An endothelial scaffold may used to form a graft with an endothelial lining or endothelium. The scaffold allows a natural vessel or other endothelial lumen to line a channel of the scaffold to provide an endothelial layer which enhances blood flow through the channel. The channel may have a narrowed section to provide a stenosis. One or more conduits may extend from an exterior portion of the scaffold to an inner surface of the channel. Air may be withdrawn from between the natural vessel and inner surface of the channel via the conduits to cause the endothelial lumen to conform to the inner surface of the channel. A valve may be used to prevent air from reentering the conduits. The graft, including the endothelial lumen, may be implanted into a patient.
