Objective We have compared the uncorrected images of SPECT myocardial perfusion plus gated data with corrected images with X-rays in the management of coronary artery disease. Methods In 60 patients (p) a stress/rest-gated myocardial perfusion SPECT was performed with attenuation correction with a hybrid gammacamera. All patients underwent cardiac catheterization. 3 types of images were qualitatively evaluated: uncorrected stress/rest (NC), uncorrected stress/rest plus gated (NCG) and stress/rest corrected for attenuation with scatter correction (AC). McNemar's test was used to analyze the statistical differences in assessing the diagnostic accuracy of each type of images; p Results Fourteen p did not have significant lesions in the coronary arteries (NSL), 46 p showed lesions in coronary arteries: 29 in anterior descending, 26 in right coronary and 18 in circumflex. In right coronary territory, diagnostic accuracy as significantly higher on AC than on NC images (p Conclusions Attenuation correction with X-rays significantly improves diagnostic accuracy of uncorrected images and uncorrected images plus gated.