[Effects of Astragalus membranaceus on left ventricular function and oxygen free radical in acute myocardial infarction patients and mechanism of its cardiotonic action].

Dynamic observations for 4 weeks were made on left ventricular function and oxygen free radical (OFR) in 43 patients first suffering from acute myocardial infarction and hospitalized in Coronary Care Unit with an attack less than 36 hours. The results showed that the Astragalus membranaceus (AM) could strengthen the left ventricular function and had an effect of anti-OFR. After administration of AM, the ratio of pre-ejection period/left ventricular ejection time (PEP/LVET) was decreased, the superoxide dismutase (SOD) activity of red blood cell was increased, and the lipid peroxidation (LPO) content of plasma was reduced. There was a significant difference between the AM group and the control group in the parameters above-mentioned. The study demonstrated that the PEP/LVET ratio was closely correlated with the SOD and LPO. It suggested that the anti-OFR effect of AM was one of the mechanisms of its cardiotonic action.