What Is Fetal Echocardiography & How Is Performed? Its Purpose

Fetal echocardiography is an extremely helpful imaging technique for diagnosis of fetal heart anomalies when the baby is still in the womb. It is similar to ultrasound sonography, a frequently used imaging technique for detecting problems in abdomen and pelvis. Fetal echocardiography allows the pediatric cardiologist to view all the four chambers of fetal heart, identify any defects in heart structures, abnormalities in the rhythm and its function.

Usually this test is done in the second trimester. This high end machine sends sound waves through a transducer from the surface of abdomen.

The waves echo back to the machine. The machine creates echocardiogram picture of the fetal heart which is analyzed by the pediatric cardiologist.

What Is The Purpose Of Fetal Echocardiogram?

Fetal echocardiogram is not a routine test that is performed on all pregnant women. The basic ultrasound test in most cases is useful to view all the four chambers of heart and its function. However, some fetuses require more detailed imaging such as fetal echocardiogram in following circumstances:

  • Parents having a history of heart defect.
  • History of sibling having heart valve defect or any other structural heart defect.
  • History of drinking alcohol and drug abuse during pregnancy.
  • Mother taking certain medicines that may put the fetus at risk of suffering from heart problems. Medicines used for epilepsy etc.
  • Pregnant woman suffering from diabetes mellitus, phenylketonuria, autoimmune disease such as systemic lupus erythematosus (SLE).
  • Pregnant woman having history of rubella infection during pregnancy.
  • Chromosomal disorder detected after an amniocentesis test.
  • A routine sonogram shows enlarged fetal heart, arrhythmia or alteration in the position of fetal heart.

There are some obstetricians who are well trained to perform this test. Normally, the test is carried out by a technician who has specialized in the field of imaging technique. Once the test is performed a pediatric cardiologist will analyze and evaluate the films.

There is no associated risk to the pregnant woman or the unborn fetus with fetal echocardiography as this technique depends on the sound waves and there is no radiation involved.

How Is Fetal Echocardiogram Performed?

The pregnant woman does not need any prior preparation. The time period may be half hour to one hour for the test. The test is simple and it is just similar to ultrasound that is performed as a routine during pregnancy. The machine used is called echocardiogram. There are two standard imaging modalities used for fetal echocardiography; transabdominal and transvaginal for detecting congenital cardiac defect.

  • Transabdominal fetal echocradigraphy technique is same as that for sonogram. Pregnant woman is told to lie down on the table. She has to expose her abdomen. The technician or the doctor will apply lubricating jelly on the skin of abdomen. It prevents friction between the skin and transducer or the probe which sends sound signals in the pelvis and abdomen. The transducer is rubbed all over the abdomen. Through the probe, the machine sends high frequency sound waves to the fetal heart. They are reflected back and the computer catches them, evaluates and analyzes the waves. After the procedure, the jelly is cleaned and the woman can go home.
  • Transvaginal fetal echocradiography is performed through vagina. A probe or transducer is introduced in the vagina. Sound waves are passed through transducer. The reflected waves will create the picture of heart of the fetus. It is beneficial in early months of pregnancy. The dimensions of four chambers are better viewed and the cardiac defect is easy to detect by this method in early pregnancy period.

The test results if normal, means there is no congenital cardiac defect noted. If the doctor detects any abnormality, he may recommend further investigations such as fetal MRI etc. It is important to remember that fetal cardiography can also be sometime inconclusive as some defects may be difficult to detect.