Diastolic flow velocity of the left pulmonary artery of patent ductus arteriosus in preterm infants

Background: The usefulness of diastolic pulmonary How velocity determined b y echocardiography in the assessment of symptomatic patent ductus arteriosu s (sPDA) in preterm infants has not been confirmed. Methods: Echocardiography was performed daily in infants: ranging from 23 t o 31 gestational weeks of age, and diastolic flow velocity of the left pulm onary artery (DFLPA) was measured. The DFLPA data before indomethacin admin istration for sPDA were compared with data obtained after indomethacin admi nistration. The normal range of DFLPA was also determined from serial measu rements performed in infants who did not develop sPDA during the first 7 da ys: of life. Then, this range was compared with data from infants who did d evelop sPDA during this time. Results: In infants who underwent indomethacin treatment, DFLPA increased w ith the development of sPDA and decreased when the symptoms of sPDA disappe ared. On the basis of results from serial DFLPA measurement, the sensitivit y and specificity of DFLPA for assessing sPDA was found to be 0.82 and 0.83 , respectively. Conclusions: Measurement of DFLPA by echocardiography is a useful method fo r assessing sPDA in preterm infants.