The Detection Rate of Cardiac Anomalies at 11–13+6 Week Scan Using Four Chamber View and Three Vessel View

Abstract

The primary aim of this study was to assess the feasibility of fetal cardiac evaluation at 11-13?6 weeks by assessing the four chamber and three vessel views. The secondary aim was to assess detection rates of cardiac anomalies at this gestational age. This was a prospective study done over 1 year. It included 355 patients who presented to a routine antenatal service and opted for prenatal genetic screening and anomaly scan at 11-13?6 weeks corresponding to a CRL of 45-84 mm. Four chamber view and three vessel view were examined in both gray scale and color Doppler using transabdominal scanning and transvaginal scanning. A follow-up was done at 18-22 weeks and at delivery. Major cardiac anomalies were seen in 5 (1.4 %) fetuses screened at 11-13?6 weeks. Two fetuses with cardiac anomalies (0.5 %) could not be detected at this gestation and were picked up at the 18-22 week scan. Extracardiac anomalies detected in the first trimester scan were 14 (3.9 %). Nuchal translucency (NT) of more than 3 mm was found in 19 (5.3 %) patients. Nuchal translucency of more than 3 mm was present in 3 (60 %) fetuses with cardiac defects seen at 11-13?6 weeks. Increased NT of more than 3 mm was found in 6 (43 %) patients having noncardiac anomalies. Four (1.1 %) patients had both cardiac and noncardiac anomalies detected at first trimester scan. When CRL was 76-85 mm, the cardiac anomaly detection rate was maximum (3.8 %) compared to detection at CRL 66-75 mm (1.2 %), 56-65 mm (0), 45-55 mm (2.2 %). Noncardiac defects had a detection rate of 2 (4.4 %) at CRL 45-55 mm, 4 (3.6 %) at CRL 56-65 mm, 7 (4.5 %) at CRL 66-75 mm, 1 (1.9 %) at CRL 76-85 mm. Overall detection of major fetal cardiac anomalies at 11-13?6 weeks was 1.4 % and noncardiac anomalies was 3.9 %. This supports the opinion that first trimester can be used for detection of major congenital heart diseases and noncardiac anomalies along with fetal aneuploidy screening. Detection of anomalies in the first trimester helps patient in early decision making and counseling for further management. Keywords 11-14 week scan Á Echocardiography Á Congenital heart defects Á Nuchal translucency Á Four chamber view Á Three vessel view