Abstract: AIM:To study the effect of successful percutaneous coronary intervention (PCI) on the mortality rate in patients with chronic total occlusion (CTO). METHODS: Eightyfour CTO cases (12%) of the 700 patients who underswent elective PCI for stable angina at our hospital from 2005 to 2010 were included in this study. CTO patients were divided into successful chronic total occlusion recanalization group (sCTO) and unsuccessful chronic total occlusion (uCTO) recanalization group and the 2year allcause mortalities were obtained (median: 1.8 years; interquartile range: 1.0 to 24 years) and stratified. Major adverse cardiac events (MACE) included myocardial infarction (MI), urgent revascularization, stroke, or death. RESULTS: A total of 58 (690%) procedures were successful and stents were implanted in 97.0% of the successful procedures (mean: 2.3±0.1) stents per patient, 73% drugeluting). Prior revascularization was more frequent in uCTO patients: PCI (36% vs. 21%; P<0.01). Baseline characteristics were otherwise similar. Intraprocedural complications including coronary dissection were more frequent in unsuccessful cases (30.8% vs. 10.3%; P<0.05) but did not affect inhospital MACE (3% vs. 2%; p=NS). The 2year allcause mortality was 17% for uCTO and 4% for sCTO (P<0.01). Multivariate analysis demonstrated that procedural success was independently predictive of mortality ［hazard ratio (HR): 0.32, 95% confidence interval (CI): 0.18 to 0.58］. CONCLUSION: Successful PCI for CTO patients increases their 2year survival rate. Application of new techniques and technologies to improve the procedural success may improve the prognosis.