What keeps PDAs from closing?

Article Outline

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It is well known that prostaglandins are the primary factors in patency of the ductus arteriosus. Indomethacin inhibits the production of prostaglandins and results in the closure of the ductus arteiosus in approximately 70% of pre-term infants who receive it. It is not completely clear what happens to keep the ductus arteriosus from closing in the 30% of preterm infants in whom indomethacin does not work. In a report published in this issue of The Journal, Chorne et al evaluated 446 infants who were treated with indomethacin. In this cohort, 14.7% continued to have a PDA after prophylactic treatment. Four variables were associated with ongoing patency of the ductus arteriosus, including gestational age, antenatal glucocorticoid exposure, race, and respiratory distress. These relationships are unlikely to be due to differences in indomethacin concentrations. Further research is needed to establish potential new mechanisms underlying persistent ductal patency which could lead to new treatments to be used when indomethacin fails.