EC Paediatrics

Congenital complete atrioventricular block (cAVB) is a rare condition, with potentially life-threatening consequences. The most common etiology is maternal autoimmune disease, particularly associated with anti-SSA/Ro and anti-SSB/La antibodies, which can cross the placental barrier and cause damage to fetal cardiac conduction tissues. We present the case of a male neonate born at 39 weeks' gestation via Caesarean section due to fetal bradycardia. The mother, with a history of chronic polyarthralgia, and was later diagnosed with Behcet's disease, discovered secondary to the atrioventricular block in her baby. found to have positive anti-SSA/Ro and anti-SSB/La antibodies. On admission, the newborn had a heart rate of 70 beats per minute and an electrocardiogram confirmed complete 3^rd-degree atrioventricular block. Despite this, the infant remained asymptomatic and did not require pacemaker implantation. This case highlights the importance of early diagnosis and careful monitoring of neonates with cAVB, particularly in those with maternal autoimmune conditions, as immediate intervention may not always be necessary. Close follow-up is essential to ensure timely management if clinical deterioration occurs.

 Keywords: Congenital Atrioventricular Block (cAVB); Neonatal Bradycardia; Maternal Autoimmune Disease; Anti-SSA/Ro Antibodies; Anti-SSB/La Antibodies; Fetal Cardiac Conduction Disorder; Pacemaker

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