Sample Comparison The objective of this study is to compare the Philips Minicare BNP test with the Centaur BNP test. BNP level measured in human blood samples (EDTA venous whole blood and/or EDTA plasma) will be assessed. Matrix Comparison To compare BNP measurements obtained using Minicare System for EDTA whole blood and EDTA plasma samples.Prior to the study start, a proficiency study will be performed on the Minicare BNP, Architect and I-STAT BNP assay to be sure that devices are performing according to expectations. Approximately 100 EDTA patient whole blood samples covering the entire measuring range of Minicare BNP from LOQ until end of measuring range (expected to be approximately 5000 ng/L) (Ref 7) will be tested (according to CLSI EP09A3 (Ref 5)) at a central laboratory using the Minicare BNP, Alere BNP, I-STAT BNP system. The outcome of the site routine assay (Centaur BNP systems) will be used to evaluate if the blood samples cover the entire distribution range of the assay. If necessary, up to 20% of the samples may be spiked so that the entire range of the assay is covered. The central laboratory will identify the blood tubes with a BNP request. Approximately 1000 μl EDTA whole blood will be available (left over material) for testing on the non-routine devices (i.e., Minicare BNP, Alere BNP, and I-STAT BNP). Testing for the Alere BNP, I-STAT BNP, and Centaur BNP systems will be performed according to the respective IFU's (Ref 1, 2, 3, 4). For the Minicare BNP system, test will be performed according to a DRAFT IFU or a similar document describing the sample treatment and handling for the Minicare BNP system. Alere BNP, I-STAT BNP and Minicare BNP samples should be tested within 6 hours after collection and Centaur BNP samples within 8h of collection. Although different stability claims for BNP, it is highly recommended to perform all measurements on all systems within 2 hours. For Alere BNP, I-STAT BNP, Centaur BNP analysis will be performed using a single blood sample for each patient. Alere BNP and I-STAT will use EDTA whole blood samples as sample type Centaur BNP will be tested on EDTA plasma samples. For the Minicare BNP, both EDTA whole blood and EDTA plasma will be tested for each patient. For the Minicare BNP system the whole blood samples will be tested using a pipette and the same sample will be tested using the SmearSafe Blood Dispenser (transfer device) to investigate a reliable use of such transfer device.