THURSDAY, Aug. 16, 2001 (HealthDayNews) -- The combination of aspirin and a powerful clot-blocking drug significantly reduces the risk of new heart problems and heart-related death in patients who undergo invasive vessel-widening procedures, a new study says.
Patients who take clopidogrel plus aspirin before undergoing balloon angioplasty or coronary stenting have a better prognosis, both short-term and long, than those who take aspirin alone, according to the study.
Giving the drug to everyone who needs it could prevent between 50,000 and 100,000 heart attacks, strokes and other heart problems a year in North America, the researchers say. A report on the findings appears in the Aug. 18 issue of The Lancet.
Aspirin therapy prior to such vessel procedures, known as percutaneous coronary intervention (PCI), has long been the standard of care to cut the risk of potentially deadly clotting that can form in the area.
Clopidogrel, which has been dubbed a "super-aspirin," is a so-called antiplatelet drug that prevents these blood cells from clumping together and encouraging clots. It is marketed as Plavix by Bristol-Myers Squibb and Sanofi-Synthelabo, and is often prescribed after vessel-widening procedures. Both companies funded the latest research.
The new study falls out of an earlier report on use of the combination therapy in 12,500 patients with unstable angina, or recurrent chest pain. That work, which involved patients in 28 countries, showed that the treatment prevented more heart attacks, heart-related deaths, and cardiac interventions than aspirin alone.
A team led by Dr. Shamir Mehta, an assistant professor of medicine at McMaster University in Hamilton, Ontario, compared the two treatments in a subset of 2,658 patients with acute coronary syndrome who underwent vessel-widening procedures.
Within that group, 1,313 took Plavix and aspirin for an average of six days leading up to their PCI procedure. After a month-long hiatus from the drug, patients who'd taken Plavix started up again on a somewhat lower dose and continued taking it for an average of eight months.
Patients on the combination treatment were about 25 percent less likely to suffer a heart attack while awaiting PCI, the researchers say. And after PCI, they were about 30 percent less likely than those on aspirin and a dummy pill to have a heart attack, need an urgent vessel procedure or die from a heart-related cause, the researchers say.
And over the long-term, the group that got the combined therapy had a 17 percent lower risk of more heart trouble.
The two-drug therapy was associated with a slightly higher rate of heart-related deaths both within 30 days of the operation and after an average of nine months of follow-up, but the researchers say that increase is trivial. Both groups of patients experienced bleeding, but the addition of Plavix to aspirin didn't seem to increase that risk significantly, the researchers say.
"The bottom line is that patients with unstable angina should be considered for clopidogrel. And it should be started as soon as they come [to the hospital]; it should be considered long-term and certainly at least a year," says Dr. Salim Yusuf, director of cardiology at McMaster and a co-author of the study.
"Irrespective of management style, and irrespective of intention to subject a patient to an intervention, it makes sense to use this" treatment, Yusuf adds.
While aspirin costs pennies a day, a three-month supply of Plavix can run about $260.
Dr. Valentin Fuster, director of the cardiovascular institute at Mount Sinai School of Medicine in New York City and a past president of the American Heart Association, says the latest findings are particularly important for smaller hospitals that lack the resources to perform cardiac interventions.
"In institutions that do not have such procedures, the possibility of using this [therapy] on patients at low and moderate risk" of serious heart trouble buys them time, Fuster says. And if these patients eventually need a PCI, the pre-treatment period with aspirin and Plavix will reduce their risk of problems after the operation.
But not all heart experts are convinced that the double-drug therapy is truly effective in the long-term. Dr. Rodney Stables, a cardiologist at Royal Liverpool University Hospital, notes that the bulk of the benefit is front-loaded into the first month after the vessel operations.
Beyond 30 days, "there is no significant advantage" of Plavix and aspirin over aspirin alone, Stables writes, because the rates of heart attack and heart-related death differ by too narrow a margin to be considered statistically important.
What To Do
Acute coronary syndrome sends more than a million Americans to the emergency room each year.
For more on cardiac interventions, check out Torrance Memorial Medical Center.
To find out your risk of heart attack and stroke, visit the American Heart Association.
