Cardiac Cachexia: Pathophysiology and Clinical Implications

Cardiac cachexia (i.e. body wasting) has long been recognised as a serious complication of chronic heart failure (CHF) which affects many body systems and remains an important and increasing public health problem. The occurrence of wasting in CHF has been known for many centuries but little investigated. Independently of functional disease severity, age, and measures of exercise capacity and cardiac function, cardiac cachexia is associated with poor prognosis. Cachectic CHF patients are weaker and fatigue earlier because of a general loss of fat tissue, lean tissue and bone tissue as well as impaired muscle quality. There is a shift of understanding of pathophysiology of cardiac cachexia with increasing evidences that metabolic, neurohormonal and immune abnormalities may play a significant role as well the degree of body wasting is dependent on such changes. It has been shown that cardiac cachexia is linked to raised plasma levels of tumor necrosis factor alpha and other inflammatory cytokines and increased concentration of epinephrine, norepinephrine, and cortisol. Furthermore, they also present high plasma renin activity and increased plasma aldosterone level. Cardiac cachexia may be the result of a multifactorial neuroendocrine and metabolic disorder and of a complex imbalance of different body systems.