Maternal autoantibody levels in congenital heart block and potential prophylaxis with antiinflammatory agents

Objective The importance of maternal autoantibody levels in congenital heart block and elucidation of maternal factors that may reduce disease burden require further clarification. Study Design Pregnancies complicated by maternal anti-Ro antibodies from 2007 through 2011 were retrospectively reviewed. Results In all, 33 women were followed up throughout pregnancy. Semiquantitative maternal anti-La levels were significantly higher in pregnancies complicated by fetal heart block of any degree (median difference, 227.5; P = .04), but there was no difference in maternal anti-Ro levels. In all, 94% of fetuses maintained normal conduction when the mother was treated with hydroxychloroquine or daily prednisone therapy throughout pregnancy, compared to 59% in the untreated group (odds ratio, 0.1; P = .04). Conclusion Pregnancies complicated by fetal heart block did not have higher levels of maternal anti-Ro antibodies. Maternal anti-La level may be a useful predictor of fetal heart block. Maternal treatment with either hydroxychloroquine or daily low-dose prednisone throughout pregnancy may provide a protective effect.