Right pulmonary artery thrombosis after hybrid stage 1 palliation: resolution after direct tissue plasminogen activator infusion.

A patient with unbalanced right ventricular dominant atrioventricular septal defect with ascending and transverse arch hypoplasia underwent hybrid stage 1 palliation. On postoperative day 7, he experienced irritability and acute cyanosis. Echocardiography demonstrated a thrombus occluding the right pulmonary artery band. Emergency cardiac catheterization confirmed thrombosis of the right pulmonary artery at the site of the band. Direct infusion of tissue plasminogen activator successfully lysed the thrombus.