G. Mielke et N. Benda, Blood flow velocity waveforms of the fetal pulmonary artery and the ductusarteriosus: reference ranges from 13 weeks to term, ULTRASOUN O, 15(3), 2000, pp. 213-218
Objective To establish reference ranges for blood flow velocity waveforms o
f the fetal main pulmonary artery and the ductus arteriosus during the seco
nd and third trimesters of pregnancy.
Methods A prospective cross-sectional echocardiographic study was performed
in 222 normal fetuses from 13 to 41 weeks of gestation using high resoluti
on/color Doppler ultrasound equipment.
Results Gestational age-specific reference ranges are given for peak veloci
ty across the pulmonary valve, velocities in the ductus arteriosus, peak sy
stolic velocity in the ductus arteriosus-to-peak velocity across the pulmon
ary valve ratio, ductal systolic velocity-to-diastolic velocity ratio, duct
al resistance index and ductal pulsatility index. In the ductus arteriosus,
increasing fetal heart rate was significantly associated with increasing e
nd-diastolic velocity and decreasing systolic-to-diastolic ratio, decreasin
g resistance index, and decreasing pulsatility index.
Conclusions Based on a prospective study in more than 200 normal fetuses, t
he data provide gestational age specific reference ranges for blood flow ve
locity waveforms of the fetal pulmonary artery and the ductus arteriosus. T
he reference ranges may be helpful in prenatal diagnosis of cardiac malform
ations and ductal obstruction from 13 to 41 weeks of gestation.