For bare-metal stents, the overall one-year rate of narrowing or in-stent restenosis requiring re-intervention is about 10-15%. Using drug-eluting stents cuts this risk by about two-thirds. If your artery has indeed narrowed enough at the site of stent placement to cause symptoms, the preferred method of treatment is to place a drug-eluting stent inside of the bare-metal stent. The original stent cannot be removed, since it was deployed with considerable pressure against the wall of the artery, and after awhile, your bodys cells grow in and around the stent, incorporating it into the vessel wall. The choice of whether or not to place new stent(s) in the previously stented artery is a complex decision, and depends on your symptoms, possibly the results of an imaging stress test, and the severity of restenosis on angiography.