Environmental and lifestyle factors influencing risk of congenital heart block during pregnancy in anti-Ro/SSA-positive women

A 1-year review of anti-Ro/La autoantibody testing in an obstetric population

OBJECTIVES

To evaluate current anti-Ro and anti-La autoantibody ordering patterns, clinical indications for performing these tests, and potential cost-benefit analysis.

METHODS

In this retrospective cohort study, patients who underwent autoantibody testing over 1 year were included. Necessary information was obtained from patient electronic records.

RESULTS

In total 47 patients underwent anti-Ro/La autoantibody testing. Of those tested, 11/47 (2%) had positive results and testing was clinically indicated in 26/47 (55%) patients, indicating minimal cost-benefits. The total rate of the cost prescription was €1644.96. The mean time to process tests was 5 days. In those with positive autoantibodies, two infants were diagnosed with congenital heart block and had pacemakers inserted after delivery.

CONCLUSION

This study found anti-Ro/La autoantibody tests were appropriately ordered in accordance with clinical guidelines. By identifying patients who were autoantibody negative, economic benefits were gained, in terms of antenatal management including reduced frequency of antenatal visits and fetal heart surveillance.

Unintended pregnancy-related factors and the occurrence of offspring congenital heart disease: a multi-site case-control study in China

OBJECTIVES

The aim of this study was to explore the association between unintended pregnancy and related factors among congenital heart defects (CHDs) in infants.

METHODS

A total of 1197 cases with isolated CHDs and 1125 controls without any abnormalities were analysed in this multicentre study at seven hospitals in China. According to the pregnancy intention, cases were divided into two groups: planned and unintended pregnancies. The adjusted odds ratio (AOR) was calculated by logistic regression analysis to assess the association between unintended pregnancy and CHD occurrence. The time to prepare for pregnancy and the influencing factors were also compared in this article.

RESULTS

The risk for CHD occurrence was significantly associated with unintended pregnancy (AOR: 1.42; 95%CI: 1.16-1.73), which may increase the risks for each subtype of CHD occurrence. Risks such as parental smoking, housing renovation, accidental alcohol consumption, lack of health check-ups, and no folic acid supplementation before pregnancy were distributed differently among the planned and unintended pregnancy groups and were associated with CHD occurrence. However, there was no significant association between the duration of planned pregnancy and the risk of CHDs.

CONCLUSIONS

Unintended pregnancy increased the risk of CHDs in infants. This risk may be related to some known and unknown factors.

SYNOPSIS

Some unintended pregnancy related factors may increase the risk for foetal CHDs. The duration of planning pregnancy may not be associated with the risk of CHDs.

Interferons and innate immune activation in autoimmune congenital heart block

Autoimmune congenital heart block (CHB) may develop in foetuses of women carrying anti-Ro/SSA and La/SSB autoantibodies and is characterized by disruption of signal conduction at the atrioventricular (AV) node, resulting in partial or complete AV block. If not fatal in utero, complete CHB typically requires lifelong cardiac pacing. No treatment has so far been unequivocally demonstrated to prevent or treat autoimmune CHB, and the relatively low incidence (1%-5%) and recurrence (12%-16%) rates of second/third-degree AV block add to the complexity of managing pregnancies in women with anti-Ro/La antibodies. Altogether, a better understanding of events leading to development of autoimmune CHB is needed to improve surveillance and treatment strategies. In the past decade, studies have started to look beyond the role of maternal autoantibodies in disease pathogenesis to assess other contributing factors such as foetal genetics and, more recently, immune responses in foetuses and neonates of anti-Ro/La antibody-positive women. In this review, we provide an update on the epidemiology, clinical presentation and current treatment approaches of autoimmune CHB, summarize the previously proposed pathogenic mechanisms implicating maternal autoantibodies, and discuss the recent findings of type I interferon (IFN) and innate immune activation in foetuses with autoimmune CHB and in neonates of anti-Ro/La antibody-positive mothers, and how these may contribute to autoimmune CHB pathogenesis.

Comorbidity and long-term outcome in patients with congenital heart block and their siblings exposed to Ro/SSA autoantibodies in utero

OBJECTIVE

Congenital heart block (CHB) may develop in fetuses of Ro/SSA autoantibody-positive women. Given the rarity of CHB, information on comorbidity and complications later in life is difficult to systematically collect for large groups of patients. We therefore used nation-wide healthcare registers to investigate comorbidity and outcomes in patients with CHB and their siblings.

METHODS

Data from patients with CHB (n= 119) and their siblings (n= 128), all born to anti-Ro/SSA-positive mothers, and from matched healthy controls (n= 1,190) and their siblings (n= 1,071), were retrieved from the Swedish National Patient Register. Analyses were performed by Cox proportional hazard modelling.

RESULTS

Individuals with CHB had a significantly increased risk of cardiovascular comorbidity, with cardiomyopathy and/or heart failure observed in 20 (16.8%) patients versus 3 (0.3%) controls, yielding a HR of 70.0 (95% CI 20.8 to 235.4), and with a HR for cerebral infarction of 39.9 (95% CI 4.5 to 357.3). Patients with CHB also had a higher risk of infections. Pacemaker treatment was associated with a decreased risk of cerebral infarction but increased risks of cardiomyopathy/heart failure and infection. The risk of systemic connective tissue disorder was also increased in patients with CHB (HR 11.8, 95% CI 4.0 to 11.8), and both patients with CHB and their siblings had an increased risk to develop any of 15 common autoimmune conditions (HR 5.7, 95% CI 2.83 to 11.69 and 3.6, 95% CI 1.7 to 8.0, respectively).

CONCLUSIONS

The data indicate an increased risk of several cardiovascular, infectious and autoimmune diseases in patients with CHB, with the latter risk shared by their siblings.