Coronary revascularization with stenting or balloon angioplasty combined with optimal medical therapy is no more effective in preventing a heart attack, other major cardiovascular events or death in patients with stable heart disease, than optimal medical therapy alone, results of a new study conducted in 50 hospitals in the U.S. and Canada has shown.
The new findings, which are expected to change the way stable heart disease is treated in the future, will be presented March 27 at the American College of Cardiology's 56th-annual scientific session by William E. Boden, M.D., professor of medicine and public health in the University at Buffalo School of Medicine and Biomedical Sciences.
Boden is first author on the study.
Results of the research will be posted on the New England Journal of Medicine's Web site and will be the lead article in the April 12 print issue of the journal.
"The results of this clinical trial are profound and unequivocal," Boden stated. "The study confronts head-on the conventional wisdom that revascularization is the best initial treatment for stable heart disease.
"The good news is, there now are more proven options for doctors and their patients with coronary disease," Boden said. "Instead of immediately undergoing angioplasty with stenting or coronary bypass surgery, for patients who have one, two or three narrowed arteries, there is a third option -- intense medical therapy. It's good for both patients and doctors."
Current treatment guidelines for stable heart disease call for doctors first to try aggressive use of medications to reduce low-density lipoproteins (LDL, the "bad cholesterol"), increase high-density lipoproteins (HDL, the "good cholesterol"), lower blood pressure and prevent clots. The guidelines also call for physicians to advise their patients to stop smoking, change their diets and increase physical activity.
However, when angioplasty was introduced in the 1980s, it quickly became the first choice of many physicians to treat stable heart disease, said Boden, even though it was intended initially to be used in acute heart attacks.
Angioplasty involves threading a slim catheter through a large artery in the groin or arm to the site of the blockage, where a tiny balloon is inflated to flatten the plaque against the vessel wall, and a stent, a tiny wire-mesh structure, is deployed to hold the artery open.
"Studies never were done to prove angioplasty produces better outcomes than standard medical treatment in patients with stable heart disease," Boden said. "Today about 85 percent of all angioplasties in the U.S. are done electively in patients with stable disease."
If results of this trial were translated into clinical practice, it could result in substantial health-care cost savings, Boden said.
The Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation trial, or COURAGE, was conducted between 1999 and 2004. It compared survival and heart attack rates in 2,287 persons with stable heart disease who were randomized to receive either optimal medical therapy (OMT) alone or OMT plus percutaneous coronary intervention (PCI), the term currently used for angioplasty with stenting and arterial bypass surgery.
Participants were followed for a median of 4.6 years. The primary outcomes were death from any cause and non-fatal heart attack.
Results showed that there were 211 such events in the PCI group and 202 events in the medical treatment group. The cumulative primary events rates over the 4.6 years were 19 percent in the PCI group and 18.5 percent in the medical therapy group.
There also were no significant differences between the PCI group and the OMT group when frequency of specific events were analyzed. Death, heart attack and stroke occurred in 20 percent of PCI patients versus 19.5 percent of medical treatment patients.
Hospitalization for acute coronary syndrome occurred in 12.4 percent of PCI patients versus 11.8 percent of OMT patients, and 13.2 percent of PCI patients had heart attacks during the follow-up period versus 12.3 percent of those who received medical treatment alone.
PCI significantly reduced the amount of angina, the chest pain heart patients experience when the heart muscle doesn't receive enough oxygen because of arterial blockages. However, medical-treatment patients also experienced substantial relief from angina, especially during the first year, with further improvement at five years, the study showed.
"In my opinion, this is one of the biggest surprises of the COURAGE trial results," said Boden. "One of the major benefits expected of PCI was substantial relief from chest pain.
"However, two-thirds to three-quarters of medical treatment patients became completely angina-free during the follow-up period, which underscores the benefits of aggressive medical therapy in facilitating symptom improvement. These were unexpectedly positive outcomes."
Robert A. O'Rourke. M.D., from South Texas Veterans Health Care System -- Audie Murphy Campus, San Antonia, Texas; Koon K. Teo, Ph.D., McMaster University Medical Center, Hamilton, Ontario, Canada; and William S. Weintraub, M.D., from Christiana Care Health System, Newark, Del., were trial co-chairs.
The study was sponsored by the U.S. Dept. of Veterans Affairs and the Canadian Institutes of Health Research.