Influence of SPECT-CT attenuation correction on the diagnostic performance for coronary disease. Correlation with coronary angiography and visual analysis

Introduction: The aim was to assess the diagnostic performance of SPECT-CT versus studies without attenuation correction (S -AC) by visual analysis and correlation with coronary angiography. Materials and methods: Twenty patients (16 men 62 ± 8.4 years) were retrospectively evaluated referred for chest pain who had SPECT and coronary angiography (± 3 weeks). Two observers reported images of S-AC and AC. The correlation of the 20 patients was performed by vessel (ADA, Cx and RCA) for a total of 60 vessels evaluated. Estimates of sensitivity (S), specificity (E), positive predictive value (PPV) and negative predictive value (NPV) considering significant obstruction coronary ≤70 % and significant ischemia ≥5 % by territory were performed. Other variables measured: Weight, height, sex, body mass index (BMI). Results: Twenty percent of angiographies were normal or had no significant obstruction. As per the results of the 60 vessels evaluated by coronary angiography, CT-AC images showed S: 88% (NS) and E: 75% (p 0.0073), and S-AC S: 88% and E: 50%. The PPV and NPV was 93% and 60% for CT- AC and 88% and 50% for S-AC. The right coronary artery presented E: 78% (p: 0.003) for AC images versus 65% for S-AC. Conclusion: Images with CT-AC showed higher specificity than S-AC images. AC had better specificity in detecting stenosis of the right coronary artery