The authors investigated the levels of plasma renin activity and aldosterone in patients with a fresh myocardial infarction during the first 24 hours of hospitalization. The values of plasma renin activity and aldosterone were correlated with values of the control group. At the time of admission to the clinic both hormones were significantly elevated, as compared with the control group, in plasma renin activity p less than 0.001 and in aldosterone p less than 0.01. During the subsequent time intervals, i.e. after 3, 6 and 24 hours, the values of plasma renin activity did not change substantially, while the aldosterone values declined during the 6th and 24th hour (significance p less than 0.05). No significant relationship was found between plasma renin activity an aldosterone. With regard to persisting elevated values of plasma renin activity the authors discuss the possible use of blockers of the angiotensin converting enzyme in order to inhibit in the initial stage of a new infarction the formation of endogenous pressor substances.

Keywords: Aldosterone /blood/; Female; Humans; Male; Middle Aged; Myocardial Infarction /blood/; Renin /blood/; Time Factors