We thank Dr Achanta for his comments on our study.1 We fully agree that the knowledge of plasma concentrations of cardiac biomarkers such as BNP and MR-proANP can aid the correct diagnosis of heart failure. In response to Dr Achanta’s letter we would like to point out that cardiac natriuretic peptides are useful to rule out heart failure, especially in an emergency setting. Accordingly, cut-off values with a high negative predictive value have to be chosen for this purpose. However, these cut-off values differ depending on the analyte to be …