First-degree heart block in the fetus of an anti-SSA/Ro-positive mother: reversal after a short course of dexamethasone treatment.
Isolated congenital heart block is almost invariably associated with the presence of antibodies to SSA/Ro and SSB/La antigens in the maternal circulation. Once established, third-degree congenital heart block is permanent. However, a lesser degree of autoantibody-associated heart block in a fetus can be reversed if it is recognized and treated early enough with fluorinated glucocorticosteroids. The only method available clinically for the recognition of first-degree heart block in a fetus is measurement of the mechanical PR interval by pulsed Doppler echocardiography. This is the first report of a fetus in whom a diagnosis of first-degree heart block and the consequent decision to intervene were based solely on this technique. In addition, the first-degree heart block resolved completely after only 2 weeks of dexamethasone treatment, and the heart rhythm remained stable throughout the remainder of the pregnancy despite early discontinuation of therapy due to oligohydramnios.
Vesel
Samo
S
Department of Pediatrics, Cardiology, Unit, University Medical Center Ljubljana, Ljubljana, Slovenia. samo.vesel@mf.uni-lj.si
Mazić
Uros
U
Blejec
Tanja
T
Podnar
Tomaz
T
D000328:Adult; D000974:Antibodies, Antinuclear / Q000097:blood*; D003907:Dexamethasone / Q000627:therapeutic use*; D018619:Echocardiography, Doppler, Pulsed; D005260:Female; D005318:Fetal Heart; D005938:Glucocorticoids / Q000627:therapeutic use*; D006327:Heart Block / Q000000981:diagnostic imaging / Q000188:drug therapy*; D006801:Humans; D011247:Pregnancy / Q000097:blood / Q000276:immunology*; D016896:Treatment Outcome; D016216:Ultrasonography, Prenatal
D000974:Antibodies, Antinuclear; D005938:Glucocorticoids; C035356:SS-A antibodies; D003907:Dexamethasone