Comparison of Computerized and Standard Visual Criteria of Exercise ECG for Diagnosis of Coronary Artery Disease

Objective: To review past and current studies of computerized exercise ECG criteria in order to establish which, if any, are superior to standard visual analysis for the diagnosis of coronary artery disease (CAD). Methods: Prior studies that compared multiple computerized ECG criteria were reviewed. In addition, we investigated two sets of patients that had both exercise testing and coronary arteriography at two university‐affiliated Veteran's Affairs Medical Centers. Patients with previous myocardial infarction or coronary artery bypass surgery, valvular heart disease, left bundle branch block, or any diagnostic Q waves present on their resting ECGs were excluded from analysis. Sensitivity and specificity values were compiled for standard visual analysis and for the following computerized ECG criteria: ST0; ST60; ST slope; ST integral; ST index; R wave adjusted ST; ST/heart rate (HR) index; Hollenberg's Treadmill exercise score; and discriminant function analysis (DFA). Results: Despite the effects of limited challenge and work‐up bias, the compiled results indicate that ST measurements recorded during the time of recovery from exercise are substantially more diagnostic than those recorded at maximal exercise. ST integral, ST60, and R wave adjusted ST60 during recovery are especially discriminating of CAD, while Hollenberg's treadmill exercise score is not. There were inconclusive results for HR adjustments to ST depression and ST index. DFA including visual analysis of the ECG consistently exhibited the greatest discriminating power of all computerized results. Conclusion: Although DFA, ST integral during recovery, or ST60 during recovery exhibited improved predictive value, further research is necessary before we can clearly offer a superior alternative to standard visual analysis.