Medical implant for closing a vessel

Abstract

A medical implant for closing a vessel. The medical implant comprises a flexible tubular sleeve having a lumen and defining a longitudinal axis, the flexible tubular sleeve having a radially expanded configuration and a radially contracted configuration. The medical implant further comprises a fluid blocking portion for at least partially blocking the flow of fluid through the lumen; and an adhesive layer disposed on a radial outside surface of the flexible tubular sleeve for bonding to a wall of the vessel.

Description

[0001] Medical Implant for Closing a Vessel

[0002] Technical Field

[0003] The present disclosure relates to a medical implant for blocking or restricting the flow of fluid through a vessel , and a method of blocking or restricting the flow of fluid through a vessel .

[0004] Background

[0005] Medical implants for restricting or blocking a vessel can be used in the treatment of a number of medical conditions which require blood flow through a blood vessel to be restricted or blocked .

[0006] In some instances , the blood vessel through which the flow of blood is to be restricted or blocked may be a vein . For example , Chronic Venous Insuf ficiency ( CVI ) is a medical condition which occurs when the valves in a vein become damaged allowing blood to leak backwards thereby causing pooling of blood in the veins and elevated blood pressure . Such valve damage may occur as the result of aging, extended sitting or standing, or a combination of aging and reduced mobility .

[0007] CVI may be treated by inserting a medical implant into a damaged vein in order to block the flow of blood through that vein and thereby close that vein . This will result in blood rerouting to nearby healthy veins instead .

[0008] In other instances , the blood vessel through which the flow of blood is to be restricted or blocked may be an artery . For example , in order to treat some types of tumors , the arteries feeding blood to the tumor may be blocked or restricted with a medical implant to starve the tumor of blood, also known as tumor emboli zation . An abdominal aortic aneurysm (AAA) is a swelling or bulge in the aorta which can cause li fethreatening bleeding i f it ruptures . Medical implants may be inserted into arteries which feed the aneurysm in order to stop the flow of blood into the aneurysm . Medical implants may also be utili zed in other medical procedures such as balloon-occluded retrograde transvenous obliteration (BRTO) , or as preparation for large vital organ or tissue resections .

[0009] A number of medical implants exist in the art for blocking a blood vessel by vessel emboli zation . However, these devices can suf fer from migration where the device moves away from the treatment site resulting in suboptimal performance or device failure .

[0010] In view of the above , there is a need in the art for a new type of medical implant which can ef fectively block or restrict the flow of fluid through a vessel whilst having improved resistance to migration .

[0011] Summary

[0012] In a first aspect of the present disclosure , there is provided a medical implant for closing a vessel . The medical implant comprises a flexible tubular sleeve having a lumen and defining a longitudinal axis , the flexible tubular sleeve having a radially expanded configuration and a radially contracted configuration . The medical implant further comprises a fluid blocking portion for at least partially blocking the flow of fluid through the lumen; and an adhesive layer disposed on a radial outside surface of the flexible tubular sleeve for bonding to a wall of the vessel .

[0013] In some embodiments , this may result in a medical implant which can ef fectively block or restrict the flow of fluid through a vessel whilst having improved resistance to migration . The vessel may be a blood vessel such as an artery or a vein .

[0014] Throughout this disclosure , the term ' radially expanded configuration' refers to a configuration where the flexible tubular sleeve has a greater radial extent than in the ' radially contracted configuration' .

[0015] Throughout this disclosure , the term ' fluid blocking portion' or 'barrier' may refer to any element which can at least partially block the flow of fluid through the lumen of the flexible sleeve .

[0016] The flexible tubular sleeve may be substantially tubular in the expanded configuration and the contracted configuration .

[0017] In some embodiments , this may result in improved adhesion o f the flexible tubular sleeve to a vessel wall and easier insertion of the medical implant .

[0018] The flexible tubular sleeve may be configured to be disposed over an expandable balloon .

[0019] In some embodiments , this may allow the flexible tubular sleeve to be moved from the radially contracted configuration to the radially expanded configuration using a balloon .

[0020] The fluid blocking portion may be positioned at one end of the flexible tubular sleeve .

[0021] In some embodiments , this may result in ef fective blocking or restricting of fluid flow through the vessel . In some embodiments , this may further allow the flexible tubular sleeve to be disposed over a balloon .

[0022] The fluid blocking portion may comprise a fluid-proo f membrane . In some embodiments , this may result in ef fective blocking or restricting of fluid flow through the vessel .

[0023] The fluid-proof membrane may be integral with the flexible tubular sleeve .

[0024] The flexible tubular sleeve may be made from a biodegradable material .

[0025] In some embodiments , this may allow the flexible tubular sleeve to degrade over time .

[0026] The flexible tubular sleeve may comprise a collagen film or a polymer film . The flexible tubular sleeve may be a graft material .

[0027] In some embodiments , this may result in improved adhesion between the flexible tubular sleeve and the vessel wall .

[0028] The outside surface of the flexible tubular sleeve may comprise ribs , ridges or bumps .

[0029] In some embodiments , this may improve migration resistance of the medical implant .

[0030] The outside surface of the flexible tubular sleeve may comprise a plurality of ribs which are circumferentially disposed around the flexible tubular sleeve .

[0031] In some embodiments , this may improve migration resistance of the medical implant .

[0032] The medical device may further comprise a stent disposed within the flexible tubular sleeve .

[0033] In some embodiments , this may help to maintain the structural integrity of the medical implant . The stent may be fixed to an inner surface of the flexible tubular sleeve .

[0034] The flexible tubular sleeve may be a first flexible tubular sleeve . The medical device may further comprise a second flexible tubular sleeve and the stent may be disposed between the first flexible tubular sleeve and the second flexible tubular sleeve .

[0035] The stent may be a sel f-expanding stent .

[0036] In some embodiments , this may provide a mechanism to allow the flexible tubular sleeve to move from the radially contracted configuration to the radially expanded configuration .

[0037] The stent may be at least partially made from a shape-memory material .

[0038] The stent may comprise at least one of nitinol , stainles s steel , a cobalt-chromium alloy, magnesium, a polymer or a bioresorbable polymer .

[0039] The fluid blocking portion may be positioned within the lumen of the flexible tubular sleeve and may comprise a sponge material or swellable material for blocking fluid flow through the lumen of the flexible tubular sleeve .

[0040] In some embodiments , this may result in ef fective blocking or restricting of fluid flow through the vessel .

[0041] Throughout this disclosure , the term " sponge material" will be used to refer to a porous and absorbent material . The sponge material or swellable material may comprises one or more of : a swellable hydrogel , a non-moisture curing adhesive , collagen, or nanosilicate .

[0042] The sponge material or swellable material may comprise a thrombogenic material .

[0043] In some embodiments , this may result in improved emboli zation of the blood and therefore more ef fective blocking or restricting of fluid flow through the vessel .

[0044] The adhesive layer may comprise one or more of : microbial transglutaminase (mTG) , gelatin, cyanoacrylate , a lysine- based adhesive , a fibrin-based adhesive , polyvinylpyrollidone , or a N-hydroxy-succinimide-activated synthetic polymer .

[0045] The adhesive layer may comprise microbial transglutaminase (mTG) and gelatin .

[0046] In some embodiments , this may result in improved adhesion between the flexible tubular sleeve and the vessel wall .

[0047] The adhesive layer may cover at least 50% of the outer surface of the flexible tubular sleeve .

[0048] In some embodiments , this may result in improved migration resistance of the medical implant .

[0049] The medical implant may further comprise a sacri ficial layer disposed over the adhesive layer .

[0050] In some embodiments , this may protect the adhesive during introduction of the medical implant into the vessel and thereby result in improved adhesion between the flexible tubular sleeve and the vessel wall . The sacri ficial layer may comprise one or more of : polyvinyl alcohol , polyacrylic acid, polyethylene glycol , polyvinyl pyrrolidone , polyacrylamide , N- ( 2-hydroxypropyl ) methacrylamide , polyoxazolines , polyphosphoesters , polyphosphazenes , pectins , dextrans , hyaluronic acid, chitosan derivatives , carrageenan, cellulose or modi fied cellulose , starch or starch derivatives , or combinations thereof .

[0051] The sacri ficial layer may be conf igured to dissolve when the flexible tubular sleeve is introduced into a vessel .

[0052] The sacri ficial layer may be configured to break away when the flexible tubular sleeve expands from the collapsed configuration to the expanded configuration .

[0053] The outside surface of the flexible tubular sleeve has been surface treated by one or more of : chemical treatment with primers , laser treatment , UV radiation, and plasma treatment via addition, creation, and / or exposure of surface groups including reactive oxygen or nitrogen species .

[0054] In some embodiments , this may result in improved adhesion between the flexible tubular sleeve and the vessel wall .

[0055] The flexible tubular sleeve may comprise a proximal tubular section and a distal tubular section and the fluid blocking portion is positioned between the proximal tubular section and the distal tubular section .

[0056] The fluid blocking portion may comprise a longitudinal section or a membrane with a reduced lumen compared to the flexible tubular sleeve .

[0057] In some embodiments , this may result in ef fective blocking or restricting of fluid flow through the vessel . The fluid blocking portion may comprise a longitudinal section with a closed lumen to prevent fluid flow through the flexible tubular sleeve .

[0058] In some embodiments , this may result in ef fective blocking or restricting of fluid flow through the vessel .

[0059] The medical implant may further comprise a first stent section positioned within the proximal tubular section and a second stent section positioned within the distal tubular section and wherein the first stent section and the second stent section are not connected .

[0060] In some embodiments , this may result in improved resistance to migration of the medical implant .

[0061] In a second aspect of the present disclosure , there i s provided a medical device for sealing a vessel . The medical device comprises a catheter shaft defining a longitudinal axis ; an expandable balloon positioned at a distal end of the catheter shaft , the expandable balloon having a radially contracted configuration and a radially expanded configuration; and the medical implant of any of the above .

[0062] The balloon may comprise a cylindrical barrel portion .

[0063] The flexible tubular sleeve may be disposed at least over the cylindrical barrel portion of the balloon .

[0064] At least the portion of the outer surface of the flexible tubular sleeve disposed over the cylindrical barrel portion of the balloon may be coated with the adhesive layer .

[0065] The catheter shaft may have an inflation lumen in fluid connection with the balloon . In a third aspect of the present disclosure , there is provided a method of blocking or restricting the flow of fluid through a vessel . The method comprises inserting a medical implant having a flexible tubular sleeve into a vessel in a radially contracted configuration, the flexible tubular sleeve adapted to expand from the radially contracted configuration to a radially expanded configuration; bonding a radial outside surface of the flexible tubular sleeve to a wall of the vessel with an adhesive layer ; at least partially blocking the flow of fluid through the lumen of the medical implant with a fluid blocking portion .

[0066] Expanding the flexible tubular sleeve from the radially contracted configuration to the radially expanded configuration may comprise disposing the flexible tubular sleeve over a balloon and inflating the balloon .

[0067] Expanding the flexible tubular sleeve from the radially contracted configuration to a the radially expanded configuration comprises expanding a stent disposed within the flexible tubular sleeve .

[0068] The fluid blocking portion may comprise one or more of a membrane , a sponge material or a swellable material .

[0069] In a fourth aspect of the present disclosure , there i s provided a method blocking or restricting a flow of fluid through a blood vessel , the method comprising : bonding a flexible tubular sleeve having a lumen to a wall of the blood vessel ; and at least partially blocking the flow of fluid through the lumen of the flexible tubular sleeve with a barrier .

[0070] In a fi fth aspect of the present disclosure , there is provided a medical implant for blocking or restricting a flow of fluid through a vessel , the medical implant comprising : a flexible tubular sleeve having a lumen and defining a longitudinal axis , the flexible tubular sleeve having a radially expanded configuration and a radially contracted configuration; a restrictor or barrier associated with the flexible tubular sleeve for at least partially blocking the flow of fluid through the lumen; and an adhesive layer disposed on a radial outside surface of the flexible tubular sleeve for bonding to a wall of the vessel .

[0071] Brief Description of the Drawings

[0072] To enable better understanding of the present disclosure , and to show how the same may be carried into ef fect , reference will now be made , by way of example only, to the accompanying drawings , in which :

[0073] FIG . 1A shows a medical implant in a radially contracted configuration disposed over a balloon, according to one or more embodiments shown and described herein .

[0074] FIG . IB shows the medical implant of FIG . 1A in a radially expanded configuration disposed over a balloon, according to one or more embodiments shown and described herein .

[0075] FIG . 2A shows the medical implant of FIG . 1A being introduced into a vein, according to one or more embodiments shown and described herein .

[0076] FIG . 2B shows the medical implant of FIG . 1A in the radially expanded configuration within the vein, according to one or more embodiments shown and described herein .

[0077] FIG . 2C shows the medical implant of FIG . 1A after being implanted in the vein , according to one or more embodiments shown and described herein .

[0078] FIG . 3A shows another embodiment of a medical implant in a radially contracted configuration disposed over a balloon, according to one or more embodiments shown and described herein .

[0079] FIG . 3B shows the medical implant of FIG . 3A in a radially expanded configuration disposed over a balloon, according to one or more embodiments shown and described herein .

[0080] FIG . 4A shows another embodiment of a medical implant in a radially contracted configuration, according to one or more embodiments shown and described herein .

[0081] FIG . 4B shows the medical implant of FIG . 4A in a radially expanded configuration, according to one or more embodiments shown and described herein .

[0082] FIG . 4G shows a schematic cross-sectional view of the medical implant of FIG . 4B .

[0083] FIG . 5A shows the medical implant of FIG . 4A being introduced into an artery, according to one or more embodiments shown and described herein .

[0084] FIG . 5B shows the medical implant of FIG . 4A in the radially expanded configuration within the artery, according to one or more embodiments shown and described herein .

[0085] FIG . 6A shows another embodiment of a medical implant in a radially contracted configuration according to one or more embodiments shown and described herein .

[0086] FIG . 6B shows the medical implant of FIG . 6A in a radially expanded configuration, according to one or more embodiments shown and described herein .

[0087] Detailed Description FIGS . 1A and IB show a medical implant 100 for blocking or restricting the flow of fluid through a vessel , such as a blood vessel . The medical implant comprises a flexible tubular sleeve 110 with a lumen and defining a longitudinal axis L . An adhesive layer 120 is disposed on the radial outside surface of the flexible tubular sleeve 110 for bonding the flexible tubular sleeve 110 to a wall of a vessel . The medical implant 110 further comprises a fluid blocking portion or barrier, which may be in the form of a membrane 130 , which at least partially blocks the flow o f fluid through the lumen of the flexible tubular sleeve 110 .

[0088] The flexible tubular sleeve 110 may have a radially contracted configuration, as shown in FIG . 1A, and a radially expanded configuration, as shown in FIG . IB . In the radially expanded configuration, the diameter or radial extent of the flexible tubular sleeve 110 is greater than in the radially contracted configuration . The flexible tubular sleeve 110 may maintain a substantially tubular shape in both the radially contracted configuration and the radially expanded configuration, which may allow the flexible tubular sleeve to maintain a low profile when introduced into a vessel and may result in improved bonding between the flexible tubular sleeve 110 and a vessel wall when the flexible tubular sleeve 110 is in the radially expanded configuration . The flexible tubular sleeve 110 may be made from a number of suitable materials , including, for example , a collagen film or a polymer thin film . The collagen film may be , for example , an amniotic membrane or a medical grade collagen casing . The polymer thin film may include , for example , poly-l-lactic acid ( PLLA) , polylactic-co-glycolic acid ( PLGA) , poly ( 4- hydroxybutyrate ) ( P4HB ) , or polyurethane . These materials may help to bond the flexible tubular sleeve 110 with a vessel wall thereby resulting in improved resistance to migration of the medical implant 100 . The fluid blocking portion or barrier, which may be in the form of membrane 130 , may be disposed at a distal end 112 of the flexible tubular sleeve 110 . A proximal end 111 of the flexible tubular sleeve 110 may be an open end to allow a balloon catheter 10 to be inserted into the flexible tubular sleeve 110 . The membrane 130 may be formed integrally with the flexible tubular sleeve 110 and may be fluid proof to block the flow of fluid through the lumen of the flexible tubular sleeve 110 . The membrane 130 may be formed from the same materials as the flexible tubular sleeve 110 such as , for example , a collagen film or a polymer thin film . In some embodiments , the flexible tubular sleeve 110 and the membrane 130 may be made from a biodegradable material , such as PLLA or P4HB, such that the flexible tubular sleeve 110 and the membrane 130 slowly degrade over time once implanted into a vessel .

[0089] The adhesive layer 120 is disposed on the radial outside surface of the flexible tubular sleeve 110 and may help to bond the flexible tubular sleeve 110 to a vessel wall . FIGS . 1A and IB show the adhesive layer 120 disposed over the entire outer surface of the flexible tubular sleeve 110 . However, in some embodiments , the adhesive layer may not cover the entire outer surface of the flexible tubular sleeve but may cover anywhere between 50% to 100% of the outer surface of the flexible tubular sleeve 110 . The adhesive layer 120 may include one or more of microbial transglutaminase (mTG) , gelatin, cyanoacrylate , a lysine- based adhesive such as TissuGlu™, a fibrin-based adhesive such as Tisseel™, polyvinylpyrollidone , or a N-hydroxy- succinimide-activated synthetic polymer such as Progel™ .

[0090] In one embodiment , the adhesive layer may include microbial transglutaminase (mTG) and gelatin . The mTG may be in liquid, gel or powder form with a gelatin substrate to improve adhesion and increase dilution resistance . A synthetic polymer may further be included as a thickening agent . The combination of microbial transglutaminase (mTG) and gelatin provides for excellent adhesion performance .

[0091] The outer surface of the flexible tubular sleeve 110 may be surface treated in order to improve bonding between the adhesive layer 120 and the flexible tubular sleeve 110 , and thereby improve adhesion between the flexible tubular sleeve 110 and vessel wall . For example , the outer surface of the flexible tubular sleeve may be treated in one or more of the following ways : chemical treatment with primers such as EDTA or 1 O-methacryloyloxydecyl dihydrogen phosphate ( 10-MDP ) , laser treatment , UV irradiation, and plasma treatment via addition, creation, and / or exposure of surface groups such as reactive oxygen and nitrogen species including O2- , OH- , HOO+ , NO2- , and NO3- .

[0092] In the radially contracted configuration shown in FIG . 1A, the medical implant 100 may further comprise a sacri ficial layer 150 disposed over the adhesive layer 120 . The sacri ficial layer 150 may protect the adhesive layer 120 from moisture during insertion of the medical implant 100 into a vessel . Once the medical implant 100 has been introduced into the vessel and manoeuvred to the treatment site , the sacri ficial layer 150 will either dissolve or break away when the flexible tubular sleeve 110 moves from the radially contracted configuration to the radially expanded configuration . The sacri ficial layer 150 may include one or more of : polyvinyl alcohol , polyacrylic acid, polyethylene glycol , polyvinyl pyrrolidone, polyacrylamide , N- ( 2- hydroxypropyl ) methacrylamide , polyoxazolines , polyphosphoesters , polyphosphazenes , pectins , dextrans , hyaluronic acid, chitosan derivatives , carrageenan, cellulose or modi fied cellulose , starch or starch derivatives , or combinations thereof .

[0093] The flexible tubular sleeve 110 may be configured to be disposed over a balloon 12 of a balloon catheter 10 . The balloon catheter 10 may be a standard balloon catheter having a catheter shaft 11 with an inflation lumen connected to the balloon 12 positioned at a distal end of the catheter shaft 11 . The balloon 12 may have a cylindrical barrel portion 12a, a proximal conical portion 12b and a distal conical portion 12c . The flexible tubular sleeve 110 and the adhesive layer 120 may be substantially aligned with the barrel portion 12a . This may allow the flexible tubular sleeve 110 to maintain a substantially tubular shape when expanding from the radially contracted configuration to the radially expanded configuration and may provide better contact between the adhesive layer 120 and a vessel wall . The membrane 130 may be positioned over a distal end 13 of the balloon catheter 10 . In order to move the flexible tubular sleeve 110 from the radially contracted configuration to the radially expanded configuration, the balloon 12 may be inflated through the inflation lumen causing the balloon 12 and therefore the flexible tubular sleeve 110 to expand . The balloon 12 may be a compliant , semi-compliant or non-compliant balloon .

[0094] A method of introducing the medical implant 100 into a vessel and using it to block or restrict the flow of blood through the vessel is explained with reference to FIGS . 2A to 2C . The medical device 100 may be particularly suited to treatment of a vein, for example , to treat Chronic Venous Insuf ficiency ( CVI ) . However, the medical implant 100 could also be used in the treatment of arteries .

[0095] Firstly, the medical implant 100 , including the flexible tubular sleeve 110 , the adhesive layer 120 , membrane 130 and sacri ficial layer 150 may be positioned over the balloon 12 of the balloon catheter 10 . An access site may then be created in a vein V to allow access of a catheter into the vein V .

[0096] The balloon catheter 10 with the medical implant 100 may then be introduced into the vein V and manoeuvred to a treatment site in the vein where the flow of blood through the vein V is to be blocked or restricted . As shown in FIG . 2A, during introduction into and advancement of the catheter 10 and medical implant 100 through the vein V, the balloon is in the non-expanded state and the flexible tubular sleeve is in the radially contracted configuration . The sacri ficial layer 150 may protect the adhesive layer 120 from moisture and prevent it from dissolving or contacting the vessel wall in places other than the treatment site .

[0097] As shown in FIG . 2B, once the balloon 12 and medical implant 100 are positioned at the treatment site , the balloon 12 may then be expanded by inflating it with an inflation fluid which causes the flexible tubular sleeve 110 to expand from the radially contracted configuration to the radially expanded configuration . The sacri ficial layer 150 may either dissolve prior to the balloon 12 being inflated or may break away as the flexible tubular sleeve 110 is expanded . The adhesive layer 120 may therefore contact the venous walls at the treatment site when the flexible tubular sleeve 110 is in the radially expanded configuration and bond or adhere to the venous wall .

[0098] The balloon catheter 12 may then be deflated and the balloon catheter 10 may be removed from the vein V . As shown in FIG . 2C, the medical implant may be left in the vein V . The membrane 130 may block or restrict the flow of fluid through the lumen of the flexible tubular sleeve 110 and thereby block or restrict the flow of blood through the vein V . The combination of the adhesive layer 120 on the flexible tubular sleeve 110 and the fluid blocking portion or membrane 130 may result in ef fective blocking or restricting of blood through the vessel whilst improving resistance of the medical implant 100 to migration .

[0099] FIGS . 3A and 3B illustrate another embodiment of a medical implant 200 . The medical implant 200 is similar to medical implant 100 in that it comprises a flexible tubular sleeve 210 , an adhesive layer 220 disposed on a radial outside surface of the flexible tubular sleeve 210 and a fluid blocking portion, which may be in the form of a membrane 230 , disposed at a distal end 212 of the flexible tubular sleeve 210 . A proximal end 211 of the flexible tubular sleeve 210 may be open to allow it to be disposed over a balloon 12 of a balloon catheter 10 . A sacri ficial layer 250 may be disposed over the adhesive layer 220 . The flexible tubular sleeve may have a radially contracted configuration shown in FIG . 3A and a radially expanded configuration shown in FIG . 3B .

[0100] The materials for the flexible tubular sleeve 210 , adhesive layer 220 , membrane 230 and sacri ficial layer 250 may be the same as for the flexible tubular sleeve 110 , adhesive layer 120 , membrane 130 and sacri ficial layer 150 of medical device 100 described above .

[0101] Medical device 200 di f fers from medical device 100 in that the flexible tubular sleeve 210 further comprises a plurality of ribs 213 disposed on a radial outside surface . The ribs 213 may be circumferentially di sposed around the flexible tubular sleeve 210 . The adhesive layer 220 may cover the ribs 213 . FIG . 3A shows five circumferentially extending ribs 213 , however, the medical device 200 is not limited to any speci fic number of ribs and may comprise anywhere in the range of 2 to 100 ribs .

[0102] The ribs 213 may help to improve migration resistance and result in improved bonding between the adhesive layer 220 and the vessel wall .

[0103] The method of introducing the medical implant 200 into a vessel , such as a vein V, and using it to block or restrict the flow of blood through a vessel is the same as explained for medical device 100 in reference to FIGS . 2A-2C above . FIGS . 4A and 4B illustrate another embodiment of a medical implant 300 .

[0104] The medical implant 300 comprises a flexible tubular sleeve 310 , an adhesive layer 320 disposed on a radial outer surface of the flexible tubular sleeve 310 and a fluid blocking portion or barrier, which may be in the form of swellable matterial or sponge material 330 , and which may be positioned within a lumen of the flexible tubular sleeve 310 .

[0105] The flexible tubular sleeve 310 may have a radially contracted configuration shown in FIG . 4A and a radially expanded configuration shown in FIG . 4B . The flexible tubular sleeve 310 may be substantially tubular in both the radially contracted configuration and the radially expanded configuration . The flexible tubular sleeve 310 may be made from the same materials as flexible tubular sleeve 110 o f medical implant 100 described above .

[0106] The adhesive layer 320 is positioned on the radial outside surface of the flexible tubular sleeve 310 and may cover anywhere from 50% to 100% of the outer surface of the flexible tubular sleeve 310 . The adhesive layer 320 may be made from the same materials as adhesive layer 110 of medical implant 100 described above . In one embodiment , the adhesive layer 420 may include microbial transglutaminase (mTG) and gelatin . The mTG may be in liquid, gel or powder form with a gelatin substrate to improve adhesion and increase dilution resistance . A synthetic polymer may further be included as a thickening agent . The combination of microbial transglutaminase (mTG) and gelatin may provide for excellent adhesion performance .

[0107] The medical implant 300 may also include a sacri ficial layer 350 ( shown in FIG . 4A) which may cover the adhesive layer 320 during insertion of the medical implant 300 into a vessel and advancement through the vessel . The sacri ficial layer 350 may be made from the same materials as the sacri ficial layer 150 of medical implant 100 described above .

[0108] The outer surface of the flexible tubular sleeve 310 may also be surface treated in order to improve bonding between the adhesive layer 320 and the flexible tubular sleeve 310 , and thereby improve adhesion between the flexible tubular sleeve 310 and a vessel wall . The surface treatments for flexible tubular sleeve 310 may be the same as for flexible tubular sleeve 110 of medical implant 100 described above .

[0109] The medical implant 300 may further comprise a stent 340 which may be disposed within the flexible tubular sleeve 310 and fixed to a radial inner surface of the flexible tubular sleeve . The stent 340 may be a sel f-expanding stent and may also have a radially contracted configuration, as shown in FIG . 4A, and a radially expanded configuration, as shown in FIG . 4B . The stent 340 may be made from a number of suitable materials including, for example , nitinol , stainless steel , a cobalt-chromium alloy, magnesium, a polymer or a bioresorbable polymer . The stent 340 may provide stability to the flexible tubular sleeve 310 and may assist the flexible tubular sleeve 310 in expanding from the radially contracted configuration to the radially expansion configuration .

[0110] The sponge or swellable material 330 , which may be positioned within the lumen of the flexible tubular sleeve 310 , may include one or more of : a swellable hydrogel , a non-moisture curing adhesive , collagen, or nanosilicate . The sponge or swellable material 330 may restrict or block the flow of fluid through the lumen of the flexible tubular sleeve 310 . The sponge or swellable material 330 may have thrombogenic properties due to being made from a thrombogenic material , such as collagen or nanosilicate listed above , or may further include a thrombogenic material , such as polyester fibers or other fibers . The thrombogenic material may cause blood to clot thereby resulting in improved blocking or restricting of blood flow through the lumen of the flexible tubular sleeve .

[0111] Fig . 4C shows a schematic cross-sectional view of the medical implant 300 in the radially expanded configuration . FIG . 4C shows how the sponge or swellable material 330 is positioned within the lumen of the flexible tubular sleeve 310 . The stent 340 is attached to an inner surface of the flexible tubular sleeve 310 and thereby positioned between the flexible tubular sleeve 310 and the sponge or swellable material 330 . The adhesive layer 320 is disposed on the radial outside surface of the flexible tubular sleeve 310 .

[0112] A method of introducing the medical implant 300 into a vessel and using it to block or restrict the flow of blood through the vessel is explained with reference to FIGS . 5A and 5B . The medical device 300 may be particularly suited to treatment of an artery, for example , in tumor emboli zation, treatment of abdominal aortic aneurysms (AAA) , balloon- occluded retrograde transvenous obliteration (BRTO) , or as preparation for large vital organ or tissue resections . However, the medical implant 300 could also be used in the treatment of veins .

[0113] Firstly, an access site into an artery A is created . The medical implant 300 may then be loaded into a catheter 30 and inserted into the artery A through the access site . The catheter 30 and medical implant 300 may then be advanced through the artery A to a treatment site where the flow o f blood through the artery is to be restricted or blocked . As shown in FIG . 5A, during the insertion into the artery A and advancement through the artery A, the medical implant 300 may be in the radially contracted configuration . The sacri ficial layer 350 may protect the adhesive layer 320 from moisture and prevent it from dissolving or contacting the vessel wal l in places other than the treatment site . Once the medical implant 300 is positioned at the treatment site , the medical implant 300 may be pushed out of the catheter 30 and the catheter 30 may be retracted . The stent 340 may be a sel f-expanding stent , such that the medical implant 300 , including the flexible tubular sleeve 310 , expands from the radially contracted configuration to the radially expanded configuration, as shown in FIG . 4B . The sacri ficial layer 350 may either dissolve prior to the stent 340 expanding or may break away as the flexible tubular sleeve 310 is expanded . The adhes ive layer 320 may therefore contact the walls of the artery A at the treatment site when the flexible tubular sleeve 310 is in the radially expanded configuration and bond or adhere to the walls of the artery .

[0114] The sponge or swellable material 330 may restrict or block the flow of blood through the lumen of the flexible tubular sleeve 310 and thereby restrict or block the flow of blood through the artery A. The sponge or swellable material 330 may also include thrombogenic material which may cause the blood to clot within the lumen of the flexible tubular sleeve 310 thereby resulting in improved restriction or blocking of blood flow through the artery A. The bonding of the flexible tubular sleeve 310 to the vessel wall with the adhesive layer 320 results in improved resistance to migration of the medical implant 300 .

[0115] FIGS . 6A and 6B illustrate another embodiment of a medical implant 400 .

[0116] The medical implant comprises a flexible tubular sleeve having a proximal tubular section 410a and a distal tubular section 440b . A first stent section 440a may be positioned within the proximal tubular section 410a and a second stent section 440b may be positioned within the distal tubular section 410b such that they are not connected . An adhesive layer 420 may be disposed on a radial outside surface of the proximal tubular section 410a and a distal tubular section 440b . A sacri ficial layer 450 may be disposed over the adhesive layer 420 . A fluid blocking portion or barrier may be positioned between the proximal tubular section 410a and the distal tubular section 440b . The fluid blocking portion may be in the form of a membrane 430 forming a longitudinal section having a reduced lumen compared to the proximal tubular section 410a and the distal tubular section 440b or forming a longitudinal section having a closed lumen .

[0117] The proximal tubular section 410a and the distal tubular section 440b of the flexible tubular sleeve may have a radially contracted configuration, shown in FIG . 6A, or a radially expanded configuration shown in FIG . 6B . The proximal tubular section 410a and the distal tubular section 440b of the flexible tubular sleeve may be made from the same material as the flexible tubular sleeve 110 of medical implant 100 described above . Similarly, the outer surface of the flexible tubular sleeve section 410a, 410b may also be surface treated in order to improve bonding between the adhesive layer 420 and the flexible tubular sleeve section 410a, 410b, and thereby improve adhesion between the flexible tubular sleeve 410 and a vessel wall . The surface treatments for flexible tubular sleeve 410 may be the same as for flexible tubular sleeve 110 of medical implant 100 described above .

[0118] The adhesive layer 420 and the sacri ficial layer 450 may be made from the same materials as adhesive layer 110 and sacri ficial layer 150 , respectively, of medical implant 100 described above . The first stent section 440a and the second stent section 440b may be sel f-expanding stent sections and may be made from the same materials as stent 340 of medical implant 300 described above .

[0119] The membrane 430 may be made from the same materials as membrane 130 of medical implant 100 described above . The membrane 430 may have a reduced or closed lumen compared to the lumen of the proximal tubular section 410a and the distal tubular section 440b . The membrane 430 may therefore restrict or block the flow of fluid through the medical implant 400 and therefore the vessel in which the medical implant 400 is disposed . The membrane 430 may be integral with the proximal tubular section 410a and the distal tubular section 440b .

[0120] The medical implant 400 may be advantageous in restricting or blocking the flow of blood through a vessel having a tortuous anatomy . The proximal tubular section 410a and the distal tubular section 440b with a membrane in the middle provide the medical implant with increased flexibility to allow it to more easily navigate tortuous vessel anatomy .

[0121] The method of introducing the medical implant 400 into a vessel and using it to block or restrict the flow of blood through the vessel may be the same as for medical implant 300 described in relation to FIGS . 5A and 5B above .

[0122] Various modi fications will be apparent to those skilled in the art .

[0123] The medical implants 100 , 200 may also comprise a stent positioned within the flexible tubular sleeve 110 , 210 . The stent may be a sel f-expanding stent or a non-sel f-expanding stent .

[0124] The membrane 130 may be closed or may an opening to allow some flow of fluid through the lumen of flexible tubular sleeve 110 .

[0125] The membrane 130 may not be integral with the flexible tubular sleeve 110 but may be separate and made from a di f ferent material than the tubular sleeve 110 . The membrane 130 may be attached to the flexible tubular sleeve 110 , for example , with an adhesive , a mechanical connection or with an ultrasonic weld . The medical implants 100, 200 may have sponge or swellable material disposed within a section of the lumen of the flexible tubular sleeve 110, 210.

[0126] The medical implant 200 is not limited to having circumferential ribs 213 but may instead, for example, have bumps or ridges.

[0127] The flexible tubular sleeves 310, 410 may also be provided with ribs, bumps or ridges.

[0128] The flexible tubular sleeve 310, 410 may be a first flexible tubular sleeve and the medical device 300, 400 may further comprise a second flexible tubular sleeve. The stent 340, 440 may be disposed between the first flexible tubular sleeve 310, 410 and the second flexible tubular sleeve.

[0129] The stent 340, 440a, 440b may not be a self-expanding stent.

[0130] The medical implant 400 may additionally have sponge or swellable material disposed within the lumen of the proximal tubular section 410a and / or the distal tubular section 440b.

[0131] The membrane 330 may not be integral with the flexible tubular sleeve section 410a, 410b but may be separate and made from a different material from the tubular sleeve section 410a, 410b. The membrane 430 may be attached to the flexible tubular sleeve sections 410a, 410b, for example, with an adhesive, a mechanical connection or with an ultrasonic weld.

[0132] The medical implants 100, 200, 300, 400 may not have a sacrificial layer 150, 250, 350, 450.

[0133] The fluid blocking portion is not limited to only membranes and sponge or swellable materials but may include any element which can at least partially blocking the flow of fluid through the lumen of the flexible sleeve . For example , the fluid blocking portion may include , for example , coils , meshes or bristles .

[0134] All of the above are fully within the scope of the present disclosure and are considered to form the basis for alternative embodiments in which one or more combinations of the above-described features are applied, without limitation to the speci fic combination disclosed above .

[0135] The terms " generally, " " substantially, " " about , " or " approximately" are meant to mean as close to the corresponding condition as reasonably possible , and typically not varying from it by more than 10% , unless circumstances indicate otherwise . Any species element of a genus element can have the characteristics or elements of any other species element of that genus . The term " comprising" is not meant to be limiting . The above-described configurations , elements or complete assemblies and methods and their elements for carrying out the invention, and variations of aspects of the invention can be combined and modi fied with each other in any combination .

[0136] In light of this , there will be many alternatives which implement the teaching of the present disclosure . It is expected that one skilled in the art will be able to modi fy and adapt the above disclosure to suit its own circumstances and requirements within the scope of the present disclosure , while retaining some or all technical ef fects of the same , either disclosed or derivable from the above , in light of his common general knowledge in this art . All such equivalents , modi fications or adaptations fall within the scope of the present disclosure .

Claims

Claims1 . A medical implant for blocking or restricting a flow of fluid through a vessel , the medical implant comprising : a flexible tubular sleeve having a lumen and defining a longitudinal axis , the flexible tubular sleeve having a radially expanded configuration and a radially contracted configuration; a fluid blocking portion for at least partially blocking the flow of fluid through the lumen; and an adhesive layer disposed on a radial outside surface of the flexible tubular sleeve for bonding to a wall of the vessel .2 . The medical implant of claim 1 , wherein the flexible tubular sleeve is substantially tubular in the radially expanded configuration and the radially contracted configuration .3 . The medical implant of claim 1 or 2 , wherein the flexible tubular sleeve is configured to be disposed over an expandable balloon .4 . The medical implant of any of claims 1 , 2 or 3 wherein the fluid blocking portion is positioned at one end of the flexible tubular sleeve .5 . The medical implant of claim 4 , wherein the fluid blocking portion comprises a fluid-proof membrane .6 . The medical implant of claim 5 , wherein the fluid-proof membrane is integral with the flexible tubular sleeve .7 . The medical implant of any preceding claim, wherein the flexible tubular sleeve is made from a biodegradable material .8 . The medical implant of any preceding claim, wherein the flexible tubular sleeve comprises a collagen film or a polymer film .9 . The medical implant of any preceding claim, wherein the outside surface of the flexible tubular sleeve comprises ribs , ridges or bumps .10 . The medical implant of any preceding claim, wherein the outside surface of the flexible tubular sleeve comprises a plurality of ribs which are circumferentially disposed around the flexible tubular sleeve .11 . The medical device of any preceding claim, further comprising a stent disposed within the flexible tubular sleeve .12 . The medical device of claim 11 , wherein the stent is fixed to an inner surface of the flexible tubular sleeve .13 . The medical device of claim 11 or 12 , wherein the flexible tubular sleeve is a first flexible tubular sleeve , further comprising a second flexible tubular sleeve and wherein the stent is disposed between the first flexible tubular sleeve and the second flexible tubular sleeve .14 . The medical device of claim 11 , 12 or 13 , wherein the stent is a sel f-expanding stent .15 . The medical device of any of claims 11 to 14 , wherein the stent is at least partially made from a shape-memory material .16 . The medical implant of any of claims 11 to 15 , wherein the stent comprises at least one of nitinol , stainless steel , a cobalt-chromium alloy, magnesium, a polymer or a bioresorbable polymer .17 . The medical implant of any preceding claim, wherein the fluid blocking portion is positioned within the lumen of the flexible tubular sleeve and comprises a sponge material or swellable material for blocking fluid flow through the lumen of the flexible tubular sleeve .18 . The medical implant of claim 17 , wherein the sponge material or swellable material comprises one or more of : a swellable hydrogel , non-moisture curing adhesive , collagen, or nanosilicate .19 . The medical implant of claim 17 or 18 , wherein the sponge material or swellable material comprises a thrombogenic material .20 . The medical implant of any preceding claim, wherein the adhesive layer comprises one or more of : microbial transglutaminase (mTG) , gelatin, cyanoacrylate , a lysine- based adhesive , a fibrin-based adhesive , polyvinylpyrollidone , or a N-hydroxy-succinimide-activated synthetic polymer .21 . The medical implant of any preceding claim, wherein the adhesive layer comprises microbial transglutaminase (mTG) and gelatin .22 . The medical implant of any preceding claim, wherein the adhesive layer covers at least 50% of the outer surface of the flexible tubular sleeve .23 . The medical implant of any preceding claim, further comprising a sacri ficial layer disposed over the adhesive layer .24 . The medical implant of claim 23 , wherein the sacri ficial layer comprises one or more of : polyvinyl alcohol ,polyacrylic acid, polyethylene glycol , polyvinyl pyrrolidone , polyacrylamide , N- ( 2-hydroxypropyl ) methacrylamide , polyoxazolines , polyphosphoesters , polyphosphazenes , pectins , dextrans , hyaluronic acid, chitosan derivatives , carrageenan, cellulose or modi fied cellulose , starch or starch derivatives , or combinations thereof .25 . The medical implant of claim 23 or 24 , wherein the sacri ficial layer is configured to dissolve when the flexible tubular sleeve is introduced into a vessel .26 . The medical implant of any of claims 23 to 25 , wherein the sacri ficial layer is configured to break away when the flexible tubular sleeve expands from the collapsed configuration to the expanded configuration .27 . The medical implant of any preceding claim, wherein the outside surface of the flexible tubular sleeve has been surface treated by one or more of : chemical treatment with primers , laser treatment , UV radiation, and plasma treatment via addition, creation, and / or exposure of surface groups including at least one of reactive oxygen or nitrogen species .28 . The medical implant of any preceding claim, wherein the flexible tubular sleeve comprises a proximal tubular section and a distal tubular section and the fluid blocking portion is positioned between the proximal tubular section and the distal tubular section .29 . The medical implant of claim 28 , wherein the fluid blocking portion comprises a membrane forming a longitudinal section with a reduced lumen compared to the flexible tubular sleeve .30 . The medical implant of claim 29 , wherein the fluid blocking portion comprises a membrane forming a longitudinalsection with a closed lumen to prevent fluid flow through the flexible tubular sleeve .31 . The medical implant of claim 28 to 30 , further comprising a first stent section positioned within the proximal tubular section and a second stent section positioned within the distal tubular section and wherein the first stent section and the second stent section are not connected .32 . A medical device for sealing a vessel , the medical device comprising : a catheter shaft defining a longitudinal axis ; an expandable balloon positioned at a distal end of the catheter shaft , the expandable balloon having a radially contracted configuration and a radially expanded configuration; and the medical implant of any of claims 1 to 25 .33 . The medical device of claim 32 , wherein the balloon comprises a cylindrical barrel portion .34 . The medical device of claim 33 , wherein the flexible tubular sleeve is disposed at least over the cylindrical barrel portion of the balloon .35 . The medical device of claim 34 , wherein at least the portion of the outer surface of the flexible tubular sleeve disposed over the cylindrical barrel portion of the balloon is coated with the adhesive layer .36 . The medical device of any of claims 32 to 35 , wherein the catheter shaft has an inflation lumen in fluid connection with the balloon .37 . A method of blocking or restricting a flow of fluid through a vessel , the method comprising :inserting a medical implant having a flexible tubular sleeve into a vessel in a radially contracted configuration, the flexible tubular sleeve adapted to expand from the radially contracted configuration to a radially expanded configuration; bonding a radial outside surface of the flexible tubular sleeve to a wall of the vessel with an adhesive layer ; at least partially blocking the flow of fluid through a lumen of the medical implant with a fluid blocking portion .38 . The method of claim 37 , wherein expanding the flexible tubular sleeve from the radially contracted configuration to the radially expanded configuration comprises disposing the flexible tubular sleeve over a balloon and inflating the balloon .39 . The method of claim 37 , wherein expanding the flexible tubular sleeve from the radially contracted configuration to the radially expanded configuration comprises expanding a stent disposed within the flexible tubular sleeve .40 . The method of claims 37 to 39 , wherein the fluid blocking portion comprises one or more of a membrane , a sponge material or a swellable material .41 . A method blocking or restricting a flow of fluid through a blood vessel , the method comprising : bonding a flexible tubular sleeve having a lumen to a wall of the blood vessel ; and at least partially blocking the flow of fluid through the lumen of the flexible tubular sleeve with a barrier .42 . A medical implant for blocking or restricting a flow of fluid through a vessel , the medical implant comprising : a flexible tubular sleeve having a lumen and defining a longitudinal axis , the flexible tubular sleeve having aradially expanded configuration and a radially contracted configuration; a restrictor or barrier associated with the flexible tubular sleeve for at least partially blocking the flow of fluid through the lumen; and an adhesive layer disposed on a radial outside surface of the flexible tubular sleeve for bonding to a wall of the vessel .

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