[Cachexia and sarcopenia in chronic heart failure : Change in muscle strength and muscle structure].

Alterations to the body composition, i.e. the makeup of skeletal muscle, fat and bone density, are frequent in heart insufficiency. Their prevalence and clinical consequences are often underestimated. Cachexia is recognized as a complex multifactorial syndrome in chronic diseases that leads to weight loss. This point constitutes the essential differential criterion from sarcopenia. Cachexia is defined as a non-edematous weight loss of more than 5% within 12 months or less. Cachexia means weight loss, while sarcopenia means loss of muscle mass without weight loss because the functional muscle can be replaced by adipocytes. Sarcopenia is defined as a skeletal muscle mass index (SMMI) of at least 2 standard deviations below the mean value of a healthy young reference group between 20 and 30 years of the same sex and ethnic background. At the same time the walking speed is reduced to 1 m/s or the distance covered in a 6-min walk is <400m. The determination of loss of muscle mass should be carried out by whole body scanning, ideally with dual-energy x‑ray absorptiometry. A reliable and simple method for measurement of performance capability is the short physical performance battery (SPPB) test. The treatment of sarcopenia and cardiac cachexia in patients with heart insufficiency is still a great challenge. Power and endurance training, nutritional supplementation and drug therapy are possible therapeutic approaches; however, the study situation is unsatisfactory.