Correlation between cord blood, perinatal BNP values and echocardiographic parameters in healthy Italian newborns

We evaluated the correlation between brain natriuretic peptide (BNP) in umbilical cord blood after normal pregnancy, in blood samples of twenty-nine Italian healthy newborns and paired echocardiographic parameters. Plasma BNP was evaluated in UCB (T0) and in blood on day 3 (T1), 30 (T2) of life. Echocardiographic parameters were recorded at T1 and T2. Median of BNP concentrations in cord blood was 8.6 pg/ml. Median BNP concentrations on T1 was 59.2 pg/ml, on T2 was 8.7 pg/ml. Significantly higher BNP concentrations were reported on T1 than T0 and T2 (p<0.0001), while no significant difference resulted between TO and T2. Plasma BNP at T2 was significantly correlated with mVTI (p=0.006), E wave (p=0.004), LA (p=0.047), LVPW (p=0.004), M (p=0.025). No correlation was found with SF% and E/A. Our results confirm that in healthy and term neonates the cord blood BNP concentrations are low. On T1 BNP values are high with wide ranges because of physiological adjustment to postnatal circulation. When echocardiographic parameters are in normal ranges, BNP concentrations return to low levels on day 30. In healthy newborns left ventricular fitting, LA size and M seem to influence BNP levels rather than left ventricular systolic and diastolic function. (C) 2008 Elsevier Ireland Ltd. All rights reserved.