Embolus blood clot filter with floating filter basket

Abstract

A blood filter device for placement in a blood vessel including a plurality of anchor members disposed radially and extending angularly about a first hub. A filter basket is preferably positioned upstream from the anchor members. The anchor members each include a hook configured to penetrate the vessel wall to prevent longitudinal movement due to blood flow. The filter basket is made up of a number of filter members configured to retain blood clots within the basket without completely blocking blood flow or applying additional force to vessel walls. Portions of the filter members may project radially outward to position the basket near the vessel centerline, but the filter basket preferably does not include hooks or anchors for anchoring the filter basket to the blood vessel.

1 - 26 . (canceled) 
     
     
         27 . A filter to be placed in a flow of blood through a blood vessel having a blood vessel wall, the filter comprising:
 a) a filter body that comprises one or more helical members surrounding an interior basket area and having an initial diameter, the body having first and second end portions and a first length in between said end portions;   b) one or more pads on the second end portion of each of the helical members, each pad extending a distance radially away from the helical member initial diameter, each pad positioned to engage the blood vessel wall;   c) the body being expandable to an expanded position of a second diameter responsive to a filling of the interior basket with emboli, wherein said second diameter is larger than the first diameter and wherein said body length is shortened to a second smaller length that is smaller than the said first length in said expanded position.   
     
     
         28 . The filter of  claim 27 , wherein one or more of the pads have hooks. 
     
     
         29 . The filter of  claim 27 , wherein there are multiple of said helical members, each having a said pad. 
     
     
         30 . The filter of  claim 29 , wherein the helical members are equi-angularly spaced apart. 
     
     
         31 . The filter of  claim 27  further comprising a head with a diameter that is smaller than said initial diameter, each said helical member attached to said head. 
     
     
         32 . The filter of  claim 27 , wherein each helical member is a wire. 
     
     
         33 . The filter of  claim 32  wherein each pad is a part of said wire. 
     
     
         34 . The filter of  claim 32  wherein the said wire has a free end portion. 
     
     
         35 . The filter of  claim 34  wherein the pad is a part of said wire free end portion. 
     
     
         36 . A filter to be placed in a flow of blood through a blood vessel, the filter comprising:
 a) a hub deposed along a longitudinal axis;   b) one or more helical members joined to the hub;   c) the helical member or members defining a filter basket having an initial diameter, a filter basket interior and a filter basket opening, the filter basket configured so that the filter basket's opening faces away from the hub;   d) wherein the basket opening is receptive of emboli that expand the basket once the basket interior collects a plurality of emboli.   
     
     
         37 . The filter according to  claim 36  wherein each helical member is a wire. 
     
     
         38 . The filter according to  claim 37 , wherein each of the wires has a pad that extends beyond said initial diameter. 
     
     
         39 . A filter to be placed in a flow of blood through a blood vessel having a blood vessel wall, the filter comprising:
 a) a hub disposed along a longitudinal axis;   b) a plurality of equi-angularly spaced apart helical members projecting from the hub, at least some of the plurality of helical members including a pad configured to engage the wall of the blood vessel when the filter is positioned in the blood vessel and expanded to an expanded diameter;   c) the helical members defining a filter basket having a basket periphery of an initial diameter that surrounds a basket opening into which blood can flow to generate said expanded diameter to a larger diameter.   
     
     
         40 . The filter of  claim 39  wherein each said pad has a hook. 
     
     
         41 . The filter of  claim 39  wherein each helical member is a wire. 
     
     
         42 . The filter of  claim 39  wherein the hub has a diameter that is much smaller than the said initial diameter. 
     
     
         43 . The filter of  claim 39  wherein each helical member has first and second end portions, the first end portion attached to the hub, the second end portion being a free end portion and wherein each helical member forms a part of said basket with said hub. 
     
     
         44 . The filter of  claim 43  wherein said basket has a smaller tapered portion next to the hub. 
     
     
         45 . The filter of  claim 39  wherein each helical member extends around said longitudinal axis at least 180 degrees. 
     
     
         46 . The filter of  claim 39  wherein each helical member extends around said longitudinal axis at least 270 degrees. 
     
     
         47 . The filter of  claim 39  wherein each helical member extends around said longitudinal axis at least 360 degrees. 
     
     
         48 . The filter of  claim 39  wherein the hub and the helical members are of differing materials. 
     
     
         49 . The filter of  claim 48  wherein the helical members are of a metallic material. 
     
     
         50 . The filter of  claim 48  wherein the hub is of a non-metallic material.