Surgical and Cardiac Catheterization Outcomes of Scimitar Syndrome Patients: A Three Decade Single-Center Experience.

Scimitar syndrome (SS) is a rare congenital condition which includes partial anomalous pulmonary venous return (PAPVR) and a variable degree of pulmonary hypoplasia. We describe the clinical features, therapeutic approach and outcomes of patients who underwent cardiac catheterization and/or surgical repair of the scimitar vein at a single institution in the United States. This retrospective cohort study included all patients with SS who underwent scimitar vein surgical repair or cardiac catheterization from October 1989 through August 2021 in a tertiary care center. A total of 84 patients with SS were included and median follow-up time was 74 months. Patients diagnosed with SS under the age of one year had a significantly greater incidence of congenital heart defects (CHD) (p < 0.001), non-cardiac anomalies (p = 0.02), pulmonary hypertension (p = 0.02), and mortality (p = 0.04) compared to those diagnosed over the age of 1 year. Twenty-eight patients underwent surgical repair of the scimitar vein. Overall, eight (10%) patients died. Compared to surviving patients, deceased patients had a significantly higher incidence of pulmonary hypertension (PH), neonatal SS diagnosis, and extracorporeal membrane oxygenation (ECMO) support. Median scimitar vein pressure (20 mmHg) of deceased patients was significantly higher compared to pressures in surviving patients (11 mmHg; p = 0.02). PH, CHD, neonatal SS diagnosis, ECMO support, and markedly elevated scimitar vein pressure are associated with mortality. Scimitar vein surgical repair during infancy is commonly associated with PH and restenosis that requires re-intervention.