Unique coexistence of tetralogy of Fallot and congenital heart block linked to maternal autoantibodies in a Down syndrome fetus: a case report

Abstract We report a rare fetal presentation of tetralogy of Fallot and complete atrioventricular block linked to maternal anti-Ro antibodies. However, trisomy 21 was confirmed postnatally. Despite pacemaker implantation, the neonate died on day 55 due to pulmonary complications. This complex case highlights diagnostic and management challenges involving tetralogy of Fallot, Down syndrome, and complete heart block associated with maternal autoantibodies.