Effects of aerobic physical rehabilitation on muscle fiber metabolism in patients with severe heart failure

Abstract

Abstract Purpose To evaluate changes of functional state and metabolism of skeletal muscle fiber (MF) after aerobic physical rehabilitation (PR), based on original method; to study relationship between clinical data dynamics and indicators of skeletal muscle metabolism after PR. Methods 100 patients; heart failure (HF) with reduced ejection fraction (HFrEF), NYHA III, mean age 52±5,2 years, ejection fraction (EF) 27,3±4,2%, BMI 23,5±2,8 kg/m2. Before inclusion in PR program cardiopulmonary exercising test (CPET), echocardiography (EchoCG), quality of life (QOL), exercise tolerance (ET) were estimated. Physical training intensity was based on lactate threshold achievement during CPET. PR efficiency was estimated on the basis of peak oxygen uptake (VO2peak), EF, QOL and ET dynamics after 6 months PR. Shin muscle biopsy was performed at baseline and after 3–6 months PR. In muscle samples activity of alkaline phosphatase (AP), lactate dehydrogenase (LDH) and succinate dehydrogenase (SDG) was evaluated with plag-method. Data were statistically processed using software package “Statistika, 9.0”. Results After 6 months of training EF increased by 10,5±2,3%, ET increased by 9,7±0,5 points (p1,2 <0,05), QOL changed by 24,8±3,5 points (significant regression of symptoms), VO2peak increased by 5,2±0,5 ml/min/kg (p3,4 <0,05). MF diameter (dMF) after PR slightly decreased in 6 patients, in 2 patients it did not change. After 3–6 months of training AP activity increased by 24,2% (p<0,05); LDH activity in glycolytic MF decreased by 24,4%, in oxidative MF it decreased by 6,0% only (p1 <0,05, p2>0,05). SDG activity in glycolytic MF increased by 20%, in oxidative MF it increased by 30% (p1 <0,05, p2<0,05). There was a positive relationship between heart failure functional class dynamics and dMF (r=0,4, p=0,05), increase in CPET parameters was associated with AP activity (r=0,5, p=0,05). Conclusion Aerobic physical rehabilitation in stable HF pts, selected on the basis of LT achievement, was effective in improving values of EF, QOL, VO2peak and ET. After 3–6 months PR dMF slightly decreased; Participating in the PR program decreased LDH activity in both oxidative and glycolytic muscle fibers; it also increased AP and SDG activity significantly. This may indicate an increase in oxidative metabolism activity and decrease in MF edema, improvement in skeletal muscles microcirculation. Funding Acknowledgement Type of funding sources: None.