Stent delivery device

Abstract

A stent delivery device for delivering a self-expanding stent, the stent delivery device comprising: an inner sheath including a proximal end and a distal end; a stent stop including a stop body and at least one protrusion, the stop body being circumferentially disposed on at least a portion of the inner sheath at the proximal end, the at least one protrusion extending radially outward from the stop body for releasably engaging a portion of the self-expanding stent; and an outer sheath slidably disposed on the inner sheath and the stent stop. The at least one protrusion includes a distal surface and a proximal surface, and the proximal surface includes a recess extending toward the distal surface into a body of the protrusion.

Description

[0001] Relevant application data

[0002] Pursuant to 35 s. 119 of the United States Code, this application is based on and claims priority to U.S. Provisional Application No. 63 / 129,996, filed December 23, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to a stent delivery device and system, and more particularly, to a stent delivery device and system in which a stent stop is arranged on an inner sheath for releasing and / or recapturing a self-expanding stent. Background Technology

[0004] In medicine, a stent is a metal or plastic tube inserted into the lumen of an anatomical blood vessel or catheter to keep the passage open, and stent placement is the procedure of placing a stent in a target area. Typically, a stent will have an unexpanded (reduced or closed) diameter for placement and an expanded (open) diameter after placement in the blood vessel or catheter. Some stents are self-expanding, some are mechanically expanded using radial outward forces within the stent, such as by the expansion of a balloon; some stents (known as hybrid stents) possess one or more characteristics common to both self-expanding and mechanically expandable stents.

[0005] Self-expanding stents are typically delivered to the desired body location via an inner sheath, in their unexpanded diameter state and covered by an outer sheath. Once in the desired body location, the outer sheath is pulled back to expose the stent, allowing it to expand and be implanted into the body cavity.

[0006] In traditional support conveying systems, especially those used for conveying self-expanding supports, the supports are typically constrained to an inner sleeve by an outer sleeve that acts as a retaining device. The supports can be deployed by retracting the outer sleeve from them. To prevent the supports from being pulled longitudinally as the outer sleeve retracts, many conveying systems provide one or more support stops, such as buffers or hubs, for the inner sleeve shaft.

[0007] However, it is known that in many cases, when the outer sheath is withdrawn from the stent (especially self-expanding stents made of shape memory materials), the stent may shift longitudinally relative to the inner sheath axis. This is because the stent tends to migrate or skip longitudinally relative to the stent placement area of ​​the inner sheath, resulting in inaccurate stent delivery and / or stent body deformation. Therefore, when the surgeon feels that the stent may be missing the desired delivery position during placement, a recapture operation is performed. In this recapture operation, the once-expanded stent is retracted and repositioned in the delivery system for position adjustment. Stent stops are typically used for recapture operations.

[0008] The stent stop in the stent delivery device and system should be configured to restrain the stent against the inner sleeve during recapture and not impede the stent's release from the delivery device via self-expansion when fully deployed. Conventional stent delivery devices and systems have drawbacks in combining these two conflicting functions. Therefore, it is desirable to provide a stent delivery device and system in which the stent stop can effectively combine the conflicting functions of restraining and releasing a self-expansion stent. Summary of the Invention

[0009] Therefore, this disclosure relates to a support delivery device and system that substantially eliminates one or more problems caused by the limitations and disadvantages of related support delivery devices and systems.

[0010] One object of this disclosure is to provide a stent delivery device for delivering a self-expanding stent. The device includes: an inner sheath including a proximal end and a distal end; a stent stop including a body and at least one protrusion, the body being circumferentially disposed on at least a portion of the inner sheath at the proximal end, and the at least one protrusion extending radially outward from the body for releasably engaging a portion of the self-expanding stent; and an outer sheath slidably disposed on the inner sheath and the stent stop. The at least one protrusion includes a distal surface and a proximal surface, and the proximal surface includes a recess extending toward the distal surface into the body of the protrusion.

[0011] Another object of this disclosure is to provide a stent delivery device for delivering a self-expanding stent, comprising: an inner sheath including a proximal end and a distal end; a stent stop including a body and at least one protrusion, the body being circumferentially disposed on at least a portion of the inner sheath at the proximal end, the at least one protrusion extending radially outward from the body for releasably engaging a portion of the self-expanding stent; and an outer sheath slidably disposed on the inner sheath and the stent stop. The at least one protrusion includes a distal surface, a proximal surface, and an upper surface formed between the distal surface and the proximal surface. The upper surface is configured to have a generally trapezoidal shape that narrows longitudinally toward the proximal surface of the inner sheath.

[0012] Additional features and advantages will be set forth in the following description, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the disclosed support delivery device and system will be realized and obtained through the written description, its technical solutions, and the structures particularly pointed out in the drawings. Attached Figure Description

[0013] The following detailed description of the preferred embodiments can be read in conjunction with the accompanying drawings, in which the same numbers represent the same elements, wherein:

[0014] Figure 1AThis is a schematic plan view of a support delivery system according to an exemplary embodiment. Figure 1B yes Figure 1A A plan view of the far end of the support conveying system.

[0015] Figure 2A This is a plan view of a bracket conveying device having an inner sheath and bracket stops arranged on the inner sheath, according to an exemplary embodiment. Figure 2B It is to arrange the support in Figure 2A A plan view of the support conveying device on the inner sheath.

[0016] Figure 3 This is a plan view illustrating a stent delivery device that partially deploys a stent within a body cavity according to an embodiment of the present invention.

[0017] Figure 4 This is according to an exemplary implementation. Figure 3 A three-dimensional schematic diagram of the support stop of the support conveying device.

[0018] Figure 5 This is a side view of a bracket stop according to an exemplary embodiment.

[0019] Figures 6A-6B This is a schematic diagram of an exemplary construction of the upper surface of the protrusion of a bracket stop according to an exemplary embodiment, shown in a plan view.

[0020] Figure 7 The illustration is based on an exemplary embodiment. Figure 6A Another schematic diagram of the structural configuration of the upper surface of the bracket stop.

[0021] Figures 8A-8C This is a schematic side view illustrating various embodiments of the proximal surface of the protrusion of the support stop according to various implementations and the recess extending into the body of the protrusion.

[0022] Figures 9A-9C This is a schematic diagram illustrating the structural relationship between the protruding proximal surface of the bracket stop, the recess, and the bracket according to various embodiments.

[0023] Figure 10A and Figure 10B This is a schematic diagram illustrating the structural configuration of the proximal surface of the protrusion and the recesses and supports extending into the body of the protrusion in different embodiments.

[0024] Figure 11 This is a schematic cross-sectional view illustrating the structure of a bracket stop according to an exemplary embodiment.

[0025] Figure 12This is a side view schematically illustrating the structural relationship between a support stop and a fully expanded support according to an exemplary embodiment.

[0026] Figures 13A-13D This is an example of a bracket stop according to an additional embodiment.

[0027] Figures 14A-14C This is a schematic diagram illustrating the structural deformation of the bracket stop according to an additional embodiment.

[0028] Figure 15A and Figure 15B It is a diagram and Figure 14B and Figure 14C A schematic diagram of the support structure in combination with various implementation methods. Detailed Implementation

[0029] In the following description, various exemplary embodiments of the support conveying device and system according to the present invention will be illustrated with reference to the accompanying drawings. In all the drawings, the thickness or dimensional ratios of the various constituent elements have been appropriately adjusted for clarity.

[0030] Figure 1A This is a schematic plan view of a support delivery system 100 according to an exemplary embodiment. Figure 1B yes Figure 1A A plan view of the far end of the support conveying system.

[0031] like Figure 1A As shown, the stent delivery system 100 is suitable for endovascular applications, including but not limited to biliary and vascular applications. In biliary applications, the stent delivery system 100 can be sized to fit within an endoscope (not shown) and be guided to the desired site within the biliary tract. In vascular applications, the stent delivery system 100 can be sized to fit within an introduction sheath (not shown) and / or an introduction catheter (not shown) to be guided to the desired vascular site.

[0032] The stent delivery system 100 includes an inner sheath 10 slidably disposed within an outer sheath 20. The outer sheath 20 includes a lumen (not visible) extending through the outer sheath 20 to slidably receive the inner sheath 10. The inner sheath 10 includes a guidewire lumen extending through a distal end of the inner sheath 10 to receive a guidewire GW. The guidewire GW can exit through a guidewire opening 22 in the outer sheath 20.

[0033] The stent delivery system 100 advances along the guidewire GW to deliver and deploy a self-expanding stent 30 within the body cavity. The guidewire GW can be any guidewire as known in the art. The guidewire GW is typically an elongated, relatively rigid but generally flexible cylindrical member. The guidewire GW can be made of any material, but is preferably made of metal, such as stainless steel, gold, platinum, and metal alloys such as cobalt-based alloys or titanium alloys, such as nickel-titanium shape memory alloys (i.e., nitinol), titanium-aluminum-vanadium alloys, and titanium-zirconium-niobium alloys. Furthermore, the guidewire GW can have constant rigidity or flexibility along its entire length, or it can have sections with different levels of rigidity and flexibility, such as a region of increased flexibility at the tip of the guidewire.

[0034] The guidewire GW may also include a coating, such as a lubricating or frictionless coating material, along a portion or the entire length of the guidewire GW. The guidewire may also have radiopaque portions, such as in the form of a radiopaque coating on a portion of the guidewire or a portion of the guidewire constructed from a radiopaque material.

[0035] like Figure 1A As shown, the stent delivery system 100 also includes a proximal handle 40 connected to the proximal end 16 of the inner sheath 10 and a distal handle 50 connected to the proximal end 26 of the outer sheath 20. The distal handle 50 can be longitudinally displaced relative to the proximal handle 40 to selectively expose or cover the stent 30. (Refer to...) Figure 1A The distal handle 50 has been longitudinally displaced relative to the proximal handle 40 in the distal direction, causing the outer sheath 20 to cover the bracket 30. (Refer to...) Figure 1B The distal handle 50 has been longitudinally displaced relative to the proximal handle 40 to retract the outer sheath 20 relative to the inner sheath 10, thereby exposing and unfolding the support 30.

[0036] The distal head 52 can be attached to the distal end of the distal interior of the inner sheath 10 to limit distal displacement of the outer sheath 20 when needed. For example, a radiopaque marking strip 51 can be located on the inner sheath 10 to facilitate placement of the stent 30 during intraluminal delivery.

[0037] Mark 51 may include any useful one or more radiopaque materials, including any metal or plastic that is radiopaque or can be impregnated with a radiopaque material. Useful radiopaque materials include, but are not limited to, gold, barium sulfate, ferrite particles, platinum, platinum-tungsten, palladium, platinum-iridium, rhodium, tantalum, or combinations thereof.

[0038] The stent 30 can be made of any suitable implantable material, including but not limited to nitinol, stainless steel, and other materials. Cobalt-based alloys, platinum, gold, titanium, tantalum, niobium, polymeric materials, and combinations thereof. Examples of useful and non-limiting polymeric scaffold materials include poly(L-lactide) (PLLA), poly(D,L-lactide) (PLA), poly(glycolic acid) (PGA), poly(L-lactide-co-D,L-lactide) (PLLA / PLA), poly(L-lactide-co-glycolic acid) (PLLA / PGA), poly(D,L-lactide-co-glycolic acid) (PLA / PGA), poly(glycolic acid-co-trimethylene carbonate) (PGAIPTMC), polydioxanone (PDS), polycaprolactone (PCL), polyhydroxybutyrate (PHBT), poly(phosphazene)poly(D,L-lactide-co-caprolactone) PLA / PCL, poly(glycolic acid-co-caprolactone) (PGAIPCL), poly(phosphate esters), etc.

[0039] Furthermore, the stent 30 or a portion thereof may have a composite construction. For example, the stent 30 may have an inner core made of tantalum, platinum, iridium, or a combination thereof, and an outer member or outer layer made of nitinol to provide a composite wire for improving radioactivity or visibility. Alternatively, the stent 30 may be made of nitinol.

[0040] Furthermore, the stent 30 can be treated with any known or useful bioactive agents or drugs, including but not limited to: antithrombotic agents (such as heparin, heparin derivatives, urokinase, and PPack (d-phenylalanine-proline-arginine-chloromethyl ketone); antiproliferative agents (such as enoxaparin, angiopeptidase, or monoclonal antibodies that can block smooth muscle cell proliferation, hirudin, and acetylsalicylic acid); anti-inflammatory agents (such as dexamethasone, prednisolone, corticosteroids, budesonide, estrogens, sulfasalazine, and mesalazine); antitumor / antiproliferative / antimiotic agents (such as paclitaxel, 5-fluorouracil, cisplatin, vincristine, epoch-forming alkaloids, epoch-forming alkaloids, endostatin, angiostatin, and thymidine kinase inhibitors); anesthetics (such as lidocaine, bupivacaine, and ropivacaine); and anticoagulants (such as D-...). Phe-Pro-Arg chloromethyl ketone, compounds containing ROD peptides, heparin, antithrombin compounds, platelet receptor antagonists, antithrombin antibodies, antiplatelet receptor antibodies, aspirin, prostaglandin inhibitors, platelet inhibitors, and tick antiplatelet peptides; angiogenesis promoters (such as growth factor inhibitors, growth factor receptor antagonists, transcription activators, and translation promoters); angiogenesis inhibitors, growth factor receptor antagonists, transcription repressors, translation repressors, replication inhibitors, inhibitory antibodies, antibodies against growth factors, bifunctional molecules composed of growth factors and cytotoxins, and bifunctional molecules composed of antibodies and cytotoxins as growth factor inhibitors); cholesterol lowering agents; vasodilators; and drugs that interfere with endogenous vasoactive mechanisms.

[0041] The scaffold 30 may be coated with a polymeric material. For example, the scaffold wires of the scaffold 30 may be partially or completely covered with a bioactive material, the bioactive material and the polymeric material being uniformly arranged. Furthermore, the polymeric coating may extend or penetrate the gaps between the scaffold wires to provide a hollow tube or cover on the inner or outer surface of the scaffold, thereby providing a scaffold-graft device. The polymeric material may be selected from the group consisting of polyester, polypropylene, polyethylene, polyurethane, polynaphthalene, polytetrafluoroethylene, expanded polytetrafluoroethylene, silicon, and combinations thereof. The cover may be in the form of a tubular structure. The silicon cover may be suitably formed by dip-coating the scaffold. The invention is not limited to forming a silicon film by dip-coating, but other techniques such as spraying may be suitably used. After the silicon coating or silicon film is applied to the scaffold, the silicon may be cured. Curing may be, for example, a short-duration low-temperature curing from about room temperature to about 90°C, said time being, for example, from about 10 minutes or more to about 16 hours. The cured silicon cover may also be sterilized by electron beam irradiation, gamma radiation, ethylene oxide treatment, etc. Argon plasma treatment may also be used to treat the cured silicon. Among other aspects, argon plasma treatment of cured silicon modifies the surface of the cured silicon, thereby reducing surface tack. However, the present invention is not limited to scaffold graft devices with polymer coatings. The graft portion can suitably be formed from polymer films, polymer strips, polymer tubes, polymer sheets, and textile materials. The textile material can be spun, knitted, braided, and / or wound with fibers to provide a suitable graft.

[0042] Various biocompatible polymer materials can be used as textile materials to form textile structures, including polyethylene terephthalate (PET), naphthalene ester derivatives such as polyethylene naphthalate, polybutylene naphthalate, polypropylene naphthalate, ePTFE, natural silk, polyethylene, and polypropylene. Furthermore, textile materials and scaffold materials can be co-formed (e.g., co-woven) to form scaffold graft devices.

[0043] Various self-expanding scaffolds can be employed in this invention. Self-expanding scaffolds can include scaffolds with a spring-like action that causes radial expansion of the scaffold, or scaffolds that expand due to the memory properties of the scaffold material for a specific configuration at a certain temperature. Nitino is a material that performs well in both a spring-like mode and a temperature-based memory mode. Other materials such as stainless steel, platinum, gold, titanium, and other biocompatible metals are also considered, as well as polymer scaffolds including biodegradable and bioabsorbable scaffolds. The scaffold configuration can also be selected from a wide range of geometries. For example, wire scaffolds, with or without corrugations or serrations in the wire, can be fastened into a continuous helical pattern to form a radially deformable scaffold. Individual loops or circular members can be linked together, such as by struts, stitching, welding, or crossing or locking, to form a tubular scaffold. Tubular scaffolds used in this invention also include those formed by etching or cutting patterns from a tube. Such scaffolds are commonly referred to as slotted scaffolds. Furthermore, scaffolds can be formed by etching patterns into the material or mold and depositing the scaffold material, such as by chemical vapor deposition, into the patterns.

[0044] The support conveying system 100 uses a support conveying device 1, which includes an inner sheath 10, an outer sheath 20, and a support stop 60. As described above, the inner sheath 10 and the outer sheath 20 may be hollow tubes. The inner sheath 10 is arranged inside the outer sheath 20 in a manner that allows it to slide relative to each other. In other words, the outer sheath 20 can slide on the inner sheath 10, and / or the inner sheath 10 can slide within the outer sheath 20.

[0045] The inner sheath 10 includes a proximal end 16 and an opposite distal end 18. The outer sheath 20 includes a proximal end 26 and a distal end 28. It should be noted that the term "distal" in this document refers to the direction away from the proximal handle 40, while the term "proximal" refers to the direction towards the proximal handle 40.

[0046] The inner sheath 10 and / or outer sheath 20 may be made of any suitable biocompatible material, such as, but not limited to, polymers and materials, including fillers such as metals, carbon fibers, glass fibers, or ceramics, and combinations thereof. Usefully but not limitingly, polymeric materials include polyethylene, polypropylene, polyvinyl chloride, polytetrafluoroethylene, fluorinated ethylene propylene copolymers, polyvinyl acetate, polystyrene, polyethylene terephthalate, naphthalene ester derivatives (such as polyethylene naphthalate, polybutylene naphthalate, polypropylene naphthalate, and polyurethane), polyurethane, polyurea, silicone rubber, polyamide, polycarbonate, polyaldehyde, natural rubber, polyester copolymers, styrene-butadiene copolymers, polyethers, fully or partially halogenated polyethers, polyamide-polyether polyesters, and copolymers and combinations thereof.

[0047] Furthermore, the inner sheath 10 and / or outer sheath 20 can be reinforced to provide greater strength while minimizing the overall tube profile. For example, the inner sheath 10 and / or outer sheath 20 may have reinforcing material wrapped around or otherwise arranged on or within the tube, such as polymer, metal, or ceramic strands or strips. The reinforcing strands or strips may be braided, woven, wound, and always form a reinforcing member for the tube.

[0048] like Figure 2A As shown, the support stop 60 of the support conveying device 1 includes a stop body 62, which may be disposed at or near the proximal end 16 of the inner sheath 10. The support stop 60 also includes at least one protrusion 66, which is attached to or protrudes from the stop body 62. The protrusion 66 is configured to hold or secure the support 30 during operation of the support conveying device 1.

[0049] like Figure 2B As shown, the support 30 is arranged on the outer surface 14 of the inner sheath 10. The support 30 is a hollow tubular device with an open lattice wall structure having a proximal end 31 and an opposite distal end 32. Figure 2B As shown, the protrusion 66 of the bracket stop 60 securely holds or restrains a diamond-shaped mesh at the proximal end 31 of the bracket 30.

[0050] Figure 3 This is a plan view of a stent 30 partially unfolded within a body cavity according to an embodiment of the present invention.

[0051] like Figure 3 As shown, according to an exemplary embodiment, the stent delivery device 1 partially deploys the stent 30. Specifically, after the stent delivery device 1 is placed within the body cavity 80, the outer sheath 20 can retract or slide away from the inner sheath 10. As the outer sheath 20 retracts in the "A" direction, the exposed distal end 32 of the stent 30 expands against the wall of the body cavity 80. When the distal end 28 of the outer sheath 20 retracts past the proximal end 16 of the inner sheath 10 on which the stent stop 60 is disposed, the stent 30 can be fully deployed together with the body cavity 80. The stent delivery device 1 can retract from the body cavity 80, leaving the deployed stent 30 within the body cavity 80. Before the stent 30 is fully deployed, that is, before the distal portion 28 of the outer sheath 20 retracts past the stent stop 60 disposed on the proximal end 16 of the inner sheath 10, the stent 30 can be repositioned within the body cavity 80. The outer sheath 20 can be repositioned on the inner sheath 10, for example by sliding, to recapture the stent 30 between the inner and outer sheaths. The stent delivery device 1 can then be repositioned within the body cavity 80 and subsequently re-deployed.

[0052] Figure 4This is a perspective view of a bracket stop 60 according to an exemplary embodiment. Figure 4 The bracket stop 60 in the diagram is enlarged for illustrative purposes. Figure 5 This is a side view of a bracket stop according to an exemplary embodiment. Figure 4 As shown, the bracket stop 60 may include a circumferential stop body 62, and a protrusion 66 extending radially outward from the circumferential stop body 62.

[0053] like Figure 4 As shown, the support stop 60 is a hollow tubular device. For illustrative purposes, Figure 4 Only one protrusion 66 located on the bracket stop 60 is shown. However, the bracket stop 60 of the present invention is not limited to only one protrusion 66 attached to the stop body 62. As will be explained later, the bracket stop 60 may include a pair of opposing protrusions 66, such that the protrusions 66 may be opposite to each other, or in other words, arranged at approximately 180 degrees to each other. The bracket stop 60 may also include more than two protrusions 66, which may be arranged around the stop body 62 at regular or irregular intervals.

[0054] Protrusion 66 can be a low-profile protrusion. Useful low-profile protrusions include, but are not limited to, round protrusions, convex protrusions, semi-circular protrusions, leaf-shaped protrusions, fin-shaped protrusions, etc.

[0055] exist Figure 4 In the exemplary embodiment shown, the protrusion 66 of the support stop 60 extends radially outward from the stop body 62 and includes a distal surface 66a, an upper surface 66b, a proximal surface 66c, and two side surfaces 66d. The protrusion 66 may have a bottom surface 66e attached to the stop body 62 (in... Figure 9A Alternatively, the bottom surface 66e of the protrusion 66 may be integrally formed with the stop body 62.

[0056] The distal surface 66a of the protrusion 66 is configured to have a generally trapezoidal shape that narrows outward from the outer periphery of the stop body 62. With this configuration, the distal surface 66a does not impede the process of the support 30 disengaging radially outward along the stop body 62 or the inner sheath 10.

[0057] The upper surface 66b of the protrusion 66 is formed between the distal surface 66a and the proximal surface 66c, and can be configured to have a generally trapezoidal shape that narrows toward the proximal surface 66c along the longitudinal (axial) direction of the stop body 62 or the inner sheath 10.

[0058] The proximal surface 66c is a concave surface, which includes a recess extending toward the distal surface 66a into the body of the protrusion 66, as seen in, for example, in a side view of the support stop 60. Figure 5As shown, the proximal surface 66c includes two inclined surfaces ( Figure 8C 665a and 665b), and can be formed by cutting into the distal side of the stop body 62 along the longitudinal direction of the inner sheath 10. The two inclined surfaces are inclined at different angles toward the distal surface 66a, thereby forming a recess extending into the body of the protrusion 66. As will be described later... Figures 8A-8C As shown, the proximal surface can be an inclined surface, a curved surface, or any surface including a recess extending into the body of the protrusion 66 and adapted for recapture and re-release of the stent 30. The wires of the stent 30 engaging with the proximal surface 66c can be partially received by the recess of the proximal surface 66c, such as... Figure 8C As shown.

[0059] With this configuration, the support 30 is constrained on the proximal surface 66c by engaging the mesh 32 at the proximal end 31 of the support 30. As a result, the support 30 is prevented from detaching from the outer diameter of the stop 60 during recapture operations.

[0060] The two side surfaces 66d of the protrusion 66 are respectively connected to the distal surface 66a, the upper surface 66b, the proximal surface 66c, and the bottom surface 66e (or the stop body 62). Since the support 30 includes wires with a diamond-shaped mesh at its proximal end 31, both side surfaces 66d can be configured to have a suitable shape that does not interfere with the mesh shape of the support 30 and does not impede the disengagement of the support 30 from the stop 60. For example, the two side surfaces can be recessed towards each other to increase the space used by adjacent wires of the support 30.

[0061] The structure of the protrusion 66 is designed to provide maximum contact area with the wires of the support 30 so as to hold the support 30 during deployment, repositioning and / or recapture.

[0062] The protrusion 66 may also be a hollow component. The protrusion 66 may be wholly or partially elastic to be adapted, for example, to fit between the inner sheath 10 and the outer sheath 20 by compression, or better, to releasably grip and / or retain the support 30. The protrusion 66 may also be a coated protrusion, such as a metal or stainless steel coated with an elastic polymer. Furthermore, the protrusion 66 may comprise a material, such as a polymeric material, having a degree of adhesiveness for better releasable grip and / or retention of the support 30. If the protrusion 66 is integrally formed with the stop body 62, the protrusion 66 may be made of the same material as the stop body 62.

[0063] The stop body 62 of the bracket stop 60 is constructed to be as thin as possible to minimize the size of the bracket stop 60.

[0064] The stent stop 60 can be made of any biocompatible metal (ideally stainless steel) or polymeric material. The stent stop 60 can be manufactured using any suitable technique, such as, but not limited to, electrical discharge machining (EDM) or metal injection molding. Furthermore, the stent stop 60 can be made from a single piece of metal using metal stamping techniques. For example, stainless steel can be stamped to form the protrusion 66. The stent body 62 can be formed around the inner sheath 10 and glued, rolled, or die-forged into place.

[0065] This invention is not limited to, for example Figure 4 The bracket stop 60 shown has a shape that can be used in other low-profile bracket stop configurations. As will be explained later, the bracket stop 60 may include a pair of opposing protrusions extending radially outward from the circular stop body 62 (in... Figure 13B (in the middle). The bracket stop 60 may include three protrusions evenly arranged on the circular stop body 62 (in Figure 13C (in the middle). The bracket stop 60 may include four protrusions evenly arranged on the circular stop body 62 (in Figure 13D (Middle). Other numbers of protrusions can also be used.

[0066] Furthermore, the present invention is not limited to, for example Figure 4 The radially outwardly extending protrusion 66 shown, and any suitable construction used for the low-profile radially outwardly extending protrusion, can be applied to the present invention.

[0067] Figures 6A-6B This is a planar top view schematically showing some exemplary constructions of the upper surface 66b.

[0068] like Figure 6A As shown, the upper surface 66a can be configured to have a trapezoidal shape 660. This configuration can be shaped to conform to the reduced-diameter arcuate shape of the support grid. With this configuration, when the support 30 is placed on and constrained by the support stop 60, the contact area between the stretched wires of the support grid of the support 30 and the side surface 66d of the support stop 60 increases. As a result, a strong and stable constraint force is obtained in the longitudinal direction of the stop body 62 or the inner sheath 10, and a more stable constraint of the support stop 60 on the support 30 becomes possible.

[0069] like Figure 6BAs shown, the upper surface 66a can be configured into a generally semi-elliptical (generally semi-rhomboid) shape 661 with a narrower arc towards the proximal side of the inner sheath 10. This configuration can be shaped to conform to the reduced-diameter arcuate shape of the support grid of the support 30. With this configuration, when the support 30 is placed on and constrained by the support stop 60, the contact area between the wires of the stretched support grid of the support 30 and the side surface 66d of the support stop 60 is increased. As a result, a strong and stable constraint force is obtained in the longitudinal direction of the stop body 62 or the inner sheath 10, and a more stable constraint of the support 30 by the support stop 60 becomes possible.

[0070] Figure 7 This is a schematic diagram of the structure of the upper surface 66b shown in the figure. (See diagram for example.) Figure 7 As shown, the structure of the upper surface 66b is configured to increase the contact area by matching the shape of the upper surface 66b of the protrusion 66 to the shape of a stretched support grid constrained by the protrusion 66, such as by hooking. Angle α (>0°) is defined by the projection of the two longitudinally intersecting edges 666 and 667 of the upper surface 66b. Length W1 is the width of the proximal end of the upper surface 66b (the distance between the two edges 666 and 667 at the proximal end of the upper surface 66b). Angle β (>0°) is defined by two longitudinally intersecting tangents L1 and L2 drawn on the two curved wire portions 301 and 302 of the support 30. Length W2 is the width between the two curved wire portions 301 and 302 at two points P1 and P2, where the two curved wire portions 301 and 302 contact the proximal end of the upper surface 66b at the two points P1 and P2. In this exemplary embodiment, W1 = W2, and α = β or α < β is acceptable.

[0071] Figures 8A-8C These are schematic side views illustrating different shapes of the recesses on the proximal surface 66c according to different exemplary embodiments. Figure 8A As shown, the proximal surface 66c may include a ramp 663 that slopes toward the distal surface 66a, thereby forming a recess extending toward the distal surface 66a. Alternatively, the proximal surface 66c may be configured to have a tapered shape projecting from the stop body 62. Figure 8B As shown, the proximal surface 66c can be configured to have an arcuate shape 664, which opens toward the proximal surface 66c, thereby forming a recess extending toward the distal surface 66a. Figure 8CAs shown, the proximal surface 66c can be configured to have a plurality of slopes, including a first slope 665a and a second slope 665b, thereby forming a recess extending toward the distal surface 66a. The first slope 665a and the second slope 665b are inclined at different angles, thereby forming a two-step structure. Alternatively, the proximal surface 66c can be configured to have a multi-step conical shape, including a first conical shape and a second conical shape protruding from the stopper body 62.

[0072] Figures 9A-9C FIG. is a schematic diagram showing the structural relationship between the proximal surface 66c and the stent 30. The stent 30 is represented by circles indicating cross-sections of grid wires along the edge of the stent 30. The stent 30 is longitudinally constrained within the inner sheath 10 or the stopper body 62. The proximal surface 66c serves as a receiving portion where the stent 30 is constrained. In embodiments including a recess in the proximal surface 66c, the function of the receiving portion is enhanced. The receiving portion has a height "h" measured as the distance between the stopper body 62 and the upper surface 66b. The wire of the stent 30 has a diameter "D". Figure 9A FIG. shows that the height "h" of the receiving portion (proximal surface 66c) is less than the radius (r, which is half of the diameter "D") of the wire as shown. In this case (i.e., h < r), when the stent 30 is subjected to a longitudinal load, the stent 30 cannot be constrained by the proximal surface 66c of the stent stopper 60, and thus there is no effect of longitudinally constraining the stent 30. Therefore, the height "h" of the proximal surface 66c should be greater than the radius of the stent wire, as Figure 9C shown.

[0073] Figure 9B FIG. shows a case where the height "h" of the receiving portion (proximal surface 66c) is greater than the diameter "D" of the wire of the stent 30. In this case, the stent 30 cannot be detached (or released) from the proximal surface 66c.

[0074] To enable the stent 30 to be smoothly detached / released from the proximal surface 66c of the stent stopper 60, as Figure 12 shown, the sum "s" of the height "h" of the proximal surface 66c and the radius of the outer diameter surface of the stopper body 62 is preferably less than the inner radius "r" of the fully expanded stent 30. With this configuration, the stent stopper 60 can longitudinally constrain the stent 30, but does not prevent the detachment or release of the stent 30.

[0075] Figure 10A and Figure 10B FIG. is a schematic diagram showing the structural relationship between the proximal surface 66c (664 and 665a / 665b) and the stent 30. The proximal surface 66c also has an axial length "L". As Figures 9A-9CAs shown, the axial length "L" of the proximal surface 66c (663) is defined as the axial distance between the proximal ends of the upper surface 66b and the bottom surface 66e. Figure 10A As shown, the axial length "L" of the proximal surface 66c (664) is the depth (or bow height) of the arcuate shape of the proximal surface 66c (664). Figure 10B As shown, the axial length “L” of the proximal surfaces 66c (665a and 665b) is defined as the axial distance between the proximal ends of the upper surface 66b and the bottom surface 66e (or the point where the proximal surface 66c intersects with the body 62).

[0076] In an exemplary embodiment, the axial length "L" of the receiving portion (proximal surface 66c) is preferably less than or equal to the radius of the wire of the bracket 30, such that the proximal surface 66c does not obstruct the bracket 30 from disengaging from the bracket stop 60. If the axial length "L" of the receiving portion (proximal surface 664) is greater than the radius of the wire of the bracket 30, the bracket 30 cannot smoothly self-expand and release from the bracket stop 60.

[0077] In short, the height of the proximal surface 66c of the bracket stop 60 is greater than the radius of the wire of the bracket 30, and the sum of the height "h" of the proximal surface 66c and the radius of the outer diameter surface of the stop body 62 is less than the inner radius of the fully expanded bracket 30. Furthermore, the axial length "L" of the proximal surface 66c is less than or equal to the radius of the wire of the bracket 30.

[0078] Figure 11 This is a schematic cross-sectional view illustrating the structure of the bracket stop 60 according to an exemplary embodiment. Figure 11 As shown, the stop body 62 of the bracket stop 60 is arranged around the inner sheath 10. The bracket 30 is constrained by the protrusion 66 of the bracket stop 60, such that the two wire portions 301 and 302 sandwich the two side surfaces 66d of the protrusion 66 in the middle.

[0079] Figure 12 This is a side view schematically illustrating the further structural relationship between the stent stop 60 and the fully expanded stent 30 according to an exemplary embodiment. As described above, the sum of the height "h" of the proximal surface 66c and the radius "s" of the outer diameter surface of the stop body 62 is preferably less than the inner radius "r" of the fully expanded stent 30. With this structure, the stent stop 60 can be inserted into the internal opening of the expanded stent, and the expanded stent can be positioned longitudinally past the protrusion 66 to securely re-capture the stent 30. Simultaneously, the stent stop 60 does not impede the disengagement or release of the stent 30.

[0080] Figures 13A-13D An example of a bracket stop 60 according to an additional embodiment is shown. Figure 13A As shown, the bracket stop 60 may have only one protrusion 66 formed on the stop body 62. Figure 13B As shown, the bracket stop 60 may have two protrusions 66 symmetrically formed on the stop body 62. For example... Figure 13C As shown, the bracket stop 60 may have three protrusions 66 evenly spaced around the stop body 62. Figure 13D As shown, the bracket stop 60 may have four protrusions 66 evenly spaced around the stop body 62. This invention is not limited to... Figures 13A-13D The structure shown. The bracket stop 60 of the present invention may have more than four protrusions 66, which may be arranged symmetrically relative to each other, or evenly spaced around the stop body 62, or evenly spaced in groups around the stop body 62, or unevenly spaced around the stop body 62.

[0081] Figures 14A-14C This is a schematic diagram illustrating a structural variation of the bracket stop according to an additional embodiment. Specifically, the bracket stop can be modified to include a protrusion with a radially outward slope on the stop body, as long as the bracket stop does not obstruct the disengagement of the bracket. For example, each vertex of the polygon has a radially outward slope.

[0082] Figure 14A The cross-sectional shape of a modified support stop 60-1 is shown, wherein the vertices of an equilateral triangle are truncated, and the wires of the support 30 can be constrained at each truncated vertex. In this exemplary modification, the support stop 60-1 is configured not to impede the movement of the outer sheath 20 to release and recapture the support 30 in the delivery system 100. Specifically, the dimensions of the support stop 60-1 are predetermined to reduce the frictional force generated between the stop 60-1 and the outer sheath 20 when the outer sheath 20 slides, and to facilitate the release / recapture operation of the support 30. Therefore, the length from the center of the stop 60-1 to each farthest vertex is preferably less than the inner radius of the outer sheath 20. Figure 14A As shown, if the inner radius of the outer sheath 20 is R, and the length from the center of the stop to each cut-off vertex is r, then there exists a relationship r < R.

[0083] In this configuration, when the support 30 is restrained by the support stop 60-1, any wires of the support 30 not captured by the protrusion 66-1 reside in the space S-1 between the outer sheath 20 and the stop 60-1. The volume of space S-1 is set to be sufficient to accommodate those wires not captured by the protrusion 66-1, relative to the volume of the wires in the support 30. Therefore, the friction between the wires of the support 30 and the inside of the outer sheath 20 can be reduced, thereby facilitating the release / recapture operation of the conveying system.

[0084] Figure 14B Another exemplary variation of the support stop 60-2 is illustrated, which aims to further improve the release / recapture operability of the conveying system 100, in addition to increasing the longitudinal restraint of the support 30 by further increasing the space between the outer sheath 20 and the stop 60-2. Specifically, Figure 14A The straight edge of the cross-sectional shape of the stop 60-1 is formed into a concave curve at the center of the stop body 62-2 to widen the space between the outer sheath 20 and the stop 60-2. Figure 14B The stop 60-1 shown is only used with Figure 14B Compare with stop component 60-2. For example... Figure 14B As shown, a space S-2 is formed between the outer sheath 20 and the stop 60-2, and the wire of the bracket 30 that is not captured by the protrusion 66-2 resides in space S-2. Compared to space S-1, space S-2 extends further inward in the radial direction, and is therefore larger than... Figure 14A The space S-1. Therefore, the deformable stop 60-2 can provide more space to accommodate the wires of the bracket 30.

[0085] Figure 14C Another improved stop 60-3 is shown, which is also configured to further increase the space between the support stop and the outer sheath to achieve a greater effect than... Figure 14A The deformation effect is better in the middle. With Figure 14B Differently, Figure 14C The deformed stop 60-3 is constructed to have a protrusion at the center of the body 62-3. Figure 14C The stop 60-1 shown is only used with Figure 14C The stop component 60-3 is compared. For example... Figure 14C As shown, a space S-3 is formed between the outer sheath 20 and the stop 60-3c, and the wire of the bracket 30 that is not captured by the protrusion 66-3 resides in space S-2. Space S-3 is larger than the portion of the body 62-3 that extends radially inward beyond its center to create more space for the wire of the bracket 30. Figure 14A The space S-1. As a result, the deformable stop 60c can provide more space to accommodate the wires of the bracket 30.

[0086] Figure 15A and Figure 15B It is an explanation and Figure 14B and Figure 14C A schematic diagram of the various deformable combinations of the support 30. (See attached diagram.) Figure 15A and Figure 15B As shown, Figure 14B and Figure 14CThe deformation can increase the space between the inner sheath 10 and the outer sheath 20, thereby providing more space to accommodate the wires of the bracket 30.

[0087] While embodiments of the invention have been described and illustrated above, those skilled in the art should understand that these are examples of the invention and should not be considered limiting. Additions, omissions, substitutions, and other modifications may be made without departing from the spirit and scope of the invention. Therefore, the invention should not be considered limited by the foregoing description, but only by the scope of the appended claims.

Claims

1. A support conveying device for conveying a self-expanding support, the support conveying device comprising: The inner sheath includes a proximal end and a distal end; A support stop includes a body and at least one protrusion, the body being circumferentially disposed on at least a portion of the inner sheath at the proximal end, and the at least one protrusion extending radially outward from the body for releasably engaging a portion of the self-expanding support. as well as An outer sheath, which is slidably disposed on the inner sheath and the bracket stop, The at least one protrusion includes a distal surface, a proximal surface, and an upper surface formed between the distal surface and the proximal surface. The upper surface is configured to have a generally trapezoidal shape that narrows longitudinally toward the proximal surface of the inner sheath, and The proximal surface includes a recess extending into the body of the at least one protrusion toward the distal surface.

2. The support conveying device according to claim 1, characterized in that, The distal surface of the at least one protrusion has a generally trapezoidal shape that narrows outward from the outer periphery of the body.

3. The support conveying device according to claim 1, characterized in that, The at least one protrusion includes two side surfaces configured to be recessed toward each other.

4. The support conveying device according to claim 1, characterized in that, The proximal surface includes a slope extending toward the distal surface.

5. The support conveying device according to claim 1, characterized in that, The proximal surface includes multiple ramps, the multiple ramps including at least a first ramp and a second ramp that are inclined at different angles toward the distal surface.

6. The support conveying device according to claim 1, characterized in that, The proximal surface includes an arcuate surface that curves toward the distal surface.

7. The support conveying device according to claim 1, characterized in that, The bracket stop includes two opposing protrusions.

8. The support conveying device according to claim 7, characterized in that, The two protrusions are arranged circumferentially and symmetrically on the main body.

9. The support conveying device according to claim 1, characterized in that, The bracket stop includes multiple protrusions that are evenly arranged around the outer periphery of the main body.

10. The support conveying device according to claim 1, characterized in that, The self-expanding stent includes a mesh of wires that engages with the proximal surface. The proximal surface has a height from the body, and The height is greater than the radius of the wire.

11. The support conveying device according to claim 10, characterized in that, The self-expanding stent includes a mesh of wires that engages with the proximal surface. The proximal surface has an axial length, and The axial length is less than the radius of the wire.

12. The support conveying device according to claim 11, characterized in that, The main body includes an outer radius, and when the support is fully expanded, the self-expanding support includes an inner radius. The sum of the height of the proximal surface and the outer radius of the body is less than the inner radius of the fully expanded stent.

Images