Transabdominal Sonographic Quantitative Analysis of the Fetal Cardiac Width in Third Trimester of Gestation

Antenatal ultrasonography is noninvasive and done on routine basis in our institution. A four chamber view of the fetal heart is done as a part of regular sonographic examination of the fetus. Most cases of congenital heart disease are of structural rather than functional origin. The heart grows very rapidly during the third trimester (positive allometry). The linear increase of the fetal heart shows a strong and significant correlation with the increase of both femur length and BPD. This suggests that non-invasive analysis of cardiac data can be useful for prenatal detection of congenital heart disease or for the gestational age. 1 If a malformation is diagnosed in the third trimester, the fetus should be delivered at a facility equipped to care of the infant with congenital heart disease. The fetal heart was studied with transabdominal sonography in 132 single normal pregnancies in third trimester Measurement of cardiac width (transverse diameter) of the heart was taken. Gestational age was assessed by fetal parameters that are biparietal diameter, femur length and abdominal circumference as per the norms in one of the Mumbai's medical teaching institute and tertiary care center. This study verified that the heart grows very rapidly during the third trimester (positive allometry). The linear increase of the fetal heart shows a strong and significant correlation with the increase of biparietal diameter, femur length and abdominal circumference. Relationships between the cardiac data and fetal age, biparietal diameter, femur length and abdominal circumference were explored by allometry and linear regression analysis in order to estimate cardiac growth rates during third trimester. This suggests that noninvasive analysis of cardiac data can be useful for the assessment of gestational age or for prenatal detection of congenital heart disease.