Assessment of fluorinated steroids to avert progression and mortality in anti-SSA/Ro-associated cardiac injury limited to the fetal conduction system

OBJECTIVES

Extension of disease beyond the atrioventricular (AV) node is associated with increased mortality in cardiac neonatal lupus (NL). Treatment of isolated heart block with fluorinated steroids to prevent disease progression has been considered but published data are limited and discordant regarding efficacy. This study evaluated whether fluorinated steroids given to manage isolated advanced block prevented development of disease beyond the AV node and conferred a survival benefit.

METHODS

In this retrospective study of cases enrolled in the Research Registry for NL, inclusion was restricted to anti-SSA/Ro-exposed cases presenting with isolated advanced heart block in utero who either received fluorinated steroids within 1 week of detection (N=71) or no treatment (N=85). Outcomes evaluated were: development of endocardial fibroelastosis, dilated cardiomyopathy and/or hydrops fetalis; mortality and pacemaker implantation.

RESULTS

In Cox proportional hazards regression analyses, fluorinated steroids did not significantly prevent development of disease beyond the AV node (adjusted HR=0.90; 95% CI 0.43 to 1.85; p=0.77), reduce mortality (HR=1.63; 95% CI 0.43 to 6.14; p=0.47) or forestall/prevent pacemaker implantation (HR=0.87; 95% CI 0.57 to 1.33; p=0.53). No risk factors for development of disease beyond the AV node were identified.

CONCLUSIONS

These data do not provide evidence to support the use of fluorinated steroids to prevent disease progression or death in cases presenting with isolated heart block.

Maternal and fetal factors associated with mortality and morbidity in a multi-racial/ethnic registry of anti-SSA/Ro-associated cardiac neonatal lupus

BACKGROUND

Cardiac manifestations of neonatal lupus include conduction disease and, rarely, an isolated cardiomyopathy. This study was initiated to determine the mortality and morbidity of cardiac neonatal lupus and associated risk factors in a multi-racial/ethnic US-based registry to provide insights into the pathogenesis of antibody-mediated injury and data for counseling.

METHODS AND RESULTS

Three hundred twenty-five offspring exposed to maternal anti-SSA/Ro antibodies with cardiac neonatal lupus met entry criteria. Maternal, fetal echocardiographic, and neonatal risk factors were assessed for association with mortality. Fifty-seven (17.5%) died, 30% in utero. The probability of in utero death was 6%. The cumulative probability of survival at 10 years for a child born alive was 86%. Fetal echocardiographic risk factors associated with increased mortality in a multivariable analysis of all cases included hydrops and endocardial fibroelastosis. Significant predictors of in utero death were hydrops and earlier diagnosis, and of postnatal death were hydrops, endocardial fibroelastosis, and lower ventricular rate. Isolated heart block was associated with a 7.8% case fatality rate, whereas the concomitant presence of dilated cardiomyopathy or endocardial fibroelastosis quadrupled the case fatality rate. There was a significantly higher case fatality rate in minorities compared with whites, who were at a lower risk of hydrops and endocardial fibroelastosis. Pacing was required in 70%; cardiac transplantation was required in 4 children.

CONCLUSION

Nearly one fifth of fetuses who develop cardiac neonatal lupus die of complications predicted by echocardiographic abnormalities consistent with antibody-associated disease beyond the atrioventricular node. The disparity in outcomes observed between minorities and whites warrants further investigation.