Measurement of Elecsys NT-proBNP in serum, K2 EDTA and heparin plasma

Objective: There is controversial evidence on a matrix influence on the measurement of NT-proBNP. Design and methods: We compared results of Elecsys NT-proBNP measurement on serum, K2 EDTA plasma and lithium heparin plasma. Results: Samples collected in K2 EDTA showed a marginally significant underestimation when compared to serum and heparin, whereas no significant difference was observed between serum and heparin plasma. Conclusions: Serum, heparin and K2 EDTA plasma may be suitable for NT-proBNP measurement.