Accuracy of antenatal ultrasound diagnosis assessed by Gold Standard – postmortem

Abstract

Objective: To evaluate the accuracy and assess the indications of fetal echocardiography to diagnose structural heart disease in our high risk population, by an obstetric team. Methodology: Over a 4-year period, a transabdominal echocardiography was performed in 912 high risk pregnancies for congenital heart disease at 18-38 weeks of gestation. In the last 140 cases, an early examination combining either the transvaginal or the transabdominal route at 13-16 weeks was also carried out. Follow up was obtained from neonatal examinations and autopsies. The main indications for referral were: pregestational diabetes mellitus, family risk, increased nuchal translucency, suspected cardiac anomaly at screening ultrasound, women at high risk of chromosomal abnormality reluctant to invasive test, suspected arrhythmia, single umbilical artery, exposure to teratogens, and pregnancies affected by a chromosomal abnormality. Results: There were 79 (8.6%) major congenital heart defects, and most of them were yielded in the group of screening by ultrasound. Seventy of them (88.6%) were diagnosed correctly as abnormal prenatally. Atrioventricular septal defects (21 cases) and hypoplastic left ventricle syndrome (12 cases) were the most prevalent heart anomalies in the fetus. Isolated septal defects and coarctation of the aorta were the most difficult lesions to detect, being the ones with false positive and negative diagnosis. Another four cases of non-significant (<3 mm, no surgery nor medical treatment required) ventricular septal defects were overlooked during gestation, but closed by the sixth month of life. Fifteen apparently normal cases were lost to follow up. Conclusion: Our obstetric team results, in accordance with others previously published, show a good effectiveness to diagnose congenital heart anomalies. Most major detectable cardiac anomalies occur in the group without previously-known risk. Fetal echocardiography is optimized by a team strategy of imaging by obstetricians/high risk obstetric scanners (O) and fetal pediatric cardiologists (FPC). We retrospectively examined 1037 studies (1995)(1996)(1997)(1998)(1999), and identified 249 cases of major congenital heart disease. The O diagnosis was compared to the FPC diagnosis and postnatal diagnosis. The rate of complete accurate diagnosis for O and FPC diagnosis were 59% (17% false positive, 41% negative), respectively. Major differences in diagnosis or detail were found in 79 patients after FPC was completed and in 35/79 (44%) this was judged to have potential significant impact on management and prognosis counseling. The complementary roles of O and FPC remain important. FPC can contribute with additional detail in some cases which may significantly impact on counselling and planning. F03Factors influencing the prenatal detection of structural congenital heart diseases S.-F. Wong, F.-Y. Chan, R. Cincotta, A. Lee-Tannock & C. Ward Background: Congenital heart disease is the commonest congenital anomaly, but the reported antenatal detection rate varies widely from ...