Detection of fetal congenital heart disease in a low-risk population.

Our purpose was to evaluate the efficacy of level two ultrasound screening for the detection of congenital heart defects (CHD) in a low-risk population by using three standardized cuts. Within a period of four years a total of 6727 pregnant women of a low-risk population undertook several ultrasound examinations on the basis of screening for fetal malformations. All ultrasound examinations were performed by three experienced doctors. At every single scan three standardized cuts (apical and lateral four-chamber view, crossing over of the great arteries) were obtained in order to detect congenital heart defects. Of 87 CHDs (1.33 per cent of the examined women) 39 (43.8 per cent) were diagnosed prenatally. The detection rate was 10/48 (20.8 per cent) in the presence of VSD, ASD2 or combined ASD2 + VSD, the detection rate was 29/39 (74.3 per cent) in the presence of other forms of congenital heart disease. None of the 38 missed cases in the first group but three of the ten missed CHDs in the second group had emergency neonatological problems. Aneuploidy and/or other malformations existed in 22/87 cases of CHD. The obstetrical management was changed in nearly all cases after the diagnosis of a CHD. Twenty-two women opted for termination of pregnancy because of additional fetal malformations or chromosomal defects. Five women were transferred prenatally to a tertiary centre for neonatal cardiac surgery. Ten deliveries were performed in the presence of a neonatologist. Good detection rates for CHD can be achieved in a low-risk population on the basis of level two ultrasound screening by using the above mentioned three cuts and thus, the perinatal mortality and morbidity can be improved.