Non-invasive low-risk fetuses still have strong left ventricular echoes, this may be caused by physiologic reasons and is not a manifestation of cardiac anomalies. Left ventricular echogenicity is a sonographic manifestation after ultrasound examination, which may be formed by thickening of the tendon cords within the ventricle, mineral deposition in the center of the papilla, early ischemic changes of the terminal branches of the coronary arteries within the papillary muscles, and incomplete perforation of the tendon cords of the papilla muscle, and the majority of the left ventricular echogenicity is gradually blurred, narrowed, and even disappeared with the increase of the gestational month of strong echogenicity points. Fetal left ventricular strong echogenicity to do non-invasive DNA test results in a low risk, indicating that the fetus is unlikely to suffer from chromosomal abnormalities of the disease, even if the test of non-invasive DNA for a low risk, but also does not say that the fetus will not have the problem of strong echogenicity of the left ventricle, just that the problem of strong echogenicity of the left ventricle of the fetus should be physiological. The accuracy of non-invasive DNA testing is not 100%, and the possibility of accidents cannot be ruled out.