Complete heart block in fetus – A rare combination of maternal autoimmune disorder and fetal structural cardiac disease – A case report and review of literature

Abstract

Majority of rhythm disturbances detected by fetal echocardiography are self-limiting. Appropriate work up of dysrhythmias is essential to prevent further damage of fetal conducting system and to initiate fetal therapy thereby reducing fetal losses. 25 year old Primi, 31 weeks of gestation, no comorbidities, was referred to our Antenatal OPD as severe fetal bradycardia. Antenatal Fetal Echo revealed third degree heart block with no evidence of hydrops. Maternal serum workup revealed autoimmune etiology. Fetal therapy started and Pregnancy followed up weekly till term gestation to deliver an alive baby by vaginal delivery. Baby was diagnosed to have Large ASD with a large PDA having bidirectional shunt by paediatric cardiologist. Surgical management was done by PDA ligation and permanent pacemaker. Unfortunately, baby succumbed due to respiratory failure and sepsis, as it was high risk complete heart block with multifactorial causation. Fetal bradyarrhythmia need to be evaluated carefully both for maternal autoimmune disorders and intrinsic cardiac causes of fetus. This case is reported for its rarity of having both etiologies presenting together as third degree or complete heart block.