Abstract:Aim To explore the value of adenosine triphosphate (ATP) stress 99mTc-Methoxyisobutylisonitri(99mTc-MIBI) gated myocardial single-photon tomography (SPECT) imaging for making risk stratificatioin in the patients with intermediate coronary lesions. Methods In this study, 100 patients with intermediate coronary lesions, diagnosed by coronary angiography (CAG) were involved. The short axis and vertical long axis slices of left ventricular myocardial were divided into 17 segments by ATP stress 99mTc-MIBI gated myocardial SPECT examination. We evaluated radionuclide distribution of each segment sections of left ventricular myocardium with semiquantitative visual method, calculated summed stress score (SSS), summed rest score (SRS), summed difference score (SDS), and ischemia segment number of left ventricular, analyzed the severity myocardial ischemia, and made risk stratificatioin, compared with the severity and vessel narrowness of intermediate coronary lesions. Results A total of 100 patients with intermediate coronary lesions were enrolled in this study, including 62 patients with single intermediate coronary lesion, 33 patients with double-vessel lesions, and 5 patients with three. The risk stratification of patients with intermediate coronary lesions was divided into 45 cases (45.0%) in low risk group, 34 cases in middle risk group (34.0%) and 21 cases in high risk group (21.0%). The proportion of high-risk patients in multi-vessel disease group was higher, SSS and SDS were higher than those in single-vessel disease group. And there were significant differences of SSS and SDS between the two groups (P<0.05), but there was no significant difference of SRS (P>0.05). All patients had a total of 143 intermediate coronary lesions, including 84 LADs, 29 LCXs, 30 RCAs. SSS, SDS, SRS were not significantly different between the three groups (P>0.05). There was no significant difference in risk stratificatioin between patients with mild stenosis and moderate stenosis. Narrowness has no correlation with SSS, SRS and SDS in all intermediate coronary lesions regardless LAD, LCX or RCA. The result of ATP stress 99mTc-MIBI gated myocardial SPECT was significantly higher than that in dynamic electrocardiogram (76.0% vs 39.0%, P<0.05). Conclusion ATP stress 99mTc-MIBI myocardial SPECT imaging could make risk stratification more precisely in the patients with intermediate coronary artery lesions, and guide clinical treatment.