Raoul Malmcrona

Hemodynamic effects of metaraminol

Abstract Ten middle-aged subjects without cardiovascular disease were given metaraminol at two infusion rates. Electrocardiograms, intravascular pressures and indicator-dilution curves were recorded. Heart rate fell and arterial pressures and stroke volume rose in most subjects. Small increases in brachial arterial pressures were due to small increases in peripheral resistance and cardiac output. Greater increases in pressure essentially depended on further increase in peripheral resistance. In 5 of the 10 subjects arrhythmias were seen.

Hemodynamic effects of metaraminol: II. Patients with acute myocardial infarction☆

Abstract Eleven patients with acute myocardial infarction have been studied by recordings of intraarterial pressure and determinations of cardiac output before, during and, in 7 cases, also after cessation of metaraminol infusion. The heart rate was lower and the stroke volume higher in the patients during infusion. The arterial pressure rose in all patients. In some the rise depended on a rise in cardiac output, in some on a rise in resistance, but in most patients on small rises in both output and resistance. The type of reaction was not directly correlated to the factor apparently responsible for a low blood pressure. Metaraminol seems thus a useful drug when the blood pressure decreases after myocardial infarction and may also be of value in the treatment of cardiogenic shock.

Heart rhythm in patients with neurofibromatosis type 1.

Neurofibromatosis type 1 (NF1) is a common inherited disorder. Neurofibromas may be situated almost anywhere in the body, including mediastinum, myocardium and autonomic nervous system. We, therefore, tested our hypothesis that arrhythmias would be more common during a 24-hour period in patients with NF1 than in control subjects. In a follow-up study of NF1 patients in Gothenburg, 38 out of 47 NF1 patients entered a study for comparison with 41 controls. We did not find any excess of arrhythmias. There were, however, fewer cases with episodes of bradycardia among the NF1 patients (p < 0.01) than among the controls. This might be explained by vagus nerve involvement.