To Be or Not to Be Eisenmenger: The Different Shades of Blue.

Eisenmenger syndrome refers to any untreated congenital cardiac defect with an intracardiac communication that leads to pulmonary arterial hypertension, reversal of intracardiac shunting, and cyanosis. We describe a 40-year-old cyanotic patient with congenital heart disease with presumed Eisenmenger syndrome who was considered inoperable. Testing revealed a partial atrioventricular septal defect with no evidence of pulmonary arterial hypertension, and the patient underwent successful cardiac repair. (Level of Difficulty: Intermediate.).