Diagnostic Accuracy of Gated-SPECT Myocardial Perfusion Imaging and Exercise Stress Test for Diagnosis of Coronary Artery Disease

Background and Objective: Accurate diagnosis of CAD using noninvasive procedures is of great importance. The aim of the study is to assess diagnostic accuracy of myocardial perfusion imaging and compare it with exercise stress test in order to decipher a more accurate and cost-effective method for CAD detection. Materials and Methods: Of 430 consecutive patients suspected with CAD, 104 performed both MPI (with the method of exercise stress) and ICA (Invasive Coronary Angiography). Luminal stenosis > 70% read by ICA was defined as significant CAD. Considering ICA as the gold standard, we calculated sensitivity, specificity, NPV and PPV for both tests. Besides, the relationship between CAD risk factors and findings of the procedures was also computed, using chi-square and student t-tests. Results: Sensitivity, specificity, PPV and NPV of MPI and exercise test for detection of CAD were: 90.74%, 92%, 92.45%, 90.19%, and 57%, 82%, 77.5%, 63.1%, respectively. A significant relationship between diabetes and hyperlipidemia with abnormal perfusion MPI and positive exercise test was found (P<0.05).Relatively poor agreement was observed between results of MPI and exercise test (kappa statistic = 0.445). Conclusion: Not only dose MPI benefits from higher diagnostic value for diagnosis of CAD, but it also can be used in patient risk stratification and applying more appropriate therapeutic strategies.