Background — The appropriate management of patients with an intermediate Duke treadmill score (DTS) is not well established. The aim of this study is to compare several treadmill indexes (American College of Cardiology/American Heart Association (ACC/AHA) High-Risk Criteria for exercise testing, Veterans Affairs and West Virginia Prognostic Score, ST/Heart Rate Index, Failure to attain 85% of age-predicted maximum Heart Rate) with ST-segment depression in detecting significant or severe coronary artery disease as determined by coronary angiography in patients with an intermediate DTS.Methods — 144 consecutive patients admitted to the hospital for unstable angina were studied.Results — The sensitivities of the ACC/AHA High-Risk Criteria and West Virginia Prognostic Score were greater than 95% for the detection of significant coronary artery disease and 96.67% for the detection of severe coronary artery disease. The sensitivity of 1 mm ST depression for the detection of significant and severe coronary disease was 74.74% and 86.67%, respectively.The combined evaluation of ST-segment depression ≥ 1 mm and exercise-induced angina could efficiently identify a population with a high prevalence of significant coronary artery disease (specificity of 95.92%, positive predictive value of 94.29%).Conclusions — The ACC/AHA High-Risk Criteria and West Virginia Prognostic Score provided relevant diagnostic information in patients with an intermediate DTS.A coronary angiography is to be recommended in patients with an intermediate DTS who also present ST-segment depression ≥ 1 mm and exercise-induced angina.