[Pulsed Doppler echocardiographic findings in 100 normal Chinese fetuses]

To evaluate the feasibility and reliability of Doppler echocardiography in assessing fetal hemodynamics, pulsed Doppler echocardiography was performed in 100 normal Chinese fetuses and blood flow velocities through atrioventricular and semilunar valves were measured. The success rate in recording the maximal velocities were 76% for mitral flow, 86% for tricuspid flow, 94% for aortic flow and 49% for pulmonary flow. The flow velocities increased with fetal developments, and the increase became significant after 26 gestational weeks when the fetuses were in acceleration of growth. The maximal velocity (Vp) and velocity integral (VI) of flow through the tricuspid valve were significantly higher than those through mitral valve. Although there was no significant difference of Vp and VI in the flow between aortic and pulmonary valves, the ratio of acceleration time to ejection time (AT/ET) of flow through the pulmonary valve was significantly lower than that through the aortic valve.