Heart Drugs Just as Good at Preventing Heart Attacks, Death in Some People, Study Shows
WebMD Health News
Reviewed by Louise Chang, MD
March 26, 2007 (New Orleans) -- Hundreds of thousands of Americans may undergo unnecessary angioplasty and stent procedures to open clogged heart arteries each year, a landmark study suggests.
The long-awaited results show that people with stable coronary artery disease who got common medications to lower blood pressure and cholesterol levels were no more likely to die or to have a heart attack over the next five years than those who also underwent angioplasty with stents.
Of the more than 1.2 million angioplasty procedures performed each year, at least 50% of them are done on an elective basis in people with stable coronary artery disease, says Stephen Nissen, MD, president of the American College of Cardiology (ACC) and head of cardiovascular medicine at The Cleveland Clinic.
In people with coronary artery disease, plaque builds up in the arteries, making it harder for blood to get through, thereby depriving the heart muscle of oxygen. This can lead to chronic chest pain that worsens during exercise and to heart attacks.
During angioplasty, a balloon at the end of a long tube is threaded through an artery in the groin. The doctor shimmies the probe up through the patient's leg and into the arteries of the heart, inflating the tiny balloon at the spot where the vessel has narrowed.
To keep the vessel open, doctors usually add a stent to the end of the balloon catheter. These metal, mesh-like tubes prop open clogged arteries to restore blood flow.
Angioplasty Still Best for Some
The study's results do not apply to people who get stents because they are in the midst of a heart attack or whose chest pain suddenly gets worse, doctors stress. For them, angioplasty is a proven lifesaver.
Additionally, angioplasty is better at relieving the chest pain associated with angina, says researcher William Boden, MD, of Buffalo General Hospital/Kaleida Health in Buffalo, N.Y.
"For an individual patient, angioplasty may still be the best option," he tells WebMD. "But there has been an implication that if you give patients drug therapy rather than angioplasty, you're giving them less than optimal treatment.
"Now we know that if you opt for medicine, you are not putting patients at risk," Boden says.
The study, known as COURAGE, was released at the annual meeting of the American College of Cardiology and simultaneously published online by The New England Journal of Medicine.
Stent Patients as Likely to Die, Have Heart Attack
The researchers studied 2,287 people with stable coronary artery disease who experienced chest pain for about two years, with an average of 10 episodes per week. All had at least a 70% blockage in one or more heart arteries.
All participants were put on optimal drug therapy, which includes nitroglycerin to control chest pain, beta-blockers to control heart rate, ACE inhibitors for lowering blood pressure, and statins to lower cholesterol. Everyone was also urged to exercise more and lose weight and quit smoking, if needed.
Then, about half the participants also underwent angioplasty, usually with stents.
Over the next five years, 19% of those in both groups died or had a heart attack. Similar numbers of people in both groups -- about 12% -- were hospitalized for heart problems.
However, there were some benefits to angioplasty. People who had the procedure were 40% less likely to need another procedure to open up blocked heart arteries. And, particularly in the first two years, they reported better quality of life and less frequent episodes of chest pain.
But over time, some of the differences started to dissipate. By five years later, 74% of people who had angioplasty were angina-free vs. 72% of those who got drugs alone, a difference so small it could be due to chance.
Results Stun Medical Community
Boden notes that COURAGE is "the first properly-sized study to answer the question of whether angioplasty and stents reduce the risk of death and heart attacks in people with stable coronary artery disease."
The results came as a shock to many in the cardiology community -- even to the researchers themselves.
"The study was designed with the hypothesis that the combination of angioplasty and optimal medical therapy would be superior," Boden says. "But the results do not support its benefit in reducing heart attacks and death when used as an initial management strategy."
So why would so many doctors recommend a costly procedure without strong evidence it works?
The average cost of having an angioplasty was $38,000 in 2003, according to the American Heart Association.
Nissen thinks it's because "it seems so intuitively obvious: If you open up a block artery, you'll fix the problem."
American Heart Association President Raymond J. Gibbons, MD, chief of cardiology at the Mayo Clinic, adds that there's a financial incentive for doctors. "People get paid for how many procedures they do," he tells WebMD.
But this study "clearly shows there is no advantage to PCI [percutaneous coronary intervention, or angioplasty] as an initial strategy. It's unnecessary," Gibbons says. "Angioplasty should be reserved for patients [who can't be helped] by medical therapy."
Adds Nissen, "This study will change a lot of thinking. The benefits of angioplasty in people with stable chest pain is very modest, at most. It should be reserved for patients for intolerable symptoms."
But many doctors who perform angioplasties say the procedure's proven benefits in relieving angina, or chest pain, is getting lost in the shuffle.
Donald Baim, MD, chief medical officer of Boston Scientific, a manufacturer of drug-eluting stents, says, "COURAGE is not a catastrophic failure. [It shows that angioplasty plus stents] improves symptoms."
Marty Leon, MD, of Columbia University Medical Center, says, "There are so many deep flaws in the way this study was executed and planned. It was rigged to fail," and it did. "This study should not affect treatment patterns."
Boden says the criticism is unfounded, pointing out that the researchers purposely studied people at medium to high risk of having a heart attack or dying -- "the very people you would expect to benefit most from the procedure."
SOURCES: American College of Cardiology 56th Annual Scientific Session, New Orleans, March 24-27, 2007. Stephen Nissen, MD, ACC president; head of cardiovascular medicine, The Cleveland Clinic. Raymond J. Gibbons, MD, president, American Heart Association; chief of cardiology, Mayo Clinic. Donald Baim, MD, chief medical officer, Boston Scientific. Marty Leon, MD, Columbia University Medical Center, New York. Boden, W. The New England Journal of Medicine, March 28, 2007; vol 356: released online ahead of publication.
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