Abstract 10564: Inverse Association Between Serum Albumin Levels and Myocardial Extracellular Volume in Patients with Severe Aortic Stenosis

Abstract

Introduction: Severe aortic stenosis (AS) is often characterized by myocardial interstitial fibrosis (MIF). MIF, classically measured by magnetic resonance imaging, was shown to be accurately measured by computed tomography (CT)-derived extra cellular volume fraction (ECVF). Serum albumin level (SA, g/dL) has been shown to correlate with ECVF among patients with heart failure preserved ejection fraction. Aim: To evaluate the association between SA and ECVF among patients with severe symptomatic AS. Methods: Patients with symptomatic severe AS who were evaluated as candidates for intervention between 2016 and 2018, were enrolled prospectively. All patients underwent pre- and post-contrast CT for estimating myocardial ECVF. Valid ambulatory SA within 6 weeks of the cardiac CT were obtained and classified as (tertials): <3.8, (3.8-4.19), ≥4.2 g/dL. Patients with acute systemic illness at the time of the albumin test were exclude. Results: The study included 68 patients, mean age 80.94±6.5, 53% females. Patients with lower SA were more likely to have chronic renal failure, prior percutaneous coronary interventions (PCI) and a reduced functional class. The mean ECVF (%) in the study cohort was 40.96±11.6%, significantly higher among the patients in the lower SA level groups (50±11.6% vs. 38.2±7.3% vs. 32.8±8.6% in the <3.8 g/dL, 3.8-4.19 g/dL, ≥4.2 g/dL groups respectively, p for trend<0.001). A statistically significant inverse correlation (figure 1) was found between SA levels and ECVF (r=-0.7, p<0.001). Multivariable analysis showed significant independent association between low SA and ECVF. Conclusions: SA level is inversely associated with CT-derived ECVF in patients with severe AS. Additional studies are warranted to elucidate the pathophysiological mechanisms explaining the observed association and potential clinical implications