Text Box: IMPACT OF FETAL ECHOCARDIOGRAPGHY ON THE OUTCOME OF CONGENITAL HEART DISEASE IN HONG KONG YAM MC, SUNG R, MOK G Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, China Objective: To review the outcome of fetal echocardiograms and their impact on the congenital heart disease (CHD) in a teaching hospital. Methods: 139 consecutive fetal echocardiograms done on 131 pregnant women in the Prince of Wales Hospital in the past five years were reviewed and compared with all the newly diagnosed CHD at the same period. Fetal echocardiography was performed using standard method. All live birth babies had a complete physical examination after birth and an echocardiography was performed to confirm the prenatal findings if necessary. All aborted fetuses had a detailed autopsy by the pathologist. Results: 39 (30%) patients were found to have abnormal findings, 36 of them were referred because of an abnormal 4 chamber view detected by obstetricians. The abnormalities included ventricular septal defect (4), atrioventricular septal defect (3), transposition of great artery (1), Fallot’s tetralogy (5), coarctation of aorta (1), dysplastic tricuspid valve (1), total anomalous pulmonary venous drainage (1), hypoplastic left heart syndrome (2), double outlet right ventricle (3), aortic stenosis (1), truncus arteriosus (1), dextrocardia (1) and complex cyanotic heart (15). 21 mothers chose to terminate the pregnancy because of severe CHD and resulted in 8.6% decrease in the incidence of CHD in this period. One patient who had an antenatal diagnosis of double outlet right ventricle was found to have normal connections of the great vessels but grossly dilated RV and persistent pulmonary hypertension. The calculated false positive rate of fetal echocardiography is 2.5%, there was no false negative result. Conclusion: Fetal echocardiography as a prenatal screening test has a major impact on the CHD both medically and ethically. Although the false positive rate of fetal echocardiography is low, it warrants extra caution in the interpretation and management of all abnormal results. 2417