Contribution of Fetal Tricuspid Regurgitation in First-Trimester Screening for Major Cardiac Defects

To estimate the potential value of fetal assessment for tricuspid regurgitation at 11-13 weeks of gestation in the prediction of major cardiac defects. We screened for aneuploidies by measuring fetal nuchal translucency thickness as well as assessing blood flow across the tricuspid valve for evidence of tricuspid regurgitation and in the ductus venosus for evidence of reversed A-wave at 11 0/7 to 13 6/7 weeks of gestation. The estimated performance of different combinations of increased fetal nuchal translucency, tricuspid regurgitation, and ductus venosus reversed A-wave in screening for major cardiac defects was examined. The study population of euploid fetuses included 85 cases with major cardiac defects and 40,905 with no cardiac defects. Fetal nuchal translucency above the 95th percentile, tricuspid regurgitation, or ductus venosus reversed A-wave was observed in 30 (35.3%), 28 (32.9%), and 24 (28.2%) of the fetuses with cardiac defects, respectively, and in 1,956 (4.8%), 516 (1.3%), and 856 (2.1%) of those without cardiac defects. Any one of the three markers was found in 49 of the fetuses with cardiac defects (57.6%, 95% confidence interval [CI] 47.0-67.6%) and in 3,265 of those without cardiac defects (8.0%, 95% CI 7.7-8.2%). Assessment of flow across the tricuspid valve improves the performance of screening for major cardiac defects by fetal nuchal translucency and ductus venosus flow.