Cardiac and Perinatal Outcomes Among Pregnancies With Maternal Cardiac Arrhythmias

Atrial fibrillation/flutter (AF/AFL) and supraventricular tachycardia (SVT) are common arrhythmias in pregnancy. While known to contribute to adverse outcomes, large studies have not evaluated cardiac and perinatal outcomes in patients with arrhythmias. The objective of this study is to compare the cardiac/perinatal outcomes of pregnant patients with AF/AFL and SVT in pregnancy versus those without arrhythmias. We performed a retrospective cohort study utilizing Epic Cosmos, a dataset from 1,500 US hospitals. We identified pregnancies between October 25, 2021, and October 24, 2024, of patients with a diagnosis of AF/AFL and SVT using simultaneous diagnoses codes for each arrhythmia and pregnancy. A control group of pregnancies without arrhythmias was also identified. Descriptive statistics were calculated, and comparisons were made with ANOVA or Chi-square tests, as appropriate. During the study period, there were 8,642 pregnant patients with AF/AFL, 29,638 with SVT, and 5,372,171 healthy pregnant controls. Patients with these arrhythmias were older (AF/AFL: 33 ± 6, SVT: 32 ± 6, control: 31 ± 6, p < 0.0001) with a higher body mass index than the control group. Those with arrhythmias experienced higher rates of heart failure (AF/AFL: 11%, SVT: 4%, control: 0.3%), thromboembolism, stroke, preterm birth, and cesarean delivery (all p < 0.0001). Patients with AF/AFL had 24 times higher odds of stroke compared to the control group (95% CI 21 to 27). In conclusion, while both AF/AFL and SVT are associated with adverse outcomes, AF/AFL had a higher association with heart failure and stroke in the perinatal period, and further research is need to understand optimal perinatal AF/AFL management, especially anticoagulation therapy.