Comparative study of dobutamine stress electron-beam computed tomography and exercise thallium scintigraphy in the diagnosis of patients with suspected coronary artery disease.

To evaluate the diagnostic value of dobutamine stress electron-beam computed tomography (EBCT) as compared with exercise stress thallium-201 single-photon emission computed tomography (201T1-SPECT) for the detection of myocardial ischemia, 10 patients with proven or suspected coronary artery disease underwent both tests. Nine of the 10 patients also underwent coronary angiography. EBCT images were analyzed objectively to evaluate systolic wall thickening and analyzed segmentally to determine the distribution of the coronary arteries. Dobutamine stress EBCT revealed the presence of ischemia in 59 segments, whereas exercise stress 201T1-SPECT revealed ischemia in 51 segments (agreement = 73%). The advantage of dobutamine stress EBCT was demonstrated in the inferior/posterior segments as compared with the results of exercise stress 201T1-SPECT. The overall sensitivity for detecting ischemic regions supplied by coronary arteries with significant stenosis (diameter stenosis > 50%) was 83% for dobutamine stress EBCT and 79% for exercise stress 201T1-SPECT (p = NS), with specificities of 75% and 82% (p = NS). Thus, dobutamine stress EBCT presents a reasonable alternative to exercise stress 201T1-SPECT for the objective assessment of patients with suspected coronary artery disease.