BACKGROUND: Heart failure, where the heart cannot pump blood effectively, significantly affects patient quality of life and impacts national health-care services. Acute coronary syndrome is a common underlying cause of acute heart failure. Neutrophil gelatinase-binding lipocalin (NGAL) and N-terminal pro B-type natriuretic peptide (NT-proBNP) are biomarkers released during myocardial injury. Thus, the measured levels of these chemicals may be associated with heart failure events in patients with acute coronary syndrome. AIM: The present study determined the serum levels and measured increases in NGAL and NT-proBNP, as well as recorded heart failure events in patients with acute coronary syndrome in Vietnam. METHODS: A descriptive cross-sectional method was used to recruit 58 patients with acute coronary syndrome and assess the degree to which the two markers could predict ejection fraction (EF). RESULTS: The median values of NGAL and NT-proBNP concentrations in the group with EF ≥40% (7.14 ng/mL and 952.00 pg/mL) were significantly lower than those with EF <40% (166.10 ng/mL and 27,498.00 pg/mL). NGAL was used to predict heart failure events at a threshold of 94.86 ng/mL with a sensitivity of 83.3%, a specificity of 90.4%, and an area under the curve (AUC) of 0.83. Similarly, NT-proBNP predicted heart failure events at a threshold of 8660.5 pg/mL with a sensitivity of 83.3%, a specificity of 84.6%, and an AUC of 0.79. CONCLUSIONS: Serum NGAL and NT-proBNP levels can be used as reliable biomarkers for predicting heart failure events in patients with acute coronary syndrome.