Comparison of Reference Values and Z Scores of Pulse-Doppler Waveforms of Fetal Pulmonary Artery and Aorta

Abstract

Background: Doppler-derived fetal pulmonary artery acceleration time (PAAT) and acceleration-to-ejection time ratio (AT/ET) are important as predictors of a variety neonatal pulmonary diseases. The evaluation of PAAT and PA AT/ET are meaningful when simultaneous right and left heart studies are done. The unique cardiovascular physiology in the fetus, as the only period of life with physiologic systemic pulmonary hypertension, overemphasizes the significance of simultaneous study. However, studies on comparative fetal velocitometry of PA and aorta are scarce. Objectives: The aims of this study were to provide reference values for peak systolic velocity (PSV), pulsatility index (PI), acceleration time (AT), ejection time (ET) and AT/ET ratio of PA and aorta in the singleton pregnancies with healthy fetuses. We compared these Doppler parameters of PA and aorta. Methods: A cross-sectional study was performed on 146 fetuses. We measured PSV, PI, AT, ET and AT/ET in the PA and aorta and compared the values. We evaluated the correlation between these parameters and the fetal gestational age (GA). Results: Mean ± SD of gestational age of fetuses were 21 ± 4 weeks. PSV, AT and AT/ET of PA and aorta increased with gestational age.

Comparison of Fetal Main Pulmonary Artery Doppler Wave Forms between Normally Grown and Growth Restricted Fetuses: A Case-Control Study

“…Placenta, although is not placed directly on the course of pulmonary artery flow, it can indirectly affect the PA flow on its way to the descending aorta [21,22]. Pulmonary artery flow faces three different downstream resistances; the highresistance-non-aerated fetal lungs, the lower resistance-aortic vascular bed and placental vascular bed with the lowest resistance in normal pregnancy [9]. The MPA-PSV reflects right ventricular systolic function and in our study it reduced in growth restricted fetuses.…”