A stent is a small stainless steel mesh tube that behaves like scaffolding and gives a narrowed coronary artery support, thus holding it open. A balloon catheter is used to deliver the stent into the narrowed coronary artery then, once in place, the balloon is inflated and the stent expands to the size of the artery and holds it open. The balloon is then deflated and removed, and the stent stays in place permanently.