FIELD OF THE INVENTIONThe present invention pertains to anchoring mechanisms for intravascular devices. More specifically, the present invention relates to anchoring mechanisms for releasably securing an intravascular device to an elongated member disposed within a blood vessel.[0001]
BACKGROUND OF THE INVENTIONMedical procedures to treat occlusive vascular diseases, such as angioplasty, atherectomy and stent deployment, routinely involve the insertion and subsequent removal of various intravascular devices. In an angioplasty procedure, for example, a physician will typically advance a guidewire having an attached embolic protection filter to a desired location within the body, and subsequently deploy a balloon catheter to dislodge embolic debris or thrombus from a lesion. In some instances, the physician may wish to deploy more than one device during the procedure. For example, if the first embolic protection filter becomes occluded with debris dislodged during the angioplasty procedure, the physician may wish to replace the occluded filter with a second filter.[0002]
One limitation with the prior art is the inability to deploy more than one device along a single guidewire without having to remove the guidewire from the patient's body. Although more recent developments in the art have focused on the use of multiple wires to rapidly deploy and exchange such devices, techniques employing a single guidewire typically require the physician to remove the guidewire from the body prior to the insertion of another device.[0003]
SUMMARY OF THE INVENTIONThe present invention pertains to anchoring mechanisms for intravascular devices. More specifically, the present invention relates to anchoring mechanisms for releasably securing an intravascular device to a guidewire disposed within the vasculature of a patient.[0004]
In one exemplary embodiment of the present invention, an anchoring mechanism for releasably securing an intravascular device to a guidewire comprises an embolic protection filter actuatable between an unlocked (i.e. disengaged) position and a locked (i.e. engaged) position. In the unlocked position, the anchoring mechanism is slidably and rotationally disposed along the guidewire, allowing the embolic protection filter to be advanced through the patient's vasculature. In the locked position, the anchoring mechanism is releasably secured to the guidewire, substantially preventing movement of the device along the guidewire. In certain implementations of the present invention, a placement device can be utilized to place the anchoring mechanism at a desired point along the guidewire. In other implementations, a retrieval mechanism can be utilized to disengage the anchoring mechanism from the guidewire.[0005]
BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a cross-sectional view of an anchoring mechanism in accordance with an embodiment of the present invention, wherein the anchoring mechanism includes a spring coil;[0006]
FIG. 2 is another cross-sectional view of the anchoring mechanism of FIG. 1, wherein the anchoring mechanism is releasable secured to the guidewire;[0007]
FIG. 3 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a split tube segment;[0008]
FIG. 4 is another cross-sectional view of the anchoring mechanism of FIG. 3, wherein the anchoring mechanism is releasably secured to the guidewire;[0009]
FIG. 5 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes one or more leaf clamps;[0010]
FIG. 6 is another cross-sectional view of the anchoring mechanism of FIG. 5, wherein the anchoring mechanism is releasably secured to the guidewire;[0011]
FIG. 7 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes one or more wires;[0012]
FIG. 8 is another cross-sectional view of the anchoring mechanism of FIG. 7, wherein the anchoring mechanism is releasably secured to the guidewire;[0013]
FIG. 9 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a spring;[0014]
FIG. 10 is another cross-sectional view of the anchoring mechanism of FIG. 9, wherein the anchoring mechanism is releasably secured to the guidewire;[0015]
FIG. 11 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a cam;[0016]
FIG. 12 is another cross-sectional view of the anchoring mechanism of FIG. 11, wherein the anchoring mechanism is releasably secured to the guidewire;[0017]
FIG. 13 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention employing a cam;[0018]
FIG. 14 is another cross-sectional view of the anchoring mechanism of FIG. 13, wherein the anchoring mechanism is releasably secured to the guidewire;[0019]
FIG. 15 is yet another cross-sectional view of the anchoring mechanism of FIG. 13, wherein a decoupling tube is utilized to disengage the anchoring mechanism from the guidewire;[0020]
FIG. 16 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes an elastomeric object;[0021]
FIG. 17 is another cross-sectional view of the anchoring mechanism of FIG. 16, wherein the anchoring mechanism releasably secured to the guidewire;[0022]
FIG. 18 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a shape-memory tube;[0023]
FIG. 19 is another cross-sectional view of the anchoring mechanism of FIG. 18, wherein the anchoring mechanism is releasably secured to the guidewire;[0024]
FIG. 20 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes an expandable balloon;[0025]
FIG. 21 is another cross-sectional view of the anchoring mechanism of FIG. 20, wherein the anchoring mechanism is releasably secured to the guidewire;[0026]
FIG. 22 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes an O-ring;[0027]
FIG. 23 is another cross-sectional view of the anchoring mechanism of FIG. 22, wherein the anchoring mechanism is releasably secured to the guidewire;[0028]
FIG. 24 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes one or more deflectable tabs;[0029]
FIG. 25 is another cross-sectional view of the anchoring mechanism of FIG. 24, wherein the anchoring mechanism is releasably secured to the guidewire;[0030]
FIG. 26 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a circular object;[0031]
FIG. 27 is another cross-sectional view of the anchoring mechanism of FIG. 26, wherein the anchoring mechanism is releasably secured to the guidewire;[0032]
FIG. 28 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a flared collet;[0033]
FIG. 29 is another cross-sectional view of the anchoring mechanism of FIG. 28, wherein the anchoring mechanism is releasably secured to the guidewire;[0034]
FIG. 30 is another cross-sectional view of the anchoring mechanism of FIG. 28, wherein the anchoring mechanism further includes threads;[0035]
FIG. 31 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes an offset block;[0036]
FIG. 32 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a split-jawed collet and a spring;[0037]
FIG. 33 is another cross-sectional view of the anchoring mechanism of FIG. 32, wherein a retrieval sheath is secured to the anchoring mechanism;[0038]
FIG. 34 is another cross-sectional view of the anchoring mechanism of FIG. 32, wherein a second sheath and decoupling tube are utilized to disengage the anchoring mechanism from the guidewire;[0039]
FIG. 35 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a sleeve;[0040]
FIG. 36 is another cross-sectional view of the anchoring mechanism of FIG. 35, wherein a retrieval sheath is secured to the anchoring mechanism;[0041]
FIG. 37 is another cross-sectional view of the anchoring mechanism of FIG. 35, wherein a second sheath and decoupling tube are utilizing to disengage the anchoring mechanism from the guidewire;[0042]
FIG. 38 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes one or more latches;[0043]
FIG. 39 is another cross-sectional view of the anchoring mechanism of FIG. 38, wherein a retrieval sheath is secured to the anchoring mechanism;[0044]
FIG. 40 is another cross-sectional view of the anchoring mechanism of FIG. 35, wherein a second sheath is advanced along the guidewire;[0045]
FIG. 41 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a wedge;[0046]
FIG. 42 is another cross-sectional view of the anchoring mechanism of FIG. 41, wherein the anchoring mechanism is releasably secured to the guidewire;[0047]
FIG. 43 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention employing a wedge;[0048]
FIG. 44 is another cross-sectional view of the anchoring mechanism of FIG. 43, wherein the object is advanced along the wedge in a second position;[0049]
FIG. 45 is yet another cross-sectional view of the anchoring mechanism of FIG. 43, wherein anchoring mechanism is releasably secured to the guidewire in a third position;[0050]
FIG. 46 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention employing a threaded wedge;[0051]
FIG. 47 is another cross-sectional view of the anchoring mechanism of FIG. 46, wherein the anchoring mechanism is releasably secured to the guidewire;[0052]
FIG. 48 is a perspective view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a slotted tube;[0053]
FIG. 49 is a cross-sectional view of the anchoring mechanism of FIG. 48 along line[0054]49-49;
FIG. 50 is another perspective view of the anchoring mechanism of FIG. 48, wherein the anchoring mechanism is shown slidably disposed along a guidewire after heat setting;[0055]
FIG. 51 is another perspective view of the anchoring mechanism of FIG. 48, wherein the anchoring mechanism is releasably secured to the guidewire;[0056]
FIG. 52 is a perspective view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a slotted tube having multiple necked-down regions;[0057]
FIG. 53 is a cross-sectional view of the anchoring mechanism of FIG. 52 along line[0058]53-53, showing the first necked-down portion;
FIG. 54 is a cross-sectional view of the anchoring mechanism of FIG. 52 along line[0059]54-54, showing the second necked-down portion;
FIG. 55 is another perspective view of the anchoring mechanism of FIG. 52, wherein the anchoring mechanism is slidably disposed along the guidewire;[0060]
FIG. 56 is another perspective view of the anchoring mechanism of FIG. 52, wherein the anchoring mechanism is releasably secured to the guidewire;[0061]
FIG. 57 is a cross-sectional view of an anchoring mechanism in accordance with another embodiment of the present invention, wherein the anchoring mechanism includes a slotted tube having a wall with varying section moduli;[0062]
FIG. 58 is another cross-sectional view of the anchoring mechanism of FIG. 57 along line[0063]58-58, wherein the anchoring mechanism is slidably disposed along the guidewire; and
FIG. 59 is another cross-sectional view of the anchoring mechanism of FIG. 57, wherein the anchoring mechanism is releasably secured to the guidewire.[0064]
DETAILED DESCRIPTION OF THE INVENTIONThe following description should be read with reference to the drawings wherein like reference numerals indicate like elements throughout the several views. The detailed description and drawings illustrate example embodiments of the claimed invention. The drawings, which are not necessarily to scale, depict several embodiments and are not intended to limit the scope of the invention. Although examples of construction, dimensions, materials and manufacturing processes are illustrated for the various elements, those skilled in the art will recognize that many of the examples provided have suitable alternatives that may be utilized.[0065]
FIG. 1 is a cross-sectional view illustrating an[0066]anchoring mechanism10 in accordance with an exemplary embodiment of the present invention. Anchoringmechanism10 comprises aspring coil12 slidably and rotationally disposable about aguidewire14 in an unlocked (i.e. disengaged) position, and releasably securable to theguidewire14 in a locked (i.e. engaged) position.
[0067]Spring coil12 comprises awire coil segment16 adapted to receiveguidewire14, adistal portion18, and aproximal portion20. Thedistal portion18 ofspring coil12 is attached to aproximal end22 of an intravascular device such as an embolic protection filter (not shown). Theproximal portion20 ofspring coil12 extends proximally in a U shape such that when unconstrained radially, theproximal portion20 ofspring coil12 expands radially, causing thewire coil segment16 to contract and frictionally engage theguidewire14.
In certain embodiments,[0068]spring coil12 may be formed as a separate component, and then attached to the intravascular deviceproximal end22 prior to insertion in the patient. Attachment of thespring coil12 to the intravascular deviceproximal end22 may be accomplished by any number of suitable attachment means, including soldering, welding, crimping and/or adhesive bonding. In other embodiments, thespring coil12 and intravascular device may be formed as a single member using, for example, a mold injection process.
[0069]Spring coil12 may be formed of any number of suitable materials biocompatible with the body. For example,spring coil12 may be formed of a metal such as303 or316 stainless steel. Alternatively, thespring coil12 may be formed of a polymeric material such as polypropylene (PP), polyvinyl chloride (PVC), polyethylene and/or polytetrafluoroethylene (PTFE). In one particular implementation,spring coil12 may comprise a shape-memory material such as nickel-titanium alloy (Nitinol).
A[0070]placement tube26 can be used to advance theanchoring mechanism10 to a desired location within a blood vessel, and to actuate thespring coil12 between the locked and unlocked positions.Placement tube26 has aninner lumen28 configured to disengagespring coil12 from theguidewire14 when disposed about theproximal portion20. As shown in FIG. 1,placement tube26 can be used to compress theproximal portion20 ofspring coil12 inwardly towards theguidewire14, causing thewire coil segment16 to expand slightly to permit thespring coil12 to slide and rotate about theguidewire14.
To engage the[0071]anchoring mechanism10 along theguidewire14,placement tube26 is withdrawn proximally until theproximal portion20 ofspring coil12 is unconstrained within theinner lumen28, as shown in FIG. 2. Once unconstrained by theplacement tube26, theproximal portion20 ofspring coil12 expands radially, causing thewire coil segment16 to compress about theguidewire14.
To release the[0072]anchoring mechanism10 from theguidewire14,placement tube26 can be advanced distally alongguidewire14 until theproximal portion20 is contained at least in part withininner lumen28. Continued advancement of theplacement tube26 distally compresses theproximal portion20, forcing thewire coil segment16 to expand outwardly and disengage from theguidewire14. Once disengaged from theguidewire14, theanchoring mechanism10 and attached intravascular device can then be withdrawn from the patient's body.
FIG. 3 illustrates an[0073]anchoring mechanism110 in accordance with another exemplary embodiment of the present invention.Anchoring mechanism110 comprises asplit tube segment112 having aproximal section134, adistal section136, and abend region138. Thedistal section136 ofsplit tube segment112 is biased to deflect inwardly to frictionally engage theguidewire14.
A[0074]placement tube126 can be utilized to advance thesplit tube segment112 along theguidewire14, and to actuate thedistal section136 between the unlocked and locked positions.Placement tube126 has a proximal portion (not shown) and adistal portion130. Thedistal portion130 ofplacement tube126 includes a reducedouter diameter portion132 having an outer diameter that is smaller than the inner diameter ofsplit tube segment112, allowing thesplit tube segment112 to slide thereon, thereby preventing thedistal section136 ofsplit tube segment112 from frictionally engaging theguidewire14.
To frictionally engage the[0075]anchoring mechanism110 about the guidewire,placement tube126 is retracted proximally along theguidewire14, permitting thedistal section136 of thesplit tube segment112 to deflect inwardly and compress against theguidewire14, as shown in FIG. 4. To disengage theanchoring mechanism110 from theguidewire14,placement tube126 can be advanced distally, forcing thedistal section136 ofsplit tube segment112 to disengage from theguidewire14.
In the exemplary embodiment illustrated in FIGS.[0076]3-4, splittube segment112 is configured to function as a proximal stop forembolic protection filter114, preventing movement of thefilter114 proximally thereof. As with any of the embodiments described herein, however, thesplit tube segment112 may be attached to, or form part of, anembolic protection filter114. In such cases, the anchoring mechanism may be utilized to releasably secure theembolic protection filter114 directly to theguidewire14.
In another exemplary embodiment illustrated in FIG. 5, an[0077]anchoring mechanism210 in accordance with the present invention may include one or more leaf clamps.Anchoring mechanism210 comprises atube segment212 having aproximal section234, adistal section236, and abend region238. Thedistal section236 oftube segment212 is biased to bend inwardly towards theguidewire14, forming one or more leaf clamps adapted to frictionally engage theguidewire14 in a locked position.
A[0078]placement tube226 can be utilized to advance thetube segment212 along theguidewire14, and to actuate thedistal section236 between the unlocked and locked positions.Placement tube226 has adistal section230 having an outer diameter that is smaller than the inner diameter of thetube segment212, allowing thedistal section230 ofplacement tube226 to slide withintube segment212. Whenplacement tube226 is inserted withintube segment212 distal thebend region238, thedistal section236 oftube segment212 is substantially prevented from engaging theguidewire14, as shown in FIG. 5.
To engage the[0079]anchoring mechanism210 along theguidewire14,placement tube226 is retracted proximally until thedistal section230 of theplacement tube226 isproximal bend region238, permitting thedistal section236 of thetube segment212 to deflect inwardly and compress against theguidewire14, as shown in FIG. 6. To subsequently release the lock,placement tube226 can be advanced distally, forcing thedistal section236 oftube segment112 to disengage from theguidewire14.
FIG. 7 illustrates an[0080]anchoring mechanism310 in accordance with another exemplary embodiment of the present invention.Anchoring mechanism310 comprises atubular member326 and one ormore wires312 adapted to frictionally engage theguidewire14 in a locked position.Tubular member326 has a proximal end (not shown) and adistal end330. Eachwire312 is attached at adistal end318 to theproximal end322 of an intravascular device (e.g. an embolic protection filter). Theproximal end320 eachwire312, in turn, is attached to thedistal end330 of thetubular member326.
To engage the[0081]anchoring mechanism310 along theguidewire14,tubular member326 is rotated in either a clockwise or counterclockwise direction until the one ormore wires312 frictionally engage theguidewire14, as shown in FIG. 8. If desired, an optional coating can be applied to thewires312 and/or theguidewire14 to increase the frictional force therebetween.
To subsequently release the[0082]anchoring mechanism310 from theguidewire14,placement tube326 can be rotated in an opposite direction until the one ormore wires312 disengage from theguidewire14. Once disengaged, theanchoring mechanism310 and intravascular device can then be removed from the patient's body.
In a similar embodiment illustrated in FIG. 9, an[0083]anchoring mechanism410 in accordance with an exemplary embodiment of the present invention may include atubular member426 and aspring412.Spring412 is formed of a flexible wire having adistal end418 and aproximal end420. Thedistal end418 ofspring412 is attached to theproximal portion422 of an embolic protection filter. Theproximal end420 ofspring412, in turn, is attached thedistal end430 oftubular member426.
In an unlocked position illustrated in FIG. 9,[0084]spring412 is adapted to slide and rotate aboutguidewire14, allowing the intravascular device to be advanced along theguidewire14 and placed at a desired location within the body. To engage thespring412 along theguidewire14,tubular member426 is withdrawn proximally, forcing thespring412 to stretch axially and compress radially about theguidewire14. As with the previous embodiment, an optional coating can be applied to increase the frictional force between theguidewire14 and thespring412.
In another exemplary embodiment illustrated in FIG. 11, an[0085]anchoring mechanism510 in accordance with the present invention may employ a cam.Anchoring mechanism510 comprises atube segment540 coupled to aproximal portion522 of an embolic protection filter (not shown).Tube segment540 includes an expandedportion542 defining aninner chamber544 having aninner wall surface546.
Disposed within[0086]inner chamber544 is anobject512 having adistal section518 and aproximal section520. The distal and/orproximal sections518,520 may each include a notch that permits the object ends518,520 to bend inwardly when compressed radially against theinner wall surface546 ofinner chamber544.
In a first (i.e. unlocked) position illustrated in FIG. 11, the[0087]object512 is positioned withinchamber544 such that neither theproximal end520 nor thedistal end518 ofobject512 is in contact with theinner wall surface546. In this position, theobject512 is slidably and rotationally disposed along theguidewire14, allowing the intravascular device to be placed within the patient's vasculature.
To engage the[0088]anchoring mechanism510 along theguidewire14, thetube segment540 and attached intravascular device can be moved along theguidewire14, forcing theobject512 disposed within thechamber544 to compress against theinner wall surface546. Continued advancement of thetube segment540 along theguidewire14 forces one of the notched ends (e.g. proximal end520) to bend inwardly and frictionally engage theguidewire14, as shown in FIG. 12.
Although the exemplary embodiment illustrated in FIGS.[0089]11-12 shows an object having a notch formed on or both ends, it is contemplated that other objects can be utilized without deviating from the scope of the invention. In certain embodiments, for example, the object may comprise a ball, wedge or coil. In other embodiments, the geometry of the inner wall surface may be .circular, rectangular or have an irregular shaped surface.
In one such variation illustrated in FIGS.[0090]13-15, ananchoring mechanism610 in accordance with an exemplary embodiment of the present invention comprises acircular object612 disposed within achamber644 having an irregularly shapedinner wall surface646. Theinner wall surface646 oftube segment642 includes one ormore recesses648 substantially conforming in size and shape to the dimensions of thecircular object612.
In an first (i.e. unlocked), the[0091]circular object612 is positioned within theinner chamber644 such that theobject612 is not in contact with either of therecesses648. To engage theanchoring mechanism610 along theguidewire14,tube segment640 is moved along theguidewire14 until thecircular object612 locks into one of therecesses648, as shown in FIG. 14.
To disengage the[0092]anchoring mechanism610 from theguidewire14, adecoupling tube650 can be advanced along theguidewire14 to disengage thecircular object612 from the recessedsurface648, as shown in FIG. 15. Thedistal end652 of the decoupling tube650 -may have a geometry corresponding in size and shape to the particular object employed. For example, thedistal end652 ofdecoupling tube650 may be curved slightly to correspond with the shape of thecircular object612.
FIG. 16 illustrates an[0093]anchoring mechanism710 in accordance with another exemplary embodiment of the present invention. Anelastomeric object712 is coupled to a reducedinner diameter portion722 disposed on theproximal end722 of an embolic protection filter (not shown). Theelastomeric object712 is attached at adistal end736 to the reducedinner diameter portion722 atnotch754, and at aproximal end734 to aplacement tube726. In use, theelastomeric object712 is configured to lock onto theguidewire14 when unconstrained by a tab disposed on thedistal end730 of theplacement tube726.
In a first (i.e. unlocked) position illustrated in FIG. 16,[0094]placement tube726 is configured to attach to aproximal end734 of theelastomeric object712, causing it to stretch axially and disengage from theguidewire14. To engage theanchoring mechanism710 along theguidewire14,placement tube726 is retracted proximally, causing theproximal end734 of theelastomeric object712 to detach from the tab on thedistal end730 of theplacement tube726. Once detached, theelastomeric object712 reverts to its natural, pre-stretched state, causing it to frictionally engage theguidewire14, as shown in FIG. 17.
FIG. 18 illustrates an[0095]anchoring mechanism810 in accordance with yet another exemplary embodiment of the present invention.Anchoring mechanism810 comprises ashape memory tube812 having a pre-defined shape which, when compressed radially by aplacement tube826, functions in an unlocked position, and when unconstrained radially, functions in a locked position. To bias theshape memory tube812 to radially expand and frictionally engage theguidewire14 in the locked position, a super elastic material such as a nickel titanium alloy (Nitinol) may be used.
In the exemplary embodiment illustrated in FIG. 18, the[0096]distal end818 ofshape memory tube812 further includes a joint856 adapted to permit rotation of theshape memory tube812 relative to theproximal end822 ofembolic protection filter814. In use, joint856 permits rotation of the embolic protection filter within the patient's body while substantially preventing movement of the intravascular device along theguidewire14.
A[0097]placement tube826 may be utilized to advance theshape memory tube812 andembolic protection filter814 along theguidewire14, and to actuate theshape memory tube812 between the unlocked and locked positions.Placement tube826 has a proximal end (not shown), adistal end830, and aninner lumen828. Theinner lumen828 is configured in size and shape to radially compress theshape memory tube812 therein, allowing theanchoring mechanism810 to slide and rotate about theguidewire14. To engage theanchoring mechanism810 along theguidewire14,placement tube826 can be withdrawn proximally, allowing theshape memory tube812 to revert to its pre-defined shape and frictionally engage theguidewire14, as shown in FIG. 19.
To disengage the[0098]anchoring mechanism810 from theguidewire14,placement tube826 is advanced distally until thedistal end830 is located proximate and proximal theproximal end820 ofshape memory tube812. Continued advancement of theplacement tube826 distally causes the shape-memory tube812 to radially compress withininner lumen828 and disengage from theguidewire14. Thedistal end830 ofshape memory tube812 may be flared slightly to facilitate advancement of theplacement tube826 about theshape memory tube812.
FIG. 20 illustrates an[0099]anchoring mechanism910 in accordance with yet another exemplary embodiment of the present invention.Anchoring mechanism910 comprises aproximal end portion922 of an embolic protection filter (not shown) containing anexpandable lumen958 having aninlet port960 and anexpandable balloon962. Apressure source926 in fluid communication with theinlet port960 is adapted to provide fluidic pressure to theexpandable balloon962 to actuate the device between the unlocked and locked positions.
As shown in FIG. 21, when fluidic pressure from[0100]pressure source926 is applied toinlet port960,balloon962 expands withinexpandable lumen958 forcing theinnermost portion964 of theexpandable lumen958 to deflect inwardly and engage theguidewire14. To disengage theanchoring mechanism910 from theguidewire14, fluid is evacuated from theballoon962, causing theinnermost portion962 of theexpandable lumen958 to disengage from theguidewire14.
FIG. 22 illustrates an[0101]anchoring mechanism1010 in accordance with yet another exemplary embodiment of the present invention.Anchoring mechanism1010 comprises aproximal portion1022 of an embolic protection filter (not shown) having adeflectable section1012 thereon actuatable between an unlocked (i.e. disengaged) position and a locked (i.e. engaged) position.
[0102]Deflectable section1012 has a relatively small outer diameter, allowing thedeflectable section1012 to deflect radially and compress along theguidewire14 when an elastomeric O-ring1062 is disposed thereon. One ormore notches1066 disposed at various locations along the inner diameter ofdeflectable section1012 may also be employed to engage thedeflectable section1012 along theguidewire14.
In a first position shown in FIG. 22,[0103]deflectable section1012 is disengaged from theguidewire14, allowing the intravascular device to slide and rotate about theguidewire14. To engage theanchoring mechanism1010 along theguidewire14, apush tube1068 is positioned proximate and proximal theproximal end1020 of the intravascular device. Holding the intravascular device stationary withpush tube1068, aplacement tube1026 having an inwardly facingtab1030 is withdrawn proximally, forcing the O-ring1062 to slide proximally to a second position about thedeflectable section1012, as shown in FIG. 23. The inward force exerted by the O-ring1062 forces thedeflectable section1012 to bend inwardly and compress against theguidewire14.
FIG. 24 illustrates an[0104]anchoring mechanism1110 in accordance with yet another exemplary embodiment of the present invention.Anchoring mechanism1110 comprises aplacement tube1126, apush tube1168 and a plurality ofradial tabs1112 extending from theproximal portion1122 of an embolic protection filter (not shown). The deflectableradial tabs1112 are biased inwardly such that when unconstrained bypush tube1168, theradial tabs1112 deflect inwardly towards theguidewire14.
[0105]Push tube1168 includes a tapereddistal end1170 having a size and shape that corresponds with the size and shape of the deflectableradial tabs1112. Theplacement tube1126 includes one or more inwardly facingtabs1130 that can be utilizing to transport theanchoring mechanism1110 along theguidewire14, and to subsequently release theanchoring mechanism1110 once engaged.
To engage the[0106]anchoring mechanism1110 along theguidewire14,push tube1168 is retracted proximally until the deflectableradial tabs1112 are unconstrained by the tapereddistal end1170 ofpush tube1168. Once unconstrained, theradial tabs1112 deflect inwardly and frictionally engage theguidewire14, as shown in FIG. 25. Once engaged, theplacement tube1126 can then be retracted proximally, causing the embolic protection filter to deploy within the patient's vessel.
To disengage the[0107]anchoring mechanism1110 from theguidewire14,placement tube1126 is advanced distally until the one ormore tabs1130 are positioned proximate and proximal acorresponding tab1172 located on the embolic protection filter. Continued advancement of theplacement tube1126 distally causes the one or more inwardly facingtabs1130 to bend slightly, allowing the one or moreradial tabs1130 to displace distal thecorresponding tab1172 located on the embolic protection filter. Thepush tube1168 can then be advanced distally, forcing the deflectableradial tabs1112 to disengage theanchoring mechanism1110 from theguidewire14.
FIG. 26 illustrates an[0108]anchoring mechanism1210 in accordance with yet another exemplary embodiment of the present invention.Anchoring mechanism1210 comprises acircular object1212, aplacement tube1226 having an opening1230 adapted to contain thecircular object1212, and tworecesses1274,1276 disposed on theproximal portion1222 of an embolic protection filter (not shown). Theanchoring mechanism1210 is slidably and rotationally disposed along theguidewire14 when thecircular object1212 is engaged within the first (i.e. larger)recess1274, and releasably secured to theguidewire14 when thecircular object1212 is engaged within the second (i.e. smaller)recess1276.
In a first position illustrated in FIG. 26, the[0109]circular object1212 is disposed within thefirst recess1274. Thefirst recess1274 is configured in size and shape to allow thecircular object1212 to rotate therein, allowing theanchoring mechanism1210 to be moved along theguidewire14. To engage theanchoring mechanism1210 along theguidewire14,placement tube1226 is withdrawn proximally until thecircular object1212 engages thesecond recess1276, as shown in FIG. 27. Thesecond recess1276 has a smaller inner diameter such that, when thecircular object1212 is retracted from thefirst recess1274 to thesecond recess1276, thecircular object1212 compresses against theguidewire14.
FIG. 28 illustrates an[0110]anchoring mechanism1310 in accordance with yet another exemplary embodiment of the present invention employing a flaredcollet1312. As shown in FIG. 28, the flaredcollet1312 includes a reduced inner diameterdistal portion1336 that permits thecollet1312 to deflect inwardly and frictionally engage theguidewire14 when compressed radially by aplacement tube1326.
To engage the[0111]collet1312 along theguidewire14,placement tube1326 is advanced distally, forcing thedistal portion1336 of thecollet1312 to bend inwardly and frictionally engage theguidewire14, as shown in FIG. 29. To disengage thecollet1312 from theguidewire14, theplacement tube1326 is retracted proximally until thedistal portion1336 disengages from theguidewire14.
In an alternative embodiment illustrated in FIG. 30, the inner diameter of[0112]placement tube1326 may include threads adapted to engage a corresponding set of threads disposed on the outer diameter of thecollet1312. To engage thecollet1312 along theguidewire14,placement tube1326 is rotated until the threads on theplacement tube1326 engage the threads on thecollet1312. Continued rotation of theplacement tube1326 relative to thecollet1312 causes thecollet1312 to frictionally engage theguidewire14 in a manner similar to that described with respect to FIG. 29.
FIG. 31 illustrates an[0113]anchoring mechanism1410 in accordance with another exemplary embodiment of the present invention utilizing an offset block.Clamping mechanism1410 comprises atubular member1412 having a plurality of radially offsettabs1478 extending inwardly towards theguidewire14. The offsettabs1478 are staggered at various locations along the inner diameter of thetubular member1412. In use, the radially offsettabs1478 prevent movement of theanchoring mechanism1410 along theguidewire14 in the absence of a force applied thereto by the operator.
FIG. 32 illustrates yet another exemplary embodiment of the present invention utilizing a split jawed collet operatively coupled to a spring seat. As shown in a locked position in FIG. 32,[0114]anchoring mechanism1510 comprises aproximal portion1522 of an embolic protection filter having aninner lumen1528 configured to receive theguidewire14.
Secured within the[0115]inner lumen1528 ofproximal portion1522 is aspring1512 that is frictionally engageable alongguidewire14 in a locked position, and slidably and rotationally disposed aboutguidewire14 in an unlocked position.Spring1512 may be formed from a laser cut tube comprised of a shape memory material such as Nitinol. Alternatively,spring1512 may be formed from a metal such as303 or316 stainless steel. In some embodiments,spring1512 may be formed from a highly radiopaque material (e.g. 316L stainless steel or platinum) to permit fluoroscopic monitoring of the device.
A split jawed[0116]collet1536 disposed about aspring seat1582 formed on theproximal portion1522 of the embolic protection filter may be used to actuate thespring1512 between the locked and unlocked positions. Split jawedcollet1536 can be formed from a split tubular member, similar to that shown with respect to FIGS.28-29. In a locked position illustrated in FIG. 32, the split jawedcollet1536 compresses betweenseveral notches1584 formed onseat1582, which biases thespring1512 axially, forcing thespring1512 to frictionally engage theguidewire14.
To disengage the[0117]spring1512 from theguidewire14, the operator advances aretrieval sheath1526 having one ormore retrieval fingers1530 distally until the one ormore retrieval fingers1530 lock onto a first enlargedouter diameter section1582 formed onproximal portion1522, as shown in FIG. 33. The one ormore retrieval fingers1530 are configured to bend in only a single direction, allowing theretrieval sheath1526 to lock onto theproximal portion1522 of the embolic protection filter. The one ormore retrieval fingers1530 may be formed from any number of suitable materials such as Nitinol, nylon, polyether-ether ketone (PEEK), etc.
Once the[0118]retrieval sheath1526 is engaged along theproximal portion1522 of the filter, the operator next advances asecond sheath1584 along the guidewire until a second set ofretrieval fingers1586 engage a second enlargedouter diameter section1588 formed onproximal portion1522. Once the second set ofretrieval fingers1586 engage the second enlargedouter diameter section1588, apush tube1568 is advanced distally, forcing thesplit jaw collet1536 to compress axially, causing thespring1512 to frictionally disengage from the guidewire, as shown in FIG. 34. The embolic protection filter can then be retracted alongguidewire14 and removed from the patient's body, if desired.
FIG. 35 illustrates an[0119]anchoring mechanism1610 in accordance with yet another exemplary embodiment of the present invention utilizing asleeve1612.Anchoring mechanism1610 comprises aproximal portion1622 of an embolic protection filter (not shown) having aninner lumen1628 configured to receive theguidewire14.
A[0120]spring1662 attached to theproximal portion1622 can be utilized to frictionally engage thesleeve1612 along theguidewire14.Spring1662 has aproximal end1634 and adistal end1636. Theproximal end1634 ofspring1662 is attached to atubular member1690 slidably disposed alongguidewire14. Thedistal end1636 ofspring1662 is fixedly attached to theproximal portion1622 of the embolic protection filter.
[0121]Sleeve1612 may be formed from a loosely braided material such as Dacron, and is configured to radially collapse when placed under tension by thespring1662. Thesleeve1612 is secured at adistal end1618 to theproximal portion1622 of the filter. Theproximal end1620 of the sleeve, in turn, is attached to thetubular member1690. In a locked position illustrated in FIG. 35, thespring1662 forces thesleeve1612 into tension axially, forcing thesleeve1612 to radially compress and frictionally engage theguidewire14.
To disengage the[0122]sleeve1612 from theguidewire14, the operator advances aretrieval sheath1626 having one ormore retrieval fingers1630 distally along theguidewire14 until the one ormore retrieval fingers1630 lock onto afirst notch1682 located on theproximal portion1622, as shown in FIG. 36. Once theretrieval sheath1626 is engaged along theproximal portion1622 of the filter, the operator next advances asecond sheath1684 along theguidewire14 until a second set ofretrieval fingers1686 engage asecond notch1688 form on the outer diameter ofproximal portion1622 proximal thefirst notch1682. Once the second set ofretrieval fingers1686 engage thesecond notch1688, apush tube1668 is advanced along theguidewire14, forcing thespring1662 into compression, and causing thesleeve1612 to radially expand and disengage from theguidewire14, as shown in FIG. 37.
FIG. 38 illustrates an[0123]anchoring mechanism1710 in accordance with yet another exemplary embodiment of the present invention.Anchoring mechanism1710 comprises atubular member1712 slidably and rotationally disposed aguidewire14, alocking tube1726, and afilter mount1722.Tubular member1712 has aproximal end1734, adistal end1736, and aninner lumen1728 configured to receive theguidewire14. Thefilter mount1722, which forms the proximal portion of an embolic protection filter (not shown), is slidably and rotationally disposed about thetubular member1712. Thedistal end1736 oftubular member1712 is flared slightly such that, in use, thefilter mount1722 is prevented from sliding off thedistal end1736 of thetubular member1722. If desired, thefilter mount1722 may be formed of a radiopaque material such as stainless steel, gold or platinum to enable the operator to fluoroscopically judge the location of the device within the patient's body.
[0124]Tubular member1712 further includes one ormore latches1792 adapted to frictionally engage theguidewire14 when actuated. Thelatches1792 may be formed by cutting thetubular member1712 at various locations along its length and/or radius. Theproximal end1720 of eachlatch1792 is attached to thetubular member1712, and acts as a pivot to permit thelatches1792 to bend inwardly towards theguidewire14. Thedistal end1718 of eachlatch1792, in turn, is bent at an angle of approximately 90°, forming a contact surface to frictionally engage theguidewire14. A slight upward deflection is heat set into eachlatch1792 to permit thetubular member1712 to slide along theguidewire14 when unconstrained radially.
A[0125]locking tube1726 may be utilized to frictionally engage the one ormore latches1792 along theguidewire14. Lockingtube1726 has an inner diameter slightly larger than the outer diameter oftubular member1712, allowing thetube1726 to slide over thetubular member1712 to engage the one ormore latches1792.
To frictionally engage the[0126]guidewire14, the lockingtube1726 is advanced distally along theguidewire14 to a location proximate and proximal theproximal end1734 oftubular member1712. Continued advancement of thelocking tube1726 distally forces thelatches1792 to rotate inwardly and frictionally engage theguidewire14, as shown in FIG. 39.
To subsequently disengage the[0127]latches1792 from theguidewire14, a retrieval system similar to that described with respect to FIGS.35-37 may be employed. For example, as shown in FIG. 39, aretrieval sheath1726 having one ormore retrieval fingers1730 may be advanced along theguidewire14 and secured to thefilter mount1722 at afirst notch1782. Once engaged, asecond sheath1784 having a second set ofretrieval fingers1786 may be advanced along theguidewire14 and locked onto asecond notch1788 formed on thelocking tube1726, as shown in FIG. 40. Thesecond sheath1784 can be retracted proximally until the one ormore latches1792 are unconstrained radially, allowing thetubular member1712 to slide and rotate along theguidewire14. The operator can then retract thesecond sheath1784 proximally, causing the one ormore latches1792 to disengage from theguidewire14.
FIG. 41 illustrates an[0128]anchoring mechanism1810 in accordance with yet another exemplary embodiment of the present invention utilizing a wedge.Anchoring mechanism1810 comprises anobject1812 that is slidably and rotationally disposed about aguidewire14 in an unlocked position, and releasably secured to theguidewire14 in a locked position.Object1812 has aproximal section1820 and adistal section1818. Theproximal section1820 ofobject1712 is configured to bend or flex inwardly towards theguidewire14 when compressed radially by awedge1894.
In the exemplary embodiment illustrated in FIG. 41,[0129]object1812 tapers distally, having a smaller outer diameter onproximal section1820 than on thedistal section1818. One ormore notches1882 disposed within the outer surface of theobject1812 further permit theproximal section1820 to bend or flex inwardly whenwedge1894 is advanced thereon.
The[0130]distal section1818 ofobject1812 may further optionally include a joint1856 adapted to permit rotation of theobject1812 relative to theproximal portion1822 of theembolic protection filter1814. In use, joint1856 permits rotation of theembolic protection filter1814 within the vessel while substantially preventing movement of theanchoring mechanism1810 along theguidewire14.
To frictionally engage the[0131]object1812 along theguidewire14, apush tube1868 can be advanced distally, forcing thewedge1894 to slide along theobject1812. Asheath1826 having a force-calibratedtab1830 adapted to bend in only one direction in response to a sufficient force exerted thereon can be utilized to hold theobject1812 in place when advancing thewedge1894. Continued movement of thewedge1894 relative to theobject1812 causes theobject1812 to compress radially, forcing theproximal section1820 to bend inwardly and frictionally engage theguidewire14. Once engaged, theretrieval sheath1826 can be withdrawn proximally until the force-calibratedtab1830 bends and compresses against thewedge1894, and until theembolic protection filter1814 is deployed within the vessel, as shown in FIG. 42. Thepush tube1868 can then be withdrawn proximally from the body, if desired.
In an alternative embodiment illustrated in FIGS.[0132]43-45, ananchoring mechanism1910 in accordance with the present invention may include anobject1912 that tapers proximally. As shown in FIG. 43,object1912 has a larger outer diameter on theproximal section1920 than on thedistal section1918. Theproximal section1920 is configured to bend or flex inwardly towards theguidewire14 when compressed radially by awedge1994. One ormore notches1982 disposed within the outer surface of theobject1912 further permit theproximal section1920 to bend or flex inwardly whenwedge1994 is advanced thereon.
In a first (unlocked) position illustrated in FIG. 43,[0133]object1912 is slidably and rotationally disposed about theguidewire14. To frictionally engage theobject1912 along theguidewire14, apush tube1968 is advanced distally against theobject1912, forcing theobject1912 to slide relative to thewedge1994, as shown in FIG. 44. Asheath1926 having a force-calibratedtab1930 adapted to bend in only one direction in response to a sufficient force exerted thereon can be utilized to hold thewedge1994 stationary when advancing theobject1912 via thepush tube1968. Continued advancement of thepush tube1968 distally, or in the alternative, retraction of theretrieval sheath1926 proximally, causes the force-calibratedtab1930 to bend and compress against thewedge1994, as shown in FIG. 45.
In an alternative embodiment illustrated in FIGS.[0134]46-47, ananchoring mechanism2010 in accordance with the present invention may include apush tube2068 having threads configured to engage a corresponding set of threads disposed on thewedge2094.Anchoring mechanism2010 comprises anobject2012 having aproximal section2020 and adistal section2018, aretrieval sheath2026, awedge2094, and apush tube2068. Theobject2012 tapers proximally, and forms the proximal portion of anembolic protection filter2014. Theproximal section2020 ofobject2012 is configured to bend or flex inwardly towards theguidewire14 when compressed radially by thewedge2094.
In the exemplary embodiment illustrated in FIGS.[0135]46-47,wedge2094 includes threads on its outer diameter configured to mate with a corresponding set of threads disposed on a reduced inner diameterdistal portion2070 of thepush tube2068.
To frictionally engage the[0136]object2012 along theguidewire14,push tube2068 is retracted proximally, forcing theproximal section2020 of theobject2012 to bend inwardly and frictionally engage theguidewire14. Once engaged, theretrieval sheath2026 may be withdrawn proximally, causing the force-calibratedtab2030 to bend and compress against thewedge2094, as shown in FIG. 47.
FIG. 48 illustrates an[0137]anchoring mechanism2110 in accordance with yet another exemplary embodiment of the present invention utilizing a slotted tube. As shown in FIG. 48,anchoring mechanism2110 comprises a slottedtube2112 having aninner lumen2114 configured to slidably receive a guidewire (not shown). As with any of the previous embodiments, the slottedtube2112 may form the proximal portion of an embolic protection filter, or may act as a proximal stop to prevent proximal movement of the filter along the guidewire.
In the exemplary embodiment illustrated in FIG. 48, slotted[0138]tube2112 comprises a thin-wall tube formed from a shape-memory material such as Nitinol. Slottedtube2112 includes a necked-down portion2116 having an inner diameter that is slightly smaller than the outer diameter of the guidewire.Several slots2118 located within the necked-down portion2116 are configured to expand slightly to allow the guidewire to slide withinlumen2114 when the slottedtube2112 is unconstrained radially. As can be seen in greater detail in FIG. 49, theslots2118 are circumferentially disposed 120° apart from each other, and extend through the wall of the slottedtube2112.
To expand the[0139]slots2116 in an outward direction, the slottedtube2112 can be heat treated at an appropriate temperature using, for example, a heater or a laser. Once heated, theslots2118 deform slightly, allowing theguidewire14 to be inserted through the slottedtube2112, as shown in FIG. 50. To facilitate heat setting of theslots2116, a shape memory material such as Nitinol can be used. In an alternative implementation, theslots2118 can be formed using an annealed steel or polymeric material. For example, theslots2116 can be molded to a particular dimension using a polymeric material such as polytetraflouroethylene, polyvinylchloride or ABS plastic.
To engage the[0140]anchoring mechanism2110 along theguidewire14, alocking tube2120 is advanced along theguidewire14 to a point proximate and proximal the necked-down portion2116 of slottedtube2112. The lockingtube2120 has an inner diameter that is slightly larger than the outer diameter of the slottedtube2112, allowing thelocking tube2120 to be advanced over the slottedtube2112. To releasably secure the slottedtube2112 to theguidewire14, the operator continues to advance thelocking tube2120 distally until the necked-down portion2116 compresses against theguidewire14, as shown in FIG. 51.
In an alternative embodiment illustrated in FIGS.[0141]52-56, the slotted tube may include several necked down regions located along its length configured to releasably secure to theguidewire14. As shown in FIG. 52,anchoring mechanism2210 comprises a slotted tube having a first necked-down region2216, and a second necked-down region2220 located distal the first necked-down region2216. The first necked-down region2216 includes twoslots2224 circumferentially disposed 180° apart from each other, and that extend through the wall of the slottedtube2212, as shown in FIG. 53. The second necked-down region2222, in turn, includes twoslots2226 that are radially offset 90° from theslots2224 on the first necked-down region2216, as shown in FIG. 54.
To engage the[0142]anchoring mechanism2210 along theguidewire14, alocking tube2220 similar to that discussed with respect to FIG. 51 is advanced along theguidewire14 to a point proximate and proximal to the first necked-down portion2216 of slottedtube2212, as shown in FIG. 56. Continued advancement of thelocking tube2220 about the first necked-down portion2216 compresses the slottedtube2212 against theguidewire14, as shown in FIG. 51. Further advancement of thelocking tube2220 distally causes the second necked-down portion2222 to compress against theguidewire14 in a similar manner.
Although the exemplary embodiment illustrated in FIGS.[0143]52-56 illustrates two lockingportions2216,2222 along the length of the slottedtube2212, it is to be understood that other configurations are possible without deviating from the scope of the invention. For example, a slotted tube having three or more necked-down regions can be employed. Moreover, the number of slots (e.g. 4, 5, 6, etc.) disposed within each necked-down region can be increased, if desired, to provide a greater number of locations for the slotted tube to frictionally engage the guidewire.
To further increase the frictional force exerted on the guidewire, the inner diameter of the slotted tube may include a roughened surface. The roughened surface may be formed by welding several small beads to the inner surface, sand blasting the inner surface, or by machining small grooves into the inner surface of the slotted tube. The slotted tube may also be formed from a material having a relatively porous surface, thereby increasing the roughness of the surface.[0144]
In another alternative embodiment illustrated in FIGS.[0145]57-59, ananchoring mechanism2310 in accordance with the present invention may include a slottedtube2312 comprising one ormore portions2328 having a relatively large section modulus, and one ormore portions2330 having a relatively small section modulus. As shown in a pre-heat treated position in FIG. 57, the slottedtube2312 may include several circumferentially disposedslots2332 extending through the wall of the slottedtube2312. The one ormore portions2328 having a relatively large section modulus are configured to distribute the axial force applied to the slotted tube when the embolic protection filter is moved along theguidewire14. In use, theslots2332 formed about the slottedtube2312 are configured to expand slightly to allow theguidewire14 to slide and rotate within the slottedtube2312 when unconstrained radially.
As can be seen in FIG. 58, the[0146]slots2332 may be formed in a direction substantially parallel to centerline of the slotted tube. Theslots2332 may be heat treated as discussed with respect to the previous embodiment, or may be formed during manufacture. Although theslots2332 illustrated in FIG. 58 are disposed along a line substantially parallel to the centerline of the slottedtube2312, other configurations are possible. In one embodiment, for example, the one or more slots may be helically disposed about the slottedtube2312.
To engage the[0147]anchoring mechanism2310 along theguidewire14, alocking tube2320 can be advanced along theguidewire14 to a point proximate and proximal to the necked-down portion2316 of slottedtube2312. Continued advancement of thelocking tube2312 distally about the necked-down portion2316 compresses the slottedtube2312 against theguidewire14, as shown in FIG. 59.Several protrusions2334 disposed on the outer diameter of the slottedtube2312 are configured to frictionally engage thelocking tube2320 against the slottedtube2312.
Having thus described the several embodiments of the present invention, those of skill in the art will readily appreciate that other embodiments may be made and used which fall within the scope of the claims attached hereto. Numerous advantages of the invention covered by this document have been set forth in the foregoing description. Changes may be made in details, particular in matters of shape, size and arrangement of parts without exceeding the scope of the invention. For example, while several of the embodiments illustrated herein illustrate the attachment of an embolic protection filter to the guidewire, it is to be understood that other intravascular devices may employ the anchoring mechanisms discussed herein. It will be understood that this disclosure is, in many respects, only illustrative.[0148]