Remodeling of arterial conduits in coronary grafting

In the initial decade of coronary surgery, serial angiography of internal thoracic artery grafts revealed increased caliber in some, decreased caliber in others, and "string sign" in a few, which was occasionally documented to be reversible. Although we speculated on possible causes of these changes, it was not until discovery of the endothelial role in modulating arterial diameter to maintain shear stress in a narrow range that we began to gain insight into the mechanisms responsible for remodeling of the arterial wall. This review provides a glimpse of the physiology and biology of arterial remodeling and summarizes observations on the various arterial conduits when subjected to flow alterations.