Noninvasive evaluation of myocardial ischemia in Kawasaki disease: comparison between dipyridamole stress thallium imaging and exercise stress testing.

The sensitivities of dipyridamole stress thallium 201 single photon emission computed tomography (SPECT) and treadmill exercise testing in the detection of myocardial ischemia were compared. Thirty-eight patients with Kawasaki disease and 11 age-matched controls participated in the study. Fifteen of the 38 patients with Kawasaki disease had marked coronary artery stenosis (> 75%) in at least one vessel. SPECT scans were obtained immediately after dipyridamole infusion and 4 hours later. The sensitivity of SPECT for detection of coronary stenosis was 80% (12/15), whereas that of treadmill exercise testing was only 33% (5/15) (p < 0.001). Although the sensitivity of SPECT significantly exceeded that of treadmill exercise testing among patients with coronary stenosis in only one vessel (p < 0.05), such benefits were not found for patients with stenosis in two or three vessels. These findings suggest that dipyridamole stress SPECT has a higher degree of sensitivity in the detection of myocardial ischemia than does treadmill exercise testing, especially for patients with single-vessel disease.