Effects of Cardiac Rehabilitation Program on Right Ventricular Function after Coronary Artery Bypass Graft Surgery

BACKGROUND Cardiac rehabilitation has been recognized as one of the most effective strategies for managing cardiovascular indices as well as controlling the cardiovascular risk profile, in particular after coronary artery bypass graft surgery (CABG). However, the effect of this program on right ventricular function following CABG is unclear. The aim of this study was to evaluate the impact of cardiac rehabilitation on the right ventricular (RV) function in a cohort of patients who underwent CABG. METHODS A total of 28 patients who underwent CABG and participated consecutively in an 8-week cardiac rehabilitation program at Tehran Heart Center were studied. The control group consisted of 39 patients who refused to attend cardiac rehabilitation and only received postoperative medical treatment after registration in the Cardiac Rehabilitation Clinic. Two-dimensional and Doppler echocardiography was performed to assess the RV function in both groups at the three time points of before surgery, at the end of surgery, and at the end of the rehabilitation program. RESULTS Significant increase of RV function parameters were observed in both rehabilitation group (RG) and control group (CG) at the end of the rehabilitation program compared with post-CABG evaluation in terms of tricuspid annular plane systolic execution (RG: 12.50 mm to 14.18 mm; CG: 13.41 mm to 14.56 mm), tricuspid annular peak systolic velocity (RG: 8.55 cm/s to 9.14 cm/s; CG: 9.03 cm/s to 9.26 cm/s), and tricuspid annular late diastolic velocity (RG: 8.93 cm/s to 9.39 cm/s; CG: 9.26 cm/s to 9.60 cm/s).The parameters of the RV function did improve in both groups, but this improvement was not associated with participation in the complete cardiac rehabilitation program. CONCLUSION The RV function parameters gradually improved after CABG; this progress, however, was independent of the exercise-based cardiac rehabilitation program.