Objective: The evaluation of novel biomarkers for the diagnosis of acute destabilised heart failure (HF). Design: Prospectively conducted study on diagnostic accuracy. Setting: Emergency department of a tertiary care hospital. Patients: 251 consecutive patients presenting to the emergency department with dyspnoea as the chief complaint. Main outcome measures: Index tests were plasma concentrations of 10 biomarkers (BNP, MR-proANP, MR-proADM, copeptin, CT-proET-1, ST2, adiponectin, chromogranin A, proguanylin and prouroguanylin). The reference standard was the diagnosis of acute destabilised HF, which was based on the Framingham score for HF plus echocardiographic evidence of systolic or diastolic dysfunction. Results: Median plasma concentrations of all 10 biomarkers were higher in patients with dyspnoea attributable to acute destabilised HF (n = 137) than in patients with dyspnoea attributable to other reasons (n = 114). Applying receiver operating characteristic curve (ROC) analyses, areas under the curve (AUCs) for BNP (0.92) and MR-proANP (0.88) were significantly higher than the AUCs of the other eight biomarkers (MR-proADM, 0.75; adiponectin, 0.73; CT-proET-1, 0.72; proguanylin, 0.68; ST2, 0.67; prouroguanylin, 0.62; copeptin, 0.62; and chromogranin A, 0.56). In multivariate logistic regression analysis only increased BNP and MR-proANP concentrations remained independent markers for the diagnosis of HF. Both markers alone or in combination added similar diagnostic information besides all clinical information available in the emergency department. Conclusions: The data showed that BNP and MR-proANP were the only independent diagnostic markers of HF. Both markers provided similar diagnostic information and were clinically useful as an aid in the diagnosis of acute destabilised HF in an emergency setting. [ABSTRACT FROM AUTHOR]