Simple clinical data are useful in predicting effect of exercise training after myocardial infarction

Abstract

Objectives. The aim of the present study was to determine whether simple clinical variables can predict the effect of intensive exercise training in an unselected population early after myocardial infarction. Methods. Starting 5 weeks after the qualifying myocardial infarction, 105 patients, 68 years old or younger, completed a 4 week period of intensive exercise training. The training effect was defined as an absolute increase in cumulative work at bicycle ergometry. Using univariate and multivariate analysis, 28 variables were tested against the training effect. Results. The mean exercise capacity increased from 46.7 ± 22.7 kJ to 69.5 ± 31.1 kJ (P = 0.0001). Multivariate analysis identified five independent predictors of the training effect. Myocardial infarct size was associated with a better training effect (P = 0.0018), as was male gender (P = 0.0042) and ability to exercise to exhaustion at the baseline exercise test (P = 0.0124). Older age (P = 0.0017) and treatment with beta-adrenergic blocking agents (P = 0.0241) were associated with a lower effect from training. These five variables explained 33% of the variations in effect from training. Patients suffering in-hospital cardiac complications or congestive heart failure achieved a training effect at least as great as patients without cardiac complications. Conclusions. Five simple clinical variables, including infarct size, can assist in the selection of patients for exercise training after myocardial infarction.