Should we treat congenital heart block with fluorinated corticosteroids?

Cardiac involvement is the most severe manifestation of neonatal lupus. It is usually diagnosed as an advanced (second or third degree) atrio-ventricular (AV) congenital heart block (CHB) starting around 20 weeks of gestation. At this gestational time, a window of opportunity might exist, and fluorinated corticosteroids (FS) have been attempted as a therapeutic option. Unfortunately the quality of the studies is methodologically low, due to the retrospective design and to the rarity of autoimmune CHB. Some case reports and small case series basically suggested a possible utility of FS, mainly in the context of incomplete CHB, while larger observational retrospective studies did not find any efficacy of FS either on mortality, on the rate of pacemaker implantation, to reduce the degree of incomplete CHB or to reduce the development of cardiomyopathy. Of note the distinction between complete and incomplete AV block may be very difficult and time consuming in utero. Overall FS should not be recommended in CHB, but might be considered for a short time for a recent incomplete CHB.