A prosthesis is disclosed for placement across an ostium opening from a main body lumen to a branch body lumen. The prosthesis comprises a radially expansible support at one end, a circumferentially extending link at the other end and at least one frond extending axially therebetween. In some embodiments, the circumferential link can comprise a catheter securement portion and a frond engagement portion. In some embodiments, the frond(s) include a section with a single filament extending between a proximal end and a distal end of the frond.