Background Data reporting long-term outcomes of coronary stents implantation versus coronary-artery bypass grafting (CABG) for nonbifurcation lesion of unprotected left main coronary artery (LMCA) disease are limited. We evaluate long-term clinical outcomes after coronary stents implantation versus CABG for ostial and shaft lesion of unprotected LMCA disease. Method A total of 1083 consecutive patients with ostial and/or shaft of unprotected LMCA stenosis who received coronary stenting (n=557) or underwent CABG (n=526) were examined. The 5-year adverse outcomes (death; a composite outcome of death, Q-wave myocardial infarction [MI], or stroke; and target-vessel revascularization [TVR]) were compared with the use of univariate and multivariable Cox proportional hazards regression analysis. Results During follow-up of median 5 years, after adjustment of baseline covariates, the risk of death (hazard ratio [HR], 0.982, 95% confidence interval [CI], 0.773-1.248, p=0.885), and the composite of death, Q-wave MI, or stroke (HR, 0.959, 95% CI, 0.757-1.214, p=0.726) were not significantly different for patients undergoing stenting versus CABG. However, the adjusted risk of TVR was significantly higher in the stenting group than in the CABG group (HR, 3.694, 95% CI, 2.224-6.136, p<0.001) (Table). Similar results were obtained in comparisons of DES or BMS with concurrent CABG Conclusion During 5-year follow-up, stenting showed similar rates of mortality and of the composite of death, Q-wave MI, or stroke, but higher rates of TVR as compared with CABG for patients with unprotected ostial and shaft LMCA lesions.