Discordance between thallium-201 scintigraphy and coronary angiography in patients with Kawasaki disease: myocardial ischemia with normal coronary angiogram

To assess the usefulness of radionuclide tests in detecting coronary occlusive lesions in children with Kawasaki disease, we compared the results of stress thallium-201 myocardial single photon emission computed tomography with dipyridamole infusion and coronary angiography in 34 patients (19 males and 15 females). Perfusion defects on the stress image only were categorized as transient and were attributed to coronary vascular disease in the presence of redistribution on the delayed image. Others were classified as persistent, due to myocardial damage. Five of the seven children (71%) with severe stenosis on coronary angiography showed persistent and/or transient perfusion defects. However, six of the 11 children (55%) with aneurysms but no obvious stenosis, and four of the 16 children (25%) with normal angiography, showed persistent and/or transient defects. After analyzing 20 individual segments of perfusion defects in the 15 children, six segments (30%) were attributed to the stenosis of supplying coronary arteries, six segments (30%) were related to the coronary aneurysms, and eight segments (40%) were unrelated to any abnormalities on angiography. Thus, significant discordance between the radionuclide and angiographic studies was demonstrated. These results suggest that coronary lesions, as conventionally defined by angiography and supplemented by echocardiography, may not completely identify all Kawasaki patients who may develop myocardial ischemia in the future or who had ischemia in the past.