Nutrition, metabolism, and the complex pathophysiology of cachexia in chronic heart failure.

Chronic heart failure is a complex catabolic state that carries a devastating prognosis. The transition from stable disease to cardiac cachexia is not well understood. Mechanisms that maintain the wasting process involve neurohormones and pro-inflammatory cytokines, which contribute to an imbalance in anabolic and catabolic pathways. A decrease in food intake alone rarely triggers the development of a wasting process, but dietary deficiencies in micronutrients and macronutrients contribute to the progression of the disease. Malabsorption from the gut as a result of bowel wall edema and decreased bowel perfusion also plays an important role. This article describes the complex interplay of hormonal systems in energy balance in patients with chronic heart failure as well as other factors such as malabsorption and dietary deficiencies that contribute to the wasting process. Finally, therapeutic approaches are discussed. These include dietary advice, ongoing studies, and future possibilities.