Detection of coronary artery stenoses with thin-slice multi-detector row spiral computed tomography and multiplanar reconstruction

Background-We analyzed the accuracy of multi-detector row spiral computed tomography (MDCT) using a 16-slice CT scanner with improved spatial and temporal resolution, as well as routine premedication with beta-blockers for detection of coronary stenoses. Methods and Results-Seventy-seven patients with suspected coronary disease were studied by MDCT (12x0.75-mm cross-sections, 420 ms rotation, 100 mL contrast agent IV at 5 mL/s). Patients with a heart rate above 60/min received 50 mg atenolol before the scan. In axial MDCT images and multiplanar reconstructions, all coronary arteries and side branches with a diameter of 1.5 mm or more were assessed for the presence of stenoses exceeding 50% diameter reduction. In comparison to invasive coronary angiography, MDCT correctly classified 35 of 41 patients (85%) as having at least 1 coronary stenosis and correctly detected 57 of 78 coronary lesions (73%). After excluding 38 of 308 coronary arteries (left main, left anterior descending, left circumflex, and right coronary artery in 77 patients) classified as unevaluable by MDCT (12%), 57 of 62 lesions were detected, and absence of stenosis was correctly identified in 194 of 208 arteries (sensitivity: 92%; specificity: 93%; accuracy: 93%; positive and negative predictive values: 79% and 97%). Conclusions-MDCT coronary angiography with improved spatial resolution and premedication with oral beta-blockade permits detection of coronary artery stenoses with high accuracy and a low rate of unevaluable arteries.