Congenital heart block (CHB) is an important model of passive autoimmunity occurring in one per 15,000-20,000 pregnancies. The association between conduction defects in an otherwise normally developing fetal heart and maternal autoantibodies to SSA/Ro and SSB/La ribonucleoproteins is well established. In the neonatal period, liver and blood cell abnormalities are also associated with these maternal antibodies and are grouped under the heading of neonatal lupus syndrome. Non-cardiac manifestations are transient, resolving at six months after birth, with the disappearance of maternal autoantibodies from the infant’s circulation. However CHB is irreversible because of the damage to the conducting system of the fetal heart. If the heart rate of the fetus is too slow, low output may cause hydrops fetalis. Therapeutic interventions include maternal plasmapheresis, steroid therapy, sympathomimetic therapy, premature delivery and fetal pacing. Echocardiography has become established as the method for the detection and monitoring of fetal arrhythmias. We think that physicians caring for pregnant woman should be aware of this entity for careful monitoring of the fetal heart rate and timing of maternal prophylaxis.

Keywords: konjenital kalp bloğu, neonatal lupus sendromu, maternal konnektif doku hastalığı, SSA/Ro-SSB/La antikorları, congenital heart block, neonatal lupus syndrome, maternal connective tissue disorders, SSA/Ro-SSB/La antibodies.