Doppler waveforms from the pulmonary arterial system in normal fetuses and those with pulmonary hypoplasia

Color, pulsed and power Doppler were used to image the fetal pulmonary vasculature in 150 normal pregnancies and ten pregnancies in which the fetus had bilateral multicystic dysplastic kidney disease (MCDK) and associated pulmonary hypoplasia. The normal fetuses had a high resistance pattern in the main pulmonary artery vasculature. There were no significant changes in the resistance of the main pulmonary artery, right pulmonary artery and left pulmonary artery, with increasing gestational age. In the peripheral pulmonary arteries the resistance was less with an increase in diastolic flow, with advancing gestation. All fetuses with MCDK died. This group did not have significantly different Doppler waveforms in the main pulmonary arteries, but Doppler signals from the peripheral pulmonary arteries showed a high resistance pattern quite different from that of normal fetuses. Doppler measurements of the peripheral pulmonary artery may give additional information useful in diagnosing pulmonary hypoplasia.