Treatments like the quadruple bypass surgery Clinton had in 2004 last about a decade on average. Then the blood vessels used to create detours around the clogged arteries start to get blocked, too.
One such blockage sent Clinton to the hospital on Thursday. Instead of fixing it, doctors reopened the original clogged artery and placed two mesh props called stents to keep it open.
It's something he's likely to need again, heart experts say.
"We see people who come in like this every four to five years. Essentially, it's a tuneup," said Dr. Cam Patterson, cardiology chief at the University of North Carolina at Chapel Hill.
Surprisingly, this doesn't shorten someone's lifespan or give them a bad prognosis, said Dr. William O'Neill, a cardiologist and executive dean of clinical affairs at the University of Miami's Miller School of Medicine.
"I've done 10 or 15 in a single patient over a period of time," and they still live long lives as long as they don't have a heart attack and suffer damage, he said.
Clinton has not had a heart attack and has done everything right since his bypass — eating well, exercising, keeping his blood pressure and cholesterol in check, said his cardiologist, Dr. Allan Schwartz at New York Presbyterian Hospital.
"This was not a result of his lifestyle or his diet," Schwartz said at a news conference Thursday night. Since the bypass, "he has really toed the line."
And what good does that do, you may ask?
It can keep heart disease from getting worse and fresh blockages forming in new places, said Dr. Spencer King, a cardiologist at St. Joseph's Heart and Vascular Institute in Atlanta and past president of the American College of Cardiology.
Dr. Clyde Yancy, a cardiologist at Baylor University Medical Center in Dallas and president of the American Heart Association, agreed.
"This kind of disease is progressive. It's not a one-time event so it really points out the need for constant surveillance," he said.
About 1 million artery-opening angioplasty procedures are done each year in the United States. Nearly 1 in 5 patients who have one have previously had a bypass operation, said Dr. Ralph Brindis, a cardiologist at California-based Kaiser Permanente health plan and incoming president of the cardiology college.
"On average, a bypass operation lasts 10 years," Brindis said. "He's a little early for having a problem, but not that early."
Clinton also in the past has partly blamed his heart problems on genetics. There is a history of heart disease in his mother's family. He also has admitted being careless about his diet, has had high blood pressure and before his bypass, had stopped taking a cholesterol-lowering drug he'd been prescribed.
Schwartz emphasized how much of that had changed. Clinton's "numbers" were all good, he said. But heart disease "is a chronic condition. We don't have a cure for this condition, but we have excellent treatments."