A-018 Diagnostic Performance of the Novel Beckman-Coulter NT-proBNP-assay in the Early Diagnosis of Acute Heart Failure

Abstract Background The diagnostic performance of the novel Beckman Coulter N-terminal pro-B-type natriuretic peptide (NT-proBNP) assay in the early diagnosis of acute heart failure (AHF) is unknown. Methods This major unmet clinical need was addressed in a secondary analysis using frozen plasma samples obtained in a prospective diagnostic study, enrolling patients presenting with acute dyspnea to the emergency department (ED). Two independent cardiologists/internists centrally adjudicated the final diagnosis using all individual patient's information. NT-proBNP-Beckman Coulter plasma concentrations were measured blinded and directly compared to NT-proBNP-Elecsys concentrations. Agreement analysis was performed by Bland Altman plot. The primary endpoints were the diagnostic accuracy of both assays using the Area-under-the-Receiver-Operating-Curve and the comparison of the performance for diagnosing AHF using the validated NT-proBNP-Elecsys clinical decision values (450/900/1800ng/L for rule-in). The secondary endpoint included the application of the recently suggested NT-proBNP-Elecsys clinical decision values for obese patients. Results 1400 patients (46% 3women, median age 76 years, BMI 25.9m2/kg, LVEF 53%) had both NT-proBNP measurements on presentation to the ED. Of those 744 (53%) had an adjudicated diagnosis of AHF. The agreement analysis showed overall higher concentrations for the NT-proBNP-Beckman assay. The diagnostic accuracy of both assays was excellent (AUC: 0.915 vs 0.922; P = 0.006, respectively). In the clinical application less patients were ruled-out using the Beckman assay compared to the Elecsys assay (18.7% vs 26.3%) with comparable sensitivities (98.9% vs 98.5%). Regarding rule-in NT-proBNP-Elecsys had a significantly higher specificity (78.8% vs 70.9%) and positive predictive value (83.1% vs 78.7%; both P