Controversies and Conundrums in Cardiac Cachexia: Key Questions About Wasting in Patients With HFrEF.

Cardiac cachexia is characterized by unintentional catabolic weight loss, decreased appetite, and inflammation and is common in patients with stage D (advanced) heart failure with reduced ejection fraction (HFrEF). Cardiac cachexia and related muscle-wasting syndromes are markers of, and a consequence of, the heart failure (HF) syndrome. Although many potential modalities for identifying cardiac cachexia exist, the optimal definition, diagnostic tools, and treatment options for cardiac cachexia remain unclear. Furthermore, it remains unclear whether attempts to reverse muscle wasting prior to advanced HF surgeries, such as left ventricular assist devices and heart transplantation, can improve outcomes. It is important that HF clinicians and dietitians are aware of the pathophysiology and mechanisms of muscle-wasting syndromes in patients with HF, to aid in the recognition and risk stratification of advanced HFrEF. Although the opportunities and rationale for attempting to address cardiac cachexia prior to advanced HF surgeries are uncertain, recent publications suggest that control of the neurohumoral syndrome of advanced HF may be important to permit the recovery of skeletal muscle mass.