Objective: To determine whether N-terminal-pro-brain natriuretic peptide (NT-proBNP) level could be an effective guide for early targeted indomethacin therapy for patent ductus arteriosus (PDA) in preterm infants.

Methods: An interventional study involved preterm infants, born at <33 weeks of gestation, who had plasma NT-proBNP levels obtained at day 2 of life. Indomethacin therapy was given if plasma NT-proBNP level was ≥10,180 pg/mL, the cut-off for predicting hemodynamic significant PDA (hsPDA). Echocardiograms were performed within 6 h at the time of plasma NT-proBNP collection and again at day 7, or whenever clinical hsPDA was suspected. Primary outcomes were the incidence of later hsPDA and unnecessary exposure rate to indomethacin.

Results: Fifty infants were enrolled. On day 2, 19 (38%) infants had plasma NT-proBNP above the cut-off and received indomethacin therapy; none of them developed later hsPDA, while 1 of 31 infants with NT-proBNP below the cut-off level developed clinical hsPDA. Unnecessary exposure to indomethacin occurred in two infants (11%). Overall, no enrolled infants had either reopening of ductus or PDA ligation.

Conclusions: Using NT-proBNP level on day 2 as a guide for early targeted indomethacin therapy reduced later onset of hsPDA and the number of unnecessary exposures to indomethacin.