This patient with Eisenmenger syndrome has symptomatic relative anemia, and short-course iron therapy should be initiated. Most patients with cyanosis have compensated erythrocytosis with stable hemoglobin levels. Iron deficiency and resultant microcytosis in patients with cyanosis are often caused by unnecessary phlebotomy or blood loss. Microcytes are more rigid than normal erythrocytes; thus, microcytosis increases the risk of stroke. The treatment of iron deficiency is challenging. Oral iron often causes a rapid and dramatic increase in erythrocyte mass. Therefore, administration of 1 tablet daily of ferrous sulfate or ferrous gluconate is recommended, with repeat hemoglobin assessment in 7 to 10 days. This patient's usual hemoglobin level would be in the range of 18 g/dL (180 g/L). He developed perioperative anemia that has persisted and caused dyspnea and fatigue. Once the hemoglobin and hematocrit levels begin to increase, iron therapy can be discontinued. Erythrocyte transfusion is considered only for severe symptoms.

Erythropoietin is used in patients with anemia related to kidney disease and some malignancies but is not recommended for patients with heart disease and cyanosis who develop postoperative anemia.

Data are limited regarding the efficacy of epoprostenol in patients with Eisenmenger syndrome and pulmonary hypertension. When used, oral, subcutaneous, and inhaled therapies are preferred. Intravenous epoprostenol is typically avoided because of the risk for paradoxical embolism with continuous intravenous therapy in patients with an intracardiac right-to-left shunt.

Although heart-lung transplantation is an option for end-stage cardiopulmonary disease in patients with Eisenmenger syndrome, this option is not indicated without further trial of standard medical therapy with iron.