Disability in COPD and Chronic Heart Failure Is the Skeletal Muscle the Final Common Pathway?

Chronic Obstructive Pulmonary Disease (COPD) and Chronic Heart Failure (CHF), two major causes of worldwide morbidity and mortality have important systemic components, affecting additional tissues, other than the lung or the heart, such as the skeletal muscle. Muscle function (or dysfunction) may not only influence the symptoms that limit exercise, but may contribute directly to the poor exercise performance, health status and increased healthcare utilization.The present review tries to summarize the muscular abnormalities in COPD and CHF and the mechanisms underlying these alterations, which are strikingly similar, despite the obvious differences concerning the primary impairment in these two chronic diseases.The muscles therefore represent a potential site to improve patients' functioning level and quality of life of COPD and CHF. Only one practical therapeutic intervention currently exists that can reverse some of the muscle abnormalities observed in COPD and CHF, namely exercise training, which becomes nowadays the "cornerstone" of the whole rehabilitation.