Expandable cages for embolic filtering devices

Abstract

A self-expanding cage for use in conjunction with an embolic filtering device includes a circumferential member adapted to expand from an unexpanded position to a expanded position within the patient's body vessel. A proximal strut and distal strut are attached to the circumferential member to form the cage. A plurality of proximal and distal struts may be attached the circumferential member. Additionally, a second circumferential member can be attached to the first circumferential member. Each circumferential member can be connected by a single or a plurality of connecting struts. One embodiment of the cage utilizes a single wire to form to the cage. A delivery system attached to the single wire cage moves the cage and its associated filter element between the expanded and unexpanded positions through relative movement of the distal delivery system. This can be accomplished by either torquing the guide wire onto which the expandable cage is mounted or by longitudinally moving a tubular member which forms part of the delivery system longitudinally in relation to the guide wire.