The study of the fetal heart is done by means of the fetal echocardiography, which consists in an abdominal ultrasound performed in pregnant women but centered in the baby’s heart.

Cardiac malformations are the most frequent congenital anomalies, but the question is if 100% of the cardiac diseases in the maternal uterus are detected. Although it is true that it is not possible to rule out all of them, most of the clinically significant cases can be diagnosed.

Most babies with congenital heart diseases are found in low risk mums. Because of that, it is important to do a good evaluation in the 20th week of gestation, usually by means of a gynecologic ultrasound performed in the second trimester, although it is possible to detect the most serious ones in very early stages of pregnancy.

The Association for European Paediatric Cardiology, in its recommendations for the practice of fetal echocardiographies, proposes a minimum of data that must be obtained in every study. It establishes three levels: the basic one for all fetal ultrasounds studies which is based in the analysis of the four chambers of the heart, an intermediate level aimed to improve the results from the general study which includes examination of the outflow tracts but without offering a specialized service, and the third level for fetal cardiologists who assist women with high-risk pregnancies.

Among the risk factors in which a detailed fetal echocardiogarphy is recommended we find the following: first, a family history of congenital heart diseases or genetic syndromes; second, high fetal risk as increased nuchal translucency, cardiac rhythm anomalies, suspicions of cardiac malformation in previous studies or fetal malformations; and last, high risk because of mother’s chronic diseases as diabetes or lupus, some infections, medication, or even maternal age older than 35 years if no genetic study has been carried out.

Due to the larger number of criteria which require a more detailed study and also to technical and professional improvements, there has been an increase in the early detection of these anomalies. That gives more specific information for prenatal diagnosis and, above all, for prognosis, which allows mums and dads to have more data so that they can take decisions and get ready for a baby with a heart disease which, in a very high percentage, has a remedy.