(CNN) -- A stent is a small scaffolding device that is placed inside blood vessels around the heart. The device, which consists of a metal mesh tube, is a treatment for conditions that involve narrowed or blocked arteries.
This is the device used in a procedure for former President George W. Bush, 67, according to a statement from his office. An annual physical examination in Dallas had revealed a blockage in one of Bush's arteries Monday.
Tuesday, Bush underwent a procedure to have a stent placed in his heart. The former president's spokesman said the procedure was "performed successfully," without complication.
A stent gives support inside the coronary artery, according to the Cleveland Clinic, the top-ranked hospital in the United States for cardiology and heart surgery.
If a patient comes in with symptoms of chest pain with exertion, which has not responded well to medications, or if the patient is having a heart attack, he or she would be considered for a stent, said Dr. Steven Nissen, chair of cardiology at the Cleveland Clinic. They usually go home the next day and do fine.
The technical term for hardening of the arteries is atherosclerosis. This happens when cholesterol and fatty deposits called "plaques" build up on the inner walls of the arteries, which are shaped like hollow tubes, according to the Cleveland Clinic. When the arteries' normal lining deteriorates, and their walls thicken and undergo build-up from fat and plaque, blood has a hard time flowing to the heart.
A heart deprived of adequate blood can't get the oxygen and nutrients necessary for normal function. This leads to chest pain known as angina.
The blockage of one or more coronary arteries can lead to heart attack.
Fortunately, as a treatment, stents can prop arteries back open. At least one million of these procedures are done every year, Nissen said.
The stent is inserted into the artery with a balloon catheter, which is placed over a guide wire.
Doctors inflate the balloon so that the stent enlarges to the size of the artery, holding it open. The stent remains there indefinitely, but the balloon is removed.
This procedure, called angioplasty with stenting, is often recommended for patients with blockages in one or two coronary arteries.
During the procedure, patients are awake with little sedation, Nissen said.
Patients take blood thinning medications up to a year to prevent clots, Nissen said. Eventually, the stent gets covered with tissue and incorporated into the wall of the artery, so patients don't need the blood thinners anymore, he said.
The biggest concern after surgery is injury because of the blood thinners, he added.
The average cost of having a stent inserted is $28,000 in the United States, according to the International Federation of Health Plans, as of 2012.
More details would be needed to make more definitive statements about why Bush needed a stent, Nissen said.
The former president's vice president, Dick Cheney, had surgery to insert a stent in one of his arteries in 2000, shortly after the election. He has had multiple heart attacks, and in 2010 underwent a procedure to have a small pump inserted in his heart to keep the circulation going.
Former President Bill Clinton also underwent a procedure involving stents in 2010. Doctors inserted two stents to restore blood flow to a cornary artery. He had been hospitalized after brief periods of chest discomfort, Dr. Allan Schwartz, cardiologist at New York-Presbyterian Hospital, said at the time.
Clinton had undergone a quadruple bypass surgery in 2004. A bypass graft that was part of that surgery had gotten blocked, Schwartz said.
Chest pain can be a sign of a serious problem. If you experience a sudden, crushing and tightening feeling in your chest, pain that radiates to other areas, or a sharp pain with shortness of breath, call 911.
CNN's Jacque Wilson contributed to this report