Does indexed aortic valve calcium volume from CTA provide diagnostic discrimination and risk stratification in patients with aortic stenosis?
Indexed aortic valve calcium volume from CTA provides accurate discrimination of aortic stenosis severity and independently predicts aortic valve replacement or all-cause mortality.
BACKGROUND: Calcium scoring from noncontrast computed tomography (CT) is used clinically to adjudicate aortic stenosis severity in patients with discordant echocardiography. OBJECTIVES: The aim of this study was to investigate whether quantification of aortic valve calcium volume from computed tomography angiography (CTA) can provide robust diagnostic discrimination of disease severity and inform risk stratification of patients with aortic stenosis. METHODS: Patients with mild to severe aortic stenosis who underwent concurrent CTA and echocardiography were included in a retrospective international multicenter observational cohort study. Accuracy of aortic valve calcium volume to diagnose severe aortic stenosis in patients with concordant disease on echocardiography was assessed. Association of aortic valve calcium volume with the incidence of aortic valve replacement or all-cause death was investigated. RESULTS: ) provided excellent diagnostic discrimination for severe aortic stenosis (C-statistic: 0.900 for men; 0.926 for women). Similar diagnostic discrimination was observed in the validation cohort (n = 459; C-statistic: 0.933 for men; 0.944 for women). Clinical outcomes were available in 711 patients (25% with discordant echocardiography), with 249 reaching the primary endpoint after 26 months (Q1-Q3: 12-53 months). Indexed calcium volume thresholds were independently associated with aortic valve replacement or all-cause mortality in both the cohort as a whole (HR: 2.01 95% CI: 1.30-3.10; P < 0.01) and those with discordant echocardiography (HR: 1.58 95% CI: 1.01-2.44). CONCLUSIONS: In patients with aortic stenosis, indexed aortic valve calcium volume from CTA provides accurate discrimination of disease severity and additive prognostic information. This technique can be easily applied to patients undergoing CTA for transcatheter aortic valve replacement or coronary artery evaluation without the need for a separate noncontrast CT scan.
Geers et al. (2025) studied this question.