Removable stent

Abstract

An illustrative endoluminal implant having an elongate tubular member. The elongate tubular member has a proximal stent, a distal stent, and interconnected cannulas. The proximal stent tapers from a first outer diameter adjacent the proximal region to a second, smaller outer diameter adjacent the distal region. The outer diameter of the distal stent is smaller than the first outer diameter of the proximal stent. The interconnected cannulas are collapsible under the effect of the applied radial force such that the cannulas can be positioned through the native valve or sphincter.

Description

This case is a divisional application of invention patent application number 201980051829.5 Cross-references to related literature

[0001] This application claims priority under 35 U.S.C. §119 to U.S. Provisional Patent Application No. 62 / 680,175, filed on June 4, 2018, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0002] The present invention generally relates to methods and devices for various digestive system diseases. More specifically, the present disclosure relates to a removable stent for extending through a valve region. Background Art

[0003] Implantable stents are devices placed in tubular body structures, such as blood vessels, esophagus, trachea, bile duct, colon, intestines, stomach, or body cavities, to provide support and hold the structure open. These devices are manufactured by any of a variety of different manufacturing methods and can be used according to any of a variety of methods. Among the known medical devices, delivery systems and methods, each has certain advantages and disadvantages. There is a continuing need to provide alternative medical devices and delivery / retrieval devices, as well as alternative methods of manufacturing and using medical devices and delivery / retrieval devices. Summary of the invention

[0004] The present invention is directed to several alternative designs, materials, methods of making medical device structures and related uses thereof, such as stents for preventing leakage after anastomotic surgery and / or treating various gastrointestinal, digestive or other diseases.

[0005] An exemplary embodiment is an implant comprising a first region, a second region and a third region. The first region has a proximal region and a distal region. The first region comprises a flared proximal stent framework which tapers radially inwardly in a distal direction. The second region has a proximal region and a distal region. The second region comprises a flexible sleeve extending distally from the distal region of the first region. The third region has a proximal region and a distal region. The third region comprises a distal stent framework having an outer diameter less than that of the flared proximal stent framework at the proximal region adjacent to the first region, and the distal stent framework extends distally from the distal region of the second region. The flexible sleeve is configured to extend through a natural valve or sphincter and contract itself in response to radially applied forces.

[0006] Additionally or alternatively, in another embodiment, the implant includes a first retrieval suture that at least partially collapses the implant for removal from the body cavity.

[0007] Additionally or alternatively, in another embodiment, the first retrieval suture is interwoven with the flared proximal stent framework and the distal stent framework.

[0008] Additionally or alternatively, in another embodiment, the first retrieval suture includes a first suture loop interwoven with a flared proximal stent frame in a proximal region adjacent to the first region, a second suture loop interwoven with a distal stent in a proximal region adjacent to the third region, and a connecting suture portion extending between and coupled to the first suture loop and the second suture loop.

[0009] Additionally or alternatively, in another embodiment, the proximal force applied to the first retrieval suture is configured to locally collapse the flared proximal stent framework adjacent the proximal region of the first region.

[0010] Additionally or alternatively, in another embodiment, once the outer diameter of the flared proximal stent framework adjacent to the proximal region of the first region is locally contracted, the distal stent framework is configured to begin contracting simultaneously with further contraction of the proximal stent framework.

[0011] Additionally or alternatively, in another embodiment, the connecting suture portion includes a slack portion configured to be tightened when the flared proximal stent framework partially contracts before the distal stent framework begins to contract.

[0012] Additionally or alternatively, in another embodiment, the first retrieval suture includes a first suture ring interwoven with a distal stent frame in a distal region adjacent to the third region, a second suture ring interwoven with a flared proximal stent frame in a distal region adjacent to the first region, and a connecting suture portion extending between and connected to the first suture ring and the second suture ring.

[0013] Additionally or alternatively, in another embodiment, the distal force applied to the first retrieval suture is configured to locally contract the distal stent framework adjacent to the distal region of the third region.

[0014] Additionally or alternatively, in another embodiment, the connecting suture portion includes a slack portion configured to be tightened when the distal stent framework is partially contracted before the flared proximal stent framework begins to contract.

[0015] Additionally or alternatively, in another embodiment, the implant includes a second retrieval suture.

[0016] Additionally or alternatively, in another embodiment, the second retrieval suture is interwoven with the flared proximal and distal stent frames.

[0017] Additionally or alternatively, in another embodiment, at least one of the first retrieval suture or the second retrieval suture is configured to at least partially collapse the flared proximal stent framework prior to collapsing the distal stent framework.

[0018] Additionally or alternatively, in another embodiment, at least one of the first retrieval suture or the second retrieval suture is configured to at least partially collapse the distal stent framework prior to collapsing the flared proximal stent framework.

[0019] Additionally or alternatively, in another embodiment, the flared proximal stent framework has an outer contour configured to conform to the outlet of the stomach.

[0020] Additionally or alternatively, in another embodiment, the outer diameter of the flared proximal stent framework of the proximal region adjacent to the first region is in the range of about 25 millimeters (mm) to about 50 mm.

[0021] Additionally or alternatively, in another embodiment, the outer diameter of the distal stent framework is in the range of about 15 millimeters (mm) to about 25 mm.

[0022] Another illustrative embodiment is an implant comprising an elongated tubular member. The elongated tubular member comprises a proximal support, a flexible sleeve and a distal support. The proximal support has a proximal region and a distal region. The proximal support tapers from a first outer diameter adjacent to the proximal region to a second smaller outer diameter adjacent to the distal region. The flexible sleeve has a proximal region and a distal region. The flexible sleeve extends distally from the distal region of the expanded proximal support. The distal support has a proximal region and a distal region. The outer diameter of the distal support is less than the first outer diameter of the proximal support and extends distally from the distal region of the flexible sleeve. A first retrieval suture is interwoven with the proximal support and the distal support. The flexible sleeve is configured to extend through a natural valve or sphincter and self-contract in response to radially applied forces.

[0023] Additionally or alternatively, in another embodiment, the proximal stent is configured to be positioned at the gastric outlet of the stomach, and the flexible sleeve is configured to be positioned through the pyloric sphincter.

[0024] Additionally or alternatively, in another embodiment, the radial force applied is a natural effect of the pyloric sphincter.

[0025] Additionally or alternatively, in another embodiment, the first retrieval suture is configured to at least partially collapse the proximal stent before the distal stent begins to collapse.

[0026] Additionally or alternatively, in another embodiment, the first retrieval suture is configured to at least partially collapse the distal stent before the proximal stent begins to collapse.

[0027] Another exemplary embodiment is a method for removing or repositioning an intraluminal implant. The method includes actuating an end of a retrieval suture in a first direction. The retrieval suture is interwoven within an end region of a first stent of the intraluminal implant and an end region of a second stent of the intraluminal implant. The first stent and the second stent are separated and connected by a flexible polymer sleeve. The end region of the first stent is configured to locally contract before the end of the second stent begins to contract.

[0028] Additionally or alternatively, in another embodiment, the retrieval suture includes a first circumferential ring extending around the end region of the first stent, a second circumferential ring extending around the end of the second stent, and a connecting suture portion extending between the first circumferential ring and the second circumferential ring, wherein the slack portion of the connecting suture portion is tightened when the end region of the first stent locally contracts before the end of the second stent begins to contract.

[0029] Additionally or alternatively, in another embodiment, the first stent is connected to the second stent only through the flexible polymer sleeve.

[0030] The above summary of exemplary embodiments is not intended to describe each disclosed embodiment or every implementation of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention may be more fully understood by considering the following detailed description of various embodiments in conjunction with the accompanying drawings, in which:

[0032] Figure 1 is a side view of an exemplary implant;

[0033] Figure 2 is a side view of another exemplary implant;

[0034] Figure 3 is a side view of another exemplary implant;

[0035] Figure 4 is a side view of another exemplary implant;

[0036] Figure 5 is a side view of another exemplary implant;

[0037] Figure 6 for Figure 1 A schematic side view of an implant of , wherein the retrieval suture is in a first configuration;

[0038] Figure 7 for Figure 6 1. A schematic side view of an implant of FIG. 1, wherein the implant is in a partially collapsed configuration;

[0039] Figure 8 for Figure 6A side view of an exemplary implant of , wherein the implant is in a fully collapsed configuration;

[0040] Fig. 9 for Figure 1 A side view of an exemplary implant of wherein the retrieval suture is in a second configuration;

[0041] Fig.10 for Fig. 9 A side view of an exemplary implant of , wherein the implant is in a partially collapsed configuration;

[0042] Fig.11 for Fig. 9 A side view of an exemplary implant of , wherein the implant is in a fully collapsed configuration;

[0043] Fig.12 a side view of another exemplary implant retrieval suture;

[0044] Fig.13 for Fig.12 A side view of an exemplary implant of , wherein the implant is in a partially collapsed configuration;

[0045] Fig.14 for Fig.12 A side view of an exemplary implant of , wherein the implant is in a fully collapsed configuration;

[0046] Although the content of the present invention can be subjected to various modifications and alternative forms, its specific content has been shown in the accompanying drawings by way of example and will be described in detail. However, it should be understood that it is not intended to limit the aspects of the present invention to the specific embodiments described. On the contrary, it is intended to cover all modifications, equivalents and alternative forms that belong to the spirit and scope of the present invention. DETAILED DESCRIPTION

[0047] For the following defined terms, these definitions shall apply unless a different definition is given in the claims or elsewhere in this specification.

[0048] Herein, all numerical values ​​are assumed to be modified by the term "about", whether or not explicitly stated. The term "about", in the context of numerical values, generally refers to a range of numbers that one skilled in the art considers to be equivalent to the stated numerical value (e.g., having the same function or result). In many cases, the term "about" can mean a number that includes rounding to the nearest significant number.

[0049] The recitation of numerical ranges by endpoints includes all numbers within that range (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0050] Although some suitable sizes, ranges and / or values ​​are disclosed for various components, features and / or specifications, those skilled in the art, informed by the present disclosure, will appreciate that the desired sizes, ranges and / or values ​​may vary from those explicitly disclosed.

[0051] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and / or" unless the content clearly dictates otherwise.

[0052] In the present invention, "proximal side" refers to the end closer to the device operator during use, and "distal side" refers to the end farther from the device operator during use.

[0053] The following detailed description should be read with reference to the drawings, wherein similar elements in different drawings are numbered the same. The detailed description and drawings are not necessarily drawn to scale, describe exemplary embodiments, and are not intended to limit the scope of the disclosure. The exemplary embodiments described are intended to be examples only. Unless expressly stated to the contrary, selected features of any exemplary embodiment may be incorporated into another embodiment.

[0054] It should be noted that references in the specification to "one embodiment", "some embodiments", "other embodiments", etc. indicate that the described embodiments may include a particular characteristic, structure, or feature, but every embodiment may not necessarily include the particular characteristic, structure, and / or feature. Moreover, such phrases do not necessarily refer to the same embodiment. In addition, when a particular characteristic, structure, or feature is described as being associated with one embodiment, it should be understood that the characteristic, structure, or feature may also be used in association with other embodiments, whether or not explicitly described, unless clearly stated to the contrary.

[0055] Gastric outlet obstruction (GOO) is the clinical and pathophysiological consequence of any disease process that produces a mechanical impediment to gastric emptying. The presence of GOO can be divided into disease conditions that affect the antrum and pylorus resulting in pyloric dysfunction or proximal duodenal outflow restriction. Clinical conditions such as peptic ulcer disease (PUD), pyloric stenosis, and gastric polyps represent the causes of the former, and pancreatic cancer, Angle's carcinoma, duodenal cancer, and bile duct cancer represent the causes of the latter. In some cases, GOO can be treated directly by stenting the site using a gastrointestinal (GI) self-expanding stent. However, placement of a stent across the pyloric valve may place the pylorus in a persistently open position. However, this may result in gastric leaks into the duodenum. Alternative stent designs are needed to open even blockages while preserving the natural function of the pylorus.

[0056] Figure 1A side view of an exemplary intracavitary implant 10 including multiple regions is shown, and the implant 10 includes a first region or proximal region 12, a second region or middle region 14, a third region or middle region 16, and a fourth or distal region 18. Although the exemplary implant 10 is shown and described as having four regions 12, 14, 16, 18, it is envisioned that the implant 10 may include any desired number of regions, such as but not limited to one, two, three, four or more. In addition, regions 12, 14, 16, 18 may be any combination of desired structures and materials. In some cases, the implant 10 may include features (e.g., anti-migration flaring, fixing nails, sutures, etc.) that prevent the implant 10 from being displaced and / or migrated distally / proximally once the implant 10 is positioned and expanded in the body cavity. The implant 10 may include a cavity 48 that runs through the length of the implant 10 completely, such as from the proximal end 24 of the first region 12 to the distal end 46 of the fourth region 18.

[0057] In some cases, the first region 12 can be in the form of a stent 20, which includes an elongated tubular stent framework 22 defining a cavity. The stent 20 can be completely, substantially or partially covered with a polymer covering, such as a coating (not explicitly shown). The covering can be provided on the inner surface and / or outer surface of the stent 20 as desired. When the polymer covering is provided in this way, the growth of tissue can be reduced or eliminated and / or the insertion of food into the cavity through the gaps of the stent 20 can be reduced. It is conceivable that leaving a portion of the outer edge or surface uncovered can create a hyperplastic area, thereby establishing a seal. The stent 20 can include regions of different diameters. For example, the stent 20 can include a flared (e.g., enlarged relative to other parts of the stent 20) proximal region 24, which tapers radially inward to a distal region. Although not explicitly shown, if desired, the stent 20 can include a region of constant diameter or increased diameter (e.g., in the distal direction). The stent framework 22 can expand between a radially contracted delivery configuration and a radially expanded deployment configuration. The expandable configuration can fix the implant 10 in a desired position in the body cavity.

[0058] In some cases, the third region 16 can be in the form of a stent 28 that includes an elongated tubular stent frame 30 that defines a cavity. The stent 28 can be completely, substantially, or partially covered with a polymer covering, such as a coating (not explicitly shown). The covering can be provided on the inner surface and / or outer surface of the stent 28 as desired. When the polymer covering is provided in this way, tissue growth and / or food embedding into the cavity through the gaps of the stent 28 can be reduced or eliminated. The stent 28 can have a uniform outer diameter from its proximal region 32 to its distal region 34. However, if desired, the stent 28 may include regions of different diameters. The stent frame 30 can expand between a radially contracted delivery structure and a radially expanded deployment structure. The expandable structure can secure the implant 10 in a desired position in the body cavity. Although not explicitly shown, in some embodiments, the distal stent 28 can extend distally to the distal end of the implant 10. About Figure 2-5 Some additional but non-limiting alternative configurations are shown and described.

[0059] The stent frames 22, 30 may have an interwoven structure made of a plurality of filaments. In some embodiments, the stent frames 22, 30 may be woven with a single filament, such as ULTRAFLEX manufactured and sold by Boston Scientific Corp. TM In other embodiments, the stent framework 22, 30 may be braided with several filaments, such as those manufactured and sold by Boston Scientific Corporation. and In another embodiment, the stent framework 22, 30 may be a knotted type, such as PRECISION COLONIC manufactured by Boston Scientific Corporation. TM In another embodiment, the stent framework 22, 30 may be laser cut, such as the EPIC manufactured by Boston Scientific Corporation. TM Stent. It is contemplated that the stent frames 22, 30 may be formed to have the same structure as one another or to have different structures than one another.

[0060] It is contemplated that the stent frames 22, 30 may be made of many different materials as desired, such as, but not limited to, metals, metal alloys, shape memory alloys, and / or polymers, to enable the stents 20, 28 to expand into shape when properly positioned within the body. The materials of the stent frames 22, 30 may be the same or different, as desired. In some cases, a material may be selected that enables the stents 20, 28 to be relatively easily removed. For example, the stent frames 22, 30 may be formed of alloys, such as, but not limited to, nitinol and Depending on the structural material selected, the stents 20, 28 can be self-expanding (i.e., configured to automatically expand radially when not constrained). In some embodiments, fibers can be used to make the stent framework 22, 30, which can be composite fibers, for example, having a shell made of nitinol with a platinum core. It is further contemplated that the stent framework 22, 30 can be formed from polymers including, but not limited to, polyethylene terephthalate (PET). In some embodiments, the stents 20, 28 can be self-expanding, while in other embodiments, the stents 20, 28 can be expanded by an expansion device (e.g., but not limited to, a balloon inserted into the cavity 48 of the implant 10). As used herein, the term "self-expanding" refers to the tendency of the stent to return to a preset diameter when not constrained by an external biasing force (e.g., but not limited to, a delivery catheter or sheath).

[0061] One or both of stents 20, 28 may include a one-way valve, such as an elastomeric slit valve or duckbill valve, positioned within lumen 48 thereof to prevent retrograde flow of fluid or other material, such as gastrointestinal fluids.

[0062] In some cases, the second portion 14 can be in the form of a proximal flexible sleeve 36 and the fourth portion 18 can be in the form of a distal flexible sleeve 42. The proximal sleeve 36 can extend between the distal end of the proximal stent 20 and the proximal end of the distal stent 28. For example, the proximal sleeve 36 can be connected, attached or fixed to the first stent adjacent to the proximal region 38 of the sleeve 36 or the distal region 26 of the proximal stent 20. The proximal sleeve 36 can also be connected, attached or fixed to the proximal region 32 of the second stent adjacent to the distal region 40 of the proximal sleeve 36 or the distal stent 28. In some cases, the proximal sleeve 36 can overlap part or all of the proximal stent 20 and / or part or all of the distal stent 28. In some cases, the proximal sleeve 36 can be free of any structural components that tend to keep the cavity 48 through the sleeve 36 open, thereby allowing the sleeve 36 to collapse inwardly on its own when subjected to the force of the pyloric valve closing cavity 48. The distal sleeve 42 can be connected, attached or fixed to the distal region 44 of the second support or distal support 28 of the proximal region adjacent to the sleeve 42, and extend distally to the distal region 46. In some cases, the distal sleeve 42 can overlap part or all of the distal support 28. It is conceivable that the sleeves 36, 42 can form a single flexible membrane or a single unit structure as needed. In some embodiments, the sleeves 36, 42 can extend the length of the implant 10 locally, substantially or completely, and cover all other parts (external surface and / or internal surface) of the implant 10, including the support 20, 28. In other words, although the regions 12, 14, 16, 18 have been described as support 20, 28 or sleeves 36, 42, each region may include one or two of the framework structure and the flexible sleeve structure. The sleeves 36, 42 can be fixed to one or two of the support 20, 28 by adhesives or other methods known in the art (including but not limited to thermal methods, mechanical methods, etc.).

[0063] The sleeves 36, 42 can each have an elongated tubular shape defining a cavity. The cavity of the stent 20, 28 and the flexible sleeves 36, 42 can be fluidically connected to form the cavity 48 of the implant 10. As required, it is conceivable that one or more regions 12, 14, 16, 18 of the implant 10 may include more than one cavity. The sleeves 36, 42 can be thin flexible membranes that are easy to shrink on their own. For example, when the implant 10 is deployed in a body cavity with a natural valve or sphincter, one or two sleeves can be configured to shrink on their own under the radial force applied by the natural valve or sphincter. However, one or two of the sleeves 36, 42 can provide radial support to keep it in an expanded configuration. Some examples and discussion of exemplary supports may be found in co-pending patent application Ser. No. 62 / 419,707, filed Nov. 9, 2016, entitled DEPLOYABLE SLEEVES AND RELATED METHODS, the disclosure of which is incorporated herein by reference.

[0064] The sleeves 36, 42 may include one or more of the following polymer materials: polyethylene, polypropylene, polystyrene, polyester, bioabsorbable plastics (e.g., polylactic acid), polycarbonate, polyvinyl chloride, polyacrylate, acrylate, polysulfone, polyetheretherketone, thermoplastic elastomer, thermosetting elastomer (e.g., silicone), polyparaxylene (parylene), fluoropolymers (e.g., polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), poly(vinylidene fluoride-co-hexafluoropropylene) (PVDFHFP), bioplastics (e.g., cellulose acetate). The sleeves 36, 42 may additionally or alternatively include one or more of the following: polyurethane and its copolymers, ethylene-acetic acid Polyethylene esters, polyethylene terephthalate (PET), polyolefins, cellulosics, polyamides, acrylonitrile-butadiene-styrene copolymers, styrene-isoprene-butadiene (SIBS) block copolymers, acrylates, poly(ethylene glycol-lactide copolymers), thermoplastic polyurethane elastomers (Tecothane), nylon elastomers (PEBAX), poly(γ-caprolactone), poly(γ-hydroxybutyrate), polydioxanone, poly(γ-ethylglutamate), polyimide, poly(orthoesters), and / or polyanhydrides. Mixtures of the above polymers may also be used, such as, but not limited to, those produced by AdvanSource Biomaterials, Inc., located in Wilmington, Massachusetts. A range of biodurable aromatic polycarbonate based thermoplastic polyurethanes.

[0065] In further details, implant 10 can be generally cylindrical, although this is not necessary, is basically flexible, and is of suitable size, so that it can be accommodated in the digestive tract. It is conceivable that various shapes, sizes and designs of implants can be constructed according to the size and geometry of the cavity in which implant 10 must be placed. In various examples, implant 10 can have a length of 3-12 inches, 3-6 inches, 0.5-20 feet (0.15-6.1 meters), 3-5 feet (0.9-1.5 meters) or about 2-4 feet (0.6-1.2 meters). However, in some cases, the length of implant 10 can be less than 0.5 feet (0.15 meters) or greater than 20 feet (6.1 meters).

[0066] In an illustrative example, the size of the implant 10 can be set to be positioned in the gastric outlet, extending through the pylorus and into the duodenum to treat, for example, gastric outlet obstruction. In such an example, the size of the proximal stent 20 can be set to prevent the implant 10 from migrating distally through the gastric outlet. For example, the proximal region 24 of the proximal stent 20 can have an outer diameter 50 in the range of about 25 millimeters (mm) to about 50 mm. It is conceivable that the shape of the proximal stent 20 can be formed to match or roughly conform to the shape of the gastric outlet. The proximal sleeve 36 can be configured to extend through the pylorus and can have a length 54 in the range of about 6 mm to about 15 mm. The size of the distal stent 28 and the distal sleeve 42 can be set to be positioned in the duodenal bulb and the duodenum, respectively, and can have an outer diameter 52 in the range of about 15 mm to about 25 mm. The distal stent 28 and the distal sleeve 42 can have a length 56 in the range of about 60 mm to about 150 mm together. When the distal support 28 extends distally to the distal end of the implant 10, the distal support 28 can have a length 56 in the range of about 60 mm to about 150 mm. This is just one example. It is contemplated that the proximal sleeve 36 and / or the distal sleeve 42 can be positioned across other valves or sphincter regions, with the proximal and / or distal supports 20, 28 being sized and shaped for the adjacent anatomical structures.

[0067] Once implanted in the patient, the stents 20, 28 can apply radial external forces to help fix the implant 10 to the body cavity. The implant 10 can be positioned in the antrum-pylorus-duodenum, esophagus, gastroesophageal junction (GEJ) region (e.g., at or near the cardia, the sleeve 24 extends to the esophagus), or at or near the pylorus, the sleeve 24 extends through the stomach or other parts of the gastrointestinal system. In one example, the implant 10 can be positioned so that the proximal stent 20 is positioned at the gastric outlet, and the proximal sleeve 36 bridges the pylorus. The flared structure of the proximal stent 20 can utilize the stomach to fix the implant 10 and serve as an anti-migration mechanism for the implant 10. For example, the large outer diameter 50 of the proximal end 24 of the proximal stent 20 can engage with the gastric outlet to prevent or limit the movement of the implant 10. The distal stent 28 can be placed in the duodenal bulb, and the distal sleeve 42 can extend into the duodenum. The proximal sleeve 36 may be coupled to both the proximal stent 20 and the distal stent 28 such that the relative position of each portion is fixed.

[0068] In some cases, the function of the pyloric valve may not be affected or degraded by the disease state that causes the gastric outlet obstruction. In this case, it may be necessary to open the obstruction while still allowing the normal function of the pyloric valve. As described above, the proximal sleeve 36 can be formed of a flexible material. In other words, the proximal sleeve 36 can be unaffected by any structure configured to apply radial external forces to the surrounding tissue, and can self-contract under the radial forces applied by the natural valve or sphincter. This allows the pyloric valve to function (e.g., open and close) in a natural manner. The distal stent 28 can be positioned near the gastric outlet obstruction. The stent frame 30 of the distal stent 28 can be configured to have sufficient radial force (e.g., apply sufficient radial external force) to open the obstruction caused by the disease state.

[0069] Figure 2The side view of another exemplary implant 100 comprising multiple regions is shown, and this implant 100 comprises first area or proximal region 102, second area or middle area 104 and third area or distal region 106.Exemplary implant 100 can be similar to above-mentioned implant 10 in form and function.Although exemplary implant 100 is shown and described as having three regions 102,104,106, it is envisioned that implant 100 can comprise required any number of regions, such as but not limited to one, two, three, four or more.Further, region 102,104,106 can be any combination of required structure and material.In some cases, implant 100 can comprise feature (for example, anti-migration flaring, fixing nail, suture etc.) to prevent distal / proximal displacement and / or migration of implant 100, once implant 100 is positioned and expanded in body cavity. The implant 100 may include a cavity 108 extending from a proximal end 114 of the first region 102 to a distal end 124 of the third region 106 .

[0070] In some cases, the first region 102 can be in the form of a stent 110, which includes an elongated tubular stent frame 112 defining a lumen, and the form and function of the stent 110 are similar to the proximal stent 20 described above. The stent 110 can be completely, substantially or partially covered with a polymer covering, such as a coating (not explicitly shown). As desired, the covering can be provided on the inner surface and / or outer surface of the stent frame 112. When the polymer covering is provided in this way, tissue ingrowth and / or food impaction can be reduced or eliminated. The stent 110 may include regions of different diameters. For example, the stent 110 may include a flared (e.g., enlarged relative to other parts of the stent 110) proximal region 114 that tapers radially inwardly to a distal region 116 in the distal direction. Although not explicitly shown, if desired, the stent 110 may include a region of constant diameter or increased diameter (e.g., increased in the distal direction). The stent frame 112 can expand between a radially contracted delivery configuration and a radially expanded deployment configuration. The expanded configuration may secure the implant 100 at a desired location within the body lumen.

[0071] In some cases, the third region 106 can be in the form of a stent 118, which includes an elongated tubular stent framework 120 defining a cavity, and the form and function of the stent 118 are similar to the distal stent 28 described above. The stent 118 can be completely, substantially or partially covered with a polymer covering, such as a coating (not explicitly shown). As required, the covering can be provided on the inner surface and / or outer surface of the stent framework 120. When the polymer covering is provided in this way, tissue ingrowth and / or food impaction can be reduced or eliminated. The stent 118 can have a uniform outer diameter from its proximal region 122 to its distal region 124. However, if desired, the stent 118 can include regions of different diameters. The stent framework 120 can expand between a radially contracted delivery configuration and a radially expanded deployment configuration. The deployment configuration can fix the implant 100 in a desired position in the body cavity. Although not explicitly shown, in some embodiments, the distal stent 118 can extend distally to the distal end of the implant 100.

[0072] In some cases, the second portion 104 can be in the form of a flexible sleeve 126. The sleeve 126 can extend between the distal end of the proximal stent 110 and the proximal end of the distal stent 118. For example, the sleeve 126 can be connected, attached or fixed to the first stent of the proximal region 128 adjacent to the sleeve 126 or the distal region 116 of the proximal stent 110. The sleeve 126 can also be connected, attached or fixed to the second stent 118 of the distal region 130 adjacent to the sleeve 126 or the proximal region 122 of the distal stent 118. In some cases, the sleeve 126 can overlap a portion or all of the proximal stent 110 and / or a portion or all of the distal stent 118. The difference is that the sleeve 126 can extend from the proximal region 114 of the proximal stent 110 to the distal region 124 of the distal stent 118 so that the implant 100 is completely covered. Alternatively, and / or additionally, one or both of the proximal support 110 and the distal support 118 can be covered with a material or structure different from the sleeve 126 to provide a fully covered implant 100. The sleeve 126 can be fixed to one or both of the supports 110, 118 by adhesives or other methods known in the art (including but not limited to thermal methods, mechanical methods, etc.).

[0073] The sleeve 126 can have an elongated tubular shape defining a cavity, and its form or function can be similar to the sleeves 36, 42 described above. The cavities of the stents 110, 118 and the flexible sleeve 126 can be fluidically connected to form the cavity 108 of the implant 100. As required, it is envisioned that one or more regions 102, 104, 106 of the implant 100 can include more than one cavity. The sleeve 126 can be a thin flexible membrane that is easily self-contracting. However, in some cases, the sleeve 126 can provide radial support.

[0074] The sleeve 126 may include one or more longitudinally extending slots 132 extending through the thickness of the sleeve 126. Removing material to form the slots 132 may allow the connecting element to remain between the proximal stent 110 and the distal stent 118 while increasing the deformability and / or movability of the sleeve 126. Thus, when the sleeve 126 is positioned across a valve or sphincter, such as but not limited to the pyloric valve, the reduced amount of material placed across the valve region may further allow for normal valve function. The sleeve 126 may include any number of longitudinally extending slots 132 desired, such as but not limited to one, two, three, four, or more. The slots 132 may be uniformly positioned around the circumference of the sleeve 126 (e.g., with uniform distances between adjacent slots 132) or eccentrically positioned around the circumference of the sleeve 126 (e.g., with unequal distances between adjacent slots 132). Although the slot 132 has been described as extending longitudinally (e.g., along the longitudinal axis of the implant 100), it is contemplated that the slot 132 may extend along a non-parallel angle relative to the longitudinal axis of the implant 100. For example, the slot 132 may extend in a helical manner around the circumference of the sleeve 126.

[0075] In one example, the implant 100 may be sized to be positioned within the gastric outlet, extending through the pylorus and into the duodenum to treat, for example, gastric outlet obstruction. In such an example, the proximal stent 110 may be sized to prevent the implant 100 from migrating distally through the gastric outlet. For example, the proximal region 114 of the proximal stent 110 may have an outer diameter 134 in the range of about 25 millimeters (mm) to about 50 mm. It is contemplated that the shape of the proximal stent 110 may be formed to match or substantially conform to the shape of the gastric outlet. The sleeve 126 may be configured to extend through the pylorus and may have a length 136 in the range of about 6 mm to about 15 mm. The distal stent 118 may be sized to be positioned within the duodenal bulb and the duodenum, respectively, and may have an outer diameter 138 in the range of about 15 mm to about 25 mm. The distal stent 118 may have a length 140 in the range of about 60 mm to about 150 mm. This is just an example. It is contemplated that the sleeve 126 may be positioned across other valves or sphincter regions, with the proximal and / or distal stents 110, 118 sized and shaped for the adjacent anatomical structures.

[0076] Once implanted in the patient, the stents 110, 118 can apply radial external forces to help fix the implant 100 to the body cavity. The implant 100 can be positioned in the esophagus, gastroesophageal junction (GEJ) area, or at or near the pylorus, and the sleeve 114 extends through the stomach or other parts of the gastrointestinal system. In one example, the implant 100 can be positioned so that the proximal stent 110 is positioned at the stomach outlet, and the sleeve 126 bridges the pylorus. The flared structure of the proximal stent 110 can use the stomach to anchor the implant 100 and serve as an anti-migration mechanism of the implant 100. For example, the large outer diameter 134 of the proximal end 114 of the proximal stent 110 can engage the stomach outlet to prevent or limit the movement of the implant 100. The distal stent 118 can be placed in the duodenal bulb and can extend to the duodenum. The sleeve 126 can be connected to the proximal stent 110 and the distal stent 118 at the same time so that the relative position of each part is fixed.

[0077] In some cases, the function of the pyloric valve may not be affected or degraded by the disease state causing the gastric outlet obstruction. In this case, it may be necessary to open the obstruction while still allowing the normal function of the pyloric valve. As described above, the sleeve 126 can be formed of a flexible material that can become more flexible or pliable by adding a groove 132. In other words, the sleeve 126 and therefore the length of the intermediate region 104 between the proximal stent 110 and the distal stent 118 can be unaffected by any structure configured to apply radial external forces to the surrounding tissue. This can enable the pyloric valve to function (e.g., open and close) in a natural manner. The distal stent 118 can be positioned near the gastric outlet obstruction. The stent frame 120 of the distal stent 118 can be configured to have sufficient radial force (e.g., apply sufficient radial external force) to open the obstruction caused by the disease state.

[0078] Figure 3 A side view of another exemplary implant 150 including multiple regions is shown, and the implant 150 includes a first region 152, a second region 154, and a third region 156. The exemplary implant 150 can be similar to the above-mentioned implant 10 in form and function. Although the exemplary implant 150 is shown and described as having three regions 152, 154, 156, it is conceivable that the implant 150 can include any desired number of regions, such as but not limited to one, two, three, four or more. Further, regions 152, 154, 156 can be any combination of desired structures and materials. In some cases, the implant 150 can include features (e.g., anti-migration flaring, fixing nails, sutures, etc.) that prevent the implant 150 from being displaced and / or migrated to the distal / proximal side once the implant 150 is positioned and expanded in the body cavity. The implant 150 can include a cavity 158 extending from the proximal end 164 of the first region 152 to the distal end 174 of the third region 156.

[0079] In some cases, the first region 152 can be in the form of a stent 160 that includes an elongated tubular stent frame 162 defining a lumen, which can be similar in form and function to the proximal stent 20 described above. The stent 160 can be completely, substantially, or partially covered with a polymer covering, such as a coating (not explicitly shown). The covering can be provided on the inner surface and / or outer surface of the stent frame 162 as desired. When the polymer covering is provided in this way, tissue growth and / or food impaction can be reduced or eliminated. The stent 160 may include regions of different diameters. For example, the stent 160 may include a flared (e.g., enlarged relative to the rest of the stent 160) proximal region 164 that tapers radially inwardly in the distal direction to a distal region 166. Although not explicitly shown, if desired, the stent 160 may include a region of constant diameter or increased diameter (e.g., in the distal direction). The stent frame 162 can expand between a radially contracted delivery configuration and a radially expanded deployment configuration. The expanded configuration secures the implant 150 at a desired location within the body lumen.

[0080] In some cases, the third region 156 can be in the form of a stent 168, which includes an elongated tubular stent framework 170 defining a cavity, which can be similar in form and function to the distal stent 28 described above. The stent 168 can be completely, substantially or partially covered with a polymer covering, such as a coating (not explicitly shown). For example, a local covering can be used to cause hyperplasia for fixation, or, for example, for the bile duct or other passages. As required, the covering can be provided on the inner surface and / or outer surface of the stent framework 170. When a polymer covering is provided in this way, tissue growth and / or food impaction can be reduced or eliminated. The stent 168 can have a uniform outer diameter from its proximal region 172 to its distal region 174. However, if desired, the stent 168 can include regions of different diameters. The stent framework 170 can expand between a radially contracted delivery structure and a radially expanded deployment structure. The deployment structure can fix the implant 150 in a desired position in the body cavity. Although not explicitly shown, in some embodiments, the distal support 168 can extend distally to the distal end of the implant 150.

[0081] In some cases, the second portion 154 can be in the form of a flexible sleeve 176. The sleeve 176 can extend between the distal end of the proximal stent 160 and the proximal end of the distal stent 168. For example, the sleeve 176 can be connected, attached or fixed to the distal region 116 of the first stent or proximal stent 160 adjacent to the proximal region 178 of the sleeve 176. The sleeve 176 can also be connected, attached or fixed adjacent or distal to the proximal region 172 of the second stent or distal stent 168, which is adjacent to the distal region 180 of the sleeve 176. In some cases, the sleeve 176 can overlap a portion or all of the proximal stent 160 and / or a portion of the distal stent 168. In other words, the sleeve 176 can extend from the proximal region 164 of the proximal stent 160 to a position proximal to the distal region 174 of the distal stent 168, so that the implant 150 is not completely covered. For example, at least a portion of the distal stent 168 may be a bare stent. This may allow tissue growth to further secure the implant 150. In some cases, all or part of the proximal stent 160 may be bare. Alternatively, and / or additionally, one or both of the proximal stent 160 and the distal stent 168 may be covered with a material or structure different from that of the sleeve 176 to provide a partially covered implant 150. The sleeve 176 may be fixed to one or both of the stents 160, 168 by adhesives or other methods known in the art (including but not limited to thermal methods, mechanical methods, etc.).

[0082] The sleeve 176 can have an elongated tubular shape defining a cavity, and its form or function can be similar to the sleeves 36, 42 described above. The cavities of the stents 160, 168 and the flexible sleeve 176 can be fluidly connected to form the cavity 158 of the implant 150. As desired, it is contemplated that one or more regions 152, 154, 156 of the implant 150 can include more than one cavity. The sleeve 176 can be a thin flexible membrane that is easily self-contracting. However, in some cases, the sleeve 176 can provide radial support.

[0083] The sleeve 176 may include one or more holes 182 extending through the thickness of the sleeve 176. For example, the sleeve 176 may have a mesh structure. Removing material to form the holes 182 allows the connecting element to remain between the proximal support 160 and the distal support 168, while increasing the deformability and / or movability of the sleeve 176. Therefore, when the sleeve 176 is positioned through a valve or sphincter, such as but not limited to the pyloric valve, the reduced amount of material placed through the valve area can further allow normal valve function. The sleeve 176 may include any number of holes 182 required, such as but not limited to one, two, three, ten, twenty, fifty or more. The holes 182 may be uniformly positioned around the circumference of the sleeve 176 or the length of the sleeve 176 (e.g., with uniform distances between adjacent holes 182) or eccentrically positioned around the circumference of the sleeve 176 or the length of the sleeve 176 (e.g., with unequal distances between adjacent holes 182).

[0084] In an illustrative example, the size of the implant 150 can be set to be positioned in the gastric outlet, extending through the pylorus and into the duodenum to treat, for example, gastric outlet obstruction. In such an example, the size of the proximal stent 160 can be set to prevent the implant 150 from migrating distally through the gastric outlet. For example, the proximal region 164 of the proximal stent 160 can have an outer diameter 184 in the range of about 25 millimeters (mm) to about 50 mm. It is conceivable that the shape of the proximal stent 160 can be formed to match or roughly conform to the shape of the gastric outlet. The sleeve 176 can be configured to extend through the pylorus and can have a length 186 in the range of about 6 mm to about 15 mm. The size of the distal stent 168 can be set to be positioned in the duodenal bulb and the duodenum, respectively, and can have an outer diameter 188 in the range of about 15 mm to about 25 mm. The distal stent 168 can have a length 190 in the range of about 60 mm to about 150 mm. This is just an example. It is contemplated that the sleeve 176 may be positioned across other valves or sphincter regions, with the proximal and / or distal stents 160, 168 sized and shaped for the adjacent anatomical structures.

[0085] Once implanted in the patient, the stents 160, 168 can apply radial external forces to help fix the implant 150 to the body cavity. The implant 150 can be positioned in the esophagus, gastroesophageal junction (GEJ) area, or at or near the pylorus, and the sleeve 164 extends through the stomach or other parts of the gastrointestinal system. In one example, the implant 150 can be positioned so that the proximal stent 160 is positioned at the stomach outlet, and the sleeve 176 bridges the pylorus. The flared structure of the proximal stent 160 can use the stomach to anchor the implant 150 and serve as an anti-migration mechanism for the implant 150. For example, the large outer diameter 184 of the proximal end 164 of the proximal stent 160 can engage the stomach outlet to prevent or limit the movement of the implant 150. The distal stent 168 can be placed in the duodenal bulb and can extend into the duodenum. The sleeve 176 can be connected to the proximal stent 160 and the distal stent 168 at the same time so that the relative position of each part is fixed.

[0086] In some cases, the function of the pyloric valve may not be affected or degraded by the disease state causing the gastric outlet obstruction. In this case, it may be necessary to open the obstruction while still allowing the normal function of the pyloric valve. As described above, the sleeve 176 can be formed of a flexible material that can become more flexible or pliable by increasing the hole 182. In other words, the sleeve 176 and therefore the length of the intermediate region 154 between the proximal stent 160 and the distal stent 168 can be unaffected by any structure configured to apply radial external forces to the surrounding tissue. This can allow the pyloric valve to function in a natural manner (e.g., opening and closing). The distal stent 168 can be positioned near the gastric outlet obstruction. The stent frame 170 of the distal stent 168 can be configured to have sufficient radial force (e.g., apply sufficient radial external force) to open the obstruction caused by the disease state.

[0087] Figure 4 A side view of another exemplary implant 200 including multiple regions is shown, and the implant 200 includes a first region 202, a second region 204 and a third region 206. The exemplary implant 200 can be similar to the above-mentioned implant 10 in form and function. Although the exemplary implant 200 is shown and described as having three regions 202, 204, 206, it is conceivable that the implant 200 can include any desired region of any number, such as but not limited to one, two, three, four or more. Further, regions 202, 204, 206 can be any combination of desired structure and material. In some cases, the implant 200 can include features (e.g., anti-migration flaring, fixing nails, sutures, etc.) that prevent the implant 200 from being displaced and / or migrated to the distal / proximal side once the implant 200 is positioned and expanded in the body cavity. The implant 200 can include a cavity 208 extending from the proximal end 214 of the first region 202 to the distal end 224 of the third region 206.

[0088] In some cases, the first region 202 can be in the form of a stent 210 that includes an elongated tubular stent frame 212 defining a lumen, which can be similar in form and function to the proximal stent 20 described above. The stent 210 can be completely, substantially, or partially covered with a polymer covering, such as a coating (not explicitly shown). The covering can be located on the inner surface and / or outer surface of the stent frame 212 as desired. When a polymer covering is provided in this way, tissue growth and / or food impaction can be reduced or eliminated. The stent 210 can include regions of different diameters. For example, the stent 210 can include a flared (e.g., enlarged relative to other portions of the stent 210) proximal region 214 that tapers radially inwardly to a distal region 216 in the distal direction. Although not explicitly shown, if desired, the stent 210 can include a region of constant diameter or increased diameter (e.g., increasing in the distal direction). The stent frame 212 can expand between a radially contracted delivery configuration and a radially expanded deployment configuration. The expanded configuration may secure the implant 200 at a desired location within the body lumen.

[0089] In some cases, the third region 206 can be in the form of a stent 218, which includes an elongated tubular stent framework 220 defining a lumen, and the form and function of the stent 218 are similar to the distal stent 28 described above. The stent 218 can be completely, substantially or partially covered with a polymer covering, such as a coating (not explicitly shown). As desired, the covering can be provided on the inner surface and / or outer surface of the stent framework 220. When the polymer covering is provided in this way, tissue ingrowth and / or food impaction can be reduced or eliminated. The stent 218 can have a uniform outer diameter from its proximal region 222 to its distal region 224. In some cases, the distal region 224 may include a flared region 226 (e.g., an enlarged diameter or having an enlarged diameter relative to other portions of the stent 218). In some embodiments, the flared region 226 may include a transition region 228, which may be abrupt or stepped or flared or inclined, as desired, to provide a relatively constant expansion of its diameter. In other embodiments, the flared region can be tilted or flared (e.g., continuously changing outer diameter) along its entire length. The stent framework 220 can expand between a radially contracted delivery structure and a radially expanded deployment structure. The deployment structure can fix the implant 200 in the desired position in the body cavity. Although not clearly shown, in some embodiments, the distal support 218 can extend distally to the far end of the implant 200.

[0090] In some cases, the second portion 204 can be in the form of a flexible sleeve 230. The sleeve 230 can extend between the distal end of the proximal stent 210 and the proximal end of the distal stent 218. For example, the sleeve 230 can be connected, attached or fixed to the distal region 216 of the first stent or proximal stent 210 adjacent to the proximal region 232 of the sleeve 230. The sleeve 230 can also be connected, attached or fixed adjacent or distal to the proximal region 222 of the second stent or distal stent 218, which is adjacent to the distal region 234 of the sleeve 230. In some cases, the sleeve 230 may overlap a portion or all of the proximal stent 210 and / or a portion of the distal stent 218. In other words, the sleeve 230 can extend from the proximal region 214 of the proximal stent 210 to the distal region 224 of the distal stent 218, so that the implant 200 is completely covered. Alternatively, and / or additionally, one or both of the proximal support 210 and the distal support 218 can be covered with a material or structure different from the sleeve 230 to provide a partially covered implant 200. The sleeve 230 can be fixed to one or both of the supports 210, 218 by adhesive or other methods known in the art (including but not limited to thermal methods, mechanical methods, etc.).

[0091] The sleeve 230 can have an elongated tubular shape defining a cavity, and its form or function can be similar to the sleeves 36, 42 described above. The cavities of the stents 210, 218 and the flexible sleeve 230 can be fluidly connected to form the cavity 208 of the implant 200. As desired, it is contemplated that one or more regions 202, 204, 206 of the implant 200 can include more than one cavity. The sleeve 230 can be a thin flexible membrane that is easily self-contracting. However, in some cases, the sleeve 230 can provide radial support.

[0092] In an illustrative example, the size of the implant 200 can be set to be positioned in the gastric outlet, extending through the pylorus and into the duodenum to treat, for example, gastric outlet obstruction. In such an example, the size of the proximal stent 210 can be set to prevent the implant 200 from migrating distally through the gastric outlet. For example, the proximal region 214 of the proximal stent 210 can have an outer diameter 236 in the range of about 25 millimeters (mm) to about 50 mm. It is conceivable that the shape of the proximal stent 210 can be formed to match or roughly conform to the shape of the gastric outlet. The sleeve 230 can be configured to extend through the pylorus and can have a length 238 in the range of about 6 mm to about 15 mm. The size of the distal stent 218 can be set to be positioned in the duodenal bulb and the duodenum, respectively, and can have an outer diameter 240 in the range of about 15 mm to about 25 mm. The distal stent 218 can have a length 242 in the range of about 60 mm to about 200 mm. This is just an example. It is contemplated that the sleeve 230 may be positioned across other valves or sphincter regions, with the proximal and / or distal stents 210, 218 sized and shaped for the adjacent anatomical structures.

[0093] Once implanted in the patient, the stents 210, 218 can apply radial external forces to help fix the implant 200 to the body cavity. The implant 200 can be positioned in the esophagus, gastroesophageal junction (GEJ) area, or at or near the pylorus, and the sleeve 214 extends through the stomach or other parts of the gastrointestinal system. In one example, the implant 200 can be positioned so that the proximal stent 210 is positioned at the stomach outlet, and the sleeve 230 bridges the pylorus. The flared structure of the proximal stent 210 can use the stomach to anchor the implant 200 and serve as an anti-migration mechanism for the implant 200. For example, the large outer diameter 236 of the proximal end 214 of the proximal stent 210 can be engaged with the stomach outlet to prevent or limit the movement of the implant 200. The distal stent 218 can be placed in the duodenal bulb and can extend into the duodenum. The sleeve 230 can be connected to the proximal stent 210 and the distal stent 218 at the same time so that the relative position of each part is fixed.

[0094] In some cases, the function of the pyloric valve may not be affected or degraded by the disease state causing the gastric outlet obstruction. In this case, it may be necessary to open the obstruction while still allowing normal function of the pyloric valve. In other words, the sleeve 230 and therefore the length of the intermediate region 204 between the proximal stent 210 and the distal stent 218 can be unaffected by any structure configured to apply radial external forces to the surrounding tissue. This can allow the pyloric valve to function (e.g., open and close) in a natural manner. The distal stent 218 can be positioned near the gastric outlet obstruction. The stent frame 220 of the distal stent 218 can be configured to have sufficient radial force (e.g., apply sufficient radial external force) to open the obstruction caused by the disease state.

[0095] Figure 5 A side view of another exemplary implant 250 including multiple regions is shown, and the implant 250 includes a first region 252, a second region 254, and a third region 256. The exemplary implant 250 can be similar to the above-mentioned implant 10 in form and function. Although the exemplary implant 250 is shown and described as having three regions 252, 254, 256, it is conceivable that the implant 250 can include any desired number of regions, such as but not limited to one, two, three, four or more. Further, regions 252, 254, 256 can be any combination of desired structures and materials. In some cases, the implant 250 can include features (e.g., anti-migration flaring, fixing nails, sutures, etc.) that prevent the implant 10 from being displaced and / or migrated to the distal side / to the proximal side once the implant 250 is positioned and expanded in the body cavity. The implant 250 can include a cavity 258 extending from the proximal end 264 of the first region 252 to the distal end 224 of the third region 256.

[0096] In some cases, the first region 252 can be in the form of a stent 260, which includes an elongated tubular stent frame 262 defining a lumen, and the form and function of the stent 260 are similar to the proximal stent 20 described above. The stent 260 can be completely, substantially or partially covered with a polymer covering, such as a coating (not explicitly shown). As required, the covering can be provided on the inner surface and / or outer surface of the stent frame 262. When the polymer covering is provided in this way, tissue ingrowth and / or food impaction can be reduced or eliminated. The stent 260 may include regions of different diameters. For example, the stent 260 may include a flared (e.g., enlarged relative to other parts of the stent 260) proximal region 264 that tapers radially inwardly to a distal region 266 in the distal direction. Although not explicitly shown, if desired, the stent 260 may include a region of constant diameter or increased diameter (e.g., increased in the distal direction). The stent frame 262 can expand between a radially contracted delivery configuration and a radially expanded deployment configuration. The expanded configuration may secure the implant 250 at a desired location within the body lumen.

[0097] In some cases, the third region 256 can be in the form of a stent 268, which includes an elongated tubular stent frame 270 defining a lumen, and the form and function of the stent 268 are similar to the distal stent 28 described above. In some embodiments, the distal stent frame 270 can be formed using a different technology from the proximal stent frame 262. For example, the distal stent frame 270 can be knitted, while the proximal stent frame 262 can be braided. This is just one example. Other stent frame combinations can be used as needed. The stent 268 can be completely, substantially or partially covered with a polymer covering, such as a coating (not explicitly shown). As needed, the covering can be provided on the inner surface and / or outer surface of the stent frame 270. When the polymer covering is provided in this way, tissue ingrowth and / or food impaction can be reduced or eliminated. The stent 268 can have a uniform outer diameter from its proximal region 272 to its distal region 274. However, if desired, the stent 268 can include regions of different diameters. The stent frame 270 can expand between a radially contracted delivery configuration and a radially expanded deployment configuration. The expanded configuration can secure the implant 250 at a desired location in the body lumen. Although not explicitly shown, in some embodiments, the distal stent 268 can extend distally to the distal end of the implant 250.

[0098] In some cases, the second portion 254 can be in the form of a flexible sleeve 276. The sleeve 276 can extend between the distal end of the proximal stent 260 and the proximal end of the distal stent 268. For example, the sleeve 276 can be connected, attached or fixed to the distal region 266 of the first stent or proximal stent 260 adjacent to the proximal region 278 of the sleeve 276. The sleeve 276 can also be connected, attached or fixed adjacent or distal to the proximal region 222 of the second stent or distal stent 268, which is adjacent to the distal region 280 of the sleeve 276. In other words, the sleeve 276 can extend from the proximal region 264 of the proximal stent 260 to the distal region 224 of the distal stent 268 so that the implant 250 is not completely covered. Alternatively, and / or additionally, one or both of the proximal and distal stents 260, 268 may be covered with a material or structure different from that of the sleeve 276 to provide a partially covered implant 250. The sleeve 276 may be fixed to one or both of the stents 260, 268 by adhesive or other methods known in the art (including but not limited to thermal methods, mechanical methods, etc.).

[0099] The sleeve 276 can have an elongated tubular shape defining a cavity, and its form or function can be similar to the sleeves 36, 42 described above. The cavities of the stents 260, 268 and the flexible sleeve 276 can be fluidly connected to form the cavity 258 of the implant 250. As desired, it is contemplated that one or more regions 252, 254, 256 of the implant 250 can include more than one cavity. The sleeve 276 can be a thin flexible membrane that easily collapses on its own. However, in some cases, the sleeve 276 can provide radial support.

[0100] In one example, the size of the implant 250 can be set to be positioned in the gastric outlet, extending through the pylorus and into the duodenum to treat, for example, gastric outlet obstruction. In such an example, the size of the proximal stent 260 can be set to prevent the implant 250 from migrating distally through the gastric outlet. For example, the proximal region 264 of the proximal stent 260 can have an outer diameter 282 in the range of about 25 millimeters (mm) to about 50 millimeters. It is conceivable that the shape of the proximal stent 260 can be formed to match or roughly conform to the shape of the gastric outlet. The sleeve 276 can be configured to pass through the pylorus and can have a length 284 in the range of about 6 mm to about 15 mm. The size of the distal stent 268 can be set to be positioned in the duodenal bulb and the duodenum, respectively, and can have an outer diameter 286 in the range of about 15 mm to about 25 mm. The distal stent 268 can have a length 288 in the range of about 60 mm to about 250 mm. This is just an example. It is contemplated that the sleeve 276 may be positioned across other valves or sphincter regions, with the proximal and / or distal stents 260, 268 sized and shaped for the adjacent anatomical structures.

[0101] Once implanted in the patient, the stents 260, 268 can apply radial external forces to help fix the implant 250 to the body cavity. The implant 250 can be positioned in the esophagus, gastroesophageal junction (GEJ) area, or at or near the pylorus, and the sleeve 264 extends through the stomach or other parts of the gastrointestinal system. In one example, the implant 250 can be positioned so that the proximal stent 260 is positioned at the stomach outlet, and the sleeve 276 bridges the pylorus. The flared structure of the proximal stent 260 can use the stomach to anchor the implant 250 and serve as an anti-migration mechanism for the implant 250. For example, the large outer diameter 282 of the proximal end 264 of the proximal stent 260 can be engaged with the stomach outlet to prevent or limit the movement of the implant 250. The distal stent 268 can be placed in the duodenal bulb and can extend into the duodenum. The sleeve 276 can be connected to the proximal stent 260 and the distal stent 268 at the same time, so that the relative position of each part is fixed.

[0102] In some cases, the function of the pyloric valve may not be affected or degraded by the disease state causing the gastric outlet obstruction. In this case, it may be necessary to open the obstruction while still allowing the normal function of the pyloric valve. In other words, the sleeve 276 and therefore the length of the intermediate region 254 between the proximal stent 260 and the distal stent 268 can be unaffected by any structure configured to apply radial external forces to the surrounding tissue. This can allow the pyloric valve to function (e.g., open and close) in a natural manner. The distal stent 268 can be positioned near the gastric outlet obstruction. The stent frame 270 of the distal stent 268 can be configured to have sufficient radial force (e.g., apply sufficient radial external force) to open the obstruction caused by the disease state.

[0103] Figure 6 Shows Figure 1 A side view of an exemplary implant 10 including a retrieval suture 60. Some implants, such as but not limited to Figure 6 The implant 10 shown in the figure may be designed or intended to be removable or repositionable. In some cases, sutures, such as but not limited to the sutures 60 shown in the figure, may be used to shrink a portion of the implant (in some cases, the sutures may be interwoven through the support frame adjacent to the proximal end of the implant) to reduce the profile of the implant. As described above, the implant 10 may be positioned through a valve position (e.g., a pyloric valve) so that the proximal stent 20 is close to the valve and the distal stent 28 is away from the valve. Since the stent frame 22 of the proximal stent 20 is not directly connected to the stent frame 30 of the distal stent 28, the sutures interwoven through the proximal region 24 of the proximal stent 20 may not necessarily reduce the profile of the proximal stent 20 and the distal stent 28. It is conceivable that in order to remove or reposition the implant 10, it may be necessary to reduce the profile of the proximal stent 20 and the distal stent 28 to move the implant 10. For example, the distal stent 28 may have a larger expansion diameter than the pyloric valve (or other natural valve) to prevent or reduce proximal migration. Thus, in order to move the implant 10, it may be necessary to reduce the profile of the distal stent 28 from its deployed configuration.

[0104] In order to shrink both the proximal stent 20 and the distal stent 28, the suture 60 may include a plurality of components or regions, each of which is configured to perform a function. The first region of the suture 60 may be a retrieval suture loop 62, which may be configured to be grasped by forceps or another tool during a clinical procedure to remove the stent or reposition the stent. The retrieval suture loop 62 may extend proximally from the proximal region 24 of the proximal stent 20 so that the retrieval suture loop 62 is easy to grasp and pull in the proximal direction. However, this is not required. In some cases, it may be necessary to position the retrieval suture loop 62 near the distal stent 28. It is conceivable that the suture 60 may be arranged in many different modes so that the various parts of the proximal stent 20 and / or the distal stent 28 shrink in the desired order. For example, in some cases, it may be necessary to shrink the proximal region 32 of the distal stent 28 before shrinking the proximal stent 20.

[0105] The second region of the suture 60 may include a first suture loop 64 interwoven with the proximal region 24 of the proximal stent 20. The first suture loop 64 may extend around the entire circumference of the proximal region 24 of the proximal stent 20. The first suture loop 64 may be configured to reduce the profile of the proximal stent 20 by its deployed configuration. The third region of the suture 60 may include a second suture loop 66 interwoven in the proximal region 32 of the distal stent 28. The second suture loop 66 may extend around the entire circumference of the proximal region 32 of the distal stent 28. The second suture loop 66 may be configured to reduce the profile of the distal stent 28 by its deployed configuration. The fourth region of the suture 60 may include a connecting suture portion 68 extending and coupled between the first suture loop 64 and the second suture loop 66. The connecting suture portion 68 can be configured to couple the first suture loop 64 and the second suture loop 66, so that the actuation of the retrieval suture loop 62 is converted to both the first suture loop 64 and the second suture loop 66. It should be noted that in some cases, the suture 60 may not include a portion extending proximally from the first suture loop 64, such as the retrieval suture loop 62, so that the surgeon can directly grasp the first suture loop 64 to initiate the retrieval of the implant 10.

[0106] Suture 60 can be formed by the material length with first end 70 and second end 72. As required, this material length can be a long continuous unit structure or a plurality of structures are connected together. In order to assemble suture 60 with implant 10, first end 70 can be interwoven by the support frame 22 of the proximal region 24 of adjacent proximal support 20, until it extends around the circumference of proximal support 20 or substantially all circumferences. In some cases, suture 60 can be tied, knotted or otherwise fixed to itself at the junction of the circumferential portion of the first suture ring 64 and the connecting suture portion 68. Then, the first end 70 of suture 60 can be advanced to the distal side by proximal support 20 and proximal sleeve 36, until the proximal region 32 of distal support 28 is reached, thereby forming the connecting suture portion 68. It is contemplated that the connecting suture portion 68 may extend along the outer surface of the proximal stent 20 and the proximal sleeve 36 or along the inner surface (e.g., within the lumen 48) of the proximal stent 20 and the proximal sleeve 36, as desired. The first end 70 of the suture 60 may then be interwoven with the stent frame 30 adjacent the proximal region 32 of the distal stent 28 until extending around the circumference or substantially the entire circumference of the distal stent 28. The first end 70 of the suture 60 may then be knotted, tied, or otherwise secured to itself or the distal stent 28. The second end 72 of the suture 60 may be looped or knotted to form the retrieval suture loop 62.

[0107] To collapse the implant 10, the retrieval suture loop 62 or the first suture loop 64 without the retrieval suture loop 62 can be pulled up or otherwise actuated in the proximal direction. When the retrieval suture loop 62 or the first suture loop 64 without the retrieval suture loop 62 is pulled in the proximal direction, the first suture loop 64 begins to constrain or reduce the diameter of the proximal stent 20, such as Figure 7, which shows a side view of an exemplary implant 10 during actuation of the suture 60. It is contemplated that the length of the connecting suture portion 68 can be predetermined and selected based on the difference in diameter between the proximal region 24 of the proximal stent and the proximal region 32 of the distal stent 28 and the distance between the proximal region 24 of the first proximal stent 20 and the proximal region 32 of the distal stent 28. The length of the connecting suture portion 68 can be greater than the distance between the first suture loop 64 and the second suture loop 66 in the deployed, expanded configuration, leaving the connecting suture portion 68 slack. Thus, the length of the connecting suture portion 68 can be selected so that before tightening and tensioning the connecting suture portion 68, the first suture loop 64 is pulled to constrain the proximal region 24 of the proximal stent 20. Thereafter, further pulling on the retrieval suture loop 62, or pulling on the first suture loop 64 without the retrieval suture loop 62, causes the connecting suture portion 68 to apply tension to the second suture loop 66 to begin constraining the distal stent 28. For example, the length may be selected such that when the diameter of the proximal region 24 of the proximal stent 20 is locally constrained or reduced by a first amount, the second suture loop 66 begins to constrain or reduce the diameter of the distal stent 28 adjacent its proximal end 32. The length may be selected such that when the diameter of the proximal region 24 of the proximal stent 20 is constrained or reduced to approximately the same diameter as the distal region 32 of the distal stent, the second suture loop 66 begins to constrain the reduced diameter of the distal stent 28 adjacent its proximal end 32. In other words, the connecting suture portion 68 may include some slack or additional length to prevent proximal actuation of the retrieval suture loop 62 from actuating the second suture loop 66 until after the first suture loop 64 is at least partially constrained. Once the proximal region 24 of the proximal stent 20 has been locally constrained (e.g., to approximately the same diameter as the proximal region 32 of the distal stent 28), continued proximal actuation of the retrieval suture loop 62 will cause the proximal stent 20 and the distal stent 28 to simultaneously reduce in diameter or constrain at approximately the same rate, such as Figure 8 , which shows a side view of an exemplary implant 10 in a fully constrained configuration. This allows for stable and easy repositioning or removal. However, in some embodiments, the length of the connecting suture portion 68 can be selected so that the proximal region 24, 32 of the proximal and distal stents 20, 28 is configured to contract and reduce the profile at about the same time.

[0108] Fig. 9 Shows Figure 110, including another retrieval suture 80. In order to retract the proximal stent 20 and the distal stent 28, the suture 80 may include multiple components or regions, each of which is configured to perform a function. The first region of the suture 80 may be a retrieval suture loop 82, which may be configured to be grasped by forceps or another tool during a clinical procedure to remove the stent or reposition the stent. The second region of the suture 80 may include a first suture loop 84, which is interwoven within the distal region 34 of the distal stent 28. The first suture loop 84 may be configured to reduce the profile of the distal stent 28 by its deployment structure. The third region of the suture 80 may include a second suture loop 86, which is interwoven within the distal region 26 of the proximal stent 20. The second suture loop 86 may be configured to reduce the profile of the proximal stent 20 by its deployment structure. The fourth region of the suture 80 may include a connecting suture portion 88 extending and coupled between the first suture loop 84 and the second suture loop 86. The connecting suture portion 88 may be configured to couple the first suture loop 84 and the second suture loop 86 such that actuation of the retrieval suture loop 82 translates to both the first suture loop 84 and the second suture loop 86 .

[0109] Suture 80 can be formed by the material length with first end 90 and second end 72. As required, this material length can be a long continuous unit structure or a plurality of structures are linked together. In order to assemble suture 80 with implant 10, first end 90 can be interwoven by the stent framework 30 of the distal region 34 of adjacent distal support 28, until it extends around the circumference of distal support 28 or substantially all circumferences. In some cases, suture 80 can be tied, knotted or otherwise fixed to itself at the junction of the circumference portion of the first suture ring 84 and the connection suture portion 88. Then, the first end 90 of suture 80 can be advanced to the distal side by distal support 28 and proximal sleeve 36, until the distal region 26 of the proximal support 20 is reached, thereby forming the connection suture portion 88. It is contemplated that the connecting suture portion 88 may extend along the outer surface of the distal stent 28 and the proximal sleeve 36 or along the inner surface (e.g., within the lumen 48) of the distal stent 28 and the proximal sleeve 36, as desired. The first end 90 of the suture 80 may then be interwoven with the stent frame 22 adjacent the distal region 26 of the proximal stent 20 until extending around the circumference or substantially the entire circumference of the proximal stent 20. The first end 90 of the suture 80 may then be knotted, tied, or otherwise secured to itself or the proximal stent 20. The second end 92 of the suture 80 may be looped or knotted to form the retrieval suture loop 82.

[0110] To collapse the implant 10, the retrieval suture loop 82 may be pushed or otherwise actuated in the distal direction. It is contemplated that the device may be advanced through the lumen 48 to exert the distal force required to actuate the retrieval suture loop 82 in the distal direction. As the retrieval suture loop 82 is pushed in the distal direction, the first suture loop 84 begins to constrain or reduce the diameter of the distal stent 28, as shown in FIG. Fig.10 , which shows a side view of an exemplary implant 10 during actuation of the suture 80. It is contemplated that the length of the connecting suture portion 88 can be predetermined and selected based on the difference in diameter between the distal region 34 of the distal stent 28 and the distal region 26 of the proximal stent 20 and the distance between the distal region 34 of the distal stent 28 and the distal region 26 of the proximal stent 20. The length of the connecting suture portion 88 can be greater than the distance between the first suture loop 84 and the second suture loop 86 in the deployed, expanded configuration, leaving the connecting suture portion 88 slack. Therefore, the length of the connecting suture portion 88 can be selected so that before tightening and tensioning the connecting suture portion 88, the first suture loop 84 is pulled to constrain the distal region 34 of the distal stent 28. Thereafter, the retrieval suture loop 82 is further pulled so that the connecting suture portion 88 applies tension to the second suture loop 86 to begin constraining the proximal stent 20. For example, the length may be selected such that the second suture loop 86 begins to constrain or reduce the diameter of the proximal stent 20 adjacent its distal end 26 when the diameter of the distal region 34 of the distal stent 28 is locally constrained or reduced by a first amount. The length may be selected such that the distal stent 28 at least partially reduces in profile or diameter before reducing the diameter or profile of the distal region 26 of the proximal stent 20. In other words, the connecting suture portion 88 may include some slack or additional length to prevent distal actuation of the retrieval suture loop 82 from actuating the second suture loop 66 until after the first suture loop 84 is at least partially constrained. After any slack in the connecting suture portion 88 is consumed by distal actuation, continued distal actuation of the retrieval suture loop 82 will cause the proximal stent 20 and the distal stent 28 to simultaneously reduce in diameter or constrain at approximately the same rate, as shown in FIG. Fig.11 1, which shows a side view of an exemplary implant 10 in a fully constrained configuration. This can allow for stable and easy repositioning or removal in a distal direction. However, in some embodiments, the length of the connecting suture portion 88 can be selected so that the distal regions 26, 34 of the proximal and distal stents 20, 28 are configured to contract and reduce the profile at about the same time.

[0111] Although not explicitly shown, it is contemplated that the implant 10 may provide two or more suture lines or suture patterns, allowing the clinician to select which stent 20, 28 (and / or region of stent 20, 28) to collapse first. For example, the implant 10 may include Figure 6-8The suture structure 60 and Figure 9-11 Both suture structures 80 are shown in FIG.

[0112] Fig.12 A side view of another exemplary implant 300 is shown. Figure 302 shows a side view of another exemplary implant 300, such as but not limited to a stent. In some cases, the stent 300 can be formed by an elongated tubular stent framework 302. Although the stent 300 is described as being generally tubular, it is contemplated that the stent 300 can exhibit any cross-sectional shape desired. The stent 300 can have a first or proximal end 304, a second or distal end 306, and an intermediate region 308 located between the first end 304 and the second end 306. The stent 300 can include a cavity 310 extending from a first opening adjacent to the first end 304 to a second opening adjacent to the second end 306 to allow passage of food, fluids, etc.

[0113] The stent 300 can be expanded from a first radially contracted configuration (not explicitly shown) to a second radially expanded configuration. In some cases, the stent 300 can be deployed to a configuration between the contracted configuration and the fully deployed configuration. The stent 300 can be configured to extend through the stenosis and apply radially outward pressure to the stenosis in the cavity to open the cavity and allow food, fluids, air, etc. to pass through.

[0114] The stent framework 302 can have an interwoven structure made of a plurality of filaments. In some embodiments, the stent frameworks 22, 30 can be braided with one filament. In other embodiments, the stent framework 302 can be braided with several filaments, for example, in the stent manufactured and distributed by Boston Scientific Corp. and In another embodiment, the stent framework 302 may be knitted, such as ULTRAFLEX manufactured by Boston Scientific International, Inc. TM In yet another embodiment, the stent framework 302 may be of a knotted type, such as PRECISION COLONIC manufactured by Boston Scientific International, Inc. TM Stent. The stent frame 302 may be laser cut, such as the EPIC manufactured by Boston Scientific International, Inc. TM Bracket.

[0115] It is contemplated that stent 300 may be made of many different materials as desired, such as but not limited to metals, metal alloys, shape memory alloys, and / or polymers, so that stent 300 can expand to take shape when accurately positioned within the body. In some cases, the material may be selected so that stent 300 can also be relatively easily removed. For example, stent 300 may be formed of alloys, such as but not limited to Nitinol and Depending on the structural material selected, the stent 300 can be self-expanding (i.e., configured to automatically expand radially when unconstrained). In some embodiments, the stent 300 can be made using fibers, which can be composite fibers, for example, having a shell made of nitinol with a platinum core. It is further contemplated that the stent 300 can be formed from a polymer including, but not limited to, polyethylene terephthalate (PET). In some embodiments, the stent 300 can be self-expanding, while in other embodiments, the stent 300 can be expanded by an expansion device (e.g., but not limited to a balloon inserted into the lumen 310 of the stent 300). The term "self-expanding" as used herein refers to the tendency of the stent to return to a preset diameter when not constrained by an external biasing force (e.g., but not limited to a delivery catheter or sheath). The stent 300 can include a one-way valve, such as an elastomeric slit valve or a duckbill valve, positioned within its lumen 310 to prevent retrograde flow of fluid or other substances (such as gastrointestinal fluids).

[0116] In some cases, in the radially expanded configuration, the stent 300 may include a first end region 312 proximal to the proximal end 304 and a second end region 314 proximal to the second end 306. In some embodiments, the first end region 312 and the second end region 314 may include a retention feature or an anti-migration flared region having a diameter expanded relative to the middle portion 308 (not explicitly shown in the second end region 314). The anti-migration flared region, which may be positioned adjacent to the first end 304 and the second end 306 of the stent 300, may be configured to engage with the inner portion of the wall of the esophagus, stomach, or other body cavity. In some embodiments, the retention feature or flared region may have a larger diameter than the cylindrical middle region 308 of the stent 300 to prevent the stent 300 from migrating once placed in the esophagus, stomach, or other body cavity. It is conceivable that the transition from the cross-sectional area of ​​the middle region 308 to the retention feature or flared region may be gradual, inclined, or occur in an abrupt, stepped manner as desired. In other embodiments, the stent 300 may have a uniform diameter from the proximal end 304 to the distal end 306.

[0117] It is contemplated that stent 300 may be made of many different materials as desired, such as, but not limited to, metals, metal alloys, shape memory alloys, and / or polymers, to enable stent 300 to expand and take shape when accurately positioned within the body. In some cases, the material may be selected so that stent 300 may also be relatively easy to remove. For example, stent 300 may be formed of alloys, such as, but not limited to, nitinol and Depending on the structural material selected, the stent 300 may be self-expanding or require an external force to expand the stent 300. In some embodiments, a composite filament may be used to manufacture the stent 300, which may include, for example, a shell or cladding made of nitinol and a core formed of platinum or other radiopaque materials. It is further contemplated that the stent 300 may be formed of a polymer including, but not limited to, polyethylene terephthalate (PET). In some embodiments, the filaments of the stent 300, or portions thereof, may be bioabsorbable or biodegradable, while in other cases, the filaments of the stent 300, or portions thereof, may be biostable.

[0118] The implant 300 may be completely, substantially, or partially covered with a polymeric covering, such as a coating (not explicitly shown). As desired, the covering may be disposed on the inner and / or outer surfaces of the implant 300. When a polymeric covering is provided in this manner, tissue ingrowth and / or food impaction may be reduced or eliminated.

[0119] Implant 300 can also include retrieval suture 320.Suture 320 can include retrieval suture loop 322, which can be configured to be grabbed by forceps or other tools during clinical procedures to remove the support and or reposition the support.Suture 320 can be interlaced with the stent framework 302 at intervals along the length of implant 300 to form a plurality of suture loops 324a, 324b, 324c, 324d, 324e, 324f, 324g (collectively referred to as 324). Each of the suture loops 324 can extend completely around the circumference of the stent framework 302. It is conceivable that the suture loops 324 can be positioned at regular or uniform intervals over the entire length of the implant 300. However, in other embodiments, the suture loops 324 can be positioned at eccentric or uneven intervals along the length of the implant 300 as needed. Adjacent suture loops 324 can be connected to the longitudinal length of the suture 320 extending therebetween. For example, adjacent suture loops 324 can be connected to suture connecting links 326a, 326b, 326c, 326d, 326e, 326f (collectively referred to as 326) so that actuation of retrieving the suture loop 322 is converted into individual suture loops 324 through the suture connecting links 326 extending longitudinally between each consecutive suture loop 324 along the length of the implant 300.

[0120] To collapse the implant 300, the retrieval suture loop 322 or the first suture loop 134a without the retrieval suture loop 322 can be pulled or otherwise actuated in the proximal direction. It is contemplated that the direction of actuation required to actuate the suture loop 320 (e.g., proximal or distal) can depend on the direction of interweaving of the suture loop 320 with the stent frame 302. When the retrieval suture loop 322 or the first suture loop 134a without the retrieval suture loop 322 is actuated, the suture loop 324 begins to constrain or reduce the diameter of the implant 300, as shown in FIG. Fig.13 , which shows a side view of an exemplary implant 300 during actuation of the suture 320. In some cases, the connecting links 326 can have a length such that the suture loops 324 simultaneously (or approximately simultaneously) constrain the implant 300 along their lengths. However, this is not required. In some cases, the connecting links 326 can have a length such that the suture loops 324 are actuated sequentially. For example, the next sequential suture loop 324 may not be actuated until the slack is removed from the preceding longitudinally extending suture connecting link 326 and the suture connecting link 326 is tightened to apply force to the next suture loop 324. Continued actuation of the retrieving suture loops 322 can cause the diameter of the implant 300 to further decrease, as shown. Fig.14 , which shows a side view of an exemplary implant 300 in a fully constrained configuration. It is contemplated that simultaneously constraining the suture loop 324 can reduce the delay time between actuation of the retrieval suture loop 322 and movement of the implant 300 during repositioning or removal. This can allow the implant 300 to be repositioned and / or removed with minimal impact on the vessel wall.

[0121] The material of various assemblies and various elements thereof that can be used for implant 10,100,150,200,250,300 (and variant, system or assembly disclosed herein) can include those materials that are usually relevant to medical equipment.For simplicity, discussion below is with reference to implant 10,100,150,200,250,300 (and variant, system or assembly disclosed herein).But this is not intended to limit equipment and method described herein, because discussion can be applicable to other element, member, assembly or equipment disclosed herein.

[0122] The implant 10, 100, 150, 200, 250, 300 can be made of metal, metal alloy, polymer (some examples are disclosed below), metal polymer composite, ceramic, combinations thereof, etc. or other suitable materials. Some examples of suitable metals and metal alloys include stainless steel, such as 304V, 304L and 316LV stainless steel; mild steel; nickel titanium alloys, such as linear elastic and / or superelastic nickel titanium alloys; other nickel alloys, such as nickel chromium molybdenum alloys (e.g., UNS: N06625 such as 625、UNS:N06022 such as UNS:N10276 other alloys, etc.), nickel-copper alloys (such as UNS: N04400, etc. 400, 400, 400, etc.), nickel-cobalt-chromium-molybdenum alloys (such as UNS: R30035, etc. etc.), nickel-molybdenum alloys (e.g. UNS: N10665 such as ALLOY ), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, etc.; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g. UNS: R30003 such as etc.); platinum-rich stainless steel; titanium; combinations thereof; etc.; or any other suitable material.

[0123] As mentioned in passing herein, within the family of commercially available nickel-titanium alloys or Nitinols, there is a category referred to as "linear elastic" or "non-superelastic" that, while chemically similar to conventional shape memory and superelastic varieties, may exhibit unique and useful mechanical properties. Linear elastic and / or non-superelastic Nitinol is distinguished from superelastic Nitinol in that linear elastic and / or non-superelastic Nitinol does not exhibit a substantial "superelastic plateau" or "landmark region" in its stress / strain curve. Instead, in linear elastic and / or non-superelastic Nitinol, as recoverable strain increases, stress continues to increase in a substantially linear or somewhat, but not necessarily completely, linear relationship until plastic deformation begins or at least in a relationship that is more linear than the superelastic plateau and / or landmark region seen with superelastic Nitinol. Therefore, for the purposes of the present invention, linear elastic and / or non-superelastic Nitinol may also be referred to as "substantially" linear elastic and / or non-superelastic Nitinol.

[0124] In some cases, linear elastic and / or non-superelastic Nitinol can also be distinguished from superelastic Nitinol, as linear elastic and / or non-superelastic Nitinol can withstand strains up to about 2-5% while remaining substantially elastic (e.g., before plastic deformation), whereas superelastic Nitinol can withstand strains up to about 8% before plastic deformation. Both of these materials can be distinguished from other linear elastic materials, such as stainless steel (which can also be distinguished based on its composition), which can only accept strains of about 0.2% to 0.44% before plastic deformation.

[0125] In some embodiments, the linear elastic and / or non-superelastic nickel-titanium alloy is an alloy that does not exhibit any martensite / austenite phase transformation that can be detected by differential scanning calorimetry (DSC) and dynamic metal thermal analysis (DMTA) analysis over a wide temperature range. For example, in some embodiments, the martensite / austenite phase transformation in the linear elastic and / or non-superelastic nickel-titanium alloy may not be detected by DSC and DMTA analysis within a range of about -60 degrees Celsius (°C) to about 120°C. Therefore, over this very wide temperature range, the mechanical bending properties of this material are generally inert to the effects of temperature. In some embodiments, the mechanical bending properties of the linear elastic and / or non-superelastic nickel-titanium alloy mechanical properties at ambient or room temperature are substantially the same as those at body temperature, for example, because they do not show a superelastic platform and / or signature region. In other words, over a wide temperature range, the linear elastic and / or non-superelastic nickel-titanium alloy maintains its linear elastic and / or non-superelastic properties and / or performance.

[0126] In some embodiments, the linear elastic and / or non-superelastic nickel-titanium alloy can be in the range of about 50% to about 60% by weight nickel, with the remainder being substantially titanium. In some embodiments, the nickel content of the composition is about 54% to about 57% by weight nickel. An example of a suitable nickel-titanium alloy is the FHP-NT alloy available from Furukawa Techno Material Co., Kanagawa, Japan. Some examples of nickel-titanium alloys are disclosed in U.S. Patent Nos. 5,238,004 and 6,508,803, which are incorporated herein by reference. Other suitable materials may include ULTANIUM TM (available from Neo-Metrics) and GUM METAL TM (Available from Toyota.) In some other embodiments, superelastic alloys, such as superelastic Nitinol, may be used to achieve the desired properties.

[0127] In at least some embodiments, part or all of the implant 10, 100, 150, 200, 250, 300 may also be doped with, made of, or otherwise include a radiopaque material. Radiopaque materials are generally understood to be materials that are opaque to radio frequency (RF) energy in the wavelength range spanning X-rays to gamma rays (thickness <0.005"). These materials are able to produce a relatively dark image on a fluoroscopic screen relative to the light image of non-radiopaque materials such as tissue. This relatively bright image helps the user of the implant 10, 100, 150, 200, 250, 300 to determine its position. Some examples of radiopaque materials may include, but are not limited to, gold, platinum, palladium, tantalum, tungsten alloys, polymer materials loaded with radiopaque fillers, etc. In addition, other radiopaque marker bands and / or coils may also be incorporated into the design of the implant 10, 100, 150, 200, 250, 300 to achieve the same effect.

[0128] In some embodiments, a degree of magnetic resonance imaging (MRI) compatibility is imparted to the implant 10, 100, 150, 200, 250, 300. For example, the implant 10, 100, 150, 200, 250, 300, or portions thereof, may be made of a material that does not substantially distort the image and produce a substantial amount of artifacts (e.g., gaps in the image). For example, some ferromagnetic materials may not be suitable because they may produce artifacts in MRI images. The implant 10, 100, 150, 200, 250, 300, or portions thereof, may also be made of a material that can be imaged by an MRI machine. Some materials that exhibit these properties include, for example, tungsten, cobalt-chromium-molybdenum alloys (e.g., UNS: R30003, such as etc.), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035, e.g. etc.), nickel-titanium alloy, etc.

[0129] Examples of some polymers suitable for use in the implants 10, 100, 150, 200, 250, 300 may include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, available from DuPont, for example). ), polyether block esters, polyurethanes (e.g., polyurethane 85A), polypropylene (PP), polyvinyl chloride (PVC), polyether esters (e.g., available from DSM Engineering Plastics) ), ether- or ester-based copolymers (e.g., butylene / poly(alkylene ether) phthalates and / or other polyester elastomers, such as those available from DuPont ), polyamides (e.g., available from Bayer Or can be purchased from Elf Atochem ), elastomeric polyamides, block polyamide / ethers, polyether block amides (PEBA, for example, can be ), ethylene vinyl acetate copolymer (EVA), silicone resin, polyethylene (PE), Marex high-density polyethylene, Marex low-density polyethylene, linear low-density polyethylene (e.g. ), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polyterephthalamide (e.g., ), polysulfone, nylon, nylon 12 (such as purchased from EMS American Grilon ), perfluoropropyl vinyl ether (PFA), ethylene vinyl alcohol, polyolefins, polystyrene, epoxy resins, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (e.g., SIBS and / or SIBS 50A), polycarbonate, ionomers, biocompatible polymers, other suitable materials or their mixtures, combinations, copolymers, polymer / metal composites, etc.

[0130] Those skilled in the art will appreciate that the different embodiments of the implants described herein, their modes of operation, etc., merely represent the operating environment of the present invention. Therefore, various alternative shapes of cooperative components may also be used as substitutes, so that the support is engaged, turned and positioned at the desired target site, therefore, without limiting the scope of the present disclosure. Further, the implant of the present invention may be fully telescopic, extended and retractable, allowing it to be flexibly deployed. More specifically, the configuration described herein may also be applicable to other medical applications, and therefore, various other medical devices may be used in combination with the implant. These medical devices may include biopsy forceps, scissors, lithotripters, dilators, other cautery tools, etc.

[0131] Further, although implants are generally described with exemplary rigidity and flexible regions, various other configurations and arrangements may also be considered and envisioned. In addition, the operations, equipment and assemblies described herein may be equally applicable to other purposes, where the assembly may need to be positioned to avoid leakage or other processing needs. Therefore, embodiments of the present invention are applicable to medical and / or non-medical environments. Further, aspects of the above-described embodiments may be selectively collaboratively used or removed in practice without departing from the scope of the disclosed embodiments.

[0132] Those skilled in the art will recognize that the present invention may be embodied in many forms other than the specific embodiments described and contemplated herein. Therefore, departures may be made in form and detail without departing from the scope and spirit of the present invention as described in the following claims.

Claims

1. An implant, comprising: An elongated tubular member comprising: a first region defining a proximal end of the implant, the first region comprising a proximal stent framework; a second region defining a distal end of the implant, the second region including a distal stent framework having a length extending along a longitudinal axis of the elongated tubular member; and A retrieval suture having a distal region interwoven with the distal stent frame along the length of the distal stent frame and a proximal region interwoven with the proximal stent frame, the retrieval suture defining a first suture loop interwoven with the distal stent frame, a second suture loop interwoven with the proximal stent frame, and a longitudinal portion extending between and coupled to the first suture loop and the second suture loop, wherein distal actuation of the retrieval suture sequentially contracts the first suture loop and the second suture loop to sequentially contract the distal stent frame and the proximal stent frame, and after the diameter of the distal stent frame is at least partially reduced, further distal actuation of the retrieval suture contracts the proximal stent frame.

2. An implant as described in claim 1, wherein the longitudinal portion has a slack portion, and the slack portion is configured so that when the first suture ring is contracted to reduce the diameter of the distal stent frame, the second suture ring will not be actuated until the slack portion is tightened.

3. An implant as described in claim 1 or 2, wherein the first suture loop is interwoven within the distal region of the proximal stent framework.

4. The implant of claim 3, wherein the second suture loop is interwoven within the distal region of the distal stent framework.

5. The implant of claim 4, wherein the proximal stent framework has a flared proximal end that tapers radially inwardly toward a distal end of the proximal stent framework.

6. The implant of claim 5, wherein the outer diameter of the distal stent framework is smaller than the outer diameter of the flared proximal end of the proximal stent framework.

7. The implant of claim 5, wherein the flared proximal end of the proximal stent framework is not collapsed when the elongated tubular member is in the fully collapsed configuration.

8. The implant of claim 1, wherein the retrieval suture is a long continuous piece of material.

9. The implant of claim 1, wherein the first suture loop extends around the entire circumference of the distal stent framework and / or the second suture loop extends around the entire circumference of the proximal stent framework.

10. The implant of claim 1, wherein the length of the longitudinal portion is greater than the distance between the first suture loop and the second suture loop.

11. An implant, comprising: An elongated tubular stent framework comprising: a first end region proximal to the first end of the implant; a second end region proximal to the second end of the implant; A retrieval suture having a distal region interwoven with the distal stent frame along the length of the distal stent frame, and a proximal region interwoven with the proximal stent frame, the retrieval suture defining a first suture loop interwoven with the distal stent frame, a second suture loop interwoven with the proximal stent frame, and a longitudinal portion extending between and coupled to the first suture loop and the second suture loop, wherein distal actuation of the retrieval suture sequentially contracts the first suture loop and the second suture loop to sequentially contract the distal stent frame and the proximal stent frame such that distal actuation of the retrieval suture first reduces a diameter of the distal stent frame, and after the diameter of the distal stent frame is at least partially reduced, further distal actuation of the retrieval suture contracts the proximal stent frame.

12. The implant of claim 11, wherein the suture connecting links each have a length such that actuation of the retrieval suture sequentially contracts a plurality of suture loops along the length of the implant.

13. An implant as described in claim 12, wherein the suture connecting link is configured so that the next consecutive suture loop will not be actuated until the slack portion on the previous longitudinally extending suture connecting link is removed and the suture connecting link is tightened to apply force to the next consecutive suture loop.

14. The implant of any one of claims 11-13, wherein the first end region has a flared region having a larger diameter than the middle region.

15. The implant of any one of claims 11-13, wherein each of the plurality of suture loops extends around the entire circumference of the stent framework.

16. The implant of any one of claims 11-13, wherein the retrieval suture comprises a retrieval suture loop configured to be grasped by a tool to remove or reposition the stent.

17. An implant, comprising: An elongated tubular member, the elongated tubular member comprising: a first region defining a proximal end of the implant, the first region comprising a proximal stent framework; a second region defining a distal end of the implant, the second region including a distal stent framework having a length extending along a longitudinal axis of the elongated tubular member; and a retrieval suture having a proximal region interwoven with the proximal stent framework and a distal region interwoven with the distal stent framework along a length of the distal stent framework, the retrieval suture defining at least three spaced suture loops connected by at least two longitudinal portions, wherein proximal actuation of the retrieval suture contracts the proximal stent framework and the distal stent framework; wherein proximal actuation of the retrieval suture sequentially contracts spaced suture loops along the length of the distal stent framework, wherein the longitudinal portions each have a slack portion configured such that a first suture loop is contracted and an adjacent suture loop is not actuated until the slack portion is taken up from a preceding longitudinal portion.

18. The implant of claim 17, wherein each of said spaced suture loops extends around the entire circumference of said elongated tubular member.

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