CT-based ECV as a screening tool for transthyretin cardiac amyloidosis in severe aortic stenosis

Abstract Background Transthyretin cardiac amyloidosis (ATTR-CM) is increasingly recognized in patients with severe aortic stenosis (AS), particularly elderly individuals undergoing transcatheter aortic valve implantation (TAVI). It may affect up to 1 in 8 patients over 65 years with severe AS. The 2021 ESC position statement by Garcia-Pavia et al. recommends screening patients aged ≥65 years with severe AS and left ventricular hypertrophy, though uptake remains low—partly due to uncertainty in selecting appropriate candidates. Extracellular volume (ECV) quantification by cardiac CT has emerged as a reproducible, objective tool to support screening. Incorporated into standard pre-TAVI protocols via delayed acquisitions, it enables myocardial tissue characterization without workflow disruption. Scully et al. validated CT-derived ECV thresholds with high sensitivity and negative predictive value (NPV) for excluding cardiac uptake on scintigraphy: ECV