In contrast, MACE occurred more often after DES implantation than after CABG in those with an intermediate or high SYNTAX score.950 At 3 years of follow-up, the mortality rate was greater in subjects with 3-vessel CAD treated with PCI than in those treated with CABG (6.2% versus 2.9%). The differences in MACE between those treated with PCI or CABG increased with an increasing SYNTAX score Although the utility of using a SYNTAX score in everyday clinical practice remains uncertain, it seems reasonable to conclude from SYNTAX and other data that outcomes of patients undergoing PCI or CABG in those with relatively uncomplicated and lesser degrees of CAD are comparable, whereas in those with complex and diffuse CAD, CABG appears to be preferable.949,980 See Online Data Supplements 6 and 7 for additional data comparing CABG with DES. 5.7. Left Main CAD 5.7.1. CABG or PCI Versus Medical Therapy for Left Main CAD CABG confers a survival benefit over medical therapy in patients with left main CAD. Subgroup analyses from RCTs performed 3 decades ago included 91 patients with left main CAD in the Veterans Administration Cooperative Study.961 A meta-analysis of these trials demonstrated a 66% reduction in RR of death with CABG, with the benefit extending to 10 years.412 The CASS Registry381 contained data from 1484 patients with $50% diameter stenosis left main CAD initially treated surgically or nonsurgically. Median survival duration was 13.3 years in the surgical group and 6.6 years in the medical group. 