• Interventional Techniques & Devices
• Diabetes Mellitus
• Coronary Artery Disease
• Cardiology Clinical Trials

In the United States alone, ∼700,000 patients undergo multivessel coronary revascularization yearly. Of these, 25% have diabetes [Smith SC et al. Circulation 2002]. Valentin Fuster, MD, PhD, Mount Sinai School of Medicine, New York, New York, USA, presented results from the Comparison of Two Treatments for Multivessel Coronary Artery Disease in Individuals with Diabetes [FREEDOM] trial.

According to Dr. Fuster, the FREEDOM trial was the largest prospective study of revascularization strategy in patients with diabetes and multivessel coronary artery disease (CAD) undergoing intensive medical treatment. Its purpose was to compare mortality and major adverse cardiovascular events in diabetic individuals with multivessel CAD randomized to either coronary artery bypass graft (CABG) surgery or percutaneous coronary intervention (PCI). The primary outcome measure was a composite of death from any cause, nonfatal myocardial infarction (MI), and nonfatal stroke [Farkouh ME et al. N Engl J Med 2012].

FREEDOM was sponsored by the National Heart, Lung, and Blood Institute, and inclusion criteria were a diagnosis of diabetes as defined by the American Diabetes Association guidelines: angiographically confirmed multivessel CAD with severe (>70%) lesions in at least 2 major epicardial vessels, and an indication for revascularization based on symptoms of angina and/or objective evidence of myocardial ischemia. Prior to randomization, all qualifying angiograms were reviewed by a study-related interventionalist and surgeon.

A total of 1900 patients with diabetes and multivessel CAD were enrolled from 2005 through 2010 from 140 international centers, and randomized to undergo either PCI with drug-eluting stents or CABG. Patients were followed for a minimum of 2 years (median among survivors, 3.8 years) and all patients were recommended to be prescribed currently indicated antidiabetic, antihypertensive, and lipid-lowering therapy by their treating physicians [Farkouh ME et al. N Engl J Med 2012].

The mean patient age was 63 years, 29% were women, 83% had three-vessel disease, and mean ejection fraction was 66%. As compared with PCI, the primary outcome was significantly reduced with CABG at 5 years (18.7% vs 26.6%; absolute difference, 7.9 percentage points; 95% CI, 3.3 to 12.5; p=0.005). The benefit of CABG was driven by differences in rates of both MI (p<0.001) and death from any cause (p=0.049). Stroke was more frequent in the CABG group, with 5-year rates of 2.4% in the PCI group and 5.2% in the CABG group (p=0.03). There was no statistical interaction between the benefit of CABG on the primary endpoint and Synergy Between PCI with TAXUS and Cardiac Surgery (SYNTAX) score or any other prespecified subgroup.

Dr. Fuster concluded that, in patients with diabetes and multivessel coronary disease, CABG was of significant benefit compared with PCI and it is the preferred method of revascularization in this setting. He noted that FREEDOM was relatively short-term—7 years, with a minimum of 2 years and a median of 3.8—and long-term follow-up would provide a better understanding of the comparative benefit of CABG, specifically on mortality.

Elizabeth A. Magnuson, MD, University of Missouri-Kansas City, Kansas City, Missouri, USA, presented a cost-effectiveness analysis of the FREEDOM trial. While CABG was associated with higher initial costs (∼$9000) compared with PCI, this cost difference was partially offset by lower costs associated with repeat revascularization and, to a lesser extent, cardiac medications.

At 5 years, CABG improved quality-adjusted life expectancy by ∼0.03 years while increasing total costs by ∼$3600 per patient. Over a lifetime, CABG was associated with 0.66 quality-adjusted life year (QALY) gained and ∼$5400 per patient higher costs yielding an incremental cost-effectiveness ratio of $8132 per QALY gained.

According to Dr. Magnuson, results were robust under various sensitivity analyses regarding the duration of the CABG effect on both survival and costs. Results were also consistent across a wide range of subgroups. Based on these findings, she concluded that CABG provides better long-term clinical outcomes than drug-eluting stent PCI for patients with diabetes and multivessel CAD, and these benefits are achieved at an overall cost that represents an attractive use of societal healthcare resources. The outcomes also provide additional support for existing guidelines that recommend CABG for diabetic patients with multivessel CAD.

• © 2012 MD Conference Express®