Abstract:
Methods and devices for delivering and/or retrieving a filter fixed to a guidewire disposed within a blood vessel are disclosed. A system in accordance with the present invention comprises, an outer shaft having a proximal end, distal end and a wall defining an outer shaft lumen. The system also includes a stop mechanism disposed within the outer shaft lumen. The stop mechanism is preferably configured such that relative axial movement between the guidewire and the outer shaft may be selectively precluded.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates generally to devices and methods for treating occluded or stenoic blood vessels. More particularly, the present invention relates to devices and methods for providing temporary placement of a filter in a blood vessel during a procedure to remove an occlusion or stenosis.  
       BACKGROUND OF THE INVENTION  
       [0002]     Angioplasty, atherectomy and stent placement, among other procedures, have become well accepted for treatment of coronary lesions. These procedures are often performed as an alternative to coronary bypass. It is also possible, however, that a saphenous vein graft, which is used to bypass coronary lesions, may itself develop a lesion. These lesions may also be treated by minimally invasive procedures such as angioplasty, atherectomy and/or stent placement.  
         [0003]     When lesions are treated by these minimally invasive, percutaneous methods, it is possible that particles of plaque, thrombus or other material may break loose from the lesion and drift distally into the smaller coronary arteries. When these minimally invasive methods are performed on native arteries, the plaque or thrombus released during the procedure rarely causes embolization. When these procedures are performed on saphenous vein grafts, however, the incidence of embolism due to the breaking off of plaque or thrombus from the vein graft is substantially greater than from native arteries.  
         [0004]     The increased incidence of embolization is believed to be due, at least in part, to the larger diameter of the bypass graft relative to the native artery. The larger diameter of the graft results in a slower blood flow velocity through the graft than the native artery. In addition, the plaque and thrombus of vein grafts is somewhat more fragile than that found in native arteries.  
         [0005]     As the difference in embolism associated with treatment of native arteries and vein grafts has been noted, it would be desirable to develop techniques to reduce embolism associated with treatment of vein graft lesions. Additionally, where stent placement or other minimally invasive treatments are performed on the carotid artery, it would be desirable to limit the drift of plaque and thrombus toward the brain.  
       SUMMARY OF THE INVENTION  
       [0006]     The present invention relates generally to devices and methods for treating occluded or stenoic blood vessels. More particularly, the present invention relates to devices and methods for providing temporary placement of a filter in a blood vessel during a procedure to remove an occlusion or stenosis. A system in accordance with the present invention features an outer shaft having a proximal end, a distal end and a wall defining an outer shaft lumen. The system also includes a stop mechanism disposed within the outer shaft lumen. The stop mechanism is preferably configured such that relative axial movement between the guidewire and the outer shaft may be selectively precluded.  
         [0007]     In certain implementations of the invention, a proximal guidewire port extends through the wall of the outer shaft for allowing the guidewire to pass through the wall so that it is partially disposed within the shaft lumen. In an advantageous embodiment, the stop mechanism is disposed distally of the proximal guidewire port.  
         [0008]     In one aspect of the invention, the stop mechanism is adapted to mechanically engage the guidewire. In an additional aspect of the invention, the stop mechanism is adapted to frictionally engage the guidewire. In yet another aspect of the invention, the stop mechanism is adapted to apply a compressive force to the guidewire.  
         [0009]     The stop mechanism may feature a stop member. In certain implementations, the stop member features a ring, and the stop mechanism includes a stop fixed to the guidewire. In one embodiment, the stop member defines an aperture having a inner radial extent, and the stop has an outer radial extent. In an advantageous embodiment, the stop member defines an aperture having a inner radial extent, and the stop has an outer radial extent that is generally greater than the inner radial extent of the aperture defined by the stop member.  
         [0010]     In certain implementations of the invention, the stop member features a distal mating surface and the stop features a proximal mating surface. In an advantageous embodiment, the stop and the stop member are configured such that the proximal mating surface of the stop seats against the distal mating surface of the stop member.  
         [0011]     In certain implementations, the system features an inner shaft slidingly disposed within the outer shaft lumen. A gripper may be operatively coupled between the inner shaft and the outer shaft. Preferably, the gripper is configured such that relative axial movement between the inner shaft and the outer shaft causes the gripper to grasp the guidewire. In certain implementations, the gripper features a collet.  
         [0012]     In certain implementations, the gripper is fixed to the outer shaft. In other implementations, the gripper is fixed to the inner shaft. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1  is a partial cross-sectional view of a filter manipulating system in accordance with an exemplary embodiment of the present invention;  
         [0014]      FIG. 2  is an enlarged cross-sectional view of a portion of filter manipulating system of  FIG. 1 ;  
         [0015]      FIG. 3  is an additional enlarged cross-sectional view of the portion of filter manipulating system shown in  FIG. 2 ;  
         [0016]      FIG. 4  is an additional partial cross-sectional view of the filter manipulating system of  FIG. 1 ;  
         [0017]      FIG. 5  is a partial cross-sectional view of a filter manipulating system in accordance with an additional exemplary embodiment of the present invention;  
         [0018]      FIG. 6  is an additional partial cross-sectional view of the filter manipulating system of  FIG. 5 ;  
         [0019]      FIG. 7  is a partial cross-sectional view of a filter manipulating system in accordance with an exemplary embodiment of the present invention;  
         [0020]      FIG. 8  is an enlarged cross-sectional view of a portion of filter manipulating system of  FIG. 7 ;  
         [0021]      FIG. 9  is an additional enlarged cross-sectional view of the portion of filter manipulating system shown in  FIG. 8 ;  
         [0022]      FIG. 10  is an additional partial cross-sectional view of the filter manipulating system of  FIG. 7 ;  
         [0023]      FIG. 11  is a partial cross-sectional view of a filter manipulating system in accordance with an additional exemplary embodiment of the present invention;  
         [0024]      FIG. 12  is an additional partial cross-sectional view of the filter manipulating system of  FIG. 11 ;  
         [0025]      FIG. 13  is a partial cross-sectional view of a filter manipulating system in accordance with an additional exemplary embodiment of the present invention; and  
         [0026]      FIG. 14  is an additional partial cross-sectional view of the filter manipulating system of  FIG. 13 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0027]     The following detailed description should be read with reference to the drawings, in which like elements in different drawings are numbered in like fashion. The drawings which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. In some cases, the drawings may be highly diagrammatic in nature. Examples of constructions, materials, dimensions, and manufacturing processes are provided for various elements. Those skilled in the art will recognize that many of the examples provided have suitable alternatives that may be utilized.  
         [0028]      FIG. 1  is a partial cross-sectional view of a filter manipulating system  100  in accordance with an exemplary embodiment of the present invention. Filter manipulating system  100  includes a catheter  102  having an outer shaft  104  defining an outer shaft lumen  106  and an inner shaft  108  that is slidingly disposed within outer shaft lumen  106 .  
         [0029]     Outer shaft  104  includes a proximal end  158  and a distal end  160 . Outer shaft  104  includes a proximal portion  120 , a distal portion  122 , and a longitudinally collapsible portion  124  disposed between proximal portion  120  and distal portion  122 . In the embodiment of  FIG. 1 a  filter  126  of filter manipulating system  100  is disposed within a portion of outer shaft lumen  106  defined by distal portion  122  of outer shaft  104 . In the embodiment of  FIG. 1 , filter  126  is in a contracted configuration.  
         [0030]     Filter manipulating system  100  may preferably be used to deploy filter  126  within a blood vessel  128 . Filter manipulating system  100  may also preferably be used to retrieve a filter that is disposed within a blood vessel. In a preferred embodiment, filter  126  assumes an expanded configuration when it is disposed within blood vessel  128  and assumes a contracted configuration when it is disposed within outer shaft lumen  106  of catheter  102 .  
         [0031]     Filter manipulating system  100  of  FIG. 1  includes a guidewire  130  having a distal end that is fixed to filter  126 . In the embodiment of  FIG. 1 , guidewire  130  extends through an inner shaft lumen  132  defined by inner shaft  108 . Filter manipulating system  100  also includes a stop mechanism  134  for selectively limiting the longitudinal movement of guidewire  130  relative to proximal portion  120  of outer shaft  104 .  
         [0032]     In the embodiment of  FIG. 1 , stop mechanism  134  includes a gripper  136  that is preferably adapted to selectively grasp guidewire  130 . In the embodiment of  FIG. 1 , gripper  136  comprises a collet  138 . It is to be appreciated that gripper  136  may comprise various gripping elements without deviating from the spirit and scope of the present invention. Examples of gripping elements that may be suitable in some applications include a set of opposing jaws and a resilient bushing.  
         [0033]      FIG. 2  is an enlarged cross-sectional view of a portion of filter manipulating system  100  of  FIG. 1 . In  FIG. 2 , collet  138  is shown having an at rest shape. Collet  138  preferably also has a contracted shape in which collet  138  grasps guidewire  130 .  
         [0034]     In  FIG. 2  it may be appreciated that collet  138  includes a plurality of jaws  140 , each having a tapered portion  142  and a hinge portion  144 . Inner shaft  108  includes a mating taper  146 . In a preferred embodiment, relative movement between inner shaft  108  and proximal portion  120  of outer shaft  104  may be used to selectively urge jaws  140  of collet  138  against guidewire  130 . In the embodiment of  FIG. 2 , urging inner shaft  108  distally relative to proximal portion  120  of outer shaft  104  will preferably cause jaws  140  of collet  138  to grasp guidewire  130 .  
         [0035]      FIG. 3  is an additional enlarged cross-sectional view of the portion of filter manipulating system  100  shown in  FIG. 2 . In the embodiment of  FIG. 3  inner shaft  108  has been moved distally relative to outer shaft  104  and jaws  140  of collet  138  have been urged against guidewire  130 . In the embodiment of  FIG. 3 , collet  138  has been urged into a contracted shape.  
         [0036]     In  FIG. 3  it may also be appreciated that gripper  136  defines a hole  148 . An articulating rod  150  is shown extending through hole  148 . Articulating rod  150  may preferably be used to selectively collapse and expand longitudinally collapsible portion  124  of outer shaft  104 .  
         [0037]     Referring again to  FIG. 1 , it may be appreciated that a distal end of articulating rod  150  is fixed to a ring  152 . Ring  152  is preferably fixed to distal portion  122  of outer shaft  104  distally of longitudinally collapsible portion  124 . The proximal end of articulating rod  150  is fixed to a slider  154 . Slider  154  is disposed in sliding engagement with a hub  156  that is disposed about a proximal end  158  of outer shaft  104 . In a preferred embodiment, slider  154  and articulating rod  150  may be used to selectively collapse and expand longitudinally collapsible portion  124  of outer shaft  104 .  
         [0038]      FIG. 4  is an additional partial cross-sectional view of the filter manipulating system  100  of  FIG. 1 . In the embodiment of  FIG. 4 , longitudinally collapsible portion  124  of outer shaft  104  has been collapsed by urging slider  154  proximally relative to hub  156 . In the embodiment of  FIG. 4 , distal end  160  of outer shaft  104  is located proximally of filter  126  and filter  126  is disposed outside of outer shaft lumen  106 . In  FIG. 4  it may be appreciated that filter  126  is free to assume an expanded configuration when it is outside of outer shaft lumen  106 .  
         [0039]     Filter manipulating system  100  of  FIG. 4  may preferably be used to retrieve filter  126  from blood vessel  128 . For example, filter  126  may be retrieved from blood vessel  128  by selectively grasping guidewire  130  proximate filter  126  and expanding longitudinally collapsible portion  124  by pushing distally on slider  154 . By expanding longitudinally collapsible portion  124 , distal portion  122  of outer shaft  104  may be urged over filter  126  so that filter  126  is disposed within outer shaft lumen  106 . In a preferred embodiment, filter  126  assumes an expanded configuration when it is disposed within blood vessel  128  and assumes a contracted configuration when it is disposed within outer shaft lumen  106  of catheter  102 . Filter manipulating system  100  may preferably also be used to deploy a filter within a blood vessel.  
         [0040]      FIG. 5  is a partial cross-sectional view of a filter manipulating system  200  in accordance with an additional exemplary embodiment of the present invention. Filter manipulating system  200  comprises a catheter  202  including an outer shaft  204  defining an outer shaft lumen  206 . An inner shaft  208  is slidingly disposed within outer shaft lumen  206 .  
         [0041]     Outer shaft  204  includes a proximal portion  220 , a distal portion  222 , and a longitudinally collapsible portion  224  disposed between proximal portion  220  and distal portion  222 . A wall  262  of proximal portion  220  of outer shaft  204  defines a proximal guidewire port  264 . Catheter  202  also includes a tubular member  266  having a first end  270  fixed to wall  262  of proximal portion  220  of outer shaft  204 , and a second end  272  disposed within outer shaft lumen  206  proximate inner shaft  208 . Tubular member  266  defines a guidewire lumen  268  that is in fluid communication with proximal guidewire port  264 .  
         [0042]     Various embodiments of proximal guidewire port  264  are possible without deviating from the spirit and scope of the present invention. For example, proximal guidewire port  264  may be defined by wall  262  of proximal portion  220  of outer shaft  204 . By way of a second example, proximal guidewire port  264  may be defined by first end  270  of tubular member  266 .  
         [0043]     In  FIG. 5 , it may be appreciated that inner shaft  208  of catheter  202  defines an inner shaft lumen  232 . A wall of inner shaft  208  defines an aperture  274  that is in fluid communication with inner shaft lumen  232 . In  FIG. 5 , a guidewire  230  is shown extending through proximal guidewire port  264 , guidewire lumen  268 , aperture  274 , and a portion of inner shaft lumen  232 .  
         [0044]     Filter manipulating system  200  includes a stop mechanism  234  for selectively limiting the longitudinal movement of guidewire  230  relative to proximal portion  220  of outer shaft  204 . In the embodiment of  FIG. 5 , stop mechanism  234  includes a gripper  236  that is preferably adapted to selectively grasp guidewire  230 . In the embodiment of  FIG. 5 , gripper  236  comprises a collet  238 . Collet  238  preferably defines a distal guidewire port  276 . In  FIG. 5 , guidewire  230  is shown extending through distal guidewire port  276 , a portion of inner shaft lumen  232 , aperture  274 , guidewire lumen  268 , and proximal guidewire port  264 .  
         [0045]     In the embodiment of  FIG. 5 , distal guidewire port  276  is disposed proximally of a distal end  260  of outer shaft  204 , and proximal guidewire port  264  is disposed proximally of distal guidewire port  276 . In  FIG. 5 , it may be appreciated that distal guidewire port  276  and proximal guidewire port  264  are separated by a longitudinal distance. In a preferred embodiment, the longitudinal distance between proximal guidewire port  264  and distal guidewire port  276  is less than about 55 centimeters. In a particularly preferred embodiment, the longitudinal distance between proximal guidewire port  264  and distal guidewire port  276  is less than about 45 centimeters. In an especially preferred embodiment, the longitudinal distance between proximal guidewire port  264  and distal guidewire port  276  is less than about 35 centimeters.  
         [0046]     In the embodiment of  FIG. 5 a  filter  226  of filter manipulating system  200  is disposed within a portion of outer shaft lumen  206  defined by distal portion  222  of outer shaft  204 . In the embodiment of  FIG. 5 , filter  226  is in a contracted configuration. Catheter  202  of filter manipulating system  200  may preferably be used to deploy filter  226  within a blood vessel  228 . Filter  226  may be deployed, for example, by grasping guidewire  230  proximate filter  226  and contracting longitudinally collapsible portion  224 . This may cause distal portion  222  of outer shaft  204  to be drawn away from filter  226  so that filter  226  is disposed outside of outer shaft lumen  206 . In a preferred embodiment, filter  226  assumes an expanded configuration when it is disposed outside of outer shaft lumen  206  and assumes a contracted configuration when it is disposed within outer shaft lumen  206  of catheter  202 . Filter manipulating system  200  may also preferably be used to retrieve a filter that is disposed within a blood vessel.  
         [0047]      FIG. 6  is an additional partial cross-sectional view of the filter manipulating system  200  of  FIG. 5 . In the embodiment of  FIG. 6 , filter  226  is disposed within blood vessel  228 . Filter  226  may be retrieved, for example, by grasping guidewire  230  with gripper  236  and expanding longitudinally collapsible portion  224  of outer shaft  204 . In a preferred embodiment, filter  226  assumes an expanded configuration when it is disposed within blood vessel  228  and assumes a contracted configuration when it is disposed within outer shaft lumen  206  of catheter  202 .  
         [0048]     In  FIG. 6 , it may be appreciated that an articulating rod  250  is disposed within outer shaft lumen  206  defined by outer shaft  204 . A distal end of articulating rod  250  is fixed to a ring  252 . Ring  252  is preferably fixed to distal portion  222  of outer shaft  204  distally of longitudinally collapsible portion  224 . The proximal end of articulating rod  250  is fixed to a slider  254 . Slider  254  is disposed in sliding engagement with a hub  256  that is disposed about a proximal end  258  of outer shaft  204 . In a preferred embodiment, slider  254  and articulating rod  250  may be used to selectively collapse longitudinally collapsible portion  224  of outer shaft  204 .  
         [0049]     A distal end of a guidewire  230  is shown fixed to filter  226 . In the embodiment of  FIG. 6 , guidewire  230  extends through distal guidewire port  276 , a portion of inner shaft lumen  232 , aperture  274 , guidewire lumen  268 , and proximal guidewire port  264 . Stop mechanism  234  may preferably be used to selectively grasp guidewire  230  at a location proximate filter  226 .  
         [0050]      FIG. 7  is a partial cross-sectional view of a filter manipulating system  300  in accordance with an exemplary embodiment of the present invention. Filter manipulating system  300  includes a catheter  302  having an outer shaft  304  defining an outer shaft lumen  306 . Outer shaft  304  includes a proximal portion  320 , a distal portion  322 , and a longitudinally collapsible portion  324  disposed between proximal portion  320  and distal portion  322 . In the embodiment of  FIG. 7 a  filter  326  of filter manipulating system  300  is disposed within a portion of outer shaft lumen  306  defined by distal portion  322  of outer shaft  304 . In the embodiment of  FIG. 7 , filter  326  is in a contracted configuration.  
         [0051]     Filter manipulating system  300  may preferably be used to deploy filter  326  within a blood vessel  328 . Filter manipulating system  300  may also preferably be used to retrieve a filter that is disposed within a blood vessel. In a preferred embodiment, filter  326  assumes an expanded configuration when it is disposed within blood vessel  328  and assumes a contracted configuration when it is disposed within outer shaft lumen  306  of catheter  302 .  
         [0052]     Filter manipulating system  300  of  FIG. 7  includes an inner shaft  308  that is slidingly disposed within outer shaft lumen  306 . A guidewire  330  is slidingly disposed within an inner shaft lumen  332  defined by inner shaft  308 . The longitudinal movement of guidewire  330  relative to inner shaft  308  may be selectively limited by a stop mechanism  334  of filter manipulating system  300 . In the embodiment of  FIG. 7 , stop mechanism  334  includes a gripper portion  378  of inner shaft  308  that is adapted to selectively grasp guidewire  330 .  
         [0053]      FIG. 8  is an enlarged cross-sectional view of a portion of filter manipulating system  300  of  FIG. 7 . In  FIG. 8 , gripper portion  378  of inner shaft  308  is shown having an at rest shape. Gripper portion  378  of inner shaft  308  preferably also has a contracted shape in which gripper portion  378  of inner shaft  308  grasps guidewire  330 .  
         [0054]     In  FIG. 8  it may be appreciated that gripper portion  378  of inner shaft  308  includes a plurality of jaws  340 , each having a tapered portion  342  and a hinge portion  344 . In may also be appreciated that stop mechanism  334  includes a closing sleeve  380  having a mating taper  346 . In the embodiment of  FIG. 8 , closing sleeve  380  is preferably fixed to proximal portion  320  of outer shaft  304 . In a preferred embodiment, relative movement between inner shaft  308  and proximal portion  320  of outer shaft  304  may be used to selectively urge jaws  340  of gripper portion  378  of inner shaft  308  against guidewire  330 . In the embodiment of  FIG. 8 , urging inner shaft  308  proximally relative to proximal portion  320  of outer shaft  304  will preferably cause jaws  340  of gripper portion  378  of inner shaft  308  to grasp guidewire  330 .  
         [0055]      FIG. 9  is an additional enlarged cross-sectional view of the portion of filter manipulating system  300  shown in  FIG. 8 . In the embodiment of  FIG. 9  inner shaft  308  has been moved proximally relative to outer shaft  304  and jaws  340  of gripper portion  378  of inner shaft  308  have been urged against guidewire  330 . In the embodiment of  FIG. 9 , gripper portion  378  of inner shaft  308  has been urged into a contracted shape.  
         [0056]     In  FIG. 9  it may also be appreciated that closing sleeve  380  defines a hole  348 . An articulating rod  350  is shown extending through hole  348 . Articulating rod  350  may preferably be used to selectively collapse and expand longitudinally collapsible portion  324  of outer shaft  304 .  
         [0057]     Referring again to  FIG. 7 , it may be appreciated that a distal end of articulating rod  350  is fixed to a ring  352 . Ring  352  is preferably fixed to distal portion  322  of outer shaft  304  distally of longitudinally collapsible portion  324 . The proximal end of articulating rod  350  is fixed to a slider  354 . Slider  354  is disposed in sliding engagement with a hub  356  that is disposed about a proximal end  358  of outer shaft  304 . In a preferred embodiment, slider  354  and articulating rod  350  may be used to selectively collapse and expand longitudinally collapsible portion  324  of outer shaft  304 .  
         [0058]      FIG. 10  is an additional partial cross-sectional view of the filter manipulating system  300  of  FIG. 7 . In the embodiment of  FIG. 10 , longitudinally collapsible portion  324  of outer shaft  304  has been collapsed by urging slider  354  proximally relative to hub  356 . In the embodiment of  FIG. 10 , distal end  360  of outer shaft  304  is located proximally of filter  326  and filter  326  is disposed outside of outer shaft lumen  306 . In  FIG. 10  it may be appreciated that filter  326  is free to assume an expanded configuration when it is outside of outer shaft lumen  306 .  
         [0059]     Filter manipulating system  300  of  FIG. 10  may preferably be used to retrieve filter  326  from blood vessel  328 . For example, filter  326  may be retrieved from blood vessel  328  by selectively grasping guidewire  330  proximate filter  326  and expanding longitudinally collapsible portion  324  by pushing distally on slider  354 . By expanding longitudinally collapsible portion  324 , distal portion  322  of outer shaft  304  may be urged over filter  326  so that filter  326  is disposed within outer shaft lumen  306 . In a preferred embodiment, filter  326  assumes an expanded configuration when it is disposed within blood vessel  328  and assumes a contracted configuration when it is disposed within outer shaft lumen  306  of catheter  302 . Filter manipulating system  300  may preferably also be used to deploy a filter within a blood vessel.  
         [0060]      FIG. 11  is a partial cross-sectional view of a filter manipulating system  400  in accordance with an additional exemplary embodiment of the present invention. Filter manipulating system  400  comprises a catheter  402  including an outer shaft  404  defining an outer shaft lumen  406 . Outer shaft  404  includes a proximal portion  420 , a distal portion  422 , and a longitudinally collapsible portion  424  disposed between proximal portion  420  and distal portion  422 . A wall  462  of proximal portion  420  of outer shaft  404  defines a proximal guidewire port  464 . Catheter  402  also includes a tubular member  466  having a first end  470  fixed to wall  462  of proximal portion  420  of outer shaft  404 , and a second end  472  disposed within outer shaft lumen  406  proximate inner shaft  408 . Tubular member  466  defines a guidewire lumen  468  that is in fluid communication with proximal guidewire port  464 .  
         [0061]     Various embodiments of proximal guidewire port  464  are possible without deviating from the spirit and scope of the present invention. For example, proximal guidewire port  464  may be defined by wall  462  of proximal portion  420  of outer shaft  404 . By way of a second example, proximal guidewire port  464  may be defined by first end  470  of tubular member  466 .  
         [0062]     Filter manipulating system  400  of  FIG. 11  includes an inner shaft  408  that is slidingly disposed within outer shaft lumen  406 . In  FIG. 11 , it may be appreciated that inner shaft  408  of catheter  402  defines an inner shaft lumen  432 . A wall of inner shaft  408  defines an aperture  474  that is in fluid communication with inner shaft lumen  432 . In  FIG. 11 , a guidewire  430  is shown extending through proximal guidewire port  464 , guidewire lumen  468 , aperture  474 , and a portion of inner shaft lumen  432 .  
         [0063]     In the embodiment of  FIG. 11 , the longitudinal movement of guidewire  430  relative to inner shaft  408  may be selectively limited by a stop mechanism  434  of filter manipulating system  400 . Stop mechanism  434  of  FIG. 11  includes a gripper portion  478  of inner shaft  408  that is adapted to selectively grasp guidewire  430 . Gripper portion  478  of inner shaft  408  preferably defines a distal guidewire port  476 . In  FIG. 11 , guidewire  430  is shown extending through distal guidewire port  476 , a portion of inner shaft lumen  432 , aperture  474 , guidewire lumen  468 , and proximal guidewire port  464 .  
         [0064]     In the embodiment of  FIG. 11 , distal guidewire port  476  is disposed proximally of a distal end  460  of outer shaft  404 , and proximal guidewire port  464  is disposed proximally of distal guidewire port  476 . In  FIG. 11 , it may be appreciated that distal guidewire port  476  and proximal guidewire port  464  are separated by a longitudinal distance. In a preferred embodiment, the longitudinal distance between proximal guidewire port  464  and distal guidewire port  476  is less than about 55 centimeters. In a particularly preferred embodiment, the longitudinal distance between proximal guidewire port  464  and distal guidewire port  476  is less than about 45 centimeters. In an especially preferred embodiment, the longitudinal distance between proximal guidewire port  464  and distal guidewire port  476  is less than about 35 centimeters.  
         [0065]     In the embodiment of  FIG. 11 a  filter  426  of filter manipulating system  400  is disposed within a portion of outer shaft lumen  406  defined by distal portion  422  of outer shaft  404 . In the embodiment of  FIG. 11 , filter  426  is in a contracted configuration. Catheter  402  of filter manipulating system  400  may preferably be used to deploy filter  426  within a blood vessel  428 . Filter  426  may be deployed, for example, by grasping guidewire  430  proximate filter  426  and contracting longitudinally collapsible portion  424 . This may cause distal portion  422  of outer shaft  404  to be drawn away from filter  426  so that filter  426  is disposed outside of outer shaft lumen  406 . In a preferred embodiment, filter  426  assumes an expanded configuration when it is disposed outside of outer shaft lumen  406  and assumes a contracted configuration when it is disposed within outer shaft lumen  406  of catheter  402 . Filter manipulating system  400  may also preferably be used to retrieve a filter that is disposed within a blood vessel.  
         [0066]      FIG. 12  is an additional partial cross-sectional view of the filter manipulating system  400  of  FIG. 11 . In the embodiment of  FIG. 12 , filter  426  is disposed within blood vessel  428 . Filter  426  may be retrieved, for example, by grasping guidewire  430  with gripper portion  478  of inner shaft  408  and expanding longitudinally collapsible portion  424  of outer shaft  404 . In a preferred embodiment, filter  426  assumes an expanded configuration when it is disposed within blood vessel  428  and assumes a contracted configuration when it is disposed within outer shaft lumen  406  of catheter  402 .  
         [0067]     In  FIG. 12 , it may be appreciated that an articulating rod  450  is disposed within outer shaft lumen  406  defined by outer shaft  404 . A distal end of articulating rod  450  is fixed to a ring  452 . Ring  452  is preferably fixed to distal portion  422  of outer shaft  404  distally of longitudinally collapsible portion  424 . The proximal end of articulating rod  450  is fixed to a slider  454 . Slider  454  is disposed in sliding engagement with a hub  456  that is disposed about a proximal end  458  of outer shaft  404 . In a preferred embodiment, slider  454  and articulating rod  450  may be used to selectively collapse longitudinally collapsible portion  424  of outer shaft  404 .  
         [0068]     A distal end of a guidewire  430  is shown fixed to filter  426 . In the embodiment of  FIG. 12 , guidewire  430  extends through distal guidewire port  476 , a portion of inner shaft lumen  432 , aperture  474 , guidewire lumen  468 , and proximal guidewire port  464 . Stop mechanism  434  may preferably be used to selectively grasp guidewire  430  at a location proximate filter  426 .  
         [0069]      FIG. 13  is a partial cross-sectional view of a filter manipulating system  500  in accordance with an additional exemplary embodiment of the present invention. Filter manipulating system  500  comprises a catheter  502  including an outer shaft  504  defining an outer shaft lumen  506 . Outer shaft  504  includes a proximal portion  520 , a distal portion  522 , and a longitudinally collapsible portion  524  disposed between proximal portion  520  and distal portion  522 . A wall  562  of proximal portion  520  of outer shaft  504  defines a proximal guidewire port  564 . Catheter  502  also includes a tubular member  566  having a first end  570  fixed to wall  562  of proximal portion  520  of outer shaft  504 , and a second end  572  preferably fixed to a stop member  582 . Stop member  582  defines a distal guidewire port  576 . Tubular member  566  defines a guidewire lumen  568  that is in fluid communication with distal guidewire port  576  and proximal guidewire port  564 . In  FIG. 13 , guidewire  530  is shown extending through distal guidewire port  576 , guidewire lumen  568 , and proximal guidewire port  564 .  
         [0070]     In the embodiment of  FIG. 13 , longitudinal movement of guidewire  530  relative to stop member  582  may be selectively limited by a stop mechanism  534  of filter manipulating system  500 . Stop mechanism  534  of  FIG. 13  includes stop member  582  and a stop  584  that is preferably fixed to guidewire  530 . In the embodiment of  FIG. 13 , stop  584  comprises a radial enlargement. In a preferred embodiment, stop  584  has an outer radial extent of about 0.014 inches and guidewire  530  has an outer radial extent of about 0.010 inches. In  FIG. 13 , stop  584  is shown seated against stop member  582 .  
         [0071]     In the embodiment of  FIG. 13 , distal guidewire port  576  is disposed proximally of a distal end  560  of outer shaft  504 , and proximal guidewire port  564  is disposed proximally of distal guidewire port  576 . In  FIG. 13 , it may be appreciated that distal guidewire port  576  and proximal guidewire port  564  are separated by a longitudinal distance. In a preferred embodiment, the longitudinal distance between proximal guidewire port  564  and distal guidewire port  576  is less than about 55 centimeters. In a particularly preferred embodiment, the longitudinal distance between proximal guidewire port  564  and distal guidewire port  576  is less than about 45 centimeters. In an especially preferred embodiment, the longitudinal distance between proximal guidewire port  564  and distal guidewire port  576  is less than about 35 centimeters.  
         [0072]     In the embodiment of  FIG. 13 a  filter  526  of filter manipulating system  500  is disposed within a portion of outer shaft lumen  506  defined by distal portion  522  of outer shaft  504 . In the embodiment of  FIG. 13 , filter  526  is in a contracted configuration. Catheter  502  of filter manipulating system  500  may preferably be used to deploy filter  526  within a blood vessel  528 . Filter  526  may be deployed, for example, by contracting longitudinally collapsible portion  524 . This may cause distal portion  522  of outer shaft  504  to be drawn away from filter  526  so that filter  526  is disposed outside of outer shaft lumen  506 . In a preferred embodiment, filter  526  assumes an expanded configuration when it is disposed outside of outer shaft lumen  506  and assumes a contracted configuration when it is disposed within outer shaft lumen  506  of catheter  502 . Filter manipulating system  500  may also preferably be used to retrieve a filter that is disposed within a blood vessel.  
         [0073]      FIG. 14  is an additional partial cross-sectional view of the filter manipulating system  500  of  FIG. 13 . In the embodiment of  FIG. 14 , filter  526  is disposed within blood vessel  528 . In a preferred embodiment, filter  526  assumes an expanded configuration when it is disposed within blood vessel  528  and assumes a contracted configuration when it is disposed within outer shaft lumen  506  of catheter  502 .  
         [0074]     In  FIG. 14 , it may be appreciated that an articulating rod  550  is disposed within outer shaft lumen  506  defined by outer shaft  504 . A distal end of articulating rod  550  is fixed to a ring  552 . Ring  552  is preferably fixed to distal portion  522  of outer shaft  504  distally of longitudinally collapsible portion  524 . The proximal end of articulating rod  550  is fixed to a slider  554 . Slider  554  is disposed in sliding engagement with a hub  556  that is disposed about a proximal end  558  of outer shaft  504 . In a preferred embodiment, slider  554  and articulating rod  550  may be used to selectively collapse longitudinally collapsible portion  524  of outer shaft  504 .  
         [0075]     Having thus described the preferred embodiments of the present invention, those of skill in the art will readily appreciate that yet other embodiments may be made and used within the scope of the claims hereto attached. Numerous advantages of the invention covered by this document have been set forth in the foregoing description. It will be understood, however, that this disclosure is, in many respects, only illustrative. Changes may be made in details, particularly in matters of shape, size, and arrangement of parts without exceeding the scope of the invention. The invention&#39;s scope is, of course, defined in the language in which the appended claims are expressed.