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Heart failure (HF) has becoming an increasing clinical and social problem worldwide and despite modern therapy the syndrome still imposes high burden on healthcare systems. In contrast to western countries, the diagnosis of HF in Poland is established later, at more advanced stage of the disease, thus leaving less time for modern therapy and more frequently requiring hospitalisation. As a result, the alarmingly high proportion of patients with HF is treated in hospitals in Poland. According to current guidelines clinical suspicion of HF should be verified based on early assessment of plasma levels of natriuretic peptides. Unfortunately, the key test for early diagnosis, especially in emergency departments and in general practice is not reimbursed and therefore hardly available. The paper provides a short review on the physiology and pathophysiology of natriuretic peptides. Important laboratory issues as well as limitations of their use in specific clinical situations are briefly discussed. Further, we focus on clinical use of natriuretic peptides as an important tool for HF diagnosis, guiding therapy and prognosis. Finally, we put spotlight on the use of natriuretic peptides in prevention of HF and also in ambulatory general practice.

Natriuretic peptides compose the group of neurohormones produced by the myocardium in response to its walls stretching caused by the volume or pressure overload. They restrain the sodium kidney reabsorbtion, thus increasing the diuresis and natriuresis. They also participate in blood pressure, initial load as well as the water-mineral balance regulation. The main representatives of this group are ANP (atrial natriuretic peptide) and BNP (brain netriuretic peptide). With regard to slow dynamics of the serum levels changes, the measurements of BNP play an important role in cardiological diagnotics. Its serum concentration raises in these cardiovascular diseases that are connected with the left ventricle overload. So it can be treated as a specific left ventricle dysfunction marker, whereas its high concentrations correlate with the functional class according to NYHA. It also can be used in risk stratification in patients with the acute coronary syndrome and pulmonary embolism, as well as helping to differentiate the pulmonary and cardiac causes of acute dyspnoea. The serum level of NT-proBNP (N-terminal propeptide of brain natriuretic peptide) is also the independent predictive factor of the recurrence of atrial fibrillation after the restoring the sinus rhythm.

Routine examinations during chemotherapy containing anthracyclines evaluate heart function before treatment and monitor cardiotoxic effects during and after therapy. A number of methods are useful in cardiac assessment, including electrocardiography, radiology techniques (RTG, CT, MRI,PET-CT, PET-MRI), echocardiography, radioisotope imaging techniques (scintigraphy, MUGA,PET), and ultra-structure evaluation in biopsy samples. Nevertheless, there is a continuous need for new methods to predict future damage at the initial stages of cardiac changes. In recent years the therapeutic usefulness of biochemical blood parameters in anthracycline-treated patients has been assessed. The levels of cardiac troponins (cTnI, cTnT), natriuretic peptides (ANP, BNP), and endothelin 1 have been included in the studies. Heart-type fatty acid binding protein (H-FABP) is another promising factor showing cardiomyocytic impairment. However, the clinical use of biochemical parameters in diagnosing anthracycline-related cardiotoxicity is still a controversial issue.

The family of natriuretic peptides consists of the atria natriuretic peptide (ANP), the cerebral natriuretic peptide (BNP), the type C natriuretic peptide (CNP) and the peptide isolated from the dendroaspis snakes' poison (DNP), whose presence in humans has not been confirmed. The physiological function of ANP is in the control of arterial blood pressure by regulation of systemic vascular resistance of blood vessels. BNP is produced as one of the factors in the acute response to inflammatory tissue damage, mainly in coronary vessels. Increased serum concentrations of natriuretic peptides have been found in stress situations, such as trauma or major surgery, systemic hypotension, and in intrinsic myocardial dysfunction. High concentrations of natriuretic peptides were observed in severe sepsis, septic shock and in multiple organ failure, probably due to increased secretion by mediators of the inflammatory process.The highest concentrations of ANP and BNP were found in lethal conditions. On admission to ICU, the measurement of natriuretic peptide concentrations could be very helpful in differentiating the etiology of respiratory failure, and for assessment of the severity of ARDS. Quick tests for measurement of natriuretic peptides, so-called the "point of care testing (POCT)" are fast, easy to perform and, not requiring expensive equipment, are relatively cheap. Therefore, the assessment of natriuretic peptide may be used in scoring a patient's clinical status, for precise diagnosis in doubtful situations, and for determining appropriate treatment.