Fetal echocardiography in the diagnosis of congenital heart disease.

Fetal echocardiography provides an opportunity to diagnose congenital heart disease as early as the midtrimester of pregnancy, allowing for proper planning of perinatal care and counselling of the parents. This paper reviews the accuracy and outcomes of fetal cardiac ultrasound studies at The Prince Charles Hospital over the past 4 years. A total of 43 fetuses, of gestational ages 16-39 weeks, were studied. The indications for these were: previous sibling with cardiac anomaly (16 cases); abnormal heart on obstetric ultrasound scan (USS) (13 cases); abnormalities found on obstetric USS with normal appearing heart (one case); fetal bradycardia (seven cases); fetal tachycardia (four cases); irregular fetal heart beat (two cases). At birth all fetuses assessed because of a previously affected sibling were normal. Of the 13 referred because of structural heart lesions suspected on obstetric USS, eight were abnormal, four were normal and one was terminated without autopsy. Important rhythm disturbances occurred in nine of the 11 referred because of abnormal heart rates. One false positive diagnosis of a possible coarctation was made, and in four cases an abnormality was noted on USS but the diagnosis was not completely correct. Nine of the 19 infants with abnormalities detected have died. Fetal echocardiography is an accurate and useful method of diagnosing congenital heart disease in utero. Although the mortality of affected fetuses is high, antenatal diagnosis allows planning of medical care and offers the greatest chance of a successful outcome.