Research progresses of hemodynamics in aortic isthmus during fetal period / 中国医学影像技术

ABSTRACT

In the fetal circulation,the right and left cardiovascular system are positioned in parallel,and the aortic isthmus behaves as a shunt that connecting both up-and downstream circulations,allowing the fetuses to increase or reduce the amount of blood directed to the brain and heart depending on the degree of oxygen supply from the placenta.Doppler blood flow waveform of the fetal aortic isthmus can be obtained from the traditional longitudinal aortic arch view or the more recently described three vessels and trachea view of the fetal upper mediastinum.The aortic isthmus blood flow has a characteristic shape with end-systolic notch during the third trimester pregnancy and gradually deepen with the increase of gestational age.Doppler blood flow waveform of the aortic isthmus is closely related to fetal brain and heart function,and its reverse signal in the diastolic phase shows the poor intrauterine fetus.