Introduction and objectives. Knowledge of operative risk to predict the likely complications and presented objectively inform the patient and family risks of the procedure. Risk four scales were compared to predict morbidity and hospital mortality in patients undergoing coronary artery bypass grafting in CIMEQ. Methods. An analytical, longitudinal and retrospective study. The logistic EuroSCORE and Parsonnet, ACEF and the MCRS scales were used. The statistical tests used were the ROC curves, the method of Hosmer-Lemeshow X2 and logistic regression tests. Results. To predict the ACEF scale mortality had an area under the curve of 0.87 (p 60 years, p = 0.013, LVEF 60 years, p <0.001 and p = 0.003 congestive HF with MACE. Conclusions. The logistic EuroSCORE and ACEF scales behave as probability models useful both for determining the risk of hospital mortality for MACE.