Genetic sonography: the historical and clinical role of fetal echocardiography.

The association of congenital heart defects with trisomy 21 was reported over 50 years ago and heart defects remain one of the most common and lethal abnormalities present postnatally in individuals affected by Down syndrome1–4. The purpose of this Editorial is to review the use of second-trimester fetal echocardiography as an adjunct to the genetic sonogram from a clinical perspective, based on my experience over the past 20 years5–13. The following topics are discussed as they relate to trisomy 21: (1) the incorporation of ultrasound evaluation of the fetal heart as part of the genetic sonogram and comparison of it with other screening modalities from a historical perspective; (2) the postnatal incidence of congenital heart defects; (3) the prenatal incidence of structural and functional heart abnormalities; (4) the relative risk for various cardiac findings; and (5) the suggested use of fetal echocardiography as part of the genetic sonogram given current screening technologies.