Vascular filter

Abstract

A vena cava filter apparatus, having a filter body having an upper end portion, lower end portion, and a mesh or woven or braided wall. An upper end collar is connected to the filter body upper end portion. A lower collar is connected to the filter body lower end portion, with the lower collar having an open ended bore. A cable member extends between the collars and at least through the lower collar bore, the lower collar bore having two holes of two different diameters. The cable member has a cable with a cable diameter and multiple spaced apart stops. Each stop is configured to pass through a collar bore. Each stop is configured to engage a collar, wherein when one stop engages the upper collar and a second stop engages the lower collar. The collars can be moved closer together to a deployed position.

Description

VASCULAR FILTERVASCULAR FILTER AND METHODInventor: Neville Chia, Tuas Avenue 2, BDX, Singapore, South West, Singapore 639461. Applicant / Owner / Assignee: Bard Peripheral Vascular, Inc.FIELD OF THE INVENTION

[0001] The present invention relates to a method and apparatus to trap blood clots in a patient's vascular system such as in the inferior vena cava (IVC). The present invention relates to vascular filters that trap or collect emboli that are flowing in a patient's vascular system. More particularly, the present invention relates to an improved vascular filter and method that has a mesh, woven, or braided filter body having an interior, upper and lower collars, and a mesh or braided or woven wall that surrounds the interior and spans between the collars. In one or more embodiments, the apparatus can be an inferior vena cava filter, a coronary stent, an angioplasty balloon, a ureteral stent or flow diverting stent. A specially configured cable extends from one collar to the other collar and through the interior of the filter body, wherein the cable has enlarged diameter stops that enable expansion or contraction of the filter body by changing the position of the stops relative to the collars using surgical tools or implements.GENERAL BACKGROUN D

[0002] Current filters, such as IVC filters, can be difficult to retrieve when placed for a long period of time. On many such filters, the legs (or leg anchors) over time would have driven deep into the vessel wall or even puncture adjacent organs, making retrieval a time-consuming procedure. Punctures from the leg anchors could also lead to internal bleeding, putting the patient at risk.BRIEF SUMMARY OF THE INVENTION

[0003] The present invention provides an improved method and apparatus to trap blood clots in a patient's vascular system (e.g., inferior vena cava (IVC)). The method includes a filter and deployment tools. The present invention provides a better fit to the population range of IVC sizes and contours than current IVC filters having legs with barbed tip ends.

[0004] The present invention provides more contact area along the axis of each and every fiber compared to the current IVC filters. The present invention does not puncture the vessel wall (e.g., IVC) as it does not have barbed tips seen in many current IVC filters.

[0005] The present invention has one proximal filter surface and one distal filter surface instead of one filter surface in current IVC filters. Over a long time (e.g., 90 to 355 days), the vessel wall surfaces will scar and lock onto the fibers of the filter, preventing slippage of the filter. Being flexible, the filter of the present invention is easier to retrieve than the current vascular filters after being placed for a very long time (e.g., 90 to 365 days). The IVC is not a rigid blood vessel, dilating on expiration and constricting on inspiration. This invention conforms easily to the changing IVC due to its flexibility. The above discussed advantages make this invention safer for patients than the current IVC filters.

[0006] The present invention thus provides a vena cava filter apparatus, having a filter body having an upper end portion, a lower end portion, and a mesh, fabric or braided or woven wall. An upper collar is connected to the filter body wall at the upper end portion, with the upper end collar having a first open-ended bore.

[0007] A lower collar is connected to the filter body wall at the lower end portion, the lower collar having a second open-ended bore.

[0008] A cable member extends through the filter body interior between the collars and through each of the upper collar bore and lower collar bore.

[0009] The cable member has a cable with a cable diameter and multiple spaced apart stops, each stop having a diameter that is larger than the cable diameter. Each stop is configured to pass through a collar bore. In certain embodiments, each stop is configured to engage a collar, wherein when one selected stop engages the upper collar and a second selected stop engages the lower collar. The collars can be moved closer together to change the shape of the filter body from an elongated shape (see, for example, Figures 1 and 9-10) to a more compressed shape (see, for example, Figures 14-15, and 27). When fewer stops are in between the collars (e.g., see Figures 15 and 24), the filter diameter is larger in order to engage the vessel wall. When more stops are in between the collars, the filter diameter is smaller (e.g., see Figures 20, 22).

[0010] In one or more embodiments, the present invention relates to a vena cava apparatus wherein each stop is an enlarged spherical element.

[0011] In one or more embodiments, the present invention relates to a vena cava apparatus wherein the upper collar and stops are deformable relative to each other.

[0012] In one or more embodiments, neither the collars nor the balls / stops / protrusions are deformable. In such embodiments, the placement of the filter can rely upon a locking mechanism of the collar wherein the collar has a divider / keyhole with two openings, one large enough for a ball to be pulled through and one small enough so that the ball cannot return to the other side of the divider / keyhole.

[0013] In one or more embodiments, the present invention relates to a vena cava apparatus wherein the lower collar and stops are not deformable relative to each other.

[0014] In one or more embodiments, a first open ended bore can have multiple sections of differing diameter (e.g., see Figure 5). In this way, a stop which has a larger diameter than the diameter of the upper section can abut the upper collar and prevent the filter from extending in an upward direction.

[0015] In one or more embodiments, the present invention relates to a vena cava apparatus wherein a second open ended bore has a conically shaped portion. The second open ended bore thus can have a variable diameter or tapered shape (e.g., see Figure 8).

[0016] In one or more embodiments, the present invention relates to a vena cava wherein the second open ended bore has a frusto-conically shaped portion.

[0017] In another set of embodiments, the present invention comprises a collar which is much longer on its axis than the diameter.

[0018] In one or more embodiments, the present invention includes a collar which is non- compressible and balls / stops / projections which are non-compressible.

[0019] In one or more embodiments, the present invention includes a cable member with stops which can be pulled through a keyhole in a lower collar, wherein the cable member, once pulled through the keyhole of the lower collar (once a stop is pulled through), cannot move back through the keyhole, effectively preventing the filter from returning to a fully elongated state.

[0020] In one or more embodiments, the present invention includes both an upper collar and lower collar with keyholes, wherein the cable member and stops can be pulled through the lower collar or upper collar, or both.

[0021] In one or more embodiments, the present invention includes a lower collar which allows a cable member to be pulled proximally, away from the body of the filter, said cable memberpossessing a plurality of stops which allow the filter to be locked into an expanded configuration, to various degrees.

[0022] In one or more embodiments, the present invention has an upper collar which does not allow a cable member to be pulled through it. In such embodiments, the cable member is fixedly attached to the upper collar member.

[0023] In one or more embodiments, the present invention relates to a vena cava apparatus wherein the cable has a diameter of between 0.35 and 1.0 mm.

[0024] In one or more embodiments, the present invention relates to a vena cava apparatus wherein each stop has a diameter or thickness of between 0.8 and 2.0 mm.

[0025] In one or more embodiments, the present invention relates to a vena cava apparatus wherein the first open ended bore has a maximum bore diameter of between 0.5 and 1.2 mm.

[0026] In one or more embodiments, the present invention relates to a vena cava apparatus wherein the second open ended bore has a maximum bore diameter of between 1.0 and 1.6 mm and a minimum bore diameter of between 0.4 and 1.4 mm.

[0027] In one or more embodiments, the present invention makes it possible to utilize advanced drug-eluting materials (such as paclitaxel) that afford additional advantages. For example, drugs that are slowly released from the braid through drug-eluting properties may advantageously have clot dissolving properties, improving the filter effectiveness in containing blood clots and ensuring normal blood flow is unimpeded through the filter. The second advantage is that the presence of a drug being eluted from the IVC filter is an indication and predictor of the useful life of the filter. Accordingly, doctors can monitor and forecast time for prompt removal of the IVC filter within the filter's useful life.

[0028] In one or more embodiments, the present invention enables use of resorbable fibers that are softer than Nitinol wires of current IVC filters.

[0029] In one or more embodiments, the braided filter comprises individual fibers which are flexible and not like nitinol, the dominant material for IVC filters.

[0030] In one or more embodiments, the present invention enables use of drug eluting properties in the bio-resorbable material fibers to dissolve blood clots.

[0031] In one or more embodiments, the present invention provides potential for the biomaterial fibers to be bioresorbable, removing the need to retrieve the filter and saving costs for patient.

[0032] Other than nitinol, a metal, a type of plastic called biomaterials are also suitable for implantation in the human body and are not rejected by the body.

[0033] Another advantage of the present invention over the prior art is the material of the present invention could also be drug eluting for clot-preventing around the site for a duration of weeks to a few months.

[0034] In one or more embodiments, the present invention comprises material could be seen under ultrasonic or x-ray imaging, during the procedure.

[0035] Yet another advantage is that the risk of nitinol wires spearing the blood vessels is removed totally.

[0036] In one or more embodiments, the stretching and expansion action of the present invention changes the diameter of the tube, which is used advantageously in this invention. This can be seen in Figures 35, 36. The braided wall of fibers conforms to the IVC walls during the whole cycle of dilation and constriction, with each fiber re-arranging itself without encumbrance from adjacent fibers, keeping their positions relative to each other within the braid matrix. All this while, the cable member does not change in length between the collars. This shape shifting property of the braided wall enables the filter to conform to the dynamic contour of the IVC at any one time.

[0037] In one or more embodiments, the braid material can be a biomaterial and may be drug eluting. In certain embodiments, the braided material may be bioresorbable. As it is a braided structure, the fibers are all flexible and able to absorb stress all along the length of the fibers, by twisting and having a radius at all bends. High stress points like a sharp bend will not stay sharp for long, as the braid of multiple strands of wire adjust and reshape itself according to the free space available, like a balloon. Hence, a more uniform stress across all the braids occurs instead of stress concentrated at certain points.

[0038] In one or more embodiments, the apparatus can comprise biomaterials such as Poly-L- lactic acid (PLLA), a synthetic, biocompatible, biodegradable polymer; Polyglycolide (or poly(glycolic acid)) (PGA), a biodegradable, thermoplastic polymer; and / or Polydioxanone (PDO), a biodegradable, synthetic polymer.

[0039] In one or more embodiments, the apparatus comprises a biodegradable polymer.

[0040] In one or more embodiments, the apparatus comprises biomaterials. In one or more embodiments, the biomaterials can be deformable and compressible in a certain direction andyet non-compressible in a different direction. For example, in one or more embodiments, the apparatus comprises a ball and collar wherein the collar is deformable and compressible in the radial direction, but not in the axial direction. In these one or more embodiments, the ball may have a spherical portion and a flat portion, the spherical portion pushing to expand the collar as the cable is pulled in a proximal direction, the flat portion with a diameter larger than the bore of the collar, preventing the stop from returning to its position distal of the collar.

[0041] Due to the ease of retrieval with jugular access and use of a common laparoscopic grasper, this braided IVC filter can, but does not need to be bioresorbable.

[0042] In one or more embodiments, the filter comprises individual braid fibers which are smooth and individually will slip on placement in the IVC. But, when in a braid, the shape formed is able to hold its position along the meandering contours of the IVC wall. Accordingly, the present invention does not solely rely on friction to hold its position.

[0043] As the inferior vena cava dilates or constricts, this braided filter, like an angioplasty balloon, with a longer body than it is wide, with a little flexibility caused by the braided form, will flex and adjust to the contours of the IVC. When the IVC constricts like in a Valsava episode, more of the braids surface area will press on the IVC walls, making the filter more resistant to migration. When the IVC dilates, the braid readjusts to maintain contact with the shifted contour of the IVC. Preferably, the braided IVC filter will be designed with a minimal axial length (longer body) to ensure IVC dilation will not cause a migration.

[0044] In the present invention, a tradeoff is made in terms of allowable blood flow and preventing migration. The allowable blood flow rate can be adjusted by reducing the number of braid fibers, by using innovative weave patterns with fewer fibers, by using thinner fiber crosssections, or by decreasing the filter length to cross-section ratio.

[0045] In one or more embodiments, the present invention comprises a greater filter length to cross-section ratio, (not Figures 14-15, which show a less than 1 ratio) which increases surface contact of fibers, while reducing the overall fiber count (and increasing blood flow) drastically.

[0046] In one or more embodiments of the present invention, nitinol can be utilized, for example. Nitinol, a metal is not deformable and compressible at low forces like using a hand to squash it. But a high force like a hammer strike will deform and compress it. Materials like plastic and metal can both be used in the weave / braid and the balls and the cable.BRIEF DESCRIPTION OF DRAWINGS

[0047] For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:

[0048] Figure 1 is a partial elevation view of a preferred embodiment of the apparatus of the present invention;

[0049] Figure 2 is a fragmentary view of a preferred embodiment of the apparatus of the present invention;

[0050] Figure 3 is a fragmentary side view of a preferred embodiment of the apparatus of the present invention showing the upper collar;

[0051] Figure 4 is a fragmentary top view of a preferred embodiment of the apparatus of the present invention showing the upper collar;

[0052] Figure 5 is a fragmentary sectional view of a preferred embodiment of the apparatus of the present invention showing the upper collar;

[0053] Figure 6 is a fragmentary side view of a preferred embodiment of the apparatus of the present invention showing the lower collar;

[0054] Figure 7 is a fragmentary top view of a preferred embodiment of the apparatus of the present invention showing the lower collar;

[0055] Figure 8 is a fragmentary sectional view of a preferred embodiment of the apparatus of the present invention showing the lower collar;

[0056] Figure 9 is an elevation view of a preferred embodiment of the apparatus of the present invention showing the filter body inside a catheter, the filter in an elongated, pre-deployment position;

[0057] Figure 10 is an elevation view of a preferred embodiment of the apparatus of the present invention showing the filter body in an elongated, pre-deployment position;

[0058] Figure 11 is an elevation view of a preferred embodiment of the apparatus of the present invention showing the filter body in an elongated, pre-deployment position;

[0059] Figure 12 is a sectional view of a preferred embodiment of the apparatus of the present invention taken along lines 1-1 of figure 11;

[0060] Figure 13 is a sectional view of a preferred embodiment of the apparatus of the present invention taken along lines 2-2 of figure 11;

[0061] Figure 14 is an elevation view of a preferred embodiment of the apparatus of the present invention showing the filter body in an expanded, deployed position;

[0062] Figure 15 is an elevation view of a preferred embodiment of the apparatus of the present invention showing the filter body in an expanded, deployed position;

[0063] Figure 16 is a fragmentary view of a preferred embodiment of the apparatus of the present invention showing the cable member;

[0064] Figures 17-18 are fragmentary views of a preferred embodiment of the apparatus of the present invention showing installation tools;

[0065] Figure 19 is a fragmentary view of a preferred embodiment of the apparatus of the present invention showing installation tools;

[0066] Figure 20 is an elevation view of a preferred embodiment of the apparatus of the present invention and illustrating a method of the present invention;

[0067] Figure 21 is a fragmentary view of a preferred embodiment of the apparatus of the present invention showing installation tools;

[0068] Figure 22 is an elevation view of a preferred embodiment of the apparatus of the present invention and illustrating a method of the present invention;

[0069] Figure 23 is a fragmentary view of a preferred embodiment of the apparatus of the present invention showing installation tools;

[0070] Figure 24 is an elevation view of a preferred embodiment of the apparatus of the present invention and illustrating a method of the present invention;

[0071] Figure 25 is a fragmentary view of a preferred embodiment of the apparatus of the present invention showing installation tools;

[0072] Figure 26 is an elevation view of a preferred embodiment of the apparatus of the present invention and illustrating a method of the present invention;

[0073] Figure 27 is an elevation view of a preferred embodiment of the apparatus of the present invention showing a deployed position of the filter;

[0074] Figure 28 is an elevation view of a preferred embodiment of the apparatus of the present invention illustrating removal of the filter;

[0075] Figure 29 is an elevation view of the preferred embodiment of the apparatus of the present invention illustrating removal of the filter;

[0076] Figure 30 is an elevation view showing post removal position of the filter;

[0077] Figure 31 is a fragmentary side view of a preferred embodiment of the apparatus of the present invention showing a collar;

[0078] Figure 32 is a fragmentary cross-sectional view of a preferred embodiment of the apparatus of the present invention showing a collar;

[0079] Figure 33 is a fragmentary cross-sectional view of a preferred embodiment of the apparatus of the present invention showing a collar and a cable member with a stop being pulled in a proximal direction;

[0080] Figure 34 is a fragmentary cross-sectional view of a preferred embodiment of the apparatus of the present invention showing a collar and a cable member wherein the stop prevents the cable member from moving in a distal direction;

[0081] Figure 35 is an elevation view of a preferred embodiment of the apparatus of the present invention showing a deployed position of the filter when the IVC is in minimum dilation inspiration;

[0082] Figure 36 is an elevation view of a preferred embodiment of the apparatus of the present invention showing a deployed position of the filter when the IVC is in maximum dilation expiration;

[0083] Figures 37-39 are elevation views showing retrieval tools of a preferred embodiment of the apparatus of the present invention;

[0084] Figure 40 is a side perspective view of a stop and collar of the present invention;

[0085] Figure 41 is a side perspective view of a stop and collar of the present invention;

[0086] Figure 42 is a side perspective view of another embodiment of a stop and collar of the present invention; and

[0087] Figure 43 is a sectional view of the embodiment of a stop and collar of the present invention shown in Figure 42.DETAILED DESCRIPTION OF THE INVENTION

[0088] Figures 1-30 show a preferred embodiment of the apparatus of the present invention designated generally by the numeral 10. Vascular filter apparatus 10 is configured for placement in a patient's vascular system such as in the inferior vena cava 11. In Figures 3-6, inferior vena cava 11 is shown next to veins 12, 13 (e.g., renal veins). In the drawings, arrows 20 and 46 schematically show the direction of blood flow (see, for example, Figure 10). Vascular filterapparatus 10 has a filter body 14 that has upper end portion 15 and lower end portion 16. Body 14 has a mesh or braided or woven wall 17.

[0089] Upper end portion 15 has an upper collar 18 (see figures 3-5). Lower end portion 16 has a lower collar 19 (see Figures 6-8). In the drawings, the filter apparatus 10 is movable between a first or preliminary smaller diameter (pre-installation) position 22 (Figures 1 and 9-13) and a second or deployed or larger diameter installed position 36 (Figures 14, 15, 27). In the installed or deployed position of Figures 14, 15, 27, any emboli (or other debris) is captured by filter 10 as filter body 14 extends outwardly to contact vessel wall 21. In a deployed position, body 14 thus has a diameter equal to the diameter of vessel lumen 25. Figures 15 and Z1 show a deployed or second position 36. Collar 18 has bore 37 which is open ended (see Figures 4, 5). Bore 37 can include sections of differing diameter as seen in Figure 5. Bore 37 can be uniformly cylindrically shaped, for example. Collar 19 has bore 38 which can be tapered, having frusto-conical section 38 (see Figures 7, 8).

[0090] In order to move the filter body 14 from a first preliminary position 22 to a second or installed or deployed position 36, a specially configured cable member 26 (see Figure 16) is manipulated using tool assembly 40 comprising tool / tube 41, tool / rod 42 and tool / rod 43. Cable member 26 has upper end 27, lower end 28 and multiple projections, balls or stops 30, 31, 32, 33, 34 mounted on wire or cable 35. Although five balls or stops are shown in the figures, the number of balls or stops is not limited to five balls or stops. There could be more or fewer, as desired, as the present invention preferably utilizes a plurality of projections, balls, or stops. Lower end 28 can be provided with a loop 29 (see Figure 16). In an alternative embodiment, the lower end 28 of cable member 26 can terminate in another shape, such as a ball. As long as the lower end can be grasped or connected to a manipulating tool, the lower end can take on a plethora of shapes and configurations. Stops 30, 31, 32, 33, 34 can be deformable / compressible relative to collars 18, 19. Alternatively, collars 18, 19 can be deformable, pliable or expandable. Alternatively, both stops 30, 31, 32, 33, 34 and collars 18, 19 can be deformable. Alternatively, as seen used with collar 119 in Figures 31-34, the collar and stops / balls / protrusions can each be rigid, as in plasticlike. Such material would therefore be compressible and deformable under high force, but not at lower forces, not compressible or deformable. With collar 119, there is no need for the stops / balls / protrusions to compress.

[0091] The apparatus of the present invention has wall 17 that can be constructed with a weave technique (e.g., see Figure 2) and formed into a flexible tube-shaped wall 17 with the ends of thefibers sealed (e.g., heat sealed) to prevent fibers loosening. This tube or fiber wall circumference has physical characteristic of narrowing when the ends are stretched apart (see Figures 1, 9-13, 20, 22) and expanding when the ends are brought together in the axial direction (e.g., see Figures 14, 15, 24, 26, 27). Preferably, the filter body comprises fibers of any material highly resistant to kinking, able to keep its shape, that will be somewhat resilient to bending and flexing. In the braidlike filter body, this group of fibers has memory such that when squeezed in the cross-section or compressed in the axial direction, it will resist lightly and try to return to its original cross-section. However, tightening the cable with the balls overcomes this resilience and increases the force of the fibers against the contours of the blood vessel.

[0092] The filter apparatus 10 is constructed with a plurality of fibers such that there are sufficient gaps or openings 39 between the fibers for the passage of blood, but such gaps or openings 39 are small enough to be able to capture blood clots (e.g., see Figure 2). The amount of blood flow is limited by the density of the braid. The filter apparatus 10 wall 17 is bound tight and attached to each collar. For example, see Figure 27 wherein the wall 17 is attached to collar 119. In this manner, the cable 26 is free to move in the axial direction, through the collar, dictated by the collar embodiment. This cable member 26 has protrusions or stops (e.g., balls, spheres, enlarged diameter portions) 30-34 along its length at fixed positions as seen in Figure 16. The proximal end of the cable 26 can have a loop 29. The lower end of the filter 10 is closed onto the wire just before the loop with lower collar 19. When the filter ends 15, 16 are stretched, the wire loop 29 end is below filter lower end portion 16 (see Figure 20, 22, 24, 26, 27, 28).

[0093] The deployment tool 40 can comprise three components: a flexible thin hollow tube 41 and two assembly rods 42, 43 which are initially housed within the thin hollow tube 41 (e.g., see Figures 17-22). The rods 42, 43 have opposing cutouts 44 (for rod 42), 45 (for rod 43) (e.g., see Figures 17, 18) and can be concentrically aligned or in parallel to each other within the tube 41 (e.g., see Figures 17-26). Rods 42 and 43 can comprise nitinol flat wire. One rod is able to slide in the axial direction that affects the alignment of the two opposing cutouts into a keyhole. Only the distal end of the deployment tool is shown in the drawings. The proximal end of tube 41 (not shown) has an end terminating in a port with finger grips. Tube 41 has a cross section not exceeding the cross section of collar 19, 119. Tools 42 and 43 preferably comprise a pair of Nitinol flat wires with recess profiles 44 and 45. These two tools, 42 and 43, terminate in finger grips that allow the user to slideably manipulate the opening created by the two opposing profiles. Tools 42 and 43 fit slideably into tube 41. Apparatus 10 sits on distal end of tube 41 with cable 26 ensnaredby 44 and 45 recesses and this assembly is delivered to the right location in the IVC by a catheter with cross section that allows passage of the assembly without hindrance. An initial or predeployment position 22 of the filter 10 is shown in Figure 10. Tube 41 engages the lower collar 19 (see Figures 10, 24). Rod 42 recess 44 engages loop 29 and pulls distally, downwardly in the opposite direction of arrow 46. Tube 41 maintains the position of collar 19. As the rod 42 pulls the cable member 26 via loop 29, each stop, projection, or ball 34 (then 33, then 32, then 31) passes through bore 38 of lower collar 19. The collar 19 and / or the ball, stop or projection 30, 31, 32, 33, 34 can be pliable or deformable, allowing it to pass through the bore 38 of collar 19. However, each ball, stop or projection has a diameter larger than the smallest diameter section 47 of bore 38 (see Figure 8), thus preventing the stops from returning to their prior position inside the filter body 14. In Figure 14, balls, projections or stops 33, 34 have passed through bore 38 of the lower collar 19.

[0094] In deploying the filter, catheter 100 is advanced distally to position in the IVC, as seen in Figure 9. Under image guidance, catheter 100 is used to deliver the filter 14 to the desired location. At said location, the IVC is not moved, while the catheter 100 is withdrawn proximally, just sufficient to expose the IVC and tube 40. Catheter 100 has distal end 101 and proximal end 102. Distal end 101 is sized so that the filter 14 can exit the catheter 100 at the distal end. The diameter of the catheter 100 is preferably greater than the diameter of the lower collar 19 of the filter 14. The apparatus 10 sits on distal end of 41 with cable 26 ensnared by 44 and 45 recesses and this assembly is delivered through the catheter 100.The principles of operation of the delivery and retrieval tools 41, 42, and 43 can be seen in Figures 17-26 and 37-39. In Figure 20, the filter 10 can be at a stage of delivery. Figure 19 shows tools 42 and 43 side by side rather than one behind the other as in Figure 20, so that one can see the alignment of the tools 42, 43. Arrow 51 shows the direction of initial movement of tools 42, and 43, during delivery, as their distal most ends are initially housed within tube 41. As seen in Figure 20, filter 10 is not fully deployed as collar 19 is still housed within the tube 14. Tools 42 and 43 are pushed distally until the collar 19 exits the tube 41, as seen in Figure 22. As seen in Figure 22, tools 42, 43 can be pushed in a distal direction, as indicated by arrow 52 in Figure 21. Once the lower collar 19 has exited the tube 41, distally, the cable member 26 can be pulled in a proximal direction, by moving tools 42 and 43 in a proximal direction, as shown by arrow 53 in Figure 23. Cable member 26 is pulled until the desired number of stops / balls / protrusions 30- 34 have been pulled through the lower collar 19. Once the filter body 14 has the desired shapeand tension due to the number of stops pulled through the lower collar 19, the tools 42 and 43 can be used to release the filter in place. As seen in Figures 25 and 26, wherein Figure 25 shows the relative vertical position of tools 42 and 43, tools 42 is moved in a distal direction (see arrow 54) with respect to tool 43. In this way, loop 29 is pushed distally and the lower part of the loop, that which is ensnared in space 45 of tool 43, slides out of the tool 43, thus releasing the filter 10.In Figure 37, by pulling 43 proximally, recess 45 is sliding proximally, with recess 44 fixed. In Figure 38, recess 45 forms a small gap 49 with recess 44 as tool 42 is pulled proximally (in direction of arrow 60) and loop 29 can venture in gap 49. As seen in Figure 39, recesses 44 and 45 close as tool 42 moves in a proximal direction (see arrow 61) relative to tool 43, thus fully capturing loop 29 (see Figures 20, 22, 24 showing captured loop) in the gap 49. Pulling both tools42 and 43 proximally will start to tension wire 26 as the tube 41 resists the collar 19. Filter body 14 will contact IVC contour and exert force on IVC contour as tension increases on 26 wire. When there is sufficiently high tension in the cable 26 to keep the apparatus 10 in place, there is no need to advance any more balls or stops 30-34 out of the collar anymore. In order to release the tension in cable member 26, tools 42 and 43 can be moved, i.e. pushed, distally. In order to release loop 29, one can slide tool 43 distally as the angle of recess 45 allows the cable 26 loop 29 to slide out of the recess 45. In this manner, loop 29 is automatically dislodged. At this point, tools 41, 42 and43 can be proximally withdrawn.

[0095] The present invention provides a better fit to the population range of IVC sizes and contours than current IVC filters with barbed tip ends and more contact area along the axis of each and every fiber compared to the current IVC filters. The present invention does not puncture the IVC vessel walls as it does not have barbed tips of the current IVC filters and has one proximal filter surface and one distal filter surface instead of one in current IVC filters. Over a long time, the vessel wall surfaces will scar and lock onto the fibers of the filter, preventing slippage of the IVC filter. Being flexible, the filter of the present invention is easier to retrieve than the current IVC filters after being placed for a very long time. These advantages make this filter apparatus safer for patients than the current IVC filters.

[0096] In order to install the filter apparatus 10, the filter body 14 is stretched out and assembled within the hollow tube 41 before the distal end of tube 41, tip 48. The wire loop 29 is ensnared by the keyhole configuration of the 2 rods 42, 43 (see Figures 17-19, 37-39). The 2 rods 42, 43 are lined up proximal to (below) the filter 10 in the hollow tube 40.

[0097] The distal tip end 48 of the tube 41 traverses the inferior vena cava 11 and reaches the infrarenal position.

[0098] The 2 rods 42, 43 are simultaneously pushed distally (above the tube 41) to expose the filter out of the tube 41 and out to the IVC [see Figure 10], When the lower collar 19 is out of the tube tip 48 (e.g., see figures 10, 11), the filter diameter is increased and the filter body 14 expanded towards the vessel wall 21 by pulling on the wire with the two rods 42, 43 simultaneously. The filter placement is adjusted by positioning the hollow tube 41 along the IVC, before the filter body 14 expands to the final size of the IVC [Figures 14-15], Still pulling the wire 35, the filter body 14 expands and exerts pressure on the IVC 11 where the weaved fibers 17 contact the vessel wall 21. The filter 10 is anchored in place and disturbances to the filter 10 cannot make the wire 35 overcome the protrusions 30, 31, 32, 33, 34 along its length. The wire loop 29 is pushed out of the keyhole cutout by sliding one rod and changing the alignment of the opposing cutouts [Figures 14 and 15],

[0099] Figures 27-30 illustrate the removal steps of the filter 10. The IVC filter 10 can be removed via Jugular access. A laparoscopic grasper 50 is inserted with an introducer sheath (not shown - such introducer sheaths are known and commercially available) from the jugular vein and tears off the end of the wire with protrusion 30, leaving untensioned bare wire 35 that releases the tension on the collars 18, 19, making the braided filter 10 lose its previous shape. As seen in Figure 29, the filter 10 is then pulled out through the jugular vein by a laparoscopic grasper 50 through the introducer sheath (not shown).

[0100] In another preferred embodiment, the upper collar and / or lower collar take on a different configuration from those seen in Figures 3-8. This collar configuration is shown in Figures 31-34. Figure 31 is a fragmentary side view of a preferred embodiment of the apparatus of the present invention showing lower collar 119. Figure 32 is a fragmentary cross-sectional view of lower collar 119. Collar 119 has a proximal end 128 and a distal end 129. Filter 14 attaches to the lower collar at the distal end 129. Arrow 120 shows direction of increasing tension of the ball cable 25. Lower collar 119 includes two main channels 121, 122 and a divider 123 with two openings 124, 125. Divider 123 separates the upper channel 121 from the lower channel 122. Preferably, divider 123 is angled / tilted so that larger opening 124 is closer to the proximal end 128 of the collar 119 than the smaller opening 125 is. Divider 123 comprises tilt or inclined surfaces 130, 131. The two openings share an open space which has a diameter at least large enough to allow cable member 26 to move from larger opening 124 to smaller opening 125. In the first opening 124, the openinghas a diameter which is larger than the diameter of the projections, balls, or stops 30-34, thus allowing the projections, balls, or stops to pass through. The second opening 125 has a diameter which is smaller than the diameter of the projections, balls, or stops, 30-34, thus preventing the projections, balls, or stops from passing through. Figure 33 is a fragmentary cross-sectional view of lower collar 119 with cable member 26 and stop 31 shown as well. Figure 34 shows how pulling the cable 26 (in direction 120) enables the balls, i.e. ball 31, to pass through the larger diameter of the divider, aided by tilt of the divider plane. That is, when the cable 26 is pulled proximally (see arrow 126), the ball 31 or stop or projection will slide down the tilt of the divider / keyhole 123 to the larger opening 124 where the ball can pass through and enter the lower channel 122. Once the ball 31 passes through the larger diameter hole 124 of the keyhole / divider, the cable 26 will pull in a distal direction (see arrow 127) (due to the memory of filter 14), causing the ball, stop or projection to slide up the tilt of the keyhole 123 and the narrow slot 125 now prevents the ball 31 from passing through and keeps the cable 26 in tension. The collar configuration can be used in place of collar 18 and collar 19, with orientation of outwardly opposing arrows. That is, if used as upper collar 18, the collar 119 would be inverted so that when the cable 26 is pulled away from the filter body 14, the ball, stop, or projection would slide towards the larger opening 124. When collar 119 is used in place of lower collar 19 or in place of lower collar 19 and upper column 18, neither the ball, stop, or projection or collar needs to be deformable. That is, the size of the openings 124, 125 can be fixed and non-deformable.

[0101] The collars and balls or stops can comprise yet a third configuration, as shown in Figures 40 and 41. Collar 219 is a ring-like structure which has a bore 240 extending from a first collar end 220 to a second collar end 221. Preferably, bore 240 is tapered so thatthe diameter of the opening at the first collar end 220 is greater than the diameter of the opening at the second collar end 221. The tapering of the bore 240 allows the stop or ball 234 to be pulled in down through the collar 219 while preventing the stop or ball 234 from moving back up through the collar 219 in the other direction. That is, the ball 234 can be pulled from one side of collar 219 (as seen in Figure 40) to the other side of collar 219 (as seen in Figure 41), but once the ball 234 is in the position seen in Figure 41, it cannot be pulled back through and regain the position seen in Figure 40. The shape of collar 219 and stop 234 allow the stop 234 to be pulled in one direction, but not the other. Stop 234 preferably comprises a spherical portion 236 and a flat portion 235. The spherical portion 236 is proximal the flat portion 235. In this way, cable member 226 can be pulled proximally (see arrow 232) and in doing so, spherical portion 236 of stop 234 causes collar 219 toexpand in a radial direction as the stop 234 passes from one end 220 to the other end 221 of the collar 219. Once stop 234 has reached the proximal side 221 of the collar, the flat portion 235 of the stop or ball 234, which has a diameter larger than the bore opening 240 at the proximal end 221, prevents the stop 234 from returning to its prior position (that of Figure 40). The collar 219 can be deformable in a radial direction, allowing the stop 235 to expand the diameter of the bore240 as the stop 234 moves from one end 220 to the other end 221, but not deformable in the axial direction, preventing the stop 234 from returning to the distal side of the collar 219.

[0102] Collar 219 can, but need not, have an open ring structure as seen in Figures 40 and 41. In the open ring structure version, collar 219 comprises a slit or opening or gap 243 in between ends241 and 242. A benefit of slit 243 is that slit 243 allows the collar 219 to more easily expand in a radial direction when ball or stop 234 is pulled in a proximal direction (see arrow 232). In the embodiments in which slit 243 is present, the diameter of the cable member 226 must be greater than the width of the slit 243 so as to ensure that the cable member 226 cannot separate from the collar 219 (by inadvertently moving in a radial direction).

[0103] In the non-open ring version (seen in Figure 42), collar 319 is similar to collar 219 except that it lacks a slit such as slit 243 in collar 219. In this way, the diameter of the cable member 326 is not necessarily impacted by the diameter of a slit in the collar as there is no such slit. Figure 43 shows a sectional view of stop 334 and collar 319. Stop 334 similar to stop 234 preferably has a spherical portion 336 and flat portion 335. The stop 334 can be pulled through the collar 319 by means of radial expansion of the collar 319. Similarly to the collar 219 of Figure 40 being pushed out radially, widening the opening or bore 240 so that stop 234 can traverse the collar 219, stop 334 can traverse the collar 319 by means of radial expansion of collar 319 as stop 334 passes through bore 340. Figure 43 shows a sectional view of collar 319. As seen in Figure 43, the diameter of the top or flat portion of stop 335 is larger than the bottom opening 344 of bore 340 so that the stop 334 can only traverse the collar 319 in one direction. Similar to the collar 219 of Figures 40-41, collar 319 is tapered so that the opening at the top 320 of the collar is larger than the opening at the bottom 321 of the collar. For an example of dimensions of the bore and stops, see Figures 42 and 43, wherein Cable 326 can have a diameter between 035 and 1.0 mm, for example; each stop 334 can have a diameter between 0.8 and 2.0 mm, for example; the first open ended bore, for example bore, the top of bore 340, can have a diameter between 1. And 1.6 mm; and the second open ended bore, for example, the bottom of bore 340 or bottom opening 344, can have a diameter between 0.4-1.4 mm, for example.

[0104] Ultimately, the top stop and collar and the bottom stop and collar do not need to be the same type of collar. The top collar should preferably be constructed so as to prevent the final ball or stop from passing through the collar, while the bottom collar should be configured in a way to allow the various stops or balls to pass through the collar in a proximal, but not distal direction, thus expanding the filter 14. For example, the top collar could have a stop with a flat end on the bottom which has a larger diameter than the bore of the top collar so that the stop is not able to be pulled through the top collar.

[0105] Figures 35 and 35 show an inferior vena cava 10 (shown without stops) which has a minimum dilation during inspiration (shown in Figure 35) and a maximum dilation during expiration (shown in Figure 35). As the inferior vena cava dilates or constricts, this braided filter 10 filter body 14, like an angioplasty balloon, with a longer body than it is wide, with a little flexibility caused by the braided form, will flex and adjust to the contours of the IVC. When the IVC constricts like in a Valsava episode, more of the braids surface area will press on the IVC walls 21, making the filter 10 more resistant to migration. When the IVC dilates (shown in Figure 36), the braid 14 readjusts to maintain contact with the shifted contour of the IVC. Preferably, the braided IVC filter 10 will be designed with a minimal axial length (longer body) to ensure IVC dilation will not cause a migration of the filter 10. As seen in Figures 35 and 35, the length from lower collar 19, 119 to upper collar 18, 119 does not change since the stops (not shown) prevent the filter body 14 from expanding length-wise. Accordingly, the filter body 14 folds (see Figure 35) and has more of the filter body 14 contact the vessel wall 21 when the IVC 11 is constricted.

[0106] Disturbances to the filter 10 include blood clots bumping into the filter or even spasms within the IVC.

[0107] Without limitation, the apparatus may further be characterized by one or more of the following statements:

[0108] Statement 1: A vena cava filter apparatus, comprising: a filter body having an upper end portion, lower end portion and a mesh, woven or braided wall; an upper collar connected to the filter body upper end portion, said upper collar having a first open ended bore; a lower collar connected to the filter body lower end portion, said lower collar having a second open ended bore; a cable member that extends between said collars and through each of said upper collar bore and lower collar bore; said cable member having a cable with a cable diameter and multiple spaced apart stops, each stop having a diameter that is larger than said cable diameter; each stop configured to pass through a collar bore; and each stop configured to engage a collar, whereinwhen one stop engages the upper collar and a second stop engages the lower collar, the collars can be moved closer together.

[0109] Statement 2: The vena cava apparatus of statement 1 wherein each stop is an enlarged element, such as an enlarged spherical element.

[0110] Statement 3: The vena cava apparatus of statement 1 or 2 wherein the upper collar and stops are deformable relative to each other.

[0111] Statement 4: The vena cava apparatus of one or more preceding statements, wherein the lower collar and stops are deformable relative to each other.

[0112] Statement 5: The vena cava apparatus of one or more preceding statements, wherein the second open ended bore has a conically shaped portion.

[0113] Statement 6: The vena cava apparatus of statements 1, 2, 3, or 4, wherein the second open ended bore has a frusto-conically shaped portion.

[0114] Statement 7: The vena cava apparatus of one or more preceding statements wherein the cable has a diameter of between 0.35 and 1.0 mm.

[0115] Statement 8: The vena cava apparatus of one or more preceding statements, wherein each stop has a diameter or thickness of between 0.8 and 2.0 mm.

[0116] Statement 9: The vena cava apparatus of one or more preceding statements, wherein the first open ended bore has a bore diameter of between 0.5 and 1.2 mm.

[0117] Statement 10: The vena cava apparatus of one or more preceding statements, wherein the second open ended bore has a bore diameter of between 1.0 and 1.6 mm.

[0118] Statement 11: A vena cava filter apparatus, comprising: a filter body having an upper end portion, lower end portion and a mesh, fabric or woven or braided wall surrounding an interior; an upper collar connected to the filter body upper end portion, said upper collar having a first open ended bore; a lower collar connected to the filter body lower end portion, said lower collar having a second open ended bore; a cable member that extends between said collars and through each of said upper collar bore and lower collar bore; said cable member having a cable with a cable diameter and multiple spaced apart stops, each stop having a diameter that is larger than said cable diameter; each stop configured to pass through a collar bore with a deformable connection; and each stop configured to engage a collar, wherein when one stop engages the upper collar and a second stop engages the lower collar, the collars can be moved closer together.

[0119] Statement 12: The vena cava apparatus of statement 11 wherein each stop is an enlarged rounded element.

[0120] Statement 13: The vena cava apparatus of statement 11 or 12 wherein the upper and lower collars are deformable.

[0121] Statement 14: The vena cava apparatus of one or more statements 11-13, wherein the stops are deformable when passing through a said collar.

[0122] Statement 15: The vena cava apparatus of one or more statements 11-14, wherein the second open ended bore is tapered.

[0123] Statement 16: The vena cava apparatus of one or more statements 11-15, wherein the second open ended bore has a tapered section.

[0124] Statement 17: The vena cava apparatus of one or more statements 11-16, wherein the cable has a diameter of between 0.35 and 1.0 mm.

[0125] Statement 18: The vena cava apparatus of one or more statements 11-17, wherein each stop has a diameter or thickness of between 0.8 and 2.0 mm.

[0126] Statement 19: The vena cava apparatus of one or more statements 11-18, wherein the first open ended bore has a bore diameter of between 0.5 and 1.2 mm.

[0127] Statement 20: A vena cava filter apparatus, comprising: a filter body having an upper end portion, lower end portion and a mesh, fabric or woven or braided wall; an upper collar connected to the filter body upper end portion, said upper collar having a first open ended bores; a lower collar connected to the filter body lower end portion, said lower collar having a second open ended bore; a wire that extends between the collars and through each collar bore; said wire having a wire diameter and multiple spaced apart stop members mounted to said wire, each stop member having a diameter larger than the wire diameter; each stop configured to pass through a collar bore; and each stop configured to engage a collar, wherein when one stop engages the upper collar and a second stop engages the lower collar, the collars can be moved closer together.

[0128] The following is a list of parts and materials suitable for use in the present invention:PARTS LISTPART NUMBER DESCRIPTION10 vascular filter apparatus11 inferior vena cavavein vein filter body / mesh filter body / fabric or braided or woven body upper end portion lower end portion tube / mesh wall / woven wall / fiber wall upper collar lower collar blood flow arrow vessel wall preliminary position / first position vessel lumen cable member upper end lower end loop projection / ball / stop projection / ball / stop projection / ball / stop projection / ball / stop projection / ball / stop wire / cable deployed position / installed position / second position upper collar internal bore lower collar internal bore gap / opening deployment tool assembly tool / tube tool / rod tool / rodcutout cutout arrow smallest diameter section tip gap retrieval tool arrow arrow arrow arrow arrow arrow catheter distal end proximal end collar arrow channel / bore channel / bore divider / keyhole opening / slot opening / slot arrow arrow proximal end distal end collar collar end collar end cable member arrowarrow projection / ball / stop flat portion spherical portion bore end end slit collar collar end collar end cable member projection / ball / stop flat portion spherical portion bore bottom opening

Claims

Claims1. A vena cava filter apparatus, comprising: a) a filter body having an upper end portion, lower end portion and a mesh, woven or braided wall; b) an upper collar connected to the filter body upper end portion, said upper collar having a first open ended bore; c) a lower collar connected to the filter body lower end portion, said lower collar having a second open ended bore; d) a cable member that extends between said collars and through each of said upper collar bore and lower collar bore; e) said cable member having a cable with a cable diameter and multiple spaced apart stops, each stop having a diameter that is larger than said cable diameter; f) each stop configured to pass through a collar bore; and g) each stop configured to engage a collar, wherein when one stop engages the upper collar and a second stop engages the lower collar, the collars can be moved closer together.

2. The vena cava apparatus of claim 1 wherein each stop is an enlarged spherical element.

3. The vena cava apparatus of claim 1 or 2 wherein the upper collar and stops are deformable relative to each other.

4. The vena cava apparatus of claim 1, 2, or 3 wherein the lower collar and stops are deformable relative to each other.

5. The vena cava apparatus of any one of claims 1-4 wherein the second open ended bore has a conically shaped portion.

5. The vena cava apparatus of any one of claims 1-4 wherein the second open ended bore has a frusto-conically shaped portion.

7. The vena cava apparatus of any one of claims 1-6 wherein the cable has a diameter of between 0.35 and 1.0 mm.

8. The vena cava apparatus of any one of claims 1-7 wherein each stop has a diameter or thickness of between 0.8 and 2.0 mm.

9. The vena cava apparatus of any one of claims 1-8 wherein the first open ended bore has a bore diameter of between 0.5 and 1.2 mm.

10. The vena cava apparatus of any one of claims 1-9 wherein the second open ended bore has a bore diameter of between 1.0 and 1.6 mm.

11. A vena cava filter apparatus, comprising: a) a filter body having an upper end portion, lower end portion and a mesh, fabric or woven or braided wall surrounding an interior; b) an upper collar connected to the filter body upper end portion, said upper collar having a first open ended bore; c) a lower collar connected to the filter body lower end portion, said lower collar having a second open ended bore; d) a cable member that extends between said collars and through each of said upper collar bore and lower collar bore; e) said cable member having a cable with a cable diameter and multiple spaced apart stops, each stop having a diameter that is larger than said cable diameter; f) each stop configured to pass through a collar bore with a deformable connection; and g) each stop configured to engage a collar, wherein when one stop engages the upper collar and a second stop engages the lower collar, the collars can be moved closer together.

12. The vena cava apparatus of claim 11 wherein each stop is an enlarged rounded element.

13. The vena cava apparatus of claim 11 or 12 wherein the upper and lower collars are deformable.

14. The vena cava apparatus of claim 11, 12, or 13 wherein the stops are deformable when passing through a said collar.

15. The vena cava apparatus of any one of claims 11-14 wherein the second open ended bore is tapered.

16. The vena cava apparatus of any one of claims 11-14 wherein the second open ended bore has a tapered section.

17. The vena cava apparatus of any one of claims 11-16 wherein the cable has a diameter of between 0.35 and 1.0 mm.

18. The vena cava apparatus of any one of claims 11-17 wherein each stop has a diameter or thickness of between 0.8 and 2.0 mm.

19. The vena cava apparatus of any one of claims claim 11-18 wherein the first open ended bore has a bore diameter of between 0.5 and 1.2 mm.

20. A vena cava filter apparatus, comprising:a) a filter body having an upper end portion, lower end portion and a mesh, fabric or woven or braided wall; b) an upper collar connected to the filter body upper end portion, said upper collar having a first open ended bores; c) a lower collar connected to the filter body lower end portion, said lower collar having a second open ended bore; d) a wire that extends between the collars and through each collar bore; e) said wire having a wire diameter and multiple spaced apart stop members mounted to said wire, each stop member having a diameter larger than the wire diameter; f) each stop configured to pass through a collar bore; and g) each stop configured to engage a collar, wherein when one stop engages the upper collar and a second stop engages the lower collar, the collars can be moved closer together.

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