OBJECTIVE The recent newer advances in computed tomography have dramatically changed our approach to imaging cardiac disease. This study sought to compare the diagnostic value of 16-multi-detector spiral computed tomography (MSCT) for detecting coronary artery stenosis. METHODS A total of 88 consecutive patients (52 men, mean age 68 +/- 8 years) with atypical chest pain, stable angina or suspicion of ischaemia at stress test were studied by MSCT and invasive coronary angiography (ICA). The MSCT images and multiplanar reconstructions were analysed regarding the presence of > or =50% coronary artery lesion. RESULTS All 88 scans obtained at a mean heart rate of 68 +/- 8 beats/min were interpretable. Sixteen coronary segments were evaluated in each patient. Of the 1320 segments examined, 148 (11%) showed poor image quality.A total of 150 significant lesions were detected using ICA, and 80 of 150 (53%) were detected by MSCT. Sensitivity, specificity, positive and negative predictive values were as follows: 53%, 97%, 68%, and 94%. Fifty-four patients had > or =50% coronary stenosis. The diagnosis was confirmed by MSCT in 42 patients and correctly ruled out in 30. By patient-based analysis, positive and negative predictive values were 91% and 71%. CONCLUSIONS Although its specificity is high, the sensitivity of 16-slice MSCT for detecting > or =50% coronary stenosis in non-selected patients submitted to ICA is rather low suggesting that for daily practice the diagnostic value of this technique should be improved.