Pediatric/Adult Congenital Heart Disease -> Adult Congenital Heart Disease D-AB31 - ACHD and Pediatric EP (ID 29) Abstract

D-AB31-03 - Arrhythmia Outcomes In Pregnant Women With Adult Congenital Heart Disease (ID 777)


Background: Arrhythmias are common in adult congenital heart disease (ACHD) and are associated with worse prognosis. While arrhythmias can increase, the epidemiology and prognostic implications of arrhythmias in pregnant ACHD patients remains poorly characterized.
Objective: To characterize arrhythmia outcomes in pregnant ACHD patients.
Methods: We conducted a retrospective observational analysis of women with ACHD treated at the University of Washington between 2010 and 2019. Arrhythmias were managed per standard clinical care. Cardiovascular outcomes including supraventricular and ventricular arrhythmia, heart failure, and death were assessed.
Results: At total of 212 pregnancies in 171 women (mean age 28.7 +/- 5.8 years, range 18-43 years); were followed (gravity 2.4 +/- 2). Prior to pregnancy, 18% (n=38) of patients had a history of arrhythmia, and11 had CIEDs. 23% had simple ACHD anatomy, 68.4% had moderate and 8.5% were characterized as complex. When compared to patients without a history of arrhythmias, those with pre-pregnancy arrhythmias were significantly more likely to have concomitant diagnoses of anxiety (32% v. 10%, p<0.001) and heart failure (11% v. 3%, p=0.03), and were also more likely to have arrhythmias during pregnancy (34% v. 2%, P<0.001). Infants born to mothers with arrhythmias pre-pregnancy (74% of whom were on beta blockers or antiarrhythmics) had a more than 2-fold increased odds of requiring neonatal ICU (42% v. 24%, OR 2.4, p-0.0217). There were no maternal deaths and no fetal deaths, although the referral bias of this quaternary care center database may have underestimated the prevalence of early fetal losses.
Conclusion: Arrhythmias are common in this cohort of women with ACHD prior to pregnancy and associated with both heart failure and an anxiety diagnosis. Incident arrhythmias, however, are relatively rare during pregnancy in women with ACHD. The presence of pre-pregnancy arrhythmias is highly associated with arrhythmias during pregnancy which, in turn, was associated with worse fetal outcomes. Further study is needed to refine best practices in this heterogenous and growing population.