BACKGROUND: Recently, several reports regarding the protected and/or unprotected left main stenting suggested the possibility of percutaneous intervention for this prohibited area. We intented to evaluate immediate and long-term outcomes after elective stenting of unprotected left main coronary artery in selected patients. METHOD: Forty eight consecutive patients with unprotected left main coronary artery stenosis and normal left ventricular function were treated with stents implantation. The poststent antithrombotic regimen were aspirin, ticlopidine with warfarin in 14 pateints or without warfarin in 34 patients. The stents for left main coronary artery stenosis were Palmaz-Schatz stent in 25, NIR stent in 8, Multi-link stent in 3, Cordis stent in 7, Palmaz stent in 2, Gianturco-Roubin stent II in 2, and Microstent in 1 patient. Intravascular ultrasound was performed in selected patients before predilation and after stenting at late stage of this study. RESULTS: The procedural success rate was 100%. Regardless of anticoagulation, the in hospital complication including stent thrombosis, myocardial infarction, emergency bypass surgery and death did not occur. Six-months follow-up angiography was performed in 31 patients(82%) of 38 eligible patients. The angiographic restenosis occurred in 7 patients(22%) who subsequently underwent elective coronary bypass surgery in 5 patients and rotational atherectomy/balloon angioplasty in 2 patients. The target lesion revascularization rate was 18%. One death(3%) occurred 2 days after elective coronary bypass surgery during follow-up period. CONCLUSION: Stenting of unprotected left main coronary artery stenosis might be a safe and effective alternative to bypass surgery in carefully selected patients with normal left ventricular function. However, further clinical study should be needed for the late outcomes with larger numbers of patients.