Congenital Atrioventricular Block: Comprehensive Review of Pathophysiology, Management, and Future Therapeutic Directions

Congenital atrioventricular block is a congenital conduction defect that can present in utero, at birth, or within the first 3 months of life. Most cases are immune-mediated, caused by maternal anti-Ro/SSA or anti-La/SSB antibodies passing across the placenta and causing injury to the fetal conduction system; however, genetic mutations and structural heart diseases have also been implicated. Detection rates have been improved by maternal antibody screening and fetal echocardiography, but optimal diagnostic tests and risk stratification are needed for better outcomes. Prenatal treatments such as fluorinated corticosteroids, intravenous immunoglobulin, and hydroxychloroquine attempt to decrease inflammation and prevent recurrence, but a permanent, complete AV block may still occur. Postnatal pacemaker implantation is critical and reduces mortality rates dramatically, but possesses complications related to pacing cardiomyopathy, device failure, and arrhythmia. Newer technologies, such as conduction system pacing, biological pacemakers, and imaging-based applications, offer a hopeful future for better outcomes, but this progress is dependent upon multidisciplinary collaboration, prospective studies, and future data.