Fetal echocardiography: results in high-risk patients.

The results of 140 fetal cardiac scans in 124 high-risk obstetric patients (16 to 40 weeks' gestation) are presented. Sixty patients were scanned for high genetic or environmental risk (group 1); 31 because of fetal abnormality detected on routine ultrasound scanning (group 2) and 37 because of arrhythmias (group 3). Three patients were in two groups. The standard echocardiography views, ie, long-axis, great vessel short axis, four chamber, and aortic arch were obtained in 72, 95, 96, and 55%, respectively. All scans in group 1 were diagnosed as normal. In group 2, complex cardiac abnormalities were detected, the presence of fetal cardiac failure and its cause were clarified, and serious cardiac malformations were excluded. Arrhythmias in group 3 were diagnosed correctly and fetal hemodynamics assessed. A small number of lesions were not detected or diagnosed. The factors interfering with detection of lesions were abnormalities of the intrathoracic or abdominal cavity, inadequate amniotic fluid, and size of lesions. Major cardiac structures or abnormalities could be identified, and abnormal hemodynamics caused by arrhythmias and structural lesions assessed. Unnecessary intervention was prevented in five cases and conversely the need for acute intervention was indicated in seven cases. Fetal echocardiography remains a specialized investigation that has an important role in the management of some high-risk pregnancies.