The value of high frequency ultrasound in predicting spontaneous closure of patent ductus arteriosus in ;preterm neonates / 中华医学超声杂志（电子版）

ABSTRACT

Objective To study the value of high frequency ultrasound in predicting spontaneous closure of patent duct arteriosus (PDA) in premature neonates. Methods One hundred and seventy premature neonates aged less than 37 weeks of gestation were enrolled. They were all admitted in the neonatal intensive care unit of Jinhua People′ s Hospital within 24 hours after birth. Echocardiographic examinations was conducted using GE′s Vivid I Portable color Doppler ultrasonography with routine cardiac probe (frequency 1.7-3.4 MHz) and high-frequency transducer (frequency 7.5 MHz). Up to the 7th day, the echocardiography was carried out every day after birth until the closure of PDA .They were divided to two groups according to whether spontaneous closure of PDA took place with in 7 days after birth (the control group) or not (the PDA group). There were 16 premature neonates in PDA group, including 6 male and 10 female. The mean gestational week at birth was (35.3±1.4) weeks. The mean birth weight was (2 330.9±325.5) g. Thirty-two premature neonates were included incontrol group, including 13 male and 19 female. The mean gestational week at birth was (35.0±1.3) weeks. The mean birth weight was (2 337.5±287.8) g. The clinical characteristics and echocardiographic parameters were compared between the two groups. Results The detection rates of high-frequency ultrasound and routine echocardiography were all 100%. The spontaneous closure rate of PDA in preterm infants at 24 hours, 48 hours, 72 hours were 18.8%(32/170), 61.2%(104/170), 78.8%(134/170) respectively. Within 7 days after birth, the closure rate was 90.6%(154/170), therefore the incidence of PDA in premature neonates was about 9.4%(16/170) in our study. The display rate of entire duct arteriosus using high frequency ultrasound was signiifcantly higher than that using routine ultrasound [82%(39/48) vs 46%(22/48), P0.05). To predict the spontaneous closure of PDA in preterm neonates within 7 days after birth by high frequency ultrasound, the sensitivity, specificity and accuracy were 87.5%, 90.6% and 66.5% respectively using the cutoff point of 1.55 mm. While the sensitivity, speciifcity and accuracy were 75%, 93.7%, 44.15%by routine echocardiography with the cutoff point of 2.36 mm. Conclusions High-frequency ultrasound can conifrm the diagnosis of PDA in preterm infants and it is better than routine echocardiography in depicting the structure of arterial duct. The larger PDA diameter was suggestive of the lower possibility of spontaneous close.