Complications related to pulmonary artery stenting include stent migration, jailing of vessels, vessel rupture, and compression of surrounding structures. Compression of the left main coronary artery (LMCA) as a result of stent placement in the right pulmonary artery (RPA) is extremely rare. We present two patients post repair of congenital heart disease who suffered LMCA compression following RPA stenting. The first patient experienced acute coronary insufficiency in the cardiac catheterization laboratory, whereas the second patient had a more chronic course. We also present a third patient who had a CT angiogram that demonstrated a close spatial relationship between the RPA and the LMCA. Based on our previous experiences, we felt that this patient was at significant risk for LMCA compression if the RPA were stented. Coronary compression is rare complication of pulmonary artery stenting but should be considered in cases with history of repaired congenital heart disease.