This abnormality, abbreviated as EIF, is one of the more common findings seen on a 20 week anatomy scan. (One of my children had this!).
With respect to the ultrasound, it is an area, located in your baby’s cardiac tissue that is more “bright” or “echogenic” compared to the surrounding cardiac tissue when visualized with the ultrasound. It is imperative to understand that this has absolutely nothing to do with the cardiac function and has no relation to cardiac abnormalities or defects. It is simply an ultrasound finding that is seen in nearly 5% of normal pregnancies. Again, this is a very small area, (usually less than 3mm) that is more “bright” on the ultrasound, with the same brightness of the fetal bone, as opposed to the surrounding less dense tissue. It appears to be caused by small calcification of the papillary muscle of the heart.
The importance of an EIF is that it may be associated with potential chromosomal problems with the baby. This includes Down syndrome, (Trisomy 21) or other chromosomal abnormality. Up to 20-25% of babies with Down syndrome will have this finding. However, nearly 5% of chromosomal normal babies may have this as well. Current indications are that for a woman at low risk, this finding of echogenic foci alone DOES NOT increase risk for chromosomal anomaly.
The “brightness” initially seen on the anatomy scan typically resolves in the third trimester. The loose association with chromosomal abnormality will not change even when the EIF resolves. Genetic testing can be helpful and indicated to reassure normal chromosomes.