Fetal echocardiography: retrospective review of clinical experience and an evaluation of indications.

Objective: To assess the indications, use, and yield of fetal echocardiography.

Methods: We reviewed our 8-year experience with fetal echocardiography at a large health maintenance organization in northern California to assess the yield of abnormal findings for each indication and the accuracy of prenatal cardiac diagnosis. The study included 915 fetuses undergoing fetal echocardiography between 18-38 weeks' gestation because of accepted indications. All live-born infants had the presence or absence of congenital heart disease (CHD) confirmed postnatally.

Results: Family history of CHD led to 34% of all fetal echocardiography studies, with a detection rate of 0.7%. Maternal diabetes mellitus accounted for 28% of all studies, with a detection rate of 1.2%. Exposure of mothers to a potential teratogen led to 48 studies, but no abnormalities were detected. Only 4% of fetal echocardiograms were obtained because of a suspected heart defect noted on a screening obstetric sonogram; this indication had a detection rate of 68% and yielded by far the most cases of severe CHD. Based on the expected occurrence rate of severe CHD in our closed referral system, only about 15% were referred for fetal echocardiography and detected prenatally.

Conclusion: Basing fetal echocardiography referral on risk factors misses most clinically significant detectable CHD.