The aim of the study was to assess the role of plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration as a predictor of patent ductus arteriosus (PDA) in very low birth weight infants beyond the first week of life. This was a prospective observational study; newborns with a birth weight < 1500 g were eligible for enrolment. Enrolled infants were screened by echocardiography on day seven of life for the presence of a PDA. This was paired with a blood sample for NT-proBNP level. Echocardiography and NT-proBNP levels were repeated at weekly intervals. The primary outcome was correlation between PDA and NT-proBNP level and between measurements of PDA significance and NT-proBNP. Sixty-nine neonates were enrolled following parental consent. The mean birth weight was 1119 ± 257 g and mean gestational age was 28.6 ± 2.6 weeks. Median NT-proBNP level on day seven was 11469 ng/l in infants with a PDA vs. 898 ng/l in infants without a PDA (p < 0.0001). There was a statistically significant correlation between PDA diameter and NT-proBNP level on day seven, day 14 and day 21.
Conclusion: NT-proBNP concentration is significantly increased in infants with a PDA and correlates well with PDA diameter in the first three weeks of life.