Coronary artery to pulmonary artery collaterals in nonspecific aortoarteritis involving the pulmonary arteries.

We report a patient with nonspecific aortoarteritis (Takayasu's disease) in whom occlusion of the right upper lobe pulmonary artery was associated with collateral flow from the left circumflex coronary artery. Coronary to pulmonary artery collaterals are rare in this disease but have important clinical implication because of their ability to produce coronary steal and myocardial ischemia. Awareness of these pathways is essential for their detection in patients with angina-like symptoms and for differentiation of myocardial ischemia due to direct coronary artery involvement by this disease.