ABSTRACT
M-mode, pulsed Doppler and Doppler color flow mapping, in addition to two-dimensional echocardiography, have greatly improved imaging of the fetal heart through identification of abnormal cardiac anatomy and rhythm in utero. The early detection of cardiac disturbance in utero permits alteration in obstetric management such as delivery in a high-risk center for optimal neonatal care and/or decision in optimal delivery time. We report two cases of the neonatal arrhy-thmia which were observed by fetal echocardiography. In the first case, female baby showed neonatal arrhythmias including tachycardia and brady-cardia until 3 days after birth, and then turned to bradyarrhythmia due to non-conducted atrial bigeminy. These events lead us to review the fetal echocardiographs of the patient carefully. Premature atrial contractions were observed in her fetal echocardiography. At 2 months after birth, the patient's electrocardiogram showed normal sinus rhythm. Severe neonatal bradycardia of the second case was due to congenital complete heart block, identified clearly by electrocardiogram after birth. This case also showed complete heart block in her fetal echocardiography. After insertion of the temporary pacemaker, cardiomegaly was improved. Both the neonate and the mother had positive anti-SSA/Ro autoantibody. But any other symptoms and signs of neonatal lupus did not appear in the neonate. Patient's mother also did not show any symptoms and signs of systemic lupus erythematosus. Since the prognosis depends upon the cause of bradyarrhythmia in fetus and neonates, differential diagnosis is important in obstetric management and optimal neonatal treatment.