Patients with heart failure are limited in their exercise capacity due to skeletal muscle alteration and an impairment of peripheral perfusion. Regular physical exercise training has been shown to partially correct these peripheral maladaptations in patients with stable heart failure, which was associated with an improvement in exercise capacity. However, it is unknown so far, whether regular physical activity also exerts beneficial effects in patients with severe chronic heart failure.

Aim of the trial is therefore to assess the effects of aerobic exercise training on exercise capacity, muscle maladaptations and peripheral perfusion in patients with severe chronic heart failure according to NYHA class III b.

A total of 36 patients with severe chronic heart failure are prospectively randomized to either 3 months of aerobic ergometer training or a sedentary control group.

Before and after the intervention period maximal exercise capacity is assessed by ergospirometry, endothelial function is determined by high-resolution A-mode ultrasound, and muscle mass is determined by CT. Skeletal muscle biopsies are obtained at begin and after 3 months and are analyzed for markers of muscle catabolism/anabolism.

Inclusion Criteria:

• chronic heart failure (NYHA class III b)
• peak oxygen uptake <20 mL/min/kg body weight
• left ventricular ejection fraction <25 %
• left ventricular end-diastolic diameter >60 mm

Exclusion Criteria:

• exercise-induced myocardial ischemia
• cardiac decompensation within the last 8 weeks
• ventricular arrhythmias (>Lown 4b) in patients not protected by an ICD
• insulin-dependent diabetes mellitus
• uncontrolled arterial hypertension
• orthopedic conditions excluding training participation
• body mass index >30 kg/m2