"What the trial says to me is that intensive medical therapy is remarkably effective at relieving angina as well as preventing heart attacks and death," said Judith S. Hochman, director of cardiovascular clinical research at New York University School of Medicine, who wasn't involved with the study. "Patients should be reassured that the medicines we have now to treat coronary disease are excellent."
But stent proponents say the study provides little new information. The role of stents has long been to relieve symptoms, rather than to decrease rates of deaths or heart attacks over the long-term, said Donald Baim, chief medical officer at Boston Scientific Corp., a leading maker of the devices. The idea that the study would show such a benefit was an "unlikely thesis," he said. Moreover, nearly everyone treated with stents in the 2,300-patient study received a bare-metal device and not the drug-coated version that is much more commonly used today.
"Stents have improved the lives of millions of patients," Dr. Baim added in a statement.
For patients, the most powerful message may be this: If you have stable chest pain or are diagnosed with blockages but have no symptoms, you have time to weigh options and try to reduce your heart-attack risk with drugs and healthier living.
"Medical therapy has gotten a bad rap," said William E. Boden, cardiologist at Buffalo General Hospital, Buffalo, N.Y., and principal investigator of the study, called Courage. "It seems old-fashioned." But the findings show that "if you opt for medical therapy as the initial strategy for treatment, you are not putting [yourself] in harm's way."
The Courage study is the most recent report to give a boost to an aggressive drug strategy in certain cases. In a narrower study last fall, researchers reported that among patients who were stable for at least three days after a heart attack, stent treatment was no better than medication in extending long-term survival or reducing chances of a subsequent heart attack.
Funded by the U.S. Department of Veterans Affairs, the Canadian Institutes of Health Research and several pharmaceutical companies, the study was one of the most rigorous attempts to evaluate long-term performance of stents. The high-tech devices have transformed treatment of heart disease over the past decade as they have grown to a $6 billion global business.
The devices have been proven to save lives and reduce risk of further heart attacks when used to treat patients suffering a heart attack or episodes of unstable chest pain doctors call the acute coronary syndrome. They are also especially effective at providing quick relief of chest pain by propping open arteries and restoring blood flow to the heart's muscle. Some doctors say angioplasty and stents may be the better option for patients whose daily activities are restricted by chronic chest pain.
But researchers say many doctors have extrapolated those results to the broader segment of patients with stable disease, with the implicit promise that undergoing a stent procedure will do more than just cure the pain.
Patients are "fearful, and they kind of assume they're going to live longer if they have a stent put in than if they don't," said Spencer King, a cardiologist at Fuqua Heart Center, Atlanta, and a pioneer in developing stent technology.
Underscoring the impact of the Courage study was the outcry surrounding the release of the data, which is being published in the New England Journal of Medicine. The timing of such releases is closely guarded by medical researchers and journals, and these particular findings were to be presented today at the annual meeting of the American College of Cardiology in New Orleans, where it was among the most anticipated reports on the program.
But Martin Leon, founder and former chairman of the Cardiovascular Research Foundation, New York, and a prominent advocate of stents, mentioned the study at a large audience at a symposium Sunday night, saying that the study was "rigged to fail, and it did." He didn't provide any detail. The college said it considered the comments, reported by The Wall Street Journal on its Web site and Health Blog7, as having betrayed "the confidentiality of the scholarly process and the professional integrity of the scientific community."
Dr. Leon in an interview said the Journal's report was "an exaggerated interpretation" of his remarks. He said he didn't report any data and hadn't any intent to reveal findings ahead of the scheduled presentation.
News of the result contributed to a 6.6% decline in shares of Boston Scientific, which closed at $14.22 in New York Stock Exchange composite trading. Another study favoring a competitor of the company's Taxus drug-coated stent also affected the stock.
For the Courage study, 2,287 patients with significant coronary artery disease, including evidence of blockages and chronic angina symptoms, all were assigned to aggressive medical treatment. They were given such medicines as cholesterol-lowering statins, blood-pressure drugs and aspirin, and urged to quit smoking, eat healthy foods and exercise. Then about half were also assigned to undergo an angioplasty or stent to treat obstructions. They were followed for more than 4½ years. Dr. Boden reported there were 211 deaths and heart attacks among patients who got stents plus medical treatment and 202 among those treated with drugs alone.
While stent patients were more likely to have quick and sustained relief from angina, those getting medical treatment had symptom relief that surprised the researchers. At one year, 58% of medical-therapy patients were free of angina, compared with just 13% when the study began. For stent patients, 66% were angina free after one year, compared to 13% at baseline. The angina-free gap between the two groups narrowed further at three years and was essentially gone after five years.
During the study about one-third of patients initially assigned to medical treatment crossed over because of symptoms and underwent angioplasty and stent procedure, which contributed to the symptom relief reported for drug-alone patients.
How big an impact the study will have on stent procedures is hard to tell. Christopher Cannon, a cardiologist and researcher at Brigham and Women's Hospital, Boston, estimates 10%-15% of patients now getting the devices may be candidates for drug therapy alone. "This should lead to a pullback in some procedures," he said. Others think 25%-40% of current stent patients may be candidates for drug therapy as an initial approach.
Stent proponents say some results of the study -- though not necessarily survival and heart-attack prevention -- may have favored the devices if drug-coated stents were used. The study began well before the new stents were introduced.
Worries about rare but potentially serious blood clots in the drug-coated versions is provoking a shift back to bare metal devices for some patients. The new findings "certainly offer an alternative strategy" for such patients, said Sidney Smith, professor of medicine at University of North Carolina, Chapel Hill and an interventional cardiologist.