EP14.08: Complete atrioventricular block in fetus with anti‐Ro/La antibodies negative: a eight‐year followed‐up study

Abstract

A 28-year-old woman, P1G0 at 30 weeks of gestation, maternal auto-antibodies (anti-Ro/La) were negative. The fetal echocardiogram showed cardiac structures were normal, and showed complete atrioventricular block (CAVB) on the fetus. The atrial rate was regular at 130–140bpm, while the ventricular rate was only 68bpm. She underwent a Caesarean section and delivered a healthy female baby at 38 weeks 8years ago. An ECG after birth confirmed the diagnosis of CAVB. Since then, the child have developed well, and have good academic performance. The child continues to perform well without any pills and pacemaker. Now the child is 8 years old and Echocardiography showed normal structure of the heart and the ventricular rate was 58bpm. At present, approximately half of all CAVB cases are caused by associated congenital heart defects, and almost 40% of CAVB are immune-mediated, especially with anti-SSA/Ro and/or anti-SSB/La antibodies, only about 10% of CAVB are auto-antibodies negative. In patient with CHD, the prognosis of CAVB was strongly associated with the type of CHD; In isolated CAVB fetus with maternal auto-antibodise, the prognosis of CAVB is different according to the situation of the fetal and newborn; As the low incidence in the fetus of CAVB with auto-antibody negative, the nature prognosis of it are obsure. In our report the child with isolated auto-antibody negative is alive with no asympotem from the first time till now. It is noteworthy that the child performed well without any medicine treatment or pacemaker, and her heart rate ranges around 68 bpm at last follow-up. The exact reason of this phenomenon remains unclear, and might have a relationship with the raletively higher ventricular rate (≥ 55 bpm), which we infered to be associated with its high pacing site. Thus, based on our clinic practice if the fetus presenting with seronegative CAVB and the heart rate is more than 55, it might have a favorable prognosis.