Clinical characteristics and outcomes in pregnant women with Ebstein anomaly at the time of delivery in the USA: 2003-2012.

Background: Ebstein anomaly is an uncommon congenital cardiac lesion that may be associated with cyanosis, arrhythmias and right heart dysfunction. Investigation into patient characteristics and outcomes in pregnant women with Ebstein anomaly has been limited.

Aims: To characterize patient characteristics and clinical events for pregnant women with Ebstein anomaly during hospitalization for delivery in the USA; also, to determine the effect of Ebstein anomaly on maternal clinical outcomes and individual predictors of poor outcome at time of delivery.

Methods: We screened the Healthcare Cost and Utilization Project's National Inpatient Sample for hospital admissions of pregnant women for delivery (vaginal or caesarean section) in the USA from 2003-2012, and identified a cohort of 7,850,381. Clinical characteristics and maternal outcomes were identified in those with and without Ebstein anomaly. The primary outcome of interest was major adverse cardiac events (MACE), a composite of in-hospital death, acute myocardial infarction, cerebrovascular events, embolic events, cardiac complications of labour and delivery heart failure or arrhythmia.

Results: Our study population consisted of 82 hospitalizations of pregnant women with Ebstein anomaly and 7,850,299 without. The Ebstein cohort more frequently had ostium secundum-type atrial septal defect and/or patent foramen ovale and anomalous atrioventricular excitation (P<0.001 for both). The MACE rate was significantly higher among Ebstein patients (P<0.001). Preterm delivery, postpartum haemorrhage and caesarean delivery occurred more frequently among the Ebstein cohort (19.5% vs 7.2%, 8.5% vs 2.8% and 47.6% vs 31.1%, respectively; P≤0.001). In a multivariable analysis, anomalous atrioventricular excitation (odds ratio [OR] 21.75, 95% confidence interval [CI] 1.03-457.91) and preterm delivery (OR 11.71, 95% CI 1.39-98.89) were associated with MACE among those with Ebstein anomaly.

Conclusions: Pregnant women with Ebstein anomaly are at higher risk of MACE during pregnancy and delivery. Preterm delivery occurred more frequently in women with Ebstein anomaly.