Fetal Congenital Heart Block

Abstract

Objective: To report on the pathophysiology, diagnosis, and management of fetal congenital heart block. Design: Case series. Setting: University hospital. Patients: A 33-year old secundigravid with fetal congenital heart block secondary to structural heart disease; a 28-year old primigravid with isolated fetal congenital heart block secondary to maternal autoantibodies; and a 44- year old grand multipara with fetal congenital heart block, resolved. Interventions: Close fetal monitoring with cardiotocography, fetal wellbeing studies using ultrasonography with color Doppler velocimetry, and pacemaker insertion in the neonatal period. Main Outcome Measures: Cardiotocography and ultrasonography with Doppler revealed fetal congenital heart block. Further work-up involving autoantibody testing and fetal 2D-echocardiography revealed the underlying pathophysiology and classification of congenital heart block depending on the presence of structural heart anomalies or the existence of concomitant maternal disease. Results: The first two cases exemplified the different categories of congenital heart block: Case 1 illustrated heart block secondary to structural heart disease and Case 2 illustrated the isolated type secondary to maternal autoantibodies. Case 3 showed the typical clinical picture wherein no further progression but resolution of heart block symptoms occurred prenatally. Conclusions: This report emphasizes the importance of a high index of suspicion in the early diagnosis of fetal congenital heart block. Proper management for such cases entails close monitoring using available technology and not necessarily medical management in utero.