Twin pregnancy complicated by total placenta previa in a Fontan-palliated patient: A case report.

We present a case of a twin pregnancy in a Fontan-palliated woman that was complicated by total placenta previa. The patient was diagnosed with tricuspid atresia type II, and underwent the Fontan operation at 11 years of age. At 32 years of age, she was shown to have a dichorionic diamniotic twin pregnancy. A placenta previa was also noted. At 26 weeks' gestation, she had difficulty breathing, cardiomegaly, and worsening mitral regurgitation. At 29 weeks' gestation, an emergency cesarean section was performed, as the patient had massive genital bleeding. A postoperative cardiac catheterization demonstrated a leak from the lateral tunnel to the atrium, which was considered a cause of hypoxemia during the peripartum period. The cardiac workload in a twin pregnancy is greater, which places a Fontan-palliated patient at increased risk. Careful follow-up monitoring with multidisciplinary expertise is recommended.