Prenatal evaluation of fetal atrioventricular valves by real-time 4D volume imaging with electronic matrix probe

The purpose of this study is to evaluate the feasibility using real-time four-dimensional (RT 4D) volume imaging with electronic matrix probe to observe the morphology of atrioventricular valves in normal and abnormal fetuses, measure the area and circumference of atrioventricular valves in normal fetuses and analyze the correlation with gestational age.

RT 4D volume imaging with electronic matrix probe was used to collect cardiac volume data of 162 normal fetuses with the gestational age from 22 to 32 weeks and 19 fetuses with atrioventricular valves abnormalities were also enrolled. All the volume data were analyzed and processed in real-time. The morphology of mitral and tricuspid valves was observed in surface mode. The area and circumference of valves were measured in a 4D render view at the end of diastole and analyzed the correlation with gestational age.

In 148 of 162 fetuses (91%), the 4D rendered image could be successfully obtained, which clearly showed the morphology of the atrioventricular valves. The area and circumference of mitral and tricuspid valves were positively correlated with gestational age (P < 0.01). Furthermore, 4D rendered images were successfully obtained in 17 of 19 fetuses (89%) with atrioventricular valves abnormalities.

The reference range of the area and circumference of atrioventricular valves in normal fetuses at different gestational weeks could be determined by using the RT 4D volume imaging with electronic matrix probe, which can provide certain diagnostic information for the clinic. The RT 4D images could display the valves morphology vividly in both normal and abnormal fetuses, including some subtle lesions which are not identified by traditional two-dimensional (2D) echocardiography. It is feasible to use the RT 4D volume imaging with electronic matrix probe to perform the prenatal evaluation in the fetal atrioventricular valves.