Ultrasound findings in fetal congenital heart block associated with maternal anti-Ro/SSA and Anti-La/SSB antibodies

We present the sonographic features of a second-trimester fetus diagnosed with a bradyarrhythmia at 19 weeks' gestation. The mother carried a diagnosis of Sjogren syndrome, including the presence of SSA and SSB antibodies. Ultrasound M-mode and fetal echocardiogram revealed the etiology of the bradycardia to be a complete fetal congenital heart block, likely due to transplacental passage of autoimmune anti-Ro/SSA and anti-La/SSB antibodies. Consequential to the congenital heart block, the fetus developed hydrops fetalis at 21 weeks' gestational age. We discuss the 2 major etiologies of congenital heart block and the implications in subsequent pregnancies.