A highly anticipated new study has called into question the long-term effectiveness of stents in the treatment of stable coronary artery disease. Researchers have determined that the use of drug therapy (including blood-pressure and cholesterol drugs) is just as effective in preventing heart attacks or death when compared to a combination of drug therapy and stent implantation. The study results were shared this week at the American College of CardiologyÃ¢â‚¬â„¢s (ACC) annual Scientific Session and will be published next month in the New England Journal of Medicine (NEJM).
The Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation (COURAGE) study included 2,287 angina (acute chest pain due to poor blood flow) patients with at least a 70 percent artery blockage in the U.S. and Canada and assigned each patient into one of two study arms: percutaneous coronary interventions (PCI) and optimal medical therapy (OMT) together or OMT alone. Researchers, led by cardiologist Dr. William Boden of Buffalo General Hospital in New York, followed patients for two-and-a-half to seven years, and results of the study showed a similar rate of death, heart attack, or stroke. Ã¢â‚¬Å“As an initial management strategy in patients with stable coronary artery disease,Ã¢â‚¬Â the authors concluded, Ã¢â‚¬Å“PCI did not reduce the risk of death, myocardial infarction, or other major cardiovascular events when added to optimal medical therapy.Ã¢â‚¬Â
Ã¢â‚¬Å“Conventional wisdom would indicate that PCI and OMT together would be superior to OMT alone,Ã¢â‚¬Â said Dr. Boden. Ã¢â‚¬Å“Indeed, that was our initial hypothesis. But results of the COURAGE trial demonstrate that two treatments are not always better than one. These findings, along with data from recent studies of more than 5,000 patients combined, show that PCI has no impact on reducing major cardiovascular events.Ã¢â‚¬Â
The results of the COURAGE study may have a dramatic effect on the way doctors treat their heart patients. Stenting, especially when using drug-coated devices, is a costly procedure and comes with a variety of other medical dangers, including an increased risk of blood clotting that may lead to heart attacks or strokes. Although the COURAGE study utilized only bare-metal stents, previous studies have already found that the drug-coated stents offer little added benefit when compared to the older and cheaper bare-metal variety. (Bare-metal stents have been shown to be ineffective over time, as many bare-metal-stent patients suffer from re-clogging of their arteries.) In light of the new findings, researchers hope that doctors will more closely follow the established medical guidelines, which call for aggressive drug therapy as the first option.
Ã¢â‚¬Å“During the past 30 years,Ã¢â‚¬Â the authors write, Ã¢â‚¬Å“the use of percutaneous coronary intervention (PCI) has become common in the initial management strategy for patients with stable coronary artery disease in North America, even though treatment guidelines advocate an initial approach with intensive medical therapy, a reduction of risk factors, and lifestyle intervention (known as optimal medical therapy). In 2004, more than 1 million coronary stent procedures were performed in the United States, and recent registry data indicate that approximately 85 percent of all PCI procedures are undertaken electively in patients with stable coronary artery disease.Ã¢â‚¬Â
Although they agree that PCI procedures are valuable in patients with acute coronary symptoms, they contend that a Ã¢â‚¬Å“similar benefit has not been shown in patients with stable coronary artery disease.Ã¢â‚¬Â While PCI does improve blood flow, reduce the onset of angina, and assist with breathing in the short term, the Ã¢â‚¬Å“long-term prognostic effect remains uncertain.Ã¢â‚¬Â
In an accompanying editorial in the NEJM, Drs. Judith Hochman and Gabriel Steg wrote: Ã¢â‚¬Å“The COURAGE trial should lead to changes in the treatment of patients with stable coronary artery disease, with expected substantial health care savings. PCI has an established place in treating angina but is not superior to intensive medical therapy to prevent myocardial infarction and death in symptomatic or asymptomatic patients such as those in this study.Ã¢â‚¬Â
The news was not good for Boston Scientific and Johnson & Johnson, the two biggest stent manufacturers in the $5 billion a year industry, since the large majority of current stent patients do not suffer from acute symptoms. In effect, the research shows that stents are being significantly overused, at great cost (and indeed, risk) to the patient.