Evaluation of pretest and exercise test scores to assess all-cause mortality in unselected patients presenting for exercise testing with symptoms of suspected coronary artery disease

OBJECTIVES: To determine how well recently developed multivariables scores assess for all-cause mortality in patients with suspected coronary disease presenting for exercise electrocardiography (ExECG). BACKGROUND: Recently revised American College of Cardiology/American Heart Association guidelines for ExECG have suggested that ExECG scores be used to assist in management decisions in patients with suspected coronary artery disease. Recently developed scores accurately stratify patients according to angiographic disease severity. METHODS: To determine how well these scores assess for all-cause mortality, we utilized 4,640 patients without known coronary disease who underwent ExECG to evaluate symptoms of suspected coronary disease between 1995 and 2001. Previously validated pretest and exercise test scores as well as the Duke treadmill score were applied to each patient. All-cause mortality was our end point. RESULTS: Overall mortality was 3.0% with 2.8 +/- 1.6 years of follow-up. All three scores stratified patients into low-, intermediate-, and high-risk groups (p < 0.00001). No differences were seen when patients were evaluated as subgroups according to gender, diabetes, beta-blockers, or inpatient status. Low-risk patients defined by the Duke treadmill score had consistently higher mortality and absolute number of deaths compared with low-risk patients using other scores. In addition, the Duke treadmill score had less incremental stratifying value than the new exercise score. CONCLUSIONS: Simple pretest and exercise scores risk-stratified patients with suspected coronary disease in accordance with published guidelines and better than the Duke treadmill score. These results extend to diabetics, inpatients, women, and patients on beta-blockers.