The results of a three-year study showing coronary bypass grafts were often better than drug-eluting stents for patients with severe heart disease may not surprise cardiologists and astute patients who have watched the warnings for stents grow in recent years.
Around 1.3 million Americans each year have angioplasty, which props open a clogged artery with a balloon and often involves a stent — what amounts to a tiny mesh-like device that acts like a permanent scaffold. About half of those patients have severe heart disease that researchers now say might be better treated with bypass surgery. A little fewer than 450,000 Americans currently receive bypass grafts, according to the National Center for Health Statistics.
More advanced drug-eluting stents designed in the past decade, which the study compared, are meant to prevent repeat clogging, but they come with their own set of dangers, as Miller-McMune.com highlighted in April.
Researchers now estimate that possibly hundreds of thousands of Americans should be having bypass surgery rather than stenting, resulting in up to 5,000 additional deaths each year and numerous other complications such as heart attack and stroke.
Results of the ongoing Syntax trial (see the PowerPoint presentation here) were reported Sept. 12 at the European Association of Cardio-thoracic Surgery 2010 Annual Meeting in Geneva, Switzerland. Researchers there reported that after a three-year clinical trial of 1,800 patients, those receiving the industry-leading Taxus drug-eluting stent, made by Boston Scientific, were more likely to suffer a heart attack, stroke or even death.
For patients with mild heart disease, stenting was found equally effective, though previous research such as the Courage trial and Bari2D have supported medical therapy alone for many of those patients.
The results of the Syntax trial weren't entirely shocking. The two-year outcomes, reported at last year's conference, and the one-year results, published in the New England Journal of Medicine in 2009, were all trending that way. But these latest figures will significantly affect medical practice, experts told the Los Angeles Times.
The Syntax trial is associated with the Syntax Score — both funded by Boston Scientific — which helps physicians rate the severity of coronary artery disease.
This growing consensus around which patients benefit most from stents has helped tamp down a decade-long turf war between partisans of interventional cardiology, such as angioplasty and stenting, and those who favor bypass surgery.
For severe heart disease, patients often prefer stents — particularly the drug-eluting kind — because they go home quicker and heal more easily. The procedure, too, is much easier to perform and highly profitable.
Few medical device markets took off as fast as coronary stents. Having experienced huge growth in the 1990s, the stent market peaked at $4 billion in annual sales in 2005. Warnings the devices could cause heart attacks and reports of doctors' over-use led to new guidelines for the most appropriate utilization and a cooling in the industry.
In an interview earlier this year, Dr. Steven Bailey, chief cardiologist at the University of Texas Health Science Center at San Antonio, denied that the medical device industry might have influenced doctors to implant too many stents.
"This is not about industry relationships," Bailey said "Folks are out there trying to come up with the best decision plan for our patients. In many cases and many practices, it may be the lone cardiologists, but increasingly there are a number of cardiologists who are part of that care plan. It's not just the surgeon. And there is certainly a critical review of what the literature is telling us."