Support frame for an embolic protection device

Abstract

A support 103 for an embolic protection device comprises round wires 116 which may form one or more support hoops for a filter body The circumferential hoop formed by the wires 116 ensures that in the expanded position, the filter body 102 will be supported by the support frame 103 in circumferential apposition with the interior wall of the vasculature. The wires 116 may have a strain distributing linkage element in the form of a loop 120 in. The loop 120 acts as a diameter or circumference adjuster allowing an embolic protection device to adapt to different vessel contours and sizes whilst maintaining apposition with the vessel wall. The strain relieving geometry of the loops enhances the compliance of the bend points without creating a weakened hinge point, thus ensuring that there is no discontinuity in the circumferential seal against the vessel wall.

1 . An embolic protection device comprising: 
 a collapsible filter element for delivery through a vascular system of a patient;    the filter element comprising a collapsible filter body and a filter support for the filter body;    the filter body having an inlet end and an outlet end, the inlet end of the filter body having one or more inlet openings sized to allow blood and embolic material enter the filter body, the outlet end of the filter body having a plurality of outlet openings sized to allow through passage of blood but to retain undesired embolic material within the filter body;    the filter support being movable between a collapsed position for movement through the vascular system, and an extended outwardly projecting position to support the filter body in an expanded position;    the filter support comprising a number of segments at least some of which are interconnected by a strain distributing linking element.    
   
   
       2 . A device as claimed in  claim 1  wherein at least some of the segments are of wire.  
   
   
       3 . A device as claimed in  claim 1  wherein the linking element is of wire.  
   
   
       4 . A device as claimed in  claim 3  wherein the linking element is of the same wire as that of the support segments.  
   
   
       5 . A device as claimed in  claim 1  wherein the linking element extends normally of adjacent segments.  
   
   
       6 . A device as claimed in  claim 1  wherein the linking element extends longitudinally of the axis of the filter.  
   
   
       7 . A device as claimed in  claim 1  wherein the linking element extends radially inwardly of the adjacent segments.  
   
   
       8 . A device as claimed in  claim 1  wherein the linking element comprises a loop.  
   
   
       9 . A device as claimed in  claim 8  wherein the loop is of generally omega shape.  
   
   
       10 . A device as claimed in  claim 1  wherein at least portion of the linking element is radiopaque.  
   
   
       11 . A device as claimed in  claim 1  wherein at least portion of at least some of the support segments are radiopaque.  
   
   
       12 . A device as claimed in  claim 1  wherein the linking element is of multifilament construction.  
   
   
       13 . A device as claimed in  claim 1  wherein at least one of the support segments is of multifilament construction.  
   
   
       14 . A device as claimed in  claim 1  wherein the support frame is defined by at least two wire segments having terminations.  
   
   
       15 . A device as claimed in  claim 14  wherein the terminations of adjacent segments extend generally parallel to one another.  
   
   
       16 . A device as claimed in  claim 14  wherein the terminations of adjacent segments are fixed relative to one another.  
   
   
       17 . A device as claimed in claimed in  claim 1  wherein the support frame is defined by at least two wire segments terminating distally, the distal terminations of adjacent segments being fixed relative to one another and extending generally parallel.  
   
   
       18 . A device as claimed in  claim 1  wherein the support frame is defined by at least two wire segments terminating proximally, the proximal terminations of adjacent segments being fixed relative to one another and extending generally parallel.  
   
   
       19 . A device as claimed in  claim 1  wherein the support frame comprises a support arm for one end of the filter body which extends towards an opposite end of the filter body in the deployed configuration.  
   
   
       20 . A device as claimed in  claim 1  wherein the device comprises a carrier extending longitudinally of the frame.  
   
   
       21 . A device as claimed in  claim 20  comprising a flexible tether extending between the carrier and the support frame.  
   
   
       22 . A device as claimed in  claim 20  wherein the carrier comprises a tubular member.  
   
   
       23 . A device as claimed in  claim 20  wherein the carrier comprises a guidewire.  
   
   
       24 . A device as claimed in  claim 1  wherein the support frame comprises a support hoop.  
   
   
       25 . A device as claimed in any of  claim 1  wherein the filter support comprises a support frame having at least two longitudinally spaced-apart segments.  
   
   
       26 . A device as claimed in  claim 25  wherein the segments are interconnected by at least one flexible linking element.  
   
   
       27 . A device as claimed in  claim 1  wherein the support frame comprises a support arm for one end of the filter body which extends towards an opposite end of the filter body in the deployed configuration.  
   
   
       28 . A device as claimed in  claim 1  wherein the filter support comprises a generally tubular support frame defined by at least one wire.  
   
   
       29 . A device as claimed in  claim 1  wherein the wire element has a round cross-section.  
   
   
       30 . A device as claimed in  claim 1  wherein the wire element has an elongate cross-section with a long dimension and a short dimension.  
   
   
       31 . A device as claimed in  claim 30  wherein the short dimension of the wire element cross-section is aligned substantially along the radial direction of the filter support.  
   
   
       32 . A device as claimed in  claim 1  wherein the wire element is rectangular in cross-section.