N-terminal pro-B-type natriuretic peptide: a measure of significant patent ductus arteriosus.
BACKGROUND
B-type natriuretic peptide (BNP) is a marker for ventricular dysfunction secreted as a pre-prohormone, pro-B-type natriuretic peptide (proBNP), and cleaved into BNP and a biologically inactive fragment, N-terminal pro-B-type natriuretic peptide (NT-proBNP). Little is known about the clinical usefulness of NT-proBNP in preterm infants.


OBJECTIVE
To evaluate the usefulness of plasma NT-proBNP in diagnosing haemodynamically significant patent ductus arteriosus (hsPDA) in neonates and examine some factors that might affect this.


METHODS
Infants born at <34 weeks' gestational age (GA) and <2 kg birth weight (BW) were prospectively enrolled within 6-12 hours of birth. Plasma NT-proBNP levels were measured on days 1, 3, 5 and 10 with simultaneous echocardiography done to detect hsPDA and assess ventricular function. Significant PDA was diagnosed by large ductal flow with left to right shunt on colour Doppler, measuring >1.6 mm on two-dimensional echocardiography, along with clinical features of PDA.


RESULTS
Forty-nine infants were analysed. Median GA was 30 weeks (range 24-33) and median BW 1220 g (range 550-1950). Eighteen infants with hsPDA had higher day 3 plasma NT-proBNP values (median 32 907 pg/ml; range 11 396-127 155) (p<0.001) than controls (median 3147 pg/ml; range 521-10 343). Infants who developed sepsis had higher day 10 plasma NT-proBNP levels. Area under receiver operator characteristic curve for detection of hsPDA, by day 3 NT-proBNP value, was significant 0.978 (95% CI 0.930 to 1.026). NT-proBNP was predictive of hsPDA (sensitivity 100%; specificity 95%) at a cut-off value of 11 395 pg/ml.


CONCLUSIONS
Plasma NT-proBNP level on day 3 is a good marker for hsPDA in preterm infants. Serial measurements of NT-proBNP may be useful in assessing the clinical course of PDA.
Farombi-Oghuvbu
I
I
Department of Neonatal Paediatrics, Rotunda Hospital, Parnell Street, Dublin 1, Ireland. ibuky@hotmail.com
Matthews
T
T
Mayne
P D
PD
Guerin
H
H
Corcoran
J D
JD
D015415:Biomarkers / Q000097:blood; D004374:Ductus Arteriosus, Patent / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011446:Prospective Studies; D012680:Sensitivity and Specificity
D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain