FREEDOM was a 5-year superiority trial. Researchers randomly assigned 1,900 patients (mean age, 63 years; 29% women) with diabetes and multivessel CAD to CABG or PCI with a DES at 140 centers throughout the world between 2005 and 2010. Patients were followed for a minimum of 2 years; the median follow-up period of 3.8 years.
Results showed that the primary outcome — a composite of all-cause mortality, nonfatal MI or nonfatal stroke — occurred more frequently in those who underwent PCI vs. CABG. Five-year rates were 26.6% in the PCI group vs. 18.7% in the CABG group (P=.005). MI rates also significantly favored CABG over PCI (6% vs. 13.9%; P<.0001), as did all-cause mortality (16.3% vs. 10.9%; P<.001). Stroke, however, occurred more frequently in the CABG group (5.2% vs. 2.4%; P=.03).
Secondary outcome measures included the rate of a composite of death, MI, stroke and repeat revascularization, and individual rates of these components, at 30 days and 12 months after the procedure. Researchers noted no significant differences after 30 days, but found significantly higher rates of CV and cerebrovascular events in the PCI group compared with the CABG group at 12 months (17% vs.12%; P=.004). This difference was primarily driven by the greater number of repeat revascularization events among PCI patients (13% vs. 5%; P<.0001).
Importantly, according to Fuster, these results were consistent across all prespecified subgroups, including across complexity of disease. Event rates were significantly higher in PCI patients as compared with CABG patients for those with Syntax scores of 22 or lower (23.2% vs. 17.2%), between 23 and 32 (27.2% vs. 17.7%) and 33 or higher (30.6% vs. 22.8%; P=.58 for all).
The results of FREEDOM add to the consistent evidence base supporting CABG as the preferred strategy for patients with diabetes and multivessel coronary disease. However, it will be important to determine whether the relationship between the primary endpoint curves is maintained with longer-term follow-up as the saphenous vein bypass grafts begin to fail, and whether the continued evolution of new DES technology will diminish the advantage of CABG is unclear. But it does appear less likely if the mechanism of the effect of CABG is to protect the myocardium against new disease
The results of FREEDOM add to the consistent evidence base supporting CABG as the preferred strategy for patients with diabetes and multivessel coronary disease. However, it will be important to determine whether the relationship between the primary endpoint curves is maintained with longer-term follow-up as the saphenous vein bypass grafts begin to fail, and whether the continued evolution of new DES technology will diminish the advantage of CABG is unclear. But it does appear less likely if the mechanism of the effect of CABG is to protect the myocardium against new disease