Psoas muscle size, possible sarcopenia and frailty, and long-term survival in elderly patients after isolated surgical aortic valve replacement for aortic stenosis

Abstract

Purpose: This study investigated the use of psoas muscle area index (PAI) as an indicator of mortality risk in relation to survival in elderly patients after isolated surgical aortic valve replacement (SAVR) for aortic valve stenosis (AS). Methods: Between January 2005 and March 2015, 140 patients with AS, aged ≥ 70 years, and with preoperative abdominal computed tomography scans, underwent elective, primary, isolated SAVR. PAI showed the ratio of the psoas muscle cross-sectional area at the fourth lumbar vertebral level to body surface area, and PAI less than the gender-specific lowest 20th percentile we called “low PAI” for the purposes of this study. Patients were classified as low PAI (n = 29) or normal PAI (n = 111). Results: The mean age in the low-PAI group was significantly older than in the normal-PAI group (81.0 vs. 77.3 years; p = 0.001). The mean follow-up was 4.25 years. The low-PAI group had a lower survival rate than the normal-PAI group at 1 year (89.7 ± 5.7% vs. 96.3 ± 1.8%), at 3 years (71.6 ± 9.3% vs. 91.5 ± 2.7%), and overall (53.0 ± 13.4% vs. 76.0 ± 5.6%; p = 0.039). The prognostic factors of mortality included low PAI (hazard ratio 2.95; 95% confidence interval 1.084–8.079; p = 0.034). Conclusions: PAI was associated with reduced overall survival after isolated SAVR in elderly people. PAI measurement may help to predict patient risks.