Which Intrauterine Treatment for Autoimmune Congenital Heart Block?

Abstract: Autoimmune Congenital Heart Block (CHB) is considered an immune mediated manifestation, caused by the\r\naction of maternal autoantibodies anti-Ro/SSA and anti-La/SSB on fetal cardiac tissues. The incidence of CHB is 2% in\r\nanti-Ro/SSA positive women, 3% when both anti-Ro/SSA and anti-La-SSB are positive. In the subsequent pregnancies\r\nthe risk of recurrence is 9 times higher.\r\nThe antenatal diagnosis of CHB is possible by the measurement of the “mechanical” PR interval with fetal echocardiography.\r\nWhen CHB is diagnosed, an intrauterine therapy is possible to increase the atrioventricular conduction speed and improve\r\nthe fetal outcome.\r\nAuthors recommend maternal treatment with fluorinated steroids, as Dexamethasone or Betamethasone, which reduce the\r\nantibody-mediated inflammatory damage of nodal tissue. Other possibilities are the maternal administration of betasympathomimetics,\r\nin order to increase the fetal heart rate.\r\nIn the last years three cases of complete CHB in infants of women affected by autoimmune disease were treated in our\r\ncentre. They were treated in utero with the maternal administration of Betamethasone 4 mg/day soon after the diagnosis\r\nuntil delivery. After delivery, all children needed cardiac pacemaker. The long-term outcome is good in all cases.