Optimal Initial Diagnostic Strategies for the Evaluation of Stable Angina Patients - A Multicenter, Prospective Study on Myocardial Perfusion Imaging, Computed Tomographic Angiography, and Coronary Angiography

Background: For stable patients suspected of having coronary artery disease (CAD), myocardial perfusion imaging (MPI) or computed tomographic angiography (CT) is used for initial evaluation, while coronary angiography (CAG) is used for confirming the diagnosis. The choice of the initial diagnostic test might influence the treatment strategy. Methods and Results: Patients scheduled for MPI, CT, or CAG as the initial diagnostic test were enrolled. The primary and secondary end-points were a major adverse cardiac event (MACE) and revascularization, respectively. Of the 2,878 patients enrolled, 2,825 underwent initial diagnostic tests, and 2,780 were followed up for 1.42 +/- 0.49 years. After adjustment for CAD severity, Cox proportional hazard regression analysis showed that the risk of MACE in the MPI and CT groups were similar and significantly less than that in the CAG group (hazard ratio, 0.82 vs. 2.19; 95% confidence interval [CI], 0.43-1.58 vs. 1.40-3.44). Furthermore, the rate of revascularization in the MPI group was less than that of the CT (odds ratio, 1.62; 95% CI, 1.20-2.18) and CAG (odds ratio, 5.36; 95% CI, 4.07-7.05) groups. Conclusions: These data indicate that for stable patients with suspected CAD, the use of MPI or CT as the initial diagnostic test was associated with better prognosis than the use of CAG, and that initial evaluation with MPI was associated with a lower requirement of coronary intervention. (Circ J 2012; 76: 2832-2839)