Fetal cardiac function during the first trimester of pregnancy.

Chromosomally normal first trimester fetuses with an increased nuchal translucency measurement have an elevated risk of congenital heart defect (CHD). so there is an increased demand for imaging the fetal heart during the first and early second trimesters of pregnancy.Echocardiographic and anatomical correlations in firsttrimester fetuses show that by 11 weeks' gestation, the position of the fetal heart within the chest is similar to that in later gestation, and the spatial relation of the great arteries and their relative sizes are similar to those on second-trimester scans by 12 weeks' gestation.In the first trimester during the heart analysis it's possible value: anatomic structure (size, rate), hemodynamic development through analysis of these waveforms and flow patterns (inflow and outflow waveforms of the diastolic filling and the systolic ejection) and modification during the first trimester.