[Rate of prenatal detection of congenital right heart defects]

Congenital right heart lesions (including tetralogy of Fallot, pulmonary valve stenosis, pulmonary atresia with intact ventricular septum, Ebstein's anomaly and dysplastic tricuspid valve) account for about 19% of congenital cardiac anomalies. We performed a retrospective study in order to assess the percentage of patients with significant right heart lesions (requiring therapy in the first year of life), which is detected prenatally and referred to a centre for perinatal treatment. From 1/1990 until 12/1997 congenital right heart lesions were diagnosed in 21 fetuses and 190 infants (211 patients. The majority of patients had tetralogy of Fallot (64%), less frequently we found critical pulmonary valve stenosis (9%), pulmonary atresia with intact ventricular septum (9%), tricuspid atresia (14%) and Ebstein's anomaly or dysplastic tricuspid valve (4%). Prenatally the cardiac anomaly was diagnosed in all 21 cases who were referred to our center (10%). The highest referral and detection rate was found among fetuses with Ebstein's anomaly or dysplastic tricuspid valve (5/8 patients = 63%) followed by fetuses with pulmonary atresia and intact ventricular septum (5/20 = 25%), critical pulmonary stenosis (4/18 = 22%) or tricuspid atresia (4/29 = 14%). The prenatal referral rate was disappointing in children with tetralogy of Fallot (3/136 = 2.2%). A higher prenatal detection rate of congenital right heart lesions can be achieved only by an improvement of prenatal screening including the 4-chamber view and the origin of the great arteries. A first step would be the inclusion of the fetal 4-chamber view into the routine examination during the 18th-20th week of pregnancy (stage 1 of a multistage concept of prenatal screening) and by assessment of the outflow tracts and the great arteries in pregnancies associated with risk factors or anomalies of the fetus (stage 2 and 3 of a multistage concept).