The assessment of muscle stiffness by SWE in patient with arterio-venous fistula for haemodialysis access

Abstract

Objectives: Arteriovenous fistula (AVF) failure is a significant cause of morbidity in hemodialysis patients. Shear Wave Elastography (SWE) is a non-invasive imaging technique that quantitatively assesses tissue stiffness. This study aimed to investigate the association between the stiffness of the biceps brachii muscle (measured by SWE) with the functional status of established brachiocephalic AVFs. Method: This study was conducted on 30 participants: 10 healthy controls and 20 patients with a brachiocephalic AVF. The patient was subdivided into a Study group with a patent, functioning fistula (n=13) and a Failed group with a non-functioning fistula (n=7). All participants underwent a standardized ultrasound examination to measure biceps muscle stiffness (SWE, in kPa), brachial artery diameter, peak systolic velocity (PSV), and volume flow rate. Result: No statistically significant difference in mean biceps muscle stiffness was observed among the control (25.87 ± 5.19 kPa), functioning AVF (24.90 ± 5.88 kPa), and failed AVF (23.26 ± 4.27 kPa) groups. An Analysis of Covariance (ANCOVA) confirmed this lack of difference remained after controlling for the confounding effects of age, BMI, hypertension, and diabetes (p = .494). Furthermore, muscle stiffness showed no significant correlation with key hemodynamic parameters of AVF function, including volume flow rate (r = -.067, p = .780). However, hemodynamic measures were significantly elevated in the functioning AVF group compared to the other groups (p < .001). Conclusion: SWE-measured biceps muscle stiffness does not seem to be a good indicator of the functional state of known brachiocephalic AVFs. Muscle characteristics are probably more influenced by the systemic effects of chronic kidney disease and patient comorbidities than by the fistula's local hemodynamic effects. SWE of the biceps muscle is not advised for the regular clinical monitoring of AVF function in light of these findings.