Do discriminant analysis or heart rate-adjusted ST segment amplitude changes improve diagnostic accuracy for coronary artery disease compared to standard exercise scores during bicycle ergometry in men without prior MI?
Discriminant analysis and heart rate-adjusted ST segment amplitude changes provide excellent diagnostic accuracy for coronary artery disease during exercise testing, outperforming standard ST depression area scores.
The diagnostic accuracy of the following methods of analysing exercise tests were evaluated: (a) the cumulative area of ST segment depression during exercise normalised for workload and heart rate (exercise score); (b) discriminant analysis of electrocardiographic exercise variables, workload, and symptoms; and (c) ST segment amplitude changes during exercise adjusted for heart rate. Three hundred and forty five men without a history of myocardial infarction were studied. One hundred and twenty three were apparently healthy. Less than half (170) had coronary artery disease. All had a normal electrocardiogram at rest. A Frank lead electrocardiogram was computer processed during symptom limited bicycle ergometry. The accuracy of the exercise score (a) was low (sensitivity 67%, specificity 90%). Discriminant analysis (b) and ST segment amplitude changes adjusted for heart rate (c) had excellent diagnostic characteristics (sensitivity 80%, specificity 90%), which were little affected by concomitant use of beta blockers. Both methods seem well suited for diagnostic application in clinical practice.
Deckers et al. (1989) studied this question.