Purpose of review
This article aims to describe molecular pathways involved in the development of muscle wasting and cachexia, diagnostic possibilities, and potential treatments that have seen clinical testing in recent heart failure trials. An understanding of the specific changes that cause an anabolic-catabolic imbalance is an essential first step in the development of pharmaceutical intervention strategies aimed at blocking muscle wasting.
Skeletal muscle mass and muscle strength are the most important determinants of exercise capacity in patients with heart failure. In contrast to cachexia, muscle wasting is not usually associated with weight loss, implying the need for sophisticated assessment methods to correctly diagnose muscle wasting, for example the use of computed tomography, magnetic resonance imaging, or dual energy X-ray absorptiometry. Simpler techniques such as handgrip strength, exercise testing, or even a biomarker may help in determining patients with a high pre-test probability of muscle wasting.
Despite intensive research efforts in the field of muscle wasting during the last couple of decades, no effective treatment of muscle wasting currently exists other than exercise training. This situation remains true even though study of the molecular pathways involved in muscle wasting suggests many therapeutic targets. Easily applicable diagnostic tools may help to identify patients at risk of developing muscle wasting.