Prediction of left main coronary artery stenosis by exercise electrocardiography

The possibilities of predicting left main coronary artery stenosis (LMCAS) by the T wave pattern in exercise ECG were studied in a consecutive series of patients with stable angina pectoris and were compared to the predictive ability of ST criteria. After exclusion of patients with interfering diagnoses and digitalis treatment, 146 patients remained; 16 of them had LMCAS. Appearance or increase of a biphasic or negative T wave in leads V2-6 2 min after exercise detected 63% of the LMCAS, and the predictive value of a positive test was 36%. The sensitivity of the ST criteria was only 38% and the predictive value 26%. The observer concordance was 98% for the T wave and 84% for the ST criteria. These T wave criteria are at least as sensitive and predictive as the ST criteria and easier to apply.