Prenatal check-ups are crucial, with several key examinations being particularly important: the first ultrasound at 7-8 weeks to confirm intrauterine pregnancy; the second ultrasound and Down syndrome screening between 15-18 weeks; a 4D ultrasound for anomaly screening at around 6 months, and if necessary, a fetal echocardiogram. Following these, an ultrasound 1-2 weeks before delivery is conducted to estimate fetal weight, check fetal position, and ensure all indicators are normal. Most fetal heart developmental abnormalities can be diagnosed through imaging results during these prenatal check-ups.
Clinically, the most commonly used method for fetal heart examination is the fetal echocardiogram, which can diagnose the majority of heart abnormalities. Particularly for pregnant women with a family history of heart disease, fetal echocardiography can generally be performed from the 16th week of pregnancy, with the optimal period being between 20-24 weeks. The four-chamber view is the most important plane for screening congenital heart disease (CHD) in fetuses. Conditions such as hypoplastic left and right ventricles, mitral and tricuspid valve stenosis or atresia, complete endocardial cushion defect, Ebstein's anomaly, single ventricle, and large ventricular septal defects can all be detected in the four-chamber view. In recent years, the use of 4D ultrasound with spatiotemporal image correlation (STIC) technology has allowed for real-time dynamic display of three-dimensional volumetric information of the fetal heart, providing a more intuitive view of the anatomical structures and spatial relationships of the atria, ventricles, and great arteries. If 4D ultrasound or fetal echocardiography strongly suggests a heart developmental abnormality, further examination with fetal cardiac MRI may be considered. This technique can compensate for the limitations of fetal echocardiography, and the combination of both methods can essentially confirm various types of congenital heart disease. For fetuses diagnosed with severe congenital heart disease, termination of pregnancy and induced labor are often recommended.
