Effects of a cardiac rehabilitation program on systolic function and left ventricular mass in patients after myocardial infarction and revascularization

Supervised exercise-based cardiac rehabilitation programs (CRP) have been suggested to all patients, especially after myocardial infarction. However, the effects of cardiac rehabilitation on systolic function are controversial. The aim of this study was to examine the effects of an 8-week cardiac rehabilitation on left ventricular systolic function and left ventricular mass in patients with myocardial infarction (MI) and revascularization. METHODS: This study included 29 men with MI after reperfusion therapy, i.e. coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI). The patients were randomized into a training group (n = 15, mean age: 54.2 ± 9.04 years) and a control group (n = 14, mean age: 51.71 ± 6.98 years). The training group performed 8 weeks of CRP with an intensity of 60-85% of maximum heart rate, 3 times a week. Each session lasted for 60 minutes. Before and at the end of the study, all patients underwent 2-dimentional echocardiography for left ventricular systolic function and left ventricular mass to be assessed. RESULTS: After 8 weeks of CRP, left ventricular ejection fraction (LVEF) increased significantly in the training group (48.53 ± 10.41 vs. 59.13 ± 5.90; p < 0.001). Moreover, the difference in LVEF between the training and control groups were significant after the course (59.13 ± 5.90 vs. 55.90 ± 9.60; p < 0.001). In addition, stroke volume increased significantly (57.22 ± 7.84 ml vs. 64.03 ± 12.80 ml; p < 0.001) while left ventricular systolic volume decreased significantly (42.89 ± 17.32 ml vs. 31.00 ± 8.34 ml; p < 0.001) in the training group. CRP was decreased left ventricular mass in the training group (229 ± 42 vs. 196 ± 34; p < 0.05). CONCLUSIONS: A 2-month CRP in post-MI patients led to improvements in systolic function and reductions in left ventricular mass and thus cardiomegaly.