The first use of a coronary stent is typically attributed to and Ulrich Sigwart when they implanted a stent into a patient in Toulouse, France, in 1986. It was used as a scaffold to prevent the vessel from closing and to avoid restenosis in coronary surgery—a condition where scar tissue grows within the stent and interferes with vascular flow. Shortly thereafter, in 1987, Julio Palmaz (known for patenting a balloon-expandable stent ) and Richard Schatz implanted their similar stent into a patient in Germany.