Like any medical treatment, stents are not successful in all cases. Balloon angioplasty and coronary stents enable the cardiologist to open one or more coronary arteries rapidly and without surgery, and the result is an immediate benefit and a quick recovery. Stents can close, however, in some cases. The closure may be either partial or complete, it may occur suddenly or gradually, and the event may or may not result in chest pain. Such a failure of a stent may be managed by medical treatment, placement of one or more additional stents, or by coronary bypass surgery, either as an emergency or as elective surgery. Coronary bypass surgery requires a longer recovery than angioplasty or stent placement, but its intent is to provide a durable result which will last for years and years.