Heart disease in infancy: A window to the world of fetal cardiology

Advances in ultrasound technology and its widespread application have enabled the discovery of the most serious cardiovascular malformations in 16-18 week fetuses. The type of CVM is a major, but not the only, factor determining parental decision regarding pre and post-natal management. In a significant proportion of cases, CVM in fetuses is associated with extracardiac defects. The data of the Baltimore-Washington Infant Study shows that approximately 25% of all newborns with CVM (and almost a third of newborns with the most severe CVM, which are theoretically more readily detectable by fetal ultrasound) have non-cardiac malformations. The frequency and structure of associated defects in cases with different forms of CVM are reported. In some cases the extracardiac defects may be the primary determinant of outcome. In other cases defects of other systems may be manifestations of serious chromosomal abnormalities. Therefore, detailed ultrasound and cytogenetic study of each fetus with CVM detected by ultrasound is a necessary part of fetal evaluation. If the parents opt for continuation of the pregnancy, a geneticist should be involved in clinical evaluation of the infant after birth, especially if extracardiac abnormalities are evident or suspected. If DiGeorge sequence or Williams syndrome is suspected in an infant, specific molecular tests will be necessary to confirm (or to exclude) the diagnosis.