Immediate prognosis in acute myocardial infarction Serial changes in immediate mortality rate and cause of death.

In order to evaluate the effect of coronary care on the immediate mortality rate of acute myocardial infarction and to clarify the problems in coronary care, we attempted to investigate the immediate mortality rate and causes of deaths in 492 patients with acute myocardial infarction who had admitted to the hospital within 24 hours after the onset of infarct from January, 1972 to December, 1981. Three hundred and seventy-nine were men and 113 were women, and their mean age was 61.8 years ranging from 28 to 91 years. One hundred and twenty-seven patients had a previous history of myocardial infarction and 365 patients had none. One hundred and ninety patients of these 365 patients without a previous infarction had anterior infarction, 152 patients inferior infarction and 23 patients subendocardial infarction. All patients were subdivided into four stages according to the time of the onset of infarct: Stage 1 (29 patients); 1972-1975, Stage 2 (101 patients); 1976-1977, Stage 3 (148 patients); 1978-1979 and Stage 4 (214 patients); 1980-1981. No significant differences in age, sex and infarct site among the four periods were found. Time interval between the onset of infarct and admission shortened serially and the ratio of reinfarction to initial infarction increased. Immediate mortality rate (within four weeks after the onset of infarct) was 20.5% in all patients. Immediate mortality rate in Stage 1 was 24.1%, 26.7% in Stage 2, 23.0% in Stage 3 and 15.4% in Stage 4, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)