Prenatal Ultrasonography For Fetal Heart Of The Second-trimester

ObjectiveTo study the anatomic structure and hemodynamics of the normal fetal heart from 21 to 25 gestational weeks.MethodsDiameters of the cardiac chambers, main vessels and ductus arteriosus and peak flow rates of aortic valve, pulmonary valve, atrio-ventricular valve, ductus arteriosus and ductus venosus were assessed in 203 normal and singleton fetuses of gestational age from 21 to 25 weeks. The relationships between the quantitative value and gestational weeks were assessed by correlation and regression analysis.Results1. Diameters of the fetal cardiac chambers, main vessels and ductus arteriosus were increased with gestational weeks;2. The diameter ratio of pulmonary artery to ascending aortic artery was not changed with gestational weeks;3. Velocity of atrio-ventricular valve was not changed with gestational weeks;4. trio-ventricular valve flow was double wave and A>E;5. Velocities of Aortic valve, pulmonary valve, ductus arteriosus and ductus ConclusionsThe reference values of diameters for the cardiac chambers, main vessels and peak flow rates for aortic valve, pulmonary valve, atrio-ventricular valve, ductus arteriosus and ductus venosus from 21 to 25 gestational weeks, which would be useful for the prenatal screening of the fetal heart.