Causes of fetal third-degree atrioventricular block and use of hydroxychloroquine in pregnant women with Ro/La antibodies

Treatment options for preventing autoimmune-mediated congenital heart block: a systematic review

OBJECTIVE

Complete congenital heart block (CHB) due to anti-Ro/La antibodies in pregnancy can lead to adverse fetal outcomes and neonatal death. National and international guidelines do not recommend specific treatment for women identified with anti-Ro antibodies while pregnant.

DESIGN

Systematic review of studies of pregnant women with anti-Ro/La antibodies undertaking treatment(s) to prevent CHB. Studies solely focused on treating developing or established CHB were excluded.

MAIN OUTCOME MEASURE

CHB incidence.

RESULTS

Of 1049 articles, 20 studies were eligible, of which 13 were retrospective. Sixteen studies contained usable data comparing various treatments (seven hydroxychloroquine (HCQ), six corticosteroids, two intravenous immunoglobulin (IVIG) and one each on combined HCQ and corticosteroids and plasmapheresis), including 2134 women and 2915 pregnancies. Meta-analysis was not possible due to heterogeneity. HCQ as primary prophylaxis showed protective effect on CHB incidence in four of five studies, whereas for preventing recurrence, only one study had a comparator arm, which showed a protective effect. Corticosteroids showed protective effect on CHB incidence as primary prophylaxis in two of three studies, whereas in recurrence, only one study showed protective effect. The IVIG study with a comparator showed no protective effect on CHB recurrence. Two studies (IVIG and plasmapheresis) had no comparator. The long-term toxicity of treatments was poorly investigated.

CONCLUSION

HCQ showed the most evidence among various treatment options to prevent CHB in babies of women with anti-Ro/La antibodies. However, included studies had high risk of bias and imprecision. Future studies should be prospective, compare existing treatments and capture adverse effects.PROSPERO registration number CRD42023492934.

"An update on the approach to treatment of Sjogren's Disease in pregnancy"

BACKGROUND

Women with Sjögren's Disease are more likely to experience pregnancy complications compared to their counterparts without the disease. Attention to detail and familiarity with the most recent research and guidelines in this field are required to achieve optimal maternal and fetal outcomes. Such complications include pregnancy induced hypertension, fetal growth restriction, thromboembolic events, and preterm delivery. Among the most life-threatening sequela of maternal Sjogren's Disease is fetal autoimmune congenital heart block (ACHB), which has high potential to cause intrauterine fetal death, neonatal mortality, developmental delay, and other long-term pediatric complications. Currently, surveillance with weekly echocardiograms and obstetric sonograms in the second trimester are recommended to screen for ACHB with the goal of early detection and intervention before progression from first- or second- of heart block to complete heart block.

OBJECTIVE

We describe a case of maternal Sjogren's Disease, which prompted us to raise questions regarding the optimal frequency of obtaining fetal echocardiograms, and the ideal management in case a prolonged PR interval was to be found. We use this case to provide a springboard for discussion on updated antenatal management strategies for ACHB prevention.

METHODS

To conduct this analysis, we searched PubMed for articles published over the last 10 years, with attention focused on articles written since 2016. Additionally, updated guidelines by other specialties such as Rheumatology, Cardiology and Pediatrics on this issue were reviewed.

RESULTS

Thorough search of the literature yielded several meta-analyses concurring that the mothers with Sjogren's Disease had increased rates of premature birth, pregnancy induced hypertension, increased risks of delivering infants with intrauterine growth restriction (IUGR), with the most life-threatening risk being that of congenital heart block. Literature supporting prophylactic hydroxychloroquine and the use of steroids to reverse or halt the progression of congenital heart block at the time of diagnoses appeared at the forefront of search results.

CONCLUSION

Pregnant women with SS have an increased risk for complications such as intrauterine growth restriction, thromboembolic events, pregnancy-induced hypertension, preterm delivery, and cesarean delivery and should prioritize obtaining pre- or peri-conceptional counseling. In women with anti SSA/SSB antibodies, a medication regimen should be considered with the object of decreasing the concentration of these antibodies, and hence decrease the risks of ACHB. Current literature supports the inclusion of hydroxychloroquine for this purpose, even prior to conception. Although the most recent studies recommend against prophylactic use of steroids, their potential to prevent progression to complete block should be weighed against their potential negative effects. Short and long-term treatment with corticosteroids has been associated with increased maternal risk of infection, weight gain, osteonecrosis, hypertension and bone mineral density disorders. Intrauterine growth restriction, oligohydramnios, and adrenal suppression have been among the fetal risks associated with steroids while improved infant survival or decreased need for pacing have not been demonstrated. Management of these pregnancies is complex and should include a multidisciplinary approach involving a maternal-fetal medicine sub-specialist, a rheumatologist, a pediatrician, a neonatologist, and the patient herself with her family in a model of shared decision-making.

Hydroxychloroquine and the associated risk of arrhythmias

Hydroxychloroquine (HCQ), which was initially used as an antimalarial drug, is now being used to treat other illnesses, especially rheumatic autoimmune disorders  such as systemic lupus erythematosus, primary Sjögren's syndrome, and rheumatoid arthritis, because it is safe, effective, and cost efficient. This drug has shown high efficacy and has become the first-line treatment for many of these diseases. Although HCQ has many therapeutic effects, it has unfortunately shown some complications, especially with its long-term use. One of these side effects is arrhythmia through prolongation of the QT interval. This narrative literature review focuses on the effects of HCQ on the QT interval in patients with rheumatologic diseases who have been prescribed this drug. In particular, we will focus on the increased risk of arrhythmia when HCQ is administered with other drugs, such as azithromycin and many others, along with drug-drug interactions. In addition, we investigated the safety of this drug in pregnant women.

Autoimmune congenital heart block: a case report and review of the literature related to pathogenesis and pregnancy management

Autoimmune congenital heart block (ACHB) is a passively acquired immune-mediated disease characterized by the presence of maternal antibodies against components of the Ro/SSA and La/SSB ribonucleoprotein complex that mainly affects the cardiac conducting system. ACHB occurs in 2% of women with positive anti-Ro/SSA and anti-La/SSB antibodies and causes a high risk of intrauterine fetal death, neonatal mortality, and long-term sequelae. In this review, we first describe a case of ACHB to provide preliminary knowledge. Then, we discuss the possible pathogenic mechanisms of ACHB; summarize the pregnancy management of patients with positive anti-Ro/SSA and anti-La/SSB antibodies and/or rheumatic diseases, the prevention of ACHB, and the treatment of ACHB fetuses; and propose routine screening of these antibodies for the general population. Careful follow-up, which consists of monitoring the fetal heart rate, is feasible and reassuring for pregnant women with positive anti-Ro/SSA and/or anti-La/SSB antibodies to lower the risk of ACHB in fetuses. Moreover, maternal administration of hydroxychloroquine may be useful in preventing ACHB in pregnant women with anti-Ro/SSA and/or anti-La/SSB antibodies.

Pacemaker Management and In-Hospital Outcomes in Neonatal Congenital Atrioventricular Block

BACKGROUND

Neonatal congenital atrioventricular block (nCAVB) is rare, causes bradycardia, confers high mortality, and frequently requires pacing. In-hospital outcomes and pacemaker management in nCAVB are limited.

OBJECTIVES

The purpose of this study was to analyze pacing and outcomes of nCAVB with and without congenital heart disease (CHD) using a multicenter database.

METHODS

A Pediatric Health Information System database review from January 1, 2004, to June 30, 2022. Patients <31 days of age with a nCAVB International Classification of Diseases-9th/10th Revision diagnosis code and no cardiac surgeries except pacemaker were included. Pacing and in-hospital mortality were analyzed using univariate and multivariable logistic statistics and competing risk and event-free survival models.

RESULTS

Of 1,146 patients with nCAVB, 659 (57.5%) were girls and 506 (44.2%) were premature. Among the 326 (28.4%) with CHD, 134 (41.1%) underwent pacemaker insertion as initial intervention and 56 (17.2%) had temporary pacing wires. In-hospital mortality occurred in 118 (36.2%), with increased adjusted odds with temporary pacing wires placed at 0 to 1 or 2 to 7 days of age relative to no wires, and with decreased odds among pacemakers placed at 2 to 7 or 8+ days of age relative to no pacemaker. Of 820 (71.6%) without CHD, 334 (40.7%) underwent pacemaker insertion as the initial intervention and 81 (9.9%) had temporary pacing wires. In-hospital mortality occurred in 69 (8.4%) with increased adjusted odds in prematurity and decreased odds among pacemaker placement at 2 to 7 days of age relative to no pacemaker.

CONCLUSIONS

Over 18.5 years, in-hospital mortality occurred in 36.2% of nCAVB patients with CHD and 8.4% with non-CHD. Associations with increased in-hospital mortality included CHD and prematurity and decreased with pacemaker placement. Prospective registries are needed to better characterize and standardize management of this rare but high-mortality disease.

Reversal of Fetal Heart Block in Antibody-Positive Mother After Hydroxychloroquine and Dexamethasone

Maternal autoantibody-related complete heart block in the fetus is considered irreversible. During prenatal care for a 25-year-old nulliparous Hispanic woman with newly diagnosed nephrotic-range proteinuria and positive anti-nuclear antigen antibody, complete fetal heart block with a ventricular rate of 60 beats per minute was detected on a fetal echocardiogram at 28-week gestation. A small pericardial effusion and ascites were noted consistent with fetal hydrops. Dexamethasone and hydroxychloroquine were initiated. Fetal rhythm improved to Mobitz type 1 second-degree heart block, with a ventricular rate of 91 beats per minute. The fetus was born prematurely at 34-week gestation with second-degree heart block which improved to first-degree heart block prior to hospital discharge. First-degree heart block persisted at 2 years of age with a P-R interval of 185 ms. Transplacental treatment with dexamethasone and hydroxychloroquine was associated with sustained reversal of complete heart block to sinus rhythm.

Whole-Exome Sequencing Identifies a Novel TRPM4 Mutation in a Chinese Family with Atrioventricular Block

Atrioventricular block (AVB) is a leading cause of sudden cardiac death, and most of AVB cases are presented as autosomal dominant. The electrocardiogram of AVB patients presents an abnormal progressive cardiac conduction disorder between atria and ventricles. Transient receptor potential melastatin 4 (TRPM4) is a nonselective Ca²⁺-activated cation channel gene defined as a novel disease-causing gene of AVB. So far, 47 mutations of TRPM4 have been recorded in Human Gene Mutation Database. The aim of this study was to explore the relationship between TRPM4 mutation and pathogenesis of AVB. We investigated a Chinese family with AVB by whole-exome sequencing. An arrhythmia-related gene filtering strategy was used to analyze the disease-causing mutations. Three different bioinformatics programs were used to predict the effects of the mutation result. A novel mutation of TRPM4 was identified (c.2455C>T/p.R819C) and cosegregated in the affected family members. The three bioinformatics programs predicted that the novel mutation may lead to damage. Our study will contribute to expand the spectrum of TRPM4 mutations and supply accurate genetic testing information for further research and the clinical therapy of AVB.

Causes of fetal third-degree atrioventricular block and use of hydroxychloroquine in pregnant women with Ro/La antibodies

INTRODUCTION/OBJECTIVES

Complete congenital atrioventricular block (AVB) may be due to cardiac malformations or the presence of maternal antibodies (autoimmune AVB). Our objective was to estimate the prevalence of autoimmune AVB among all AVB in newborns treated at our hospital. Secondly, we estimated the prevalence of AVB among mothers with anti-Ro/La antibodies and examined the relationship of those fetal AVB with mother's use of hydroxychloroquine during pregnancy.

METHODS

Retrospective cohort in which we reviewed electronic medical records from years 2000 to 2014 of (a) all mothers with children born with third degree AVB and (b) all pregnant women with anti-Ro/La-positive antibodies.

RESULTS

Twenty-three AVBs were diagnosed. Ten (43.5%, 95% CI 23.2-65.5) were associated with maternal rheumatologic disease. The remaining 13 were associated with cardiac malformations. Sixty-two pregnancies in 47 mothers with Ro/La antibodies were identified; eight (12.9%, 95% CI 5.7-23.8) suffered AVB. Fourteen mothers consumed hydroxychloroquine during full pregnancy (one newborn (7.1%) suffered AVB) and 48 did not (7 newborns with AVB (14.6%); p = 0.5).

CONCLUSIONS

All congenital AVB diagnosed at our hospital without cardiac malformations were associated with a maternal rheumatologic disease/antibodies. Therefore, if a AVB is diagnosed in a newborn without structural heart disease, the mother should be studied for an autoimmune disease. We found a high prevalence of AVB among mothers with anti-Ro/La antibodies. Although not statistically significant, AVBs in mothers with Ro/La antibodies were numerically more frequent in those not using hydroxychloroquine.Key Points• Although structural heart malformations were the predominant cause of third-degree AVB, autoimmune AVB was still a significant cause.• The distinction between structural or non-structural cause of AVB constitutes an essential issue since it determines the prognostic of these fetuses in terms of complications.• Although not statistically significant, AVBs in mothers with Ro/La antibodies were more frequent in those not using hydroxychloroquine.• If an AVB is diagnosed in a newborn without structural heart disease, the mother should be studied for an autoimmune disease.