- The patient is a 3 year old female with a history of lung infections as an infant and diagnosis of congenital heart disease requiring surgery at age 1 year. - Examination found signs of right heart enlargement and a loud heart murmur. Echocardiogram showed a large ventricular septal defect with left-to-right shunting and mild pulmonary artery hypertension. - Cardiac catheterization was performed and found severe pulmonary artery hypertension with right ventricular and pulmonary artery pressures elevated. Oxygen saturations were low in the veins and pulmonary artery.