Summary and conclusionsThe association between infants with congenital heart block (CHB) and the presence or later development of maternal systemic lupus erythematosus or other connective-tissue disease (CTD) was reviewed in 67 cases. In 24 cases CHB was diagnosed at or before birth. Of nine necropsies on affected infants, seven showed endomyocardial fibrosis. The results suggest that one in three mothers who deliver babies with CHB have or will develop CTD.The association is probably explained by placental transfer of a maternal antibody. Awareness of the association may lead to prevention of the birth of children with CHB and better neonatal care of affected children.
IntroductionComplete congenital heart block (CHB) occurs in only about 1 in 20 000 pregnancies.1 About a quarter of the cases are associated with a heart malformation, but in the remainder the aetiology is unknown. Pregnancy in women with systemic lupus erythematosus (SLE) is also rare, occurring in about 1 in 1500.2 In 1976 we discussed a case in which congenital heart block and maternal SLE were associated in relation to two others recorded, certain features suggesting that the association was not fortuitous.4 Since then at least 30 cases have been reported and we have traced a further eight earlier case reports. It now appears that SLE is of major importance in the aetiology of