Right Ventricular Function and Beneficial Effects of Cardiac Rehabilitation in Patients With Systolic Chronic Heart Failure.

Background: It has been recognized that a comprehensive cardiac rehabilitation (CR) program improves mortality in patients with chronic heart failure. On the other hand, the magnitude of the improvement in exercise capacity after CR differs among individuals. The aim of this study was to assess the echocardiographic determinants of responders to CR using preload stress echocardiography.

Methods: We prospectively enrolled 58 chronic heart failure patients with reduced left ventricular ejection fraction (aged 62 ± 11 years; 69% male; left ventricular ejection fraction 43% ± 7%) who had received optimized medical treatment in a CR program for 5 months. We performed preload echocardiographic studies using leg positive pressure (LPP) to assess the echocardiographic parameters during preload augmentation. We defined 41 patients as a development cohort to assess the predictive value of echocardiographic variables. Next, we validated results in the remaining 17 patients as a validation cohort.

Results: In the development cohort, significant improvement in peak oxygen uptake (VO) (>10%) after CR was observed in 58% patients. In a multivariable logistic regression model, the significant predictor of improvement in exercise capacity was right ventricular (RV) strain during LPP (odds ratio: 3.96 per 1 standard deviation; P = 0.01). An RV strain value of -16% during LPP had a good sensitivity of 0.79 and a specificity of 0.71 to identify patients with improvement in peak VO. In the validation cohort, an optimal cutoff value of RV strain value was the same (area under the curve: 0.77, sensitivity: 0.78, specificity: 0.65).

Conclusions: RV strain during LPP may be an echocardiographic parameter for assessing beneficial effects of CR.