| Description: |
Background Natriuretic peptides play an important role in cardiovascular control, stimulating diuresis and vasodilatation and suppressing the renin-angiotensin-aldosterone system. They are also pivotal markers in diagnosis, prognosis and therapy of heart failure (HF), specially BNP and its precursor pro-hormone Nt-proBNP. .Many factors can affect BNP levels in HF patients, potentially reducing its diagnostic accuracy. The main important ones include left ventricular ejection fraction (LVEF), glomerular filtration rate (GFR) and plasma volume (PV). Though the mutual relationship between BNP levels and these drivers is well studied in HF patients, paradoxically little is known about this relationship in physiological conditions in healthy subjects. We tried to elucidate mutual interdependence of BNP, PV, renal function and LVEF in healthy subjects. Methods A total of 200 healthy adult males underwent clinical assessment, measurement of serum levels of BNP, creatinine, uricemia, hemochrome and echocardiography for LVEF assessment. GFR was calculated according to EPI-CKD formula. PV was estimated with both the Hakim formula and the Kaplan formula. The ideal PV (iPV) i.e. the normal PV was calculated using body weight and sex: iPV (in ml) = c × body weight (in kg), where c = 39 in males and 40 in females. Results Mean levels of BP, LVEF, BNP, serum creatinine, GFR, uricemia and PV were all within the normal range. PV1 and PV2 were significantly different from each other and both differed from iPV (Friedman ANOVA; | = 28.4; df = 2; P 0.82 and P |