Changes in exercise capacity and modifiable risk factors after a comprehensive cardiac rehabilitation in patients with and without left ventricular systolic dysfunction

Background: Although the positive effects of cardiac rehabilitation (CR) for patients with heart failure have been known, only a small proportion of such patients have been referred for comprehensive CR. The aim of this study is to compare the extent to which a CR program improved the exercise capacity and modifiable risk factors of patients with and without impaired systolic function. Methods: This study was an observational study undertaken in Imam Ali Hospital in Kermanshah (2001-2006), the only referral center for CR in the west of Iran. 502 patients, who completed CR program, were included in this study. They were divided into two groups: impaired systolic function with  ejection fractions (EF) <50% (n=185) and normal systolic function (EF≥50%, n=317). Results: Both groups were comparable in terms of all baseline characteristics such as BMI, hypertension, smoking and diabetes. There were significant improvements in  exercise capacity, BMI, waist circumference, total cholesterol, LDL, triglyceride, systolic and diastolic blood pressure and depression score in both groups after CR (P<0.001). However, the effect of CR on HDL did not reach a statistical significant level in either group. In addition further analyses showed that there was no statistically significant differences between patients with severe impaired systolic function (EF<35%) and normal EF, however changes in lipid profiles were not stastically  significant.  Conclusion: This study confirmed that the effects of CR on improvement of exercise capacity and risk profiles are almost equal in patients with and without systolic dysfunction.