Atrial fibrillation with rapid ventricular response as a maternal presentation of mirror syndrome: a case report.

Mirror syndrome is the phenomenon of fetal hydrops causing maternal edema and weight gain. Here, we report a case of arrhythmia as the primary maternal symptom. A 36-year-old woman, G2P1001, at 34.5 weeks of gestation presented with new-onset fetal hydrops combined with maternal weight gain and edema. She developed atrial fibrillation with rapid ventricular response; cardiac workup was unremarkable. Rate control was achieved with diltiazem. She underwent delivery and reverted to normal sinus rhythm on post-operative day 1. Volume overload causes atrial wall stress and neurohormonal changes that may trigger atrial fibrillation. Optimization with rate control facilitated good maternal and fetal outcomes in this case.