Conclusions Exercise-based cardiac rehabilitation is effective at reducing important clinical outcomes in patients with coronary heart disease .
While our analysis was constrained by the quality of included trials and missing information about intervention components , there appears to be little differential effect of variations in exercise intervention , particularly on mortality outcomes .
Background While the clinical benefits of exercise-based cardiac rehabilitation are well established , there is extensive variation in the interventions used within these trials .
It is unknown whether variations in individual components of these exercise interventions provide different relative contributions to overall clinical outcomes .
This study aims to systematic ally examine the relationship between individual components of the exercise intervention in cardiac rehabilitation ( such as intensity and frequency ) and clinical outcomes for people with coronary heart disease .
Interaction between exercise training and ejection fraction in predicting prognosis after a first myocardial infarction.
BACKGROUND Although recent meta- analysis trials have shown that exercise training may improve survival after myocardial infa rct ion , the mechanism of this beneficial effect is still unknown . The purpose of this study was to detect possible interactions between exercise training and predictors of prognosis after a first myocardial infa rct ion . METHODS AND RESULTS Patients with uneventful clinical courses after a first myocardial infa rct ion were r and omly assigned to a  4-week training period ( 125 patients , group 1 ) or to a  control group ( 131 patients , group 2 ) . Before r and omization , all patients underwent a symptom-limited exercise test ( 28 + /- 2 days after myocardial infa rct ion ) , 24-hour Holter monitoring , and coronary arteriography ( 31 + /- 3 days after the acute episode ) . After a mean follow-up period of 34.5 months , 18 patients had cardiac deaths ( 5 in group 1 and 13 in group 2 ) . Multivariate analysis by Cox regression model showed that ejection fraction was the only independent prognostic indicator ( P = .03 ) . Evidence existed of an interaction between ejection fraction and exercise training , showing an effect of physical training on survival that depended on the patient 's ejection fraction . Among patients with ejection fractions < 41 % , the relative risk for an untrained patient was 8.63 times higher than for a trained patient ( P = .04 ) , whereas for ejection fractions > 40 % , the estimated risks for trained and untrained patients were similar . CONCLUSIONS These data show that exercise training may prolong survival in post-myocardial infa rct ion patients with depressed left ventricular function . A r and omized trial in such patients seems warranted
Conclusions Exercise-based cardiac rehabilitation is effective at reducing important clinical outcomes in patients with coronary heart disease .
While our analysis was constrained by the quality of included trials and missing information about intervention components , there appears to be little differential effect of variations in exercise intervention , particularly on mortality outcomes .
Background While the clinical benefits of exercise-based cardiac rehabilitation are well established , there is extensive variation in the interventions used within these trials .
It is unknown whether variations in individual components of these exercise interventions provide different relative contributions to overall clinical outcomes .
This study aims to systematic ally examine the relationship between individual components of the exercise intervention in cardiac rehabilitation ( such as intensity and frequency ) and clinical outcomes for people with coronary heart disease .