Patent ID: 7887561

Claim:
A method of implanting a vein filter in the inferior vena cava of a patient comprising: inserting through a femoral vein, superior vena cava or an internal jugular vein a catheter having a filter positioned therein in a collapsed configuration so that a first, second and third wire of the filter are in a substantially elongated configuration; delivering cold saline into the catheter to maintain the filter in the collapsed configuration; releasing the filter from the catheter to enable the filter to move to an expanded configuration in response to warming by exposure to body temperature, the step of releasing the filter causing the filter to move to the expanded configuration such that a pair of axially spaced looped mounting portions, each having a converging region extending from a respective first and second sleeve, expand to a first diameter to contact the vessel, and several of the looped mounting portions form an open loop region that extends from a first side of a longitudinal axis of the filter to a second side of the longitudinal axis, and further wherein the step of releasing the filter causes a pair of axially spaced looped filter portions, each having a converging region extending from a respective opposite end of a third cylindrical sleeve positioned between the filter portions, to expand to a second diameter smaller that the larger first diameter, with the looped filter portions being axially spaced from the looped mounting portions in the vessel, and the mounting portions being at a proximalmost end portion and at a distalmost end portion of the filter and the filter portion converging regions positioned between the mounting portions and progressively increasing in diameter, wherein the second smaller diameter filter portions are only positioned closer to a center of the filter than the first larger diameter looped mounted portions, wherein the wires extend from the first sleeve to one of the sides of the longitudinal axis then loop to extend to the other side of the longitudinal axis and then loop to extend back to the other side of the longitudinal axis and then extend into the third cylindrical sleeve, wherein the wires form loops which are out of phase with the loops of adjacent wires, the wires containing multiple points of inflection.