Chronic total occlusion intervention of the non-infarct-related artery in acute myocardial infarction patients: the Korean multicenter chronic total occlusion registry

Background The Korean chronic total occlusion (CTO) registry was collected prospectively from 26 cardiovascular centers since May 2007. The aim of this study is to investigate the impact of a successful staged percutaneous coronary intervention (PCI) of CTO lesions in acute myocardial infarction (AMI) patients on clinical outcomes. Patients and methods Among 2813 patients who underwent a staged PCI because of CTO lesions, 422 (15%) patients underwent primary PCI because of AMI. Among 422 patients, successful staged CTO-PCI was performed in 76%. The clinical outcomes were compared between the successful CTO-PCI group (n=321) and the failed CTO-PCI group (n=101). To adjust for potential confounders, a propensity score matching (PSM) analysis was carried out using the logistic regression model. Results After the PSM analysis, two propensity-matched groups (85 pairs, n=170) were generated and the baseline characteristics were balanced. The incidence of total death (P=0.029) and non-ST-segment elevation myocardial infarction (NSTEMI, P=0.043) at 1 year was higher in the failed CTO-PCI group. Multivariate regression showed that successful CTO-PCI was an independent predictor of preventing mortality (hazard ratio, 0.21, P=0.048). In the subgroup analysis, the Kaplan–Meier curve showed that successful CTO-PCI had a lower incidence of total death (log-rank=0.004) and cardiac death (log-rank=0.005) up to 1 year in NSTEMI patients. Cox-proportional analysis showed that successful CTO-PCI was beneficial in patients with NSTEMI, hypertension, and non-left-anterior descending artery lesion for preventing mortality. Conclusion In this study, a staged successful CTO-PCI in AMI patients was associated with improved 1-year survival in the Korean population.