Long‐Term Cardiovascular Outcomes Following New‐Onset Arrhythmias During Pregnancy

ABSTRACT Background Arrhythmias during pregnancy are increasingly prevalent and associated with acute adverse cardiovascular outcomes, yet their long‐term cardiovascular implications remain poorly defined. To address this gap, we conducted a large population‐based study to evaluate 5‐year cardiovascular outcomes following incident arrhythmias during pregnancy. Methods Using TriNetX, we conducted a retrospective cohort study of pregnant individuals (≥18 years) admitted for delivery between 2015 and 2020. Patients with new‐onset arrhythmias during pregnancy were compared with those without arrhythmias. Outcomes included composite cardiovascular outcomes, incident heart failure (HF), cerebrovascular accident (CVA), and acute myocardial infarction (AMI). Propensity score matching (1:1) was used to adjust for demographic and clinical comorbidities. Results Among 886,732 deliveries, 8507 patients (0.9%) had incident arrhythmias. After matching, individuals with incident arrhythmias during pregnancy had higher 5‐year risks of composite cardiovascular outcomes (risk ratios [RR] 3.82), HF (RR 4.48), CVA (RR 2.04), and AMI (RR 4.80) (all P  < 0.01). Associations persisted across age strata, with particularly elevated risks among those ≥35 years. Conclusions This study, among the first to our knowledge to evaluate long‐term cardiovascular outcomes following incident arrhythmias during pregnancy, demonstrates a substantially increased 5‐year cardiovascular risk, underscoring the need for extended postpartum cardiovascular surveillance beyond routine follow‐up.