Suboptimal Imaging on Obstetric Ultrasound Should Prompt Early Referral for Fetal Echocardiography

Recent studies suggest that suboptimal cardiac imaging on routine obstetric anatomy ultrasound (OB-scan) is not associated with a higher risk for congenital heart disease (CHD) and, therefore, should not be an indication for fetal echocardiography (F-echo). We aim to determine the incidence of CHD in patients referred for suboptimal imaging in a large catchment area, including regions that are geographically distant from a tertiary care center. We conducted a retrospective chart review of patients referred to Seattle Children's Hospital (SCH) and SCH Regional Cardiology sites (SCH-RC) from 2011 to 2021 for F-echo with the indication of suboptimal cardiac imaging by OB-scan. Of 454 patients referred for suboptimal imaging, 21 (5%) of patients were diagnosed with CHD confirmed on postnatal echo. 10 patients (2%) required intervention by age one. Mean GA at F-echo was significantly later for suboptimal imaging compared to all other referral indications (27.5 ± 3.9 vs 25.2 ± 5.2 weeks, p < 0.01). Mean GA at F-echo was also significantly later at SCH-RC compared to SCH (29.2 ± 4.6 vs 24.2 ± 2.9 weeks; p < 0.01). In our experience, CHD in patients referred for suboptimal imaging is higher (5%) than previously described, suggesting that routine referral for is warranted. Furthermore, while suboptimal imaging was associated with a delayed F-echo compared to other indications, this delay was most striking for those seen at regional sites. This demonstrates a potential disparity for these patients and highlights opportunities for targeted education in cardiac assessment for primary providers in these regions.