On the clinical value of conventional and new exercise electrocardiographic criteria: a comparative study.

We have evaluated the clinical value of new electrocardiographic criteria in exercise testing. In this study, we compared both ST-segment and R-wave amplitude criteria, separately and in combination with the findings from coronary arteriography in 122 patients. In these selected patients application of conventional ST-segment criteria gave a sensitivity of 31% and a specificity of 100%; with application of the slow upsloping ST-segment criteria the sensitivity was 51% and the specificity 82%. Analysis of R-wave amplitude changes alone led to a sensitivity of 50% and a specificity of 61%. In combined interpretation of ST-segment and R-wave amplitude changes the sensitivity was 51% and the specificity 93%. We conclude that slow upsloping ST-segment criteria constitute the most important recent improvement in interpreting exercise test results and that the value of R-wave amplitude changes during exercise in diagnosing significant coronary artery disease is rather low in the individual patient. R-wave amplitude changes, however, may have value in patients with a previous myocardial infarction and in reducing false-negative and false-positive responses according to ST-segment criteria. Combined interpretation of ST-segment and R-wave amplitude criteria is useful but not very efficient.