Fetal Third-Trimester Functional Cardiovascular Abnormalities and Neonatal Elevated Bilirubin Level

The aim of the study was to analyze the neonatal outcomes of fetuses with diagnosed functional cardiovascular abnormalities, also considering the connection with neonatal hyperbilirubinemia.

It was an observational study of 100 neonates who had fetal echocardiography examinations in the third trimester (mean gestational age during the last echocardiography was 34 ± 3 weeks and mean birth weight was 3550 g). There were two groups: A: normal heart anatomy + no functional anomalies; group B: normal heart anatomy + functional abnormalities. Hyperbilirubinemia was defined as a bilirubin level of >10 mg%.

In group A, there were 72 cases and only 5 cases despite having normal heart anatomy and normal heart study that presented additional problems. In group B (28 cases), the prenatal functional findings included tricuspid regurgitation (TR) (15 cases, 53%), pericardial effusion (4 cases, 14%), myocardial hypertrophy (4 cases, 14%), cardiomegaly (2 cases, 7%), abnormal bidirectional blood flow across the foramen ovale (3 cases, 11%), aneurysm of atrial septum (2 case, 7%), abnormal E/A ratio for mitral and tricuspid valve (1 case, 3%), bright spot (3 case, 11%), abnormal Doppler flow in ductus arteriosus compared to aortic arch (difference >60 cm/s) (1 case, 3%), supraventricular tachycardia (SVT) (1 case), and mitral regurgitation (1 case, 3%). In group A (n = 72 cases), bilirubin levels of >10 mg/dL were observed in 8% of newborns. In group B (n = 28), bilirubin levels of > 10 m/dL were observed in 46% of cases and TR was present in group B in 53% of cases (15/28 cases). The difference between group A and B in terms of elevated bilirubin levels was statistically significant (p < 0.001).

In the case of fetal normal heart anatomy and normal heart study, a good neonatal outcome may be expected. When fetal cardiovascular functional abnormalities in normal heart anatomy are detected, with special attention paid to tricuspid valve regurgitation, a neonatal elevated bilirubin level (mean 11 mg/dL, range 10-15 mg/dL) may be expected.