P19.12: Ultrasonic screening of fetal cardiac structure in the first trimester

Abstract

To explore the feasibility and clinical significance of ultrasonic screening of fetal cardiac structure at 11-13+6 weeks gestation. Transabdominal ultrasonography was used for two-dimensional (2D) imaging combined with colour Doppler. Fetal heart screening was performed in 156 pregnant women (156 fetuses) between 11 and 13+6 weeks gestation in our hospital from February to December in 2016 when they underwent nuchal translucency (NT) screening. We analysed the frequencies that adequate views of specific cardiac structures were obtained (display rates). All of the patients had follow up fetal echocardiograms in the second trimester. The display rates of cardiac structures in 156 fetuses were as follows: four-chamber view (4C) 95.5% (149/156), left ventricular outflow tract (LVOT) 78.2% (122/156), right ventricular outflow tract (RVOT) 79.4% (124/156), three vessel view (3V) 58.9% (92/156), aortic arch (AA) 72.4% (113/156), ductus arteriosus (DA) 60.2% (94/156), superior vena cava/inferior vena cava (SVC/IVC) 82% (128/156). The display rates for fetuses at 11-11+6 weeks (16 cases) were 4C 81.2% (13/16), SVC/IVC 50% (8/16), while those of LVOT, RVOT, 3V, AA and DA were all below 50%. The rates of the fetuses at 12-12+6 weeks(100 cases) were 4C 96% (96/100), RVOT 84% (84/100), LVOT 83% (83/100), AA 74% (74/100), DA 61% (61/100), SVC/IVC 86% (86/100), 3V 54% (54/100). In fetuses at 13-13+6 weeks (40 cases), the rates were 4C 100% (40/40), LVOT 82.5% (33/40), RVOT 82.5% (33/40), AA 85% (34/40), DA 70% (28/40), 3V 77.5% (31/40), SVC/IVC 85% (34/40). Three fetuses with cardiac defects were identified in the first trimester. They were Tetralogy of Fallot, pulmonary stenosis, and ventricular septal defect. All of them were confirmed in the second trimester. The display rates of fetal cardiac structures at 12-13+6 weeks are significantly higher than fetuses at 11-11+6 weeks, especially the LVOT and the RVOT. It is feasible to screen for severe cardiac malformations with ultrasound in the first trimester.