SYNTAX Trial: Cardiac Stents Inferior to Bypass Surgery in Some Patients
More than 1.3 million Americans each year undergo angioplasty procedures, which include the placement of a stent, or a metal mesh tube that prevents restenosis (blockage). A certain type of stent, called a drug-eluting stent (or DES stent) has been compared to coronary artery bypass grafting (CABG) in persons with advanced heart disease and found to be inferior after 3 years.
Improved Outcomes Seen 3 Years After CABG versus DES
First-year results from the SYNTAX (Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery) trial, a large randomized clinical trial which compared DES and CABG in 1,800 patients with severe coronary artery disease (CAD) were published last year in the New England Journal of Medicine. Yesterday, 3-year results were released at the European Association of Cardio-Thoracic Surgery annual meeting in Geneva, Switzerland.
Patients were categorized by severity of disease. Those with “mild” disease typically had a single blocked artery. “Moderate” or “severe” disease was defined as blockage in either the left main artery, which is the primary artery that supplies blood to the heart, plus blockage in one of the other three heart arteries or blockage of all three arteries, called three-vessel disease.
The three-year results confirm what had been seen at one year: patients with complex coronary artery disease had fewer heart attacks and less need for further intervention procedures with CABG surgery than with the placement of a drug-eluting stent after angioplasty. Patients receiving DES had more “bad outcome endpoints”, including 28% greater risk for stroke or myocardial infarction, 48% more likely to need for repeat revascularization and 22% more likely to die.
The researchers conclude that while DES may still be an appropriate option for selected individuals, in general, people who have severe enough coronary artery disease that requires surgical intervention over standard medical therapy, CABG is the preferred treatment option for improved survival.
Comparatively, about 448,000 people in the US undergo coronary artery bypass grafting surgery each year according to the National Center for Health Statistics, while 1.3 million have angioplasty procedures. The researchers feel that perhaps 5,000 or more deaths annually may be avoided if some stent patients were to have undergone CABG instead.
"Coronary bypass treats most of the current and future blockages of a vessel. Stenting treats a single lesion," said Dr. Richard Guyton, chief of cardiothoracic surgery at the Emory University School of Medicine. "If there is one severe lesion [blockage] and five emerging lesions, stenting treats the existing lesion and the emerging ones are still there. Because bypass replaces a much longer section of artery, it takes care of the emerging lesions as well.”
However, as with most medical treatments, options should be thoroughly discussed with your doctor before making decisions. SYNTAX investigators have developed a scoring system that will help doctors better determine which individuals with severe CAD might do better with stenting over CABG.
Morice, MC "Left main press conference" EuroPCR (European Association of Percutaneous Cardiovascular Interventions) 2010.
Serruys P, Morice MC, Kappetein P, et al. Percutaneous coronary intervention versus coronary-artery bypass grafting for severe coronary artery disease. N Engl J Med 2009; 360:961-972.