Los Angeles, CA—The outcomes of coronary artery bypass graft (CABG) surgery are superior to those of percutaneous coronary intervention (PCI) in patients with diabetes and multivessel coronary artery disease (CAD). The better outcomes with CABG were achieved with a small increase in costs over 5 years compared with PCI, making CABG highly cost-effective in this population.
These were the findings from a National Heart, Lung, and Blood Institute–supported study in which 1900 patients with diabetes and multivessel CAD were randomized to CABG or to PCI with deployment of a drug-eluting stent. Valentin Fuster, MD, PhD, Director of Mount Sinai Heart Institute, New York City, and lead investigator of the study, presented the results at the 2012 American Heart Association meeting.
“The results are clear; I think they are going to change practice,” Dr Fuster said.
The study, which enrolled patients with multivessel disease, but not of the left main coronary artery, was conducted at 140 international centers. All study participants received standard care to control blood glucose (target hemoglobin A1c, <7.0%), low-density lipoprotein cholesterol (target, <70 mg/dL), and blood pressure (target, <130/80 mm Hg).
After a mean follow-up of 4.37 years, the combined rate of death, myocardial infarction (MI), and stroke was 18.7% in the CABG group and 26.6% in the PCI group, a relative risk reduction of 29%. The rate of all-cause mortality over the 5 years was 10.9% in the CABG group versus 16.3% in the PCI group; the rate of MI was also lower in the CABG group versus the PCI group (6.0% vs 13.9%, respectively).
As with other trials comparing CABG and PCI, the rate of stroke was higher among CABG recipients at 5.2% compared with 2.4% in the stented group. Cardiovascular deaths were less frequent with CABG than with PCI (55 vs 74, respectively) as was the number of repeat vascularizations at 1 year (42 vs 117, respectively).
“CABG surgery is the preferred method of revascularization for patients with diabetes and multivessel CAD,” concluded Dr Fuster.
Approximately 40% of eligible patients who were screened for the study did not consent to randomization, he noted, because they opted for stenting.
The study was published simultaneously online (Farkouh ME, et al. N Engl J Med. 2012;367:2375-2384). In an accompanied editorial, Mark A. Hlatky, MD, Professor of Health Research and Policy and Professor of Cardiovascular Medicine at Stanford University wrote, “Mortality has been consistently reduced by CABG, as compared with PCI, in more than 4000 patients with diabetes who have been evaluated in 13 clinical trials. The controversy should finally be settled.”
The results of the study do not necessarily apply to other patient populations, said some interventional cardiologists. One is Alice K. Jacobs, MD, Director of the Cardiac Catheterization Laboratory and Interventional Cardiology, Boston Medical Center, and Professor of Medicine, Boston University School of Medicine, who said that CABG may be more beneficial than PCI in patients with diabetes, because CAD tends to be more diffuse in this group, as opposed to focal.
Cost-Effectiveness Analysis
The cost-effectiveness analysis demonstrated that the benefits of CABG in this study “provides not only better long-term clinical outcomes than PCI, but these benefits are achieved at an overall cost that represents an attractive use of societal health care resources,” said Elizabeth A. Magnuson, ScD, Director of Health Economics and Technology Assessment, University of Missouri-Kansas City at Saint Luke’s Mid America Heart Institute, Kansas City, MO.
Initial costs were higher with CABG, at $34,467 for the index hospitalization versus $25,845 for PCI. Cumulative costs narrowed between the 2 groups over the course of the follow-up. At 5 years, CABG increased the total cost per patient by $3641 compared with PCI. This additional cost resulted in a cost per quality-adjusted life-year (QALY) gained of $116,699 at 5 years, making it an attractive use of societal healthcare resources.
However, over a lifetime, patients such as those in the trial who undergo CABG rather than PCI could expect to live an average of 1.266 years longer, lowering the QALY to just $8132, Ms Magnuson said.