After President Clinton's Surgery, a Primer on Stents
The stent stays in the artery permanently to improve bloodflow to the heart muscle and relieve symptoms of heart conditions, such as chest pain. Within weeks, the inside lining of the artery grows over the metal surface of the stent. The placement of the stent reduces the risk of the artery's narrowing again, but doesn't prevent it entirely.
Although bypass surgery is necessary when balloon angioplasty or stenting does not solve the problem, more than 70% of coronary angioplasty procedures include stenting. (One study suggests that this figure indicates an overuse of stents.) Some stents are coated with drugs that are released gradually to keep the blood vessel from reclosing. The procedure is not without risk: Patients can develop an allergic reaction to stent material or drug, a blood clot, or a rupture of the vessel during the procedure.
We don't yet know whether Clinton will need to repeat this procedure. But doctors advise heart patients to stay on heart medication, and to control other risk factors -- which mostly means following a healthy lifestyle.