Prognosis after myocardial infarction.

There is 10-20 percent mortality in the first two years after hospital discharge from a myocardial infarction. Patient management would be facilitated if one could stratify patients into those who have a low, medium or high risk of death within the first two years following infarction. Towards achieving this end a multicenter study was designed. 866 patients were enrolled over a two-year period from four widely separated geographic centers in the United States. Criteria for enrollment included definite acute myocardial infarction and age less than 70 years. 452 clinical variables were obtained from each patient and entered into a central computer file. Special studies obtained just prior to discharge included a 24-hour computer analyzed Holter recording and a radionuclide ejection fraction. 70 percent of the patients had a low-level predischarge treadmill activity test. Before the study a hypothesis was generated and tested prospectively. This was as follows: there are three clinical risk variables that have independent influence on survival. They are: ejection fraction less than 40 percent, ventricular ectopic depolarization frequency greater than 10 per hour, and the presence of angina pectoris before hospital discharge. The 22-month mortality was 11.6 percent (101 deaths). The variables which had the most significant association with cardiac mortality were those which reflected mechanical cardiac dysfunction either before or during acute hospitalization. The arrhythmia variable (VEDs) were less strongly associated with mortality than the mechanical parameters and the ischemia variable (angina pectoris prior to discharge) did not significantly discriminate between those who survived and died.(ABSTRACT TRUNCATED AT 250 WORDS)