Patent ID: 8636789

Claim:
A stent graft comprising: a tubular wall of biocompatible graft material having a main lumen extending longitudinally therethrough, a proximal end, a distal end, and a double layer valve between the proximal end and the distal end; the double layer valve comprising an inner layer including a part circumferential sheet of biocompatible graft material, an outer layer including a portion of the wall, and a passageway between the inner layer and the outer layer; an entrance mouth communicating with the main lumen and the passageway, and an exit mouth communicating with the passageway; the inner layer attached to the wall and positioned overlapping the exit mouth; the passageway having a closed condition where the inner layer and the outer layer are in contact and an open condition where the inner layer and the outer layer are spaced apart; the passageway being parallel to the main lumen when in a closed condition; and wherein the stent graft also comprises at least one internal zig zag stent having at least one strut which biases the inner layer radially outward into contact with the outer layer.