Patent ID: 9730781
Date: 2017-08-15
CPC Classifications: A61B,A61F

Claim:
1. A blood filter and removal apparatus for removing a blood filter from a vessel wall comprising: a) a blood filter adapted to be secured to a blood vessel wall, having a central, longitudinal axis the filter having a hub proximally positioned and a plurality of distally positioned circumferentially spaced legs extending distally from the hub, each leg having a leg distal end with a vessel wall engaging anchor that is configured to anchor the filter to the vessel wall in a filter deployed position; b) a catheter having a diameter and a catheter lumen defining a longitudinal axis; c) an elongate extraction device configured to be positioned within the catheter lumen and to move longitudinally and rotationally with respect to the catheter, said extraction device having a tubular member with a collapsible distal conical portion and a rod with a distal end; d) the extraction device including at least one helical wire coupled to the distal end of the rod, wherein the helical wire has a longitudinal axis and the rod has a longitudinal axis, and the longitudinal axis of the helical wire is coincident with the longitudinal axis of the rod; e) wherein in an initial leg removal position the helical extraction wire engages the filter legs and the legs have a first diameter that is configured to place each anchor in the vessel wall, wherein in a final leg removal position the helical wire collapses the filter legs to a second diameter that is smaller than the said first diameter, wherein movement of the filter legs from the initial leg removal position to the final leg removal position is effected by rotation of the extraction device rod and helical wire connected to the filter legs at a position distally of the hub; f) wherein in the initial leg removal position, the helical wire has an overall diameter that is greater than the diameter of the catheter and less than the diameter of the vessel; and g) wherein the said final leg removal position disengages the anchors from the vessel wall by collapsing the filter legs toward said filter longitudinal axis.