First performed in the mid–1980s, and approved by the U.S. Food and Drug Administration (FDA) in 1994, stenting is a catheter-based procedure in which a small, expandable wire mesh tube (stent) is implanted into a diseased artery as a scaffold to hold it open. Stents can be placed in arteries and veins throughout the body. Coronary stents are designed to be placed into the coronary arteries that lie on the surface of the heart and supply the heart with oxygen-fresh blood. Coronary artery stents have made it possible for physicians to treat diseased coronary arteries with less trauma to the patient than coronary artery bypass graft surgery. As a result of advancing stent design, more patients with more complex disease are candidates for stenting, which reduces the number of surgeries.

Coronary artery stenting is almost always performed in conjunction with other catheter-based procedures, such as balloon angioplasty or atherectomy. These procedures are used to partially reduce the narrowing caused by atherosclerosis. In particular, stenting has been an important advance in balloon angioplasty. Before the introduction of stents, as many as half of all coronary arteries opened with a balloon-tipped catheter narrowed once again after the procedure (restenosis). With today's advanced stents, the restenosis rate has dropped to below 10 percent in some cases. In addition, stents have reduced the risk of sudden, or acute, closure of a coronary artery after angioplasty from 2 to 10 percent to less than 1 percent. Because of the stent's effectiveness, they are now used in the vast majority of balloon angioplasty cases and researchers are continually finding new applications for them.

By its nature, a stent is designed to be a permanent implant. In cases of complex or diffuse disease, multiple or even overlapping stents can be used. Until recently, most stents were made from bare metal. In 2003, however, a new generation of stents was introduced. These stents, called drug-eluting stents, are covered with special drugs that reduced the restenosis rate to its current low rate. Today, drug-eluting stents comprise the majority of stents in clinical use for coronary artery disease. However, new research has indicated that drug-eluting stents may raise the risk of blood clots in certain patients, especially those who discontinue their medications early.

Stents are not affected by metal detectors or most mechanical equipment. The success of a stenting procedure can be compromised by risk factors such as smoking or high cholesterol levels, which could lead to new blockages in the coronary arteries. People receiving stents are strongly encouraged to learn and practice healthy lifestyle behaviors for good heart health.