Stent graft with pockets

Description

[0001] The present invention relates to a stent graft for implantation into vessels of a patient, comprising a hollow cylindrical base body made of a prosthetic material and at least one stent element surrounding the base body.

[0002] Such stent grafts are well known in the art, for example, through DE 103 37 739. These are vascular prostheses, also referred to as endovascular vascular stents / stent grafts, which are generally used to support unstable, brittle, or thrombotic vessel walls and, in particular, to treat aneurysmal vessels. For this purpose, a stent graft is deployed at the diseased or injured site of the vessel, restoring the functionality of the original vessel or supporting the remaining vascular integrity.

[0003] An aneurysm is defined as a dilation or bulging of an arterial blood vessel resulting from congenital or acquired changes in its wall. The bulging can involve the entire vessel wall, or, as in a so-called false aneurysm or dissection, blood leaks from the lumen of the vessel between the layers of the vessel wall and shears them apart. If an aneurysm is left untreated, it can lead to a rupture of the artery in advanced stages, resulting in internal bleeding. Thoracic and thoracoabdominal aortic aneurysms can be caused by arteriosclerosis, high blood pressure, and inflammation of the vessel wall. Injuries to the chest caused by serious accidents can also lead to an acute or chronic aortic aneurysm.

[0004] Depending on the application, a wide variety of stent grafts are used. A distinction is made between balloon-expandable and self-expanding systems. Self-expanding properties arise from the use of self-expanding materials, such as nitinol. Balloon-expandable systems are expanded by a radial force applied from the inside, for example, when mounted on a balloon.

[0005] The present application deals with the application of so-called self-expanding stent grafts or "covered" stents.

[0006] To treat aneurysms or vessels at risk of occlusion, it is already known to stabilize the affected blood vessels by implanting a stent / stent graft to prevent rupture or generally ensure that the vessel remains open. The self-expanding stent grafts used generally consist of a hollow cylindrical metal frame or scaffold, the outer surface of which is covered with a textile or polymer film, creating a hollow cylindrical body. The biocompatibility of the materials used ensures complication-free contact between the expanded stent graft and the vessel wall.

[0007] Another function of the textile or polymer film is to prevent blood, blood components, or deposits from passing through the stent graft wall, as well as tissue ingrowth through the wall into the interior of the stent graft. This relieves pressure on the vessel wall at the stent graft implantation site and prevents possible embolisms at these sites.

[0008] The metal frame of such stent grafts typically consists of a wire mesh or of sequentially arranged, meandering, so-called stent springs, which may be connected to each other via wire connecting supports or simply via the prosthetic material. The wire mesh or stent springs are usually made of a shape-memory material, usually nitinol, which allows the stent springs to return to their expanded state after being inserted into a vessel for release, thus "stretching" the stent graft.

[0009] During implantation, the stent is compressed radially, significantly reducing its cross-sectional area. To achieve the compressed state, the stent graft is inserted into a sheath known as a sheath catheter. The sheath catheter has a circumference that is smaller than the circumference of the stent graft in its expanded state. The stent graft is delivered in its compressed state using a delivery system to the area to be treated or the aneurysm, where it is released. The position of the stent graft can be monitored using X-ray markers. Once the desired position or orientation of the stent graft has been achieved, the sheath catheter is withdrawn, releasing the stent graft and allowing it to expand.Due to the spring action of the metal frame / scaffold, the stent graft expands back to its original shape, stretching its outer surface, which clamps itself inside the blood vessel proximal and distal to the aneurysm or the area to be kept open. The compressive force between the stent graft and the vessel wall keeps the stent graft in place. This allows blood to flow through the stent graft, preventing further stress on the aneurysm and ensuring that the vessel remains open.

[0010] When positioning the stent grafts, the blood supply to the lateral blood vessels branching off from the main vessel must not be cut off by the blood-tight prosthetic material. Therefore, many stent grafts feature open zones or so-called fenestrations in the sheath or prosthetic material, through which side branches branching off from the stent graft and extending into the lateral vessels can be introduced and secured to the stent graft. This also ensures blood supply to the areas of the body supplied by the lateral vessels.

[0011] Due to the fact that the properties depend on both the vessels to be treated and the individual patient, it certainly makes sense to produce custom-made stent grafts based on the anatomy of the specific vessel. However, this is not only complex in terms of the individual design of the scale, length, and width, but also the actual production of the stents is very complex, expensive, and labor-intensive, as in certain cases, only one specific prosthesis can be manufactured.

[0012] During the production of stent grafts, especially those with meandering stent springs that are only indirectly connected to each other via the implant material, the outer surfaces are manually sewn to the metal frame / scaffold by specialists, which is very time-consuming and costly.

[0013] US 2007 / 0219622 A1, WO 2016 / 183128 A1, US 5,123,917 and US 5,843,166 each disclose a stent graft consisting of two prosthetic material tubes arranged one above the other, by means of which pockets are formed.

[0014] There is therefore still a great need for stent / stent graft systems or vascular prostheses that enable flexible use in order to meet the different requirements - especially with regard to the individual design - of the respective vessels of different patients.

[0015] The object of the present invention is therefore to provide an alternative stent graft with which the above-described disadvantages of the stent grafts known in the prior art can be overcome and with which the production is less time-consuming and cost-intensive.

[0016] According to the invention, the above-mentioned and other objects are achieved by a stent graft for implantation into vessels, in particular blood vessels, of a patient according to claim 1, wherein the stent graft comprises: a hollow cylindrical base body made of a first prosthetic material, having a proximal and a distal end, with a longitudinal axis c and a circumference u, at least one pocket element made of a second prosthetic material, which is circumferentially attached to the outer and / or inner side of the base body to form a circumferential closed pocket on a longitudinal section of the base body, and at least one stent element meandering around the base body and received within the pocket element, wherein the at least one pocket element is shorter than the base body and has a proximal and a distal end as well as a main section located therebetween,wherein the at least one pocket element for forming the closed pocket is attached circumferentially to the outside and / or inside of the base body only via its respective distal and proximal ends, and the main section is not attached to the base body, and wherein between 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25 or 30 pocket elements are provided, which are fixed at a distance x and separately from one another on the base body.

[0017] The problem underlying the invention is thereby completely solved.

[0018] The stent graft according to the invention provides a vascular prosthesis that can be used to support unstable, brittle, or thrombic vessel walls and, in particular, to treat aneurysmal vessels. This is achieved through the special structure of the stent graft, which is based on a hollow-cylindrical base body made of a first prosthetic material and stent elements. The stent elements are not directly attached to the base body—e.g., via sutures—but rather are located in closed pocket elements provided externally or internally on the base body, and are thus practically "free" within them, i.e., not fixed by sutures. The stent elements are therefore only attached to the base body "indirectly" (= not fixed by sutures) by being incorporated into the pocket elements.

[0019] According to a preferred embodiment, the stent graft according to the invention is a self-expanding stent graft.

[0020] The stent graft according to the invention has the advantage that, by providing pocket elements and simply accommodating the stent elements within the pocket elements, the individual stent elements do not need to be laboriously and individually fixed to the base body with numerous sutures. This significantly simplifies production, while maintaining the basic technical function of the stent graft or stent elements. Thus, production is less time-consuming and cost-intensive. Due to the special design of the stent graft according to the invention, for example, the manual sewing of the stent elements can be replaced by machine-made sutures that form the pockets in which the stent elements are located. According to an alternative embodiment, the pockets can also be glued or welded into the prosthetic material.

[0021] The pocket elements containing the stent elements can be mounted either internally or externally with respect to the hollow cylindrical base body. This means that the base body forms an outer shell if the pocket elements are located inside. Conversely, the base body forms an inner shell if the pocket elements are located outside. In another embodiment, it may be advantageous to mount the pocket elements both internally and externally.

[0022] The simple manufacturing possibility of the stent graft according to the invention not only makes it possible to produce individual stent grafts adapted to individual patients to be treated, but also to prefabricate universally applicable stent grafts.

[0023] According to the invention, the stent elements serve not only to provide the stent graft with the necessary structure, but also to press the stent graft against the vessel wall when implanted, thus holding it in position within the vessel. The properties of the stent elements used depend on the vessel being treated. For example, in a very thin-walled vessel, it is advantageous to use stent grafts that are less rigid and have fewer stent elements overall.

[0024] The special structure of the stent graft according to the invention also results in the advantage that both outside and inside only the prosthetic material is present, which is preferably biocompatible.

[0025] Because the stent elements are housed in closed pocket elements, mechanical damage or irritation of the vessel walls caused by stent elements that would otherwise be exposed is also avoided.

[0026] In this case, "base body" refers to the main body of the hollow cylindrical stent graft, which consists of a first prosthetic material.

[0027] According to the invention, the at least one pocket element is shorter than the base body and has a proximal and a distal end as well as a main section located therebetween, wherein the at least one pocket element is fastened circumferentially on the outside and / or inside of the base body only via its respective distal and proximal end to form the closed pocket and the main section is not fastened to the base body.

[0028] According to the invention, at least one pocket element is located on the base body, the length of which is preferably adapted to the dimensions of the stent element to be inserted.

[0029] According to the invention, between 1 and 30 pocket elements are provided, which are fixed at a distance and separately from one another on the base body.

[0030] The stent graft according to the invention preferably has between 3 and 25, more preferably between 5 and 20 pocket elements. Accordingly, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, or 30 pocket elements are provided for the corresponding number of stent elements, which are distributed along the longitudinal axis of the base body and spaced apart from one another. The length of the pocket elements—relative to the longitudinal axis—is always shorter than the length of the base body and adapted to the dimensions of the stent elements.

[0031] It is also conceivable to provide pocket elements of different lengths that accommodate different stent elements.

[0032] In the section(s) where the pocket elements are located, two layers of prosthetic material are stacked on top of each other, with one layer being the prosthetic material of the base body and the other layer being the prosthetic material of the pocket element. The pocket element is attached circumferentially to the base body at both its distal and proximal ends.

[0033] In this context, "meandering" means any loop-like or loop-like course of a stent element.

[0034] Generally, the terms "distal" and "proximal" are used to refer to the respective ends of stent grafts. "Distal" refers to the part or end that is further downstream in relation to the bloodstream. "Proximal," on the other hand, refers to a part or end that is further upstream in relation to the bloodstream. In other words, "distal" means in the direction of bloodflow, and "proximal" means opposite to the direction of bloodflow. For catheters or delivery systems, however, the term "distal" refers to the end of the catheter or delivery system that is inserted into the patient, or the end that is furthest from the user's perspective, and "proximal" refers to the end closest to the user.

[0035] According to the invention, the division of the main body of the self-expanding stent graft into proximal end section and distal end section means that the respective sections can be distinguished from one another by a different construction.

[0036] For example, a different number of stent elements and thus also pocket elements can be present in the sections of the base body. In other words, one embodiment can provide that if there are multiple pocket elements and stent elements, these—i.e., the pocket elements—are not evenly distributed along the longitudinal axis of the base body. The stent elements accommodated in the pocket elements can also have different diameters, which can lead to different diameters of the base body.

[0037] For the purposes of this document, "stent" or "stent element" refers to any structure that provides expansion force and / or a supportive function to a vascular prosthesis. Accordingly, a stent element is any element that exhibits the properties of a stent.

[0038] The term "stent graft" is intended here—as in the prior art—to mean a vascular prosthesis comprising one or more stent elements (or stent springs) and a prosthetic ("graft") material indirectly or directly connected thereto to form a lumen through at least a portion of the stent graft. Such a stent graft is also referred to as a covered stent.

[0039] According to one embodiment, the pocket elements, or their ends fixed to the base body, are not directly connected to each other.

[0040] According to another embodiment, the ends of the pocket elements are provided directly adjacent to the ends of a proximal or distally arranged pocket element.

[0041] Depending on the application, it is advantageous if the stent graft according to the invention has several pocket elements and stent elements contained therein. The number of stent elements will depend, among other things, on the length of the required stent graft. Since the length of the stent graft is preferably between 5 and 300 cm, preferably between 8 and 26 cm, the preferred number of prosthetic material elements is 1 to 30, preferably between 2 and 15.

[0042] The number of pocket elements determines the desired structure and properties of the stent graft. For example, the presence of several stent elements positioned closely behind one another results in a less flexible vascular prosthesis than one with fewer stent elements.

[0043] For the treatment of particularly thin-walled or sensitive vessels, it can be advantageous to have a continuous change in the density of the stent elements within the stent graft. For example, it can be advantageous to have a particularly large number of stent elements in the proximal region of the stent graft, while the number of stent elements decreases in the distal direction. This results in increasing softness of the stent graft from the proximal to the distal end, or conversely, a continuous increase in stiffness of the stent graft from the distal end to the proximal end.

[0044] In addition to the stent elements, it is also preferable that the diameter is adapted to the specific vessel to be treated. According to the invention, the stent graft or the base body of the stent graft can thus have a uniform diameter over its entire length, or it can have different diameters. The diameter of the stent graft is determined by the stent elements and the hollow cylindrical base body.

[0045] According to one embodiment of the stent graft according to the invention, the pocket elements are fixed to the base body at a distance x of 1 mm to 30 mm, preferably between 2 mm and 15 mm.

[0046] By varying the distance x from 1 mm to 30 mm, preferably between 2 mm and 15 mm, the stent graft can be advantageously adapted to the specific application and thus to the corresponding vessel. For example, a very wide spacing of the pocket elements can result in a more flexible stent graft than one in which the pocket elements are spaced closer together.

[0047] In a further development of the stent graft according to the invention, the stent element has or consists of a one-piece stent spring which has pointed arches pointing alternately towards the proximal and distal end of the base body and parallel to its longitudinal axis c, wherein a pointed arch is formed from one vertex and two legs, wherein the legs have different or equal lengths.

[0048] In this context, a "stent spring" is defined as any one-piece, annular element that, due to its material, can be compressed and then expanded again in a spring-like manner after the compression pressure is removed. Stent springs exhibit a wave-like orbit, with wave crests and troughs forming a single phase and alternating with each other.

[0049] The stent elements or stent springs can have the same or different circumferential amplitudes, resulting from the equal or different lengths of the stent springs. Different amplitudes offer the advantage that the stent graft can be adapted to the specific vessel and its specific characteristics (curvatures, branching vessels, tapers, etc.).

[0050] According to the invention, the stent elements can also comprise braided, twisted or laser-cut stent elements instead of the individual stent springs.

[0051] According to the invention, the stent element is enclosed within the pocket elements and is movable, and is therefore not directly and immediately fixed to the first prosthetic material by sutures or otherwise.

[0052] According to a further embodiment of the stent graft according to the invention, a single stent element is accommodated within a pocket element.

[0053] Due to the design of the stent graft according to the invention, the pocket elements are designed in such a way that the freedom of movement of the stent elements within the pocket elements is severely restricted, preferably to the point of immobility, due to the size of the pocket elements and the resulting tension of the prosthetic material forming them. Thus, the stent elements can be advantageously inserted into the pocket elements in such a way that no unwanted kinks or prosthetic material bulges or material accumulation occur when the stent graft is bent.

[0054] Depending on the application, and according to another embodiment, individual stent elements may not be fixed in pocket elements on the base body, but may be additionally fixed to the base body, for example, via a suture inside or outside. It will be clear to those skilled in the art that the design of the stent graft depends on the characteristics of the particular vessels to be treated with the stent graft according to the invention.

[0055] In particular, it is preferred if a stent element is present at the distal and / or proximal end of the base body, which is attached directly to the first prosthetic material of the base body - e.g. via sutures.

[0056] According to a further embodiment, a stent element attached to the proximal end of the stent graft is attached to the first prosthetic material only via its distally facing ogive arches, but not via its proximally facing ogive arches. According to a further embodiment, a stent element attached to the distal end of the stent graft is attached to the first prosthetic material only via its proximally facing ogive arches.

[0057] In a preferred embodiment of the stent graft, the pocket element is sewn to the hollow cylindrical base body, for example, by a circumferential suture.

[0058] According to the invention, the circumferential seam delimits the pocket in which the stent elements are located. The seam is preferably designed such that the stent elements can be inserted into the formed pockets. Advantageously, the circumferential seam can be machined, for example, thus saving time and associated costs in the manufacture of the stent graft. To create the pockets, one end of the pocket element is first sewn circumferentially or otherwise secured to the base body. The stent element is then inserted into the still-open pocket, and the pocket element is closed by sewing or otherwise securing the second end of the pocket element.

[0059] Surgical thread is preferably used as the suture material. This thread is preferably made of polyester, polyurethane, polystyrene, polytetrafluoroethylene, ultra-high molecular weight polyethylene (UHMPE), or mixtures thereof.

[0060] In addition to fixing the pocket element to the base body by a seam, the invention also allows for fastening by gluing, fusing or welding.

[0061] In a further preferred embodiment of the stent graft, the at least one pocket element and the stent element have substantially the same height relative to the longitudinal axis c.

[0062] Here, as in the present case, "essentially" means that the pocket element and the stent element do not have exactly the same height, but that approximately the same height is also possible. This embodiment has the advantage that the stent element is virtually immobile due to the predetermined pocket height. Thus, the pocket, due to its dimensions, fixes the stent element in place.

[0063] In a preferred embodiment of the stent graft, the stent graft has at least one side branch branching inwards or outwards from the hollow cylindrical base body, which extends distally parallel to the longitudinal axis of the hollow cylindrical base body.

[0064] In this case, "at least one branching side branch" preferably means one, two, three or four side branches.

[0065] With the side branch, the outer surface of the base body has one or at least one opening, which reliably ensures the supply of the outgoing side vessels via the vascular prosthesis side branches. This is necessary when using the stent graft within vessels that have side vessels. It will be clear to those skilled in the art that this depends on the specific characteristics of the vessels to be treated with the stent graft according to the invention.

[0066] This design therefore offers the advantage that it can be adapted to the respective anatomical conditions of the patient to be treated.

[0067] In a preferred embodiment of the stent graft, a marker containing a radiopaque material or consisting entirely of radiopaque material is located on the stent graft.

[0068] With the help of markers located on specific areas of the stent graft, it is possible to quickly determine the exact position of the stent graft during and after implantation.

[0069] Preferably, the radiopaque markers are made of one or more of the following materials, e.g., gold, palladium, tantalum, chromium, silver, etc.; the shape of the markers can be arbitrary, e.g., round or square, and / or, for example, in the form of letters, numbers, or figures that are helpful for orienting the stent graft in the vessel.

[0070] In a further preferred embodiment of the stent graft, the at least one stent element comprises or is formed from nitinol and can be converted from a non-expanded state to a self-expanded state.

[0071] By using the self-expanding material Nitinol, the stent elements have shape memory properties.

[0072] In a preferred embodiment of the stent graft, the first and / or the second prosthetic material comprises a material selected from a textile or a polymer.

[0073] In particular, it is preferred if the first and / or second prosthetic material comprises or is formed from a material selected from polyester, polyurethane, polystyrene, polytetrafluoroethylene, ultra-high molecular weight polyethylene (UHMPE), or mixtures thereof.

[0074] In a further preferred embodiment, the first and second prosthetic material are made of the same material, or at least partially comprise different materials.

[0075] According to a further embodiment, the stent graft according to the invention, as mentioned above, is to be used for the treatment of dissection diseases or aneurysmal diseases of the blood vessels.

[0076] Furthermore, the present invention also relates to a method for releasing the stent graft according to the invention.

[0077] Further advantages emerge from the figures and the following description of preferred embodiments.

[0078] It is understood that the features mentioned above and those to be explained below can be used not only in the combination specified in each case, but also in other combinations or on their own, without departing from the scope of the present invention.

[0079] Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description. They show: Fig. 1 a schematic representation of an embodiment of a stent graft according to the invention, in the non-introduced, expanded state in a perspective view of the long side from above; Fig. 2 a section of the embodiment from Fig.1 , which is shown as a cross-section along the longitudinal axis c from above; Fig. 3 another schematic representation of a section of the embodiment of a stent graft according to the invention, in full lateral view of the long side, in perspective view of the long side from above; Fig. 4 a schematic representation of a section of the embodiment of a stent graft according to the invention, which is provided with a side branch, shown in a perspective view from above; and Fig. 5a further schematic representation of a section of the embodiment of a stent graft according to the invention, wherein the proximal end has a partially free stent spring, in a perspective view of the long side from above.

[0080] In the figures, identical features are provided with identical reference symbols, although for reasons of clarity not all reference symbols are always indicated in all figures.

[0081] As can be seen from the Figures 1 to 5As can be seen, the self-expanding stent graft 10 comprises a hollow cylindrical base body 11 made of a first prosthetic material (graft) 12 with a longitudinal axis c 13 and a circumference u 14. The stent graft 10 also has a distal and a proximal opening 15, 16. The base body 11 forms a jacket to which hollow cylindrical pocket elements 17 made of a second prosthetic material 12 are attached by seams 18. In this case, a closed pocket 17 is formed into which the stent elements 19 are received. The stent elements 19 are preferably stent springs. In addition to the stent springs, braided, twisted or laser-cut stent elements 19 can also be used as stent elements 19 (not shown), provided they have self-expanding properties.

[0082] The structure, or rather the quality, of the stent graft 10 is largely determined by the structure of the base body 11 and by the surrounding stent elements 19. While the base body 11 determines the size, or rather the spatial dimensions, the stent elements 19 determine the self-expanding properties as well as the quality (e.g., the flexibility) of the stent graft 10.

[0083] In the Figures 1 and 3 to 5 The arrow "d" indicates the distal direction 20, and the arrow "p" the proximal direction 21. In Fig. 1 The longitudinal axis 13, indicated by a double arrow, is designated by the letter "c." The circumference 14, which refers to the base body 11, is designated by the letter "u."

[0084] As can be seen in all figures, the pocket elements 17 are preferably attached to the base body 11 by seams 18. In a manner not shown, the attachment can also be achieved by gluing, fusing, etc.

[0085] The pocket elements 17 made of the second prosthetic material 12 are designed such that the stent elements 19 fit optimally into their cavity, so that they are fixed within the pockets 17 due to the tension of the prosthetic material 12 and are thus almost immobile.

[0086] As in the Figures 1 to 5 As can be seen, the base body 11 forms an inner shell. In an alternative embodiment (not shown), the base body 11 can also form an outer shell, in the interior of which the pocket-forming pocket elements 17 are fastened. In a further alternative embodiment (not shown), the pockets 17 can be located both internally and externally with respect to the base body 11.

[0087] The stent elements 19 are preferably stent springs that meander around the base body 11. As Figures 3 to 5 As can be seen, the stent springs are not necessarily identical in size and shape.

[0088] According to the invention, the stent springs are located within the pockets 17. Alternatively or additionally, individual stent springs can also be attached directly inside or outside the base body 11, preferably by means of a seam 18, as also shown in the Figure 5 is evident.

[0089] Essentially, the stent graft 10 has a constant diameter along the longitudinal axis 13. However, this depends on the particular blood vessel to be treated, into which the stent graft 10 is to be implanted. As can be seen in particular from Fig. 3As can be seen, the proximal end 16 can have a larger circumference 14 than the distal end 15. This results in a continuous taper in the distal direction 20. The different circumference 14 resulting along the longitudinal axis 13 is achieved both by the base body 11 itself and by the surrounding stent springs. Thus, the stent springs in the proximal direction 21 have a larger diameter than those in the distal direction 20. A continuous change in the circumference 14 preferably results from both the stent springs and the base body 11. This is intended to avoid or prevent any accumulation of material as well as prosthetic material beads.

[0090] Fig.3shows that the base body 11 obtains its hollow cylindrical shape through a seam 18 along the longitudinal axis c 13. A seam 18 is not absolutely necessary; alternatively, the base body 11 can already consist of a hollow cylindrical prosthetic material 12.

[0091] Fig.4 It can also be seen that the stent graft 10 comprises a side branch 22. This is mounted such that it extends inward, into the interior, i.e., into the lumen of the main body 11. Thus, the side branch 22 has a first opening, which is firmly attached in the prosthetic material 12 of the main body 11 (within the section x), and a second opening, which extends into the lumen of the main body 11.

[0092] The side branch 22 has a stent element 19 located in the region of the second opening, which keeps this opening open. The stent element 19, together with the prosthetic material 12, forms the side branch 22. The side branch 22 is therefore another, smaller stent graft, which is fixed to the actual stent graft 10.

[0093] The stent element, which meanders around the side branch 22, can be attached directly to the prosthetic material 12 by sutures 18, or can be located in pockets 17 made of prosthetic material 12, analogous to the stent elements 19, which are attached around the base body 11.

[0094] The size of the side branches 22 is adapted to the respective blood vessel to be treated. According to the invention, the stent graft 10 is not limited to one side branch 22; rather, the number of side branches 22 depends on the characteristics of the vessels present in the patient.

[0095] As can be seen from the Figures 4 and 5 As can be seen, the stent graft 10 has X-ray markers 24 at specific locations. The radiopaque markers 24 are located at the distal end 15 as well as around the opening of the side branch 22. The markers 24 are necessary to ensure correct positioning within the vessel during implantation. The attending physician can thus quickly and accurately determine the exact position of the stent graft 10 within the vessel using X-ray control and, if necessary, correct it during implantation.

[0096] On the one hand, the base body 11, as in Fig. 1 shown, form the proximal and distal ends of the stent graft 10. On the other hand, one end of the stent graft 10 can also end with a pocket element 17 (not shown). Another possible embodiment of the proximal end of the stent graft 10 is shown in Fig. 5shown, in which a stent spring at the proximal end 16 is only partially attached to the base body 11 of the prosthetic material 12, preferably by means of a suture 18.

[0097] To introduce the stent graft 10 according to the invention, the stent graft 10 is loaded onto a delivery system (not shown) and held in a compressed state by a corresponding sheath (not shown). Methods and devices for introducing stent grafts 10 are familiar to those skilled in the art.

[0098] First, the compressed stent graft 10 is advanced into the vessel to be treated. Correct placement can be monitored, for example, using appropriate markers 24 provided on the stent graft 10 – e.g., radiopaque markers. After correct placement, the stent graft 10 can now be released by retracting a sheath or similar device that keeps the stent graft 10 compressed.

Claims

1. A stent graft (10) for implantation in vessels of a patient, wherein the stent graft (10) has the following: a hollow-cylindrical body (11) made of a first prosthesis material (12), with a proximal end and a distal end, and with a longitudinal axis c (13) and a circumference u (14), at least one pocket element (17), which is made of a second prosthesis material (12) and which is mounted circumferentially on the outer and / or inner face of the body (11) in order to form a circumferential closed pocket (17) on a longitudinal portion of the body (11), and at least one stent element (19), which extends in a meandering formation around the body (11) and is received inside the pocket element (17), wherein the at least one pocket element (17) is shorter than the body (11) and has a proximal end and a distal end and, positioned between these, a main portion (23), wherein the at least one pocket element (17) for forming the closed pocket (17) is circumferentially secured only via its respective distal and proximal end to the outside and / or inside of the body (11), and the main portion (23) is not secured to the body (11), characterized in that 2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20, 25 or 30 pocket elements (17) are provided, which are fixed at a distance from each other and separate from each other on the body (11).

2. The stent graft (10) as claimed in claim 1, characterized in that the pocket elements (17) are fixed at a distance of 1 mm to 30 mm on the body (11).

3. The stent graft (10) as claimed in one of claims 1 or 2, characterized in that the stent element (19) has or consists of a one-piece stent spring, with pointed arches facing alternately to the proximal and distal end of the body (11) and parallel to the longitudinal axis c (13) of the latter, wherein a pointed arch is formed in each case from a vertex and two legs, wherein the legs have different or identical lengths.

4. The stent graft (10) as claimed in one of claims 1 through 3, characterized in that an individual stent element (19) is received inside a pocket element (17).

5. The stent graft (10) as claimed in one of claims 1 through 4, characterized in that the pocket element (17) is sewn onto the hollow-cylindrical body (11).

6. The stent graft (10) as claimed in one of claims 1 through 5, characterized in that the pocket element (17) and the stent element (19) have substantially the same height, relative to the longitudinal axis c (13).

7. The stent graft (10) as claimed in one of claims 1 through 6, characterized in that it has at least one side branch (22) branching off inwardly or outwardly from the hollow-cylindrical body (11) and extending in the distal direction parallel to the longitudinal axis (13) of the hollow-cylindrical body (11).

8. The stent graft (10) as claimed in one of claims 1 through 7, characterized in that a marker (24) is located on the stent graft (10), which marker (24) contains a radiopaque material or is made entirely of radiopaque material.

9. The stent graft (10) as claimed in one of claims 1 through 8, characterized in that the at least one stent element (19) comprises or is formed from nitinol and can be converted from a non-expanded state to a self-expanded state.

10. The stent graft (10) as claimed in one of claims 1 through 9, characterized in that the first and / or second prosthesis material (12) comprises a material that is chosen from a textile or a polymer.

11. The stent graft (10) as claimed in one of claims 1 through 10, characterized in that the first and / or second prosthesis material (12) comprises or is formed from a material that is chosen from polyester, polyurethane, polystyrene, polytetrafluoroethylene, ultra-high molecular weight polyethylene (UHMPE), or mixtures thereof.

12. The stent graft (10) as claimed in one of claims 1 through 11, characterized in that the first and second prosthesis materials (12) are the same material or at least partially different materials.