Comparison of Usefulness of Exercise Testing Versus Coronary Computed Tomographic Angiography for Evaluation of Patients Suspected of Having Coronary Artery Disease

In patients suspected of having coronary artery disease (CAD), we compared the diagnostic sensitivity and specificity of exercise testing using ST-segment changes alone and ST-segment changes, angina pectoris, and hemodynamic variables compared to coronary computed tomographic angiography (CTA). Quantitative invasive coronary angiography was the reference method (>50% coronary lumen reduction). A positive exercise test was defined as the development of significant ST-segment changes (≥1 mV measured 80 ms from the J-point), and the occurrence of one or more of the following criteria: ST-segment changes ≥1 mV measured 80 ms from the J-point, angina pectoris, ventricular arrhythmia (the occurrence of ≥3 premature ventricular beats), and ≥20 mm Hg decrease in systolic blood pressure during the test. Positive results on CTA were defined as a coronary lumen reduction of ≥50%. In 100 patients (61 ± 9 years old, 50% men, and 29% prevalence of significant CAD), the diagnostic sensitivity and specificity of exercise testing using ST-segment changes was 45% (95% confidence interval 53% to 87%) and 63% (95% confidence interval 61% to 84%), respectively. However, the inclusion of all test variables yielded a sensitivity of 72% (95% confidence interval 53% to 87%) and a specificity of 37% (95% confidence interval 26% to 49%). The diagnostic sensitivity of 97% (95% confidence interval 82% to 100%) and specificity of 80% (95% confidence interval 69% to 89%) for CTA, however, were superior to any of the exercise test analysis strategies. In conclusion, in patients suspected of having CAD, the diagnostic sensitivity of exercise testing significantly improves if all test variables are included compared to using ST-segment changes exclusively. Furthermore, the superior diagnostic performance of CTA for the detection and exclusion of significant CAD might favor CTA as the first-line diagnostic test in patients suspected of having CAD.