What is fetal echocardiography?
Current high-resolution echocardiographs allow us to visualize and examine cardiac structures, allowing early diagnosis of certain congenital alterations with important pathophysiological implications, which opens up the possibility of planning the most appropriate form and timing of delivery and thus providing early treatment to the newborn. The technique itself consists of performing an ultrasound scan focused on the heart by applying ultrasound, and is therefore harmless for both the mother and the fetus.
What is a fetal echocardiography for?
Congenital malformations are the main cause of neonatal mortality, with congenital heart disease being the most frequent, affecting up to one in every 100 newborns. Fetal echocardiography also allows us to detect arrhythmias or heart rhythm disturbances in the fetus.
In 2004 the Pediatric Committee of the American Society of Echocardiography and the European Association of Pediatric Cardiology established recommendations and guidelines for its performance.
When is it recommended that fetal echocardiography be performed?
Although it can be performed earlier, the first visit is usually between 18 and 20 weeks of gestational age. Depending on the pathology detected, if there is any pathology, the following visits will be scheduled, initially weekly in cases of rhythm disturbances.
A follow-up visit is also routinely scheduled between 29 and 32 weeks. In certain risk groups (such as diabetic pregnant women, or transient rhythm disturbances) this third trimester check-up should be performed in a protocolized manner.
What pathologies can be detected thanks to fetal echocardiography?
In general terms, we could say that it allows us to detect anatomical alterations of the cardiac structures (congenital heart disease) and rhythm disturbances or fetal arrhythmias. It also allows us to make a hemodynamic evaluation of the fetus, being able to detect hemodynamic alterations.
In which cases is it performed?
There are several controversies about the establishment of risk groups and screening techniques for congenital heart disease or fetal arrhythmias by routine obstetric ultrasound. In general, we can establish four main groups of indications for fetal echocardiography:
- Fetal indications: such as the presence of any extracardiac anatomical malformation, karyotype alteration, increased nuchal fold, multiple pregnancy (at least monochorionic), hydrops of non-immune cause, oligo/polyhydramnios, intrauterine growth retardation, and could even be considered in cases of in vitro fertilization, regardless of the number of fetuses.
- Maternal indications: due to the presence of congenital heart disease in the mother, intake of risk drugs or medicines (alcohol, indomethacin, antihypertensives, anticonvulsants, lithium, retinoic acid), congenital infection, maternal metabolic diseases such as diabetes or phenylketonuria, or the presence of other diseases such as arterial hypertension, lupus erythematosus, Sjögren’s, or mothers carrying anti-Ro and/or anti-La autoantibodies.
- Family indications: history of congenital heart disease in a previous child or first-degree relative, familial cardiomyopathy, or hereditary syndromes or diseases such as Marfan syndrome or tuberous sclerosis.
- Obstetric indications: due to diagnosis or suspicion of congenital heart disease, fetal arrhythmia or hemodynamic alteration of the fetus in the current gestation. It would also be indicated in cases in which the basic cardiac image cannot be obtained in the routine study.
If any abnormality is detected, what is the next step?
When a fetus is diagnosed with heart disease, a prognosis will be given, together with the data provided by the general obstetric studies and, if necessary, genetic studies, with the infant cardiologist providing information on the prognosis and management of the heart disease. Knowledge of the existence of heart disease in the fetus requires specific follow-up by pediatric cardiologists experienced in fetal cardiology and mutual counseling between obstetricians and cardiologists.
With this idea in mind, the different Fetal Cardiology programs have arisen in an attempt to provide early answers to families who have had a previous child with heart disease or to certain risk groups, to guide treatment in the case of rhythm disturbances when necessary, to advise on current criteria for decision-making in cases of severe heart disease, and to provide a type of assistance that is increasingly in demand in advanced societies.
For more information, please consult a specialist in pediatric cardiology.