An implantable medical device is described, including a filtering element and radially expandable structure. In one variation, the filtering element may include a pluralit of filaments attached to the structure, the filaments being joined together at a proximal en thereof. The filtering element may include strut members and a hub attached to the proxima end of the filaments. The filaments may be made of suture material. In another variation, the filtering element may include a filter with a plurality of legs, the filter being attached to the support structure via a plurality of filaments.