An echogenic focus within the fetal heart (left or right ventricle) is due to mineralization within a papillary muscle. 90% resolve by the third trimester. As an isolated finding, it is often insignificant and no further follow-up reuired. However, if it is found with numerous other soft markers, there can be a risk for chromosomal anomalies (Down's most commonly). So try not to worry. 4% of normal fetuses have them. They will likely not even need a follow-up for you. Only 25% of fetuses with down's have them (along with many of the other markers). When they discuss the results with you, if there were any other markers they may refer you for an amniocentesis and genetic screening. Did you have a nuchal translucency ultrasound at 12-14 weeks?