OBJECTIVES: The objective of this study is to investigate the economic impact per patient using NT-proBNP test to guide the diagnostic assessment and management of dyspneic patients in the Emergency Department in Brazil and Mexico. METHODS: A cost tool was developed based on a decision tree from Siebert study.  It was evaluated the standard clinical assessment (strategy 1) with assessment guided by NT-proBNP (strategy 2), from a payer’s perspective. The direct medical costs were based on the DATASUS (Departamento de Informática do Sistema Único de Saúde – Brazil) and IMSS (Instituto Mexicano del Seguro Social – Mexico) databases converted to 2015 US dollars (USD). The time horizon was 60 days. Additionally, the sensitivity analysis was performed with a variation of 10%. RESULTS: Based on Siebert study, the optimal use of NT-pro-BNP strategy reduces the use of echocardiography from 25% to 10.5% and the average of hospitalization length from 4.41 days to 3.88 days. Therefore, according to our cost tool for Brazil, in the base case scenario, the savings per patient is $218.15, after applying the sensitivity analysis in the best case scenario the savings achieved is $385.23, and in the worst case is $51.07. A similar result could be achieved in Mexico, in the base case scenario the savings per patient is $218.96, while with the sensitivity analysis the savings reached $388.55 for the best case scenario, and $49,37 for the worst case. CONCLUSIONS: The optimal use of NT-proBNP test could improve the management of patients with acute Heart Failure according to our analysis. Moreover, it demonstrated incremental value in diagnosis which may result in improved therapeutic decisions and savings for both countries.