Objectives: To evaluate the cost-effectiveness of alternative approaches to revascularization for patients with three-vessel or left main coronary artery disease (CAD). Background: Previous studies have demonstrated that, despite higher initial costs, long-term costs with bypass surgery (CABG) in multivessel CAD are similar to those for percutaneous coronary intervention (PCI). The impact of drug-eluting stents (DES) on these results is unknown. Methods: The SYNTAX trial randomized 1,800 patients with left main or three-vessel CAD to either CABG (n = 897) or PCI using paclitaxel-eluting stents (n = 903). Resource utilization data were collected prospectively for all patients, and cumulative 1-year costs were assessed from the perspective of the U.S. healthcare system. Results: Total costs for the initial hospitalization were $5,693/patient higher with CABG, whereas follow-up costs were $2,282/patient higher with PCI due mainly to more frequent revascularization procedures and higher outpatient medication costs. Total 1-year costs were thus $3,590/patient higher with CABG, while quality-adjusted life expectancy was slightly higher with PCI. Although PCI was an economically dominant strategy for the overall population, cost-effectiveness varied considerably according to angiographic complexity. For patients with high angiographic complexity (SYNTAX score > 32), total 1-year costs were similar for CABG and PCI, and the incremental cost-effectiveness ratio for CABG was $43,486 per quality-adjusted life-year gained. Conclusions: Among patients with three-vessel or left main CAD, PCI is an economically attractive strategy over the first year for patients with low and moderate angiographic complexity, while CABG is favored among patients with high angiographic complexity. © 2011 Wiley Periodicals, Inc.