The Sarcopenia Index Correlates with Computed Tomography Quantified Muscle Measures in Patients with Advanced Heart Failure

Abstract

<h3>Purpose</h3> Patients with heart failure (HF) and sarcopenia and/or cachexia have a high mortality. No biomarkers are proven to diagnose or screen for sarcopenia in patients with HF. The purpose of this analysis is to assess the correlation between the sarcopenia index (SI) and CT quantified muscle measurements in advanced HF patients. <h3>Methods</h3> We prospectively collected serum creatinine, cystatin C and pre-operative chest CT scans in 60 patients as part of routine LVAD evaluation between 5/19 to 3/21. The sarcopenia index was calculated using the following equation: (serum creatinine value/cystatin C value) × 100. To quantify muscle mass and quality, unilateral pectoralis muscle mass indexed to body surface area (PMI) and attenuation (approximated by mean Hounsfield units; PHUm) were measured on pre-operative chest CTs. The correlation between the SI and muscle measures was evaluated with linear regression. <h3>Results</h3> Seventy three percent were men (44/60) and 67 % (40/60) were designated as destination therapy. There was a significant correlation between the SI and both pectoralis muscle measures (Figure). Each 10 unit increase in SI was associated with a 0.43 cm²/m² increase in PMI (95 % CI 0.11-0.76 increase, p=0.009) and a 3.47 HU increase in PHUm (95 % CI 2.08-4.87, p< 0.0001). <h3>Conclusion</h3> This is the first study to demonstrate a correlation between the SI and CT derived muscle measurements in an advanced HF population. A HF sarcopenia biomarker has multiple potential clinical applications, including facilitating nutritional/rehabilitation interventions before wasting is clinically evident, as well as triggering earlier referral for advanced HF therapies.