Objective: The autonomic dysfunction is known to adversely affect clinical outcome in patients with cardiovascular disease, and exercise training has been shown to modify the sympathovagal control of heart rate. The purposes of this study were to investigate the effect of cardiac rehabilitation on heart rate recovery in patients who received coronary artery bypass grafting (CABG) and compare the effect with that of a home-based exercise program.
Design: Fifty-four male patients having undergone CABG were randomly assigned to a cardiac rehabilitation exercise program (n = 18), a home-based exercise program (n = 18), and a control group (n = 18) for 12 wks to evaluate the differences in heart rate recovery among groups.
Results: Patients in the cardiac rehabilitation group had significant increases in heart rate recovery (19.1 +/- 6.2 vs. 14.0 +/- 5.4 beats/min, P = 0.022) compared with those in the control group. There were no significant differences in heart rate recovery between cardiac rehabilitation and home-based exercise groups (16.2 +/- 4.8 beats/min) or between home-based exercise and control groups. All three groups had significantly improved heart rate recovery compared with their baseline data (P < 0.001, < 0.001, and 0.007).
Conclusion: Our results point out that a cardiac rehabilitation exercise program has a positive effect on heart rate recovery in patients having undergone CABG and is consistent with the autonomic improvement. Although the home-based exercise group did not reveal statistical significances over those in the control group, it had comparable efficacy to that demonstrated in the cardiac rehabilitation group.