CT fatty muscle fraction as a new parameter for muscle quality assessment predicts outcome in venovenous extracorporeal membrane oxygenation

Abstract

Impaired skeletal muscle quality is a major risk factor for adverse outcomes in acute respiratory failure. However, conventional methods for skeletal muscle assessment are inapplicable in the critical care setting. This study aimed to determine the prognostic value of computed tomography (CT) fatty muscle fraction (FMF) as a biomarker of muscle quality in patients undergoing extracorporeal membrane oxygenation (ECMO). To calculate FMF, paraspinal skeletal muscle area was obtained from clinical CT and separated into areas of fatty and lean muscle based on densitometric thresholds. The cohort was binarized according to median FMF. Patients with high FMF displayed significantly increased 1-year mortality (72.7% versus 55.8%, P = 0.036) on Kaplan–Meier analysis. A multivariable logistic regression model was built to test the impact of FMF on outcome. FMF was identified as a significant predictor of 1-year mortality (hazard ratio per percent FMF, 1.017 [95% confidence interval, 1.002–1.033]; P = 0.031), independent of anthropometric characteristics, Charlson Comorbidity Index, Simplified Acute Physiology Score, Respiratory Extracorporeal Membrane Oxygenation Survival Prediction Score, and duration of ECMO support. To conclude, FMF predicted 1-year mortality independently of established clinical prognosticators in ECMO patients and may have the potential to become a new muscle quality imaging biomarker, which is available from clinical CT.

End-to-end automated body composition analyses with integrated quality control for opportunistic assessment of sarcopenia in CT

“…Thereby, FMF was recently proposed as an easy-accessible body composition metric which may be considered particularly promising as it additionally integrates information on skeletal muscle quality [1,5]. Previous studies have demonstrated its prognostic value both as an indicator of frailty in patients with planned endovascular aortic valve replacement as well as an powerful predictor of outcome in critically ill patients receiving extracorporeal membrane oxygenation therapy [1,6].…”

“…In the second part, the extracted 2D image is segmented into three compartment classes: visceral and subcutaneous adipose tissue (VAT, SAT) and skeletal muscle (SM). The fatty muscle fraction (FMF), a quantitative marker for fatty muscle degeneration, is determined in a subsequent post-processing step [1,6]. For both deeplearning-based slice extraction and segmentation, classical machine learning methods were employed for integration of quality control steps that capture the predictive uncertainty during deployment.…”

“…determined from abdominal imaging provide prognostic implications in oncologic or cardiovascular diseases [1][2][3][4][5][6][7][8].…”

Modalities of Exercise Training in Patients with Extracorporeal Membrane Oxygenation Support

“…In another study by Bear DE et al, the initial condition of the skeletal muscle index of patients with ARDS was related to the duration of VV ECMO, and most specifically, low skeletal muscle index resulted in longer VV ECMO duration, while preserved initial skeletal muscle index was associated with better survival [36]. Finally, fatty muscle fraction through CT imaging seems to be a predicting biomarker of 1-year mortality and a promising muscle quality imaging biomarker in ECMO patients [37].…”

Computed tomography derived cervical fat-free muscle fraction as an imaging-based outcome marker in patients with acute ischemic stroke: a pilot study

“…Skeletal muscle quality is an established target and determinant of functional recovery and thereby outcome in patients with acute severe illness [ 5 ]. Fatty infiltration of skeletal muscle, also called myosteatosis, is a progressive multifactorial skeletal muscle affection, which is commonly associated with aging and obesity and is known to increase the risk of adverse clinical outcomes and physical disability in many pathologies [ 5 – 11 ].…”