Slideable vascular filter

Abstract

A collapsible medical device that includes a mandrel having a distal end and a stop spaced proximally of the distal end. A proximal length of the mandrel extends proximally of the stop and a distal length of the mandrel extends distally of the stop. A functional element has a radially expandable body and includes proximal and distal sliders. The proximal and distal sliders are slidable along the mandrel independently of one another such that the distance between the proximal slider and distal slider can be varied to effect different configurations of the functional element. In one method of using such a device, urging the mandrel distally causes the stop to exert a distal biasing force on the distal slider, which acts against a restorative force of the functional element to axially elongate the functional element and reduce friction between the functional element and a wall of the vessel.

1 . Apparatus for filtering emboli from blood flowing through a vessel, the apparatus comprising:
 a guide wire having a distal region and a stop fixed on the distal region;   a capture ring disposed for rotation on the guide wire, the stop limiting translation of the capture ring in a proximal direction; and   a filter sac coupled to the capture ring,   wherein, when the filter sac is deployed in the vessel, rotation of the guide wire relative to the capture ring does not displace the filter sac, but advancement of the guide wire in a distal direction causes the stop to abut against the capture ring.   
     
     
         2 . Apparatus for filtering emboli from blood flowing through a vessel, the apparatus comprising:
 a guide wire having a first portion having a first diameter and a second portion having a second diameter greater than the first diameter; and   a filter element having a capture ring disposed for translation on the first portion, the capture ring having an aperture greater in size than the first diameter but smaller in size than the second diameter,   wherein rotation of the guide wire relative to the capture ring does not displace the filter element but advancement of the guide wire in a distal direction causes a distal end of the second portion to abut against the capture ring.   
     
     
         3 . The apparatus of  claim 2  wherein the filter element comprises an expandable sac. 
     
     
         4 . The apparatus of  claim 2  wherein the guide wire further comprises a flange disposed on the distal region having a diameter larger than the diameter of the aperture in the capture ring. 
     
     
         5 . A method of filtering emboli from blood flowing through a vessel, the method comprising:
 providing a guide wire having a distal region including a stop, and a filter element having a capture ring disposed for translation on the guide wire distal of the stop;   transluminally inserting the guide wire and filter element into a vessel;   deploying the filter element to engage a wall of the vessel, the filter element filtering emboli out of blood flowing through the vessel;   advancing a treatment device along the guide wire to treat a portion of the vessel proximal to the location of the filter element, rotation of the guide wire relative to the filter element imparted by the treatment device not displacing the filter element but advancement of the guide wire in a distal direction causes the stop to abut against the capture ring.   
     
     
         6 . The method of  claim 5  further comprising:
 providing a delivery sheath; and 
 compressing the filter element to a contracted state to insert the filter element within the delivery sheath. 
 
     
     
         7 . The method of  claim 5  wherein the filter element comprises an expandable sac, and deploying the filter element comprises expanding the expandable sac so that a perimeter of the expandable sac contacts the wall of the vessel. 
     
     
         8 . Apparatus for filtering emboli from blood flowing through a vessel, the apparatus comprising:
 a guide wire having a distal region and a stop on the distal region;   a ring disposed for rotation on the guide wire, the stop limiting translation of the ring in a proximal direction; and   a filter coupled to the ring,   wherein, when the filter is deployed in the vessel, rotation of the guide wire relative to the ring does not displace the filter, but advancement of the guide wire in a distal direction causes the stop to abut against the ring.   
     
     
         9 . Apparatus for filtering emboli from blood flowing through a vessel, the apparatus comprising:
 a guide wire having a proximal portion having a first diameter and a distal portion having a second diameter less than the first diameter; and   a filter element having a sliding member disposed for translation on the distal portion, the sliding member having an aperture greater in size than the first diameter but smaller in size than the second diameter,   wherein rotation of the guide wire relative to the sliding member does not displace the filter element, but advancement of the guide wire in a distal direction causes the proximal portion to abut against the sliding member.   
     
     
         10 . The apparatus of  claim 9  wherein the filter element comprises an expandable sac. 
     
     
         11 . Apparatus for filtering emboli from blood flowing through a vessel, the apparatus comprising:
 a guide wire having a distal region and a stop on the distal region;   a sliding member disposed for translation on the guide wire, the stop limiting translation of the sliding member in a proximal direction; and   a self-expanding filter sac coupled to the sliding member;   wherein, when the filter sac is deployed in the vessel, rotation of the guide wire relative to the sliding member does not displace the filter sac, but advancement of the guide wire in a distal direction causes the stop to abut against the sliding member.   
     
     
         12 . Apparatus for filtering emboli from blood flowing through a vessel, the apparatus comprising:
 a guide wire having a first portion having a first diameter and a second portion having a second diameter greater than the first diameter; and   a self-expanding filter element having a sliding member disposed for translation on the first portion, the sliding member having an aperture greater in size than the first diameter but smaller in size than the second diameter,   wherein rotation of the guide wire relative to the sliding member does not displace the filter element, but advancement of the guide wire in a distal direction causes the second portion to abut against the sliding member.   
     
     
         13 . The apparatus of  claim 12  wherein the filter element comprises an expandable sac. 
     
     
         14 . The apparatus of  claim 12  wherein the guide wire further comprises a flange disposed on the distal region having a diameter larger than the diameter of the aperture in the capture ring. 
     
     
         15 . A method of filtering emboli from blood flowing through a vessel, the method comprising:
 providing a guide wire having a distal stop, and a filter element having a sliding member disposed for translation on the guide wire distal of the stop;   transluminally inserting the guide wire and filter element into a vessel;   deploying the filter element to engage a wall of the vessel, the filter element filtering emboli out of blood flowing through the vessel;   advancing a treatment device along the guide wire to treat a portion of the vessel proximal to the location of the filter element, rotation of the guide wire relative to the filter element not displacing the filter element, but advancement of the guide wire in a distal direction causing the stop to abut against the sliding member.