An implantable permanent filter assembly (1) for deployment in a bifurcated vessel includes a main vessel and at least two branches. This assembly includes a filtering sleeve (2) formed of an expendable braided framework (20) able to expand from a radially compressed state in a delivery configuration to a radially expanded state. The filtering sleeve extends along an axis and defines a cylindrical lumen devoid of impermeable layer, having a distal end configured to extend toward the branches of the bifurcated vessel and a proximal end configured to extend toward away from the branches of the bifurcated vessel. The braided framework has a plurality of mesh layers (22,23,24) of wires (25) made of biocompatible material, forming a lattice with a plurality of wires of each layers. The lattice, when observed normal with respect to a wall of the implantable endoluminal prosthesis, defines polygonal openings.
