Patent ID: 6881218

Claim:
A self-centering blood clot filter having an active state and an inactive state for use in a vascular lumen comprising: a cylindrical positioning portion having a plurality of positioning struts adapted to sit against the wall of a vascular lumen, each of said positioning struts having an upstream end and a downstream end, pairs of said positioning struts having their upstream ends connected to provide a plurality of junctions, a filtering portion having a plurality of resilient filter struts, each of said filter struts having an upstream end and a downstream end, said upstream end of each of said filter struts being connected to a separate one of said plurality of junctions of the upstream ends of said positioning struts, this connection being the sole connection between said filter struts and said pairs of said positioning struts, a frangible connecting element connected to said downstream ends of said filter struts to maintain said downstream ends in a central location during the active state within a vascular lumen, said connecting element having a central opening during the active state to allow blood clots less than a predetermined size to pass through said opening near the center of a vascular lumen, said downstream ends of each of said filter struts being independently connected to said connecting element, the breaking of said frangible connector causing said resilient filter struts to flex radially outward against the wall of a vascular lumen to thereby create an inactive state for said filter.