Trunk Muscle Cross-Sectional Area as a Predictive Factor for Length of Postoperative Hospitalization after Surgical Aortic Valve Replacement

Purpose: We investigated the utility of trunk muscle cross-sectional area to predict length of hospitalization after surgical aortic valve replacement (AVR) for aortic stenosis (AS). Methods: Adult AS patients who underwent isolated AVR at a single institution were studied. The cross-sectional area of the erector spinae muscles (ESM) at the first and second lumbar vertebrae and that of the psoas muscle (PM) at the third and fourth lumbar vertebrae were measured on preoperative computed tomography (CT). Each was indexed to body surface area. Risk factors for prolonged postoperative hospitalization (>3 weeks) were assessed using multivariate regression analyses. Results: Of 56 patients (mean age 76 ± 9 years; 25 men), 20 (35.7%) patients required prolonged hospitalization. A smaller indexed ESM cross-sectional area at the first lumbar vertebra (per 1 cm/m(2), odds ratio [OR] = 0.71, 95% confidence interval [CI] = 0.57–0.88, P <0.01) and lower preoperative serum albumin level (per 0.1 g/dL, OR = 0.83, 95% CI = 0.70–0.99, P <0.05) were shown as independent predictors. Indexed PM cross- sectional area was not statistically significant. Conclusion: The cross-sectional area of the trunk muscles can be used to identify patients at risk for prolonged hospitalization after AVR for adult AS.