Apical four-chamber ultrasonography as screen for congenital heart disease

Two cases of monozygotic twins, in each of which one fetus was prenatally diagnosed as having a heart anomaly

In each of the 2 cases of monozygotic twins reported here, 1 of the fetuses was suspected, as a result of a prenatal ultrasonographic examination, of having congenital heart disease (CHD). One of twins (Case 1) had a hypoplastic left heart (HPLH), coarctation of the aorta (CoA), mitral stenosis (MS), and an atrial septal defect (ASD). Of the other twins (Case 2), 1 fetus had pure pulmonary atresia (PPA) and tricuspid regurgitation (TR). In Case 1, the fetus with CHD had a single umbilical artery, the other had otherwise. In Case 2, the fetus with CHD had a velamentous insertion and an accessory placenta, and the other fetus had a marginal insertion. These findings suggest that environmental factors such as blood flow, blood pressure and so on have a role in the etiology of CHD.

Screening for congenital heart disease with the four-chamber view of the fetal heart

OBJECTIVE

Our objective was to determine the efficacy of the four-chamber view of the fetal heart in routine ultrasonographic examination as a screening tool for congenital heart defects.

STUDY DESIGN

A prospective cohort study compared the detection rate of congenital heart defects among 5336 pregnant women screened with the ultrasonographic four-chamber view of the fetal heart from 1987 through 1989 with that among 3680 patients examined ultrasonographically without the four-chamber view during the 2 preceding years (1985 through 1986). All patients were followed until delivery or termination of pregnancy, and clinical or autopsy confirmation of prenatal findings were obtained on all cases.

RESULTS

The overall incidence of congenital heart diseases was 5.2 per 1000 (47/9016). During the years 1985 through 1986 15 neonates with congenital heart diseases were identified, seven of which were prenatally diagnosed (sensitivity 43%). During the period 1987 through 1989 a four-chamber view of the fetal heart was obtained in 95% of cases; 32 cases of congenital heart disease occurred, 26 of which were diagnosed antenatally (sensitivity 81%; p = 0.01). Two false-positive diagnoses were made during the second time period, giving a specificity of 99.9%.

CONCLUSION

The four-chamber view of the fetal heart is easily obtained, does not significantly increase the duration of a routine ultrasonographic examination, and has an excellent sensitivity for the identification of congenital heart diseases.