An inferior Vena Cava (“IVC”) filter is formed of two adjacent structures such as polyhedral, each having a number of sides positioned to avoid side-wise contact with the caval wall. The structures form a first filter basket and a second filter basket respectively, with the filter baskets joined by a center structure around a center axis of the IVC filter. In this configuration, the IVC filter advantageously self-aligns within the IVC, while permitting bidirectional or directionally independent deployment, use, and retrieval. While polyhedra may usefully be configured with no sides parallel to the IVC wall to mitigate attachment to the IVC wall, the structures of the filter baskets may also or instead use curved members distal to the center axis that contact the IVC wall only at a single tangent point or area.
