Isolated coronary ostial stenosis associated with coronary vasospasm

A 50-year-old woman was brought to the emergency room in a preshock condition. An emergency coronary angiogram revealed 90% ostial stenosis of the left coronary artery with delayed distal filling. After intracoronary nitrate, the degree of stenosis was reduced to 75%; no other coronary lesions were evident. The patient was found to have hyperthyroidism and she became euthyroid after a 2-month regimen of methimazole. A follow-up coronary angiogram showed that the left coronary artery had 50% ostial stenosis without delayed distal filling. At the same time, an aortogram showed complete occlusion of the right subclavian artery in its proximal site, a slight dilatation of the truncus brachiocephalic artery, and a diffuse wall irregularity of the abdominal aorta, suggestive of Takayasu's arteritis.