RESUMO
The effect of metoprolol in ECG experiments induced by a treadmill exercise test, was studied in 30 patients with stable angina pectoris. The study was a simple blind cross-over between metoprolol (150 mg/die) and placebo. The evaluation of ECG recordings (V5 lead) was carried out by a computer program. In order to assess the ST-segment depression, the ST 0.8 (Depression at 80 msec after R-peak) and AST (ST area) values were used. We observed an increased exercise tolerance after administration of metoprolol (P less than 0.001) and a significant reduction of ST segment depression for ST 0.8 (P less than 0.01) and AST (P less than 0.005) at the maximal commun work load attained by every patient in the metoprolol and placebo tests. When the evaluation of ECG measurements were performed at the maximal commun double product no significant modifications were observed.