Apparatus and method for creating an anastomosis - Patent application

Abstract

The device comprises a stent (1) expandable from an undeployed configuration (2) for delivery to a target site for anastomosis, and a deployed configuration to form a temporary stent anastomosis (201) having a through channel (5). Magnetic attraction between the first and second portions (11, 12) around the through channel (5) induces the formation of a permanent magnetic compression anastomosis (202) that biologically replaces the temporary stent anastomosis (201). The device may be particularly suitable for use in the digestive system, optionally the digestive tract.

Description

[Technical field]

[0001] The present invention relates to the field of forming an anastomosis between body lumens. In one non-limiting aspect, the present invention relates to forming an anastomosis in the digestive system, preferably the digestive tract, of a patient. [Background technology]

[0002] An anastomosis is a surgical cross-connection or bridge between two different sections of a body lumen. The digestive tract is a luminal pathway in the body from the esophagus to the anus. Anastomoses formed along or anywhere in the digestive tract are a form of therapy used to treat digestion-related problems such as diabetes, obesity, bowel disease and obstruction. Anastomoses can be formed by open surgical procedures, but achieving anastomoses equally effectively by less invasive procedures such as laparoscopic, endoscopic, or intraluminal remains a significant technical challenge. See, for example, the devices proposed in US Patent Application Publication No. 2010 / 191264, US Patent Application Publication No. 2013 / 110141, and US Patent Application Publication No. 2020 / 323550. Summary of the Invention [Problem to be solved by the invention]

[0003] It would be desirable to address and / or mitigate such problems and / or facilitate less invasive anastomosis formation. [Means for solving the problem]

[0004] Aspects of the invention are defined in the claims. Additionally or alternatively, an aspect of the invention provides an apparatus for forming an anastomosis of two body lumen walls, optionally of the digestive system, optionally the digestive tract.

[0005] The device has an undeployed configuration for introduction to a target site for anastomosis and a deployed configuration for implantation.

[0006] The device comprises a stent expandable from an undeployed configuration to a deployed configuration to form a stent anastomosis, in which the stent is secured against a wall and / or provides a through channel, for example for fluid communication between two body lumen sections.

[0007] In a deployed configuration of the device, the first and second portions of the device are positioned laterally outward of the through channel in an annular arrangement, the first and second portions being magnetically attracted to one another to form a compression anastomosis about the through channel of the stent.

[0008] In addition to or instead of the first aspect above, a second aspect of the invention provides an apparatus for forming an anastomosis of two body lumen walls, optionally of the digestive system, optionally the digestive tract. The apparatus comprises a stent expandable from an undeployed configuration for introduction to a target site for the anastomosis to a deployed configuration for implantation to form a stent anastomosis. In the deployed state, the stent is secured against the walls and / or provides a through channel, e.g. for communication of bodily fluids between the two body lumen sections.

[0009] In the deployed configuration of the stent, the device is also configured to apply pressure by magnetic attraction between the first and second portions of the device to induce the formation of a permanent compression anastomosis surrounding and laterally outwardly directed through the through channel of the stent. For example, the first and second portions are positioned laterally outwardly of the through channel of the stent. The first and second portions may optionally surround the periphery of the through channel at opposing ends of the through channel.

[0010] In addition to or instead of the first and / or second aspects above, a third aspect of the invention provides an apparatus for forming an anastomosis of two body lumen walls, optionally of the digestive system, optionally the digestive tract. The apparatus comprises an expandable stent having a through channel. The apparatus is configured to form a stent anastomosis at a target site and form a compression anastomosis by magnetic compression of wall tissue around the stent anastomosis.

[0011] For example, the stent is expandable from an undeployed configuration for introduction to a target site for anastomosis and a deployed configuration for forming a stent anastomosis, In the deployed configuration, the device is further configured to induce a compression anastomosis around the stent anastomosis via magnetic attraction between a first portion and a second portion of the device.

[0012] Additionally or alternatively to the above first and / or second and / or third aspects, a fourth aspect of the invention provides an apparatus for forming a magnetic compression anastomosis of two body lumen walls, optionally of the digestive system, optionally the digestive tract. The apparatus comprises a first part and a second part that is magnetically attracted to the first part to induce a compression anastomosis in the region of the wall. The apparatus comprises or further comprises an expandable stent for providing a stent anastomosis in said region of the wall to define a temporary through channel until completion of the compression anastomosis.

[0013] In each or any of the above embodiments, in use, the (eg, permanent) compression anastomosis caused by magnetic attraction can biologically replace the stent anastomosis.

[0014] The device has the advantage that the expandable stent can provide a working anastomosis immediately after implantation and can further induce the formation in the body of a permanent compression anastomosis. The stent may be considered to provide an initial or temporary anastomosis. Upon implantation, the medical practitioner can verify the correct placement and function of the stent anastomosis. The stent anastomosis can also provide immediate relief and / or cure of the medical condition being treated. The stent itself can provide a well-defined, self-supporting through channel that is not subject to the risk of stenosis due to tissue growth and healing around the anastomosis. The stent does not need to provide a durable anastomosis, as the compression anastomosis typically forms around the stent within a period of weeks or months (e.g., typically 3-4 weeks). Not requiring the stent to be highly durable provides considerable design freedom and cost benefits. The compression anastomosis is formed by necrosis of the compressed tissue of the two walls pressed together by magnetic attraction, and tissue healing around the necrotic tissue, resulting in an integral and / or permanent bond.

[0015] Once healing has reached an appropriate stage, the necrotic tissue can detach from the surrounding tissue wall. In some embodiments, the necrotic tissue and attached stent can move away, e.g., naturally or assisted by a subsequent procedure to remove and / or extract and / or retrieve the device. In some embodiments, the stent can be configured to remain trapped in the wall, e.g., along with the necrotic tissue.

[0016] By way of example, the target site for the anastomosis may be between the wall of the stomach and the wall of the jejunum to form a gastrojejunal anastomosis that bypasses the duodenum and optionally a portion of the jejunum. An example of an alternative target site is between the wall of the ileum and the wall of the jejunum to form an ileo-jejunal anastomosis.

[0017] The use of an expandable device and / or an expandable stent allows the installation procedure to be performed minimally invasively, optionally laparoscopically and / or endoscopically and / or intraluminally.

[0018] The stent may self-expand from a non-deployed configuration to a deployed configuration and / or may be forcibly expanded (e.g., by an expansion balloon or other deployment device that applies a deployment force to the stent). A self-expanding stent may be made of or include, for example, a shape memory material, such as a shape memory metal alloy and / or a shape memory plastic. Suitable alloys may include nickel and titanium (e.g., NiTi alloy and / or Nitinol), optionally in combination with cobalt (e.g., NiTiCo). Whatever the material, in the deployed configuration, the stent preferably provides a self-supporting structure, and optionally provides a frame-like and / or lattice-like and / or mesh-like structure. The stent may be monolithic or may be made of one or more elements that are directly (e.g., by at least one connector or fastener) or indirectly (e.g., by braiding or weaving) joined together.

[0019] In some embodiments, at least one, and optionally both, of the first and second portions are configured to move by swinging and / or articulating and / or bending laterally outward when the device expands from the undeployed configuration to the deployed configuration.

[0020] In some embodiments, at least one of the first and second portions, and optionally both, are configured to move from a position adjacent to each axial end of the stent to a spaced position between the axial ends when the device expands from the undeployed configuration to the deployed configuration.

[0021] In some embodiments, at least one, and optionally both, of the first and second portions are configured to move closer to the other of the first and second portions when the device expands from the undeployed configuration to the deployed configuration.

[0022] In some embodiments, at least one of the first and second portions, and optionally both, include a plurality of magnets.

[0023] In some embodiments, at least one of the first and second portions, optionally both, comprises a pressure element in the form of a closed loop for compressing tissue in the wall to induce tissue necrosis when the first and second portions are magnetically attracted to each other. The pressure element may comprise a flexible filament, e.g., a polymer filament. Alternatively, the pressure element may comprise a frame element of the respective portion.

[0024] In some embodiments, the magnets are connected by frame elements configured to collapse circumferentially about the stent when the device is in an undeployed configuration.

[0025] In some embodiments, at least one of the first and second portions, optionally both, are configured to arrange magnets in multiple longitudinally offset circumferential rows in the respective portions when in the undeployed configuration and in a substantially single circumferential row in the deployed configuration. Each portion may optionally comprise connecting elements connecting the magnets, the multiple rows of magnets being connected by a zigzag pattern of connecting elements when in the undeployed configuration.

[0026] In some embodiments, at least one of the first and second portions, optionally both, includes a forming structure including radial elements and a circumferential loop structure with connecting elements connecting between the radial elements of the forming structure. The magnets may be supported in a circumferential direction by alternating forming structures and connecting elements.

[0027] Additionally or alternatively to any of the above, the magnets of the first and second portions may be substantially aligned with the other portion, at least in the deployed configuration.

[0028] In some embodiments, at least some of the magnets carried on the same part are configured to repel each other.

[0029] In some embodiments, in the deployed configuration, at least one, and optionally both, of the first and second portions have a profile that includes a convexly curved portion about the through channel, resulting in a concavely curved portion radially outward of the convexly curved portion. Optionally, the concavely curved portion merges into a substantially flat perimeter portion.

[0030] At least a portion of the stent (e.g., the connector) may be made of a material that weakens over time, e.g., a bioabsorbable material, such that at least a portion of the stent loses strength. Additionally or alternatively, the stent may be configured to change configuration from the deployed configuration to the post-deployed configuration. For example, as a portion of the stent weakens, the stent itself or another member of the device (e.g., an elastic cover) may cause the stent to deform to the post-deployed configuration. In the post-deployed configuration, the device may have, at least in part, a more streamlined shape, e.g., to facilitate passage of the device through the intestine to be evacuated. For example, the post-deployed configuration may be elongated, or elliptical or diamond-shaped.

[0031] The post-deployment configuration may be accomplished by other techniques. For example, the stent may be segmented into first and second segments, which may at least partially deform (e.g., bend and / or at least partially fold) after the device separates from the tissue wall. The segments may be at least partially defined by structural discontinuities and / or structural gaps.

[0032] However the stent is configured, transformation to the post-deployment configuration may be accomplished by external influences, such as, for example, when passing through the intestine or anus, and / or possibly under the influence of the device itself. Such influences may result, for example, from magnetic attraction between the magnets, and / or the stent tending to reshape itself to the post-implantation configuration, and / or from an elastic covering (not shown) of the stent exerting forces tending to deform the stent.

[0033] In some embodiments, the (eg, smallest) lateral dimension (eg, diameter) of the through channel when the stent is in a deployed configuration is greater than the lateral dimension (eg, diameter) of the stent and / or device when in an undeployed configuration.

[0034] The magnetic attraction may be provided by one or more magnets, optionally carried by or incorporated within the stent. Providing one or more magnets with the stent allows, for example, the magnet and the stent to be introduced together using a single delivery device. The magnets may be or may include a plurality of individual magnets carried by the stent. The magnets may be provided to allow the stent to collapse to its undeployed configuration and expand to its deployed configuration. In some embodiments, the magnets may be spaced around the stent, for example spaced apart by a circumferential distance at least equal to the circumferential (or tangential) dimension of the magnets. In other embodiments, the magnets may provide a more continuous or substantially continuous arrangement, for example, such that the spacing between adjacent magnets is less than the circumferential (or tangential) dimension of the magnets.

[0035] In some embodiments, the stent carries a pressure element, e.g., a flexible filament adjacent to a magnet. The flexible filament or other pressure element may be configured to provide a substantially closed loop shape, possibly in combination with the magnet or collectively, such that pressure is applied to the body tissue around a continuous closed loop. The flexibility of the filament allows the stent to collapse to a non-deployed configuration and expand to a deployed configuration. The filament may be made of or include a polymer and / or a shape memory material (e.g., a shape memory alloy as described above).

[0036] In some embodiments, the stent and / or the cover of the stent is configured to provide a generally atraumatic exterior surface or shape when in a deployed (and / or post-deployed) configuration to facilitate passing the device outside the body, e.g., when expelled through the anus. For example, the device may have a generally rounded toroidal shape. Any sharp edges of the device and / or stent may be configured to face the interior of the structure. Additional struts may be provided to bridge portions of the stent having a steep profile.

[0037] A further aspect of the invention relates to assisting the biological process by which compression anastomoses are formed.

[0038] In addition to or in place of any of the above, a further aspect of the invention provides an apparatus for forming an anastomosis of two walls of a patient's digestive system, optionally the digestive tract, the apparatus having an undeployed configuration for delivery to a target site for the anastomosis and a deployed configuration for implantation. a first structure including a first and a second portion for compressing a first tissue section of the wall about a substantially closed loop shape between the first and second portions to cause necrosis of tissue in the first section; a second structure disposed laterally (e.g., radially) outward of the first and / or second portions of the first structure for compressing tissue in a second tissue section laterally outward of the first tissue section with a compressive force less than that of the first structure, the second structure being optionally configured to press the tissue together without causing necrosis; Equipped with.

[0039] Additionally or alternatively, a further aspect of the invention provides a device for forming an anastomosis of two walls of a patient's digestive system, optionally a digestive tract. The device has an undeployed configuration for delivery to a target site for the anastomosis and a deployed configuration for implantation. The device is configured to apply a first compressive force to compress a first tissue section of the wall about a substantially closed loop shape to cause necrosis of the tissue in the first section, and to apply a second compressive force to a second tissue section of the wall laterally (e.g., radially) outwardly of the first section, the second compressive force being less than the first compressive force to optionally press the tissues together without causing necrosis.

[0040] Such a configuration allows for a compressive effect on the tissue walls that is tailored to assist in anastomosis formation. The compressive force can be concentrated in a first zone, leading to tissue necrosis where the anastomosis is formed. A smaller compressive force in a second zone laterally outside the first zone, optionally surrounding the first zone, presses the tissue walls together, encouraging tissue fusion as part of the healing effect, but optionally without necrosis in the second zone. This can result in a radially thick band of connective tissue around the anastomosis.

[0041] Such a structure can increase the area of ​​tissue junction with the goal of further ensuring a reliable continuous joint around the entire anastomosis. The process of tissue necrosis and healing whereby the anastomosis is formed is a biological process driven by compressive forces. Different patients may experience different rates of tissue necrosis, healing and tissue fusion, resulting in some variability in anastomosis formation from patient to patient. Also, while the biological process is expected to be uniform around the closed loop shape, in some cases variability may occur. For example, the joint may naturally be thicker in some areas than others. Such biological variability may be exacerbated by a patient condition such as diabetes. Providing a second area where the tissue walls are pressed together with less compressive force can mitigate such variability and assist the biological process of joining the tissues together with sufficient or enhanced radial thickness to create a robust, leak-free joint.

[0042] In some embodiments, the second structure comprises a third portion coupled to the first portion for distributing compressive forces from the first portion laterally outward with a reduced magnitude, and / or a fourth portion coupled to the second portion for distributing compressive forces from the second portion laterally outward with a reduced magnitude.

[0043] The third and / or fourth portions may comprise a semi-rigid and / or semi-flexible material, optionally a polymeric material. For example, the third and / or fourth portions may comprise struts, petals, or flanges extending laterally outward from the first or second portions, respectively.

[0044] The first and second parts may each carry at least one magnet for magnetically attracting the first and second parts to one another. The third and / or fourth parts need not and / or do not carry magnets. Other non-magnetic structures for generating the first compressive force may also be used, for example, a mechanically generated compressive force created by a stent, if used.

[0045] In any of the foregoing embodiments, the device or one or more components may be formed by any suitable technique, optionally including 3D printing techniques.

[0046] A further aspect of the present invention is a method of forming an anastomosis at a target site, optionally using a device as described above in any aspect, the method comprising: introducing an expandable stent into the target site; expanding a stent from an undeployed configuration to a deployed configuration to form a temporary stent anastomosis between tissue walls at a target site, the stent having a through channel for providing a functional anastomosis; and simultaneously with or without the expanding step, positioning first and second portions of the device against tissue of a wall surrounding the through channel, the first and second portions being magnetically attracted to one another to induce formation of a magnetic compression anastomosis around the through channel of the stent. Includes.

[0047] Non-limiting embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0048] [Figure 1] FIG. 2 is a side view of a stent having magnets, the stent being shown in its as-cut, unfolded form prior to thermoforming. [Diagram 2] FIG. 2 is a cross-sectional view of the stent in the configuration of FIG. 1. This configuration corresponds to the undeployed configuration, except that the undeployed configuration may be more radially compressed. The broader view of FIG. 2 is provided to make it easier to see the features of the device. [Diagram 3] FIG. 3 is a cross-sectional view of the stent of FIGS. 1 and 2 in a deployed configuration. [Figure 4] 1A-1C are cross-sectional views illustrating endoscopic insertion of a delivery device into a patient and to a target site for anastomosis of the digestive tract. [Diagram 5]5 is a cross-sectional view similar to FIG. 4 showing the next step of puncturing the tissue wall of the digestive tract at the target site. [Figure 6] 6 is a cross-sectional view similar to FIG. 5 showing the next step of retracting the delivery device towards the opening in the two tissue walls. [Figure 7] 7 shows an enlarged view of the distal end of the delivery device shown in FIG. 6. [Figure 8] 7 is a cross-sectional view similar to FIG. 6 showing the next step of partially deploying the stent with the magnet near the distal-most tissue wall opening. [Figure 9] 9 shows an enlarged view of the distal end of the delivery device and a partially deployed stent of FIG. 8. [Figure 10] 9 is a cross-sectional view similar to FIG. 8 showing the next step of further retracting the delivery device while deploying the stent with a magnet. [Figure 11] 11 shows an enlarged view of the distal end of the delivery device and stent of FIG. 10. [Figure 12] 11 is a cross-sectional view similar to FIG. 10 showing the next step of releasing the stent with magnets into a deployed configuration to apply magnetic compression to the tissue wall while simultaneously providing a temporary stent anastomosis with an operating through channel. [Figure 13] 13 shows an enlarged view of the stent of FIG. 12 in a deployed configuration. [Figure 14] 13 is a cross-sectional view similar to FIG. 12 showing the next step in which a permanent second compression anastomosis is formed around the stent anastomosis. [Figure 15] 15 shows an enlarged view of the formation of the compression anastomosis of FIG. 14. [Figure 16] 15 is a cross-sectional view similar to FIG. 14, showing the next step in which the stent anastomosis is replaced by a compression anastomosis. [Figure 17] 17 shows an enlarged view of the stent anastomosis replacement of FIG. 16. [Figure 18] FIG. 13 is a side view of a second example of a stent having magnets, the stent shown in an unfolded form while remaining cut in an undeployed configuration. [Figure 19]FIG. 19 is a side view of the stent of FIG. 18 shown in an as-cut, unfolded form in a deployed configuration. [Figure 20] FIG. 20 is an end view of the stent of FIGS. 18 and 19 in a deployed configuration. [Figure 21] 13A-13C are cross-sectional views of further examples of stents having magnets in a deployed configuration. [Figure 22] 13A-13C are cross-sectional views of further examples of stents having magnets in a deployed configuration. [Figure 23] 13A-13C are cross-sectional views of further examples of stents having magnets in a deployed configuration. [Figure 24] FIG. 13 is a top view of an alternative embodiment of a stent having magnets in a deployed configuration. [Diagram 25] 14 is a cross-sectional view similar to FIG. 13, showing an alternative attachment of the magnet to the stent. [Figure 26] FIG. 25 is an end view similar to FIG. 24, but showing an alternative stent configuration. [Figure 27] FIG. 13 is a profile view showing a stent changing from a generally circular deployed configuration to a generally streamlined post-deployed configuration. [Figure 28] FIG. 26 is a schematic perspective view from above of a further embodiment of a stent similar to that of FIG. 25. [Figure 29] FIG. 29 is a schematic side view of the stent of FIG. 28. [Diagram 30] FIG. 30 is a schematic top view of the stent of FIGS. 28 and 29. [Diagram 31] FIG. 31 is a schematic perspective view showing the stent of FIGS. 28 to 30 in a collapsed state. [Diagram 32] 13 is a schematic perspective view from above of a further embodiment of a stent assuming a curved post-deployment configuration. FIG. [Diagram 33] FIG. 33 is a schematic side view of the stent according to FIG. 32. [Diagram 34] FIG. 34 is a schematic top view of the stent of FIGS. 32 and 33. [Diagram 35] 13 is a schematic perspective view from above of a further embodiment of a stent in a post-deployment configuration, seen obliquely from the side; FIG. [Diagram 36]FIG. 36 is a schematic end view of the stent of FIG. 35. [Figure 37] FIG. 37 is a schematic side view of the stent of FIGS. 35 and 36. [Figure 38] 1 is a schematic perspective view of a further embodiment of a stent that assumes an elliptical disc shape in a deployed configuration. [Figure 39] FIG. 39 is a schematic side view of the stent of FIG. 38. [Diagram 40] FIG. 40 is a top view of the stent of FIGS. 38 and 39. [Diagram 41] 13 is a schematic perspective view from above of a further embodiment of a stent in a deployed configuration having radial extensions. FIG. [Diagram 42] FIG. 42 is a schematic side view of the stent of FIG. 41. [Diagram 43] FIG. 2 is a top perspective view of a stent for forming an anastomosis between the stomach and the intestine in a first comparative example. [Diagram 44] FIG. 11 is a cross-sectional view showing two magnetic members for forming an anastomosis in a second comparative example. [Diagram 45] FIG. 11 is a cross-sectional view showing two magnetic members for forming an anastomosis in a second comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0049] In the following description, the same reference numbers are used to indicate corresponding features, whether or not they are explicitly stated. Features from one embodiment can be used in combination with another, whether or not they are explicitly stated.

[0050] Before describing the present invention, reference is made to Figs. 43-45, which show two comparative examples, so that the advantages of the present invention can be appreciated. Fig. 43 shows a first comparative example in the form of an implantable expandable stent 150 to provide a stent anastomosis 152 between two body lumens, such as the stomach and the jejunum. The junction between the tissue walls is permanently dependent on the stent 150 for integrity, and therefore the durability of the anastomosis depends on the ability of the stent 150 to maintain a leak-free junction. Even with complex stent designs, durability may be limited. For example, over time, the stent 150 may be subject to the corrosive action of digestive fluids and constant movement between the body lumens. Leaks can easily occur if the stent becomes dislodged or broken, or if any part of the junction becomes incomplete. Leaks can be life-threatening to the patient.

[0051] 44 and 45 show a second comparative example of the form of a magnetic compression anastomosis formed by two rings 160 containing magnets 162. The two rings 160 are introduced separately, for example using two separate endoscopes (not shown), and positioned with the rings in contact with the tissue walls 164 and 166, such that the rings 160 are held by the mutual attraction of the magnets 162. The anastomosis is not formed immediately. Over time, for example 3-4 weeks, necrosis of the tissue clamped between the rings 160 causes the surrounding tissue to join and form a permanent tissue-tissue junction. The necrotic tissue and the attached rings 160 eventually loosen, leaving a permanent anastomosis. Compared to the first comparative example, such a compression anastomosis has the potential advantage of being permanently leak-free and not dependent on a permanent implant. However, unlike the first comparative example, the compression anastomosis is not instantaneous and requires sufficient time to form, which may vary from patient to patient. The medical practitioner does not know initially if the anastomosis is effective because this can only be observed later, and if it takes time for the anastomosis to form due to the rings loosening, it will require further investigative medical procedures. The absence of an instantly working anastomosis means that the patient's medical condition cannot be treated initially. If, for any reason, the rings and necrotic tissue do not loosen, the anastomosis cannot function properly. Also, the procedure for introducing and positioning the two rings 160 on either side of the two tissue walls 164 and 166 is more complicated in that two different endoscopes must be used, which are guided through different pathways to align with different body lumens.

[0052] 1-42 show an embodiment of a device 101 according to the invention. FIG. 1 shows a side view of an embodiment of an expandable stent 1 in an as-cut unfolded form before thermoforming. The stent 1 comprises a central tube region 8 and first and second portions 11 and 12 at either end carrying magnets 6 (61, 62, respectively). The stent is expandable from an undeployed configuration (FIG. 2) for introduction to a target site for anastomosis to a deployed configuration (FIG. 3) for implantation at a target site. In the undeployed configuration (FIG. 2), the stent 1 is radially compressed at the ends of the first portion 11 and the second portion 12. The stent has a transverse dimension (e.g., diameter) B1, for example in the range of 0.3 cm to 1.5 cm. In the deployed configuration (FIG. 3), the central tube region 8 radially expands to a transverse dimension larger than B1, and the first portion 11 and the second portion 12 bend outwardly towards each other to define a clamping element around the central tube region 8. The first and second portions 11, 12 may bend or articulate from opposite ends of the central tube region 8 such that the first and second portions 11, 12 (and magnets 6) move laterally outward and / or axially (longitudinal of axis A) toward one another. The central tube region 8 provides a through channel from one end of the device to the other, having a lateral dimension (e.g., diameter) W1. For example, dimension W1 may range from about 1.5 cm to 6 cm.

[0053] The stent 1 may be self-expanding, made from or including a shape memory material, such as Nitinol. Such a stent 1 must be held in a non-deployed configuration, for example, by a restraining sheath, and gradually self-expands from one end as the sheath is slid off the stent and / or as the stent is pushed out of the restraining sheath. For example, one of the first and second portions 11, 12 may self-expand first, followed by the central tube region 8, and finally the other of the first and second portions 11, 12. The stent 1 may have a frame structure to facilitate expansion. Some embodiments of the stent 1 may be monolithic, for example laser cut from tubular stock. Alternatively, the stent 1 may be of mesh or braided structure.

[0054] The magnets 6 are arranged and / or oriented such that the first portion 11 and the second portion 12 magnetically attract each other. When the distance between the first portion 11 and the second portion 12 is reduced, the attraction force is particularly strong in the deployed configuration (FIG. 3). Optionally, the magnets 6 in each portion 11, 12 may be arranged and / or oriented such that they repel each other, thus giving each portion 11, 12 an additional tendency to expand laterally and / or circumferentially from the undeployed configuration. The magnets 6 are arranged in an annular arrangement. In this embodiment, each magnet is attached to an apex of a polygonal structure. The discrete nature of the magnets leaves spaces between adjacent magnets in the circumferential direction, especially in the deployed configuration. In the illustrated form, the magnets 6 are arranged in a single row, with each magnet in the first portion 11 generally aligned with a respective magnet in the section portion 12. Magnets 6 arranged offset from each other and / or several rows of magnets 6 in each portion 11, 12 are also conceivable.

[0055] At least one, preferably both, of the first and second portions 11, 12, optionally collectively with the magnet 6, further comprises a pressure element 7 (best seen in FIG. 1) having or assuming a closed loop shape. The pressure element 7 may be a single element or may comprise multiple segments directly or indirectly coupled to each other. The pressure element 7 (optionally in combination with the magnet 6) serves to provide a substantially circumferentially continuous surface for applying pressure uniformly to the wall tissue around the closed loop, even though the individual magnets are circumferentially spaced or discontinuous in the deployed configuration. The pressure element 7 may be provided by a flexible filament, for example a polymer filament. As shown in FIG. 1, the flexibility avoids the pressure element 7 from impeding the compression of the stent 1 to the undeployed configuration. The pressure element 7 may be tensioned when in the deployed configuration.

[0056] The magnets 6 (61, 62) may be approximately flush with the portion of the stent 1 that carries them (as shown diagrammatically in FIG. 13), or the magnets 6 may be closer to the tissue than the portion of the stent 1 that is in the deployed configuration (as shown diagrammatically in FIG. 3), or the magnets 6 may be farther from the tissue than the portion of the stent 1 that is in the deployed configuration (as shown diagrammatically in FIG. 25). In the latter case, the magnets may tend to compress the respective portion of the stent against the tissue such that the stent struts that contact the tissue can also act as pressure elements to distribute a compressive force around the closed loop shape.

[0057] The device 101 and / or the stent 1 may further comprise a flexible cover (not shown) covering at least partially the surface of the first region 11 and / or at least partially the surface of the central tube region 8 and / or at least partially the surface of the second region 12. The cover may optionally be generally impermeable to materials passing through the body lumen for anastomosis. The cover may be an internal and / or an external cover. The cover may be or include, for example, a woven or nonwoven synthetic fabric. The cover may function to help seal the stent against the tissue wall and / or against the through channel to reduce the risk of leakage when the stent is deployed. Additionally or alternatively, the cover may help provide an atraumatic exterior of the device, especially when in the deployed configuration.

[0058] Figures 4-17 illustrate a procedure for implanting the device 101 of Figures 1-3 using an endoluminal and / or endoscopic instrument 10. Figure 4 illustrates the introduction of the instrument 10 into the patient's digestive tract to a target site for anastomosis. For example, the target site may be between the wall of the stomach and the wall of the jejunum to create a gastrojejunal anastomosis that bypasses the duodenum and optionally a portion of the jejunum. An example of an alternative target site is between the wall of the ileum and the wall of the jejunum to create an ileo-jejunal anastomosis.

[0059] The intraluminal and / or endoscopic instrument 10 is insertable through the patient's esophagus. The instrument 10 comprises a cutting and / or piercing element 12 that enables it to pierce the tissue walls 4 (41, 42, respectively) of the digestive tract, in particular the stomach and intestines. The piercing and / or cutting element 12 is preferably located on or advanceable to a distal region of the instrument 10 that enables the instrument 10 to penetrate the tissue walls 41, 42 (FIG. 5).

[0060] 6 and 7 show retraction of the piercing and / or cutting element 12, and optionally partial retraction of the instrument 10, so that the distal end is positioned near the opening formed in the tissue wall 4. The intraluminal and / or endoscopic instrument 10 optionally includes one or more elements for bringing the two tissue walls 41, 42 into apposition. A partially deployed stent (shown in the next step) can also be used as an element for bringing the tissue walls 41, 42 into apposition.

[0061] 8 and 9 show the first step of deployment of the device / stent 1 to establish an anastomosis. In the first step, the stent 1 is partially deployed by uncovering one of the first and second portions, e.g., the first portion 11, allowing the respective portion to self-expand. The stent 1 may be uncovered by progressively retracting the restraining sheath or by progressively advancing the stent 1 through the open end of the sheath. The first portion 11 begins to deploy by bending or moving toward its laterally extended position of the deployed configuration.

[0062] Figures 10 and 11 show the next step of uncovering the central tube region 8. As shown in Figure 11, the central tube region 8 may remain compressed until the stent is generally unconstrained. The increased maximum lateral profile of the stent 1 prevents it from backing out through the opening in the tissue walls 41, 42.

[0063] 12 and 13 show the complete uncovering of the stent 1, releasing the second portion 12 and allowing the stent 1 to self-expand to its deployed configuration. The magnetic attraction between the magnets of the first portion 11 and the magnets of the second portion 12 clamps the tissue walls 41, 42 tightly together. The first and second portions 11, 12 also function to fix the stent 1 in its position bridging the opening in the tissue walls 41, 42. The central tubular portion 8 expands to its full width W1 and provides a through-channel 5 from one side of the tissue wall to the other. Thus, the stent 1 provides a stent anastomosis 201 with a functional through-channel 5 immediately after implantation of the device. The lateral force exerted by the central tubular portion 8 on the edges of the tissue wall, optionally assisted by a flexible cover (described above), provides a seal to prevent leakage of gastric and / or intestinal contents from the stent anastomosis 201.

[0064] Thus, the functional through-channel 5 can enable the stent anastomosis to function and provide treatment or therapy for a patient's condition immediately after implantation. A medical practitioner can observe the function and positioning of the stent anastomosis to confirm correct placement. Once the stent 1 is deployed, the device 10 can be withdrawn and optionally removed from the body.

[0065] 14 and 15, magnetic attraction between the first and second portions 11, 12 disposed about the through channel induces the formation of a magnetic compression anastomosis. The magnetic attraction exerts pressure on the tissue walls 41, 42, limiting blood perfusion in the clamped areas of the tissue walls. Over time, typically about 3-4 weeks, the clamped tissue becomes necrotic (shown at 17), inducing the surrounding tissue to heal as a permanent tissue-tissue junction where the necrotic tissue naturally separates or breaks down.

[0066] 16 and 17, the stent 1 and / or device 101 are attached only to the necrotic tissue 17. Due to the separation of the necrotic tissue 17, the stent 1 moves away from the tissue walls 41, 42, leaving behind a permanent compressed anastomosis 202 having a width W2 slightly wider than the width W1 of the channel of the stent anastomosis 201. For example, the width W2 of the permanent anastomosis may be about 2 cm to about 6 cm. The device 101, still attached to the necrotic tissue, can pass through the digestive tract and be expelled from the body.

[0067] Thus, device 101 allows for the formation of a temporary stent anastomosis 201 that allows for immediate function, and then a permanent compression anastomosis 202 that biologically replaces stent anastomosis 201. Device 101 can be implanted using a single minimally invasive surgical procedure, typically an endoscopic procedure, but optionally a laparoscopic procedure can also be used.

[0068] Optionally, the stent 1 may include break points and / or bioabsorbable material, whereby the dimensions may be reduced by the stent 1 separating into separate segments (not shown in FIG. 17). One implementation of the stent 1 includes bioabsorbable connectors or hinges that divide the stent 1 into segments so that the stent 1 may be more easily expelled. An alternative embodiment of the stent 1 that includes break points may be considered to break when the magnets 6 are in close contact after the permanent anastomosis 202 is successfully formed. Further embodiments may be shape-transformed to a post-implantation configuration (FIG. 27). For example, one or more structural support portions of the stent may weaken and optionally break, allowing a force applied by another part of the device to deform the stent to its post-implantation position. For example, the force may come from the stent itself or from an elastic cover. In the post-deployment configuration, the shape of the device may be more streamlined, e.g., slightly elongated, than the deployed configuration to facilitate passage through the intestine and anus. For example, FIG. 27 shows a stent 1 being transformed from a generally circular deployed configuration to a generally elongated (eg, oval, or elliptical or diamond shaped) post-deployment configuration or profile 21.

[0069] FIG. 18 shows a side view of a modified embodiment of a stent 1 with magnets 6 in the undeployed configuration 2 of the device 101. The stent 1 comprises a monolithic frame structure defining a central tubular portion 8 with a forming structure 22. The forming structure 22 comprises a polygon mesh that is materially connected at every intersection of the stabilizing elements 13. However, stabilizing elements 13 that are movable relative to each other are also conceivable. The magnets 6 are connected to the stent 1 at the distal region 11 and at the proximal region 12 of the stent 1. The magnets 6 are connected via connecting elements 7. The magnets 6 are arranged on the stent 1 in the undeployed configuration 2 in several rows offset in the longitudinal direction of the stent 1. The rows of magnets 6 are connected in a zigzag pattern of connecting elements 7 on the distal region 11 and at the proximal region 12. Several rows of magnets 6 allow to reduce the attraction of adjacent magnets 6 due to the increased distance. The stent 1 can also include an impermeable structure (not shown in FIG. 18). The lateral profile width B1 of the stent 1 in the undeployed configuration 2 is less than the lateral width of the catheter (not shown in FIG. 18) of the device 101.

[0070] Figure 19 shows an embodiment of a stent 1 with magnets 6 according to Figure 18 in a deployed configuration 3. In the deployed configuration 3, the magnets 6 arranged in separate rows in the non-deployed configuration are arranged on a closed loop equidistantly spaced from each other by connecting elements 7. The stent 1 assumes its deployed configuration 3 (not shown in Figure 19) by generating a radial force that increases its lateral profile and expands the temporary channel without the action of an external force on the stent 1. The lateral profile width B2 of the stent 1 in the deployed configuration 3 is greater than the width of the catheter (not shown in Figure 18) of the device 101. The lateral profile width B2 is also greater than the incision opening in the tissue wall due to the insertion of the device 101.

[0071] FIG. 20 shows a top view of the stent 1 with the magnet 6 in the deployed configuration 3 according to FIG. 19. The connecting element 7 and the magnet 6 form a closed loop 18 with a polygonal structure arranged laterally outside the temporary channel 5. The closed loop 18 in the distal and proximal regions of the stent 1 can apply pressure between the first and second parts of the device 101 (not shown in FIG. 24). The shape of the closed loop 18 corresponds to a permanent compression anastomosis. The magnet is arranged at the maximum lateral distance of the stent 1. The forming structure 22 of the stent 1 applies pressure laterally outward and contributes to the fixation of the stent 1.

[0072] Figure 21 shows an embodiment of a stent 1 with a magnet 6 according to figure 3. For reference numbers referring to the aforementioned features, please refer to figure 3. The stent 1 of figure 21 is provided with a protective cover 19 that makes the stent 1 atraumatic. The device 101 can also be partially or completely covered with a smooth cover so that the stent can be guided atraumatically along the digestive tract and does not get stuck. The dashed oval indicates diagrammatically the temporary channel 5.

[0073] 22 shows a cross-sectional view of one embodiment of a stent 1 with a magnet 6 in a cross-sectional view forming a temporary channel 5 in a deployed configuration 3. The curved structure of the stent 1 in the embodiment of FIG. 22 prevents the stent 1 from getting stuck or catching as it disengages from the fused tissue wall. The majority of the forming structure 22 of the stent 1 in the deployed configuration 3 is located in a distal region of the stent 1. The dashed oval indicates the diameter of the temporary channel 5 generally.

[0074] FIG. 23 shows a stent 1 according to FIG. 22 provided with a single protective cover 19 which, in contrast to FIG. 21, only needs to be attached to its distal side to make the stent 1 atraumatic.

[0075] Figure 24 shows a top view of an alternative embodiment of a stent 1 with magnets 6 of a device 101 to that of Figure 20. For reference numbers relating to the same subject matter, see Figure 20. The lateral profile comprising the magnets 6 and the connecting elements 7 and constituting the closed loop 18 has a circular shape as opposed to a polygonal shape.

[0076] Figure 26 shows a further embodiment, similar to Figure 24, but with stent 1 having a non-circular shape, such as a generally oval or elliptical shape, having a longer transverse dimension B2. Such a stent may be useful for directing the non-circular shape of the anastomosis. Also, the non-circular shape may be more streamlined than a circle, making it easier to eject stent 1 from the body after the stent anastomosis separates from the tissue wall.

[0077] 28-31 show a further embodiment similar to that shown in Figs. 1-17 and 25. The stent 1 carries a proximal magnet 61 and a distal magnet 62 connected to other proximal magnets 61 and distal magnets 62, respectively, by a connecting element 7, thereby forming a proximal closed loop 181 and a distal closed loop 182 for applying pressure to the intervening tissue wall due to magnetic attraction. The forming structure 22 of the stent 1 in the deployed configuration 3 is bent laterally outward at the proximal and distal sides of the stent. The laterally outwardly bent forming structure 22 forms a tubular wall 8 and forms a through channel 5. As can be seen in Fig. 29, the intermediate space between the proximal closed loop 181 and the distal closed loop 182 of the stent 1 is connected only by the tubular wall 8. The proximal closed loop 181 and the distal closed loop 182 in the deployed configuration 3 of the stent are separated and / or held apart by the tissue wall when the stent is transformed into the deployed configuration. The posts of the connecting structure can, for example, define a generally symmetric teardrop or keyhole configuration in radial profile (eg, FIG. 29).

[0078] Referring to FIG. 30, in the deployed state, the closed loops 18 are essentially polygonal in shape. The connecting elements 7 are, in this example, S-shaped to facilitate good articulation when the stent collapses to the undeployed configuration and when the stent expands from the undeployed configuration to the deployed configuration. As seen in FIG. 30, within each closed loop 18, the magnets 6 are supported in an alternating circumferential direction by the forming structure and the connecting elements 7. That is, alternating magnets 6 are supported in an intervening position only by the connecting elements 7. As the stent moves between the deployed configuration (FIG. 30) and the undeployed configuration (FIG. 31), the intervening magnets 6 supported only by the connecting struts 7 move both axially and radially relative to the other magnets supported directly by the forming structure. In the undeployed configuration, the connecting struts 7 and magnets 6 are arranged in multiple circumferential rows spaced axially from one another by approximately the length of the connecting elements 7. Such an arrangement allows the stent to be collapsed to a small diameter for introduction to the target site of the anastomosis, yet still carry a relatively large number of magnets at each end for optimal magnetic compression effect.

[0079] While the stents in Figs. 28-31 may have a generally uniform or uniformly repeated shape in the circumferential direction, Figs. 32-43 show further embodiments in which the stent has a more circumferentially segmented structure. In particular, the stent 1 is divided into first and second segments separated by one or more structural discontinuities or gaps 23. In the illustrated form, the gaps 23 are defined in the inner part of the connecting structure, and the first and second segments are only connected at the outer circumference of each end and / or clamp portion of the stent 1. The gaps 23 provide the first and second segments with a greater freedom of movement and / or conformity compared to a uniform structure. The first and second segments are only connected on the outside of the tubular section 8 via a reduced number of struts. The gaps 23 may allow the stent 1 to more easily assume a deformed or compressed form after implantation, optionally under external influences, for example when passing through the intestine or anus, and / or optionally under the influence of the device itself. Such effects may result, for example, from magnetic attraction between the magnets 6, and / or the stent tending to reshape itself into its post-implantation configuration, and / or an elastic covering of the stent (not shown) exerting forces tending to deform the stent.

[0080] 32-34, regardless of the segmented design of the structure, the stent 1 may have a configuration similar to that of FIG. 22 described above. The stent 1 forms a generally flat transverse profile that forms a proximal closed loop 181 and a distal closed loop 182 together with the proximal magnet 61 and the distal magnet 62. For example, the stent 1 may have a generally asymmetric teardrop shape in the radial profile (e.g., FIG. 33). The asymmetric shape may be particularly suitable for certain anastomosis locations in the body lumen. The asymmetric shape may also provide advantages with respect to ease of evacuation in the body lumen after the stent anastomosis separates from the tissue wall.

[0081] Referring to FIG. 34, in addition to or instead of an asymmetric shape in the radial profile, the stent 1 may also have an elongated or elliptical profile, similar to the profiles discussed above with respect to FIG. 29, or other non-circular profiles. Such a stent may be useful for inducing a non-circular shape of the anastomosis. Also, a non-circular shape may be more streamlined than a circular shape, making it easier to eject the stent 1 from the body after the stent-anastomosis separates from the tissue wall. The forming structure 22 of the stent 1 includes stabilizing elements 13 of different lengths such that the stent 1 assumes an elliptical profile. However, the through channel 5 formed by the tubular wall 8 section of the forming structure 22 may have a generally circular transverse profile as shown, or may have a non-circular shape as desired.

[0082] 35-40 show examples of post-deployment configurations that differ from the deployed configuration. The stent may be preformed in the post-deployment configuration, or as described above, the post-deployment configuration may optionally be subject to external influences, for example when passing through the intestine or anus, and / or optionally subject to magnetic attraction between the magnets 6, and / or the result of an elastic covering (not shown) of the stent exerting forces that tend to deform the stent.

[0083] In the example of Figs. 35-37, in the deployed configuration, the closed loops (181 and 182) form a curved lateral profile arc by being bent at an angle. The stent 1 is configured to assume a curved disk shape due to the shape memory alloy and / or due to the distance between the proximal magnet 61 and the distal magnet 62 being reduced. The smaller the distance, the stronger the magnetic force. In addition, in this embodiment, the structural gaps 23 are located laterally on both sides of the stent 1, thereby maintaining the tubular wall 8 for the through channel 5 while the bending is supported by the forming structure 22. The structural gaps 23 preferably allow for a variable lateral width of the through channel 5. It can be considered that when the stent 1 assumes the deployed configuration 3, the width of the gaps 23 increases, thereby increasing the lateral profile of the through channel 5 formed by the tubular wall 8 section of the forming structure 22. The tissue walls surrounded by the stent 1 preferably prevent the stent 1 from assuming the deployed configuration while the compression anastomosis is not yet completed. Once the stent has separated from the tissue wall after completion of the magnetic compression anastomosis, it may assume a post-deployment configuration.

[0084] 36, the proximal closed loop 181 and the distal closed loop 182 are bent at an angle in the deployed configuration, preferably by bending two equal-sized halves in the same longitudinal direction around a bending axis to form an arc with the transverse profile of the stent. The majority of the stent 1 is located on one longitudinal side, proximal or distal, of the closed loops (181, 182). In this embodiment, the through channel 6 formed by the tubular wall 8 of the forming structure 22 is located entirely on one side of the stent 1 from the closed loops (181, 182) of the stent. This arrangement and / or the arrangement of the structural gap 23 allows the stent 1 to collapse without structural constraints on the deployed configuration of the forming structure 22.

[0085] The example of Figures 38-40 may be a further continuation of the bending deformation of Figures 35-37 to the final post-deployment configuration or may be independent from Figures 35-37. With reference to Figures 38-40, the post-deployment configuration 24 is preferably assumed after the compression anastomosis of the tissue walls is completed. The magnetic and / or structural forces leading to the post-deployment configuration 24 are preferably strong enough to peel off the necrotic tissue in the closed loop once the compression anastomosis is completed. In a preferred embodiment of the stent 1, the stent forming structure 22 may be brittle and / or weak and / or flexible. Most of the forces acting on the stent are induced by the magnet 6. The magnet 6 is configured to exert a desired amount of force, while the forming structure 22 only directs the magnetic force to transform the stent 1 from the post-deployment configuration 24. The lateral profile of the stent 1 is significantly reduced due to the stent 1 folding outward around the folding axis. Once the compression anastomosis is established, the stent 1 assumes a fully curved lateral profile, or at least a lateral profile that is preferably fully curved at an angle of at least 45°. The stent 1 may be self-convertible to the post-deployment configuration. The stent 1 may be folded in approximately mirror symmetry so that the folded lateral profiles are aligned and / or the magnets 6 can form the magnet stack 25. However, asymmetric folding arrangements can be envisioned to reduce the dimensions of the stent 1. In this embodiment, the distal recessed magnets and the proximal recessed magnets 63 essentially remain in the previous lateral plane of the stent 1. The other magnets 6 form the magnet stack 25 in the order of the previous proximal magnets, distal magnets, distal magnets, and proximal magnets. By adopting a curved lateral profile, the stent 1 is more streamlined and also has a smaller lateral width in at least one dimension. The post-deployment configuration 24 allows for a more streamlined profile of the stent 1 so that the stent can more easily pass through the gastrointestinal tract. The former tubular wall 8 is divided into two sections aligned along the longitudinal direction of the stent.

[0086] Referring to FIG. 39, the forming structure 22 and the connecting element 7 are generally positioned away from the previous side of the stent 1. The magnet stack 25 consists of a distal magnet 62 and a proximal magnet 61, which are aligned approximately perpendicular to the previous lateral profile of the stent and / or approximately along the folding axis of the stent 1. In a preferred embodiment, the lateral profile of the stent 1 in the deployed configuration 24 generally increases along the folding axis, particularly starting from the recessed magnet 63, to a maximum lateral profile at the location of the stent 1, preferably at the center of the stent 1. From that location, the lateral profile of the stent decreases, preferably mirror-symmetrically along the folding axis. The stent 1 can also be considered to assume a directional, non-mirrored profile in the deployed configuration 24 to further aid in passing through the gastrointestinal tract.

[0087] 40, it can be seen that the previous maximum lateral width is reduced by half in the post-deployment configuration 24 of the stent 1. The stent 1 in the post-deployment configuration 24 is elongated such that the stent 1 does not easily become lodged in the gastrointestinal tract and may be more easily expelled through the patient's anus.

[0088] 41 and 42 show a further embodiment of a device or stent 1 in a deployed configuration 3. The stent 1 is configured to apply a first compressive force to compress a first tissue section 84 of the wall about a substantially closed loop shape to cause necrosis of the tissue in the first section, and apply a second compressive force to a second tissue section 86 of the wall laterally (e.g., radially) outwardly of the first section, the second compressive force being less than the first compressive force, optionally to press the tissue together without causing necrosis.

[0089] The stent 1 or the entire device comprises a first structure including first and second portions 7 for compressing a first tissue section 84 of the wall about a substantially closed loop shape between the first and second portions to cause necrosis of the tissue in the first section, and a second structure 26 disposed laterally (e.g. radially) outside the first and / or second portions 7 of the first structure for compressing tissue in a second tissue section 86 laterally outside the first tissue section 84 with a smaller compressive force than the first structure, the second structure optionally configured to press the tissue together without causing necrosis. The first structure may optionally be or include a stent structure, optionally with a magnet, according to any of the previous embodiments.

[0090] The second structure comprises a radial extension 26 formed by a secondary connecting element 71. The secondary connecting element 71 may form part of the stent 1 and / or may be provided by a structure coupled to the stent and / or the magnet. Such additional structures may be made from a different material than the stent, for example a polymeric material.

[0091] 41 and 42 show the proximal section of the stent forming a proximal closed loop 181, located adjacent to the tissue wall. The secondary connection elements 71 of the stent 1 extend radially outward in an arc to form an essentially star-shaped profile. However, other star-shaped and / or non-star-shaped profiles are envisaged that increase the contact area of ​​the stent 1 with the tissue wall 41, 42 in the radial direction. In particular, semicircular elliptical and polygonal shapes are also envisaged. A substantially continuous band of material may also be used. The distal section of the radial extension 26 formed by the secondary connection elements 71 may also be connected (not shown in Figs. 41 and 42) so that the contact area is further maximized. Thus, the portion of the stent 1 between the magnets 6 may be adjusted so that the compressive pressure is distributed along the closed loop 181 with less compressive force. The secondary connection elements 71 may also apply compressive force over a larger area by means of a hinge, shape memory alloy and / or spring element structure. The forces resulting from the magnetic attraction of the magnetic elements and / or contact with the tissue wall, in addition to the higher compressive forces along the annular line, can be extended with reduced force over a larger surface area via the radial extensions 26 along the annular bands between the closed loops (181, 182). As shown in FIG. 42, the magnetic elements 6 are connected to the rigid connecting elements 7 such that the through channels 5 can form a stented temporary anastomosis.

[0092] The above-described arrangement of radial extensions 26 enables one embodiment of stent 1 to apply a tailored compressive force to tissue walls 41, 42, which is concentrated in a first region, e.g., radially inner annular region 84, and is less in a second region surrounding the first region, e.g., radially outer annular region 86. If desired, additional or auxiliary magnets (not shown) can also be carried by extensions 26, but provide a weaker compressive force than magnets 26. For example, the additional or auxiliary magnets may be smaller than magnets 26.

[0093] Additionally, the above-described arrangement of radial extensions 26 serves to further increase fixation of stent 1. If desired, extensions 26 may be sufficiently rigid to constrain and maintain stent 1 at the anastomosis even after necrotic tissue has separated from tissue walls 41 and 42. Alternatively, extensions 26 may be sufficiently flexible so as not to prevent substantial separation of stent 1 from tissue walls 41 and 42 after formation of the anastomosis.

[0094] In the illustrated embodiment, the magnet is carried by and / or permanently attached to the expandable stent. This allows the entire device to be introduced in a single step, approaching the target site via a single path through the body, without the need to access both sides of the target site independently using two different devices via two different access paths. However, a stent 1 without a magnet 6 attached is also conceivable. The magnet 6 can be assembled to the stent 1 before introduction into the body. Alternatively, separate magnetic elements, e.g. magnetic rings, can be implanted in alignment with each other on the respective tissue walls before or after stent implantation, the magnetic elements functionally cooperating with the stent as a combined device.

[0095] The above description is merely illustrative of non-limiting examples useful for understanding the present invention. Many modifications and equivalents can be used without departing from the principles of the present invention. Although certain features and ideas have been emphasized above and in the appended claims, protection is claimed for any novel features and / or ideas described herein and / or shown in the drawings, regardless of whether or not emphasis is given.

Claims

1. 1. A device (101) for forming an anastomosis (201, 202) between two walls (4) of a patient's digestive system, optionally a digestive tract, said device having an undeployed configuration (2) for delivery to a target site for said anastomosis and a deployed configuration (3) for implantation, said device comprising a stent (1) expandable from said undeployed configuration (2) to said deployed configuration to form a stent anastomosis (201), said stent (1) including a through channel (5), and in said deployed configuration (3) of the device first and second portions (11, 12) of the device are positioned laterally outside said through channel (5) in an annular arrangement, said first and second portions magnetically attract each other to form a compression anastomosis (202) around said through channel (5) of said stent (1).

2. The device of claim 1 , wherein the stent (1) self-expands from the undeployed configuration (2) to the deployed configuration (3).

3. 10. The device of claim 1, wherein in addition to axial and / or lateral dimensional changes, the stent (1) changes shape when expanded from the undeployed configuration (2) to the deployed configuration (3).

4. 2. The device of claim 1, wherein at least one, and optionally both, of the first and second parts (11, 12) are configured to move by swinging and / or articulating and / or bending laterally outward when the device expands from the undeployed configuration (2) to the deployed configuration (3).

5. 2. The device of claim 1, wherein at least one, and optionally both, of the first and second portions (11, 12) are configured to move from positions adjacent their respective axial ends of the stent (1) to spaced-apart positions between the axial ends when the device expands from the undeployed configuration (2) to the deployed configuration (3).

6. 2. The device of claim 1, wherein at least one, and optionally both, of the first and second portions (11, 12) are configured to approach the other of the first and second portions when the device expands from the undeployed configuration (2) to the deployed configuration (3).

7. 2. The device of claim 1, wherein the through channel (5) of the stent (1) is defined by a tubular wall (8) of the stent (1) and / or the size of the through channel (5) of the stent (1) expands laterally when the device moves from the undeployed configuration (2) to the deployed configuration (3).

8. 2. The device according to claim 1, wherein at least one, and optionally both, of the first and second parts (11, 12) comprises a plurality of magnets (6).

9. 9. The device of claim 8, wherein the magnets are arranged to enable the portions to transform between the undeployed configuration and the deployed configuration of the device, and the magnets (6) are arranged in an annular arrangement at least in the deployed configuration (3).

10. 9. The device of claim 8, wherein at least a portion, and optionally all, of the magnets (6) are fixedly attached to and / or have a substantially fixed relationship to the stent (1) in the undeployed configuration (2) and the deployed configuration (3) of the device.

11. 9. The device according to claim 8, wherein at least one, and optionally both, of the first and second parts (11, 12) comprise a closed-loop shaped pressure element (7) for compressing tissue in the wall and inducing tissue necrosis when the first and second parts (11, 12) are magnetically attracted to each other.

12. 12. The device according to claim 11, wherein the pressure element (7) comprises a flexible filament, such as a polymer filament.

13. 12. Apparatus according to claim 11, wherein the pressure element comprises a frame element (7) of the respective part (11, 12).

14. 9. The device of claim 8, wherein the magnets (6) are connected by frame elements (7) configured to collapse circumferentially about the stent (1) when the device is in the undeployed configuration (2).

15. 9. The device according to claim 8, wherein at least one, and optionally both, of the first and second parts are configured to arrange the magnets (6) in a plurality of longitudinally offset circumferential rows in the respective parts when in the undeployed configuration, and in substantially a single circumferential row in the deployed configuration.

16. 16. The device of claim 15, wherein each of the portions comprises a connecting element (7) connecting the magnets (6), and the rows of magnets are connected in a zigzag pattern by the connecting elements (7) when in the undeployed configuration.

17. 9. The device according to claim 8, wherein at least one of said first and second parts, optionally both, comprises a forming structure including radial elements and a circumferential loop structure with connecting elements (7) connecting between the radial elements of said forming structure, said magnets (6) being supported alternately in said circumferential direction by said forming structure and said connecting elements (7).

18. The device of claim 8 , wherein the magnets on the first and second portions are substantially aligned with the other portions, at least in the deployed configuration.

19. The apparatus of claim 8 , wherein at least some of the magnets carried on the same part are configured to repel each other.

20. 2. The device of claim 1, wherein in the deployed configuration, at least one, and optionally both, of the first and second portions have a contour that includes a convexly curved portion about the through channel, resulting in a concavely curved portion radially outward of the convexly curved portion.

21. 21. The device of claim 20, wherein the concavely curved portion merges into a substantially flat perimeter portion.

22. 2. The device of claim 1, wherein the device is configured to change configuration to a post-deployed configuration during a post-implantation period, the post-deployed configuration having a more streamlined shape than the deployed configuration (3) for passage or removal through a body orifice, e.g., a natural body orifice.

23. 23. The device of claim 22, wherein at least one region of the stent (1) is configured to weaken and / or break down over a period of time after implantation, allowing the device to transform from the deployed configuration (3) to the post-deployed configuration (24).

24. 23. The device of claim 22, wherein the stent includes one or more structural discontinuities and / or structural gaps that define areas of relative weakness to allow the stent to deform, e.g., by bending and / or folding, into the deployed configuration (24).

25. 2. The device of claim 1, wherein the stent (1) comprises or is made of one or more of the following: a shape memory material, a shape memory alloy, an alloy containing nickel and titanium, nitinol, stainless steel, tungsten, a bioabsorbable material.

26. 2. The device of claim 1, wherein the stent (1) has one or more of the following: a self-expanding structure, a monolithic structure, a self-supporting structure, a polygonal structure, a frame structure, a wire mesh structure, one or more connectors between regions of the stent (1), optionally at least one connector made from a bioabsorbable material.

27. 2. The device of claim 1, comprising an atraumatic covering of a flexible material at least partially covering (i) the stent (1) and / or (ii) the first portion and / or (iii) the second portion.

28. A device (101) for forming an anastomosis (201, 202) between two walls of a patient's digestive system, optionally the digestive tract, said device optionally according to any of the preceding claims, said device having an undeployed configuration (2) for delivery to a target site for said anastomosis and a deployed configuration (3) for implantation, said device comprising: a first structure (8, 11, 12) including first and second portions for compressing a first tissue section of the wall about a substantially closed loop shape between the first and second portions to cause necrosis of tissue within the first section; a second structure (26) disposed laterally (e.g., radially) outward of the first and / or second portions of the first structure for compressing tissue in a second tissue section laterally outward of the first tissue section with a compressive force less than that of the first structure, the second structure being optionally configured to press tissue together without causing necrosis; An apparatus (101).

29. 29. The apparatus of claim 28, wherein the second structure (26) comprises a third portion (71) coupled to the first portion for distributing compressive forces from the first portion laterally outward with a reduced magnitude, and / or a fourth portion (71) coupled to the second portion for distributing compressive forces from the second portion laterally outward with a reduced magnitude.

30. 30. The device according to claim 29, wherein the third portion (71) and / or the fourth portion (71) comprise a semi-rigid and / or semi-flexible material, optionally a polymeric material.

31. 30. The apparatus of claim 29, wherein the first and second parts each carry at least one magnet (61, 62) for magnetically attracting the first and second parts to each other, and the third and / or fourth parts do not carry a magnet.

32. A method for creating an anastomosis (202) of two sections of the digestive system, optionally the digestive tract, of a patient, said method optionally using a device according to any of claims 1 to 31, Inserting said device (101) into a patient, optionally via the esophagus into the digestive system; - puncturing and / or cutting a first tissue wall portion (41) and a second tissue wall portion (42) forming two openings at a target site for said anastomosis; Optionally, bringing the two intestinal tissue wall (4) portions into close contact; Introducing an expandable stent (1) into the target site; expanding the stent (1) from an undeployed configuration (2) to a deployed configuration (3) to form a temporary stent anastomosis (201) between the walls, the stent (1) having a through channel (5) for providing a functional anastomosis; Simultaneously or asynchronously with the expanding step, positioning first and second portions of the device against tissue of the wall around the through channel (5), the first and second portions magnetically attracting each other to induce a magnetic compression anastomosis (202). A method comprising:

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