The Comparative Research Of The Morphology Of Fetal Foramen Oavle Valve And Postnatal Foramen Oavle Closure State

Objective: To explore the relationship of the prenatal foramen ovale(FO),the structure and length of foramina ovalve valve(FOV),the blood flow of foramen valve and postnatal patent foramen closure time and the atrial septum defect by using two-dimensional echocardiography and color doppler technique。Methods: 300 fetuses at 20 to 40 weeks gestation were measured by fetal echocardiography and were demonstrated to be normal. 280 fetuses were followed up in 1 week,1month,6months after birth. A set of color Doppler ultrasonic system(GE Voluson E8)was empoyed before birth,probe frequency of 4-8MHz,and Toshiba SSA-880 was used after the birth, probe frequency of 2.5 MHz.FO, the length of FOV and septum secundum,the length from FO to crisscross and the blood flow of FO were measured by fetal echocardiography. The postpartum echocardiography were followed up to observe the patent foramen closed.SPSS13.0 statistical software was used for data analysis.Results:1 There was significant difference in the length of FO and the aperture ratio between each segment with increasing gestational age, enlarging FO, growthing FOV, increasing aperture ratio, slowing velocity of the FO.2 According to the 2-dimensional echocardiograohy, the FOV were dividied into 2 type: single flat and single curve.3 There was no significant difference between different morphological FOV from influence of the FOV moyphology to FO closing by the single factor analysis.4 There was significant difference in FO closure rate between different reexamination times,which verified the growth rule of FO closure.5 There was significant difference in the ratio of prenatal atrium and ventricular in the fetuses with FO of limiting exoteric. There was no significant difference in the ratio of postnatal atrium and ventricular.Conclusion:The examination of FO and FOV by echocardiography was simple,and the image is clear.The parameters monitoring of FO and FOV,which could evaluate the FO closure state, can be used as indicators of fetal heart development.For the fetuses with FO of limiting exoteric,especially in the third trimester,the current study could be used to guide obstetrician for clinical intervention.Fetal echocardiography is simple and safe,which has an important guideline value for clinical medicine.