Fetal Congenital Complete Heart Block: 2 Success Stories Through Multidisciplinary Care

Congenital complete heart block (CCHB) is a rare condition associated with significant fetal and neonatal mortality. It may present as an isolated conduction abnormality in association with autoimmune disease, or in conjunction with congenital heart defects including heterotaxy-polysplenia syndrome. Early prenatal diagnosis and coordinated perinatal care are critical for improving outcomes. We present 2 cases of prenatally diagnosed CCHB. The first occurred in a fetus with heterotaxy-polysplenia syndrome, and the second in the setting of maternal anti-SSA antibody exposure. Both fetuses developed progressive bradycardia, with heart rates declining to <50 beats/min, necessitating close fetal surveillance and individualized perinatal management. Preterm delivery and prompt placement of temporary pacing wires allowed initial stabilization before eventual definitive management, resulting in survival. The successful outcomes in these neonates highlight the critical role of multidisciplinary prenatal care, timely delivery planning, and early postnatal intervention in improving survival in fetuses diagnosed with CCHB.