Diagnosis Of Pulmonary Arterial Atresia By Prenatal Ultrasonography In Early And Late Pregnancy

【Objective】 To investigate the value of prenatal ultrasonography in the diagnosis and differential diagnosis of pulmonary atresia in early and middle and late pregnancy.【Methods】 Twenty-one cases of fetal pulmonary atresia with labor induction and anatomical confirmation in our hospital from December 2017 to December 2020 were selected.The prenatal echocardiographic characteristics and classification were analyzed and compared with the postpartum pathological anatomy and casting results.The analysis was conducted in combination with the chromosomal examination results.At the same time,the development status of the right cardiac system in the middle and late pregnancy with intact ventricular septal pulmonary atresia was evaluated and the changes of hemodynamics were observed.The left/right ventricular length diameter,right ventricular wall thickness,annulus diameter,tricuspid blood inflow time,tricuspid regurgitation velocity and other indicators were measured respectively,and the indicators were compared with the normal fetal group.【Results】 In this group,21 fetuses with pulmonary atresia were confirmed by anatomy,including 8 fetuses with PA/IVS and 13 fetuses with PA/VSD.Among them,there were 8 PA/IVS fetuses(1 case in early pregnancy and 7 cases in middle and late pregnancy).Ultrasonic diagnosis was correct in 6 cases,the prenatal ultrasound diagnosis accuracy was 75.0%(6/8),and 2 cases were misdiagnosed(1case was misdiagnosed as severe pulmonary artery stenosis with complete ventricular septum and 1 case was misdiagnosed as PA/VSD).In this study,there were 13 PA/VSD fetuses(2 in early pregnancy and 11 in middle and late pregnancy).Ultrasonic diagnosis was correct in 11 cases,the prenatal ultrasound diagnosis accuracy was 84.6%(11/13),and 2 cases were misdiagnosed(1 case was misdiagnosed as double outlet of right ventricle and 1 case was misdiagnosed as permanent trunk artery).Compared with the control group during middle and late pregnancy,the tricuspid Z value,RV/LV,TV/MV,PV/AV,TID/CC of PA/IVS fetal group were lower than those of the normal fetal group,and the TRPSV and right ventricular wall thickness were higher than those of the normal fetal group,the differences were statistically significant(P < 0.05).【Conclusion】 Multi-section scan based on four-chamber cardiac view and three-vessel tracheal view is helpful for the diagnosis of pulmonary atresia in early pregnancy.Prenatal echocardiography can diagnose and accurately classify pulmonary atresia in middle and late pregnancy.Pregnant women with PA/VSD fetuses should be advised to undergo genetic testing to determine whether the fetus is associated with chromosomal abnormalities,particularly microdeletions of 22q11.