A fetal echocardiogram is a specialized, non-invasive ultrasound examination that focuses exclusively on the structure and function of an unborn baby’s heart. This procedure uses sound waves to create moving images, providing a detailed assessment that goes far beyond the view obtained during a routine prenatal anatomy scan. By closely examining the heart’s chambers, valves, and major blood vessels, healthcare providers can evaluate how the organ formed and whether it is working properly. The test offers a comprehensive view of the fetal heart’s anatomy, rhythm, and blood flow patterns.
When This Specialized Scan Is Necessary
A fetal echocardiogram is ordered when there is an elevated risk for congenital heart disease or a concern raised during a standard ultrasound. Maternal factors are one indication, such as having a pre-existing medical condition like insulin-dependent diabetes mellitus or systemic lupus erythematosus. Exposure to specific medications during pregnancy, including some anti-epileptic drugs or prescription acne treatments, can also increase the risk, leading to a referral.
Another common reason for the scan is a family history of congenital heart defects (CHDs) in a previous child or a parent. Fetal indications, which are concerns directly related to the baby, frequently prompt the test. These include an abnormal heart rhythm (arrhythmia) detected on a routine check-up or a suspected structural heart problem. The finding of a major abnormality in another organ system also warrants a specialized cardiac evaluation, as heart defects often occur alongside other issues.
Preparing for the Examination
Preparation for a fetal echocardiogram is minimal, as the procedure is similar to a standard abdominal ultrasound. A full bladder is usually not required, though some clinics may request a moderately full bladder for examinations performed before 24 weeks. There are no specific dietary restrictions, and no fasting is required, since the scan’s accuracy depends on the baby’s position and activity.
The most important step is ensuring the healthcare team has access to all relevant medical information, including any history of heart conditions in the family or known maternal health issues. The examination is scheduled during the second trimester, most often between 18 and 24 weeks of gestation, when the fetal heart structures are large enough to be clearly visualized. Patients should plan for the appointment to take a significant amount of time, requiring anywhere from 30 minutes to two hours, depending on the complexity and the baby’s cooperation.
The Step-by-Step Procedure
The examination begins with the expectant parent lying comfortably on an examination table, often tilted slightly to the side to improve blood flow. A clear, water-based gel is applied to the abdomen to help sound waves travel between the skin and the transducer. A specially trained sonographer or pediatric cardiologist then uses the hand-held probe, known as a transducer, to gently press and move across the abdomen.
The transducer emits high-frequency sound waves that reflect, or “echo,” off the dense structures of the baby’s heart. These echoes are instantaneously captured by the probe and translated into a real-time, moving image displayed on a computer screen. The sonographer systematically obtains specific views to assess the heart’s anatomy.
These views include the four chambers of the heart, the valves between them, and the outflow tracts, which are the main vessels carrying blood away from the heart. The sonographer also uses Doppler technology, a feature that highlights and measures the direction and speed of blood flow through the heart and major arteries. Color Doppler imaging helps visualize any abnormal shunting or leaks by displaying blood movement in different colors.
Because the fetal heart is small and the baby often moves, the procedure requires patience and meticulous effort to capture all necessary angles and measurements. The technologist must wait for the baby to move into optimal positions to ensure a complete study, which explains why the scan duration can be lengthy.
Interpreting and Discussing the Findings
Once the imaging is complete, the captured video clips and still images are reviewed by a pediatric cardiologist, a physician specializing in heart problems in children and unborn babies. This specialist analyzes the findings to determine if the heart’s structure and function are within expected limits, or if a congenital heart defect or rhythm irregularity is present. A normal result means that no cardiac abnormalities were found and the pregnancy can continue with routine prenatal care.
If an abnormality is identified, the pediatric cardiologist meets with the family, often immediately following the scan, to discuss the diagnosis, its implications, and the prognosis. This consultation focuses on forming a precise plan for the remainder of the pregnancy and beyond, which may involve additional testing, such as a fetal MRI or genetic testing. For complex defects, the care team coordinates with high-risk obstetricians and neonatologists to ensure the baby is delivered at a medical facility with a specialized cardiac care unit. Early diagnosis allows families and medical providers to prepare for any necessary treatment, which could include medication or surgery immediately following birth.