US20160166372A1 - Ivc filter retrieval systems with interposed support members - Google Patents

Abstract

Funnel-trap type delivery and/or retrieval devices for Inferior Vena Cava (IVC) filters or other medical implants are described in which the devices comprise two layers of braid with an axially support member. The support member may be interposed between braid layers or set inside the braid layers but interposed between heatset features. Delivery and/or retrieval devices, kits in which they are included, methods of use and methods of manufacture are all contemplated herein.

Description

RELATED APPLICATION
• This application claims the benefit of and priority to U.S. Provisional Patent Application Ser. No. 62/091,433 filed Dec. 12, 2014, which is incorporated by reference herein in its entirety and for all purposes.
FIELD
• The embodiments described herein relate to endovascular temporary Inferior Vena Cava (IVC) filter, other implant or other foreign body retrieval devices or system and methods.
BACKGROUND
• Temporary IVC filters are placed much like permanent filters, but are designed so that they may be retrieved in a separate endovascular procedure, generally from a femoral vein or internal jugular vein approach. Most of the currently available temporary filters include a hook-like feature with which they can be captured and received within a catheter or sheath for removal by employing a gooseneck snare or a multi-loop snare.
• While retrieval is a simple procedure in principle, difficulty is often encountered capturing a filter's hook with the snare loop(s). Such difficulty is compounded when the filter is tilted or off-kilter in placement. Several filters are designed to avoid such orientation. However, the problem remains common because the device is not anchored into the IVC in a stable fashion. Constant blood flow in addition to blood clots can disorient the filter within the IVC making recapture difficult.
• Accordingly, there exists a need for a filter retrieval system with improved ease of use and/or less susceptibility to problems of filter orientation.
SUMMARY
• Embodiments hereof meet this need and others as applied to other medical device applications. For IVC filters, the subject systems may be used with a wide variety of filter architectures—existing or otherwise. Accordingly, new filters may be designed for use with the subject retrievers in which fewer design constraints and/or compromises may be required of the filter design. Features of the subject system may be used in connection with existing and/or modified versions of the filters described in any of U.S. Pat. Nos. 3,952,747; 5,601,595; 6,443,972; 7,338,512 and 7,625,390 (all of which patents are incorporated herein by reference in their entireties for any purpose), with commercially available devices including the OPTEASE, GÜNTHER TULIP, CELECT and OPTION or others.
• In the subject embodiments, one or more members are interposed between braid layers defining a funnel trap in the subject device. In one embodiment, the support member may resemble a flower. The support member may comprise a polymer, Nitinol (superelastic at body temperature or below) or other metal or alloy. Especially when the “flower” comprises a thermoplastic material or Nitinol, the “petals” of the so-called flower may be heatset flat at appropriate temperatures as understood by those with skill in the art. In another embodiment, the support members are independent and stabilized between layers of braid as having a hook or “J” shape. These may be originally cut from flat stock or a tube of polymer or metallic material. Such member may be further stabilized by suture loop(s) through or around each such member or body. Advantageously, any knot securing the suture can be positioned within the interior of the funnel trap section of the device. This can be accomplished by tying the knot(s) on the outside and then pivoting the trimmed structure through the braid from which the device is constructed.
• In the so-called flower embodiment, a single such member may be used. It may be advantageously cut with four strips, slats, leaflets or petals—collectively, “support elements.” More cuts may be made (e.g., with a blade or laser) to define a greater number of elements. However, since it is advantageous for these members to have a large width-to-thickness ratio to avoid lateral displacement when cycling the funnel trap between open and closed (or vice-versa) it may instead be desirable to double-up one flower member with another in a slip or press fit or other telescoping fashion. So paired (or tripled), leaflet or petal width can be maintained while their number is increased.
• With this embodiment, the flower also has a shaft. This is typically received over an inner layer of the funnel trap braid. But it can also be positioned inside the inner layer and abut the distal fold of the funnel trap extension. A proximal end of the shaft may be abutted by a heat shrink, glued or fused-on tube to maintain stability without increasing proximal profile. With the flower overlaid by a/the outer braid layer of the funnel trap structure, the entire assembly may be secured by an outer jacket of heat shrink of fused-on polymer layer. Suitable shrink and/or fusing materials include PTFE, FEP, PEBAX, PEEK or others. Adhesive bonding may alternatively be employed.
• In the so-called J or hook-shaped embodiment, for proper recapture, it is important that the proximal end of the support members are able to float between the layers. This is so because of the way in which the angles of the braid change during compression. Accordingly, any suture securing the members in position relative to the braid that pass through the members should be located distally. Any proximal stabilization features should be looped around the members to allow translation or slipping.
• The former embodiment (i.e., with the flower) may also use lateral stabilization features. However, in this embodiment, the proximal “shaft” of the flower is fixed or pinned with the braid and the braid should slide or translate past the distal end of the leafs or petals. As such, any distal petal stabilization features should be of the loop-type described above in this region.
• Other approaches as further shown and described may be employed in support member construction. Examples include laser-cut tubular bodies. Generally, these will be elastic (e.g., as produced in polymer) or superelastic (e.g., as cut from Nitinol hypotube). Such members may be cut in a compressed or collapsed configuration and then plastically or thermally (i.e., as in heatsetting) formed to an expanded shape and then so-assembled with the device embodiment braid. Various optional constructions and construction techniques are detailed below. So-too are different braid layer assembly options.
• The subject delivery and/or retrieval devices, kits in which they are included (with and without assembly), methods of use and manufacture (including assembly of the constituent components in vivo or ex vivo) are all included within the scope of the present disclosure. Some aspects of the same are described above, more detailed discussion is presented in connection with the figures below.
• Other systems, devices, methods, features and advantages of the subject matter described herein will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, devices, methods, features and advantages be included within this description, be within the scope of the subject matter described herein, and be protected by the accompanying claims. In no way should the features of the example embodiments be construed as limiting the appended claims, absent express recitation of those features in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
• The details of the subject matter set forth herein, both as to its structure and operation, may be apparent by study of the accompanying figures, in which like reference numerals refer to like parts. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the subject matter. Moreover, all illustrations are intended to convey concepts, where relative sizes, shapes and other detailed attributes may be illustrated schematically rather than literally or precisely.
• FIGS. 1A and 1B picture IVC filter variations as may be used in the present system.
• FIG. 2 is a side view of a delivery and/or retrieval system with an end of any type of implantable medical device or foreign body.
• FIG. 3 is a side-sectional view of a converted preform (i.e., a finally shaped funnel section of the subject device) after heatsetting.
• FIGS. 4A-4D are side sectional views illustrating an assembly approach with the subject interposed support member(s).
• FIGS. 5A-5D are side-sectional views illustrating interposed support member assembly options and features.
• FIG. 6A is a perspective side view one support member in an as-cut or compressed configuration;FIG. 6B is a side view of a/the support member heatset in a splayed and flattened configuration.FIG. 7 is a perspective view of tooling for heatsetting a support member as shown inFIG. 6B.
• FIG. 8A is a top view of an open support member;FIG. 8B is a top view of paired support members.
• FIG. 9 is an assembly view illustrating support member construction according to heat-shrink material based approach.
• FIG. 10 is another assembly view illustrating support member construction with separate elements.
• FIG. 11 is a side-sectional view a system including a shaft-based support member.
• FIG. 12A is a side view of another support member embodiment;FIG. 12B is an assembly view of elements as shown inFIG. 12A.
• FIG. 13 is an end view of an embodiment constructed with the assembly inFIG. 12B.
DETAILED DESCRIPTION
• Various exemplary embodiments are described below. Reference is made to these examples in a non-limiting sense, as it should be noted that they are provided to illustrate more broadly applicable aspects of the devices, systems and methods. Various changes may be made to these embodiments and equivalents may be substituted without departing from the true spirit and scope of the various embodiments. In addition, many modifications may be made to adapt a particular situation, material, composition of matter, process, process act(s) or step(s) to the objective(s), spirit or scope of the present invention. All such modifications are intended to be within the scope of the claims made herein.
• Before the present subject matter is described in detail, it is to be understood that this disclosure is not limited to the particular example embodiments described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present disclosure will be limited only by the appended claims.
• All features, elements, components, functions, and steps described with respect to any embodiment provided herein are intended to be freely combinable and substitutable with those from any other embodiment. If a certain feature, element, component, function, or step is described with respect to only one embodiment, then it should be understood that that feature, element, component, function, or step can be used with every other embodiment described herein unless explicitly stated otherwise. This paragraph therefore serves as antecedent basis and written support for the introduction of claims, at any time, that combine features, elements, components, functions, and steps from different embodiments, or that substitute features, elements, components, functions, and steps from one embodiment with those of another, even if the following description does not explicitly state, in a particular instance, that such combinations or substitutions are possible. Express recitation of every possible combination and substitution is overly burdensome, especially given that the permissibility of each and every such combination and substitution will be readily recognized by those of ordinary skill in the art upon reading this description
• FIG. 1A shows a GÜNTHER TULIP (Cook Medical, Inc.)temporary IVC filter10 with ahook12 end interface for retrieval. As shown inFIG. 1B for anIVC filter20, the hook may be modified or substituted for a nubbin-type interface22. The nubbin (itself) may comprise a laser-formed or solder-formed protuberance or bump24 on anextension26 from ahub28. Alternatively, as shown inFIG. 2, a/thefilter retrieval interface22 may comprise aband24′ (e.g., a Pt marker band) mounted (e.g., by swaging, welding, gluing, etc.) on a/theextension26. However the enlargement is created, the funnel-trap structures described below are adapted to secure that feature for IVC filter retrieval.
• FIG. 2 provides an overview of thesubject system100. A funnel-trap structure30 is shown made ofheatset braid material32. The construction provides a flexible distal extension to anelongate shaft34. The shaft is received within an elongate sleeve50 (that may be a commercially available catheter or a custom part of the overall system100) and may include a distalradiopaque marker band52.
• The braid may comprise Nitinol (preferably that is superelastic at body temperature), CoCr, Stainless Steel or another biocompatible material. It is advantageously braided material incorporating between 72 and 288, or between about 144 and 192 filament “ends” in a 1-over-1, 1-over-2, 2-over-2 or other pattern. With (superelastic) Nitinol, the wire is advantageously between about 0.001 and about 0.003 inches in diameter. In which case, a supple and relatively “smooth” matrix surface is provided from which to construct the flexible funnel-trap architecture shown and described. The value of such a surface is in its atraumatic aspect and/or ability to help guide in IVC filter interface into position for capture even if it is oriented off-angle. Still, other wire size and/or end count in a braid or other construction options are possible as well.
• To further assist with recapture, thefunnel trap structure30 may be selectably directable. As indicated by the arrows inFIG. 2, the material from which it is made can be heatset or otherwise configured to provide a bias in an angular direction. The angle of deployment may be selectable or fully straightened by relative position of a core member or obturator (not shown) or by a sleeve or catheter sheath as further described. Further positioning may be achieved by rotating the device as further illustrated. Alternatively, a curved, “L” or “J” shaped wire may be received within a lumen ofshaft34 that can be passed up to and/or through to the inside of the funnel trap structure. Made of superelastic Nitinol (or other) wire, this member can be used to selectively shape or direct the device end.
• Other device articulation options for selecting the angular orientation of the funnel-trap portion of the device are possible as well. Any of a variety of steerable or directable catheter-type technologies (reliant on pull-wires or otherwise) can be incorporated inshaft34 for such purposes. Examples include the mechanisms described in U.S. Pat. Nos. 4,723,936; 4,960,411; 6,251,092 and 8,273,073, each incorporated herein by reference in its entirety, for such description.
• The subject “funnel trap” may be generally frusto-conical in shape as shown or otherwise configured. With an outer conical shape (i.e., a triangular shape in cross section as shown) the structure is highly supportive for any necessary or desirable tissue discretion that might need to occur to free an emplaced filter. Moreover, such a shape provides a flexible “waist”section48 for the directable feature(s) noted above. Still, the device may be bowed outward along its sides or otherwise configured without departing from claimed inventive aspects or variations.
• Importantly, the distal rim opening40 of the structure is larger than the more proximal rim opening42 to operate in guiding filter engagement feature(s) orenlargement24/24′ into a pocket (P) where it is captured and subsequently locked upon advancingsleeve50.
• Such a pocket is formed betweenbraid walls44 andbend38, optionally serving as an abutment feature with an edge or shoulder of nubbin/bump24/24′. To ensure capture, thesleeve50 may be advanced fully overtrap30 before withdrawal into a separate catheter. In other words, advancingsleeve50 overfunnel section30 “closes the trap” and securely captures the implant to be retrieved. Otherwise, the sleeve may be a catheter.
• Notably,system100 may be used identically when capturing afilter10 with atypical hook end12. However, the additional bulk/lateral extension of the hook may necessitate use of a relatively larger sleeve orcatheter50. In any case, system use may be visualized fluoroscopically by a physician by way of marker features24/24′ and52 and/or others as may be conveniently provided.
• In the various system architectures, the catheter/pusher shaft and/or sleeve may comprise a simple extrusion (e.g., PTFE, FEP, PEEK, PI, etc.) or may be constructed using conventional catheter construction techniques and include a liner, braid support and outer jacket (not shown), metal hypotube, etc. Further, the filter frame may be constructed using conventional laser cutting and electropolishing techniques and/or be otherwise constructed. In embodiments intended for tracking through a guide/delivery catheter without an incorporated sheath, a loading sheath may be employed. Advantageously, any such loading sheath is splittable. Other typical percutaneous access instruments (such as wires, etc.), valves and other hardware may also be employed in connection with the invention embodiments.
• The funnel-trap structure30 may be made as a subassembly and attached to the catheter/pusher shaft. PCT publication PCT/US2014/042343 (WO2014201380) and U.S. patent application Ser. No. 14/569,500, each incorporated by reference in its entirety, detail optional steps in the manufacture of a pre-form for constructing the funnel-trap portion of the final device as shown ifFIG. 3.
• For IVC filter retrieval, the funnel-trap portion30 shown may have a diameter (D) from about 5 mm to about 20 mm, or more preferably about 10 to about 15 mm (i.e., size in a range to work within average size human IVCs where such vessels are reported as having a mean diameter of 20 mm within a range of 13 to 30 mm). A length (L) may range from about 10 mm to about 30 mm. An overall cone angle (α) betweenbraid walls44 may be between about 30 and about 90 degrees. An angle (β) ofbend36 betweenbraid wall44 andflap46 may be between about 0 and about 60 degrees and flap length (F) may be between about 1 and about 10 mm in length. Overall, a funnel trap opening diameter (d) may be between about 5 and about 95 percent of diameter (D) depending on the selected combination of the noted variables (i.e., d, D, L, F, α and β). At the lower end of this range, the inner “opening” may be substantially closed such that it must be pushed-open to receive the proximal engagement feature(s) of the implant during retrieval. At the higher end of the range, the flap may lie completely along or in-line with the outer layer(s) of the device. Theopening40 of the funnel trap may be set at 90 degrees relative to a device axis as shown. Otherwise, it may be angled or have a more complex shape as described in connection withFIGS. 9-13 in the above-referenced U.S. patent application Ser. No. 14/569,500, incorporated herein by reference.
• Embodiments hereof include a support member or support members set within the funnel trap section or portion of the device. The support member(s) may be interposed between braid layers or set inside the braid layers but interposed between heatset features.FIGS. 4A-4D illustrate an approach to producing the former construction and a method of manufacture.
• Here,braid32 is manipulated (inFIG. 4A) flipping an outer layer (OL) over and then back (inFIG. 4B) upon an inner layer (IL) withsupport member60 placement and abutment by a locatingfeature110 in the form of shrink tubing. The braid layers are re-aligned and shrinktubing110 reduced in diameter by applying hot air inFIG. 4B. InFIG. 4C,funnel trap structure30 is mounting onpusher member34 using anotherjacketing shrink sleeve112. InFIG. 4D, a final system assembly is shown with anouter sleeve50 and optionalproximal catheter jacket114 comprising PTFE shrink or other material.
• FIG. 5A provides an enlarged view of thefunnel trap30 plussupport structure60 shown inFIGS. 4A-4D. Here, the two-layer (IL and OL) construction of thetrap30 formed byheatsetting braid32 is more apparent. In this cross-section view, two “petals” 1, 3 of thesupport structure60 “flower” are shown as well. In this example of a four-petal support member embodiment, petals (which would otherwise be numbered 2 and 4) into an out of the plane of the figure are not show. A section of a cylindrical base orshaft62 ofsupport structure30 is, however, shown in cross-section.
• FIG. 5B illustrates another support structure embodiment. Hereseparate support member70,72 “fingers” that are curled or hooked over into “J” shapes are independent of one another and stabilized between layers of braid. (As per the convention inFIG. 5B, the fingers into and out of of the page of the cross-section view are not shown.) Such member(s) may be further stabilized by suture loop(s) passing through and/or around each such member or body with knot(s)74 securing the suture positioned within the interior of theouter walls44 of the device.
• The sutures may be looped around a single member and interwoven through the braid to form a guide or way. In another approach, the suture is formed in a ring around the circumference of the braid between its layers (an option indicated by the dashed-line loops76 in the figure) and tied to each member. Such a tie or knotting approach may be facilitated by forming various locator-type through holes in themember72,74, etc. as by laser cutting, hypotube drilling or otherwise. An example of such an approach is shown inFIG. 11 (although in different context).
• InFIG. 5C, asupport member60 as described inFIG. 5A is placed within thefunnel trap structure30 inside its wall(s)44. As such,petal number2 is visible in the figures and extends like the others toadjacent fold36 to support opening rim40 (as indicated by dashed line).
• In some ways, the support member placement inFIG. 5D resembles that inFIG. 5A; in other ways it is like that inFIG. 5C. The distinction between the embodiments lies in thatFIG. 5D shows afunnel trap construction30′ incorporating two funnel trap preforms30aand30b. Thus, it may be said that theFIG. 5D construction takes the approach inFIG. 5C and adds a second, inner funnel trap to the construction. Alternatively, theFIG. 5D construction may be viewed as a doubling-up of layers relative to theFIG. 5A approach.
• Regardless, the detail view inFIG. 5D includes five layers (A-D) of material. As shown, layer “C” identifies a/thesupport member60 layer. However, other layers combinations are possible, as in an A-C-B-DE combination (i.e., moving thesupport member60 ormembers72,74, etc. outward one layer), A-B-D-C-E (i.e., moving the support layer inward one layer) or A-B-D-E-C (i.e., moving the support layer inward two layers). However the support is received, the doubled-up funnel30′ approach (i.e., withsubassemblies30aplus30b) may offer benefits when lower braid end counts or smaller diameter wires are desired in a given layer while maintaining overall braid density.
• FIGS. 6A and 6B andFIGS. 8A and 8B detail methods of manufacture for certain support member embodiments.FIG. 6A is a perspective side view one support member in an as-cut or compressed configuration. InFIG. 6A, a tube (e.g., PET, PTFE or PEEK) is cut with four slits or slots to define asupport member60 fourpetals1,2,3,4 leaving an interconnected support base orsleeve62. The cutting may be done with a blade or laser cutter. Use of a laser will facilitate the addition of optional stress-relief features64 (dotted line) at the petal junctions as well.
• When cut in metal such as Nitinol, the relief features64 may be necessary. In plastic, they are not. In either case, the body shown inFIG. 6A is advantageously heatset in a splayed-out form as shown inFIG. 6B. This can be accomplished in connection withtooling80 as illustrated inFIG. 7 and a heatsetting or annealing oven. The tooling may comprise a shaft orrod82 to center the support member shaft orsleeve62 andwashers84a,84bfor compressing petals1-4 flat.
• FIG. 8A provides a top view of asupport member60 so-set. With the material heatset open and flat (or set in an approximately conical shape), the structure assists the resiliency of thebraid32 in opening thefunnel trap structure30 upon deployment.FIG. 8B illustrates how afirst support member60acan be nested with asecond support member60bto form a combinedsupport member60′.
• In this case, the nesting doubles the number of support petals. The approach (i.e, nesting of at least two support member sub-assemblies) offers a maximum number of petals, with maximum possible pedal width each (as compared to cutting more petals out of a single tube). The maximized width may be particularly useful in providing lateral stability for the elements when constructed of thin material (e.g., on the order of 0.002 to about 0.005 inches thick) and/or avoiding pushing or poking through the braid the members are intended to support.
• FIG. 9 illustrates still another approach to support member construction. Here, asupport120 is constructed using tubing (e.g., PET or PEEK heat shrink) that is heat shrinked or formed onto amandrel130. Acylindrical portion132 of the mandrel provides around interface portion122 of the support for mounting to thedevice shaft34.Flats134 on the mandrel result in flat portions orpetals124 in the support. When originally formed by heat shrinking on the mandrel, the petals are connected. However, they are cut with shears, a razor blade or otherwise along squared edges (dashed lines) formed byedges136 of the mandrel.
• One such support may be used in a construct as described above. Otherwise a pair (or more) may be nested concentrically. When stacked or nested, as before, the petals are advantageously offset from one another. A symmetrical offset of 45 degrees is advantageous for support members each including four petals, thus providing a combined structure with eight symmetrically arranged support petals. With a support member formed with three petals to be nested with another to form a final construct with six petals, the offset between each petal is advantageously 60 degrees.
• Also, it is possible to plastically deform and set the petals splayed outwards. In a heat-shrink embodiment, it should be done mechanically (i.e., without significant heating), in order to avoid inadvertent (mis)shaping by unintended recovery of the heat shrink tubing. Nevertheless, when two support bodies are employed in a concentric arrangement, they may heat-staked together using a soldering iron tip by cross-wise penetration (or otherwise joined, e.g., by adhesive wicked between the bodies) in order to maintained the desired spacing of petals or for any other reason. The same approach (i.e., heat staking, etc.) may be employed in connection with theFIG. 8B embodiment as well.
• FIG. 10 illustrates yet another approach to support member construction. Here, asupport140 is constructed either on the end of a shaft34 (as shown) or as a separate subassembly to be used like other examples above. Either way, the support comprises a plurality ofindependent extension members142. These may be formed by die cutting or laser cutting PET, PEEK or another sheet material. And then located as shown onto a support body via guide or eye holes144. The eye holes may be aligned alongaxes146 with wires (wire axes shown) that are removed after affixing the complimentary features (e.g., by gluing, laser welding or fusing by typical catheter constructions techniques or otherwise).
• The construct inFIG. 10 may be employed in the support member nesting approach shown inFIG. 11. Alternatively, atubular shaft34 can be processed such that its distal end is cut into a support member section90 with finger orpetal extensions91,92,93, etc. therefrom. These extensions can be heatset as described in connection withFIG. 7 or into a conical shape using a matching tool or form. For shape or heatsetting purposes, the shaft advantageously comprises PET or PEEK (as such a selection provides a good compromise in strength, machinability and formability) or Nitinol. The cutting may be performed with a laser and include stress relief features96 at a junction of theshaft body34 and extensions. Optional zig-zag end features98 may also be included in the construction. These zig-zag, square-wave or other such engaging features can assist in maintaining stable position of the support member fingers when the braid of rim opening40 is compressed and contacting the same. Notably, the same such features may be included in theFIG. 10 and/orFIGS. 12A and 12B embodiment as shown or others as provided herein.
• InFIG. 11, thefunnel trap embodiment30 also includes an optionalsecond support member60 interposed between its braid layers (IL and OL). Notably, thesupport member60fingers1,2, etc. are advantageously staggered or interdigitated (as in the manner shown inFIG. 8B) withextensions81,82, etc. coordinated to maximize the number of non-overlapping elements and provide uniform spacing of radial support points for openingrim40.
• In such asystem100, theextension section30 may be located as shown and bonded with one or more PEBAX (or other thermoplastic material) layers102 toshaft34. A laser welding approach is also possible—particularly for embodiments in which all elements are made Nitinol although other materials might be employed to the same effect.
• FIG. 12A illustrates a laser cut pattern that may be used for the extension sections of a shaft-cum-support as discussed above. Alternatively, the pattern may define the geometry of aseparate support150 as shown.
• In either case, the shape includes a plurality ofextensions151,152,153 and154 in the form of substantially triangular petals, fingers or leaflets. So-configured, the availabledistal interface area156 of each member to support thefunnel trap braid32 is maximized in size, while minimizing a waist orflexure section158 for each petal. The minimized waist provides space for (optionally) radiused stress relief features160 from a base orstem section160.
• Support member150 may be so-cut from Nitinol tubing or other material. The cut pattern may include an open stress-relief area164 comprising a plurality of curved or otherwise configuredbeams166 withinstem section160. Such a section will serve as one or more windows for flow-through of bonding material (e.g., thermoplastic PEBAX—or other material—as noted above) without significant increase in stiffness across theentire base160 of the structure. Alternatively, square or rectangular shaped windows may be provided for bonding. In either case (i.e., with complex, curved windows or rectilinear forms), the windows in each base are advantageously set or “clocked” such that theextensions151, etc. are spaced apart as desired when the windows are aligned for bonding material flow-through. A proximal rim orband168 of eachsupport member150,150′ will prevent pull-out from flow-through bonding approach.
• A wide proximal or distal rim or band170 (i.e., as shown) can—in effect—serve as an integrated radiopaque marker to a/the built-up system. As another option, an inner extent or “frame” portion of one or more aligned windows can be laser welded together to stabilizeoverall support member150,150′ position for further assembly processing. Yet another option is to laser or resistance weld proximal or distal rim orband168,170 for such purpose(s).
• Still further, each rim (or an integrated rim without an intermediate stress-relief section or area164) may be split as shown, even if cut from cylindrical tubing. Asplit line172 may be used for nesting one such tube with another. If the kerf or separation of the split line is wide enough, thebase160 may be compressed and fit inside another tube originally of the same size. Alternatively, a split pair may be employed where one contracts and the other expands.
• FIG. 12B illustrates assembly of a pair ofsupport members150 and150′. In this example, neither base is split. Rather, the tubes from which the patterns are cut are sized to nest with each other. Thebase160 of each body may include arelief pattern164 configured to match-up when they are set concentrically with each other and offset (e.g., as suggested by the curved arrow so the so-called fingers or petals do not overlap. Alternatively (as shown), the relief patterns may be configured so that they are non-aligned with the petals offset. Such an approach may provide more uniform flexibility.
• For use,petal extensions151,152, etc. are typically heatset outwardly (as shown) andend interface sections156 may retain the curvature native to the tube from which they are cut. In which case, any included zig-zag end pattern along withinterior relief174 may provide flexibility when opening or deploying the funnel trap device. Otherwise, the interface sections may be heatset flat (or at least partially flat) for one or both of thesupport members150,150′. In which case, the aforementioned flexibility will assist in fully compressing the device for tracking and/or retrieval. Without such a pattern provided, associated part width or thickness may be altered if so-desired.
• With arelief section174, distal interface156 (whether zig-zagged, flat or otherwise configured) portions are shown supported bystruts176. Alternatively,relief space174 may be omitted. Such an embodiment (not shown) may employ a single central strut as part of an overall “T” shaped body.
• In any case,FIG. 13 is an end view of adevice100funnel section30 withsupport members150/150′ set withinbraid material32. It can be observed through the braid that alternating petals X, Y are wider and narrower, respectively. This is a result of cutting maximumwidth interface sections156 from larger and smaller tubing, respectively, for nesting.
• With the split-tube approach, the samesize interface sections156 may be provided. However, upon compression, narrower “Y-type” members may compress better (i.e., to their native tube size) offering a reduced device crossing profile. Stated otherwise, excessive dimensional stack-up can be avoided if a mix of X- and Y-type or sized members are provided. Such a consideration may be of use in minimizing lockingsleeve50 size, if used.
• Variations
• The subject methods, including methods of use and/or manufacture, may be carried out in any order of the events which is logically possible, as well as any recited order of events. Medical methods may include any of a hospital staffs activities associated with device provision, implant positioning, re-positioning, retrieval and/or release.
• Furthermore, where a range of values is provided, it is understood that every intervening value, between the upper and lower limit of that range and any other stated or intervening value in the stated range is encompassed within the invention. Also, it is contemplated that any optional feature of the inventive variations described may be set forth and claimed independently, or in combination with any one or more of the features described herein.
• Though the invention has been described in reference to several examples, optionally incorporating various features, the invention is not to be limited to that which is described or indicated as contemplated with respect to each variation of the invention. Various changes may be made to the invention described and equivalents (whether recited herein or not included for the sake of some brevity) may be substituted without departing from the true spirit and scope of the invention.
• Reference to a singular item includes the possibility that there are a plurality of the same items present. More specifically, as used herein and in the appended claims, the singular forms “a,” “an,” “said,” and “the” include plural referents unless specifically stated otherwise. In other words, use of the articles allow for “at least one” of the subject item in the description above as well as the claims below. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as “solely,” “only” and the like in connection with the recitation of claim elements, or use of a “negative” limitation.
• Without the use of such exclusive terminology, the term “comprising” in the claims shall allow for the inclusion of any additional element—irrespective of whether a given number of elements are enumerated in the claim, or the addition of a feature could be regarded as transforming the nature of an element set forth in the claims. Except as specifically defined herein, all technical and scientific terms used herein are to be given as broad a commonly understood meaning as possible while maintaining claim validity. Accordingly, the breadth of the different inventive embodiments or aspects described herein is not to be limited to the examples provided and/or the subject specification, but rather only by the scope of the issued claim language.

Claims (20)

1. An apparatus for delivery or retrieval of a vascular medical device, the apparatus comprising:

an elongate shaft having an axis having a flexible distal extension comprising braid, the extension folded-back inwardly at a distal opening and forming a more proximal opening, and

a support member comprising a plurality of elongate support elements secured to or within the extension for supporting the extension along the axis,

wherein the proximal opening is sized to receive and pass a proximal end of the medical device therethrough for capture.

2. The apparatus ofclaim 1, further comprising an elongate sleeve receiving the elongate shaft and distal extension to secure the proximal end of the medical device.

3. The apparatus ofclaim 1, further comprising the medical device.

4. The apparatus ofclaim 3, where the medical device is an inferior vena cava filter.

5. The apparatus ofclaim 1, wherein the support member is secured by being interposed between layers of the extension.

6. The apparatus ofclaim 1, wherein the support member is secured without being interposed between layers of the extension.

7. The apparatus ofclaim 1, wherein walls of the extension comprise two layers of braid.

8. The apparatus ofclaim 7, wherein the walls consist of four layers of braid.

9. The apparatus ofclaim 1, wherein the plurality of elongate support member elements comprise a zig-zag distal interface.

10. The apparatus ofclaim 1, wherein the support member comprises two concentric bodies.

11. The apparatus ofclaim 10, wherein the two concentric bodies are offset from one another in angular relation.

12. The apparatus ofclaim 10, wherein one of the two concentric bodies is formed as an extension of the shaft.

13. The apparatus ofclaim 1, wherein the support member is formed in the shaft.

14. The apparatus ofclaim 1, wherein the plurality of elongate support member elements are headset flat.

15. The apparatus ofclaim 1, wherein the support member is not connected to the shaft.

16. The apparatus ofclaim 15, wherein the plurality of elongate support members are J shaped and folded inwardly with the extension.

17. A method of manufacturing a medical device, the method comprising:

forming a section of tubular braid with a first fold;

forming the braid with a second fold adjacent to the first fold to provide an interior flap between the first and second fold; and

inserting an axial support member within the braid layers.

18. The method ofclaim 17, wherein the support member is inserted between the braid layer.

19. The method ofclaim 17, wherein the support member is inserted inside the braid layer and not in-between the braid layer.

20. The method ofclaim 17, further comprising bonding the support member and braid to the shaft with thermoplastic flow through a base of the support member.

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