2026/05/27 by S. Lertvutivivat, L Gotha, K. Papneja +4
Medicine · #Cardiac Arrhythmias and Treatments #Cardiovascular Issues in Pregnancy #Systemic Lupus Erythematosus Research
paper · doi:10.1002/uog.70247
openalex publication_date 2026/05/27 · openalex created_date 2026/05/28 · openalex updated_date 2026/07/27
A 31-year-old healthy woman (gravida 4 para 1, with two previous miscarriages) presented to The Hospital for Sick Children, Toronto, ON, Canada, for a fetal echocardiogram at 17 + 0 weeks' gestation. She had a previous child who was diagnosed postnatally with antibody-mediated sinus node dysfunction and had therefore been routinely taking 400 mg/day hydroxychloroquine prophylactically for 3 months prior to conception. The echocardiogram revealed normal fetal heart rate (FHR) with normal atrioventricular (AV) intervals. Titer dilutions were used to assess the levels of maternal anti-Ro52, anti-Ro60 and anti-La autoantibodies, each of which were elevated (1415 CU, 24 548 CU and > 15 500 CU, respectively). As the pregnancy was high risk, the patient received a home FHR monitor with instructions to assess the FHR twice daily and was scheduled for weekly fetal echocardiograms. At 21 + 3 weeks, the patient reported irregular findings on home FHR monitoring. Within 3 h, an urgent fetal echocardiogram demonstrated advanced second-degree AV block with periods of complete AV dissociation consistent with third-degree (complete) AV block (Figure 1). Fetal cardiac function was preserved, without significant endocardial fibroelastosis or pericardial effusion. Given the acuity of the development of the AV block, the patient was treated immediately with 1 g/kg intravenous immunoglobulin (IVIG) and 8 mg/day dexamethasone. A follow-up fetal echocardiogram at 22 + 0 weeks showed improvement to first-degree AV block (Figure 2). The dexamethasone dose was tapered gradually to 2 mg/day by 30 weeks' gestation, and this dose was continued until delivery. In addition, 1-g/kg IVIG was administered every 4 weeks throughout the remainder of the pregnancy. At 38 + 5 weeks, the patient delivered a neonate with a birth weight of 3.3 kg. A postnatal electrocardiogram demonstrated normal sinus rhythm with a PR interval of 136 ms. The postnatal echocardiogram was normal. Given the prenatal course of treatment and family history, the neonate received a single dose of IVIG at 2 g/kg and was started on 2 mg/kg/day of prednisolone, with an outpatient steroid taper. During the taper, the infant developed elevated inflammatory markers, including troponin, prompting a more gradual taper. Steroids were ultimately able to be discontinued, with normalization of biomarker levels by 3 months of age. At 8 months of age, the infant remained in normal sinus rhythm with normal AV intervals. Written informed consent was obtained from the patient for the publication of data and images. Neonatal lupus erythematosus (NLE) is an acquired autoimmune condition caused by transplacental passage of maternal autoantibodies, primarily anti-Ro/SSA and, less commonly, anti-La/SSB. Over one-third of mothers of cardiac NLE infants are asymptomatic and lack a rheumatological diagnosis1, as in the presented case. Maternal antibodies can cause a range of fetal and/or neonatal complications, the most severe of which is complete AV block. Although NLE is associated with high morbidity and mortality2-4, there is a lack of consensus regarding optimal strategies for prevention, prenatal monitoring and treatment of this condition1, 5. The controversy stems, in part, due to uncertainty about whether advanced-degree AV block may be reversible if progression is identified in utero. At our institution, pregnant women with high-risk antibody titers are monitored with weekly fetal echocardiograms and provided with FHR monitors for home use. Since initiation of the home FHR monitoring program in 2013, three cases of advanced-degree AV block have been detected using this method. However, this is the only case in which progression from second- to third-degree AV block was acutely detected and aggressive treatment with IVIG and high-dose dexamethasone was initiated within 24 h. This strategy successfully restored fetal sinus rhythm, which was sustained postnatally. In light of the debate surrounding monitoring and treatment of anti-Ro pregnancies, this case is an exceptional but important contribution to the literature. It highlights the benefit of combining intensive fetal surveillance with prompt intervention for acutely evolving second- to third-degree AV block. Continued research is essential for risk stratification in this population, validation of our treatment approach and development of collaborative multidisciplinary consensus guidelines. The data that support the findings of this study are available from the corresponding author upon reasonable request.