Part 1 (POC Precision):

Objective :

Demonstrate that the Minicare BNP (im)precision in hands of the user is within the expected range of the Minicare BNP (im)precision. Part 2 (sample comparison)

Primary objective :

Compare Minicare BNP values from capillary whole blood from finger stick with EDTA whole blood from venous puncture.

Secondary objective :

Compare Minicare BNP values from EDTA whole blood and plasma with Li- Heparin whole blood and plasma from venous puncture.

Study Design Part 1 (POC precision) Two levels of BNP control samples (Thermofisher) will be tested during 5 days, with 5 replicates per day by three different users to assess precision of the Minicare BNP. The two different levels need to be tested on the same analyzer by the same user. For this study, six analyzers are made available, meaning that each user will test 2 analyzers. In parallel this testing will be done at Philips to establish the expected POC (im)precision. The two (im)precision values will be compared to each other. The precision study will also be used as a proficiency study that is normally requested prior to starting enrolment. Study Design Part 2 (sample comparison)

Part 2 (Sample comparison):

This study will be a prospective European single site study with at least 100 patient samples, taken from patients presenting at the cardiology ward and coronary care unit with suspected/ diagnosed heart failure (HF) or other cardiac diseases and thus suspected elevated BNP values. The blood sample will be collected near the patient by a trained healthcare professional of the study site.

When testing capillary whole blood, the blood will be collected by a finger stick according to the local SOP's of the study site. Directly (within 1 minute) after finger stick, the blood will be transferred with capillary transfer devices, one without ant-coagulant and one containing EDTA as anti-coagulant, to the BNP cartridge that is positioned in the Minicare I-20 analyzer. Testing will be done near the bedside of the patient. Two venous whole blood tubes will be collected; one containing Li-Heparin and the other containing EDTA as anti-coagulant. The venous whole blood will be collected in the specific tubes by a venous puncture according to the local SOP's of the study site. The EDTA venous whole blood will be transferred to the Minicare BNP by using a pipet and a transfer device. The Li-Heparin and EDTA venous whole blood sample should be tested within 2 hours (keep at room temperature) after the blood is taken (preferably as soon as possible after blood taking). Li-Heparin and EDTA venous whole blood can be tested at the ward by a trained healthcare professional or in the lab by a trained lab technician. The Li-Heparin and EDTA whole blood sample will be transferred to the lab and centrifuged and tested within 2 hours after the blood is taken. The Li-Heparin and EDTA plasma should be tested within 2 hours (keep at room temperature) after the blood is taken (preferably as soon as possible after blood taking). Li- Heparin and EDTA plasma samples might be tested in the lab, dependent on local routine.

All patient samples will be tested in singleton. The time that the blood is taken and tested will be recorded for each sample. Study will continue until at least 100 patient samples covering the predefined concentration range have valid measurements. Due to experience from previous sample comparison studies (Lab2Go) the site expects the necessity to test up to 200 patients to find 100 patients within the required BNP ranges. The Minicare BNP test results will not be used as part of the patient diagnosis but only for sample comparison purposes. Testing for both Part 1 and Part 2 will be done according to the Clinical Brochure for Minicare BNP.

Inclusion criteria:

• 18 years or older
• patients with suspected/ diagnosed heart failure (HF)
• signed informed consent form

Exclusion criteria:

• Patients younger than 18 years
• Patients requiring emergency treatment, those with cognitive impairment or inability to understand study information, and those unwilling or unable to provide written consent
• Patients already participated in this study
• Pregnant or breastfeeding women
• Patients with known Hepatitis B or C or HIV infection

Patient samples from eligible patients with BNP requests, available at the test site

Data outcome of study may be included in publication