IMPLANT WITH A THREE-DIMENSIONAL STRUCTURE

Description

[0001] The present application relates to a tubular perforated structure for a catheter sleeve or for an implant, which extends in a longitudinal or circumferential direction and is composed of a plurality of webs that extend at least partially in the longitudinal or circumferential direction. The invention further relates to a corresponding catheter sleeve, a corresponding implant, and a corresponding catheter.

[0002] A wide variety of medical implants, particularly intraluminal endoprostheses, for a wide variety of applications are known from the prior art. Implants within the meaning of the present invention are understood to mean endovascular prostheses or other endoprostheses, for example, stents (vascular stents, including stents for use in the heart and heart valve stents, for example, mitral valve stents, pulmonary valve stents) and bile duct stents), endoprostheses for closing patent foramen ovale (PFO), stent grafts for treating aneurysms, endoprostheses for closing an atrial septal defect (ASD), and prostheses in the area of ​​hard and soft tissue.

[0003] Such an implant usually has two states: a compressed state with a small diameter and an expanded state with a larger diameter. In the compressed state, the implant can be inserted into the vessel or organ to be treated using a catheter through narrow vessels and positioned at the site to be treated. In the expanded state, the implant remains in the vessel or organ and is fixed there after the catheter has been removed from the patient's body. For example, in transcatheter aortic valve implantation (endovascular aortic valve replacement, or transcatheter aortic valve implantation, TAVI), an artificial aortic valve is inserted into the heart in a tubular scaffold. The valve is moved into position using a catheter. It is then unfolded and anchored.The body's own aortic valve is not removed, but rather displaced by the implant. With a self-expanding implant made of a shape memory alloy, the implant automatically expands when a certain transition temperature is exceeded or a certain tension is applied. For an implant with a balloon-expandable base frame (stent), a balloon is required for this purpose.

[0004] From the publication US 2008 / 0188928 A1, a catheter for releasing a heart valve implant is known. The catheter has a capsule sleeve for transporting the folded heart valve implant through the patient's vessels. The capsule sleeve is flexible, allowing it to be guided through the tortuous vessels, and is suitable for receiving and holding the implant and enabling its release at the treatment site. The sleeve is composed of an inner polymer layer and an outer polymer layer, between which one or more support elements with variable axial stiffness are arranged. A tubular support element is formed, for example, from a plurality of rings or ribs arranged side by side in the longitudinal direction. All ribs are connected by a longitudinally extending web.

[0005] The publications EP 2 591 751 A1, EP 2 679 198 A1, and US 2010 / 0249905 A1 show implants with various perforated tubular structures. The publication EP 2 679 198 A1 describes a stent for a heart valve implant consisting of a wire structure with several sections arranged longitudinally next to one another, each of which differs in structure and properties and is interconnected. In contrast, the publication US 2010 / 0249905 A1 describes a tubular implant with a plurality of webs connected by inclined, flexible connectors. The webs and connectors have openings filled with a drug for release at the site of the body into which the implant is inserted.

[0006] EP 2 591 751 A1 describes an endoluminal prosthesis system for a branched body lumen comprising a vascular prosthesis (11). The vascular prosthesis (11) is deployable within a branched vessel lumen and includes a stent (48) with a generally tubular body portion (33), an expandable proximal end portion (36), and a coupling portion (38) disposed between the body portion and the expandable portion. The coupling portion is preferably more crush-resistant than the body portion.

[0007] These days, catheters made of plastic or composites are predominantly used to implant stent-supported heart valve implants; their bendability and flexibility are limited. During implantation and positioning of the heart valve implant, it is released from a catheter sleeve (also known as a capsule), which held the implant in a compressed state during transport through the patient's vessels. Such heart valve implants consist of a framework designed like a stent, which carries the actual valve material. This framework or stent is self-expanding, e.g. made of a shape memory material such as nitinol, and is held in its compressed state by the catheter sleeve. Through relative movement of the catheter sleeve to the self-expanding heart valve implant, the compressing force is removed and the self-expanding stent orThe scaffold, and thus the entire heart valve implant, changes from a compressed state to an expanded state. However, the implant must also be partially retracted into the catheter sleeve to allow for repositioning.

[0008] Particularly with self-expanding heart valve implants, strong radial and axial forces occur during deployment and retraction of the implant into the catheter sleeve, which depend on the stiffness of the implant. These reaction forces can lead to permanent deformation of the catheter sleeve, which can cause vascular injuries and related complications when the catheter and catheter sleeve are removed from the patient's body. Greater flexural flexibility is also desirable for implants.

[0009] The object of the present invention is therefore to provide a structure which is flexible in the radial direction and at the same time enables the transmission of strong radial and axial, ie longitudinal, compressive forces.

[0010] The above object is achieved by the structure having the features of claim 1. Respectively, the object is achieved by the implant comprising said structure according to claim 1.

[0011] According to the invention, the tubular perforated structure for a catheter sleeve or for an implant with a plurality of webs extending at least partially in the longitudinal or circumferential direction comprises at least one joint element, the longitudinally extending main web of which has a continuous gap (separation). Furthermore, at least one bridge web, preferably two bridge webs, is / are provided on the joint element, wherein each bridge web is arranged circumferentially adjacent to the main web and is connected to the main web in front of and behind the gap in the longitudinal direction.

[0012] In the region of the gap, the main web is completely severed. The gap is preferably located approximately in the middle of the joint element. The bridge web(s) act as connectors and prevent the main web from drifting apart under slight tensile forces. The joint element is connected to the webs of the structure, preferably - viewed in the longitudinal direction - at both ends to a longitudinally extending web of the structure, particularly preferably in the region where the bridge web(s) are connected to the main web. In a particularly preferred embodiment, this connecting web forms the continuation of the main web in the longitudinal direction.

[0013] For the purposes of the present invention, longitudinally extending webs are understood to mean webs that run both exactly parallel and at a small angle to the longitudinal direction of the structure. When the structure, located on the circumference of the tube, rolls into a plane, the angle between the web and the longitudinal direction is a maximum of 0-45°. The longitudinal direction of a structure, such as a substantially cylindrical implant or catheter sleeve, corresponds to the cylinder axis of the cylindrical implant structure or the catheter axis in the case of a catheter sleeve.

[0014] The joint element according to the invention is a structure whose properties can be compared to a flexural joint and, similar to human joints, can transmit compressive forces, but also allows sliding in the region of the gap arranged in the main web, as well as rotation of the opposite ends of the main web in the gap relative to each other. Therefore, the joint element has a high degree of flexural flexibility. The joint element is also capable of transmitting compressive forces in the longitudinal or radial direction. This occurs, on the one hand, via the bridge webs. On the other hand, when a predetermined axial pressure is exceeded, the ends of the main web forming the gap are pressed together until they abut one another. The pressure is then transmitted not only via the bridge web(s), but also via the main web.The joint element according to the invention, which is preferably present in multiple parts within the structure, provides the structure with the desired flexural flexibility, allowing it to transmit even large radial and axial compressive forces. In stent implants, the joint structure can also be used at the circumferential bar intersections. This gives the stent great flexural flexibility, which facilitates adaptation to anatomical structures such as calcifications. The radial force can thus be transmitted via the closing joints, while at the same time the stent maintains high flexibility (low crush resistance) in the circumferential direction, which is necessary for particularly adaptable structures.

[0015] In a preferred embodiment, the bridge web is semicircular, U-shaped, V-shaped, or meander-shaped. The different shapes of the bridge webs allow adaptation to the varying bending flexibility required by the structure, depending on the use of the structure. In a further embodiment, the bridge webs can have additional spring elements or changes in the cross-section. Greater bending flexibility can be achieved by providing the bridge web with at least one notch section with a notch running transversely to the longitudinal direction. Such a notch section can be formed as a U-, V-, or W-shaped section. Alternatively, the bridge web can only have an area with a reduced width or thickness in the section.

[0016] It is advantageous if the gap has a width of at least 20 µm, preferably at least 40 µm to 500 µm, depending on the application. The gap width is measured along the longitudinal axis (i.e., in the longitudinal direction) of the tubular structure. This ensures the desired increased bending flexibility.

[0017] It is also advantageous for the bending flexibility of the joint element if the bridge web has a width of 20% to 40% of the main web width. In designs with more than one bridge web, the width of the bridge webs is selected such that it does not exceed the width of the main web. Accordingly, in a design with two bridge webs, these preferably each have a width of 20% to 50% of the main web width. In a design with only one bridge web, this has a width of 20% to 100% of the main web. The width is measured perpendicular to the center line of the respective web.

[0018] Bending flexibility in any radial direction is ensured when the structure has a plurality of joint elements arranged next to one another in the circumferential direction. Particularly preferably, the plurality of joint elements is provided along the entire circumference of the structure, so that a funnel-shaped radial expansion of the structure is realized, for example when releasing a self-expanding implant. With regard to a catheter sleeve, it is particularly advantageous if a section with a plurality of joint elements arranged next to one another in the circumferential direction forms a distal section of the catheter sleeve, because increased bending flexibility is required in this region, particularly in the distal section of the catheter sleeve, for the release and retraction of, for example, a heart valve implant from / into the catheter.Particularly preferably, at least two such sections with the plurality of joint elements are provided one behind the other in the longitudinal direction. The joint elements can be designed such that their flexibility decreases in the proximal direction, for example by reinforcing the bridge webs. In a preferred embodiment of the structure according to the invention, a section is provided in the longitudinal direction adjacent to the section with the plurality of joint elements arranged next to one another, in which section one or more wave-shaped webs are arranged, which particularly preferably run around the entire circumference. These webs can absorb the forces transmitted by the joint elements. This prevents deformation of the catheter sleeve, which can be problematic when the catheter is removed from the body.

[0019] In one embodiment of the present invention, it is advantageous if the structure according to the invention consists of or comprises a shape memory alloy, in particular nitinol. A structure according to the invention made of polymer, a cobalt-chromium alloy (CoCr), or steel may also be useful in certain embodiments.

[0020] The above object is also achieved by an implant, in particular a stent, which has the above-described tubular, perforated structure according to the invention in at least one section. In this section, the implant has the described bending flexibility, whereby high compressive forces can also be transmitted in the radial and axial directions. According to the invention, the implant can also consist entirely of the described tubular, perforated structure with one joint element or a plurality of joint elements that are arranged one behind the other or next to one another both in the circumferential direction and in the longitudinal direction. Particularly in the case of heart valve stents, a high degree of adaptability in the circumferential direction can be advantageous in order to adapt to anatomical structures such as calcifications.

[0021] The above object is further achieved by a catheter sleeve which is particularly suitable for inserting a stent-supported heart valve implant. The catheter sleeve according to the invention has a stiffening sleeve and a first polymer layer which is arranged radially within the stiffening sleeve. Furthermore, a second polymer layer is provided which is arranged radially outside the stiffening sleeve, wherein the above structure according to the invention forms a distal section of the stiffening sleeve, which is also referred to as the crown. In particular in the region of the crown, i.e. in the region of the structure according to the invention, the stiffening tube consists of a shape memory alloy, preferably of nitinol.A stiffening sleeve is understood to be a mechanically stable structure which, as part of the catheter sleeve, covers the implant, such as the stent-supported heart valve implant, during insertion of the catheter and, in the case of a self-expanding implant, holds it in its compressed form.

[0022] The catheter sleeve according to the invention, also referred to as an implant capsule, allows for expansion of the catheter sleeve to release the implant located therein due to its flexural flexibility at the distal end. Furthermore, the transmission of axial compressive forces during reheating is also possible, so that the catheter sleeve completely returns to its original shape after reheating. In particular, the structure can be expanded like a trumpet or funnel if the crown has a plurality of the above-described joint elements arranged side by side along its entire circumference. The bridge elements guide the joint element and determine its flexural flexibility. However, they are also capable of transmitting slight tensile forces to prevent the joint element from tearing apart.

[0023] In a preferred embodiment, the catheter sleeve according to the invention has at least two sections arranged one behind the other in the longitudinal direction, with a plurality of joint elements arranged circumferentially next to one another in each section, distributed over the entire circumference. The catheter sleeve according to the invention allows for easy release and retraction of an implant and subsequently returns smoothly to its original shape, thus avoiding deformation and thus undesirable interactions with the vessel when removing the catheter sleeve.

[0024] The above-mentioned task is achieved analogously by a catheter with the catheter sleeve described above. The catheter sleeve serves and is designed to accommodate a folded implant, in particular a stent-supported heart valve implant, and is connected to the outer shaft of the catheter. The implant is preferably fixed to the inner shaft of the catheter via a so-called prosthetic connector. As with conventional catheters, the outer shaft is guided and movable on the inner shaft.

[0025] Further objects, features, advantages, and possible applications of the invention will become apparent from the following description of exemplary embodiments of the invention with reference to the figures. All described and / or illustrated features, individually or in any combination, constitute the subject matter of the present invention, regardless of their summary in the individual claims or their interrelationships.

[0026] They show schematically Fig. 1 shows a catheter according to the invention before implantation of an implant in a perspective view from the side; Fig. 2 shows a distal section of the catheter from Fig. 1 in a perspective view from the side after the release of the implant; Fig. 3 a catheter sleeve according to the invention with outer shaft in a perspective view from the side; Fig. 4 a cross section through the catheter sleeve according to Fig. 3 at point C (see Fig. 3 ); Fig. 5 - 6 each show a distal section of the catheter sleeve according to Fig. 3 in a side view; Fig. 7 the distal section of a stiffening sleeve of a further embodiment of a catheter sleeve according to the invention in a side view; Fig. 8 a section of the inventive structure of the stiffening sleeve of the catheter sleeve according to Fig. 3 in a side view; Fig. 9 a section of the structure at the distal end of the stiffening sleeve of the Fig. 7 shown embodiment of a catheter sleeve according to the invention in a side view; Fig. 10 the joint element of the Fig. 8 und 9 Structures according to the invention shown in detail in a side view; Figs. 11 - 15 show further embodiments of joint elements of structures according to the invention in a side view; Figs. 16 - 17 show an implant, for example in the form of a stent or a stent section, in which a joint element is integrated into the tubular structure.

[0027] Fig. 1 shows a catheter 1 according to the invention with a handle 2a arranged at the proximal end of the catheter, a stabilizing section 2b, an outer shaft 3, and a catheter sleeve 4 arranged on the outer shaft 3, as used, for example, for the implantation of a self-expanding stent-based heart valve implant. A blunt catheter tip 5 is provided at the very distal end. The stabilizing section 2 shields the retractable outer shaft 3 from the introducer and the vessel wall, so that the outer shaft 3 can be freely retracted. The handle 2a serves to load, release, and retract an implant arranged in the catheter sleeve 4, for example, a stent-based heart valve implant. The catheter tip 5 forms the distal end of an inner shaft 7 arranged within the outer shaft 3 (see Fig. 2 ), wherein the catheter tip 5 is preferably made of PEBAX and is visible under X-ray irradiation.

[0028] Fig. 2 represents the distal end of the Fig. 1 sketched system after release of the implant. This figure also shows that a prosthesis connector 9 is arranged on the inner shaft 7, with which the implant is axially fixed to the inner shaft 7. The catheter sleeve 4 preferably has a ring 11 visible under X-ray irradiation at its distal end to facilitate observation. The catheter sleeve 4 is connected to the outer shaft 3 by means of a proximal connector 13. However, the catheter sleeve 4 and outer shaft 3 can also be made from one piece in other designs.

[0029] As already explained above, the implant is initially in the Fig. 1 In the state shown, the implant is arranged in the catheter sleeve 4 (also referred to as a capsule) in a compressed state and is held in this state by the catheter sleeve 4. The catheter sleeve 4 is connected to the handle 2a via the outer shaft 3. In this state, the implant, fixed and compressed in the catheter sleeve 4, is transported through the patient's vessels to the treatment site.

[0030] To release the implant, the catheter sleeve 4 is retracted proximally. The retraction is triggered via the handle 2a and transferred to the catheter sleeve 4 via the outer shaft 3. Initially, only a short distal section of the implant is released and its fit is checked. If the positioning is unfavorable, the catheter sleeve is pushed back distally using the handle 2a so that the implant is again covered by the catheter sleeve 4 and has completely entered the compressed state. The catheter 1 is then repositioned and the release of the implant arranged in the catheter sleeve 4 begins again. To avoid deformation of the catheter sleeve 4 during the release and, if necessary, retraction of the catheter sleeve 4, it must be particularly flexible and also be able to transmit axial and radial compressive forces well.

[0031] The catheter sleeve 4 is composed of a stiffening sleeve 40, which is embedded between an inner first polymer layer 41 and a second polymer layer 42 surrounding the stiffening sleeve 40 on the outside. The polymer layers 41, 42 enclose the stiffening sleeve 40 and, at their distal end, protrude beyond the distal end of the stiffening sleeve 40. The stiffening sleeve 40 is preferably made of a metallic material (alternatively: rigid polymer material) and has a proximal section 45 and a distal section 46, wherein the distal section is also referred to as the crown. The proximal section 45 is particularly preferably a partially slotted stainless steel sleeve. At the outermost proximal end of the proximal section 45, the stiffening sleeve 40 is connected to the outer shaft 3 via the proximal connector 13. The central axis of the stiffening sleeve 40 forms the longitudinal direction A (see Fig. 3 ) of the stiffening sleeve 40 or the catheter sleeve 4.

[0032] The distal portion 46 of the stiffening sleeve 40 is in the Fig. 5 and 6 and in an excerpt in Fig. 8 shown in more detail in an enlarged illustration. The distal section 46, made of Nitinol, has dovetail-shaped webs 51 at its proximal end, which engage with corresponding dovetail-shaped notches in the proximal section 45. In the distally adjoining section, the structure forms a ring 52, which is connected in the distal direction to webs 53 extending substantially in the longitudinal direction. These longitudinally extending webs 53 are connected to one another at their distal end via a wave-shaped web 55 extending in the circumferential direction U and encircling the entire circumference of the stiffening sleeve 40. The longitudinally extending webs 53 are wider distally and extend in the proximal direction in the shape of a two-pronged fork. In the region of its greater width, each longitudinally extending web 53 has a joint element 60, which is inserted into the Fig. 8 or 10 is shown again in detail. Fig. 8 shows an alternative embodiment in which the narrower fork webs 53, which run in the longitudinal direction A, each have a joint element 60.

[0033] The Fig. 10 The joint element 60 shown in detail has a main web 64 running in the longitudinal direction A (corresponding to the longitudinal direction of the tubular structure of the stiffening sleeve 40 or the catheter sleeve 4). In the structure according to the invention, the main web 64 forms a continuation of the respective longitudinally running web, which is designated by the reference numeral 53. In the center of the joint element 50, the main web 64 is completely severed, so that a gap 63 is created. In the circumferential direction U, next to the gap 63 or the main web 64, a bridging web 65 is arranged on each side, each of which forms an approximately semicircular shape and is connected to the main web 64 in the distal and proximal directions, respectively, in front of and behind the gap. The joint element 60 allows the transmission of axial compressive forces, i.e.of compressive forces that run in the longitudinal direction A, as well as radial compressive forces, so that the distal section 46 enables the structure to expand in the shape of a funnel. In the tensile direction, the joint element 60 has a lower rigidity, but the bridging web(s) 65 prevent the structure of the distal section 46 from drifting apart under slight tensile forces. Depending on the width B of the gap 63 of 40 µm - 500 µm, a spring function with a stop (maximum force) can also be realized. As a result, the catheter sleeve 4 according to the invention has particularly good flexurally elastic properties when an implant is released or withdrawn and returns completely elastically to its original shape, so that deformation can be avoided.

[0034] In the embodiment shown here, the main web 64 has a width D1 (measured in the circumferential direction U) of 50 µm - 500 µm and each bridge web 65 has a width D2 of 20% - 50% of the web width of the main web (measured perpendicular to the center line of the bridge web 65).

[0035] The Fig. 7 and 9refer to a second embodiment of a catheter sleeve 4a according to the invention with a slightly modified stiffening sleeve 40a. The distal section 46a has, analogously to the distal section 46 of the previous embodiment, dovetail-shaped webs 51 at the proximal end for connection to the proximal section 45a of the stiffening sleeve 40a. In the distal direction, a ring 52 adjoins this, which, through corresponding notches, gradually merges into webs 153 running in the longitudinal direction A. The longitudinally running webs 153 are connected to one another by means of a plurality of wave-shaped webs 155 running around in the circumferential direction U. At the distal end of the distal section 46a, between two sections with wave-shaped webs 155, joint elements 60 are provided, which are arranged on each longitudinally running web 153 and lie next to one another in the circumferential direction U. The joint element 60 is in Fig. 10 and has already been explained above.

[0036] In the Fig. 11 bis 15 Further examples of joint elements are shown. Fig. 11 The joint element 160 shown has, in contrast to the joint element 60 of the Fig. 10 V-shaped bridge elements 155. In the Fig. 11 In the illustrated embodiment of a joint element 250, the bridge web 255 is U-shaped.

[0037] The Fig. 13 bis 15 The given examples of joint elements 350, 450, 550 are similar to the Fig. 10 shown joint element 50, however, approximately at the level of the gap 355, 455, 555 in the area of ​​the respective bridge web 365, 465, 565, each have a section that has a notch to increase flexibility. This notch section (not shown) can only involve a reduction in the width or thickness of the respective bridge web 365, 465, 565 or, as shown in the figures, a change in the direction of the bend. This results in a U-shaped notch section 366 (or wave shape, see Fig. 13 ) or a V-shaped notch section 466 ( Fig. 14 ). This runs in Fig. 13 rather rounded and in Fig. 14 rather pointed. In Fig. 15 the notch portion 566 is W-shaped, which increases the spring property of the bridge web 565.

[0038] For implants such as stents, designs are also conceivable that have joints aligned in the circumferential direction U such that the main web (or node) is oriented in the circumferential direction U and is interrupted here by a joint gap. Such an embodiment is known as a stent or section of a stent in Fig. 16 The exact design of this example for the joint can Fig. 17 It can be seen that the cutout shape of the joint resembles a shortened bone or two hearts superimposed at their tips. The joints can also be used as a replacement for strut intersections to increase bending flexibility in the longitudinal and circumferential directions.

[0039] The above-described structure according to the invention, which can be used in a catheter sleeve or in an implant, enables the transmission of large radial and axial compressive forces while maintaining high bending flexibility. Bezugszeichenliste

[0040] 1 Catheter 2a Handle 2b Stabilizing section 3 Outer shaft 4, 4a Catheter sleeve 7 Inner shaft 9 Prosthesis connector 11 Radiopaque ring 13 Proximal connector 40, 40a Stiffening sleeve 41 First polymer layer 42 Second polymer layer 45, 45 Proximal section 46, 46 Distal section 51 Dovetail-shaped bar 52 Ring 53, 153 Longitudinal bar 55, 155 Wave-shaped bar 60, 160, 260, 360, 460, 560 Joint element 63, 163, 263, 363, 463, 563 Gap 64, 164, 264, 364, 464, 564 Main bar 65, 165, 265, 365, 465, 565 Bridge bar 366, 466, 566 Notch section (U-shaped, V-shaped or W-shaped) U Circumferential direction ALongitudinal direction of the stiffening sleeve 40 or the catheter sleeve or an implant BWidth of the gap D1 Width of the main bar 64 D2 Width of the bridge bar 65

Claims

1. Implant comprising a tubular perforated structure extending in the longitudinal direction (A) or in the circumferential direction and composed of a plurality of bars which extend at least partially in the longitudinal direction, wherein at least one joint element (60, 160, 260, 360, 460, 560), the main web of which (64, 164, 264, 364, 464, 564) extending substantially in the longitudinal direction has a continuous gap (63, 163, 263, 363, 463, 563), wherein the joint element (60, 160, 260, 360, 460, 560) has at least one bridge web (65, 165, 265, 365, 465, 565), preferably two bridge webs, wherein each bridge web (65, 165, 265, 365, 465, 565) is arranged in a circumferential direction (U) of the tubular structure next to the main web (64, 164, 264, 364, 464, 564) and is connected to the main web (64, 164, 264, 364, 464, 564) in the longitudinal direction (A) in front of and behind the gap (63, 163, 263, 363, 463, 563), characterized in that the width (D2) of the bridge web (65, 165, 265, 365, 465, 565) corresponds to at least 20% of the web width of the main web, and the sum of the width of all bridge webs of an articulated element does not exceed the width of the main web.

2. Implant according to claim 1, characterized in that the bridge bar (65, 165, 265, 365, 465, 565) is semicircular, U-shaped, V-shaped or meander-shaped.

3. Implant according to claim 1 or 2, characterized in that the bridge bar (65, 165, 265, 365, 465, 565) has at least one notch section (366, 466, 566).

4. Implant according to one of the preceding claims, characterized in that the gap (63, 163, 263, 363, 463, 563) has a width (B) of at least 20 µm, preferably of at least 40 µm - 500 µm.

5. Implant according to one of the preceding claims, characterized in that a plurality of joint elements (60, 160, 260, 360, 460, 560) are arranged next to one another in the circumferential direction (U).

6. Implant according to one of the preceding claims, characterized in that it consists of a shape memory alloy, preferably nitinol.

7. Implant according to any one of the preceding claims, wherein the implant is a stent, and further characterized in that the stent comprises at least in one portion a tubular perforated structure according to any one of the preceding claims.

8. Implant according to one of the preceding claims, characterized in that the at least one main bar extends in the longitudinal direction.

9. Implant according to one of the preceding claims, characterized in that several main bars run parallel to the longitudinal direction of the structure.

10. Implant according to one of the preceding claims, characterized in that the joint element is a structure which can transmit compressive forces, but also permits sliding in the region of the gap arranged in the main bar and rotation of the ends of the main bar opposite each other in the gap.

11. Implant according to one of the preceding claims, characterized in that the articulation element is further capable of transmitting compressive forces extending in the longitudinal direction or in the radial direction.

12. Implant according to one of claims 1 to 2 or 4 to 11, characterized in that the bridge bar has at least one indentation section with an indentation running transversely to the longitudinal direction.

13. Implant according to one of claims 3 or 12, characterized in that the notch section is designed as a U-, V- or W-shaped section.

14. Implant according to one of the preceding claims, characterized in that a large number of joint elements are arranged one behind the other in the longitudinal direction.