The purpose of this study was to investigate the predictor of long-term outcomes in patients after stent implantation for unprotected left main coronary artery (LMCA) disease. Coronary stenting has recently been advocated as an alternative procedure for LMCA disease. Information on the predictors of long-term outcomes in patients after stent implantation for unprotected LMCA disease is not clear. Seventy six patients (51 men and 25 women, age 68 +/- 10 years) with medically refractory angina received coronary stenting for unprotected LMCA disease. During a follow-up period of 40 +/- 26 months, 7 patients (9%) died because of cardiovascular disease in 5 (7%) and noncardiovascular disease in 2 (3%). In the other 69 patients, 19 patients (25%) needed repeated percutaneous coronary intervention (PCI) and/or coronary artery bypass grafting (CABG). In a univariate analysis, only female sex was related to the repeated PCI and/or CABG (P = 0.04). A history of cerebral vascular attack (CVA) (P = 0.005), anemia (P = 0.03) and lower left ventricular ejection fraction (LVEF) (P = 0.008) were related to the cardiovascular mortality. A history of myocardial infarction (P = 0.03), a history of CVA (P = 0.02), anemia (P = 0.02), and lower LVEF (P = 0.002) were related to the total mortality. In a multivariate analysis, female sex (P = 0.007; odds ratio 5.29, 95% confidence interval [CI] 1.57-17.80) and young age (P = 0.025; odds ratio 3.92, 95% CI 1.19-12.98) could predict the repeated PCI and/or CABG. Only a history of CVA could predict the cardiovascular mortality (P = 0.027; odds ratio 34.18, 95% CI 1.49-783) and only lower LVEF could predict the total mortality (P = 0.027; odds ratio 13.26, 95% CI 1.34-131). Female sex and young age could predict the repeated PCI and/or CABG in patients after stent implantation for unprotected LMCA disease. Furthermore, a history of CVA could predict the cardiovascular mortality and lower LVEF could predict the total mortality.