Muscle Wasting and Sarcopenia in Heart Failure—The Current State of Science

Alessia Lena,Markus S Anker,Jochen Springer

doi:10.3390/ijms21186549

Abstract

Sarcopenia is primarily characterized by skeletal muscle disturbances such as loss of muscle mass, quality, strength, and physical performance. It is commonly seen in elderly patients with chronic diseases. The prevalence of sarcopenia in chronic heart failure (HF) patients amounts to up to 20% and may progress into cardiac cachexia. Muscle wasting is a strong predictor of frailty and reduced survival in HF patients. Despite many different techniques and clinical tests, there is still no broadly available gold standard for the diagnosis of sarcopenia. Resistance exercise and nutritional supplementation represent the currently most used strategies against wasting disorders. Ongoing research is investigating skeletal muscle mitochondrial dysfunction as a new possible target for pharmacological compounds. Novel agents such as synthetic ghrelin and selective androgen receptor modulators (SARMs) seem promising in counteracting muscle abnormalities but their effectiveness in HF patients has not been assessed yet. In the last decades, many advances have been accomplished but sarcopenia remains an underdiagnosed pathology and more efforts are needed to find an efficacious therapeutic plan. The purpose of this review is to illustrate the current knowledge in terms of pathogenesis, diagnosis, and treatment of sarcopenia in order to provide a better understanding of wasting disorders occurring in chronic heart failure.

Highlights

Sarcopenia is defined as a diminished muscle strength, rooted in a reduction of muscle quantity and quality, often associated with reduced physical performance, according to the new definition of the European Working Group on Sarcopenia in Older People [1]
Sarcopenia is commonly observed in older patients, with a prevalence between 10 and 40%, depending on the definition used and the age range used in the studies [4]
These changes result in fewer mitochondria, reduction of respiratory complex expression and activity, as well as low nicotinamide adenine dinucleotide (NAD+) levels due to its disturbed biosynthesis [41]

Summary

Introduction

Sarcopenia is defined as a diminished muscle strength, rooted in a reduction of muscle quantity and quality, often associated with reduced physical performance, according to the new definition of the European Working Group on Sarcopenia in Older People [1]. A small study comparing 30 sarcopenic vs 30 control individuals (77 ± 6 years, and 58% females) showed that sarcopenia may be associated with reduced diaphragmatic muscle thickness and respiratory functions. A recent publication shows that humans with sarcopenia, independently of their ethnicity, reproducibly exhibit a prominent transcriptional signature of mitochondrial bioenergetic dysfunction as evidenced by low PGC-1α/ERRα signaling and downregulation of mitochondrial proteostasis genes These changes result in fewer mitochondria, reduction of respiratory complex expression and activity, as well as low nicotinamide adenine dinucleotide (NAD+) levels due to its disturbed biosynthesis [41]. The aim of this review is to increase clinical awareness of sarcopenia, with a particular focus on current pathogenetic knowledge and therapeutic possibilities that may counteract wasting disorders in chronic heart failure

Sarcopenia in HF

Findings

Sarcopenia in Cardiac Cachexia