Exercise training program in patients with NYHA III class systolic heart failure - Parallel comparison to the effects of resynchronization therapy.

Purpose: The aim of this study was to assess exercise capacity and echocardiographic parameters in patients with heart failure with reduced ejection fraction (HFrEF) in NYHA III functional class, after cardiac resynchronization therapy (CRT) or implantable cardioverter-defibrillator (ICD) implantation followed by 6 months of supervised rehabilitation in ICD patients.

Materials And Methods: The study included patients with HFrEF and impaired left ventricle systolic function (LVEF ≤ 35%), divided into two groups: CRT group - patients after CRT-D implantation > six weeks, and ICD-rehab group - patients after ICD implantation > six weeks, followed by 6 months of supervised aerobic interval training and the conditioning exercises. At baseline and after 6 months in all the patients cardiopulmonary exercise tests (CPX) and standard echocardiographic examinations were performed.

Results: The study included 61 patients (49-77 years) with HFrEF. At baseline, the values of CPX parameters were similar in both groups. After completing training almost all CPX parameters in the ICD-rehab group significantly improved, except for anaerobic threshold (AT). In the CRT group significant improvements were found in 2 parameters: peak oxygen uptake (VO) and exercise tolerance (metabolic equivalents, METs). Significant reductions in left and right ventricle diameters and an increase in LVEF were observed in both groups after 6 months.

Conclusions: Significant improvement in exercise tolerance capacity and increase of LVEF were observed in similar extent both in heart failure patients with CRT and with ICD undergoing the rehabilitation program. Regular, controlled exercise trainings provided additional, safe and easy to conduct therapeutic option for heart failure patients with no indications for CRT.