TISSUE CLOSURE DEVICE
FIELD
[01] The present invention relates to a tissue closure device, in particular to a vascular closure device, such as a blood vessel closure device, even more to a large bore vascular closure device. In particular, the present invention relates to methods and devices for closing and/or sealing punctures in tissue, such as in blood vessels.
BACKGROUND
[02] In percutaneous medical procedures, an opening may be created in a wall of a blood vessel to allow for the insertion of various medical devices which can be navigated through the blood vessel to a site to be treated. For example, after initial access into the blood vessel is obtained, a medical device may be inserted through the tissue tract created between the skin, or epidermis, of the patient down through the subcutaneous tissue and into the opening formed in the blood vessel. The medical device may then be navigated through the blood vessel to the treatment site.
[03] Once the procedure is completed, the medical device(s) or other equipment introduced into the blood vessel may be retracted from the body through the blood vessel, out the opening in the wall of the blood vessel, and out through the tissue tract. The physician or other medical technician is presented with the challenge of trying to close the opening in the blood vessel and/or the tissue tract formed in the epidermis and subcutaneous tissue. A number of different device structures, assemblies, and methods are known for closing the opening in the blood vessel and/or tissue tract, each having certain advantages and disadvantages. There is an ongoing need to provide alternative medical devices as well as alternative methods for manufacturing and/or using medical devices.
SUMMARY
[04] According to a first aspect of the present invention there is provided a device for sealing an opening in a tissue, such as a blood vessel, the device comprising: a shaft, the shaft operable, in use, to extend through the opening in the tissue; wherein the shaft comprises an expandable support portion, the expandable support portion being operable, in use, to extend radially outward from the shaft to provide a surface which prevents or reduces inversion of the tissue, such as reduces inversion of the blood vessel wall into the vessel lumen; a sheath slidably disposed over the shaft, the sheath having a split distal portion; and a plurality of anchoring portions on at least two sections of the split distal portion of the sheath, the anchoring portions being operable, in use, to engage the tissue, such as the tissue of the blood vessel wall, by at least partially penetrating the tissue.
[05] The device is for sealing an opening in a tissue. The tissue may be any suitable tissue. Suitably, the tissue may be a blood vessel. For example, the tissue may be an artery or a vein. The tissue may therefore comprise the tissue and a lumen into which the device may be inserted (i.e., via the opening in the tissue). It will be appreciated by a person skilled in the art that when the tissue is a blood vessel, the device should be of sufficient proportions to allow it to be inserted into the lumen of the tissue without causing (further) damage thereto.
[06] The device comprises a shaft. The shaft is operable, in use, to extend through an opening in a tissue, such as an opening in a blood vessel.
[07] The shaft suitably has a longitudinal axis. The longitudinal axis suitably extends along the length of the shaft from a proximal end to a distal end. As such, the shaft may suitably comprise a distal end and a proximal end. Relative terms such as "proximal", "distal", and the like, will be well known to a person skilled in the art and are to be generally considered with respect to the positioning, direction, and/or operation of elements of the device relative to the user of the device. For example, "proximal" generally refers to elements of the device, and/or portions thereof, which are closer to the user. For example, "distal" generally refers to elements of the device, and/or portions thereof, which are farther from the user. However, it will be understood by a person skilled in the art that the terms "proximal" and "distal" may be arbitrarily assigned in order to facilitate understanding of the invention.
[08] The distal end of the shaft may have any suitable shape. Suitably, the distal end of the shaft may be concave shaped. Suitably, the distal end of the shaft may be concave shaped so that it may engage an outer surface of the tissue. Advantageously, the use of a shaft having a concave distal end means that (further) damage to the tissue may be reduced or avoided.
[09] The shaft may be any suitable length (from the proximal end to the distal end). The shaft may be at least 10 cm in length, such as at least 11 , 12, 13, 14, 15, 16, 17, 19 or even 20 cm in length. The shaft may be up to 50 cm in length, such as up to 45, 40, 35, 30 or even 25 cm in length. The shaft may be from 10 to 50 cm in length, such as from 15 to 40 cm in length, such as from 20 to 30 cm in length, or even from 20 to 25 cm in length.
[10] Suitably, the shaft may be cylindrical. The shaft may have any suitable diameter. The shaft may have a diameter of up to 20 mm, such as up to 19, 18, 17, 16, 15, 14, 13, 12 or even 11 mm. the shaft may have a diameter of at least 2 mm, such as at least 3, 4, 5, 6, 7, 8, 9 or even 10 mm. The shaft may have a diameter of from 2 to 20 mm, such as from 3 to 15 mm, such as from 5 to 12 mm, or even from 8 to 12 mm. [11] Suitably, the shaft may comprise an outer wall. Suitably, the outer wall of the shaft may define a lumen. The lumen, when present, may suitably extend through the shaft from a proximal end to a distal end along the longitudinal axis of the shaft. The lumen, when present, may have any suitable diameter. The lumen, when present, may have a diameter up to 18 mm, such as up to 17, 16, 15, 14, 13, 12, 1 1 or even 10 mm. The lumen may have a diameter of at least 1 mm, such as at least 2, 3, 4, 5, 6, 7, 8, or even 9 mm. The shaft may have a diameter of from 1 to 18 mm, such as from 3 to 15 mm, such as from 5 to 12 mm, such as from 8 to 12 mm, or even from 9 to 11 mm. Advantageously, the presence of a lumen extending through the shaft from a proximal end to a distal end along the longitudinal axis of the shaft, may mean that a guide wire can be slidably disposed within the lumen.
[12] As such, suitably, the device may further comprise a guide wire. Suitably, the guide wire may be configured to be slidably disposed within the lumen of the shaft.
[13] Alternatively or additionally, the device may further comprise a hypodermic tube (also known as a “hypotube”). Suitably, the hypodermic tube may be configured to be slidably disposed within the lumen of the shaft. Suitably, the hypodermic tube may be operable, in use, to indicate the proximity of the device from the vessel wall, in use.
[14] Alternatively or additionally, the device may further comprise a percutaneous medical device. Suitably, the percutaneous medical device may be configured to be slidably disposed within the lumen of the shaft. For example, a percutaneous medical device may be slidably disposed within the lumen of the shaft such that a medical procedure, such as an intravascular procedure, may be performed at a site of interest. Examples of suitable percutaneous medical devices include, but are not limited to: a catheter, a trocar, a dilator, an endoscope, a delivery device, such as a delivery device comprising a catheter and a medical implant (e.g., a stent, a filer device, a replacement heart valve, etc.), an implant, and combinations thereof.
[15] The shaft may be formed from any suitable material. The shaft may be formed from a metal, a metal alloy, a polymer, a metal-polymer composite, ceramics, and/or combinations thereof.
[16] Examples of suitable metals and metal alloys include, but are not limited to, stainless steel, such as 444V, 444L, and 314LV stainless steel; mild steel; nickel-titanium alloys, such as linear- elastic and/or super-elastic nitinol; nickel-chromium-molybdenum alloys; nickel-copper alloys; nickel-cobalt-chromium-molybdenum alloys; nickel-molybdenum alloys; nickel-chromium alloys; nickel-molybdenum alloys; nickel-cobalt alloys; nickel-iron alloys; nickel-tungsten; tungsten alloys; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys; platinum enriched stainless steel; titanium; combinations thereof; and combinations thereof.
[17] Examples of suitable nickel-chromium-molybdenum alloys include, but are not limited to: UNS: N06625, such as those sold under the tradename INCONEL®, for example INCONEL® 625; UNS: N06022, such as those sold under the tradename HASTELLOY®, for example HASTELLOY® C-22®; UNS: NI0276, such as those sold under the tradename HASTELLOY®, for example HASTELLOY®C276®; and combinations thereof.
[18] Examples of suitable nickel-copper alloys include, but are not limited to: UNS N04400, such as those sold under the tradename MONEL®, for example MONEL® 400, those sold under the tradename NICKEL V AC®, for example NICKEL V AC® 400, those sold under the tradename NICORROS®, for example NICORROS® 400; and combinations thereof.
[19] Examples of suitable nickel-cobalt-chromium-molybdenum alloys include, but are not limited to: UNS: R44035, such as those sold under the tradename MP35-N®; and combinations thereof.
[20] Examples of suitable nickel-molybdenum alloys include, but are not limited to: UNS: NI0665, such as those sold under the tradename HASTELLOY®, for example HASTELLOY® ALLOY B2®; and combinations thereof.
[21] Examples of suitable cobalt-chromium-molybdenum alloys include, but are not limited to, UNS: R44003, such as those sold under the tradenames ELGILOY® and/or PHYNOX®; and combinations thereof.
[22] Examples of suitable polymers include, but are not limited to, polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, for example, those sold under the tradename DELRIN® commercially available from DuPont), polyether block ester, polyurethane (for example, those sold under the tradename Polyurethane 85A), polypropylene (PP), polyvinylchloride (PVC), polyether-ester (for example, those sold under the tradename ARNITEL® commercially available from DSM Engineering Plastics), ether or ester based copolymers (for example, butylene/poly(alkylene ether) phthalate and/or other polyester elastomers such as those sold under the tradename HYTREL® commercially available from DuPont), polyamide (for example, those sold under the tradename DURETHAN® commercially available from Bayer or those sold under the tradename CRISTAMID® commercially available from Elf Atochem), elastomeric polyamides, block polyamide/ethers, polyether block amide (PEBA, for example those available under the trade name PEBAX®), ethylene vinyl acetate copolymers (EV A), silicones, polyethylene (PE), Marl ex high-density polyethylene, Marl ex low- density polyethylene, linear low density polyethylene (for example those sold under the tradename REXELL®), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), poly paraphenylene terephthalamide (for example, those sold under the tradename KEVLAR®), polysulfone, nylon, nylon-12 (such as those sold under the tradename GRILAMID® commercially available from EMS American Grilon), perfluoro(propyl vinyl ether) (PF A), ethylene vinyl alcohol, poly olefin, polystyrene, epoxy, polyvinylidene chloride (PV dC), poly(styrene-b-isobutylene-b-styrene) (for example, SIBS and/or SIBS 50A), polycarbonates, ionomers, biocompatible polymers, copolymers of any of the aforementioned polymers, polymer/metal composites, and combinations thereof.
[23] Suitably, the shaft may comprise a liquid crystal polymer (LCP). For example, the shaft may be formed from a blend of one or more material(s) including a liquid crystal polymer (LCP), such as a blend of one or more material(s) comprising up to 6 weight percent LCP based on the total weight of the blend.
[24] Suitably, the shaft may be formed from a nickel-titanium alloy, such as nitinol. The nickeltitanium may comprise linear-elastic and/or super-elastic nitinol. "Linear elastic" (or "non-super- elastic") nitinol is similar in chemistry to conventional shape memory and super elastic varieties, but may exhibit distinct and useful mechanical properties. Linear elastic nitinol may be distinguished from super elastic nitinol in that the linear elastic does not display a substantial "super-elastic plateau" or "flag region" in its stress/strain curve like super elastic nitinol does. Instead, in the linear elastic nitinol, as recoverable strain increases, the stress continues to increase in a substantially linear, or a somewhat, but not necessarily entirely linear relationship until plastic deformation begins or at least in a relationship that is more linear than the super elastic plateau and/or flag region that may be seen with super elastic nitinol. Thus, as used herein, the term “linear elastic” nitinol includes "substantially" linear elastic nitinol (and the terms may be used interchangeably herein).
[25] Linear elastic nitinol may also be distinguishable from super elastic nitinol in that linear elastic nitinol may accept up to about 2-5% strain while remaining substantially elastic (e.g., before plastically deforming) whereas super elastic nitinol may accept up to about 8% strain before plastically deforming. This is in contrast to stainless steel, for example, which may accept only about 0.2 to 0.44% strain before plastically deforming.
[26] Suitably, the linear elastic nickel-titanium alloy is an alloy that does not show any martensite/austenite phase changes that are detectable by differential scanning calorimetry (DSC) and dynamic metal thermal analysis (DMTA) over a large temperature range. For example, there may be no martensite/austenite phase changes detectable by DSC and DMTA analysis in the range of about -60 degrees Celsius (°C) to about 120 °C in the linear elastic nickel-titanium alloy. The mechanical bending properties of such material may therefore be generally inert to the effect of temperature over this very broad range. Suitably, the mechanical bending properties of the linear elastic nickel-titanium alloy at ambient or room temperature may be substantially the same as the mechanical properties at body temperature, for example, in that they do not display a super-elastic plateau and/or flag region. In other words, across a broad temperature range, the linear elastic nickel-titanium alloy may maintain its linear elastic characteristics and/or properties.
[27] The linear elastic nickel-titanium alloy may have any suitable composition. For example, the linear elastic nickel-titanium alloy may comprise from 50 to 60 weight percent, such as from 54 to 57 weight percent, nickel based on the total weight of the alloy. Suitably, the remainder may essentially comprise titanium. For example, the linear elastic nickel-titanium alloy may comprise from 50 to 40 weight percent, such as from 46 to 43 weight percent, titanium based on the total weight of the alloy Examples of suitable nickel-titanium alloys include, but are not limited to: FHP- NT alloy commercially available from Furukawa Techno Material Co. of Kanagawa, Japan; those sold under the trade mane ULTANIUM™ commercially available from Neo-Metrics; those sold under the tradename GUM METAL™ commercially available from Toyota; and combinations thereof.
[28] Suitably, the shaft may be formed from a super-elastic alloy, for example a super-elastic nitinol. A super-elastic alloy, for example a super-elastic nitinol, may be used to achieve one or more desired properties.
[29] Suitably, the shaft may comprise a radiopaque material. For example, the shaft may be doped with, formed from, or otherwise include a radiopaque material. It is well known to a person skilled in the art that radiopaque materials are materials capable of producing a relatively bright image on a fluoroscopy screen or another imaging technique during a medical procedure. Advantageously, therefore, the use of a radiopaque material may aid a user in determining the location of the shaft and/or device. Examples of suitable radiopaque materials include, but are not limited to: gold, platinum, palladium, tantalum, tungsten alloy, polymer materials loaded with a radiopaque filler, and combinations thereof.
[30] Suitably, the shaft may comprise a material that does not substantially distort an MRI image, for example which does not create substantial artifacts (e.g., gaps in the image). For example, the shaft may not comprise, i.e., may be substantially free of, ferromagnetic materials (which may create artifacts in an MRI image). Suitably, the shaft may be made from a material that an MRI machine can image. Example of suitable materials that exhibit such characteristics include, but are not limited to: tungsten, cobalt-chromium-molybdenum alloys, nickel- cobalt-chromium-molybdenum alloys, nitinol, and combinations thereof.
[31] The shaft comprises an expandable support portion. The expandable support portion may be located at any suitable position on the shaft. Suitably, the expandable support portion may be located proximate to the distal end of the shaft. Advantageously, when the expandable support portion is located proximate to the distal end of the shaft, the device may be deployed perpendicularly to the axis of a blood vessel, for example. For example, when the expandable support portion is located proximate to the distal end of the shaft, the expandable support portion may be caused to extend radially even when the device is perpendicular to the axis of a blood vessel, for example. As such, it will be appreciated that the distance from the expandable support portion to the distal tip of the shaft should suitably not exceed the diameter of the blood vessel, for example. [32] The expandable support portion is operable, in use, to extended radially outward from the shaft. For example, the shaft may be operable, in use, to extend radially outward from the outer surface of the shaft.
[33] Suitably, the expandable support portion may be operable, in use, to move from a first configuration to a second configuration. Suitably, the diameter of the expandable support portion in the first configuration may be less than the diameter of the expandable support portion in the second configuration. Suitably, the diameter of the expandable support portion in the first configuration may be less than the diameter of the opening in the tissue. Advantageously, by having a diameter that that is less than the diameter of the opening in the tissue in the first configuration, the shaft, including the expandable support portion, may be inserted into and through the opening in the tissue without (further) damaging the tissue.
[34] Suitably, the expandable support portion may be substantially the same diameter as the shaft in the first configuration. For example, the expandable support portion may lie substantially flat against the outer surface of the shaft in the first configuration.
[35] Suitably, the expandable support portion may extend radially outward from the shaft in the second configuration. For example, the expandable support portion may extend radially outward from the longitudinal axis of the shaft in the second configuration. For example, the expandable support portion may extend radially outward from the outer surface of the shaft in the second configuration. Suitably, the expandable portion may extend radially outward such that the surface provided by the expandable portion is substantially perpendicular to the longitudinal axis of the shaft in the second configuration. Suitably, the expandable portion may extend radially outward such that the surface provided by the expandable portion is substantially perpendicular to the outer surface of the shaft in the second configuration.
[36] When extended radially outward the diameter of the expandable support portion should suitably exceed the size of the opening in the tissue, i.e., should suitably be largerthan the longest distance of the opening in the tissue.
[37] The expandable support portion is operable, in use, to extend radially outward from the shaft to provide a surface which prevents or reduces inversion of the tissue. Suitably, the expendable support portion may be operable to provide a surface which prevents or reduces inversion of the tissue in the second configuration. For example, when the expandable support portion is extended radially outward from the shaft, partial withdrawal of the shaft from the opening in the tissue may cause eversion of the tissue. Advantageously, when the tissue is a blood vessel, for example, the provision of an expandable support portion operable to provide a surface which prevents or reduces inversion of the tissue means that there may be a reduced likelihood of tissue remaining present in the lumen of the blood vessel, i.e., of there being inverted tissue remaining in the lumen of the blood vessel, upon closure of the opening in the tissue. This may reduce the likelihood of blockages etc., in the blood vessel following closure of the opening. Further, it may reduce the risk of acute thrombosis/clot formation. It is known that the outer wall (or adventitia) of a blood vessel is thrombogenic and promotes clot formation, as such it is important to keep the adventitia out of the blood vessel lumen.
[38] The expandable support portion may have any suitable form. For example, the expandable support portion may be integrally formed with the shaft or may be attached to the shaft. When the expandable support portion is attached to the shaft, the expandable support portion may be attached to an outer surface of the shaft.
[39] The expandable support portion may comprise an o-ring, an inflatable annular balloon, an expandable flange, or other expandable structure disposed on and/or about an outer surface of the shaft.
[40] Suitably, the expandable support portion may comprise an expandable flange. Suitably, the expandable support portion may comprise an expandable flange in the form of a segmented portion. Suitably, each segment of the segmented portion may be operable to lie substantially parallel to the longitudinal axis of the shaft in the first configuration (as defined herein). For example, each segment of the segmented portion may be operable to lie substantially flat against the outer surface of the shaft in the first configuration (as defined herein). Suitably, each segment of the segmented portion may be operable to extend radially outward in the second configuration (as defined herein). For example, each segment of the segmented portion may comprise two sections, each section of a segment being operable to fold against one another, and lie substantially flat against one another, in the second configuration.
[41] The segmented portion may be formed from any suitable material. The segmented portion may be formed from a metal, such as any of the metals defined herein. Suitably, the segmented portion may be formed from a nickel-titanium alloy, such as nitinol. Advantageously, the use of nitinol, or similar materials, means that each segment of the segmented portion is able to “spring” back to the first configuration, i.e., so as to lie substantially flat against the outer surface of the shaft, after un-deployment from the second configuration.
[42] The expandable support portion may be caused to extend radially outward from the shaft by any suitable means. For example, the expandable support portion may be caused to move from the first configuration to the second configuration by any suitable means (wherein the first and second configurations are as defined herein). For example, the expandable support portion may be caused to move from the second configuration to the first configuration by any suitable means (wherein the first and second configurations are as defined herein). Suitably, the device may further comprise a first actuator. Suitably, the first actuator may be operable to cause the expandable support portion to extend radially outward from the shaft and vice versa. For example, the first actuator may be operable to move the expandable support portion between the first configuration and the second configuration (wherein the first and second configurations are as defined herein). [43] The first actuator may be electronic and/or mechanical. Suitably, the first actuator may be mechanical. The first actuator may comprise a button or the like, which when actuated by a user causes the expandable support portion to extend radially outward from the shaft and/or vice versa.
[44] The device comprises a sheath. The sheath is slidably disposed over the shaft. Suitably, the sheath may comprise an outer wall which defines a lumen. Suitably, the lumen extends through the sheath from a proximal end to a distal end along a longitudinal axis of the sheath. The lumen of the sheath may have any suitable diameter. It will be appreciated by a person skilled in the art that the diameter of the lumen of the sheath should suitably be such that the shaft may be disposed therein, i.e., the diameter of the lumen of the sheath should be greater than the diameter of the shaft.
[45] The sheath has a split distal portion.
[46] The split distal portion may comprise any suitable number of split sections. Suitably, the split distal portion may comprise at least 2, such as at least 3, such as at least 4 split sections. Suitably, the split distal portion may comprise 2 split sections. For the avoidance of doubt, reference herein to “split sections” is used interchangeably with “sections” when describing the split distal portion.
[47] Suitably, the split distal portion of the sheath may be operable, in use, to move from a first configuration to a second configuration. In the first configuration, each section of the split distal portion may be forced radially outward. For example, each section of the split distal portion may be forced radially outward by the shaft. Suitably, each section of the split distal portion may be forced radially outward when the sheath is disposed over the shaft. In the second configuration, each section of the split distal portion may be forced radially inwards. For example, each section of the split distal portion may be forced radially inwards by an outer carriage (as defined herein) or by any other suitable means. As such, the split distal portion of the sheath may be operable, in use, to move from a more open configuration to a more closed configuration, wherein “more open” means that the diameter of the split distal portion is greater than the diameter of the split distal portion in a “more closed” configuration. The split distal portion may maintain a substantially central position when no force is applied. By “central position” in this context, is meant that each section of the split distal portion of the sheath is neither forced radially outward nor radially inward. For example, in the central position each section of the split distal portion may lie in the position to which they are naturally biased (i.e., without the application of any force). For example, in the central position the diameter of the split distal portion of the sheath may be substantially equal to the diameter of the sheath.
[48] Suitably, the diameter of the split distal portion of the sheath in the first configuration may be greater than the diameter of the split distal portion of the sheath in the second configuration. Suitably, the diameter of the split distal portion of the sheath may be greater than the diameter of the proximal end of the sheath when each section of the split distal portion is forced radially outward, for example, in the first configuration. Suitably, the diameter of the split distal portion of the sheath may be less than the diameter of the proximal end of the sheath when each section of the split distal portion is forced radially inward, for example, in the second configuration. Suitably, the diameter of the split distal portion of the sheath may be substantially closed in the second configuration. By “substantially closed” in this context, is meant that the diameter of the split distal portion is sufficiently small to allow, or cause, the anchoring portions, which are located on two or more of the sections of the split distal portion and which are operable to engage with the tissue in use, to bring the tissue around the opening of the tissue together.
[49] In use, the anchoring portions may engage with the tissue when the split distal portion is in the first configuration or in the central position. Suitably, the anchoring portions may engage with the tissue when the split distal portion of the sheath is in a more open configuration, i.e., can be moved radially inwards. Preferably, the split distal portion may be in the central position when the anchoring portions engage with the tissue. Advantageously, the central position of the split distal portion allows the anchoring portions to be substantially perpendicular to the wall of the tissue being engaged allowing for maximum engagement of the anchoring portions to the tissue and minimum (further) damage to the tissue.
[50] As such, in use, movement of each section of the split distal portion of the sheath inwards from the radially outward position to the radially inward position, causes the anchoring portions to move the tissue inwards from the outer edge of the opening in the tissue, such that the opening in the tissue becomes substantially closed.
[51] The sheath may be formed from any suitable material. The sheath may be formed from a metal, a metal alloy, a polymer, a metal-polymer composite and/or a ceramic. Suitable examples of each of a metal, a metal alloy, a polymer, a metal-polymer composite and a ceramic are as provided herein in relation to the shaft. Suitably, the distal portion of the sheath may be formed from a material which is sufficiently flexible to permit bending or flexing of the sections of the split distal portion from the first configuration, i.e., wherein sections of the split distal portion are forced radially outward, to the second configuration, i.e., wherein sections of the split distal portion are forced radially inward.
[52] The split distal portion of the sheath may be caused to adopt the first configuration by any suitable means (wherein the first configuration is as defined herein). It will be appreciated by a person skilled in the art that each section of the split distal portion of the sheath will naturally, i.e., in the absence of any external factors/forces, adopt a central position. As such, it may be necessary to force each section of the split distal portion radially inwards, i.e., to the second configuration (wherein the second configuration is as defined herein). As such, it may be necessary to force each section of the split distal portion radially outwards, i.e., into the first configuration. Any suitable means may be used to force each section of the split distal portion radially outward. Suitably, each section of the split distal portion may be forced radially outward by the shaft, such as by the sheath being slidably disposed on the shaft. Suitably, movement, such as by sliding, of the shaft through the lumen of the sheath causes each section of the split distal portion to move radially outward. As such, suitably, the shaft may have a sufficient diameter to force, for example to push, each section of the split distal portion radially outward.
[53] The split distal portion of the sheath may be caused to move from the first configuration to the second configuration by any suitable means (wherein the first and second configurations are as defined herein). Suitably, each section of the split distal portion may be caused to move partially radially inwards, i.e., from the position in the first configuration, by removal of the shaft. Suitably, each section of the split distal portion may be caused to move further, or substantially fully, radially inwards by an outer carriage (as defined herein) or any other suitable means.
[54] Suitably, the device may further comprise an outer carriage slidably disposed over the sheath. Suitably, the outer carriage may be operable to cause the sections of the split distal portion of the sheath to move radially inward, i.e., to the second configuration. For example, in use, the outer carriage may be pushed downwards from the proximal end of the sheath toward the split distal portion of the sheath, manually by a user, by mechanical means, by electronic means, or otherwise, causing the outer carriage to push down against the sections of the split distal portion of the sheath and, in doing so, cause the sections of the split distal end to move inwards. Suitably, the outer carriage may be used to cause each section of the split distal portion of the sheath to move further radially inwards following removal of the shaft.
[55] The outer carriage suitably comprises a lumen, such that the outer carriage may be slidably disposed over the sheath. The lumen of the outer carriage may have any suitable diameter. It will be appreciated by a person skilled in the art that the diameter of the lumen of the outer carriage should suitably be such that the sheath may be disposed therein, i.e., the diameter of the lumen of the outer carriage should be greater than the diameter of the sheath. However, it will also be appreciated by a person skilled in the art that the lumen of the outer carriage may suitably be such that it is able to force each section of the split distal portion of the sheath radially inward.
[56] The outer carriage may be formed from any suitable material. For example, the outer carriage may be formed from a metal, a metal alloy, a polymer, a metal-polymer composite and/or a ceramic. Suitable examples of each of a metal, a metal alloy, a polymer, a metal-polymer composite and a ceramic are as provided herein in relation to the shaft.
[57] Suitably, the device may further comprise a second actuator. Suitably, the second actuator may be operable to cause the sections of the split distal portion of the sheath to move from the first configuration to the second configuration and vice versa. For example, the second actuator may be operable to cause the outer carriage to move, such as to slidably move, up and down the sheath, i.e., from the proximal end to the distal end of the sheath and vice versa.
[58] The second actuator may be electronic and/or mechanical. Suitably, the second actuator may be mechanical. The second actuator may comprise a button or the like, which when actuated by a user causes the outer carriage to move, such as to slidably move, up and down the sheath, i.e., from the proximal end to the distal end of the sheath and vice versa.
[59] The device comprises a plurality of anchoring portions. The anchoring portions are located on at least two sections of the split distal portion of the sheath. The anchoring portions may each individually be located at any suitable position on the sections of the split distal portion. Suitably, the anchoring portions may each individually be located at the distal end of each section of the split distal portion. It will be appreciated by a person skilled in the art that the anchoring portions should be located at a position wherein they are able to engage the tissue by at least partially penetrating the tissue.
[60] The device may comprise any suitable number of anchoring portions. The device may comprise at least 2, such as at least 3, such as at least 4 anchoring portions. The device may comprise 4 anchoring portions. Suitably, the device may comprise at least 2, such as 2, anchoring portions per section of the split distal portion (for example, if the split distal portion comprises 2 sections, the device may suitably comprise 4 anchoring portions, etc.). However, it is within the scope of the invention that each section of the split distal portion of the sheath may individually comprise one anchoring portion.
[61] As described herein, the anchoring portions are located on at least two sections of the split distal portion of the sheath. Suitably, the anchoring portion are located on two sections of the split distal portion. Suitably, the anchoring portions may be located at on least two, such as on two, opposing sections of the split distal portion of the sheath. Advantageously, by locating the anchoring portions on at least two, such as on two, opposing sections of the split distal portion of the sheath, the anchoring portions are able, in use, to move the tissue inwards from the outer edge of the opening in the tissue, such that the opening in the tissue becomes substantially closed, upon movement of the opposing sections of the split distal portion of the sheath inwards from the radially outward position and/or central position.
[62] Suitably, each section of the split distal portion of the sheath comprises at least one, such as at least two, such as two anchoring portions.
[63] Each anchoring portion may have any suitable form. Suitably, each anchoring portion may comprise a needle. Each needle may be formed from any suitable material. It will be appreciated by a person skilled in the art that each needle should suitably be formed from a material that has sufficient strengthen to penetrate the tissue without breaking and/or deforming. For example, each needle may be formed from a metal, metal alloy or a combination thereof. Examples of suitable metals or metal alloys are as defined herein in relation to the shaft. Suitably, each needle may be formed from stainless steel.
[64] Each anchoring portion may individually be retractable. For example, one, more than one, or all of the anchoring portions present on the device may be retractable. For example, all of the anchoring portions present on the device may be retractable. Advantageously, the use of retractable anchoring portion may mean that the device can be inserted into and/or removed from the lumen of the tissue without causing (further) damage thereto.
[65] The anchoring portions are operable, in use, to engage the tissue by at least partially penetrating the tissue. Suitably, the anchoring portions may be operable, in use, to fully penetrate the tissue. By “fully penetrate” is meant that the anchoring portions are operable to pierce the tissue and extend the full distance therethrough, such that the distal end of the anchoring portions emerges on the other side of the tissue (for example, when the tissue is a blood vessel, into the lumen of the blood vessel).
[66] In use, upon engagement of the tissue the anchoring portions may be caused to move inwards. As described herein, the anchoring portions are located on at least two sections, such as on two sections, of the split distal portion of the sheath. As such, movement of each section of the split distal portion of the sheath inwards from the radially outward position (first configuration) and/or the central position, suitably causes the anchoring portions to move the tissue inwards, i.e., from the outer edge of the opening in the tissue, by engagement therewith, such that the opening in the tissue is caused to become substantially closed.
[67] The device of the present invention is suitably operable to temporarily close the opening in the tissue (by the action of one or more of the elements of the device as disclosed herein). Suitably, the device may be operable to temporarily close the opening in the tissue in preparation for permanent closure.
[68] Suitably, upon closure of the opening in the tissue using the device, the tissue may be sealed. In other words, the tissue, once closed, may be sealed such that it remains closed upon removal of the device. As such, a means to seal the tissue (i.e., upon closure of the opening in the tissue) may be used in conjunction with the device of the invention. For example, a fastening means may be used in conjunction with the device of the invention. Examples of suitable fastening means include, but are not limited to: adhesives, such as bio-adhesives; sutures; clips; pins; staples; and combinations thereof.
[69] As such, according to a further aspect of the present invention there is provided a kit, the kit comprising a device in accordance with the first aspect of the invention and a fastening means. Suitably, the fastening means is operable to seal the opening in the tissue.
[70] Suitably, a clip may be used in conjunction with the device of the invention to seal the tissue. The clip may be provided separately and/or may be removably attached to the device. Suitably, the device may comprise a removable clip. The removable clip may be disposed on any suitable portion of the device. Suitably, the removable clip may be slidably disposed on the sheath.
[71] Suitably, the clip may be operable to move from a first open position, when slidably disposed on the sheath, to a second closed position, when removed from the sheath. The clip may be biased to the second closed position. It will be appreciated by a person skilled in the art that the clip, when slidably disposed on the sheath, may have stored energy because it is in a position against the position to which it is biased. Therefore, upon removal of the clip from the sheath, the clip may automatically adopt the closed position to which it is biased. In the closed position, the clip suitably engages and seals the tissue. Details of suitable clips, and the mechanism by which they work, are further defined in WO 2010/099437 A1 , the full contents of which are fully incorporated herein by reference.
[72] The clip may be formed from any suitable material. Suitably, the clip may be formed from a material that has sufficient strength to ensure that the tissue remains sealed after closure of the opening therein and has sufficient flexibility such that it can move between the first and second configurations (wherein the first and second configurations are as defined herein). For example, the clip may be formed from an elastic material. Suitably, the clip may be formed from an elastic material which has both elasticity and shape memory. By being formed from a material which has elasticity and shape memory, the clip may be operable to adopt the second, closed configuration upon removal from the device, such as from the sheath.
[73] Suitably, the clip may comprise nitinol. Suitably, the clip may be bioabsorbable, for example the clip may comprise a magnesium alloy.
[74] The clip may be caused to be removed from the device, such as from the sheath, by any suitable means. Suitably, as already defined herein, the device may further comprise an outer carriage slidably disposed over the sheath. Suitably, the outer carriage may be operable to slidably remove the clip from the device, such as from the sheath. For example, in use, the outer carriage may be pushed downwards from the proximal end of the sheath toward the distal end of the sheath, manually by a user, by mechanical means, by electronic means, or otherwise, causing the outer carriage to push down against the clip and, in doing so, cause the clip to be slidably removed from the sheath.
[75] Suitably, as already defined herein, the device may comprise a hypodermic tube. Suitably, the hypodermic tube may be operable to detect when the shaft has been withdrawn from the opening in the vessel wall allowing the clip can be deployed to suitably engage and seal the tissue.
[76] According to a second aspect of the present invention there is provided a device according to the first aspect of the invention for use in sealing an opening in a tissue.
[77] According to a third aspect of the present invention there is provided a method of closing an opening in a tissue, the method comprising the steps of; a) inserting a device according to any one of claims 1 to 20 into the opening in the tissue; b) causing the expandable support portion to extend radially outward to provide a surface which prevents or reduces inversion of the tissue; c) partially withdrawing the shaft such that the surface provided by the expandable support portion engages with the tissue surrounding the opening in the tissue and causes the tissue to become everted; d) causing the anchoring portions to engage the tissue by at least partially penetrating the tissue; e) causing each section of the split distal portion of the sheath to move inwards from the radially outward position, such that the anchoring portions are caused to move the everted tissue inwards from the outer edge of the opening in the tissue such that the opening in the tissue becomes substantially closed; and f) sealing the tissue with a fastening means.
[78] Suitable features of the second and thirds aspects of the invention are as defined herein in relation to the first aspect of the present invention.
[79] Suitably, the method comprises the step of inserting a device having a clip slidably disposed thereon, such as slidably disposed on the sheath. As such, the method may further comprise the step of removing the clip from the device, such as from the sheath, such that it is caused to move from the first open configuration to the second closed position thereby engaging and sealing the tissue.
[80] According to a fourth aspect of the present invention there is provided use of a device according to the first aspect to seal an opening in a tissue, for example to seal an opening in a tissue according to the method of the third aspect.
[81] Suitable features of the fourth aspect of the invention are as defined herein in relation to the first, second and/or third aspects of the present invention.
[82] According to a fifth aspect of the invention there is provided a device according to the first aspect for use in the method of the third aspect.
[83] Suitable features of the fifth aspect of the invention are as defined herein in relation to the first, second, third and/or fourth aspects of the present invention.
[84] All of the features contained herein may be combined with any of the above aspects and in any combination. BRIEF DESCRIPTION OF DRAWINGS
[85] For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which:
[86] Figure 1 shows a schematic view of a device according to an exemplary embodiment of the invention.
[87] Figure 2 shows a schematic view of a device according to an exemplary embodiment of the invention partially extending through a blood vessel wall.
[88] Figure 3 shows a schematic view of a device according to a further exemplary embodiment of the invention, wherein the shaft has been partially withdrawn from a blood vessel wall.
[89] Figure 4 shows a schematic view of a device according to a further exemplary embodiment of the invention, wherein the shaft has been fully withdrawn from a blood vessel.
[90] Figure 5 shows a schematic view of a device according to a further exemplary embodiment of the invention, wherein the device comprises a removable clip slidably disposed thereon.
DESCRIPTION OF EMBODIMENTS
[91] Figure 1 shows an example device (100) that may be used for sealing an opening in tissue, for example a wall of a blood vessel (or other tubular structure). The device 100 includes a shaft (102) having a concave distal end (104) and an expandable support portion (106). The expandable support portion (106) is proximate the distal end (104) of the shaft (102). The shaft (102) has an outer wall defining a lumen (not shown) extending through the shaft (102) from the proximal end (not shown) to the distal end (104). The shaft (102) is formed from stainless steel and has a diameter of 11 mm. The lumen (not shown) has a diameter of from 9-10 mm.
[92] As described, the shaft (102) has an expandable support portion 106 proximate the distal end (104) of the shaft (102). The expandable support portion (106) is attached to the shaft (102) and is an expandable flange in the form of a segmented a segmented portion (108) having multiple segments. Each segment of the segmented portion (108) comprises two sections (110, 112), wherein each section (110, 112) of a segment is operable to fold substantially flat against one another when the segmented portion (108) is extended radially outwards. As shown in Figure 1 , the two sections (110, 112) of each segment of the segmented portion (108) are able to move, and ultimately fold flat against one another, by virtue of the fact that they have a bendable region (114). The segmented portion is formed from nitinol.
[93] As shown in Figure 1 , each segment of the segmented portion (108) lies substantially parallel to the longitudinal axis of the shaft 102 (i.e., each segment of the segmented portion (108) lies substantially flat against the outer surface of the shaft (102)). This arrangement defines a first configuration (as defined herein). Each segment of the segmented portion (108) is operable to extend radially outward from the outer surface of the shaft (102) in a second configuration (as defined herein).
[94] The device (100) also includes a sheath (116) slidably disposed over the shaft (102). As such, the sheath (116) comprises an outer wall which defines a lumen (not shown) extending through the sheath (116) from the proximal end (not shown) to the distal end (118) along the longitudinal axis of the sheath (116). The sheath (1 16) is formed from stainless steel.
[95] The sheath (116) comprises a split distal portion (118) having two sections, wherein each section of the split distal portion (118) is in a substantially central position. As shown in Figure 1 , as each section of the split distal portion (118) of the sheath (116) is positioned radially outward such that the diameter of the split distal portion (118) of the sheath (116) is greater than the diameter of the proximal end (not shown) of the sheath (116). This defines a first configuration (as defined herein). Each section of the split distal portion (118) of the sheath (1 16) by the shaft (102), i.e., because the sheath (116) is slidably disposed over the shaft (102). The diameter of the shaft (102) is such that it forces each section of the split distal portion (118) of the sheath (116) radially outward, i.e., against the radially inward position to which each section of the split distal portion (118) of the sheath (116) is biased.
[96] The device (100) includes a plurality of anchoring portions (120). Each anchoring portion (120) is located at the distal end of a section of the split distal portion (118) of the sheath (1 16). The device includes four anchoring portions (120; only two shown), wherein two anchoring portions (120) are located on each section of the split distal portion (118) of the sheath (116). Each anchoring portion (120) is in the form of a needle and each needle is formed from stainless steel. Each needle is approximately 9 mm apart, i.e., each needle is approximately 9 mm from the needle on the opposing side. In other words, the diameter of an imaginary circle drawn around the needles is approximately 9 mm.
[97] The device (100) also includes an outer carriage (122) slidably disposed over the sheath (116). As such, the outer carriage (122) comprises an outer wall which defines a lumen (not shown) extending therethrough along the longitudinal axis.
[98] Figure 2 shows an example device (100) partially extending through an opening (20) in a wall of a blood vessel (22). The device (100) is the same device (100) as shown in Figure 1 . The device (100) extends into the lumen (24) of the blood vessel. As shown in Figure 2, during insertion of the device (100) into the opening (20) in the wall of the blood vessel (22), the expandable support portion (106) of the shaft (102) is substantially parallel to the longitudinal axis of the shaft (102), i.e., adopts the first configuration (as defined herein). In other words, each segment of the segmented portion (108) lies substantially parallel to the longitudinal axis of the shaft (102), i.e., lies substantially flat against the outer surface of the shaft (102), and in doing so adopts the first configuration (as defined herein). By adopting the first configuration (as defined herein), the shaft (102), including the expandable support portion (106), is able to enter the lumen (24) of the blood vessel (22) without causing (further) damage to the tissue.
[99] As described herein, the device (100), partial withdrawal of the shaft (102) from the opening (20) in the wall of the blood vessel (22) may cause eversion of the tissue. Figure 3 shows an example device (100), wherein the shaft (102) which has been partially withdrawn from the opening (20) in the wall of the blood vessel (22). The device (100) is the same device (100) as shown in Figure 1. As shown in Figure 3, the expandable support portion (106) of the shaft (102) has been extended radially outward. The expandable support portion (106) may have been caused to extend radially outward by any of the means defined herein, or by any other suitable means. Suitably, is this exemplary embodiment, the expandable support portion (106) has been caused to extend radially outward by the user actuating a spring loaded button (not shown) at the proximal end (not shown) of the device (100). Actuating the button (not shown), by the user pushing down on the button, caused the expandable support portion (106) of the shaft (102) to extend radially outward. As shown in Figure 3, when in this configuration (i.e., extended radially outward and/or in the second configuration as defined herein) each section (110, 112) of each segment of the segmented portion (108) is folded flat against each another, by virtue of the fact that they have bent at the bendable region (114). In the configuration as shown in Figure 3, the expandable support portion (106) provides a substantially flat surface (30) which lies perpendicular to the longitudinal axis of the shaft (102). The diameter of the expandable support portion (106) in this configuration is larger than the opening (20) in the wall of the blood vessel (22) and also extends beyond the diameter defined by the anchoring portions (120). Advantageously, when the diameter of the expandable support portion (106), in the radially extended position, is larger than the diameter defined by the anchoring portions (120) the expandable support portion (106) reduces, or prevents, damage to the back wall of the blood vessel.
[100] As shown in Figure 3, upon partial withdrawal of the shaft (102) from the opening (20) in the wall of the blood vessel (22), the surface (30) provided by the expandable support portion (106) when extended radially outward engages with the tissue surrounding the opening (20) of the blood vessel (22) causing eversion of the tissue. The surface (30) provided by the expandable support portion (106) when extended radially outward reduces or prevents the tissue surrounding the opening (20) in the blood vessel (22) from folding and/or reduces or prevents the tissue surrounding the opening (20) in the blood vessel (22) from becoming deformed and/or prolapsing into the lumen (24) of the blood vessel (22).
[101] In this embodiment, the anchoring portions (120) of the device (100) are engaged with the tissue surrounding the opening (20) in the wall of the blood vessel (22). Each anchoring portion (120; only two shown) have fully penetrated the tissue surrounding the opening (20) in the wall of the blood vessel (22). The anchoring portions (120) are substantially perpendicular to the wall of the blood vessel (22) when engaging with the tissue. As shown in Figure 3, when the shaft is only partially withdrawn the split distal portion (118) of the sheath (116) remains in the radially outward position, i.e., first configuration.
[102] Upon engagement of the tissue by the anchoring portions (120), the expandable support portion (106) of the shaft (102) may be caused to move from the extended radially outward position, i.e., the second configuration (as defined herein), to lie substantially flat against the outer surface of the shaft (102), i.e., to the first configuration (as defined herein). Advantageously, the dual action of the surface (30) provided by the expandable support portion (106) and the engagement of the tissue surrounding the opening (20) in the wall of the blood vessel (22) means that the tissue is sufficiently everted, and supported, to allow removal of the surface (30) provided by the expandable support portion (106) without causing substantial amounts of tissue to become everted. The expandable support portion (106) may have been caused to lie substantially flat against the outer surface of the shaft (102) by any of the means defined herein, or by any other suitable means. Suitably, is this exemplary embodiment, the expandable support portion (106) has been caused to extend radially outward by the user actuating a spring loaded button (not shown) at the proximal end (not shown) of the device (100). Actuating the button (not shown), by the user pushing down on the button, caused the expandable support portion (106) of the shaft
[102] to extend radially outward.
[103] As shown in Figure 4, removal of the shaft (not shown) causes each section the split distal portion (118) of the sheath (116) to move radially inward. The device (100) is the same device (100) as shown in Figure 1 . It will be appreciated by a person skilled in the art that removal of the shaft (not shown) is sufficient to cause each section of the split distal portion (1 18) of the sheath (116) to move inward because each section of the split distal portion (118) is biased radially inward. In certain embodiments, each section of the split distal portion (118) of the sheath (1 16) may be forced further inwards by the action of the outer carriage (122). For example, sliding the outer carriage (122), such as manually or by any other suitable means, down the sheath (116) from the proximal end (not shown) to the distal end (118) may cause each section of the split distal portion (118) of the sheath (116) to move further inwards, suitably due to the diameter of the lumen (not shown) of the outer carriage (not shown).
[104] As can be seen in Figure 4, movement of the split distal portion (118) of the sheath (116), and thus the anchoring portions (120), inwards causes the anchoring portions (120) to move the tissue inwards from the outer edge of the opening (20) in the wall of the blood vessel (22), such that the opening (20) in the wall of the blood vessel (22) becomes substantially closed. It will be appreciated by a person skilled in the art that the anchoring portions (120) are able to move the tissue in this manner by virtue of their engagement therewith. In this configuration, as shown in Figure 4, the opening (20) in the wall of the blood vessel (22) is temporarily closed. [105] The opening (20) in the wall of the blood vessel (22) may be permanently closed by any of the means described herein. For example, the opening (20) in the wall of the blood vessel (22) may be permanently closed by a clip.
[106] Figure 5 shows a device (100) having a removable clip (50) slidably disposed on the sheath (116). The device (100) is the same device (100) as shown in Figure 1 . The removable clip (50) is formed from nitinol. The removable clip, as slidably disposed on the sheath (1 16), is in a first open position and has stored energy because it is in a position against which it is biased. The removable clip (50) is biased to a second closed position which it may adopt upon removal from the sheath (116).
[107] The removable clip (50) may be removed from the sheath (116) by sliding the outer carriage (122) down the sheath (116) from the proximal end (not shown) to the distal end (118). Moving, i.e., by sliding, the outer carriage (122) in this manner has the dual advantage of enabling the removable clip (50) to be removed from the sheath (116) and causing each section of the split distal portion (118) of the sheath (118) to be forced even further radially inwards, thus ensuring a tight seal of the opening (20) in the wall of the blood vessel (22). Upon removal of the removable clip (50) from the sheath (1 16), i.e., by the action of the outer carriage (122), the clip adopts the second, closed position, thus permanently closing the opening (20) in the wall of the blood vessel (22). After the opening (20) in the wall of the blood vessel (22) has been permanently closed, the device (100) may be fully removed.
[108] "And/or" where used herein is to be taken as specific disclosure of each of the two specified features or components with or without the other. For example, "A and/or B" is to be taken as specific disclosure of each of (i) A, (ii) B and (iii) A and B, just as if each is set out individually herein. Unless context dictates otherwise, the descriptions and definitions of the features set out above are not limited to any particular aspect or embodiment of the invention and apply equally to all aspects and embodiments which are described.
[109] All documents mentioned in this specification are incorporated herein by reference in their entirety.
[1 10] Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.
[1 11] All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. [112] Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.
[113] The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.