Evaluation of Analytical Performances and Comparison of 3 NT-proBNP Assays for Diagnosing Heart Failure

Context.— The N-terminal prohormone of the brain natriuretic peptide (NT-proBNP) is a major diagnostic biomarker for heart failure. Objective.— To compare the analytical and clinical performance of 3 NT-proBNP immunoassays: the Atellica IM NT-proBNP assay (Siemens Healthcare Diagnostics), the Alere NT-proBNP assay (Abbott Laboratories), and the Elecsys proBNP II assay (Roche Diagnostics). Design.— For the Atellica IM NT-proBNP assay, analytical performance, including precision, linearity, and carryover, was fully evaluated. Method comparisons among the 3 assays were performed using the Passing-Bablok regression and the κ agreement test. To evaluate the clinical performance of the assays, 160 patient samples were used from patients with (n = 81) or without (n = 79) heart failure. Results.— The analytical performance of the Atellica IM NT-proBNP assay was acceptable according to the manufacturer's claims. The Atellica IM NT-proBNP assay showed a positive bias compared with the Elecsys proBNP II assay. The Cohen κ values among the 3 assays were satisfactory (>0.80) and comparable. There were no significant differences in areas under the curve. However, for the diagnosis of heart failure, the Elecsys proBNP II showed a higher specificity and positive likelihood ratio than the other assays. Conclusions.— All 3 NT-proBNP assays showed acceptable concordance, and their clinical performance was comparable. However, the Elecsys proBNP II might be a more discriminating NT-proBNP assay to diagnose heart failure.