The disclosure relates to devices, systems and methods for occlusion.
The need for filling, embolizing, or occluding (which terms may be used herein interchangeably) arises in various settings. As it relates to the cardiovascular system, distension of the vessel wall creates aneurysms that can range in size from small (e.g., intracranial “berries”) to large (e.g., distension of the aortic wall). Aneurysms relatively frequently involve side branch vessels and can be convoluted. Irrespective of the size and location, aneurysms can be problematic and often require occlusion.
Other clinical applications involving therapeutic occlusion or embolization include treatment of arterio-venous malformations, hemorrhagic stroke, vascular trauma and/or perforation, and closure of mural defects in the cardiovascular system.
Another application wherein occlusion is useful is in the treatment of cancer. For example, interventional oncology often necessitates the occlusion of vasculature to “starve” diseased tissue (e.g., a tumor) and additionally, to isolate therapeutic agents in contact with diseased tissue.
The need for occlusion may also arise in the context of endovascular devices, for example stents, stent grafts, heart valves, implants, catheters, etc. Often an incomplete seal exists between an endovascular device and surrounding tissue, for example, in the case of an incomplete endovascular deployment or as a result of the irregular tissue deformation created by an aneurysm. An incomplete seal may also be found between a plurality of endovascular devices. Such “endoleaks” often require occlusion.
Various approaches to occlusion exist in the prior art. For example, embolic coils of metallic wire (e.g., platinum) and PET (e.g., Dacron) are deployed from stent-crossing catheters to occlude aneurysms. Mechanical vessel occluders and liquid embolic agents are also known and used, for example, to sequester diseased tissue.
Yet, the existing approaches may suffer from drawbacks. For example, metallic coils may not be suitable for smaller applications and are not radiographically transparent, maximum sequestration of diseased tissue is often difficult to achieve, and no proven technique exists for occlusion of certain types of endoleaks.
What is therefore needed in the art is a radiographically transparent or temporarily radio-opaque occluder suitable for use in connection with aneurysms of all sizes, sequestration of diseased tissue, and endoleaks, to name just a few applications. What is also needed in the art is an occluder having porous properties. The present disclosure addresses these needs and others.
This specification describes devices, systems, and processes for endovascular occlusion, such as occlusion of blood vessel aneurysms. In brief, various embodiments are disclosed whereby a catheter delivers a first material to occlude an endovascular space. Optionally, the catheter may also be used to deliver a second material to combine with and expand the first material, while the first material is disposed in the endovascular space to be occluded.
In a first general aspect, an occlusion device includes an elongate element having a first configuration and a second configuration, where the first configuration has a relatively low crossing profile and the second configuration is tumbled. The elongate element includes at least one modification to increase the surface area, surface drag, and/or axial profile of the elongate element, and the elongate element has a first volume in the first configuration and a second volume greater than the first volume in the second configuration after an administration of an alginate.
In a second general aspect, a system for occluding includes an elongate element located within a lumen of a catheter, wherein the elongate element is configured to be delivered to a site for occlusion upon hydraulic flow through the lumen of the catheter. The elongate element is porous and imbibed with at least one of a therapeutic composition, swellable agent, bioactive agent, drug, or compound. The elongate element comprises a first configuration suitable for delivery, and a second configuration suitable for occlusion.
In a third general aspect, a method of occluding includes imbibing a porous elongate element comprised of ePTFE with a calcium-containing solution, delivering, via a delivery catheter, the calcium-imbibed porous elongate element to a target occlusion site, and administering, after the calcium-imbibed porous elongate element has been completely delivered to the target occlusion site and resides entirely within a volume defined by the target occlusion site, an alginate-containing solution to the target occlusion site.
In a fourth general aspect, a method of occluding includes accessing a target occlusion site with a catheter that includes a plurality of lumens, each of the lumens housing a separate elongate element. The method also includes delivering to the target occlusion site via a first lumen of the plurality of lumens, a first elongate element. The method further includes delivering to the target occlusion site via a second lumen of the plurality of lumens, a second elongate element.
In a fifth general aspect, a system for occluding includes a catheter that comprises a proximal end, a distal end, and a delivery lumen that extends from the proximal end to a location at or near the distal end. The system also includes a dispenser that comprises a plurality of dispensing lumens, each of the dispensing lumens housing a separate elongate element, wherein the dispenser is positionable with respect to the proximal end of the catheter such that, for each dispensing lumen of the plurality of dispensing lumens, the dispenser may be positioned so that the respective dispensing lumen is in fluid communication with the delivery lumen of the catheter.
In a sixth general aspect, a method of occluding includes delivering a first elongate element to a target occlusion site, the first elongate element delivered via a delivery lumen of a delivery catheter from a first dispensing lumen of a dispenser comprising a plurality of dispensing lumens. The method also includes positioning the dispenser to align a second dispensing lumen of the plurality of dispensing lumens with a proximal end of the delivery lumen. The method further includes delivering a second elongate element to the target occlusion site via the delivery lumen of the delivery catheter from the second dispensing lumen.
According to various aspects of the invention, an elongate element comprises at least a first configuration suitable for delivery and a second configuration suitable for occlusion. In example embodiments, the elongate element is biased toward the second configuration, while in other embodiments, the elongate element has no bias such that the second configuration is random.
In example embodiments, the elongate element is porous to imbibe one or more of a reagent, therapeutic composition, agent, drug, or compound.
Example embodiments of the present invention comprise an elongate element modified to promote a desired therapeutic response like thrombogenesis, assist in increased hemostatic properties, allowing volumetric changes to the elongate element, and/or enhance its delivery or deployment by, for example, adjusting a dimensional characteristic. The elongate element may be imbibed with a first reagent that serves to activate or react with a second reagent. The second reagent may be used to hydraulically deliver the elongate element. The elongate element of the present invention may be delivered over a catheter or out from within a catheter. The elongate element of the present invention may also be surgically implanted and activated in situ. Further, the elongate element may be incorporated into an implantable prosthesis.
Other aspects, features, and advantages will be apparent from the description, the drawings, and the claims.
Like reference symbols in the various drawings indicate like elements.
Persons skilled in the art will readily appreciate that various aspects of the present disclosure may be realized by any number of methods and apparatuses configured to perform the intended functions. Stated differently, other methods and apparatuses may be incorporated herein to perform the intended functions. It should also be noted that the accompanying drawing figures referred to herein are not all drawn to scale, but may be exaggerated to illustrate various aspects of the depicted embodiments, and in that regard, the drawing figures should not be construed as limiting. Finally, although the embodiments may be described in connection with various principles and beliefs, the embodiments should not be bound by theory.
With reference now to
Those skilled in the art will appreciate that example elongate elements may vary dimensionally depending on the particular application. However, an example embodiment of an elongate element having a solid cross section may have a diameter of from about 0.005 in to about 0.500 in, preferably about 0.020 in (about 0.5 mm). Similarly, an example embodiment of an elongate element having a tubular structure may have an outer diameter of from about 0.005 in to about 0.500 in, preferably about 0.020 in (about 0.5 mm), and an inner diameter of from about 0.001 in to about 0.100 in, preferably about 0.015 in. In terms of length, example elongate elements may be from about 1.0 in to about 20.0 in, preferably about 6.0 in. In terms of volume occupying capacity, example elongate elements in their second configuration may occupy from less than or about 0.5 mL (e.g., in the case of cerebral aneurysms) to more than or about 250 mL (e.g., in the case of aortic aneurysms). Again, however, elongate elements may be smaller or larger depending on the particular application.
Moreover, while the foregoing embodiments have been described in terms of diameter, those skilled in the art will appreciate that example elongate elements may vary cross-sectionally depending on the particular application. More specifically, elongate elements can have any cross-sectional shape including but not limited to profiles that are circular, oval, triangular, square, polygon shaped or randomly shaped. Additionally, it is understood that cross-sectional shape may vary as a function of activation or deployment.
In some embodiments, a cross-sectional dimension of the elongate element can be varied along its length. For example, an elongate element with a circular cross-section can have a different diameter at different positions along the length of the elongate element (e.g., resulting in a tapered profile). Varying the cross-sectional dimension in a portion of the elongate element can generally affect the flexibility and column strength of the elongate element in that portion. For instance, a portion of a circular cross-sectional elongate element with a reduced diameter can generally be more flexible and have a lower column strength than a portion that has a larger diameter (assuming all other factors are constant).
Example embodiments comprise an elongate element that exhibits flexibility. Example embodiments comprise an elongate element having a low column strength, for example, so as to “tumble” on itself (as that term is defined herein), and thereby not pierce a vessel wall, when coming into contact with a vessel wall. In some embodiments, elongate element 10 can exhibit greater flexibility and lower column strength at its trailing-end portion than at its leading-end portion. The purpose of more flexibility at the trailing-end can be to enable the last portion entering a space to more easily “tumble” on itself, thereby helping the elongate element to more thoroughly fill the space as the open space become smaller. Greater flexibility at the trailing-end portion can be achieved, for example, by reducing the cross-sectional size of the trailing-end portion, or by varying the modulus of elasticity of the elongate element along its length while maintaining a consistent cross-sectional size (or by a combination of such factors). Still other example embodiments comprise a distensible elongate element, or in other words, an elongate element that is capable of radial stretching or expansion. The elongate element is porous in various example embodiments, and may be non-metallic and/or radiographically transparent.
Some embodiments of elongate element 10 can include particular weakened regions to facilitate the shearing, tearing, fracturing, severing, or otherwise separating of elongate element 10. This feature can be useful, for example, when the space being occluded has received the proper amount of elongate element 10, and elongate element 10 can then be severed to stop further delivery.
Suitable materials for use in connection with an example elongate element may comprise polymers, such as a fluoropolymer like expanded polytetrafluoroethylene (“ePTFE”). For example, U.S. Pat. No. 5,814,405 to Branca et al., which is incorporated herein by reference in its entirety for all purposes, describes a suitable ePTFE material. However, those skilled in the art will appreciate that any materials may be used that exhibit the desired properties described herein, for example, nylons, polycarbonates, polyethylenes, polypropylenes, as well as combinations or sub-combinations thereof.
In embodiments comprising ePTFE, the fibril and node openness (i.e., the ePTFE's permeability or porosity) may be selected for optimum wettability. In example embodiments, the elongate element comprises a plurality of concentric layers differing in their wettability. In example embodiments, the elongate element's permeability is selected to enable flushing of air, prior to insertion. In this regard, the elongate element may be permeable to saline but not to a reagent or therapeutic agent (e.g., one or more reagent or therapeutic agent imbibed or enclosed within the elongate element) so as to not unintentionally flush said reagent or therapeutic agent. The elongate element in example embodiments comprises at least a first configuration suitable for delivery and a second configuration suitable for occlusion. For example, with reference again to
In contrast, and with reference to
In some embodiments, the elongate element may be removable following implantation. In this regard, the elongate element may comprise a third configuration suitable for removal. Not unlike the first configuration, the third configuration may be selected to minimize the crossing profile of the elongate element, for example to facilitate removal of the elongate element together with an endovascular device through tortuous passageways.
In some embodiments, the elongate element may be configured to return to a first configuration suitable for removal from a second configuration suitable for occlusion. In this regard, the first and third configurations may be substantially the same.
In example embodiments, the elongate element is porous to imbibe a reagent or any other material. As used herein, “imbibe” means to absorb, take in, or otherwise assimilate. The reagents or materials can include therapeutic compositions, bioactive agents, drugs, or compounds, including but not limited to: small molecule drugs; large molecule drugs; medicaments; cardiovascular agents; sclerotic agents; chemotherapeutics; antimicrobials; antibiotics (e.g., dactinomycin (actinomycin O) daunorubicin, doxorubicin, and idarubicin), anthracyclines, mitoxantrone, bleomycins, plicamycin (mithramycin) and mitomycin); anesthetics; alkaloids (nicotine); hemostatics; antihistamines; antitumor agents; antilipids; antifungals; antimycotics; antipyretics; antirestenotics (e.g., pimecrolimus, cytochalasin, dicumarol, cyclosporine, latrunculin A, methotrexate, tacrolimus, halofuginone, mycophenolic acid, genistein, batimistat, dexamethasone, cudraflavone, simvastatin, prednisolone, doxorubicin, bromopyruvic acid, cilostazol, carvedilol, mitoxantrone, tranilast, etoposide, hirudin, trapidil, mitomycin C, abciximab, cilostazol, irinotecan, estradiol, diaziquone, dipyridamole, melatonin, colchicine, nifedipine, vitamin E, paclitaxol, diltiazem, vinblastine, verapamil, vincristine, rapamycin (e.g., Albumin-Bound (Nab)-Rapamycin (Abraxane), angiopeptin, everolimus, heat shock proteins, zotarolimus, nitroglycerin, prednisone); antimitotics/antiproliferatives (e.g., including natural products such as vinca alkaloids (e.g., vinblastine, vincristine, and vinorelbine), paclitaxel, epidipodophyllotoxins (e.g., etoposide, teniposide), alkylating agents such as nitrogen mustards (mechlorethamine, cyclophosphamide and analogs, melphalan, chlorambucil), ethylenimines and methylmelamines (hexamethylmelamine and thiotepa), alkyl sulfonates-busulfan, nirtosoureas (carmustine (BCNU) and analogs, streptozocin), trazenes—dacarbazinine (DTIC)); antiproliferative/antimitotic antimetabolites such as folic acid analogs (methotrexate), pyrimidine analogs (fluorouracil, floxuridine, and cytarabine), purine analogs and related inhibitors (mercaptopurine, thioguanine, pentostatin and 2-chlorodeoxyadenosine {cladribine}); platinum coordination complexes (cisplatin, carboplatin), procarbazine, hydroxyurea, mitotane, aminoglutethimide; hormones (e.g., estrogen); vasodilators; hypertensive agents; oxygen free radical scavengers; vitamins; antivirals; analgesics; antiinflammatories (e.g., adrenocortical steroids (cortisol, cortisone, fludrocortisone, prednisone, prednisolone, 6a-methylprednisolone, triamcinolone, betamethasone, and dexamethasone, dexamethasone sodium phosphate, dexamethasone acetate, beclomethasone dipropionate); non-steroidal agents (e.g., salicylic acid derivatives such as aspirin); para-aminophenol derivatives e.g., acetominophen; indole and indene acetic acids (indomethacin, sulindac, and etodalac), heteroaryl acetic acids (tolmetin, diclofenac, and ketorolac), arylpropionic acids (ibuprofen and derivatives), anthranilic acids (mefenamic acid, and meclofenamic acid), enolic acids (piroxicam, tenoxicam, phenylbutazone, and oxyphenthatrazone), nabumetone; gold compounds (auranofin, aurothioglucose, gold sodium thiomalate); diagnostic agents; visualization agents; angiographic contrast agents; peptides; proteins; antibodies (e.g., britumomab (Zevalin), bevacizumab (Avastin), rituximab (Rituxan), Cetuximab (Erbitux), Ofatumumab (Arzerra), Panitumumab (Vectibix), Trastuzumab (Herceptin), and Tositumomab (Bexxar)); enzymes (e.g., L-asparaginase); antiplatelet agents (such as G(GP)IIbIIIa inhibitors and vitronectin receptor antagonists); insulin; phase contrast agents, and radio-opaque agents; thrombolytics intended to facilitate the breakup of thrombus; anticoagulants (e.g., heparin, synthetic heparin salts and other inhibitors of thrombin), intended to prevent thrombosis; fibrinolytic agents (such as tissue plasminogen activator, streptokinase and urokinase), aspirin, dipyridamole, ticlopidine, clopidogrel, abciximab; antimigratories; antisecretories (e.g., breveldin); immunosuppressives: (cyclosporine, tacrolimus (FK-S06), sirolimus (rapamycin), azathioprine, mycophenolate mofetil); angiogenic agents: vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF); angiotensin receptor blocker; nitric oxide donors; anti-sense oligionucleotides and combinations thereof; cell cycle inhibitors, mTOR inhibitors, and growth factor signal transduction kinase inhibitors; RNA; viruses; and combinations thereof.
Example embodiments comprise an elongate element modified to promote a desired therapeutic response like thrombogenesis, assist in increased hemostatic properties and/or enhance its delivery or deployment by, for example, adjusting a dimensional characteristic. As used herein, “adjusting” means increasing, decreasing, maximizing, minimizing, or otherwise optimizing. As used herein, “dimensional characteristic” may comprise surface area, surface drag, volume and/or axial profile. Example modifications may be made to the elongate element in its first and/or its second configuration.
By way of non-limiting example, in a preferred embodiment, the volume of an elongate element in its first configuration is less than needed to completely occlude a target occlusion space, but its volume in its second configuration substantially completely occludes or otherwise occupies the space. For example, the tumbled elongate element may only fill 80% of the space to be occluded, but through gelation or cross-linking it may fill approaching 100% of the space to be occluded.
In this regard, a preferred embodiment comprises imbibing the elongate element with a first reagent that serves to activate or react (e.g., to form a gel or to cross-link) with a second reagent. In a preferred embodiment, the first and second reagents are a calcium chloride solution and a sodium alginate solution, respectively. For example, the elongate element 10 can be imbibed with a solution of approximately 10% calcium chloride. After delivery of the imbibed elongate element to the endovascular occlusion site, a solution of approximately 1.6-1.8 wt % sodium alginate can be delivered to the occlusion site to thereby form a gel with the elongate element in situ. In another example embodiment, the elongate element 10 can be imbibed with sodium alginate, and the calcium chloride solution can be subsequently provided to form a gel with the elongate element in situ. In another example embodiment, the elongate element 10 can be imbibed with a block copolymer that can be cross-linked with polyvalent compounds, and the second reagent can be a polyvalent compound.
Alginic acid (alginate) is an example block copolymer consisting of glucuronic acid and mannuronic acid that can be cross-linked with polyvalent compounds. Polyvalent compounds that may be used include divalent or trivalent metal salts such as barium, lead, copper, strontium, cadmium, calcium, zinc, nickel, cobalt, manganese, iron and magnesium. Polyvalent compounds may also include cationic polymers such as polyethyleneimine, poly-L-lysine, diethylaminoethyl dextran, polyvinylamine, chitosan, and poly(allylamine). A combination of polyvalent cations and/or cationic polymers may also be used to cross-link the block copolymer.
The second reagent may also be used to hydraulically deliver the elongate element, as described herein. The product of the first and second reagents may promote a desired therapeutic response like thrombogenesis, assist in increased hemostatic properties and/or enhance delivery of the elongate element by, for example, increasing the volume or otherwise adjusting a dimensional characteristic of the elongate element in its second configuration through gelation or cross-linking, to name a few examples. In some embodiments a non-reactive liquid (e.g., saline) can be used to hydraulically deliver the elongate element.
Various compounds can be incorporated into a gel according to example embodiments, including the materials described herein and compounds that may be especially relevant for hemostatic applications, for example, collagen, oxidized regenerated cellulose, gelatin, thrombin, fibrin and/or fibrin sealants, and/or synthetic sealants (e.g. crosslinked PEG, cyanoacrylate, etc.). Combinations of these compounds may also be used.
Fibrous composites may be formed by combining a gel according to example embodiments and/or crosslinked polymer compositions with fibrous materials. Said fibrous materials may be ceramic, inorganic, metallic or polymeric. Example ceramic and inorganic materials include, but are not limited to, alumina, alumina silicate, bismuth titanate, boron nitride, calcium phosphate, carbon, carbon nanotubes, glass, graphite, hydroxyapatite, lead metaniobate, lead nickel niobate, lead zirconate titanate, lithium aluminate, oxide nanotubes, silicon carbide, silicone nitride, tin oxide, titanium dioxide, yttrium aluminum garnet, zirconium diboride, and combinations thereof. Example metallic fibrous materials include, but are not limited to, aluminum, copper, gold, iron, magnesium, nickel-titanium, platinum, silver, steel, alloys thereof, and combinations thereof. Example polymeric fibrous materials include, but are not limited to, cellulose, cellulosic derivatives (e.g., carboxymethylcellulose and hydroxyethylcellulose), chitin, chitosan, collagen, fluoropolymers, polyacrylates, polyamides, polyanhydrides, polyesteramides, polyesters, polyesterurethanes, polyetheramides, polyetheresters, polyetheresterurethanes, polymethacrylates, polyolefins, polyurethanes, polyvinylalcohol, and combinations thereof.
In embodiments comprising a tubular elongate element, its lumen in a first configuration may be substantially patent (i.e., open) and its lumen in a second configuration may be substantially non-patent (i.e., obstructed). By way of non-limiting example, the lumen of a tubular elongate element may be obstructed with a gel, as described herein, in its second configuration.
Other modifications may be made to the elongate element, alone or in combination, to adjust a dimensional characteristic and thereby promote a desired therapeutic response like thrombogenesis, assist in increased hemostatic properties and/or enhance its delivery or deployment.
In this regard, mechanical roughening and/or plasma treating may contribute to an increased surface area or otherwise adjusted dimensional characteristic. Similarly, adherence of fibers 31 (e.g., ePTFE, Dacron, etc.) to the surface of an elongate element 30 may be used, for example, as shown in
Bioabsorbable polymer coatings (e.g., bioabsorbable non-woven self-cohered web materials, such as disclosed in U.S. Pat. No. 7,659,219, which is hereby incorporated by reference for all purposes), swelling hydrogel coatings, as well as heat treatments (e.g., methods to coalesce ePTFE fibrils and leave nodes standing) may also be used to provide to an adjusted dimensional characteristic. The wettability of the elongate element may also be altered in example embodiments (e.g., with PVA to make an ePTFE elongate element more hydrophilic). See U.S. Pat. No. 5,874,165, which is hereby incorporated herein by reference in its entirety for all purposes, for examples of imbibing ePTFE with a hydrogel.
With reference now to
With reference now to
Turning now to
More broadly, any portion of the elongate element (or any structural modification made thereto) may comprise a radio-opaque or echogenic element that enhances imaging or detection of the elongate element during and following implantation, such as disclosed in U.S. Publication No. 2004/0024448, which is hereby incorporated by reference for all purposes. Preferred radio-opaque markers may be comprised of one or more of tungsten, gold, platinum and the like. In applications of the present invention wherein the elongate element may be removable following implantation, radio-opaque elements may be particularly advantageous.
Other example embodiments may be rendered hydrophilic and then soaked in radio-opaque contrast prior to delivery. Soaking in contrast will facilitate a temporarily radiographically visible device. Once the contrast washes out, the device will become radiographically transparent. Additionally, in embodiments comprising ePTFE, un-wet ePTFE may be sufficiently echogenic during delivery and eventually wet out and become transparent after delivery. Similarly, as previously described, the second reagent can be combined with a radio-opaque contrast agent.
In general, any modification to adjust a dimensional characteristic of the elongate element may be suitable for use in connection with the disclosed embodiments.
As shown in
As shown in
As shown in
Some embodiments of the occlusion device system provided herein can treat multiple endovascular occlusion sites during a single treatment session. For example, the delivery catheter can be positioned at a first endovascular location and can deliver one or more segments of elongate element material to occlude a first occlusion space (e.g., a first aneurysm). Then, without removing the delivery catheter from the patient, the catheter can be repositioned to a second location and can deliver one or more elongate element material segments to occlude a second occlusion space (e.g., a second aneurysm). If desired, a third space can be treated (again, without removing the delivery catheter from the patient), and so on.
The elongate elements can be deployed to an occlusion site in the following manner. The elongate element 134 can be deployed to the occlusion site as the leading-end of the combined elongate elements. As the elongate element 134 exits the delivery catheter (not shown), the elongate element 134 can create a generally spherical outer frame as depicted in
As the elongate element 132 exits the catheter, it can begin to fill the volume defined within the elongate element 134 outer framework. As shown in
In some embodiments, the carrier 143 can be a looped material. The conveying portion 144 can be in contact with the elongate element 142. In some embodiments, the elongate element 142 can be tacked to the conveying portion 144 of the carrier 143 to assist the elongate element 142 to move through the catheter's first lumen in conjunction with the conveying portion 144. The movement of the carrier 143 can be induced by the application of a tensile force acting in the direction of arrow 148. That is, the returning portion 145 can be urged in the direction of arrow 148 to cause the entire length of carrier 143 to move with respect to the catheter, and to convey the elongate member 142 into the occlusion space.
When a portion of the conveying portion 144 of the carrier and the elongate element 142 reach the distal tip of the catheter, the carrier loops back into the second lumen of the catheter, separating from the elongate element 142, and the elongate element continues on into the delivery site in the direction of arrow 146. Carrier 143 may make about a 180-degree turn and reenter the catheter via the second lumen in the direction of arrow 148.
The elongate element of the present invention may also be surgically implanted and activated in situ. Further, the elongate element may be incorporated into an implantable prosthesis.
Hydraulic or mechanical approaches may be used to deliver the elongate element(s), whether it is delivered over or out from within a catheter. For example, hydraulic agents can be used to propel the elongate element through a lumen of a delivery catheter. In the case of hydraulic approaches, various liquids such as saline, radio-opaque contrast or a block copolymer, as described herein, are preferably although not exclusively used as the propelling agent. Hydraulic delivery can be generally performed by pressurizing the proximal end of a lumen containing an elongate element. The pressure can cause the elongate element to be propelled distally, and into the occlusion space. This delivery technique can be enhanced by sealing the interface between the elongate element and the walls of the lumen. Various elongate element design features can provide an enhanced seal between the elongate element and the walls of the lumen. For instance, the auger configuration illustrated in
In example embodiments, the elongate element is imbibed with a first reagent and a second reagent is used to hydraulically deliver the elongate element. A resulting gel or other product may, or in other embodiments, need not be, isolated within the elongate element.
In some embodiments, and with reference to
In some embodiments, and with reference to
The elongate element may be sealed at one end in a variety of manners, as shown in
As noted above, example embodiments comprise a distensible elongate element 100, which may find particular utility in applications where a larger version occlusive device is required, as shown in
Yet another possible delivery system is illustrated in
In some example embodiments, central lumen 119 is used for delivery of the guidewire, yet central lumen 119 may additionally or alternatively be used for delivery of an elongate element or alginate solution. In addition, tube delivery may be combined in this delivery system, including the possibility of deploying a tube by filling it with an elongate element.
The operational concept, as provided in reference to
The distal-end delivery lumen of the distal catheter 112 can be selectively coupled with individual dispensing lumens of the multiple lumens 113 to dispense segments of elongate element from the dispenser 111. For example, in some embodiments the dispenser 111 can be selectively rotated about its longitudinal axis in the direction depicted by arrow 110. As the dispenser 111 is rotated, the distal catheter 112 remains stationary with respect to the dispenser 111. In this manner, any one of the multiple lumens 113 can become individually selectively aligned and in fluid communication with the distal-end delivery lumen of the distal catheter 112, to be positioned to dispense its segment of elongate element to the distal catheter 112. In other embodiments, the proximal multi-lumen dispenser portion can have a non-cylindrical configuration. For example, the dispenser 111 can have a linear configuration such that the axes of the multiple dispensing lumens are arranged on a common plane. In that case, the dispenser portion would be linearly movable to individually align its dispensing lumens with the distal catheter. In another embodiment, the multi-lumen dispenser portion can have a rectangular configuration. In that case, the dispenser portion would be movable in two planes (e.g., x-y axes) to align its dispensing lumens with the distal catheter. In addition, other embodiments can have other variations of dispensing lumen configurations, such as ovals, helixes, and polygons.
The individual lumens 113 of the dispenser 111 can contain and dispense segments of elongate elements with disparate lengths (e.g., 1″, 2″, 3″, 4″, 6″, 8″, 10″, 1′, 2′, 3′, or greater). The dispenser 111 can include one or more of indicators 114, 116, and 117 that are visible to the clinician operator. These indicators 114, 116, and 117 correspond with individual dispensing lumens of the multiple lumens 113. By knowing what particular segments of elongate material are contained within the individual dispensing lumens, the indicators 114, 116, and 117 can be correlated with the lengths of the elongate element segments housed within the dispensing lumens. In this manner the clinician operator, knowing which individual dispensing lumen is coupled with the distal catheter 112, can be apprised of what segment length of elongate element the multi-lumen portion is configured to dispense, in some implementations. The indicators 114, 116, and 117 can be used to identify various properties pertaining to an individual dispensing lumen. For example, among other things, the indicators 114, 116, and 117 can identify a dispensing lumen number, a segment length of elongate element contained in a dispensing lumen, or a volume of occlusion space that can be filled by the segment of elongate element contained in a dispensing lumen. In some embodiments, at least the proximal end of the dispenser 111 is positioned outside of the body of the patient being treated. In some embodiments, the junction of the dispenser 111 and the distal catheter 112 is positioned outside of the body of the patient being treated.
In certain embodiments of an endovascular occlusion system, the elongate element may be delivered along with a balloon, for example with a dual-lumen catheter. In a preferred embodiment, a balloon is delivered along with the elongate element in its first configuration to a treatment site, whereupon both are deployed and the balloon remains deployed where occlusion is not desired until the elongate element has assumed its second, activated or reacted (e.g., cross-linked) configuration where occlusion is desired. The balloon may then be retrieved.
In some embodiments where the elongate element comprises a tube, a coil or a plurality of coils may be delivered into the tube, and delivery of the coil or coils may cause the tube to be deployed into an occlusion site.
Related methods are also contemplated herein and may be used in connection with occlusion of aneurysms of all sizes (e.g., intracranial and aortic aneurysms), vessels of all sizes, venous and arterial, sequestration of diseased tissue, and endoleaks, to name just a few applications. The present invention may also be used in connection with the unwanted retrograde infusion associated with the delivery and deployment of endovascular devices.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
By way of non-limiting example, while the present invention has been described primarily with reference to the cardiovascular system, those skilled in the art will appreciate that the invention is not so limited, but may have utility more broadly wherever filling or occlusion is required. The present invention may also have applicability as an implantable/removable drug-elution reservoir.
Any patents or publications referred to herein are hereby incorporated by reference herein in their entirety.
This application claims priority to U.S. Provisional Application No. 61/515,753, filed Aug. 5, 2011. The disclosure of the prior application is considered part of (and is incorporated by reference in) the disclosure of this application.
Number | Date | Country | |
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61515753 | Aug 2011 | US |