OBJECTIVES: The aim of this study was to evaluate clinical outcomes of unprotected left main coronary artery percutaneous coronary intervention (PCI) with new-generation drug-eluting stents in a "real world" population. BACKGROUND: PCI of the unprotected left main coronary artery is currently recommended as an alternative to coronary artery bypass grafting (CABG) in selected patients. METHODS: All consecutive patients with unprotected left main coronary artery stenosis treated by PCI with second-generation drug-eluting stents were analyzed in this international, all-comers, multicenter registry. The results were compared with those from the historical DELTA 1 (Drug Eluting Stent for Left Main Coronary Artery) CABG cohort using propensity score stratification. The primary endpoint was the composite of death, myocardial infarction (MI), or stroke at the median time of follow-up. RESULTS: A total of 3,986 patients were included. The mean age was 69.6 ± 10.9 years, diabetes was present in 30.8%, and 21% of the patients presented with acute MI. The distal left main coronary artery was involved in 84.6% of the lesions. At a median of 501 days (≈17 months) of follow-up, the occurrence of the primary endpoint of death, MI, or cerebrovascular accident was lower in the PCI DELTA 2 group compared with the historical DELTA 1 CABG cohort (10.3% vs. 11.6%; adjusted hazard ratio: 0.73; 95% confidence interval: 0.55 to 0.98; p = 0.03). Of note, an advantage of PCI was observed with respect to cerebrovascular accident (0.8% vs. 2.0%; adjusted hazard ratio: 0.37; 95% confidence interval: 0.16 to 0.86; p = 0.02), while an advantage of CABG was observed with respect to target vessel revascularization (14.2% vs. 2.9%; adjusted hazard ratio: 3.32; 95% confidence interval: 2.12 to 5.18; p <0.0001). CONCLUSIONS: After a median follow-up period of 17 months, PCI with new-generation drug-eluting stents was associated with an overall low rate of the composite endpoint of death, MI, or cerebrovascular accident. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.