1. A method for vascular assessment comprising: receiving a plurality of 2D angiographic images of a portion of a vasculature of a subject, and processing said images to produce a stenotic model over the vasculature, said stenotic model having measurements of the vasculature at one or more locations along vessels of the vasculature; obtaining a flow characteristic of the stenotic model; and calculating an index indicative of vascular function, based, at least in part, on the flow characteristic in the stenotic model.