Patent ID: 8092484
Filing Date: 2012-01-10
Classification: A61F

Abstract:
1. A filter to be placed in a flow of blood through a blood vessel having a vessel wall, the filter comprising: a) a hub, the hub having first and second end portions and a longitudinal axis; b) a plurality of leg members extending generally in one direction, distally from the hub, each leg member having one end portion connected to said hub and another end portion that is a free end portion spaced away from said hub, wherein only some of said leg members are a first plurality of leg members that are positioned by a resorbable restraint coupled to spring portions of the first plurality of leg members so as to retain the first plurality of the leg members in a first configuration that provides a first spring force that is applied toward the vessel wall in a radially outward direction that is transverse to the longitudinal axis and at a said free end portion of the first plurality of the leg members and wherein at least a portion of the first plurality of leg members forms a first acute angle with the said longitudinal axis; c) a second plurality of leg members that are not retained by a resorbable restraint, wherein a portion of each leg of said second plurality of leg members connects to the hub; and d) wherein when the resorbable restraint has resorbed the first plurality of leg members that were positioned by the resorbable restraint assume a second configuration that rotates said spring portions to form a second acute angle relative to said longitudinal axis that is different from said first acute angle, wherein said second configuration provides a second spring force that is applied toward the vessel wall in a radially outward direction that is transverse to the longitudinal axis and at a free end of the second plurality of leg members, wherein the second spring force is lower than the first spring force so that vessel damage or injury due to continued application of said first spring force is reduced or eliminated.