a depression from the outer wall of the middle part of the stent body 1 towards the center of the stent body 1. In other words, the stent body 1 can be regarded as being formed by a central depression of a tubular structure with a circular cross-section. The cross-section of the inner collapse platform 103 is arc-shaped or quasi-arc-shaped, meaning that the cross-section of the inner collapse platform 103 is equivalent to the structure remaining after a circle has been partially cut off by a straight or non-straight line.

[0055] As described above, the main body 1 of the support is divided into three parts: a first end 101, a membrane-covered inner collapse platform 103, and a second end 102 arranged sequentially along the axial direction. That is, the left and right sides of the membrane-covered inner collapse platform 103 are the first end 101 and the second end 102, respectively. Obviously, the first end 101 and the second end 102 of the support body 1 are connected by the membrane-covered inner collapse platform 103, and the space left by the recess on the outside of the membrane-covered inner collapse platform 103 between the first end 101 and the second end 102 is the recessed portion 5.

[0056] The length direction of the support body 1 is its axial direction. The metal support at the first end 101 and the second end 102 includes multiple annular corrugated rings distributed along the axial direction, each annular corrugated ring including multiple crests and multiple troughs. The metal support at the inner collapse platform 103 of the membrane includes multiple arc-shaped corrugated rings distributed along the axial direction, each arc-shaped corrugated ring including multiple crests and multiple troughs. Each corrugated ring and at least one other corrugated ring are woven and connected by hooks or other means to achieve the connection of the entire metal support. The above-mentioned weaving connection method of the metal support is prior art and will not be described in detail here. The waveform setting of the corrugated rings makes the support body 1 elastic, allowing the support body 1 to expand or contract radially and bend axially.

[0057] The cross-sections of the inner collapse platform 103 may be equal or unequal. In this embodiment, the inner collapse platform 103 is not a structure with a constant cross-section, but rather a structure with a single step.

[0058] Three embedded branches 2 are installed inside the support body 1 and connected to the inner wall of the support body 1. The embedded branches 2 are also tubular structures. The three embedded branches 2 are a first branch 201, a second branch 202, and a third branch 203. The first branch 201 and the second branch 202 are located at the first end 101 of the support body 1, and the third branch 203 is located within the covered inner collapse platform 103 of the support body 1. The lengths of the first branch 201 and the second branch 202 are both less than the length of the first end 101 of the support body 1. When the covered support is in its natural state and not bent, the first branch 201 and the second branch 202 are arranged in parallel, and their axes are both parallel to the axis of the support body 1. One end opening of the first branch 201 and the second branch 202 faces the recess 5 on the outside of the covered inner collapse platform 103, and the opening of the first branch 201 and the opening of the second branch 202 at that end are flush, so as to reduce the size of the covered support. One end of the third branch 203 is located at the step of the inner collapse platform 103 of the membrane, directly opposite the recess 5. The axial direction of the third branch 203 is not parallel to the axial direction of the support body 1, and the axial direction of the third branch 203 points towards the recess 5 from the first end 101 of the support body 1 towards the second end 102. Figure 1As shown, when the recess 5 faces upward, the third branch 203 is arranged upward from the first end 101 towards the second end 102. The stepped arrangement of the covered endovascular platform 103 and the aforementioned upward arrangement of the third branch 203 facilitate the opening of one end of the third branch 203 facing the recess 5 at a better angle, which is conducive to the smooth bridging and reconstruction of the third branch 203 and the supra-arch branch vessels.

[0059] The first branch 201 and the second branch 202 can be used to reconstruct the brachiocephalic trunk and the left common carotid artery, respectively, and the third branch 203 is used to reconstruct the left subclavian artery. When the covered stent is located in the thoracic aorta, such as Figures 5-8 As shown, the first branch 201 and the second branch 202 are located within the ascending aorta, the endothelial collapse 103 is located within the aortic arch, the concave portion 5 faces the greater curvature of the aortic arch, and the concave portion 5 connects to the brachiocephalic trunk of the thoracic aorta, the left carotid artery, and the left subclavian artery.

[0060] The diameters of the three embedded branches 2 can be flexibly set, and the diameter of each embedded branch 2 is preferably designed to correspond to the median size of the branch vessel. The diameters of the three embedded branches 2 are equal, or the diameter of the first branch 201 is greater than the diameters of the second branch 202 and the third branch 203, and the diameters of the second branch 202 and the third branch 203 are equal. Alternatively, the diameter of the first branch 201 is equal to the diameter of the second branch 202.

[0061] The aortic arch endovascular stent graft also includes at least one external stent 3. One end of the external stent 3 is located within the recess 5 and is suspended, i.e., located on the outside of the endovascular graft 4. The other end of the external stent 3 is fixed (e.g., sutured) to the internal endovascular graft collapse 103 to prevent the internal endovascular graft collapse 103 from adhering to the greater curvature of the aortic arch. The inner side of the endovascular graft 4 refers to the space enclosed by the graft, while the outer side of the endovascular graft 4 refers to the space not enclosed by the endovascular graft 4.

[0062] The external arch support 3 is elastic. Preferably, the portion of the external arch support 3 located in the recess 5 is a non-linear linear structure. At least two external arch supports 3 are provided, and each external arch support 3 is arranged at intervals along the axial direction of the support body 1. The external arch support 3 is not covered with a membrane 4 for sewing.

[0063] In this embodiment, as Figure 1 and 2As shown, the portion of the outer arch support 3 located in the recessed portion 5 is V-shaped, with one end being a V-shaped opening and the other end being a apex. The outer arch support 3 is fixed to the outside of the support body 1. The inner side of the support body 1 refers to the space enclosed by the metal support or membrane 4 that makes up the support body 1, while the outer side of the support body 1 refers to the space not enclosed by the metal support or membrane 4. Therefore, the inner side of the support body 1 and the inner side of the membrane 4 are essentially the same, as are the outer side of the support body 1 and the outer side of the membrane 4. The portion of the outer arch support 3 located in the recessed portion 5 is a large single-waveform structure. This waveform is not fixed to the membrane and forms a semi-circular space axially with the collapsed membrane. The remaining portion of the outer arch support 3 is a small-wave multi-wave structure, fixed to the membrane inner collapse platform 103 without affecting the bending performance of the membrane support. Specifically, one end of the portion located in the recessed portion 5 is connected to the membrane inner collapse platform 103, and the other end extends into the recessed portion 5 towards the second end 102. Specifically, the portion of the outer arch support 3 located in the recessed portion 5 includes two curved filaments. These two filaments are symmetrically arranged and integrally connected. One end of one filament is connected to the inner collapse platform 103 of the membrane, while the other end extends towards the second end 102, gradually moving away from the inner collapse platform 103, and then connects to one end of the other filament. Preferably, the two filaments are smoothly connected to achieve a rounded corner effect.

[0064] In this embodiment, the metal stent at the inner collapse 103 of the endovascular membrane is designed as a single, independent semi-circular closed loop, sutured inside the endovascular membrane 4, giving the stent body 1 good flexibility to conform to any sharply curved arterial arch. The outer stent 3 is located between the first end 101 and the second end 102, and is sutured to the outer side of the endovascular membrane 4 at the inner collapse 103. In other words, the outer stent 3 and the metal stent at the inner collapse 103 are located inside and outside the endovascular membrane 4 at the inner collapse 103, respectively, and the outer stent 3 does not cover or support the endovascular membrane 4.

[0065] In this embodiment, the metal supports are all single-ring nickel-titanium wire supports.

[0066] Multiple restraints 6 are provided on the clasp 4. In this embodiment, the restraints 6 are fixing rope loops. One end of the restraint 6 is fixed to the metal support or clasp 4 of the stent body 1, and the other end is a free end. By fixing the free end of the restraint 6, the stent body 1 can be restrained, so that the stent body 1 is in a partially open state, which facilitates its placement in the correct position in the blood vessel. Specifically, the restraint 6 can be a single rope, which is wrapped around the stent body 1 to restrain the stent body 1, or it can be two ropes, one end of which is fixed to the stent body 1, and the other end is knotted together or fixed in other ways to restrain the stent body 1.

[0067] The covered stent is provided with multiple markers to achieve positioning of the covered stent. In this embodiment, the markers are a first marker 701, a first marker 702 of the first second branch, a second marker 703 of the first second branch, a first marker 704 of the third branch, a second marker 705 of the third branch, and a second marker 706, which are respectively used to mark the first end 101 of the covered stent, one end opening of the first branch 201 or the second branch 202, the other end opening of the first branch 201 or the second branch 202, one end opening of the third branch 203, the other end opening of the third branch 203, and the second end 102 of the covered stent.

[0068] Based on the above structure, the working process and principle of this utility model are as follows: After completing the supra-aortic three-branch puncture, guidewire 8 is first inserted into the ascending aorta. A stent delivery device pre-loaded with the covered stent is then inserted from the femoral artery. The stent delivery device delivers the covered stent to a predetermined position, such as... Figure 4 As shown, at this time, the covered stent is restrained by the restraint member 6 in a semi-expanded state and is not attached to the inner wall of the blood vessel. That is, blood can flow through both the inside and outside of the covered stent and it is in a freely adjustable state. At this time, the restraint member 6 is tied to a core wire made of metal. The position of the covered stent is adjusted by the stent delivery device so that the openings of the first branch 201 and the second branch 202 near the recessed portion 5 are located anterior to the opening of the brachiocephalic trunk (connected to the second indicator 703 of the first and second branches), while the opening of the third branch 203 near the second end 102 is located anterior to the opening of the left subclavian artery (connected to the second indicator 705 of the third branch), and the covered stent collapse 103 is directly opposite the supra-arc branch. Obviously, in the above process, the position of the anterior edge of the relevant blood vessel can be determined by the guide wire 8 in the corresponding branch, and the position of each embedded branch 2 can be determined by each indicator. In the above process, the covered stent does not block blood flow, and the covered stent is not attached to the blood vessel wall, so it can be easily adjusted in position and will not be displaced by the impact of blood flow. This significantly reduces the difficulty of the operation for the surgeon, the requirements for the surgeon's technical skills, and the requirements for the hardware conditions of the medical institution.

[0069] After adjustment, the core wire connecting the restraint member 6 is pulled out, thereby releasing the restraint member 6. The covered support is then fully extended, as shown. Figure 5 As shown (arrows in the diagram indicate blood flow direction), the covered stent collapse 103 is now aligned with the lesser curvature of the aortic arch. The covered stent collapse 103 and the greater curvature of the aortic arch form a cavity (recess 5). Blood flows from each embedded branch 2 into the cavity on the greater curvature side, and then into the three branch vessels above the arch, ensuring that the blood supply to the intracranial and upper limbs is not interrupted during the stent's deployment process and from deployment until the branch vessels and the stent complete branch reconstruction.

[0070] After the covered stent is installed, the guidewire 8 in the supra-arch branch vessel (such as the brachiocephalic trunk) is gently retracted until the tip of the guidewire 8 is located at the opening of the corresponding branch (such as the first branch 201), and then superselectively inserted into the corresponding embedded branch 2. A peripheral covered stent 9 of appropriate diameter and length is then advanced along the guidewire 8 to reconstruct the branch vessel, such as... Figure 6 As shown. The remaining branch vessels are reconstructed using the same method, as follows. Figure 7 and 8 As shown. During left subclavian artery reconstruction, the "upward" setting of the third branch 203 allows the axial direction of the third branch 203 to be at a suitable angle, enabling smoother connection of the corresponding peripheral covered stent 9 during reconstruction. At the same time, since the third branch 203 is located within the covered collapse 103, the distance between the left subclavian artery and the third branch 203 is closer than that of the embedded branch 2 located within the first end 101. Therefore, the guidewire 8 in the left subclavian artery can be superselectively inserted into the third branch 203 more quickly and accurately.

[0071] During the above process, each embedded branch 2 has a corresponding marker at both ends of its edge, and the two ends of the support body 1 are respectively marked with markers to indicate the edge of the support, so that the embedded branch 2 and the support body 1 can be clearly visualized under X-ray.

[0072] Successfully guiding guidewire 8 from the branch vessel into the corresponding embedded branch 2 is the key and most challenging aspect of this procedure, and also the most time-consuming part. This approach significantly reduces the difficulty of guiding guidewire 8 into the embedded branch 2, thereby drastically shortening the surgical time. Furthermore, after the covered stent is deployed, blood flow to the branch vessel is not blocked, allowing for continued normal blood supply to the supra-arch branch vessels. The limitations on surgical time are eliminated, and cardiopulmonary bypass or deep hypothermic circulatory arrest is unnecessary, thus reducing the skill requirements for the surgeon. Not blocking intracranial blood flow significantly reduces the risk of stroke, a major surgical complication of trans-arch endovascular treatment. This will promote the rapid widespread adoption of endovascular repair treatment for lesions involving the arch.

[0073] In addition, the external stent 3 can support the covered collapse 103, preventing the covered collapse 103 from adhering to the greater curvature side and obstructing the blood supply to the branch vessels after the stent body 1 is deployed. This ensures that the blood flow to the supra-arch branches is not interrupted during the reconstruction and bridging of the aforementioned branch vessels. Before the reconstruction of the branch vessels is completed, the blood flowing out from the side tube can smoothly flow into the supra-arch branch vessels without the need for intraoperative diversion. Therefore, the design of the covered collapse 103 on the greater curvature side of the stent body 1 and the external stent 3 allows sufficient time for reconstruction of the supra-arch branches during the operation. At the same time, the design of the external stent 3 prevents the embedded branch 2 within the covered collapse 103 from collapsing or becoming occluded due to compression by the stent body 1.

[0074] It should be noted that the structure of the stent delivery device, the pre-loading and delivery of the covered stent to the target position, and the technical solutions for delivering each peripheral covered stent 9 into each branch vessel for reconstruction can adopt existing technologies, and will not be repeated in this article.

[0075] Example 2

[0076] Unlike Embodiment 1, in this embodiment, all three embedded branches 2 are located within the first end 101, and correspondingly, the inner collapse platform 103 of the film does not need to be stepped.

[0077] Finally, it is necessary to state that the above embodiments are only used to further illustrate the technical solution of this utility model in detail, and should not be construed as limiting the scope of protection of this utility model. Any non-essential improvements and adjustments made by those skilled in the art based on the above content of this utility model shall fall within the scope of protection of this utility model.

Claims

1. An aortic arch stent graft, characterized by, The stent body (1) is a covered stent. The middle part of the stent body (1) is recessed from the outer wall of one side to form a recess (5). The stent body (1) has an inner covered platform (103) at the recess (5). The aortic arch covered stent also has at least one outer covered stent (3). One end of the outer covered stent (3) is suspended outside the covered platform (4) of the inner covered platform (103), and the other end is fixed to the inner covered platform (103) to prevent the inner covered platform (103) from attaching to the greater curvature of the aortic arch.

2. The aortic arch covered stent graft of claim 1, wherein, The outer support (3) of the bow is an elastic support.

3. The aortic arch covered stent of claim 1, wherein, The main body of the support (1) also includes a first end (101) and a second end (102) arranged and connected in sequence along the axial direction. The inner collapse platform (103) of the membrane is located between the first end (101) and the second end (102). The outer support (3) is fixed on the outside of the main body of the support (1). The outer part of the collapsed membrane is a large single waveform. This waveform is not fixed with the membrane and forms a semi-circular space with the collapsed membrane in the axial direction. The remaining part of the outer support (3) is a small wave multi-wave structure. It is fixed with the inner collapse platform (103) of the membrane and does not affect the bending performance of the membrane support.

4. The aortic arch endovascular stent graft according to any one of claims 1 to 3, characterized in that, The aortic arch endovascular stent graft has at least two external stents (3) arranged at axial intervals along the stent body (1).

5. The aortic arch endovascular stent graft according to any one of claims 1 to 3, characterized in that, The main body of the support (1) includes a first end (101), a membrane inner collapse platform (103), and a second end (102) arranged and connected in sequence along the axial direction. Three embedded branches (2) are provided inside the main body of the support (1). One embedded branch (2) is embedded in the membrane inner collapse platform (103), and the other two embedded branches (2) are embedded in the first end (101). The opening at the connection between the first end (101) and the membrane inner collapse platform (103) is directly opposite the recess (5) and connects the inside and outside of the main body membrane.

6. The aortic arch endovascular stent graft according to claim 5, characterized in that, The embedded branch (2) embedded in the inner collapse platform (103) of the film is inclined relative to the inner collapse platform (103). The opening of the embedded branch (2) near the second end (102) faces the recess (5) and connects the inner and outer sides of the film (4).

7. The aortic arch covered stent according to claim 6, characterized in that, The axial direction of the embedded branch (2) located in the inner collapse platform (103) of the membrane is not parallel to the axial direction of the support body (1), and the tilt angle is directed towards the second end (102).

8. The aortic arch endovascular stent graft according to any one of claims 1 to 3, characterized in that, The main body of the support (1) includes a first end (101), a membrane-covered inner collapse platform (103) and a second end (102) arranged and connected in sequence along the axial direction. The three embedded branches (2) are all located in the first end (101) on the same side of the membrane-covered inner collapse platform (103), and the openings of the three embedded branches (2) are located in the same direction but not all in the same plane.

9. The aortic arch endovascular stent graft according to any one of claims 1 to 3, characterized in that, The support body (1) is provided with a restraint (6), which restrains the support body (1) to a contracted state. Releasing the restraint (6) releases the support body (1) to an unfolded state.

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