Haemodynamic dose-response effects of i.v. metoprolol in coronary heart disease

The haemodynamic effects of intravenous metoprolol, over the dose-range 2.5--20 mg, were studied in 12 patients with coronary heart disease. The pharmacodynamic activity of the drug was confirmed by the suppression of exercise systolic pressure and tachycardia. There were statistically significant dose-response reductions in systolic and diastolic pressures, heart rate and cardiac output together with a dose-related increase in pulmonary wedge pressure. In patients with coronary heart disease intravenous metoprolol should probably not exceed the doses used in this study and should be administered with caution in patients with impairment of pumping function.