Ghodsi S, Mohebi M, Sadre-Bafghi SA, et al. - In this retrospective cohort study, the potential prognostic utility of calculated apo lipoprotein-B (Apo-B) was examined in a cohort of ST-segment elevation myocardial infarction (STEMI) patients receiving primary percutaneous coronary intervention (PCI). Participants were 2,259 patients with a diagnosis of acute STEMI who had primary PCI. A valid equation based on initial lipid measurements was applied to determine Apo-B. High Apo-B was characterized as a level of 65 or higher. Major adverse cardiovascular events (MACE) was set as the primary endpoint. Following a median follow up of 15 (6.2) months, a connection of high Apo-B with MACE was found and the odds ratio (95% CI) was estimated to be 3.02 (1.07–8.47). For prediction of MACE related to left ventricle ejection fraction and smoking, the estimated odds ratios were 0.97 and 1.07, respectively. Seemingly, calculated Apo-B affords a simple instrument that is applicable for cardiovascular events prediction in patients with STEMI and was found superior to both non-high density lipoprotein cholesterol and low-density lipoprotein.