Ductus venosus revisited: a Doppler blood flow evaluation in the first trimester of pregnancy.
The functional role of the fetal ductus venosus (DV) is still poorly established. Few reports are available in the literature concerning assessment of fetal venous return during the late first trimester of pregnancy. Our objective was to determine the normal Doppler blood velocity waveform in the human fetal DV as early as 10-13 weeks gestation. Adopting strict methodological concerns, 61 Doppler blood flow evaluations of the DV considered technically acceptable were selected. Using transvaginal Doppler ultrasound, several DV haemodynamic parameters were assessed: peak systolic and diastolic velocities, time-averaged velocity, maximum velocity during atrial contraction, pulsatility index and fetal heart rate (FHR). Except for the FHR, no significant variations were observed for the above mentioned parameters during this period, and no correlation could be established between FHR and the different flow velocity parameters. Further knowledge about DV haemodynamics in the early phases of pregnancy may make a valuable contribution to the understanding of fetal venus return to the heart and cardiac function.
Montenegro
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N
Department of Obstetrics and Gynecology, S. João Hospital, Porto, Portugal.
Matias
A
A
Areias
J C
JC
Barros
H
H
D001783:Blood Flow Velocity; D005260:Female; D005865:Gestational Age; D006340:Heart Rate, Fetal / Q000502:physiology; D006801:Humans; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D018608:Ultrasonography, Doppler; D016216:Ultrasonography, Prenatal; D014471:Umbilical Veins / Q000502:physiology; D014680:Veins / Q000000981:diagnostic imaging* / Q000196:embryology*; D014682:Vena Cava, Inferior / Q000196:embryology