Implantable self-cleaning blood filters

Abstract

A blood filter device having occlusion-resistant characteristics. The occlusion-resistant characteristics decrease the likelihood of the filter being blocked by thrombi. The filter device includes at least one anchor portion for anchoring the filter device within an aortic branch artery, and a filter portion for filtering thrombi from the blood entering the artery. The filter portion includes an open channel at an open end that, in an implanted configuration, flares outward to increase the width of the filter portion. The open end may accommodate passage of surgical instruments into the artery and may enable blood flow to bypass the filter should the filter become heavily occluded.

1 .- 11 . (canceled) 
     
     
         12 . A blood filter, comprising:
 a body including a porous wall and defining a curved cylinder about a curved body axis, said body including:   an anchor portion defining a flow outlet port at a first end of said body; and   a filter portion that extends from said anchor portion and includes an elbow portion that extends in a direction lateral to said anchor portion and an elongated extension portion that extends from said elbow portion, said elongated extension portion defining a second end of said body, said second end defining a bypass aperture at an open end, said filter portion defining a slot that extends along said elongated extension portion, said elongated extension portion thereby defining a channel having a channel opening at a lateral end of said filter portion,   wherein, in an implanted configuration, said channel opening at said lateral end of said filter portion flares outward to define a fanned filter portion that enlarges a width of said elongated extension portion.   
     
     
         13 . The blood filter of  claim 12 , wherein said filter portion is so dimensioned as to extend from an ostium of a first artery to cover an ostium of an adjacent artery. 
     
     
         14 . The blood filter of  claim 13 , wherein, in said implanted configuration, said fanned filter portion defines a flap configured to lay over an ostium of an adjacent artery. 
     
     
         15 . The blood filter of  claim 13 , wherein said elongated extension portion is so dimensioned to extend from said ostium of said first artery to cover ostia of more than one artery. 
     
     
         16 . The blood filter of  claim 15 , wherein, in said implanted configuration, said fanned filter portion defines a flap configured to lay over ostia of more than one artery. 
     
     
         17 . The blood filter of  claim 12 , wherein said slot extends through said elbow-shaped portion and into said anchor portion. 
     
     
         18 . The blood filter of  claim 12 , wherein said porous wall at said anchor portion defines a porosity in a range of 80% to 95% inclusive. 
     
     
         19 . The blood filter of  claim 12 , wherein said elongated extension portion includes a superior face that defines a first porosity from said bypass aperture to said elbow portion and an inferior face opposite said superior face that defines a second porosity from said bypass aperture to said elbow portion, said first porosity being greater than said second porosity. 
     
     
         20 . The blood filter of  claim 12 , wherein said body comprises a material selected from the group consisting of stainless steel, platinum, platinum-iridium alloys, nickel-cobalt alloys, nickel-cobalt-chromium alloys, nickel-titanium alloys, magnesium based alloys, polyethylene terephthalate, polyurethane, polylactic acid based polymers, shape memory alloy, bio-absorbable alloy, and bio-absorbable polymer. 
     
     
         21 . The blood filter of  claim 12 , wherein said porous wall of said body is a meshed structure. 
     
     
         22 . The blood filter of  claim 12 , wherein said porous wall at said filter portion defines an average pore size that is in a range of 40 μm to 1000 μm inclusive. 
     
     
         23 . The blood filter of  claim 22 , wherein said porous wall at said anchor portion defines an average pore size that is in a range of 800 μm to 5000 μm inclusive. 
     
     
         24 . The blood filter of  claim 12 , wherein a porosity of said porous wall varies axially along said curved body axis. 
     
     
         25 . The blood filter of  claim 12 , wherein, prior to implantation, said channel is narrower than a maximum width of said filter portion, and said channel defines said maximum width of said filter portion in said implanted configuration. 
     
     
         26 . A method for implanting a blood filter that includes a filter portion and an anchor portion, said filter portion including an elbow portion and an extension portion, said elbow portion depending from said anchor portion, said extension portion defining a channel having an open end prior to implantation, the method comprising:
 disposing said anchor portion in a first artery of an aortic arch;   orienting said open end of said filter portion in a downstream direction of a blood flow in said aortic arch; and   spreading said open end of said channel to define a fanned filter portion.   
     
     
         27 . The method of  claim 26 , comprising placing said channel in contact with a wall of said aortic arch. 
     
     
         28 . The method of  claim 26 , wherein said extension portion defines a bypass aperture at a proximal end after the step of spreading. 
     
     
         29 . The method of  claim 26 , wherein said fanned filter portion in the step of spreading defines a flap that lays over an ostium of an adjacent artery. 
     
     
         30 . The method of  claim 26 , wherein said fanned filter portion in the step of spreading defines a flap that lays over ostia of more than one adjacent artery. 
     
     
         31 . The method of  claim 30 , comprising lifting said fanned filter portion for access to said adjacent artery. 
     
     
         32 . The method of  claim 26 , comprising orienting said filter portion to cover an ostium of an adjacent artery. 
     
     
         33 . The method of  claim 26 , comprising orienting said extension portion of said filter portion to cover ostia of more than one artery. 
     
     
         34 . The method of  claim 26 , wherein, prior to implantation, said channel is narrower than a maximum width of said filter portion and, after the step of spreading, said channel defines said maximum width of said filter portion.