Diagnostic Accuracy and Rapid Testing of a Novel Acute Heart Failure Biomarker: A Laboratory Evaluation and Comparison with Natriuretic Peptides

Diagnosing acute heart failure in patients presenting with acute dyspnea remains challenging. Current methods, including natriuretic peptide measurement and echocardiography, are time-consuming and not always immediately accessible. A novel biomarker, FILDARIA, may complement natriuretic peptides and enable faster diagnosis. In this study (ClinicalTrials.gov: NCT01024049), samples were collected from 235 patients diagnosed via echocardiography: 89 with non-cardiac dyspnea (NCD), 55 with chronic heart failure (CHF), and 91 with acute heart failure (AHF). Levels of BNP and FILDARIA in each patient were measured using both ELISA and lateral flow assay tests. BNP levels were significantly elevated in AHF and CHF patients compared to NCD patients (905 vs. 58 pg/mL, p < 0.0001; and 447 vs. 58 pg/mL, p < 0.0001, respectively). Similarly, FILDARIA levels were markedly higher in AHF and CHF patients than in NCD patients (1493 vs. 223 ng/mL, p < 0.0001; and 800 vs. 223 ng/mL, p < 0.0001, respectively). The FILDARIA heart failure diagnostic rapid test device accurately identified all 91 AHF patients and correctly excluded 88 of 89 NCD patients, yielding one false positive. Overall diagnostic accuracy was 98.8% (95% CI: 96.0%-99.8%). FILDARIA biomarker demonstrates strong potential as a rapid diagnostic tool for AHF in patients with acute dyspnea. Its high accuracy and compatibility with whole blood could make it an excellent solution for point-of-care testing. Further multicenter research could facilitate wider clinical use and clarify its utility in areas such as prognosis. (ClinicalTrials.gov: NCT01024049).