Correlation between tricuspid regurgitation and fetal cardiac structure or signs and prenatal genetic testing abnormalities in fetuses at 12+ 0 to 16+ 0 weeks of gestation

This study aimed to investigate the correlation between tricuspid regurgitation (TR) in fetuses at 12+ 0 to 16+ 0 weeks of gestation and fetal cardiac structure, signs, and prenatal genetic testing abnormalities. A prospective collection of dynamic four-chamber view (4CV) color Doppler ultrasound images of fetuses at 12+ 0 to 16+ 0 weeks of gestation was performed to screen for TR. The correlation between the non-TR and TR groups in fetal cardiac structure or signs and prenatal genetic testing abnormalities was analyzed, as well as the correlation between different grades of TR and fetal cardiac structure, signs, and prenatal genetic testing abnormalities. (1) In this study, 1018 early gestational fetuses were included, with a 100.0% detection rate of dynamic 4CV color Doppler ultrasound images. (2) Among the 1018 fetuses, 942 were in the non-TR group, and 76 were in the TR group, yielding a TR detection rate of 7.5%. The TR group comprised 62 cases (81.6%) of mild TR, 6 cases (7.9%) of moderate TR, and 8 cases (10.5%) of severe TR. In the TR group, 12 cases (15.8%) had cardiac structural or sign abnormalities or prenatal genetic testing abnormalities, among them, there were 11 cases (14.5%) of cardiac structure or signs abnormalities, and 8 cases (10.5%) of prenatal genetic testing abnormalities.TR occurrence rate is about 6.4% in normal fetuses. The risk of cardiac structural or echocardiographic abnormalities in the TR group was 17 times higher than that in the non-TR group, and the risk of prenatal genetic testing abnormalities in the TR group was 25 times higher than that in the non-TR group. After refining the TR grade, the proportion of mild and severe abnormalities of TR in cardiac structure or signs and prenatal genetic testing abnormalities gradually increased. (3) In the early stages of pregnancy, we observed significant differences in the prevalence of hypertension and diabetes between the non-TR group and the TR group (P < 0.05), the prevalence of maternal hypertension and diabetes were 2.7% and 4.0% respectively. (4) In the early stages of pregnancy, there were no significant differences in cardiac structure or echocardiographic signs of abnormalities, nor in prenatal genetic testing abnormalities between the non-TR group and the mild TR group (P > 0.05). However, significant differences were observed in these abnormalities between the non-TR group and the following TR groups: moderate TR, severe TR, moderate + severe TR, and mild + moderate + severe TR (P < 0.05). (5) We found no significant difference between moderate TR and severe TR in cardiac structural or echocardiographic abnormalities and prenatal genetic testing abnormalities (P > 0.05). However, statistically significant differences were observed between mild TR and severe TR, as well as between mild TR and moderate + severe TR, in cardiac structural or echocardiographic abnormalities and prenatal genetic testing abnormalities (P < 0.05). At 12+ 0 to 16+ 0 weeks of gestation, after refining the grading of TR, the incidence rates of mild to severe TR in terms of cardiac structure or signs and abnormal prenatal genetic testing continuously increased with the severity of TR. Mild TR can be considered physiological, while moderate and severe TR are regarded as pathological. Refining the grading of TR provides important clues for screening cardiac structure or signs and chromosomal abnormalities in first-trimester fetuses, offering reliable clinical evidence with high application value.