The present invention relates to an
endovascular prosthesis. The
endovascular prosthesis comprises a first expandable portion expandable from a first, unexpanded state to a second, expanded state to urge the first expandable portion against a
vascular lumen and a retractable leaf portion attached to the first expandable portion. The retractable leaf portion comprises at least one spine portion and a plurality of rib portions attached to the spine portion. In one preferred embodiment of the present
endovascular prosthesis, the retractable leaf portion is configured such that a pair of ribs attached on opposite sides of a longitudinally straightened configuration of the spine portion in a plane of view normal to a central axis of the
prosthesis defines a shape, in two dimensions, that is substantially non-circular. In another preferred embodiment of the present endovascular
prosthesis, the retractable leaf portion is configured such that a pair of ribs attached on opposite sides of a longitudinally straightened configuration of the spine portion in a plane of view normal to a central axis of the
prosthesis defines a shape, in two dimensions, through which one straight line can be translated from one side to the other side of the shape so as to
traverse the shape only once at every point along the shape. The rib portions of the present endovascular prosthesis can be designed so as to provide an improved rotational range of proper placement of the prosthesis with respect to the opening of the
aneurysm. In a preferred embodiment, the rotational range may be as much as 45° or more. There is also described a method for delivering an endovascular prosthesis to a bifurcated
artery which can be accomplished using a single guidewire and a single delivery device.