Arterial stent. Computer artwork of a stent holding open an artery. Stents are inserted during angioplasty operations to treat stenosis (narrowing) of the artery. In this case the narrowing has been caused by atherosclerosis, the deposition of fatty plaques (yellow) on the artery wall. A stent is inserted by using a balloon catheter to expand the artery. The stent holds the artery open to allow normal blood flow. Stents may be used in other areas of the body also, for example to hold open diseased regions of the intestine or airway.