Value of electron-beam computed tomography for the noninvasive detection of high-grade coronary-artery stenoses and occlusions

Background Reliable noninvasive assessment of coronary-artery stenoses and occlusions would constitute an advantage in the care of patients with known or suspected coronary artery disease. We investigated the accuracy of cont rast-enhanced electron-beam computed tomography (CT) for the detection of h igh-grade coronary-artery stenoses and occlusions. Methods Electron-beam CT was performed in 125 patients. After intravenous i njection of a contrast agent, 40 cross-sectional images of the heart were a cquired during inspiration, triggered by the electrocardiogram in diastole. Three-dimensional reconstructions of the heart and coronary arteries were rendered to facilitate evaluation of the images. The proximal and middle se gments of the major coronary arteries were evaluated for the presence or ab sence of high-grade stenoses and occlusions, The results were compared with those of invasive coronary angiography in a blinded fashion. Results Because of technical problems that impaired the quality of the imag es, 124 (25 percent) of the 500 coronary arteries studied (left main, left anterior descending, left circumflex, and right coronary) in a total of 125 patients were excluded from evaluation. No vessels could be evaluated in 1 9 patients (15 percent), and another 28 patients (22 percent) had one, two, or three vessels that could not be evaluated. In the remaining coronary ar teries with adequate image quality, electron-beam CT permitted visualizatio n of 69 of 75 high-grade stenoses and occlusions (sensitivity, 92 percent), whereas in 282 of 301 arteries, the absence of high-grade stenoses and occ lusions was correctly detected (specificity, 94 percent). Conclusions When image quality is adequate, electron-beam CT may be useful to detect or rule out high-grade coronary-artery stenoses and occlusions. ( N Engl J Med 1998;339:1964-71.) (C) 1998, Massachusetts Medical Society.