Prognostic value of a treadmill exercise score in outpatients with suspected coronary artery disease.

Journal Article (Clinical Trial;Journal Article)

BACKGROUND: The treadmill exercise test identifies patients with different degrees of risk of death from cardiovascular events. We devised a prognostic score, based on the results of treadmill exercise testing, that accurately predicts outcome among inpatients referred for cardiac catheterization. This study was designed to determine whether this score could also accurately predict prognosis in unselected outpatients. METHODS: We prospectively studied 613 consecutive outpatients with suspected coronary disease who were referred for exercise testing between 1983 and 1985. Follow-up was 98 percent complete at four years. The treadmill score was calculated as follows: duration of exercise in minutes--(5 x the maximal ST-segment deviation during or after exercise, in millimeters)--(4 x the treadmill angina index). The numerical treadmill angina index was 0 for no angina, 1 for nonlimiting angina, and 2 for exercise-limiting angina. Treadmill scores ranged from -25 (indicating the highest risk) to +15 (indicating the lowest risk). RESULTS: Predicted outcomes for the outpatients, based on their treadmill scores, agreed closely with the observed outcomes. The score accurately separated patients who subsequently died from those who lived for four years (area under the receiver-operating-characteristic curve = 0.849). The treadmill score was a better discriminator than the clinical data and was even more useful for outpatients than it had been for inpatients. Approximately two thirds of the outpatients had treadmill scores indicating low risk (greater than or equal to +5), reflecting longer exercise times and little or no ST-segment deviation, and their four-year survival rate was 99 percent (average annual mortality rate, 0.25 percent). Four percent of the outpatients had scores indicating high risk (less than -10), reflecting shorter exercise times and more severe ST-segment deviation; their four-year survival rate was 79 percent (average annual mortality rate, 5 percent). CONCLUSIONS: The treadmill score is a useful and valid tool that can help clinicians determine prognosis and decide whether to refer outpatients with suspected coronary disease for cardiac catheterization. In this study, it was a better predictor of outcome than the clinical assessment.

Full Text

Duke Authors

Cited Authors

  • Mark, DB; Shaw, L; Harrell, FE; Hlatky, MA; Lee, KL; Bengtson, JR; McCants, CB; Califf, RM; Pryor, DB

Published Date

  • September 19, 1991

Published In

Volume / Issue

  • 325 / 12

Start / End Page

  • 849 - 853

PubMed ID

  • 1875969

International Standard Serial Number (ISSN)

  • 0028-4793

Digital Object Identifier (DOI)

  • 10.1056/NEJM199109193251204


  • eng

Conference Location

  • United States