The MAIN-COMPARE (Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty Versus Surgical Revascularization) registry holds data on consecutive patients from 12 major cardiac centers in Korea that performed PCI or CABG for unprotected left main coronary artery disease (defined as stenosis of more than 50%). From this registry， 2240 patients with unprotected LMCA disease were evaluated who received coronary stents (n = 1，102; 318 with bare-metal stents and 784 with drug-eluting stents) or underwent CABG (n = 1，138) between 2000 and 2006 and for whom complete follow-up data were available for at least 3 to 9 years (median 5.2 years). Complete follow-up for major clinical events at 5 years was obtained in 97.9% of the overall cohort (98.1% for the PCI group and 97.6% for the CABG group).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 and presented by Dr Seung-Jung Park， Seoul， South Korea in the morning’s TCTAP at CIT， Angioplasty Summit.
　　After adjustment for differences in baseline risk factors with the inverse probability of treatment weighting， the 5-year risk of death (hazard ratio [HR]: 1.13; 95% confidence interval [CI]: 0.88 to 1.44， p = 0.35) and the combined risk of death， Q-wave MI， or stroke (HR: 1.07; 95% CI: 0.84 to 1.37， p = 0.59) were not significantly different for patients undergoing stenting versus CABG. The risk of TVR was significantly higher in the stenting group than in the CABG group (HR: 5.11; 95% CI: 3.52 to 7.42， p < 0.001). Similar results were obtained in comparisons of bare-metal stent with concurrent CABG and of drug-eluting stent with concurrent CABG， although some late catch-up in TVR may occur in PCI with DES. In further analysis with propensity-score matching， overall findings were consistent.
　　Several clinical (old age， concomitant peripheral disease， chronic renal failure， insulin dependent diabetes mellitus， low EF) and angiographic characteristics (LM with 3 vessel disease， LM bifurcation lesion) were identified as important predictors for long-term adverse outcomes after stenting in patients with unprotected LMCA disease. Taking these factors into consideration may be helpful to guide optimal treatment strategies for these “high-risk” patients.