Delivery catheter, delivery system and covered stent

Abstract

The application discloses a delivery catheter for delivering and deploying a second covered stent, the second covered stent connected to a first covered stent, the catheter having: a delivery lumen having a distal orifice for delivering and deploying the second covered stent at a target site of a lateral branch of the first covered stent; and a guide mating member configured for receiving a guide element distally attached to a connection point at the side branch of the first stent graft, the connection point defining a stop unit. The invention further discloses a system comprising the delivery catheter and the covered stent and the covered stent.

Description

[0001] This application is a divisional application of the application with the application number 202110190229.6, the filing date of May 26, 2017, and the title of “Delivery catheter, system and covered stent”. TECHNICAL FIELD

[0002] The present disclosure relates generally to the field of medical devices. More specifically, the present disclosure relates to a vascular medical device, which is a covered stent, a stent graft or an endoprosthesis for fluid communication with one or more side branch vessels, and a system of such devices, e.g. a plurality of covered stents, for assembling with each other and for implantation at a target site of a patient. Further, a medical procedure for implanting such devices and systems is disclosed. The target site of the patient comprises at least a portion of the aorta of the patient, for example. More specifically, a treatment of at least a portion of the aorta of a patient by implanting such a device or system in a medical procedure is disclosed. The medical procedure is preferably a minimally invasive vascular repair. BACKGROUND

[0003] It is known to use modular covered stents or stent grafts for treating or repairing vascular diseases, such as aneurysms. WO 2005 / 027784 discloses a modular covered stent system for implantation in a diseased blood vessel, wherein the covered stent has an aperture along an intermediate portion of the covered stent. The aperture is used for aligning with a branch vessel of the main blood vessel, so that a further stent can be connected at the aperture from the main blood vessel stent. The aperture needs to be precisely aligned with the ostium of the side vessel. From the main blood vessel stent, another stent graft subsequently protrudes into the branch vessel.

[0004] In WO 2004 / 019823, an endovascular stent graft implantation system is disclosed for implanting a limb of a branched stent graft into a blind vessel. The branched stent graft has a main body and a limb extending from the main body. The branched stent graft is mounted on a dilation device having a separate deflection guide wire extending into the limb. The method of implanting the branched stent graft into a blind vessel in a human or animal body includes releasing the limb from the branched device, extending the guide wire from the limb into the blind vessel, manipulating the implantation device by slightly withdrawing the device so that the limb enters the blind vessel with the aid of the guide wire and releasing the stent graft from the dilation device.

[0005] An undesired problem of such known devices is that it is difficult for the operator to correctly implant the covered stent in the main blood vessel in alignment with the branch vessel. The aperture from the main blood vessel covered stent or the branch has to be correctly positioned in the main blood vessel relative to the position of the branch vessel. The branch vessel is in fluid communication with the main blood vessel, i.e. connected with the branch vessel covered stent or a part of the larger stent graft unit with an arm.

[0006] The main vessel covered stent is expanded and thereby implanted into the main vessel. Once expanded and implanted, the main vessel covered stent cannot be repositioned. Misaligned orifices or branch covered stents that are misaligned with the branch vessels can for example cause kinking of the branch vessel covered stent. This kinking can lead to an undesired reduction of blood flow to the branch vessels. Due to the pulsatile flow, the durability and lifetime of the covered stent can also be damaged upon implantation. It can also lead to a leakage or loosening of the side branch covered stent unit from the main vessel modular covered stent.

[0007] Furthermore, when the operator tries to find the branch vessels with the modular covered stent, especially in the presence of some kind of misalignment, there is a certain risk of damaging the vessel. The prior art modular covered stents with orifices have a further risk of causing damage to the vessel wall during the operation, because they are more or less open circular orifices facing the side of the modular stent. When the operator subsequently tries to navigate such side branch vessels into place, as described above, the open orifices can tear or otherwise damage the delicate vessel wall when moving inside the vessel, so that the vessel wall can rupture causing internal bleeding. This should be avoided and an improved covered stent or (modular) covered stent system or the implantation procedure of the latter would be advantageous.

[0008] The challenging alignment described above makes the operation time of the hitherto known devices and medical procedures very long. A long operation time increases the patient risk and potential problems associated with such procedures. These problems include for example an increased risk of clots occurring during the procedure. Also, a long operation time means a long time of X-ray usage, both for the operator and the patient being exposed to X-rays. Furthermore, a lot of contrast agent is used.

[0009] It is therefore also desirable to reduce the X-ray dose for the patient and the operator. A shorter scan time or fewer scan positions and a reduction of the use of contrast agent that needs to be injected into the patient's blood are desirable. It is therefore desirable to reduce the time needed for such implantation procedures, both reducing the primary radiation exposure of the patient and the secondary radiation (scattered radiation) of the operator. It would be advantageous to provide a covered stent, a covered stent system or a procedure that reduces the scan time. The embodiments of the invention described below will provide such advantages as described below.

[0010] A further undesired problem of the known technology is the implantation of the covered stent implant, especially the longer endoprosthesis system of such covered stent covering multiple side branch vessels is a complex operation.

[0011] In known endoprosthesis, the covered stent needs to be assembled in a single placement of the covered stent system. For example, when the side branch vessel openings of the main covered stent are positioned incorrectly when deployed with respect to the side vessels, repositioning of the main (vessel) stent is very difficult or impossible. For incorrect positioning of the main stent with respect to the side vessels, the prior art systems do not allow for flexibility or very small tolerances in placement. There is a need to achieve flexibility with respect to the side vessels with such stents.

[0012] It would be advantageous to provide for repositioning of other parts of the stent implant system with respect to the side vessels and to facilitate the placement procedure. Therefore, there is a need for a novel covered stent, covered stent system or implant procedure to allow for single positioning of one or more side vessel stent implants. The embodiments of the invention described below provide for this advantage as described in more detail below.

[0013] Minimally invasive implantation of endoprostheses requires so far continuous fluoroscopy scans by X-ray so that the operator can see where and how the different covered stent modules are positioned in the patient's vascular system to assemble the endoprosthesis in the patient's body.

[0014] The scan angle of the X-ray modality needs to be changed frequently to enable the operator to find the three-dimensional branching vessels and the relationship of the covered stent to the orifice of the covered stent module in the main vessel. The scan technique used for this only enables the operator to see the scanned object in one plane at a time, i.e. in two dimensions, one layer at a time.

[0015] Three-dimensional visualization of the branching vessel positions and orifices with respect to the orifices of the covered stent requires repeated movement of the fluoroscopy scanner arm from one plane to another and back to the first plane again. This needs to ensure three-dimensional alignment between the covered stent in the main vessel and the side branching vessels. It is important to place the assembly in the correct position at the patient's implant site.

[0016] This task becomes particularly complex due to the multiple orifices and side branching vessels connecting to a single covered stent in the main vessel.

[0017] There is a need to make the assembly less complex. The disclosure of the following embodiments of the invention advantageously provides for a less complex covered stent assembly. Reduced X-ray time and associated radiation dose are advantageous for the patient and the clinical staff.

[0018] Therefore, there is a need for a safer medical device and / or system or medical procedure to avoid the above-mentioned drawbacks of known systems and procedures. Preferably, a device and / or system or method is desired which makes the operating time shorter. It is desirable that the procedure is easier to perform by the operator. A simplified implantation procedure is needed. It is desirable to have a new medical procedure with reduced patient risk. A simpler implantation is needed. It is needed to perform medical procedures which would in fact be avoided in the current patient risk assessment. For example, known stent systems imply an excessive risk of complications and a thoracotomy is not an option for many patients, in particular elderly patients, a need for such a simplified implantation or a device facilitating a simplified implantation. It is also desirable to need less X-ray dose during the procedure. Therefore, it is desirable to be able to provide a novel medical procedure which means a reduction of patient risk. SUMMARY

[0019] Therefore, embodiments of the present disclosure preferably seek to alleviate, mitigate or eliminate one or more of the drawbacks, disadvantages or problems in the art, e.g. by providing a medical device, system and method according to the appended independent claims, alone or in any combination.

[0020] The novel covered stent system of the present invention allows in particular the individual delivery of side vessel stent branches. This greatly reduces the total operating time. Moreover, when the operator deploys a side vessel stent, the patient safety is improved with reduced time and / or other side vessels still being perfused.

[0021] The novel system requires a novel medical procedure which means an excessive risk for the patient. Since the implantation is simpler, medical procedures can be performed which are avoided in the current patient risk assessment, e.g. known stent systems imply an excessive risk of complications and a thoracotomy is not an option for many patients, in particular elderly patients.

[0022] The embodiments of the present invention described below facilitate a reduction of the time of part or the whole procedure. The implantation time is shortened compared to prior art systems, thus, e.g. facilitating a reduction of the total dose. The angle of the X-ray modality is changed less than in prior art systems. Less contrast agent is needed. All the below disclosure serves to reduce potential side effects for the patient. Moreover, the cost of the procedure will be reduced.

[0023] The covered stent discussed herein is in one embodiment self-expanding or in another embodiment expandable by another device, e.g. an inflatable balloon.

[0024] According to a first embodiment, a medical device is provided. The device is a covered stent having a main body and at least one lateral side branch connected to the main body. The side branch is flexible and expandable.

[0025] According to one aspect of the present disclosure, a system is provided.

[0026] The device and / or system can be used in the medical procedures and methods described herein.

[0027] Aspects of the present disclosure include, but are not limited to, the following.

[0028] - In a first aspect, a covered stent is provided having a main body and at least one branch comprising one, two or three branches connected to the main body. The covered stent further comprises at least one bendable and / or flexible guide element permanently or releasably connected to the inside of said at least one of the branches at a connection point, preferably at a distal orifice of said branch. The guide element is proximally arranged inside the main body, passing and along a proximal portion of the main body and extending proximally along a proximal opening of the main body. In this way, a catheter can be guided over the guide element through the main body towards the distal orifice of the branch.

[0029] - In a second aspect, a delivery catheter is provided for delivering a second covered stent for connection to a first covered stent. The catheter has a delivery lumen with a distal orifice for delivering and deploying the second covered stent at a target site of the catheter of the first covered stent. The catheter further has a guide fitting for receiving a guide element distally attached to a connection point at a branch. In this way, the catheter can be slid over the guide fitting along the guide element to the orifice of the branch and the second covered stent is delivered and deployed through the delivery lumen of the catheter. The guide fitting for receiving the guide element preferably has a distal end positioned at a distance from the distal orifice of the delivery lumen such that the delivery lumen extends beyond the connection point when the guide fitting distal end engages the connection point.

[0030] - A modular system of the covered stent according to the first aspect and the delivery catheter according to the second aspect, wherein the guide element passes through the guide fitting for delivering a second stent implant through the delivery catheter to the target site of said branch. The second stent implant is preferably an extended stent implant.

[0031] - A modular covered stent system comprising a plurality of covered stents, wherein at least one covered stent is preferably a covered stent of the first aspect of the disclosure. The plurality of covered stents are configured to be interconnectable to each other. The plurality of covered stents comprises a first main vessel covered stent having a first single distal upstream inlet branching into at least two proximal downstream outlet branches, and at least two covered stents having at least one lateral side branch aperture. Each of the at least two covered stents are distally interconnectable to one of the downstream outlet branches of the first main vessel covered stent, and laterally connectable to a side flow vessel of the main vessel. The at least two covered stents can be sequentially interconnected to one of the downstream outlet branches for providing a blood conduit arranged in parallel by the at least two covered stents. The modular system comprises a second main vessel covered stent having at least two distal upstream inlet branches converging in a single proximal downstream outlet, each distal inlet branch being interconnected to a proximal outlet of one of the at least two covered stents.

[0032] - A method for navigating a covered stent to a vascular target site, comprising providing a covered stent of the first aspect of the disclosure. Further, the method comprises delivering the covered stent to the vascular target site, and navigating the branch of the covered stent into or towards a branch vessel. The method comprises providing a catheter according to the second aspect of the disclosure, and arranging a guide element attached to the covered stent by a guide fitting of the catheter, advancing the catheter along the guide fitting until its attachment point stops further advancement. The method comprises delivering a second stent implant or a guidewire thereof through a lumen of the delivery catheter to a target site of the branch of the covered stent, the second covered stent being preferably an extension stent implant. The method can optionally comprise proximally fixing the extension stent implant to the branch and distally fixing in the branch vessel.

[0033] - A medical procedure comprising accessing a target site as a patient's vessel, and delivering a first covered stent through a delivery catheter inside the vessel at the target site. The target site has a side branch vessel, and the method comprises delivering a second covered stent to the first covered stent and connecting the first covered stent to the second covered stent to provide blood flow to the side branch vessel. The delivery of the second covered stent comprises sliding a catheter along a guide element to a position inside a lumen of the side branch of the first covered stent. The method can comprise expanding the second covered stent to connect to the first covered stent.

[0034] - A medical procedure comprising accessing a target site as a patient's vessel, and delivering a first covered stent through a delivery catheter inside the vessel at the target site. The target site has a side branch vessel, and the method comprises expanding the side branch and delivering a second covered stent to the first covered stent and through the side branch to the side vessel. The method comprises connecting the first covered stent to the second covered stent to provide blood flow to the side branch vessel.

[0035] A medical procedure for aortic vascular reconstruction includes delivering covered stent modules in a specific order. The method can start with implanting a three-leg covered stent in the ascending aortic arch. The method includes delivering two parallel covered stents in the aortic arch in a downstream direction of the aorta, each covered stent having one side branch, and sequentially connecting the parallel covered stents to the legs of the three-leg covered stent and to branch vessels of the aortic arch. The method includes delivering a covered stent that collects the parallel covered stents downstream of the aorta. For example, the collection includes providing two distal legs that are incorporated into a single lumen having a proximal orifice, connecting the two distal legs to the proximal end of one of the two parallel stents, respectively. Thus, different numbers of parallel covered stents beyond two change the number of legs. The intermediate collection number of legs can be provided by the devices, systems, and methods.

[0036] Other embodiments of the present disclosure are defined in the dependent claims, wherein the features of the second and subsequent solutions of the present disclosure are the same as the first solution, mutatis mutandis.

[0037] Some embodiments of the present disclosure provide improved navigation and assembly of a covered stent or multiple covered stents, each in a side branch vessel from a main vessel.

[0038] Using the innovative system, device, and / or method, the procedure of positioning covered stents with side branch connections, particularly for multiple side vessels with, for example, three or four side branches (up to four side branches), is expected to significantly reduce the time required for implantation, by several hours less than conventionally required. Using traditional pre-fabricated stent implants, such a procedure takes a considerable amount of time, on the order of 10 hours of operating time or more. Despite the significant reduction in the procedure time for positioning the covered stent device / system, there is no loss of surgical safety. On the contrary, safety can be improved. The delivery of the device and system of the present innovation is very reliable. The possible implantation procedure by the novel modular system and / or its components and / or system features significantly reduces the implantation time. This will be described in detail below.

[0039] A covered stent refers to a stent having a lining, a casing, or surrounded by a fabric or material that is impermeable to liquids. The covered stent can be partially or completely covered. A covered stent can also be referred to as a stent graft or an endoprosthesis.

[0040] The side branch 3 can be laterally extendable and / or collapsible, i.e., expandable in a longitudinal axis direction of the side branch 3, which is preferably substantially perpendicular to the longitudinal axis of the main body 2 of the covered stent 1. Alternatively or additionally, the side branch 3 can be expandable in a lateral direction, i.e., can be expandable perpendicular to the axis direction of the side branch 3. The side branch 3 can comprise a covered stent, and in some embodiments can be a covered stent.

[0041] In embodiments, the side branch 3 can extend laterally about 1 cm to 1.5 cm.

[0042] The side branch 3 is in embodiments integral with the main body 2, or the covering of the main body 2 and the covering of the side branch 3 are integral, or the cap of the main body 2 and the cap of the side branch 3 are integral. In one embodiment, the cap and the covering of the main body 2 are integral with the cap and the covering of the side branch 3. When the side branch 3 comprises a covering, it is stiffer and can resist more handling, such as placement and / or re-placement of any further covering of the extended covering of the side branch 3. This also allows the side branch 3 to form a tighter connection with any additional covered extended covering of the side branch 3.

[0043] It should be emphasized that, when used in this specification, the terms "comprises / comprising" and "includes / including" are used on the basis and open ended terminology that, as used in suitably context, specify the presence of stated features, integers, steps or components but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. BRIEF DESCRIPTION OF DRAWINGS

[0044] These and other aspects, features and advantages of embodiments of the present disclosure will be apparent from the description of embodiments of the present disclosure, reference being made to the drawings, in which

[0045] Figure 1 is a schematic representation of a system for implanting different covered stent modules within the aortic arch and thoracic aorta of a patient;

[0046] Figure 2 is a schematic representation of a system for implanting Figure 1 is a schematic representation of a system for implanting

[0047] Figure 3 is a schematic representation of a covered stent with three legs, and navigation elements and sutures for easy navigation to all three legs;

[0048] Figure 4 is a schematic representation of a covered stent with a side branch;

[0049] Figure 5a -b is a schematic representation of two embodiments of a covered stent with more than one side branch;

[0050] Figure 6 is a schematic representation of one embodiment of a side branch from below to above, which can self-expand from a collapsed shape to an expanded shape;

[0051] Figure 7 is a schematic representation of a covered stent with a folded or folded side branch, which is used to position a branch vessel;

[0052] Figure 8This is a schematic diagram of a covered stent with side branches and a catheter with a guiding fitting for guiding the catheter to facilitate navigation of the side branches;

[0053] Figure 9a -c is a schematic diagram of the restraint member and the overcoating support, which expands from a contracted shape to an expanded shape by removing the restraint member;

[0054] Figure 10 This is a schematic diagram of a sheath used to hold a covered stent in a contracted or closed manner, and to controllably release the covered stent partially or completely.

[0055] Figure 11 This is a schematic diagram of the covered stent before and after it is fully deployed;

[0056] Figure 12 This is a flowchart of one embodiment of a medical procedure;

[0057] Figure 13 This is a flowchart of an embodiment of a method for navigating a covered stent to a branch vessel;

[0058] Figure 14A -D is a perspective view, top view, side view, and front view of an embodiment of a modular covered stent 300 with a single lateral branch;

[0059] Figure 15A These are perspective and sectional views (upper part of the figure) of the modular film-coated support 300, and perspective views (lower part of the figure) of the lateral side branches of the transport structure.

[0060] Figure 15B and 15C It unfolds before the main body is released. Figure 15A A schematic diagram of the lateral side branches of the modular film-coated stent 300;

[0061] Figure 16 This is a cross-sectional view of a double-lumen delivery catheter;

[0062] Figure 17A These are perspective and sectional views of a modular film-coated support 300, which has lateral side branches in another delivery configuration;

[0063] Figure 17B This is a schematic diagram showing the release of the main body and lateral side branches of the modular covered stent 300;

[0064] Figure 18 This is a schematic diagram of a conduit tool for releasing the navigation unit from an extension of a lateral branch; and

[0065] Figure 19A B and 20 are schematic diagrams of different support patterns for the lateral side branches. DETAILED DESCRIPTION

[0066] Specific embodiments of the present disclosure will now be described with reference to the drawings. However, the present disclosure can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the present disclosure to those skilled in the art. The terminology used in the detailed description of the embodiments illustrated in the drawings is not intended to limit the present disclosure. In the drawings, like numbers refer to like elements.

[0067] The following description focuses on embodiments of the present disclosure that can be applied to medical devices, and in particular to medical devices that facilitate navigation and assembly of a covered stent or multiple covered stents in communication with a side branch vessel. The implants can be used to treat and / or repair vascular disease, such as an aneurysm. This embodiment is illustrated by way of deployment in the aorta. Blood vessels like the aorta can be structurally compromised for different reasons and require repair along at least a portion of the aorta 500. Sometimes extensive endoprostheses are required for aortic repair, descending partially or entirely from the ascending aorta 501 through the aortic arch 502 to the descending aorta 503 and along the abdominal aorta 504 past the renal arteries 505.

[0068] Embodiments of such endoprostheses, including modular embodiments and assemblies, are described in Figure 1 and 2 and corresponding text herein. Full aortic reconstruction or repair can be provided when the entire system is implanted, as shown in Figure 2 Selected sub-modules of the system can be implanted alone to provide partial aortic reconstruction or repair. However, other anatomies can be provided for treatment using devices and / or systems of the present disclosure, including abdominal covered stents, peripheral stent grafts, endoluminal prostheses, and including, for example, laparoscopic stents. But not limited to peripheral veins, leg arteries, spinal cord, neural structures, lymphatic system, etc.

[0069] Figure 1 and Figure 2 Systems of various covered stent modules 200, 300, 310, 320, 400, 410, 420, 430, 600 for implantation within the aortic arch 502 and abdominal aorta 504 of a patient are shown. Figure 2 Systems 100 of Figure 1 are shown implanted within the aorta 500 of a patient and the modules are connected to one another. Figure 1 An additional extension stent graft implant 600, not shown in Figure 2The prosthesis provides reliable blood communication in the main vessel, here the aorta 500, and into the branch vessels, here the carotid vessels, the renal arteries 505, etc. In the illustrated embodiment, the aortic wall has a weakening / aneurysm in the descending aortic arch and abdominal aorta, requiring treatment for aortic replacement / repair provided by the exemplary stent graft system 100.

[0070] In the illustrated embodiment, a plurality of stent grafts 1 (the reference numeral "1" as used throughout this specification can be considered a placeholder for "stent graft" or "plurality of stent grafts", e.g. of the type disclosed herein, e.g. stent grafts 200, 300, 310, 320, 400, 410, 420, 430, 600, etc.) are assembled and interconnected to fit the entire portion of the patient's aorta or the entire aorta to form the system 100 or its modular subsystems. The stent grafts 1 discussed herein can also be implanted at other target sites in the body for repairing and / or reestablishing a vascular conduit for liquid communication through the blood vessel.

[0071] Figure 1 Different kinds of modular stent grafts 1 are shown, which can be used in the exemplary assembly of the system 100 of modular stent grafts 1, which fit within and around the aortic arch 502 of the patient. The system 100 can be assembled in vivo or ex vivo.

[0072] Alternatively, the system can include more or fewer stent graft modules. For example, only the aortic arch can be covered by stent graft modules 200, 300, 310, 320, 400, 410, etc. - all depending on the treatment site and treatment needs. Other embodiments of combinations of stent graft modules are: a) 200, 2x300+2x600, 400 and optionally 600 in 201; b) 420, 310+ optionally 2x600, 320+ optionally 2x600 and 430; c) intermediate 410+ embodiments a) and b); etc.

[0073] Some stent grafts 1 have side branches 3, which are provided for extending blood communication through the system, and preferably into branch vessels. Embodiments of such stent grafts are the modular stent grafts 300, 310, 320.

[0074] Some stent grafts 1 have legs, i.e. the body 2 of the stent graft 1 is divided into two or more tubular portions. Embodiments of such stent grafts are the modular stent grafts 200, 400, 420, 430.

[0075] Alternatively or additionally, although not shown in the figures, the covered stent 1 can have two side branches 3 and legs. The covered stent 200 can be considered an embodiment with two legs 202, 203 and a side branch 201. In this text, both legs and side branches can be considered branches. Other covered stents not discussed or shown herein but currently in common use can also be used in the system 100.

[0076] The modular covered stent system 100 comprises a plurality of covered stents 1, of which at least one is a covered stent 1. The plurality of covered stents 1 is configured to be connectable to each other.

[0077] Alternatively or additionally, the system further comprises an elongated navigation element 20 which allows the operator to navigate the covered stent and / or side branches 3 of the covered stent 1 and to align the side branches 3 with the branch vessel. The elongated navigation element 20 is preferably a guidewire, such as shown in Figure 1

[0078] In an embodiment, the covered stents have substantially the same diameter at the mutual connection between two covered stents to provide a liquid tight interconnection.

[0079] In an embodiment, having the same diameter at the mutual connection means that the outer diameter of the mutual connection of one covered stent is substantially the same as the inner diameter of the mutual connection of the other covered stent, at least along a portion of the covered stents. If overlapping, the same diameter is maintained at least along the overlapping portion of the two covered stents. Thus, the liquid transport of two covered stents is connectable, for example by overlapping each other, and one tube within the other.

[0080] The stent structure of a covered stent is a part of the covered stent. It can have a pattern, such as a wave shape. The pattern can be made by braiding, weaving, laser cutting a tube, etc. The structure is a stent, for outwardly supporting the structure and providing a substantially tubular structure to ensure unimpeded flow of blood through the tube when implanted. Covered with a suitable liquid tight cover.

[0081] The wave shape or pattern can be denser at the overlapping connection area than other areas of the covered stent - for reliable liquid tight connection of two covered stents and by improved mechanical strength.

[0082] Figure 19A Figures of some exemplary stent patterns / wave shapes of lateral side branches, B and 20.

[0083] Figure 19A The pattern in Fig. 2 shows a wave shape (nitinol) wire or laser cut structure which is easily reduced in its outer diameter and collapsed next to the prosthesis body into a delivery configuration. Upon release from the catheter or removal of the constraining member, it will longitudinally elastically expand, as shown in Figure 19B ​and Figure 20 as in the design of

[0084] Figure 19A The pattern in A, B has an area in area 3b without a support frame that the extension prosthesis 600 will overlap with. The frame pattern has an asymmetric design. The dotted line 3c in the figure represents the area that will cause the stent to collapse. This design requires less collapsing force and less space to store it for delivery in an outer sheath. The part with the longer support frame (on the left side of the figure) will ensure that the side branch prosthesis expands with sufficient length that will stay in the side branch or be oriented radially outwards from the main body.

[0085] Figure 20 The pattern in A, B has an area in area 3b without a support frame that the extension prosthesis 600 will overlap with. The frame pattern has an asymmetric design. The dotted line 3c in the figure represents the area that will cause the stent to collapse. This design requires less collapsing force and less space to store it for delivery in an outer sheath. The part with the longer support frame (on the left side of the figure) will ensure that the side branch prosthesis expands with sufficient length that will stay in the side branch or be oriented radially outwards from the main body.

[0086] The collapsing of the side branch 3 for delivery through a catheter can be obtained in various ways. It can collapse backwards, slide sideways along the catheter lumen, or be compressed along its longitudinal axis. If a cap is provided (Fig. 9 and the like), the side branch and the covered stent are collapsed and held within the cap / constraining member 8. The constraining member 8 can be of a material with low friction, such as PTFE. The constraining member 8 allows the pull / push release of the covered stent contained in the constraining member 8 during delivery until deployment. Alternatively or additionally, the interior of the catheter can be provided with a material with good sliding properties to facilitate the movement of the covered stent along the lumen to the target site, wherein the constraining member optionally covers the covered stent during delivery until final implantation.

[0087] In another embodiment with the same diameter, meaning that the two covered stents to be connected have substantially the same inner diameter at the mutual connection and are connected in a non-overlapping manner, for example, end-to-end connection. A further inner liner can be provided at the connection site of the two covered stents, preferably downstream from the interior of the upstream positioned covered stent into the downstream oriented covered stent.

[0088] In one embodiment, the two covered stents to be interconnected have substantially the same inner diameter and substantially the same outer diameter at the interconnection and the covered stents are connected by overlapping them when one of the covered stents is in a partially collapsed or collapsed state.

[0089] Covering stents with the same or substantially the same diameter makes it easy for the operator to connect various covered stents, as the diameters of the respective covered stent components of the system 100 are similar and the operator does not need to worry about any specific connection method, stent shape, connection site, etc. This means that the operator only needs to consider whether the previous covered stent was a single stent, a double stent, a triple stent, or a leg stent. This also makes the manufacturing of covered stents easier, as the diameters at the connections of various covered stents are the same. One embodiment is the diameter of the legs 202, 203, the covered stent body 300, and the upstream oriented leg of the covered stent 400.

[0090] The overlapping areas allow for length adaptation of the modular system. For example, the modular covered stents 400, 410, 420 can be provided as a single unitary unit. However, a straight intermediate covered stent 410 is provided separately from the end piece covered stents 400, 420 of the branch to allow for adjustment to the specific patient anatomy (in this embodiment, the length of the abdominal aorta is different). The overlap of the intermediate covered stent can be changed accordingly. The length adjustment of the modular covered stent system is provided by the overlapping sections at the openings of the covered stents, allowing for changing the overlap and determining the overall length of the assembled modular system at implantation. This applies to the side vessel expanding covered stent 600 connection, etc.

[0091] In the prior art, systems of covered stent modules are provided with covered stents having different diameters, such as conical shapes. They achieve a connection by inserting a first converging conical covered stent into a second expanding conical covered stent. When the first covered stent expands, the two covered stents form a connection. In addition to keeping track of all covered stent modules, such a system creates an unnecessary additional task of not only keeping track of the correct order and correct orientation before and during the entire operation, but also of where and how the two cones fit into each other. In contrast, embodiments of the present disclosure provide a much simpler, safer, and faster implantation process.

[0092] Providing covered stents 1 with substantially the same diameter gives the advantage that the operator can implant each covered stent 1 as described above, or in any orientation that he or she deems best. This will greatly shorten the time required to assemble the system 100 and thus the operation time.

[0093] In one embodiment, when the covered stent 1 has substantially the same diameter as described above and is expanded, or when the side branch 3 or leg of the covered stent 1 is expanded, the flow through the covered stent 1 is more or less not disturbed by it. Meaning that liquid, e.g. blood, entering one side, e.g. the body 2, will pass through the covered stent 1 and out through, e.g. the two legs of the other side and due to the expansion and same diameter of the connections at the covered stent 1, the inlet and outlet area is substantially the same. This allows the operator to concentrate on connecting one covered stent 1 or part of a covered stent 1, e.g. a leg. The operator does not have to worry that the covered stent 1 will disturb the flow or flux through the covered stent 1 or in the blood vessel.

[0094] In addition, this allows the use of a covered stent or multiple covered stents in the system and assembly at the implantation target site, i.e. not pre-manufactured for a specific patient. This is an advantage over known systems. Known systems comprise a patient-specific endoprosthesis which is pre-built up to now. Typically, an image modality is used to scan the vascular system including the target site, e.g. a weakened aorta, at an earlier time. Then the endoprosthesis is manufactured based on the imaging data and delivered to the surgeon for implantation. This manufacturing of a patient-specific endoprosthesis typically takes several days to weeks, which is undesirable. During this waiting time, the anatomy of the blood vessel can change. As a result, the manufactured endoprosthesis can no longer fit the patient. Also, the waiting time is undesirable because the patient is in most cases in urgent need of the endoprosthesis, e.g. to avoid a rupture of an aortic aneurysm. However, if desired, the specific embodiments of the covered stent of the present disclosure can also be customized to the patient. However, standard devices of different sizes which can easily be used for implantation are preferred because this avoids the waiting time due to manufacturing.

[0095] The modular covered stent system 100 can further comprise a guiding element 10, like a suture or a wire. Along the guiding element 10, a delivery catheter can be threadably connected to a distal end of the guiding element 10 in a proximal direction. The guiding element 10 is fixed distally to the covered stent, e.g. the suture can be fixed by a knot, a pin, a weld, an adhesive or the like. Thus, the guiding element 10 is fixed to the covered stent. Preferably, the attachment point of the guiding element 10 to the covered stent is located internally, e.g. at the position of a lateral side branch of the covered stent. The guiding element 10 is preferably preloaded in the delivery catheter of the covered stent. The guiding element 10 serves as a manipulator for the guiding fitting 9 of the catheter in use. The guiding element 10 is preferably bendable and / or flexible.

[0096] In embodiments, the guiding element 10 is thus permanently or releasably attached distally at the connection point, preferably at the distal orifice of the branch 3, to the interior of the branch, e.g. the lateral side branch. The guiding element 10 is arranged proximally inside, through and along another portion of the main body 2 or another branch 3, and extends proximally through the proximal opening of the main body 2 (see e.g. Figure 3 or 8). Thus, in use, the guiding element is used to guide the catheter over the guiding element 10 through the main body 3 towards the distal orifice of the lateral side branch 3.

[0097] See Figure 3 or 8 and the corresponding text below for more detailed descriptions of embodiments of the guiding element 10 and its corresponding use and application in the modular stent graft system.

[0098] Alternatively or additionally, the guiding element 10 can be attached distally to the patient's aorta at the desired target location.

[0099] Alternatively or additionally, the attachment of the guiding element at its distal end can be releasable, preferably releasable from outside the main body, to remove the guiding element as needed during the implantation procedure. A knot can be releasable, a thermal disconnection device can be provided for controlled disconnection of the guiding element at the attachment point. Alternatively or additionally, the guiding element can be configured to be cut off after use. Suitable tools can be used for cutting, e.g. a sheath with an internal secure cutter that slides over the guiding element towards the attachment point and along the guiding element towards the attachment point, wherein the cutter is activated and the guiding element is cut off. The guiding element can then be reliably retracted outside the body, e.g. inside the sheath with the cutter, or simply pulled proximally out of the vasculature through the puncture site / introducer.

[0100] However, the guiding element 10 is preferably left in place at the end of the implantation procedure. The guiding element 10 can be left in place after use (guiding e.g. the extension stent graft's delivery and deployment). It can be made of biodegradable material or bioabsorbable material. In any case, the guiding element 10 is made of biocompatible material, including absorbable agents such as polyglycolic acid, polylactic acid, monocrystalline and polydioxanone, and non-absorbable nylon, polyester, PVDF and polypropylene, PTFE or dacron. The guiding element 10 can be made of a metallic material, e.g. nitinol or stainless steel, or a suitable metal alloy, which can facilitate durability during implantation. This is advantageous when the guiding element is left in place after the end of the implantation procedure of the modular covered stent system. Since the guiding element does not need to be detached or cut off at or near the connection point, the procedure can be shortened. It can be cut only proximally, or not at all.

[0101] Along the guiding element 10, the delivery catheter 30 can be moved towards the distal end of the guiding element 10, for example by a guiding fit 9 on the catheter, as described below Figure 8 ). Another element, device or unit can then be delivered through this delivery catheter to a desired position at the distal end of the guiding element 10. It can be beneficial to reduce or omit X-ray guidance, probing, navigation attempts, etc.

[0102] In this way, the catheter can be moved along the guiding element to or towards its distal end without the need for fluoroscopic guidance. In this way, reliability and delivery speed are improved, while radiation exposure can be reduced.

[0103] Such a delivery catheter 30 is provided for delivering an extension stent implant 600. The catheter 30 has a delivery lumen with a distal end orifice for delivering and deploying the extension stent implant 600 at a target site at a lateral side branch 3 of a covered stent 1.

[0104] The catheter 30 further has a guiding fit 9 for receiving a guiding element 10 attached distally to a connection point at the branch 3. Thus, the catheter 30 is configured to slide along the guiding element 10 over the guiding fit 9 to the orifice of the branch for deploying the element, e.g. the extension stent implant 600, through the delivery lumen of the catheter.

[0105] The guiding fit 9 for receiving the guiding element has a distal end that is positioned at a distance from the distal end orifice of the delivery lumen. In this way, the delivery lumen extends beyond the connection point when the distal end of the guiding fit 9 engages the connection point.

[0106] For example, as Figure 8 shown, the distal end of the delivery catheter 30 can be pre-curved to advantageously enter the side vessel from the branch orifice. This way, the operating time is reduced, the fluoroscopy load of the patient and clinical staff is reduced, and the implantation can be more safely and reliably.

[0107] A modular stent implant system is provided, comprising a covered stent 1 and a delivery catheter 30 having a guiding element 10 that is settable or arrangeable through a guiding fit 9. In this way, a unit such as an extension stent implant 600 is advantageously deliverable through the delivery catheter 30 to a target site at the branch 3.

[0108] Further, the distal end of the guiding element 10 is arranged, for example, at a marker 21. Alternatively or additionally, the guiding element 10 can be provided with a marker itself. The marker refers to a fiducial marker visualizable by a suitable imaging device for the surgeon performing the implantation procedure. The marker 21 is preferably arranged at a leg 4 of the covered stent for guiding the other covered stent towards and / or through a distal orifice of such leg 4 (e.g. as described below) towards a side branch vessel of the main vessel. The marker can be elongated and extend along at least a portion of the length of the guiding element 10, for example as a radiopaque multifilament thread / suture / thread and / or one or more marker bands.

[0109] For easier positioning of the other covered stent relative to the leg of the first covered stent, the marker 21 is provided, for example, on the leg of the first covered stent. In the same way, the marker 21 can be provided on the side branch 3 of the covered stent 1, which makes the covered stent 1 easier to align relative to the branch vessel. Position confirmation can then be performed using X-ray, which means a reduced dose compared to full X-ray supported navigation using contrast agent.

[0110] The illustrated modular covered stent system 100 comprises a first main vessel covered stent 200, 420 having a first upstream inlet branching into at least two downstream outlet branches.

[0111] Further, it comprises a covered stent type 300, 310, 320 having a main body and at least one lateral side branch connected to the main body. The lateral side branch is preferably flexible and expandable. The covered stent is interconnectable with one of the downstream outlet branches and is connectable laterally to a side flow vessel of the main vessel through its lateral side branch. Thus, at least two covered stents 300, 310, 320 are sequentially interconnectable to one of the downstream outlets of the main vessel covered stent 200. In this way, a blood conduit is arranged in parallel by at least two covered stents, one at a time assembled by the operator. The parallel blood conduits can each be provided with one or more side branches. Alternatively or in addition, a blood conduit in the form of a covered stent can be provided which does not have a lateral side branch, which then provides a straight blood flow path in parallel with a covered stent having, for example, one or more lateral side branches.

[0112] The parallel arrangement of the covered stents has several advantages. The repositioning of one of the plurality of parallel covered stents is easier than the repositioning of a single covered stent covering the entire blood vessel with a plurality of side branches. It is easier to implant a plurality of parallel covered stents with one or a few branches sequentially than one large covered stent with many branches. The proximal and distal ends of the covered stents 300, 310, 320 do not have stent insertion into the blood vessel tissue wall. Thus, the mechanical stability and attachment are better controllable with respect to the anatomical structure, especially if it is weakened at a site such as an aneurysm. This is an advantage since the parallel covered stents 300, 310, 320 can better adapt to the motion of the blood vessel. With reduced contact, the risk of damaging the tissue blood vessel is less, which has a positive effect on the long-term implant stability of the modular system. Since the rotational and longitudinal position is adjustable during the operation, the surgeon can easily adapt to the anatomical structure at the time of implantation. Aortic clamps are not needed, heart standstill is avoided, side effects for the patient are reduced, the operation is faster, and the patient risk is reduced. Since the diameter of each parallel covered stent 300, 301, 320 is smaller than the diameter of the blood vessel in which they are implanted, a distance to the side branches of the covered stent main lumen can be provided. This in turn allows a guiding clearance of the covered stent with respect to the side branch blood vessel orifice. Thus, the positioning of the side branches of the covered stent with respect to the orifice is less important than in known systems. When implanting a side blood vessel from a main blood vessel, compensation can be made due to the distance between the side branch of the covered stent and the orifice of the side blood vessel orifice, for example by bending the side branch and / or by bending the extending covered stent 600 without kinking the latter mentioned one or both.

[0113] The modular covered stent system also comprises a second type of main blood vessel covered stent 400, 430, wherein at least two upstream inlet branches are collected in a downstream outlet. The inlet branches can be interconnected with the distal outlet of one of the two covered stents, for example as shown in the covered stent types 300, 310, 320 as shown in Figure 1 and 2

[0114] Starting from the top of the system 100 as shown in Figures 1-2 the first covered stent 200 with three legs is shown. This module is first implanted on the guide wire 20.

[0115] It should be noted that the covered stent modules are delivered in a specific order, starting with the three-legged covered stent 200 in the ascending aortic arch. Further covered stent modules are then delivered to the target site until the entire system is implanted. This is done in a very efficient and advantageous manner.

[0116] For example, when the three-legged covered stent 200 is deployed and first implanted in the ascending aortic arch of all modules. This can be done with the guide wire 20, for example in the femoral access method. The other components can then be connected to the legs 201, 202 and / or 203.​

[0117] For example, the covered stent 600 can be delivered through a delivery catheter to the first leg 201, the delivery catheter being slid along the guide element 10 to or towards the connection point 11, for example to reference Figure 8 in a described manner. This covered stent 600 can then extend the blood flow into the first neck side vessel as Figure 2 shown. The covered stent 600 is a covered stent without orifices for the side vessels. The extension stent implant 600 is configured to fit proximally and fluid-tight connect to the distal part at the orifice of the first leg 201. The connection can be made in overlap in a suitable manner and by suitable means known in the art of connecting stent implants to each other in order to provide a communication passage for liquid through the target blood vessel.

[0118] Thus, the delivery can be provided in two steps. First, the side branch 3 is deployed. Then the side vessel covered stent 600 is deployed through the dilated side branch 3. The side vessel covered stent 600 is then fixed. The whole prosthesis is flexible until the side branch is finally cannulated, i.e. the side branch covered stent 60 is deployed and thus "locked" in place.

[0119] During the delivery of the covered stent 600, the two remaining legs 202, 203 are not obstructed and ensure blood flow through the aortic arch during the implantation process, which is an important advantage.

[0120] The guide element 10 also extends inside the third leg part 203. This means that, on the same guide element 10 and transfer catheter as the covered stent 600 is delivered to, the covered stent 300 with side branch is deliverable.

[0121] The initial guide wire 20 used to deliver the three-legged covered stent 200 to its target site is used to deliver and connect the covered stent 300 to the second branch leg 202.

[0122] The position of the three-legged covered stent 200 is preferably marked with a reference marker 21, which can be seen during imaging by, for example, MRI, CT or X-ray. Thus, a shortened radiation time and dose can be provided.

[0123] When the guide element 10 is extended from the first leg 201, the modular covered stent can be positioned with all three legs and interconnected at the orifices of the three legs. No additional navigation, search or probing by the surgeon is needed, thus reducing the radiation time and dose.

[0124] The guide element 10 is used to guide subsequent covered stents along them so that the subsequent covered stents can be connected to the previously implanted caged stent.

[0125] Additionally, or alternatively, the navigation element 20, e.g. a guidewire, is used instead of, or together with, one or more of the guide elements 10 to guide all or almost all of the covered stents of the system 100 to their target sites.

[0126] Next, the system 100 comprises, in the proximal direction, downstream of the aorta, two covered stents 300, each having one side branch, which are positioned in the aortic arch 502 at implantation. The two covered stents 300 are guided by the guide elements 10 and the guidewire 20, respectively. These modular covered stents 300 will be described in more detail below, e.g. with reference to Figure 5a 、 6 , 7, 8, 10, 11, 14, 15, 17, 19 and 20. Each covered stent 300 is distally connected to a leg 202, 203 of the three-legged covered stent 200. The side branch outlet is preferably expandable and, at expansion, in fluid communication with the carotid vessel. A further covered stent 600 is also connected proximally thereto, respectively, extending into the remaining two carotid vessels (see Figure 2 ). The delivery of these further covered stents 600 can be guided by fiducial markers (not shown) by guidewire and contrast feedback, and / or the guide elements 10 can be connected to the branches (see Figure 8 ), facilitating the delivery of the further covered stents 600 into the respective carotid vessels through the orifice of the side branch of the covered stent 300.

[0127] The delivery and extension of each covered stent 300 is performed in sequence. At delivery of the first of these two units 300, the other leg of the three-legged stent 200 is unobstructed and ensures blood flow through the aorta. Moreover, when the extension is delivered into the carotid vessel, blood flow in the aorta downstream and in the carotid vessels is not interrupted during the procedure.

[0128] When the two covered stents 300 are connected to each other and delivered, the parallel flow through the aorta provides the required sufficient blood flow due to the high ratio of lumen diameter to (healthy) aortic diameter.

[0129] Due to the parallel arrangement of the multiple covered stents 300, the orifice of the side branch can be located at a distance from the target site vessel ostium, the exact position relative to each other (ostium / orifice) is less important than with known covered stents. Flexibility is provided without the risk of kinking, with or without extension covered stents 600.

[0130] Then, downstream of the aorta, a double leg covered stent 420 is implanted / provided next in the downstream aortic direction and branches the blood flow to two proximal legs from a distal common lumen and orifice which can be connected with the proximal orifice of the previously implanted distal covered stent 410. The guiding element 10 extends inside the first leg. The guidewire 20 extends inside the other leg. The double leg stent is delivered in a delivery catheter which can be the same as the delivery catheter used for delivery of the previously distally delivered module.

[0131] Another covered stent 410 without side branches or legs is distally interconnected to the proximal orifice of the covered stent 400. The additional covered stent 410 is delivered over the guiding element 10 and the guidewire 20 which both extend inside the covered stent 410 through one of its distal legs. In case the covered stent 300 comprises one or more guiding elements 10 which were previously used for insertion of the extended covered stent into the carotid vessel, these one or more guiding elements 10 will also pass through the lumen of the covered stent 410.

[0132] The overlap of the covered stents 400, 410, 420 can be adjusted during implantation to adapt to the aortic anatomy of the patient.

[0133] Next in the downstream aortic direction a double leg covered stent 420 is implanted / provided and branches the blood flow to two proximal legs from a distal common lumen and orifice which can be connected with the proximal orifice of the previously implanted distal covered stent 410. The guiding element 10 extends inside the first leg. The guidewire 20 extends inside the other leg. The double leg stent is delivered in a delivery catheter which can be the same as the delivery catheter used for delivery of the previously distally delivered module.

[0134] Finally, at the bottom of the figure, two covered stents 310, 320 are shown, each with two side branches 3. Below reference is made to Figure 5a and 5b These two covered stents 310, 320 are described in more detail.

[0135] The first covered stent 310 is delivered over the guiding element 10 (the catheter is slid over the guiding element 8 to the leg portion of the covered stent 420). Additional delivery catheters can also be used for this purpose, see for example Figure 8The described differs in that the guiding element runs through the first covered stent 310 all the way. One or more additional guiding elements 10 can be attached to one or more side branches of the first covered stent 310 for delivery of an extended covered stent 600 extending into a side vessel, see Fig. 6 when implanted. Figure 2 .

[0136] The second covered stent 320 is delivered over a guidewire 20. A delivery catheter is again used for this purpose, as described above. Another guiding element can be connected to one or more side branches of the second covered stent 320 for delivery of an extended covered stent 600 extending into a side vessel, see Fig. 6 when implanted. Figure 2 .

[0137] The proximal ends of the two covered stents 310, 320 are interconnected to the two distal legs of the double leg covered stent 430, thereby providing a liquid path. The guidewire 20 and the guiding element 10 are passed through the covered stent 430 accordingly.

[0138] As described above, the system 100 is thus positioned as shown in Figure 2 .

[0139] In one embodiment, a method of interconnecting a plurality of covered stents is provided, which can be performed in vivo and / or ex vivo.

[0140] In one embodiment, the covered stents of the system 100 are sorted and placed in the correct order for assembly before assembly and / or during assembly. In one embodiment, and if assembled during implantation, multiple catheters 30 can be used as described and needed. The components of the system can be provided as a kit with appropriate numbering to facilitate implantation by the surgeon. The kit components and composition can be computer plant prior to the implantation procedure. Software can be provided to support the surgeon and / or clinical staff in performing the procedure. The surgeon can plan the procedure in advance. The order of components can then be suggested by the software during the implantation procedure, preferably with numbers in the kit components and procedure steps. Quality assurance can be provided by software feedback of used components and performed steps. X-ray images and time stamps and other medical device measurements or input data can also be saved. The procedure can thus be performed and documented simultaneously and efficiently.

[0141] Although not shown in the figures, the system 100 can be provided with a control unit for controlling the delivery of the covered stents 310, 320, 430, 600, see Fig. 6. Figure 1Further navigation elements 20 and / or guiding elements 10 can be provided for navigating the side branch 3 and aligning the side branch 3 with the branch vessel, as explained, but are not shown in the figures. In order to more easily see which navigation element 20 or guiding element 10 reaches a certain covered stent, leg or side branch, each navigation element and guiding element is labeled in one embodiment.

[0142] The modular covered stents as described in the system 100 will now be described in more detail. As described above, the modular stents can be arranged differently in other systems than the one shown in the figures. Some modular covered stents can be provided separately for connection to known units, or separately, depending on the target site, treatment needs and / or patient history.

[0143] Figure 3 A covered stent 200 is shown with three legs 201, 202, 203, and navigation elements 20 and guiding elements 10 entering from the suture to facilitate navigation to all three legs. Figure 3 and Figure 8 An embodiment is shown of how one or more (one shown) guiding elements 10 (e.g. sutures) pass through a covered stent during implantation of the system 100.

[0144] Three legs 201, 202, 203 are provided for connection to three aortic arch side vessels: one into the carotid artery, and two through passages with side branch vessels connected (when assembled). The three legs 201, 202, 203 can have different lumen diameters and lengths. Overlapping covered stents 300, 600 can be selected during implantation surgery according to patient anatomy.

[0145] Pre-attached guiding elements 10 extending into one leg (203) and another leg (201) allow direct cannulation of the side vessels. All side branches are directly accessed by the prosthesis, and there is no difficulty in positioning the side branches with the open legs of such implants. Navigation has been difficult to achieve so far due to the length of the delivery catheter, which the operator does not usually have a sense of aiming at the side vessels. Furthermore, the pulsatile blood flow during surgery and other procedural difficulties of side branch cannulation are less relevant with known covered stents. The difficulty of 3D to 2D visualization is avoided, less X-ray dose is required, the time of the procedure is significantly reduced, and patient risk is reduced.

[0146] The guiding elements 10 are used to guide additional covered stents into the connection position, so that the covered stents can be connected together into the system 100 of covered stents. More information about Figure 8 can be found below.

[0147] In the system 100 as Figure 3In the embodiment shown, the navigation element 20, here a guidewire, is inside and through the three leg covered stent 200 via the legs 202. During implantation of the system 100, the navigation element 20 is inserted into the vessel far enough so that any covered stent can follow the navigation element 20 to the desired target location.

[0148] In one embodiment, the covered stents are guided to their respective locations by sliding them along the navigation element 20 inside the delivery catheter. After release at the distal catheter tip, the covered stents are expanded to the appropriate location and implanted at the target site. A restraining member 8 can be provided.

[0149] Figure 3 Also shown is one or more guiding elements 10, for example sutures, that can be attached to the covered stent 200. In this figure, the sutures 10 are attached within the second leg 4 and extend through the third leg. As mentioned above, the guiding elements 10 have a similar purpose as the navigation element 20, namely to guide the delivery catheter to deliver the covered stents so that they can be connected to form the system of covered stents 100.

[0150] The operator can easily position the two legs and further guide the covered stents into either of the two legs. The operator can navigate a first additional covered stent 600 to the leg 201 through the guiding element 10, where the guiding element 10 is attached. When the first additional covered stent 600 is properly positioned and connected to the three leg covered stent 200, the operator can guide a second additional covered stent through the same guiding element 10 to the leg 203, where the suture exits proximally from the three leg covered stent 200. The navigation element 20 ensures that the operator can also position the third leg, as Figure 3 shown, and deliver the unit in this way as needed.

[0151] Generally, one advantage of using guiding elements 10 is that the sutures or wires are flexible and can be bent and manipulated as needed without breaking, such sutures replace or are in addition to the navigation element 20, for example a guidewire. The navigation element 20 is generally stiffer when it is a guidewire, so that it can exert a distal force from the operator, for example to push along the vessel from the puncture site. The catheter is then threaded over the guidewire and moved along the guidewire. The guidewire can then be removed from the catheter to deliver the unit through the catheter.

[0152] The flexible nature of the guiding elements 10 allows for example covered stents to be placed in the covered stent and / or navigated around for example corners in the vessel and / or side branch 3 and / or at locations around them. In some embodiments the guiding elements 10 run outside the delivery catheter lumen, the unit can be delivered through the delivery catheter lumen. Alternatively or additionally, the guiding elements can pass through the same lumen as the lumen used to deliver the unit.

[0153] Preferably, the distal end of the catheter 30 has a design such that the distal orifice extends beyond the attachment point of the distal end of the guide element 10. This can for example be provided by a longitudinal recess (not shown) in the catheter lumen wall, into which the guide element 10 fits. The distal end of the catheter 30 has its delivery orifice can then protrude beyond the attachment point 11, where the proximal end of the recess will be positioned when the delivery catheter 30 is pushed distally forward. The recess can be a longitudinal cut. The recess can have at least a V-shaped portion to allow the guide element 10 to be more easily captured or introduced into the recess. The catheter 30 can be slightly wiggled and / or rotated to allow the guide element 10 to enter the recess.

[0154] As previously explained with respect to the guide element 10, the position 11 is preferably provided with a marker, which is the position where the distal end of the guide element 10 is permanently or releasably connected to the covered stent, so that it can easily be seen during scanning, e.g. MRI, CT or X-ray. The connection point 11 serves as a stop unit for the guide element 10 to prevent tangible resistance by the surgeon and further distal advancement of the catheter 30 during the delivery process.

[0155] Figure 4 A covered stent 1 with a side branch is shown, and is an embodiment of a covered stent 300 with an exemplary system 100 of a side branch 3 Figure 1 and Figure 2 ).

[0156] The covered stent 1 has a main body 2, which is a covered stent, and a transverse side branch 3 connected to the main body 2. The side branch 3 protrudes from the main body 2 and is flexible and expandable. One advantage of the side branch 3 being flexible and expandable is that the side branch 3 can easily move in at least one dimension independent of the movement of the main body 2, so that the branch vessel can be found and it is easier to align for the side branch 3 to enter during implantation.

[0157] Figure 14A - is a perspective view, top view, side view and front view of an embodiment of a modular covered stent 300 with a single transverse side branch. Alternatively or additionally, the covered stent 1 can have more than one side branch 3, such as the covered stents 310, 320 shown in Figure 5a and 5b . The connection portion 3a provides the degree of movement of the branch 3. This improves long-term stability and can help to prevent clot formation.

[0158] Alternatively or additionally, the covered stent 1 has a plurality of legs and wherein at least one leg comprises a side branch 3. Thus, in one embodiment (not shown) the covered stent 1 has a plurality of legs and each leg comprises a side branch 3. In one embodiment, the side branch 3 is deflated, collapsed or folded and can look like Figure 3 a side branch 3. The collapsing can comprise a radial and / or longitudinal collapsed state allowing for a reduced cross section for delivery.

[0159] In one embodiment, the shape of the side branch 3 when collapsed can be dome shaped, or substantially hemispherical, see Figure 7 non-limiting embodiment. This makes the covered stent 1 safer during operation and / or navigation to the branch vessel than the presently known devices, as the side branch 3 has no sharp edges that can tear, rip or penetrate the branch vessel like the presently known devices. However, the branch vessel 3 is preferably only longitudinally expandable from the minimal body 2 and can be cylindrical, for example, as shown in Figure 1 , 2 , 4, 5a, 5b, 6, 8, 10, 11, 14, 15B, C, 20.

[0160] The side branch 3 is configured such that its shape can change to fit the branch vessel and allow further extension from the main body of the covered stent into the branch vessel with, for example, another covered stent or covered stent. Such an expanded state comprises inter alia a longitudinally expanded shape of the branch 3, for example Figure 4 , 5a , 5b, 9 and 10, 11, 14, 15, 17, 19, 20. As shown in Figure 6 the transition from the longitudinally collapsed state to the expanded state can be done by deployment, stretching, spring effect or other similar manipulation of the branch 3.

[0161] Figure 5a - b shows two embodiments of covered stents with more than one side branch in the expanded state. Figure 5a The covered stent 310 shown in Figure 5b has two lateral side branches 3 protruding from the same side.

[0162] For anatomical reasons, side branches of other structures are provided at the target site as needed. In one embodiment, the side branches 3 are distributed at any desired location on the main body 2. In one embodiment, the locations are based on the layout of the blood vessel into which the covered stent 1 is to be placed and its side vessels. Although not shown, the covered stent 1 can also have more than two side branches 3. The side branches can have an angle that is angled towards the side branch, i.e. an angle other than 90 degrees to the longitudinal axis of the main body, for example between about 30 or 45 degrees to less than 90 degrees.

[0163] As will be further explained below, the lateral side branch 3 can expand from a first protruding length or dimension to a second protruding length or dimension. This expansion can be independent of the expansion of the main body 2, or vice versa, the expansion of the main body 2 can be independent of the expansion of the side branch 3. This means that when the covered stent 1 with the side branch 3 is contracted or collapsed, in one embodiment, the side branch 3 can expand or unfold while the main body 2 of the covered stent 1 does not expand or unfold. In another embodiment, the main body 2 of the covered stent 1 can expand or unfold while the side branch 3 does not expand or unfold.

[0164] Since the side branch portion 3 of the covered stent 1 is flexible in some embodiments when extended, alignment with the side branch vessel can not be as important as with traditional covered stents. Due to this flexibility, navigation towards and / or into the side branch vessel is facilitated during implantation and through flexible implantation of the side branch 3, for example as shown in Figure 7 and 11 Some misalignment of the orifice of the side branch 3 at the main body of the covered stent 1 relative to the branch vessel orifice can be corrected by the path of the flexible laterally extending side branch 3. The blood communicating path of the side branch 3 can be extended by matingly engaging another covered stent or covered stent implant, which is interconnected at the distal end of the side branch 3 and extends into the side branch vessel.

[0165] Figure 6 A bottom view of an embodiment of a side branch is shown, which can self-expand from a contracted shape to an expanded shape. Figure 6 One embodiment of a covered stent 1 is shown. The covered stent discussed herein is in one embodiment self-expanding, or in another embodiment expandable by another device, for example an inflatable balloon, pusher unit, etc. Figure 6 Three different side branches 3 are shown in different expanded lengths.

[0166] The covered stent 1 has a main body 2 which is a covered stent and a side branch 3 connected to the main body 2. The side branch 3 protrudes from the main body 2 and is expandable and optionally flexible or is inclined at an angle relative to the main body longitudinal axis and / or arranged at such an angle when protruding from the main body 2. The side branch 3 has the advantage of flexibility and expandability that the side branch 3 can easily move in at least one dimension independent of the movement of the main body 2 so that the branch vessel can be found and more easily aligned for access to the side branch 3 during implantation.

[0167] In one embodiment, the covered stent 1 can have more than one side branch 3. In one embodiment, the covered stent 1 has a plurality of legs and wherein at least one leg comprises a side branch 3. Thus, in one embodiment, the covered stent 1 has a plurality of legs and each leg comprises a side branch 3. In one embodiment, the side branch 3 is deflated, collapsed or folded and in embodiments can look like a side branch 3 as shown in Figure 7 .

[0168] In one embodiment, the shape of the side branch 3 when collapsed is a dome shape or substantially hemispherical as shown in Figure 7 . The above allowed covered stent 1 is safer during operation and / or navigation to the branch vessel than the presently known devices since the side branch 3 does not have any sharp edges that tear, slit or penetrate the branch vessel as the presently known devices do.

[0169] The side branch 3 is configured such that its shape can change to fit the branch vessel and allow further extension from the main body of the covered stent into the branch vessel with e.g. another covered stent or covered stent. Such an expanded state includes inter alia a longitudinally expanded shape of the branch 3, e.g. as shown in Figure 4 , 5a , 5b, 6, 8, 9 and 10, 11, 14, 15, 17, 19, 20. As shown in Figure 10 , the longitudinally collapsed state to the expanded state can be accomplished by unfolding, stretching, spring effect or other similar operation of the branch 3.

[0170] In one embodiment, the expansion can be obtained by a spring effect of the covered stent 1 and / or the side branch 3 as shown in Figure 10 . In one embodiment, the expansion can reach an in-vivo equilibrium position.

[0171] The lateral side branch 3 is preferably integrally formed with the main body. In some embodiments, the side branch is provided with a spring that elastically self-expands the side branch 3 in the longitudinal direction of the side branch 3 without radial expansion. The spring can be a helical spring as shown in Figure 15BThe spring-like structure can be provided preferably to help the side branch to expand from the prosthesis body, e.g. perpendicular to the prosthesis body, or alternatively at an angle different from 90 degrees to the longitudinal axis of the body.

[0172] The covered stent 1 or the side branch 3 can comprise wires suitably arranged as a stent / support frame portion of the covered stent. In one embodiment, the wires can have a U-shape in the longitudinal direction of the covered stent. In another embodiment, the wires can be helically wound, as shown in Figure 10 In other embodiments, they can be arranged in a suitable pattern, e.g. a zig-zag pattern, etc.

[0173] In one embodiment, the wires can be interwoven wires with the covering. The wires can form a mesh, e.g. a knit pattern or a braid. The above wires can also be laser cut to form a spring-like pattern of the stent portion.

[0174] Alternatively or additionally, the wires or other expandable components of the present device can be made of a shape memory material. The shape memory effect of such wires can provide a change of shape, e.g. from a contracted to an expanded shape, by a known trigger such as temperature. Suitable materials include Nitinol, CrMo alloys, shape memory polymers, etc. The shape of the components of embodiments made of such materials can be provided by heat treatment. The components of embodiments of these materials can rely on elastic or super-elastic properties only (e.g. Nitinol) to change the shape from a contracted or compressed structure to an expanded, released structure.

[0175] When the covered stent 1 is made in a spring-like configuration, upon exiting the delivery catheter, it will spring out from the body of the covered stent, e.g. as described below with reference to Figure 10

[0176] Figure 7 It is shown how a covered stent with a collapsed or contracted side branch can be used to find a branch vessel. The volcano shape of the side branch 3 is only one embodiment as described above. A guidewire 20 is fed through the side branch, and a catheter is threaded over the guidewire. A delivery channel through the side branch is then provided.

[0177] The guidewire 20 can be previously guided through the guide element 10 to the target site, e.g. at the side branch 3, by a catheter 30. The catheter 30 can be retracted, and a different catheter threaded over the guidewire, thereby placed in position by guiding the catheter 30.

[0178] Figure 8 It is shown a covered stent 300 with a side branch 3, and a catheter with a guide fitting 9 for guiding the catheter 30 to facilitate navigation of the side branch.

[0179] In one embodiment, as Figure 8 ​As shown, the catheter 30 comprises a guide fitting 9 configured to travel over the guide element 10 and / or the navigation element 20 when guided to the side branch 3 by the guide / navigation element.

[0180] In this embodiment, the guide fitting 9 is a piece of tubing connected to the catheter 30. Alternatively, the guide fitting 9 is formed integrally with the catheter, for example by suitable extrusion of the tubular member of the catheter. The guide fitting can be formed as a lumen, and / or integral with the catheter wall. The guide fitting 9 can be formed integrally with the catheter, or alternatively, a separate element suitably attached to the guide element 10, for example by adhesion, welding or other mechanical attachment means. The catheter 30 can be a multi-lumen catheter having at least one lumen. Preferably, it is a dual lumen catheter. Figure 16 An embodiment is shown schematically in the middle. A first lumen 30a is provided for delivery of a unit deployable through a distal orifice of the first lumen. A second lumen as a guide fitting 9 is provided for passing over the proximal end of the guide element 10 towards its distal end and its point of attachment, as described above. The second lumen preferably has an orifice disposed proximally of the distal orifice of the first catheter lumen. In this way, the distal orifice of the first lumen can be distally positioned beyond the point of attachment of the guide element 10.

[0181] Alternatively or additionally, the guide fitting 9 comprises a loop, eyelet, snarl or ring for passing over the guide element 10. The inner diameter of the guide fitting 9 is matched to receive the outer diameter of the guide element 10, with a certain tolerance to avoid excessive friction between the two elements to slide along each other.

[0182] The guide fitting 9 is a unit for matingly receiving the guide element 10 therethrough for slidable movement along the guide fitting 9 to and from the distal end of the guide fitting, at which the guide fitting is preferably attached to the covered stent. The guide element 10 is configured to pass through the guide fitting 9 for slidable movement along the guide fitting 9. The guide element 10 is passed through, for example a multifilament thread such as a suture, thread, filament or wire, for example braided together to form a flexible guide element 10, suitably at the proximal end of the guide fitting outside the patient's body.

[0183] Alternatively or additionally, the guide fitting 9 can be a lumen of a dual (or multi) lumen catheter or any other suitable element configured to allow sliding over the guide element 10 and preferably not damaging the vessel or cavity in which it is used.

[0184] The guiding fitting 9 has preferably a distal end or opening which is arranged at a suitable distance, i.e. proximally, from the distal end of the catheter 30. In this way, the distal end or opening of the catheter 30 can be advanced further than the guiding fitting 9 when at the end position of the guiding element 10 and / or the navigation element 20, e.g. at a fixation point, e.g. a knot of a suture, where the guiding element 10 and / or the navigation element 20 are fixed distally to the covered stent, e.g. at the orifice or opening described and shown herein.

[0185] Thus, the guiding fitting 9 has a distal end or opening which is preferably arranged at a distance, i.e. proximally, from the distal end or distal opening of the catheter 30.

[0186] In this way, it is ensured that the distal end of the catheter 30 can be positioned distally of the connection point 11, e.g. delivered through the catheter's lumen into a side branch, e.g. a covered stent into a side vessel and assembly and interconnection with a main vessel covered stent, where the fixation point is located. In this way, the side vessel covered stent can be delivered to the correct position of the main vessel covered stent, i.e. the branch opening, with minimal X-ray dose, as the operator does not need 3D visualization.

[0187] In one embodiment, also in connection with Figure 8 the guiding element 10 is attached to the side branch 3. This allows implanting any other element, preferably a covered stent, to be easily delivered through the catheter 30 with the guiding fitting 9, e.g. connected to the side branch 3 or ejected from the side branch 3 with minimal effort and improved reliability and patient safety.

[0188] As Figure 8 shown, in some embodiments, the guiding fitting 9 is placed at a distance from the distal end of the catheter 30. One advantage of the guiding fitting 9 at a distance from the distal end of the catheter 30 is that the catheter 30 can subsequently reach a position further distally than the attachment position 11 of the guiding element 10. For example, if the guiding element 10 is attached at the side branch 3, the catheter can be further extended out through the side branch 3. This enables easy access to position and connect an extended covered stent 600, e.g. at the side branch 3.

[0189] The distal portion of the catheter 30, preferably distal of the distal end of the guiding fitting 9, can additionally or alternatively be curved, see Figure 8 This allows a desired exit angle of the orifice of the delivery catheter 30 at its distal end, e.g. substantially perpendicular with respect to the longitudinal axis of the main body 300.

[0190] However, in some embodiments, the distal portion or tip of the guiding fitting 9 can reach all the way to the distal end of the catheter 30. In any case, improved, advantageous minimally invasive delivery of the element through the side branch is ensured.

[0191] In one embodiment, as shown in Figure 9a , b, c, 10 and 11, 15 and 17, the covered stent 1 is provided with a constraining member 8, which can prevent the covered stent 1 from expanding before the constraining member is released to controllably expand the covered stent 1.

[0192] In one embodiment, the constraining member 8 is made of PTFE or A material. The constraining member 8 can be provided as a flat sheet, a fabric or a non-woven material, which is releasably arranged around the covered stent for delivery. Alternatively, any other suitable biocompatible material can be chosen for the constraining member, which can be inserted into the body and is easy to manipulate as well as protecting any blood vessels or lumens from the covered stent 1 during deployment.

[0193] Figure 9a - c shows an embodiment of a constraining member. For example, a self-expandable covered stent 200 can be provided with such a constraining member 8. By removing the constraining member, the covered stent controllably transitions from a collapsed state to an expanded shape.

[0194] In one embodiment, the removal of the constraining member 8 is done by simply pulling a wire, which then releases a seam that holds the sheet of the constraining member 8 arranged around the covered stent together. Pulling the release wire unfolds the constraining member along the seam, depending on the distance pulled on the wire. The constraining member is thus partially or completely unfolded, for example Figure 9a - shown in c. In one embodiment, more than one wire / seam is used to select the position where the constraining member 8 is removed to limit the covered stent and / or the side branch 3.

[0195] Alternatively or additionally, the constraining member 8 is configured to be partially removable, so that the expansion of the covered stent 1 and / or the side branch 3 can be individually selected. This is shown in Figure 9a , where the covered stent is fully constrained by the constraining member 8. In Figure 9b , the constraining member 8 is shown partially open, allowing the covered stent to partially expand. If desired, the partially expanded stent can still be repositioned.

[0196] Figure 9c The shown embodiment shows more than one constraining member 8 for limiting parts of the covered stent. Thus, each constraining member is provided to constrain a different part of the covered stent, here an embodiment of a three leg covered stent 200. In this way, the three legs are easily expanded individually, one at a time or simultaneously. In the same way, a covered stent 1 with a side branch 3 can be partially or fully expanded by releasing it from, for example, a constraining member around the main body 2 and another constraining member 8 around the side branch 3. An embodiment is explained below with reference to Figure 18 .

[0197] The contraction unit is delivered via a conduit. Figure 9a The delivery catheter is introduced to the target site and has a guide mating element 9 that slides along the guide element 10 as described above. The components shown in FIG9 (and other similar components) may include one or more guide mating elements 10 themselves, such as... Figure 3 As shown. The subsequent guiding element 10 is guided outward from the inside of the restraint member 8 from the covered stent (here 200) and further proximally towards the proximal end of the catheter outside the patient. Thus, as described herein, other elements can be advantageously delivered through the covered stent upon implantation.

[0198] In one embodiment, more than one thread is used to select the location where the restraint member 8 is removed from the covered support 1 and / or the side branch 3.

[0199] Alternatively or additionally, when attached to the covered support 200, the seam line of the restraining member is one of the guide elements 10. The guide element 10 is then attached distally to the covered support, for example in… Figure 3 In the middle, it extends proximally from the orifice of the covered stent 200. It then closes posteriorly, extending within the protective unit 8. Turning proximally back again, it provides a releasable seam. When pulled out and removed from the seam, the restraint member is released and further pulled back, leaving the guide element 10 as a catheter guide. The advantage of this synergistic guide element 10 and the seam of the protective unit / restraint member 8 is a reduction in the number of parts that need to be pulled out outside the patient, among other advantages. The restraint member 8 is configured to be partially removable, allowing for individual selection of the expanded covered stent 1 and / or the side branch 3. This in... Figure 9a As shown, the covered support 200 is fully constrained by the constraining member 8. Figure 9b In the middle, the restraint member 8 is partially opened, thereby allowing the covered support 200 to partially expand along its length.

[0200] Another embodiment is in Figure 9c As shown, more than one constraint member 8 is used to constrain different portions of the three-legged covered stent. In this way, for example, one or more of the three legs of the covered stent 200 can be easily expanded individually, one at a time, or simultaneously. In the same way, the covered stent 1 with side branches 3 can be partially or fully expanded by releasing, for example, constraint members around the body 2 and another constraint member 8 (not shown) around the side branches 3.

[0201] Figure 10 It shows how the sheath can be used to hold the covered stent in a contracted or closed manner, and how the covered stent can be released in a partially or fully controlled manner.

[0202] Figure 10how the covered stent 1 is first released from the constraining member 8 from one side (right side) as shown in the top (a) of Figure 10 As shown in the middle and bottom (b and c) of Figure 10 the covered stent 1 including the side branch 3 is then released. This is further illustrated in Figure 11 where the covered stent 300 is partially released from the constraining member 8 to allow the side branch 3 to easily adapt to the branch vessel. When the portion of the covered stent 300 including the side branch 3 is released from the constraining member 8, the side branch 3 is aligned with the branch vessel and then expanded into the branch vessel. The covered stent 300 is then fully released from the constraining member 8 as shown in the bottom of Figure 11 The covered stent 600 further extending into the side vessel is shown delivered and deployed as described herein.

[0203] Figure 11 An embodiment of the covered stent 1 is shown which can be used in a simple method of finding the branch vessel. The covered stent 300 is fully pushed out of the delivery device 30, e.g. a catheter, and the main body 2 of the covered stent 1 is expanded.

[0204] The side branch 3 is expanded in embodiments by being pushed outwardly and / or configured to expand by itself as disclosed above and shown in e.g. Figure 6 , 7 and 9.

[0205] Another pushing element (not shown) can be used to push the flexible side branch 3 outwardly in the desired direction to expand it from a collapsed or contracted state. This applies in case the side branch 3 is not self-expandable.

[0206] In case of a self-expandable side branch 3, it will expand radially outwardly from the main body and / or the removal of the constraining unit 8 once released from the delivery catheter (30).

[0207] For easier alignment with the branch vessel, the covered stent side branch 3 can be provided with a marker 21 as shown in Figure 3 When the side branch 3 is flush or aligned with the branch vessel, the marker 21 will be visible to the operator. By having only one marker at the side branch 3, the operator will more easily align the covered stent 1 to its desired position by using imaging means such as X-ray, instead of having to align in fluoroscopy with existing covered stents having multiple markers. The marker 21 is in embodiments any fiducial marker visible under ordinary types if used for healthcare or covered stent placement imaging means, e.g. MRI, X-ray, ultrasound, etc. The covered stent structure is generally difficult to see under e.g. fluoroscopy. The marker can e.g. be made of gold or similar material allowing good visibility in such imaging.

[0208] In one embodiment, the side branch 3 is collapsed or collapsed and restrained by a guiding element 10 such as a suture 10. The guiding element 10 is for example wrapped around the side branch 3 and releasably connected on the inside of the side branch 3 or otherwise attached to the side branch 3 so that it releasably collapses or collapses. Pulling the guiding element proximally then releases the side branch 3 from the collapsed state to the expanded state. The guiding element 10 remains in place to serve as a catheter guide.

[0209] In one embodiment, the covered stent 1 is aligned with the branch vessel by moving the main body 2 of the covered stent 1, as shown in Figures 9-11. In one embodiment, this is achieved by the covered stent 1 being only partially pushed out of the catheter 30 and / or partially released from the restriction device 8 as described above, so that the covered stent 1 can be moved by moving the catheter 30, or by for example advancing a wire, or otherwise moved, as shown in Figures 9 and 10. Preferably, the side branch 3 is self-expandable.

[0210] In one embodiment, the covered stent 1 is moved upwards until the markings 21 on the side branch 3 are aligned with the branch vessel. The covered stent 1 is then rotated until the side branch 3 enters the branch vessel. When the side branch 3 enters the branch vessel, the guiding element / for example the suture 10 is released, allowing the side branch 3 to expand into the branch vessel either by itself or by pushing outwardly.

[0211] In another alternative embodiment, the covered stent 1 is aligned with the branch vessel by navigating the main body 2 of the covered stent 1 and by navigating the side branch 3 of the covered stent 1.

[0212] Figure 15A is a perspective and cutaway view of a modular covered stent 300 with a lateral side branch in a delivery configuration. Figure 15B and 15C is a schematic view of the lateral side branch deployment of a modular covered stent 300 prior to release of the main body. Figure 15A is a schematic view of the lateral side branch deployment of a modular covered stent 300 prior to release of the main body. Figure 15B and 15CThe prosthetic delivery system is inserted and aligned with the side branch tip, close to or pointing to the side branch vessel. If needed, the position of the prosthetic can be adjusted, for example by means of the reference markers, optionally a guide wire can be used to find the side branch entry. The side branch outer sheath 8a is opened. The side branch outer sheath 8a can be fully opened to release the side branch prosthetic. The side branch prosthetic is fully expanded. Then the prosthetic body outer sheath 8 is opened to release the entire prosthetic. The dual lumen catheter 30 can be brought over the guide element 10 to bring another guide wire into the side branch for connection of the prosthetic delivery system. One of the lumens 9 will pass over the side branch guide element 10 to enter the side branch vessel. Once the dual lumen catheter 30 is in place, another guide wire will be introduced into the side branch through lumen 30a which can be freely moved up for a deeper access as described in more detail below with reference to the methods and procedures below.

[0213] Figure 17A is a perspective and cut view of the modular covered stent 300 with the lateral side branch in another delivery configuration. Figure 17B is a schematic view of the release of the body and lateral side branch of the modular covered stent 300. Figure 18 is a schematic view of a catheter tool for releasing the navigation unit from the extension of the lateral side branch.

[0214] The single layer outer sheath 8 covers the entire prosthetic / covered stent. The prosthetic exposure can be divided into three stages:

[0215] • First stage: The distal part of the outer sheath 8 is opened, releasing about 1 / 3 of the prosthetic body. The outer sheath 8 is slowly opened to release the first part of the prosthetic body. The position of the prosthetic can be adjusted.

[0216] • Second stage: The outer sheath 8 continues to open until the side branch prosthetic 3 is fully exposed. Once the correct position is found, the middle part of the outer sheath 8 is opened to release the side branch 3. The side branch 3 expands. The outer sheath 8 is further opened until the side branch 3 prosthetic is fully exposed and its position is adjusted if needed. To open the tip of the side branch prosthetic, the provided ring is released from the rod that holds it. Once the ring is released from the locking mechanism, the covered stent will expand elastically and / or by shape memory effect. The outer sheath 8 continues to open until the body 2 is exposed. Now, the surgeon can deliver the expanded covered stent 600 to the side branch vessel. Expanding a part of the prosthetic body 2 before initiating the side branch can help the surgeon to place the guide wire in the side branch vessel.

[0217] • Last stage: The sheath 8 is fully opened until the side branch prosthetic is in the side vessel.

[0218] Figure 18This is a schematic diagram of a catheter tool for releasing a navigation unit from an extension of a lateral branch. The distal end of the lumen of catheter 30 may include a distal unit for releasably attaching branch 3. Branch 3 includes, for example, an attachment device such as a loop 35. The attachment device, such as one or more wires or wire loops 35, is connected to the distal end of the prosthesis-side branch 3 and can be releasably secured to a locking portion 38. The locking portion 38 can, for example, move up or down relative to a stop unit, such as... Figure 18 The flange at the distal end is shown. The locking portion may include one or more rods or struts that are longitudinally movable and can engage with the ring 35. The locking portion 38, such as including rods or struts, can be releasably locked to the attachment device, as with the ring 35, for example, when moved upwards to the stop flange, as shown. The locking unit can be released from the attachment device by reversing the aforementioned rods in the opposite direction, thereby releasing branch 3 and allowing the catheter to be withdrawn proximally. A central space 39 is provided for a guidewire or covered stent to pass through. In this way, when connected to the branch, branch 39 can be moved by moving the catheter tip with the locking unit. Preferably, it is moved toward the branch vessel away from the body, but if necessary, it can also be configured to withdraw branch 3 toward the body to adapt to anatomical conditions. As described above, the catheter can be guided with the guiding element 10.

[0219] An example of the implementation of the lateral branch prosthesis 300 is as follows:

[0220] • The length of the third lateral branch of the implant is approximately 15 mm.

[0221] Figure 14 shows some other exemplary but non-restrictive measures.

[0222] Features of the preloaded guide element 10:

[0223] The guide catheter 30 is secured by a lateral branch, preferably at a location that facilitates manipulation of the catheter's orientation for appropriate engagement of the guide element 10. The connection point is, for example, on the distal medial side of the branch 3, allowing the guide catheter 30 to be advantageously navigated through the lumen of the branch 3 toward the lateral vascular orifice or lumen.

[0224] The preloaded guiding element 10 serves as a guide for the conduit 30, for example... Figure 16 The double-lumen catheter shown reaches the lateral blood vessel.

[0225] The preloaded guide element 10 is preferably configured to be easily unlocked from the prosthesis.

[0226] An embodiment of the visceral side branch 310 is as follows:

[0227] • The prosthesis lateral branch 3 can be configured to maintain a certain angle relative to the longitudinal axis of the main body 2, such as approximately 30 degrees or 45 degrees, to help the surgeon access the lateral vessel with catheter 30.

[0228] • the internal diameter of the side branch can be in the range of about 7 mm,

[0229] • the side branch prosthesis 3 is provided to allow for some degree of movement to allow for adjustment of the various angles of connection towards the side vessels.

[0230] Figure 12 Flowcharts showing two embodiments of a medical procedure are shown.

[0231] The method 700 comprises the steps of: 710 accessing a target site as a patient's blood vessel; 720 delivering a first covered stent inside the blood vessel at the target site by a delivery catheter, wherein the target site has a side branch blood vessel; 730 delivering a second covered stent to the first covered stent; 740 connecting the first covered stent to the second covered stent for providing blood flow to the side branch blood vessel. The delivery of the second covered stent comprises sliding the catheter 30 along the guide element 10 to a position inside the lumen of the side branch of the first covered stent; and expanding the second covered stent to connect to the first covered stent. The catheter 30 with the guide fitting 9 can be used to deliver the guidewire. Once the guidewire is in place in the side branch and extends far enough into the side vessel at the side branch, the catheter 30 can be retracted. The extended covered stent 600 can then be delivered to the side vessel over this guidewire.

[0232] Alternatively or additionally, a method 800 is provided. The second covered stent can have a side branch 3. The method comprises delivering the second covered stent to the side vessel through the side branch 3 of the first covered stent. The method 800 comprises the steps of: 810 accessing a target site as a patient's blood vessel; 820 delivering a first covered stent inside the blood vessel at the target site by a delivery catheter, wherein the target site has a side branch blood vessel; 830 expanding the side branch 3, 840 delivering a second covered stent to the first covered stent and through the side branch 3 to the side vessel; 850 connecting the first covered stent to the second covered stent for providing blood flow to the side branch blood vessel. As described above, the catheter 30 with the guide element 10 can be used between steps 830-840.

[0233] In a particular embodiment, the method comprises delivering and assembling the system 100 as described above, and has the final layout shown in Figure 1 and Figure 2

[0234] The method starts in an embodiment with a soft guidewire inserted into the patient's blood vessel. Using a soft guidewire ensures that no part of the blood vessel is damaged during the insertion. Furthermore, the soft guidewire can be bent, thereby navigating through the patient's blood vessel system to the target site, which in this embodiment is the ascending aorta. As described above, other target sites in the body can also be chosen as an alternative.

[0235] ​The first catheter is then inserted over a soft guide wire into the patient's blood vessels and navigated until it reaches the target site. Under the guidance of the first catheter, the harder navigation element 20 is then inserted into the catheter and from there into the patient's blood vessels.

[0236] The target site in this embodiment is the ascending aorta, where a three-legged covered stent 200 is subsequently positioned through a delivery catheter in the aortic arch. The delivery state assembled with other components in the aortic arch is shown in Figure 2 .

[0237] The three-legged covered stent 200 is then collapsed or folded to fit inside the first catheter 30 and pushed along it, the navigation element / guide wire 20 can extend inside the main part of the covered stent and protrude through one of the legs 201.

[0238] As mentioned above, the three-legged covered stent 200 is provided with a guide element 10 attached inside one of the other legs. In one embodiment, the position near or to the left of the aortic arch is preferred.

[0239] Each guide element 10 and navigation element 20 can be marked proximally at the end to facilitate identification. The proximally marked end is configured to be outside the patient's body during implantation.

[0240] Next, when in the correct position at the target site, the covered stent 200 is pushed out of the catheter 30 and allowed to expand or unfold completely or partially, as described above. The rotation is performed until the legs match the main blood vessels and the carotid artery branch vessels. And as mentioned above, this alignment can be performed in various ways.

[0241] Next, when the three-legged covered stent 200 is in place, the other modules of the system 100 can easily be built. As mentioned above, this can be done in several ways, and in this embodiment, two covered stents 1 with side branches 3 and covered stents 600 for extension into branch vessels are unfolded after the three-legged covered stent 200 as described above with reference to Figure 1 and 2 .

[0242] In the embodiment shown in Figure 1 and Figure 2 , the extension covered stent 600 is navigated via the guide element 10, which is attached inside one of the legs of the three-legged covered stent 200 and navigated through the three-legged covered stent 200 and positioned so that it can extend into the leg. Here, the covered stent 200 is expanded and connected to the leg in an overlapping manner.

[0243] Next, the first covered stent 300 with side branch 3 is slid into place along the guide element 10 and connected to the third leg 203. After or before being deployed along the guide element 10, the second covered stent 300 is slid along the guide wire 20 and connected to the second leg 202.

[0244] It is necessary to not stop the blood flow in the aorta or in the cardioplegia fluid with an aortic clamp. Due to the parallel arrangement of the covered stents 300, the blood flow through the aorta and the side vessels is not interrupted during the procedure.

[0245] When the covered stents are delivered, the side branch 3 is navigated into place at the same time with the covered stents and at least expanded towards the branch vessel. Next, any further extended covered stents can be inserted based on the desired need to further extend into the branch vessel.

[0246] Next, the covered stent 400 with two legs is moved in a collapsed state within the first catheter 30 along the guide wire 20 and the guide element 10. The covered stent 400 is oriented such that the legs are positioned towards the already connected covered stents 300. Each leg is guided along one of the guide element 10 and the guide wire 20 such that each leg can be guided into one of the previous covered stents 300 with side branch 3. When in place, the covered stent 1 is released from the catheter 30 and can be expanded.

[0247] Alternatively, the collecting covered stent 400 can be connected to the proximal end of the branch covered stent 300 before the connecting side branch and / or the delivery of the extended covered stent 600.

[0248] Next, a tubular covered stent 410 without legs or side branches is pushed into place through the catheter 30 and navigated and connected to the previous covered stent 400 in a similar manner, but now with the guide element 10 and the guide wire 20 both running inside. When making the interconnection of these stents, the length of the assembled prosthesis can be adjusted by the variable overlap of the covered stents chosen by the surgeon during implantation.

[0249] Then, a double leg covered stent 420 is connected to the tubular covered stent 1 in the same manner. The orientation of this double leg covered stent 420 is such that the legs are directed away from the covered stents already connected proximally upstream of the aorta. These legs are extended along the guide element 10 and the guide wire 20, respectively. When making the interconnection of these stents, the length of the assembled prosthesis can be adjusted by the variable overlap of the covered stents chosen by the surgeon during implantation.

[0250] After connecting the dual leg covered stent 420, the covered stent 310 with two side branches 3 is guided along the guiding element 10 through the delivery catheter in a similar way as the previously delivered covered stent 300. When the main body of the covered stent is in approximately correct position, further navigation of the side branches 3 is performed to be rotationally correctly directed towards the side vessels. Thus, the side branches 3 are aligned with and expanded into the branch vessels. At the distal end, the covered stent 310 is connected with one leg of the dual leg covered stent 420.

[0251] Then, the covered stent 320 with two side branches 3 and a further guiding member 10 or navigation element 20 is guided via the catheter 30, aligned with the branch vessels and connected to the second leg of the dual leg covered stent 420.

[0252] Finally, the last dual leg covered stent 430 is positioned and both legs are connected to the two covered stents 310, 320 with two side branches 3 in a similar way as described above by using the delivery catheter 30 and connecting along the guiding elements 10 and the guide wires 20, respectively.

[0253] When the system 100 is connected and completed, all remaining navigation elements 20 and catheters 30 are removed from the patient. The guiding elements 10 can be cut distally and the remaining length left in place, preferably for subsequent biodegradation.

[0254] In one embodiment, as shown in Figure 2 the complete system 100 is shown assembled and implanted within the aortic arch of a patient. It can be seen that the different covered stents 1 have been connected to each other and the side branches 3 have been extended into the branch vessels and further extended with covered stents 1.

[0255] Further proximal covered stent modules (not shown) can be provided and implanted, for example for iliac artery reconstruction or repair, for example connected to the proximal end of the covered stent 430.

[0256] Figure 13 A method for navigating a covered stent 1 into a branch vessel is shown. The method 900 comprises the following steps: providing a covered stent 1 as described above, 910, and navigating a lateral side branch 3 into a branch vessel by moving the lateral side branch 3, 920.

[0257] In one embodiment, this is performed by using an elongated navigation element 20 as described above. In one embodiment, it is performed using a guiding element 10 and a catheter 30 with a guiding fitting 9 as described with respect to Figure 8

[0258] ​The method can further comprise the step of expanding the lateral side branch 3 from the collapsed state into the branch vessel when the lateral side branch 3 is navigated to the desired position in the branch vessel. This can be done by navigating the covered stent 1 to align the side branch 3 with the branch vessel, then expanding the side branch 3 into the branch vessel, and finally expanding the rest of the covered stent 1 as described for example in Figs. 9-11.

[0259] In one embodiment, the method further comprises the step of interconnecting the expanding element at the lateral side branch 3 into the branch vessel for further extension into the branch vessel. The expanding element can be a covered stent 1.

[0260] Further embodiments of methods and procedures are given below:

[0261] A method for navigating a covered stent into a branch vessel is provided. The method comprises providing a covered stent 200, 300, 310, 320 and navigating a lateral side branch into or towards a branch vessel by moving the lateral side branch using a guiding element 10. The method can comprise expanding the covered stent delivered through the lateral side branch 3 from a collapsed state into the branch vessel when navigated to a position in the branch vessel. The method can comprise interconnecting an expanding element 600 at the lateral side branch into the branch vessel for further extension into the branch vessel, wherein the expanding element is preferably a covered stent.

[0262] A method for interconnecting a plurality of covered stents is provided. The method comprises providing a covered stent with a bendable guiding element connected at the outlet of a side branch. The method can comprise interconnecting a plurality of such covered stents, including sliding a catheter along the guiding element to the outlet of the side branch by means of a guiding fitting 9, and threading another covered stent through the catheter along the bendable guiding element for interconnecting the covered stents. The covered stents are preferably of the same size at the interconnection.

[0263] A medical procedure is provided, comprising 710 accessing a target site as a patient's blood vessel; 720 delivering a first covered stent through a delivery catheter inside the blood vessel at the target site, wherein the target site has a side branch vessel; 730 delivering a second covered stent to the first covered stent; 740 connecting the first covered stent to the second covered stent for providing blood flow to the side branch vessel, wherein the delivery of the second covered stent comprises sliding a catheter along a guiding element 10 to a position inside the lumen of the side branch of the first covered stent; and expanding the second covered stent to connect to the first covered stent.

[0264] A medical procedure is provided comprising 810 accessing a target site as a patient's blood vessel; 820 delivering a first covered stent inside the blood vessel at the target site through a delivery catheter, wherein the target site has a side branch blood vessel; 830 dilating the side branch 3; 840 delivering a second covered stent to the first covered stent and through the side branch 3 to the side blood vessel; 850 connecting the first covered stent with the second covered stent so as to provide blood flow to the side branch blood vessel.

[0265] Another embodiment of the delivery procedure is as follows:

[0266] 1. Insert the delivery system into the patient through the introducer sheath.

[0267] 2. Open the outer sheath 9 and remove from the proximal end of the prosthesis towards the direction of the side branch prosthesis. Keep open until the side branch prosthesis is released and fully deployed.

[0268] 3. Stop opening until the side branch prosthesis is fully exposed.

[0269] 4. Adjust the position of the prosthesis for initial matching.

[0270] 5. Insert the double lumen catheter 30 over the preloaded guiding element 10 and allow it to travel to the side branch prosthesis until it hits the end at the connection point 11.

[0271] 6. Insert an additional guidewire through the double lumen catheter 30 and allow it to protrude from the side branch 3.

[0272] 7. Optionally further adjust the position of the prosthesis.

[0273] 8. Once the position of the side blood vessel is identified and confirmed, advance the additional guidewire to secure the position.

[0274] 9. Once the additional guidewire is firmly resting in the side blood vessel, remove the double lumen catheter and deliver the connection prosthesis 600 by using the additional guidewire.

[0275] 10. Once the connection prosthesis 600 is in the side blood vessel and fully inflated, remove the remaining part of the outer sheath 9 of the previous prosthesis, fully releasing it.

[0276] 11. Unlock the guiding element 10 from the side branch prosthesis and remove all guidewires and delivery system from the patient's body.

[0277] The present disclosure has been described above with reference to specific embodiments. However, other embodiments than the above described are equally possible within the scope of the present disclosure. Different method steps than those described above can be provided within the scope of the present disclosure, and the method steps can be executed in a different order than that described above. The various features and steps of the present disclosure can be combined in other combinations than those described above, and the methods of the present disclosure can be executed in other environments than those described above. The scope of the present disclosure is only restricted by the appended patent claims.

Claims

1. A delivery conduit for delivering and deploying a second covered stent, the second covered stent being connected to a first covered stent (1), the conduit having: - A delivery lumen having a distal orifice for delivering and deploying the second covered stent at a target location of a side branch (3) of the first covered stent (1); and - A guide fitting (9) configured to receive a guide element (10) at a connection point distally attached to the side branch of the first covered support, the connection point defining a stop unit; in, When the guide element (10) is received in the guide fitting (9), the conduit is configured to slide along the guide element (10) to the orifice of the side branch for delivery and deployment of the second covered stent through the delivery lumen of the conduit, wherein the guide fitting (9) for receiving the guide element (10) has a distal end positioned at a proximal distance from the distal orifice of the delivery lumen such that when the distal end of the guide fitting (9) engages the stop unit of the connection point, the delivery lumen extends beyond the connection point to deliver and deploy the second covered stent at the target location of the side branch (3).

2. The delivery conduit according to claim 1, wherein, The distal end of the delivery lumen is pre-bent to conform to the shape of the side branch of the first covered stent.

3. The delivery conduit according to claim 1, wherein, The catheter is a multi-lumen catheter, and the guiding fitting (9) is a first lumen different from the second lumen of the catheter for delivering the extended stent implant (600), and the first lumen has a distal opening located at the catheter proximal to the distal opening of the second lumen.

4. The delivery conduit according to claim 3, wherein, The sheath of the second lumen of the catheter is bent at least a portion of the distance.

5. The delivery conduit according to claim 1, wherein, The guiding element is permanently or releasably connected at the connection point to the interior of at least one of the side branches (3).

6. The delivery conduit according to claim 1, wherein, The connection point is at the distal opening of the side branch (3).

7. A system comprising a delivery catheter and a covered stent, the covered stent comprising: -Main body (2), - At least one branch (3) connected to the main body (2), including one, two or three branches, and characterized in that At least one bendable and / or flexible guide element (10) is permanently or releasably connected at a connection point at the distal orifice of the branch (3) to the interior of one of the at least one branch (3), and the guide element (10) is proximally disposed inside the body (2), passing through and along the proximal portion of the body (2), and extending proximally through the proximal opening of the body (2), or through the leg (203) of the covered stent (1), the guide element (10) being received by a guide fitting (9) of a delivery conduit for delivering another element, such as another covered stent, to the at least one of the branches (3) at the connection point, and the guide element (10) being configured to guide the delivery conduit through the body (2) above the guide element (10) toward the distal orifice of the branch (3), wherein, The guiding element (10) is arranged via the guiding mating member (9) for delivering the second stent implant (600) via the delivery conduit to the target site of the branch (3), wherein the second stent implant is preferably an extension stent implant (600).

8. A covered stent, the covered stent comprising: Lateral side branches extending from the main body of the support, The lateral branch includes a support frame and a frame pattern with an asymmetrical design to improve the retractability of the support, wherein the frame pattern has areas without the support frame.

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