Prediction of Perinatal Mortality in Ebstein's Anomaly Diagnosed in the Second Trimester of Pregnancy

Objectives: Firstly, to describe the outcome of a series of fetuses with Ebstein's anomaly (EA) and, secondly, to study the utility of different second-trimester echocardiographic parameters to predict fetal and neonatal mortality.

Methods: 39 fetuses with EA diagnosed between 18 and 28 weeks of gestation were included. Fetal echocardiography included the cardiothoracic ratio (CTR); right atrial (RA) area index; displacement of the tricuspid valve (TV); tricuspid regurgitation; pulmonary artery; and ductus arteriosus flow characteristics. Additionally, 2 novel parameters were obtained: the relative RA area ratio (RA area/cardiac area) and the TV displacement index (TVDI, TV displacement distance/longi-tudinal diameter of the left ventricle). Correlation between the echocardiographic variables and the primary outcome of perinatal mortality or survival at 1 year of life was evaluated.

Results: From the initial cohort, 8 cases were excluded due to complex congenital heart defects. Termination of pregnancy (TOP) was performed in 15 cases, and fetal death was diagnosed in 3 cases. In the live-born cohort of 13 patients, 4 died in the neonatal period, yielding a perinatal survival rate of 29 and 56%, respectively, after excluding TOP cases. Compared with survivors, nonsurvivors showed a significantly higher CTR (56.7 ± 16.2 vs. 42.6 ± 8.6; p = 0.04), relative RA area ratio (0.39 ± 0.13 vs. 0.25 ± 0.05; p = 0.01), and TVDI (0.62 ± 0.17 vs. 0.44 ± 0.12; p = 0.03) at diagnosis. The best model to predict perinatal mortality was obtained by using a scoring system which included the relative RA area ratio and TVDI (AUC 0.905 [95% CI 0.732-1.000]).

Conclusions: Fetuses with a relative RA area ratio ≥0.29 and TVDI ≥0.65 at the second trimester have the highest risk of dying in the perinatal stage.